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authorMichal Krol <[email protected]>2004-03-04 13:07:52 +0000
committerMichal Krol <[email protected]>2004-03-04 13:07:52 +0000
commita904b493a9f86a9cfcfff032255352b7050ef271 (patch)
treeca70d6c024e2285d90edaa1fd3c19f423862a248 /src/mesa/shader/grammar.c
parent2462f6bfa0ca71390439104f751310da89a69d1a (diff)
Added missing Copyrights.
Diffstat (limited to 'src/mesa/shader/grammar.c')
-rw-r--r--src/mesa/shader/grammar.c5559
1 files changed, 2799 insertions, 2760 deletions
diff --git a/src/mesa/shader/grammar.c b/src/mesa/shader/grammar.c
index 96449784571..0ed347bad51 100644
--- a/src/mesa/shader/grammar.c
+++ b/src/mesa/shader/grammar.c
@@ -1,2760 +1,2799 @@
-#ifndef GRAMMAR_PORT_BUILD
-#error Do not build this file directly, build your grammar_XXX.c instead, which includes this file
-#endif
-
-/*
- Last Modified: 2004-II-8
-*/
-
-/*
- INTRODUCTION
- ------------
-
- The task is to check the syntax of an input string. Input string is a stream of ASCII
- characters terminated with a null-character ('\0'). Checking it using C language is
- difficult and hard to implement without bugs. It is hard to maintain and make changes when
- the syntax changes.
-
- This is because of a high redundancy of the C code. Large blocks of code are duplicated with
- only small changes. Even use of macros does not solve the problem because macros cannot
- erase the complexity of the problem.
-
- The resolution is to create a new language that will be highly oriented to our task. Once
- we describe a particular syntax, we are done. We can then focus on the code that implements
- the language. The size and complexity of it is relatively small than the code that directly
- checks the syntax.
-
- First, we must implement our new language. Here, the language is implemented in C, but it
- could also be implemented in any other language. The code is listed below. We must take
- a good care that it is bug free. This is simple because the code is simple and clean.
-
- Next, we must describe the syntax of our new language in itself. Once created and checked
- manually that it is correct, we can use it to check another scripts.
-
- Note that our new language loading code does not have to check the syntax. It is because we
- assume that the script describing itself is correct, and other scripts can be syntactically
- checked by the former script. The loading code must only do semantic checking which leads us to
- simple resolving references.
-
- THE LANGUAGE
- ------------
-
- Here I will describe the syntax of the new language (further called "Synek"). It is mainly a
- sequence of declarations terminated by a semicolon. The declaration consists of a symbol,
- which is an identifier, and its definition. A definition is in turn a sequence of specifiers
- connected with ".and" or ".or" operator. These operators cannot be mixed together in a one
- definition. Specifier can be a symbol, string, character, character range or a special
- keyword ".true" or ".false".
-
- On the very beginning of the script there is a declaration of a root symbol and is in the form:
- .syntax <root_symbol>;
- The <root_symbol> must be on of the symbols in declaration sequence. The syntax is correct if
- the root symbol evaluates to true. A symbol evaluates to true if the definition associated with
- the symbol evaluates to true. Definition evaluation depends on the operator used to connect
- specifiers in the definition. If ".and" operator is used, definition evaluates to true if and
- only if all the specifiers evaluate to true. If ".or" operator is used, definition evalutes to
- true if any of the specifiers evaluates to true. If definition contains only one specifier,
- it is evaluated as if it was connected with ".true" keyword by ".and" operator.
-
- If specifier is a ".true" keyword, it always evaluates to true.
-
- If specifier is a ".false" keyword, it always evaluates to false. Specifier evaluates to false
- when it does not evaluate to true.
-
- Character range specifier is in the form:
- '<first_character>' - '<second_character>'
- If specifier is a character range, it evaluates to true if character in the stream is greater
- or equal to <first_character> and less or equal to <second_character>. In that situation
- the stream pointer is advanced to point to next character in the stream. All C-style escape
- sequences are supported although trigraph sequences are not. The comparisions are performed
- on 8-bit unsigned integers.
-
- Character specifier is in the form:
- '<single_character>'
- It evaluates to true if the following character range specifier evaluates to true:
- '<single_character>' - '<single_character>'
-
- String specifier is in the form:
- "<string>"
- Let N be the number of characters in <string>. Let <string>[i] designate i-th character in
- <string>. Then the string specifier evaluates to true if and only if for i in the range [0, N)
- the following character specifier evaluates to true:
- '<string>[i]'
- If <string>[i] is a quotation mark, '<string>[i]' is replaced with '\<string>[i]'.
-
- Symbol specifier can be optionally preceded by a ".loop" keyword in the form:
- .loop <symbol> (1)
- where <symbol> is defined as follows:
- <symbol> <definition>; (2)
- Construction (1) is replaced by the following code:
- <symbol$1>
- and declaration (2) is replaced by the following:
- <symbol$1> <symbol$2> .or .true;
- <symbol$2> <symbol> .and <symbol$1>;
- <symbol> <definition>;
-
- ESCAPE SEQUENCES
- ----------------
-
- Synek supports all escape sequences in character specifiers. The mapping table is listed below.
- All occurences of the characters in the first column are replaced with the corresponding
- character in the second column.
-
- Escape sequence Represents
- ------------------------------------------------------------------------------------------------
- \a Bell (alert)
- \b Backspace
- \f Formfeed
- \n New line
- \r Carriage return
- \t Horizontal tab
- \v Vertical tab
- \' Single quotation mark
- \" Double quotation mark
- \\ Backslash
- \? Literal question mark
- \ooo ASCII character in octal notation
- \xhhh ASCII character in hexadecimal notation
- ------------------------------------------------------------------------------------------------
-
- RAISING ERRORS
- --------------
-
- Any specifier can be followed by a special construction that is executed when the specifier
- evaluates to false. The construction is in the form:
- .error <ERROR_TEXT>
- <ERROR_TEXT> is an identifier declared earlier by error text declaration. The declaration is
- in the form:
- .errtext <ERROR_TEXT> "<error_desc>"
- When specifier evaluates to false and this construction is present, parsing is stopped
- immediately and <error_desc> is returned as a result of parsing. The error position is also
- returned and it is meant as an offset from the beggining of the stream to the character that
- was valid so far. Example:
-
- (**** syntax script ****)
-
- .syntax program;
- .errtext MISSING_SEMICOLON "missing ';'"
- program declaration .and .loop space .and ';' .error MISSING_SEMICOLON .and
- .loop space .and '\0';
- declaration "declare" .and .loop space .and identifier;
- space ' ';
-
- (**** sample code ****)
-
- declare foo ,
-
- In the example above checking the sample code will result in error message "missing ';'" and
- error position 12. The sample code is not correct. Note the presence of '\0' specifier to
- assure that there is no code after semicolon - only spaces.
- <error_desc> can optionally contain identifier surrounded by dollar signs $. In such a case,
- the identifier and dollar signs are replaced by a string retrieved by invoking symbol with
- the identifier name. The starting position is the error position. The lenght of the resulting
- string is the position after invoking the symbol.
-
- PRODUCTION
- ----------
-
- Synek not only checks the syntax but it can also produce (emit) bytes associated with specifiers
- that evaluate to true. That is, every specifier and optional error construction can be followed
- by a number of emit constructions that are in the form:
- .emit <parameter>
- <paramater> can be a HEX number, identifier, a star * or a dollar $. HEX number is preceded by
- 0x or 0X. If <parameter> is an identifier, it must be earlier declared by emit code declaration
- in the form:
- .emtcode <identifier> <hex_number>
-
- When given specifier evaluates to true, all emits associated with the specifier are output
- in order they were declared. A star means that last-read character should be output instead
- of constant value. Example:
-
- (**** syntax script ****)
-
- .syntax foobar;
- .emtcode WORD_FOO 0x01
- .emtcode WORD_BAR 0x02
- foobar FOO .emit WORD_FOO .or BAR .emit WORD_BAR .or .true .emit 0x00;
- FOO "foo" .and SPACE;
- BAR "bar" .and SPACE;
- SPACE ' ' .or '\0';
-
- (**** sample text 1 ****)
-
- foo
-
- (**** sample text 2 ****)
-
- foobar
-
- For both samples the result will be one-element array. For first sample text it will be
- value 1, for second - 0. Note that every text will be accepted because of presence of
- .true as an alternative.
-
- Another example:
-
- (**** syntax script ****)
-
- .syntax declaration;
- .emtcode VARIABLE 0x01
- declaration "declare" .and .loop space .and
- identifier .emit VARIABLE .and (1)
- .true .emit 0x00 .and (2)
- .loop space .and ';';
- space ' ' .or '\t';
- identifier .loop id_char .emit *; (3)
- id_char 'a'-'z' .or 'A'-'Z' .or '_';
-
- (**** sample code ****)
-
- declare fubar;
-
- In specifier (1) symbol <identifier> is followed by .emit VARIABLE. If it evaluates to
- true, VARIABLE constant and then production of the symbol is output. Specifier (2) is used
- to terminate the string with null to signal when the string ends. Specifier (3) outputs
- all characters that make declared identifier. The result of sample code will be the
- following array:
- { 1, 'f', 'u', 'b', 'a', 'r', 0 }
-
- If .emit is followed by dollar $, it means that current position should be output. Current
- position is a 32-bit unsigned integer distance from the very beginning of the parsed string to
- first character consumed by the specifier associated with the .emit instruction. Current
- position is stored in the output buffer in Little-Endian convention (the lowest byte comes
- first).
-*/
-
-static void mem_free (void **);
-
-/*
- internal error messages
-*/
-static const byte *OUT_OF_MEMORY = (byte *) "internal error 1001: out of physical memory";
-static const byte *UNRESOLVED_REFERENCE = (byte *) "internal error 1002: unresolved reference '$'";
-static const byte *INVALID_GRAMMAR_ID = (byte *) "internal error 1003: invalid grammar object";
-static const byte *INVALID_REGISTER_NAME = (byte *) "internal error 1004: invalid register name: '$'";
-
-static const byte *error_message = NULL;
-static byte *error_param = NULL; /* this is inserted into error_message in place of $ */
-static int error_position = -1;
-
-static byte *unknown = (byte *) "???";
-
-static void clear_last_error ()
-{
- /* reset error message */
- error_message = NULL;
-
- /* free error parameter - if error_param is a "???" don't free it - it's static */
- if (error_param != unknown)
- mem_free ((void **) &error_param);
- else
- error_param = NULL;
-
- /* reset error position */
- error_position = -1;
-}
-
-static void set_last_error (const byte *msg, byte *param, int pos)
-{
- /* error message can only be set only once */
- if (error_message != NULL)
- {
- mem_free (&param);
- return;
- }
-
- error_message = msg;
-
- if (param != NULL)
- error_param = param;
- else
- error_param = unknown;
-
- error_position = pos;
-}
-
-/*
- memory management routines
-*/
-static void *mem_alloc (size_t size)
-{
- void *ptr = grammar_alloc_malloc (size);
- if (ptr == NULL)
- set_last_error (OUT_OF_MEMORY, NULL, -1);
- return ptr;
-}
-
-static void *mem_copy (void *dst, const void *src, size_t size)
-{
- return grammar_memory_copy (dst, src, size);
-}
-
-static void mem_free (void **ptr)
-{
- grammar_alloc_free (*ptr);
- *ptr = NULL;
-}
-
-static void *mem_realloc (void *ptr, size_t old_size, size_t new_size)
-{
- void *ptr2 = grammar_alloc_realloc (ptr, old_size, new_size);
- if (ptr2 == NULL)
- set_last_error (OUT_OF_MEMORY, NULL, -1);
- return ptr2;
-}
-
-static byte *str_copy_n (byte *dst, const byte *src, size_t max_len)
-{
- return grammar_string_copy_n (dst, src, max_len);
-}
-
-static byte *str_duplicate (const byte *str)
-{
- byte *new_str = grammar_string_duplicate (str);
- if (new_str == NULL)
- set_last_error (OUT_OF_MEMORY, NULL, -1);
- return new_str;
-}
-
-static int str_equal (const byte *str1, const byte *str2)
-{
- return grammar_string_compare (str1, str2) == 0;
-}
-
-static int str_equal_n (const byte *str1, const byte *str2, unsigned int n)
-{
- return grammar_string_compare_n (str1, str2, n) == 0;
-}
-
-static unsigned int str_length (const byte *str)
-{
- return grammar_string_length (str);
-}
-
-/*
- string to byte map typedef
-*/
-typedef struct map_byte_
-{
- byte *key;
- byte data;
- struct map_byte_ *next;
-} map_byte;
-
-static void map_byte_create (map_byte **ma)
-{
- *ma = mem_alloc (sizeof (map_byte));
- if (*ma)
- {
- (**ma).key = NULL;
- (**ma).data = '\0';
- (**ma).next = NULL;
- }
-}
-
-/* XXX unfold the recursion */
-static void map_byte_destroy (map_byte **ma)
-{
- if (*ma)
- {
- map_byte_destroy (&(**ma).next);
- mem_free ((void **) &(**ma).key);
- mem_free ((void **) ma);
- }
-}
-
-static void map_byte_append (map_byte **ma, map_byte **nm)
-{
- while (*ma)
- ma = &(**ma).next;
- *ma = *nm;
-}
-
-/*
- searches the map for the specified key,
- returns pointer to the element with the specified key if it exists
- returns NULL otherwise
-*/
-map_byte *map_byte_locate (map_byte **ma, const byte *key)
-{
- while (*ma)
- {
- if (str_equal ((**ma).key, key))
- return *ma;
-
- ma = &(**ma).next;
- }
-
- set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
- return NULL;
-}
-
-/*
- searches the map for specified key,
- if the key is matched, *data is filled with data associated with the key,
- returns 0 if the key is matched,
- returns 1 otherwise
-*/
-static int map_byte_find (map_byte **ma, const byte *key, byte *data)
-{
- map_byte *found = map_byte_locate (ma, key);
- if (found != NULL)
- {
- *data = found->data;
-
- return 0;
- }
-
- return 1;
-}
-
-/*
- regbyte context typedef
-
- Each regbyte consists of its name and a default value. These are static and created at
- grammar script compile-time, for example the following line:
- .regbyte vertex_blend 0x00
- adds a new regbyte named "vertex_blend" to the static list and initializes it to 0.
- When the script is executed, this regbyte can be accessed by name for read and write. When a
- particular regbyte is written, a new regbyte_ctx entry is added to the top of the regbyte_ctx
- stack. The new entry contains information abot which regbyte it references and its new value.
- When a given regbyte is accessed for read, the stack is searched top-down to find an
- entry that references the regbyte. The first matching entry is used to return the current
- value it holds. If no entry is found, the default value is returned.
-*/
-typedef struct regbyte_ctx_
-{
- map_byte *m_regbyte;
- byte m_current_value;
- struct regbyte_ctx_ *m_prev;
-} regbyte_ctx;
-
-static void regbyte_ctx_create (regbyte_ctx **re)
-{
- *re = mem_alloc (sizeof (regbyte_ctx));
- if (*re)
- {
- (**re).m_regbyte = NULL;
- (**re).m_prev = NULL;
- }
-}
-
-static void regbyte_ctx_destroy (regbyte_ctx **re)
-{
- if (*re)
- {
- mem_free ((void **) re);
- }
-}
-
-static byte regbyte_ctx_extract (regbyte_ctx **re, map_byte *reg)
-{
- /* first lookup in the register stack */
- while (*re != NULL)
- {
- if ((**re).m_regbyte == reg)
- return (**re).m_current_value;
-
- re = &(**re).m_prev;
- }
-
- /* if not found - return the default value */
- return reg->data;
-}
-
-/*
- emit type typedef
-*/
-typedef enum emit_type_
-{
- et_byte, /* explicit number */
- et_stream, /* eaten character */
- et_position /* current position */
-} emit_type;
-
-/*
- emit destination typedef
-*/
-typedef enum emit_dest_
-{
- ed_output, /* write to the output buffer */
- ed_regbyte /* write a particular regbyte */
-} emit_dest;
-
-/*
- emit typedef
-*/
-typedef struct emit_
-{
- emit_dest m_emit_dest;
- emit_type m_emit_type; /* ed_output */
- byte m_byte; /* et_byte */
- map_byte *m_regbyte; /* ed_regbyte */
- byte *m_regname; /* ed_regbyte - temporary */
- struct emit_ *m_next;
-} emit;
-
-static void emit_create (emit **em)
-{
- *em = mem_alloc (sizeof (emit));
- if (*em)
- {
- (**em).m_emit_dest = ed_output;
- (**em).m_emit_type = et_byte;
- (**em).m_byte = '\0';
- (**em).m_regbyte = NULL;
- (**em).m_regname = NULL;
- (**em).m_next = NULL;
- }
-}
-
-static void emit_destroy (emit **em)
-{
- if (*em)
- {
- emit_destroy (&(**em).m_next);
- mem_free ((void **) &(**em).m_regname);
- mem_free ((void **) em);
- }
-}
-
-/*
- error typedef
-*/
-typedef struct error_
-{
- byte *m_text;
- byte *m_token_name;
- struct rule_ *m_token;
-} error;
-
-static void error_create (error **er)
-{
- *er = mem_alloc (sizeof (error));
- if (*er)
- {
- (**er).m_text = NULL;
- (**er).m_token_name = NULL;
- (**er).m_token = NULL;
- }
-}
-
-static void error_destroy (error **er)
-{
- if (*er)
- {
- mem_free ((void **) &(**er).m_text);
- mem_free ((void **) &(**er).m_token_name);
- mem_free ((void **) er);
- }
-}
-
-struct dict_;
-static byte *error_get_token (error *, struct dict_ *, const byte *, unsigned int);
-
-/*
- condition operand type typedef
-*/
-typedef enum cond_oper_type_
-{
- cot_byte, /* constant 8-bit unsigned integer */
- cot_regbyte /* pointer to byte register containing the current value */
-} cond_oper_type;
-
-/*
- condition operand typedef
-*/
-typedef struct cond_oper_
-{
- cond_oper_type m_type;
- byte m_byte; /* cot_byte */
- map_byte *m_regbyte; /* cot_regbyte */
- byte *m_regname; /* cot_regbyte - temporary */
-} cond_oper;
-
-/*
- condition type typedef
-*/
-typedef enum cond_type_
-{
- ct_equal,
- ct_not_equal
-} cond_type;
-
-/*
- condition typedef
-*/
-typedef struct cond_
-{
- cond_type m_type;
- cond_oper m_operands[2];
-} cond;
-
-static void cond_create (cond **co)
-{
- *co = mem_alloc (sizeof (cond));
- if (*co)
- {
- (**co).m_operands[0].m_regname = NULL;
- (**co).m_operands[1].m_regname = NULL;
- }
-}
-
-static void cond_destroy (cond **co)
-{
- if (*co)
- {
- mem_free ((void **) &(**co).m_operands[0].m_regname);
- mem_free ((void **) &(**co).m_operands[1].m_regname);
- mem_free ((void **) co);
- }
-}
-
-/*
- specifier type typedef
-*/
-typedef enum spec_type_
-{
- st_false,
- st_true,
- st_byte,
- st_byte_range,
- st_string,
- st_identifier,
- st_identifier_loop,
- st_debug
-} spec_type;
-
-/*
- specifier typedef
-*/
-typedef struct spec_
-{
- spec_type m_spec_type;
- byte m_byte[2]; /* st_byte, st_byte_range */
- byte *m_string; /* st_string */
- struct rule_ *m_rule; /* st_identifier, st_identifier_loop */
- emit *m_emits;
- error *m_errtext;
- cond *m_cond;
- struct spec_ *m_next;
-} spec;
-
-static void spec_create (spec **sp)
-{
- *sp = mem_alloc (sizeof (spec));
- if (*sp)
- {
- (**sp).m_spec_type = st_false;
- (**sp).m_byte[0] = '\0';
- (**sp).m_byte[1] = '\0';
- (**sp).m_string = NULL;
- (**sp).m_rule = NULL;
- (**sp).m_emits = NULL;
- (**sp).m_errtext = NULL;
- (**sp).m_cond = NULL;
- (**sp).m_next = NULL;
- }
-}
-
-static void spec_destroy (spec **sp)
-{
- if (*sp)
- {
- spec_destroy (&(**sp).m_next);
- emit_destroy (&(**sp).m_emits);
- error_destroy (&(**sp).m_errtext);
- mem_free ((void **) &(**sp).m_string);
- cond_destroy (&(**sp).m_cond);
- mem_free ((void **) sp);
- }
-}
-
-static void spec_append (spec **sp, spec **ns)
-{
- while (*sp)
- sp = &(**sp).m_next;
- *sp = *ns;
-}
-
-/*
- operator typedef
-*/
-typedef enum oper_
-{
- op_none,
- op_and,
- op_or
-} oper;
-
-/*
- rule typedef
-*/
-typedef struct rule_
-{
- oper m_oper;
- spec *m_specs;
- struct rule_ *m_next;
-/* int m_referenced; */ /* for debugging purposes */
-} rule;
-
-static void rule_create (rule **ru)
-{
- *ru = mem_alloc (sizeof (rule));
- if (*ru)
- {
- (**ru).m_oper = op_none;
- (**ru).m_specs = NULL;
- (**ru).m_next = NULL;
-/* (**ru).m_referenced = 0; */
- }
-}
-
-static void rule_destroy (rule **ru)
-{
- if (*ru)
- {
- rule_destroy (&(**ru).m_next);
- spec_destroy (&(**ru).m_specs);
- mem_free ((void **) ru);
- }
-}
-
-static void rule_append (rule **ru, rule **nr)
-{
- while (*ru)
- ru = &(**ru).m_next;
- *ru = *nr;
-}
-
-/*
- returns unique grammar id
-*/
-static grammar next_valid_grammar_id ()
-{
- static grammar id = 0;
-
- return ++id;
-}
-
-/*
- dictionary typedef
-*/
-typedef struct dict_
-{
- rule *m_rulez;
- rule *m_syntax;
- rule *m_string;
- map_byte *m_regbytes;
- grammar m_id;
- struct dict_ *m_next;
-} dict;
-
-static void dict_create (dict **di)
-{
- *di = mem_alloc (sizeof (dict));
- if (*di)
- {
- (**di).m_rulez = NULL;
- (**di).m_syntax = NULL;
- (**di).m_string = NULL;
- (**di).m_regbytes = NULL;
- (**di).m_id = next_valid_grammar_id ();
- (**di).m_next = NULL;
- }
-}
-
-static void dict_destroy (dict **di)
-{
- if (*di)
- {
- rule_destroy (&(**di).m_rulez);
- map_byte_destroy (&(**di).m_regbytes);
- mem_free ((void **) di);
- }
-}
-
-static void dict_append (dict **di, dict **nd)
-{
- while (*di)
- di = &(**di).m_next;
- *di = *nd;
-}
-
-static void dict_find (dict **di, grammar key, dict **data)
-{
- while (*di)
- {
- if ((**di).m_id == key)
- {
- *data = *di;
- return;
- }
-
- di = &(**di).m_next;
- }
-
- *data = NULL;
-}
-
-static dict *g_dicts = NULL;
-
-/*
- byte array typedef
-
- XXX this class is going to be replaced by a faster one, soon
-*/
-typedef struct barray_
-{
- byte *data;
- unsigned int len;
-} barray;
-
-static void barray_create (barray **ba)
-{
- *ba = mem_alloc (sizeof (barray));
- if (*ba)
- {
- (**ba).data = NULL;
- (**ba).len = 0;
- }
-}
-
-static void barray_destroy (barray **ba)
-{
- if (*ba)
- {
- mem_free ((void **) &(**ba).data);
- mem_free ((void **) ba);
- }
-}
-
-/*
- reallocates byte array to requested size,
- returns 0 on success,
- returns 1 otherwise
-*/
-static int barray_resize (barray **ba, unsigned int nlen)
-{
- byte *new_pointer;
-
- if (nlen == 0)
- {
- mem_free ((void **) &(**ba).data);
- (**ba).data = NULL;
- (**ba).len = 0;
-
- return 0;
- }
- else
- {
- new_pointer = mem_realloc ((**ba).data, (**ba).len * sizeof (byte), nlen * sizeof (byte));
- if (new_pointer)
- {
- (**ba).data = new_pointer;
- (**ba).len = nlen;
-
- return 0;
- }
- }
-
- return 1;
-}
-
-/*
- adds byte array pointed by *nb to the end of array pointed by *ba,
- returns 0 on success,
- returns 1 otherwise
-*/
-static int barray_append (barray **ba, barray **nb)
-{
- const unsigned int len = (**ba).len;
-
- if (barray_resize (ba, (**ba).len + (**nb).len))
- return 1;
-
- mem_copy ((**ba).data + len, (**nb).data, (**nb).len);
-
- return 0;
-}
-
-/*
- adds emit chain pointed by em to the end of array pointed by *ba,
- returns 0 on success,
- returns 1 otherwise
-*/
-static int barray_push (barray **ba, emit *em, byte c, unsigned int pos, regbyte_ctx **rbc)
-{
- emit *temp = em;
- unsigned int count = 0;
-
- while (temp)
- {
- if (temp->m_emit_dest == ed_output)
- if (temp->m_emit_type == et_position)
- count += 4; /* position is a 32-bit unsigned integer */
- else
- count++;
-
- temp = temp->m_next;
- }
-
- if (barray_resize (ba, (**ba).len + count))
- return 1;
-
- while (em)
- {
- if (em->m_emit_dest == ed_output)
- {
- if (em->m_emit_type == et_byte)
- (**ba).data[(**ba).len - count--] = em->m_byte;
- else if (em->m_emit_type == et_stream)
- (**ba).data[(**ba).len - count--] = c;
- else // em->type == et_position
- (**ba).data[(**ba).len - count--] = (byte) pos,
- (**ba).data[(**ba).len - count--] = (byte) (pos >> 8),
- (**ba).data[(**ba).len - count--] = (byte) (pos >> 16),
- (**ba).data[(**ba).len - count--] = (byte) (pos >> 24);
- }
- else
- {
- regbyte_ctx *new_rbc;
- regbyte_ctx_create (&new_rbc);
- if (new_rbc == NULL)
- return 1;
-
- new_rbc->m_prev = *rbc;
- new_rbc->m_regbyte = em->m_regbyte;
- *rbc = new_rbc;
-
- if (em->m_emit_type == et_byte)
- new_rbc->m_current_value = em->m_byte;
- else if (em->m_emit_type == et_stream)
- new_rbc->m_current_value = c;
- }
-
- em = em->m_next;
- }
-
- return 0;
-}
-
-/*
- string to string map typedef
-*/
-typedef struct map_str_
-{
- byte *key;
- byte *data;
- struct map_str_ *next;
-} map_str;
-
-static void map_str_create (map_str **ma)
-{
- *ma = mem_alloc (sizeof (map_str));
- if (*ma)
- {
- (**ma).key = NULL;
- (**ma).data = NULL;
- (**ma).next = NULL;
- }
-}
-
-static void map_str_destroy (map_str **ma)
-{
- if (*ma)
- {
- map_str_destroy (&(**ma).next);
- mem_free ((void **) &(**ma).key);
- mem_free ((void **) &(**ma).data);
- mem_free ((void **) ma);
- }
-}
-
-static void map_str_append (map_str **ma, map_str **nm)
-{
- while (*ma)
- ma = &(**ma).next;
- *ma = *nm;
-}
-
-/*
- searches the map for specified key,
- if the key is matched, *data is filled with data associated with the key,
- returns 0 if the key is matched,
- returns 1 otherwise
-*/
-static int map_str_find (map_str **ma, const byte *key, byte **data)
-{
- while (*ma)
- {
- if (str_equal ((**ma).key, key))
- {
- *data = str_duplicate ((**ma).data);
- if (*data == NULL)
- return 1;
-
- return 0;
- }
-
- ma = &(**ma).next;
- }
-
- set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
- return 1;
-}
-
-/*
- string to rule map typedef
-*/
-typedef struct map_rule_
-{
- byte *key;
- rule *data;
- struct map_rule_ *next;
-} map_rule;
-
-static void map_rule_create (map_rule **ma)
-{
- *ma = mem_alloc (sizeof (map_rule));
- if (*ma)
- {
- (**ma).key = NULL;
- (**ma).data = NULL;
- (**ma).next = NULL;
- }
-}
-
-static void map_rule_destroy (map_rule **ma)
-{
- if (*ma)
- {
- map_rule_destroy (&(**ma).next);
- mem_free ((void **) &(**ma).key);
- mem_free ((void **) ma);
- }
-}
-
-static void map_rule_append (map_rule **ma, map_rule **nm)
-{
- while (*ma)
- ma = &(**ma).next;
- *ma = *nm;
-}
-
-/*
- searches the map for specified key,
- if the key is matched, *data is filled with data associated with the key,
- returns 0 if the is matched,
- returns 1 otherwise
-*/
-static int map_rule_find (map_rule **ma, const byte *key, rule **data)
-{
- while (*ma)
- {
- if (str_equal ((**ma).key, key))
- {
- *data = (**ma).data;
-
- return 0;
- }
-
- ma = &(**ma).next;
- }
-
- set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
- return 1;
-}
-
-/*
- returns 1 if given character is a white space,
- returns 0 otherwise
-*/
-static int is_space (byte c)
-{
- return c == ' ' || c == '\t' || c == '\n' || c == '\r';
-}
-
-/*
- advances text pointer by 1 if character pointed by *text is a space,
- returns 1 if a space has been eaten,
- returns 0 otherwise
-*/
-static int eat_space (const byte **text)
-{
- if (is_space (**text))
- {
- (*text)++;
-
- return 1;
- }
-
- return 0;
-}
-
-/*
- returns 1 if text points to C-style comment start string "/*",
- returns 0 otherwise
-*/
-static int is_comment_start (const byte *text)
-{
- return text[0] == '/' && text[1] == '*';
-}
-
-/*
- advances text pointer to first character after C-style comment block - if any,
- returns 1 if C-style comment block has been encountered and eaten,
- returns 0 otherwise
-*/
-static int eat_comment (const byte **text)
-{
- if (is_comment_start (*text))
- {
- /* *text points to comment block - skip two characters to enter comment body */
- *text += 2;
- /* skip any character except consecutive '*' and '/' */
- while (!((*text)[0] == '*' && (*text)[1] == '/'))
- (*text)++;
- /* skip those two terminating characters */
- *text += 2;
-
- return 1;
- }
-
- return 0;
-}
-
-/*
- advances text pointer to first character that is neither space nor C-style comment block
-*/
-static void eat_spaces (const byte **text)
-{
- while (eat_space (text) || eat_comment (text))
- ;
-}
-
-/*
- resizes string pointed by *ptr to successfully add character c to the end of the string,
- returns 0 on success,
- returns 1 otherwise
-*/
-static int string_grow (byte **ptr, unsigned int *len, byte c)
-{
- /* reallocate the string in 16-byte increments */
- if ((*len & 0x0F) == 0x0F || *ptr == NULL)
- {
- byte *tmp = mem_realloc (*ptr, ((*len + 1) & ~0x0F) * sizeof (byte),
- ((*len + 1 + 0x10) & ~0x0F) * sizeof (byte));
- if (tmp == NULL)
- return 1;
-
- *ptr = tmp;
- }
-
- if (c)
- {
- /* append given character */
- (*ptr)[*len] = c;
- (*len)++;
- }
- (*ptr)[*len] = '\0';
-
- return 0;
-}
-
-/*
- returns 1 if given character is a valid identifier character a-z, A-Z, 0-9 or _
- returns 0 otherwise
-*/
-static int is_identifier (byte c)
-{
- return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_';
-}
-
-/*
- copies characters from *text to *id until non-identifier character is encountered,
- assumes that *id points to NULL object - caller is responsible for later freeing the string,
- text pointer is advanced to point past the copied identifier,
- returns 0 if identifier was successfully copied,
- returns 1 otherwise
-*/
-static int get_identifier (const byte **text, byte **id)
-{
- const byte *t = *text;
- byte *p = NULL;
- unsigned int len = 0;
-
- if (string_grow (&p, &len, '\0'))
- return 1;
-
- /* loop while next character in buffer is valid for identifiers */
- while (is_identifier (*t))
- {
- if (string_grow (&p, &len, *t++))
- {
- mem_free ((void **) &p);
- return 1;
- }
- }
-
- *text = t;
- *id = p;
-
- return 0;
-}
-
-/*
- returns 1 if given character is HEX digit 0-9, A-F or a-f,
- returns 0 otherwise
-*/
-static int is_hex (byte c)
-{
- return (c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f');
-}
-
-/*
- returns value of passed character as if it was HEX digit
-*/
-static unsigned int hex2dec (byte c)
-{
- if (c >= '0' && c <= '9')
- return c - '0';
- if (c >= 'A' && c <= 'F')
- return c - 'A' + 10;
- return c - 'a' + 10;
-}
-
-/*
- converts sequence of HEX digits pointed by *text until non-HEX digit is encountered,
- advances text pointer past the converted sequence,
- returns the converted value
-*/
-static unsigned int hex_convert (const byte **text)
-{
- unsigned int value = 0;
-
- while (is_hex (**text))
- {
- value = value * 0x10 + hex2dec (**text);
- (*text)++;
- }
-
- return value;
-}
-
-/*
- returns 1 if given character is OCT digit 0-7,
- returns 0 otherwise
-*/
-static int is_oct (byte c)
-{
- return c >= '0' && c <= '7';
-}
-
-/*
- returns value of passed character as if it was OCT digit
-*/
-static int oct2dec (byte c)
-{
- return c - '0';
-}
-
-static byte get_escape_sequence (const byte **text)
-{
- int value = 0;
-
- /* skip '\' character */
- (*text)++;
-
- switch (*(*text)++)
- {
- case '\'':
- return '\'';
- case '"':
- return '\"';
- case '?':
- return '\?';
- case '\\':
- return '\\';
- case 'a':
- return '\a';
- case 'b':
- return '\b';
- case 'f':
- return '\f';
- case 'n':
- return '\n';
- case 'r':
- return '\r';
- case 't':
- return '\t';
- case 'v':
- return '\v';
- case 'x':
- return (byte) hex_convert (text);
- }
-
- (*text)--;
- if (is_oct (**text))
- {
- value = oct2dec (*(*text)++);
- if (is_oct (**text))
- {
- value = value * 010 + oct2dec (*(*text)++);
- if (is_oct (**text))
- value = value * 010 + oct2dec (*(*text)++);
- }
- }
-
- return (byte) value;
-}
-
-/*
- copies characters from *text to *str until " or ' character is encountered,
- assumes that *str points to NULL object - caller is responsible for later freeing the string,
- assumes that *text points to " or ' character that starts the string,
- text pointer is advanced to point past the " or ' character,
- returns 0 if string was successfully copied,
- returns 1 otherwise
-*/
-static int get_string (const byte **text, byte **str)
-{
- const byte *t = *text;
- byte *p = NULL;
- unsigned int len = 0;
- byte term_char;
-
- if (string_grow (&p, &len, '\0'))
- return 1;
-
- /* read " or ' character that starts the string */
- term_char = *t++;
- /* while next character is not the terminating character */
- while (*t && *t != term_char)
- {
- byte c;
-
- if (*t == '\\')
- c = get_escape_sequence (&t);
- else
- c = *t++;
-
- if (string_grow (&p, &len, c))
- {
- mem_free ((void **) &p);
- return 1;
- }
- }
- /* skip " or ' character that ends the string */
- t++;
-
- *text = t;
- *str = p;
- return 0;
-}
-
-/*
- gets emit code, the syntax is: ".emtcode" " " <symbol> " " ("0x" | "0X") <hex_value>
- assumes that *text already points to <symbol>,
- returns 0 if emit code is successfully read,
- returns 1 otherwise
-*/
-static int get_emtcode (const byte **text, map_byte **ma)
-{
- const byte *t = *text;
- map_byte *m = NULL;
-
- map_byte_create (&m);
- if (m == NULL)
- return 1;
-
- if (get_identifier (&t, &m->key))
- {
- map_byte_destroy (&m);
- return 1;
- }
- eat_spaces (&t);
-
- if (*t == '\'')
- {
- byte *c;
-
- if (get_string (&t, &c))
- {
- map_byte_destroy (&m);
- return 1;
- }
-
- m->data = (byte) c[0];
- mem_free ((void **) &c);
- }
- else
- {
- /* skip HEX "0x" or "0X" prefix */
- t += 2;
- m->data = (byte) hex_convert (&t);
- }
-
- eat_spaces (&t);
-
- *text = t;
- *ma = m;
- return 0;
-}
-
-/*
- gets regbyte declaration, the syntax is: ".regbyte" " " <symbol> " " ("0x" | "0X") <hex_value>
- assumes that *text already points to <symbol>,
- returns 0 if regbyte is successfully read,
- returns 1 otherwise
-*/
-static int get_regbyte (const byte **text, map_byte **ma)
-{
- return get_emtcode (text, ma);
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise
-*/
-static int get_errtext (const byte **text, map_str **ma)
-{
- const byte *t = *text;
- map_str *m = NULL;
-
- map_str_create (&m);
- if (m == NULL)
- return 1;
-
- if (get_identifier (&t, &m->key))
- {
- map_str_destroy (&m);
- return 1;
- }
- eat_spaces (&t);
-
- if (get_string (&t, &m->data))
- {
- map_str_destroy (&m);
- return 1;
- }
- eat_spaces (&t);
-
- *text = t;
- *ma = m;
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int get_error (const byte **text, error **er, map_str *maps)
-{
- const byte *t = *text;
- byte *temp = NULL;
-
- if (*t != '.')
- return 0;
-
- t++;
- if (get_identifier (&t, &temp))
- return 1;
- eat_spaces (&t);
-
- if (!str_equal ((byte *) "error", temp))
- {
- mem_free ((void **) &temp);
- return 0;
- }
-
- mem_free ((void **) &temp);
-
- error_create (er);
- if (*er == NULL)
- return 1;
-
- if (*t == '\"')
- {
- if (get_string (&t, &(**er).m_text))
- {
- error_destroy (er);
- return 1;
- }
- eat_spaces (&t);
- }
- else
- {
- if (get_identifier (&t, &temp))
- {
- error_destroy (er);
- return 1;
- }
- eat_spaces (&t);
-
- if (map_str_find (&maps, temp, &(**er).m_text))
- {
- mem_free ((void **) &temp);
- error_destroy (er);
- return 1;
- }
-
- mem_free ((void **) &temp);
- }
-
- /* try to extract "token" from "...$token$..." */
- {
- byte *processed = NULL;
- unsigned int len = 0, i = 0;
-
- if (string_grow (&processed, &len, '\0'))
- {
- error_destroy (er);
- return 1;
- }
-
- while (i < str_length ((**er).m_text))
- {
- /* check if the dollar sign is repeated - if so skip it */
- if ((**er).m_text[i] == '$' && (**er).m_text[i + 1] == '$')
- {
- if (string_grow (&processed, &len, '$'))
- {
- mem_free ((void **) &processed);
- error_destroy (er);
- return 1;
- }
-
- i += 2;
- }
- else if ((**er).m_text[i] != '$')
- {
- if (string_grow (&processed, &len, (**er).m_text[i]))
- {
- mem_free ((void **) &processed);
- error_destroy (er);
- return 1;
- }
-
- i++;
- }
- else
- {
- if (string_grow (&processed, &len, '$'))
- {
- mem_free ((void **) &processed);
- error_destroy (er);
- return 1;
- }
-
- {
- /* length of token being extracted */
- unsigned int tlen = 0;
-
- if (string_grow (&(**er).m_token_name, &tlen, '\0'))
- {
- mem_free ((void **) &processed);
- error_destroy (er);
- return 1;
- }
-
- /* skip the dollar sign */
- i++;
-
- while ((**er).m_text[i] != '$')
- {
- if (string_grow (&(**er).m_token_name, &tlen, (**er).m_text[i]))
- {
- mem_free ((void **) &processed);
- error_destroy (er);
- return 1;
- }
-
- i++;
- }
-
- /* skip the dollar sign */
- i++;
- }
- }
- }
-
- mem_free ((void **) &(**er).m_text);
- (**er).m_text = processed;
- }
-
- *text = t;
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int get_emits (const byte **text, emit **em, map_byte *mapb)
-{
- const byte *t = *text;
- byte *temp = NULL;
- emit *e = NULL;
- emit_dest dest;
-
- if (*t != '.')
- return 0;
-
- t++;
- if (get_identifier (&t, &temp))
- return 1;
- eat_spaces (&t);
-
- /* .emit */
- if (str_equal ((byte *) "emit", temp))
- dest = ed_output;
- /* .load */
- else if (str_equal ((byte *) "load", temp))
- dest = ed_regbyte;
- else
- {
- mem_free ((void **) &temp);
- return 0;
- }
-
- mem_free ((void **) &temp);
-
- emit_create (&e);
- if (e == NULL)
- return 1;
-
- e->m_emit_dest = dest;
-
- if (dest == ed_regbyte)
- {
- if (get_identifier (&t, &e->m_regname))
- {
- emit_destroy (&e);
- return 1;
- }
- eat_spaces (&t);
- }
-
- /* 0xNN */
- if (*t == '0')
- {
- t += 2;
- e->m_byte = (byte) hex_convert (&t);
-
- e->m_emit_type = et_byte;
- }
- /* * */
- else if (*t == '*')
- {
- t++;
-
- e->m_emit_type = et_stream;
- }
- /* $ */
- else if (*t == '$')
- {
- t++;
-
- e->m_emit_type = et_position;
- }
- /* 'c' */
- else if (*t == '\'')
- {
- if (get_string (&t, &temp))
- {
- emit_destroy (&e);
- return 1;
- }
- e->m_byte = (byte) temp[0];
-
- mem_free ((void **) &temp);
-
- e->m_emit_type = et_byte;
- }
- else
- {
- if (get_identifier (&t, &temp))
- {
- emit_destroy (&e);
- return 1;
- }
-
- if (map_byte_find (&mapb, temp, &e->m_byte))
- {
- mem_free ((void **) &temp);
- emit_destroy (&e);
- return 1;
- }
-
- mem_free ((void **) &temp);
-
- e->m_emit_type = et_byte;
- }
-
- eat_spaces (&t);
-
- if (get_emits (&t, &e->m_next, mapb))
- {
- emit_destroy (&e);
- return 1;
- }
-
- *text = t;
- *em = e;
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int get_spec (const byte **text, spec **sp, map_str *maps, map_byte *mapb)
-{
- const byte *t = *text;
- spec *s = NULL;
-
- spec_create (&s);
- if (s == NULL)
- return 1;
-
- /* first - read optional .if statement */
- if (*t == '.')
- {
- const byte *u = t;
- byte *keyword = NULL;
-
- /* skip the dot */
- u++;
-
- if (get_identifier (&u, &keyword))
- {
- spec_destroy (&s);
- return 1;
- }
-
- /* .if */
- if (str_equal ((byte *) "if", keyword))
- {
- cond_create (&s->m_cond);
- if (s->m_cond == NULL)
- {
- spec_destroy (&s);
- return 1;
- }
-
- /* skip the left paren */
- eat_spaces (&u);
- u++;
-
- /* get the left operand */
- eat_spaces (&u);
- if (get_identifier (&u, &s->m_cond->m_operands[0].m_regname))
- {
- spec_destroy (&s);
- return 1;
- }
- s->m_cond->m_operands[0].m_type = cot_regbyte;
-
- /* get the operator (!= or ==) */
- eat_spaces (&u);
- if (*u == '!')
- s->m_cond->m_type = ct_not_equal;
- else
- s->m_cond->m_type = ct_equal;
- u += 2;
-
- /* skip the 0x prefix */
- eat_spaces (&u);
- u += 2;
-
- /* get the right operand */
- s->m_cond->m_operands[1].m_byte = hex_convert (&u);
- s->m_cond->m_operands[1].m_type = cot_byte;
-
- /* skip the right paren */
- eat_spaces (&u);
- u++;
-
- eat_spaces (&u);
-
- t = u;
- }
-
- mem_free ((void **) &keyword);
- }
-
- if (*t == '\'')
- {
- byte *temp = NULL;
-
- if (get_string (&t, &temp))
- {
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- if (*t == '-')
- {
- byte *temp2 = NULL;
-
- /* skip the '-' character */
- t++;
- eat_spaces (&t);
-
- if (get_string (&t, &temp2))
- {
- mem_free ((void **) &temp);
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- s->m_spec_type = st_byte_range;
- s->m_byte[0] = *temp;
- s->m_byte[1] = *temp2;
-
- mem_free ((void **) &temp2);
- }
- else
- {
- s->m_spec_type = st_byte;
- *s->m_byte = *temp;
- }
-
- mem_free ((void **) &temp);
- }
- else if (*t == '"')
- {
- if (get_string (&t, &s->m_string))
- {
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- s->m_spec_type = st_string;
- }
- else if (*t == '.')
- {
- byte *keyword = NULL;
-
- /* skip the dot */
- t++;
-
- if (get_identifier (&t, &keyword))
- {
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- /* .true */
- if (str_equal ((byte *) "true", keyword))
- {
- s->m_spec_type = st_true;
- }
- /* .false */
- else if (str_equal ((byte *) "false", keyword))
- {
- s->m_spec_type = st_false;
- }
- /* .debug */
- else if (str_equal ((byte *) "debug", keyword))
- {
- s->m_spec_type = st_debug;
- }
- /* .loop */
- else if (str_equal ((byte *) "loop", keyword))
- {
- if (get_identifier (&t, &s->m_string))
- {
- mem_free ((void **) &keyword);
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- s->m_spec_type = st_identifier_loop;
- }
-
- mem_free ((void **) &keyword);
- }
- else
- {
- if (get_identifier (&t, &s->m_string))
- {
- spec_destroy (&s);
- return 1;
- }
- eat_spaces (&t);
-
- s->m_spec_type = st_identifier;
- }
-
- if (get_error (&t, &s->m_errtext, maps))
- {
- spec_destroy (&s);
- return 1;
- }
-
- if (get_emits (&t, &s->m_emits, mapb))
- {
- spec_destroy (&s);
- return 1;
- }
-
- *text = t;
- *sp = s;
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int get_rule (const byte **text, rule **ru, map_str *maps, map_byte *mapb)
-{
- const byte *t = *text;
- rule *r = NULL;
-
- rule_create (&r);
- if (r == NULL)
- return 1;
-
- if (get_spec (&t, &r->m_specs, maps, mapb))
- {
- rule_destroy (&r);
- return 1;
- }
-
- while (*t != ';')
- {
- byte *op = NULL;
- spec *sp = NULL;
-
- /* skip the dot that precedes "and" or "or" */
- t++;
-
- /* read "and" or "or" keyword */
- if (get_identifier (&t, &op))
- {
- rule_destroy (&r);
- return 1;
- }
- eat_spaces (&t);
-
- if (r->m_oper == op_none)
- {
- /* .and */
- if (str_equal ((byte *) "and", op))
- r->m_oper = op_and;
- /* .or */
- else
- r->m_oper = op_or;
- }
-
- mem_free ((void **) &op);
-
- if (get_spec (&t, &sp, maps, mapb))
- {
- rule_destroy (&r);
- return 1;
- }
-
- spec_append (&r->m_specs, &sp);
- }
-
- /* skip the semicolon */
- t++;
- eat_spaces (&t);
-
- *text = t;
- *ru = r;
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int update_dependency (map_rule *mapr, byte *symbol, rule **ru)
-{
- if (map_rule_find (&mapr, symbol, ru))
- return 1;
-
-/* (**ru).m_referenced = 1; */
-
- return 0;
-}
-
-/*
- returns 0 on success,
- returns 1 otherwise,
-*/
-static int update_dependencies (dict *di, map_rule *mapr, byte **syntax_symbol,
- byte **string_symbol, map_byte *regbytes)
-{
- rule *rulez = di->m_rulez;
-
- /* update dependecies for the root and lexer symbols */
- if (update_dependency (mapr, *syntax_symbol, &di->m_syntax) ||
- (*string_symbol != NULL && update_dependency (mapr, *string_symbol, &di->m_string)))
- return 1;
-
- mem_free ((void **) syntax_symbol);
- mem_free ((void **) string_symbol);
-
- /* update dependecies for the rest of the rules */
- while (rulez)
- {
- spec *sp = rulez->m_specs;
-
- /* iterate through all the specifiers */
- while (sp)
- {
- /* update dependency for identifier */
- if (sp->m_spec_type == st_identifier || sp->m_spec_type == st_identifier_loop)
- {
- if (update_dependency (mapr, sp->m_string, &sp->m_rule))
- return 1;
-
- mem_free ((void **) &sp->m_string);
- }
-
- /* some errtexts reference to a rule */
- if (sp->m_errtext && sp->m_errtext->m_token_name)
- {
- if (update_dependency (mapr, sp->m_errtext->m_token_name, &sp->m_errtext->m_token))
- return 1;
-
- mem_free ((void **) &sp->m_errtext->m_token_name);
- }
-
- /* update dependency for condition */
- if (sp->m_cond)
- {
- int i;
- for (i = 0; i < 2; i++)
- if (sp->m_cond->m_operands[i].m_type == cot_regbyte)
- {
- sp->m_cond->m_operands[i].m_regbyte = map_byte_locate (&regbytes,
- sp->m_cond->m_operands[i].m_regname);
-
- if (sp->m_cond->m_operands[i].m_regbyte == NULL)
- return 1;
-
- mem_free ((void **) &sp->m_cond->m_operands[i].m_regname);
- }
- }
-
- /* update dependency for all .load instructions */
- if (sp->m_emits)
- {
- emit *em = sp->m_emits;
- while (em != NULL)
- {
- if (em->m_emit_dest == ed_regbyte)
- {
- em->m_regbyte = map_byte_locate (&regbytes, em->m_regname);
-
- if (em->m_regbyte == NULL)
- return 1;
-
- mem_free ((void **) &em->m_regname);
- }
-
- em = em->m_next;
- }
- }
-
- sp = sp->m_next;
- }
-
- rulez = rulez->m_next;
- }
-
-/* check for unreferenced symbols */
-/* de = di->m_defntns;
- while (de)
- {
- if (!de->m_referenced)
- {
- map_def *ma = mapd;
- while (ma)
- {
- if (ma->data == de)
- {
- assert (0);
- break;
- }
- ma = ma->next;
- }
- }
- de = de->m_next;
- }
-*/
- return 0;
-}
-
-static int satisfies_condition (cond *co, regbyte_ctx *ctx)
-{
- byte values[2];
- int i;
-
- if (co == NULL)
- return 1;
-
- for (i = 0; i < 2; i++)
- switch (co->m_operands[i].m_type)
- {
- case cot_byte:
- values[i] = co->m_operands[i].m_byte;
- break;
- case cot_regbyte:
- values[i] = regbyte_ctx_extract (&ctx, co->m_operands[i].m_regbyte);
- break;
- }
-
- switch (co->m_type)
- {
- case ct_equal:
- return values[0] == values[1];
- case ct_not_equal:
- return values[0] != values[1];
- }
-
- return 0;
-}
-
-static void free_regbyte_ctx_stack (regbyte_ctx *top, regbyte_ctx *limit)
-{
- while (top != limit)
- {
- regbyte_ctx *rbc = top->m_prev;
- regbyte_ctx_destroy (&top);
- top = rbc;
- }
-}
-
-typedef enum match_result_
-{
- mr_not_matched, /* the examined string does not match */
- mr_matched, /* the examined string matches */
- mr_error_raised, /* mr_not_matched + error has been raised */
- mr_dont_emit, /* used by identifier loops only */
- mr_internal_error /* an internal error has occured such as out of memory */
-} match_result;
-
-/*
- This function does the main job. It parses the text and generates output data.
-
- XXX optimize it - the barray seems to be the bottleneck
-*/
-static match_result match (dict *di, const byte *text, unsigned int *index, rule *ru, barray **ba,
- int filtering_string, regbyte_ctx **rbc)
-{
- unsigned int ind = *index;
- match_result status = mr_not_matched;
- spec *sp = ru->m_specs;
- regbyte_ctx *ctx = *rbc;
-
- /* for every specifier in the rule */
- while (sp)
- {
- unsigned int i, len, save_ind = ind;
- barray *array = NULL;
-
- if (satisfies_condition (sp->m_cond, ctx))
- {
- switch (sp->m_spec_type)
- {
- case st_identifier:
- barray_create (&array);
- if (array == NULL)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- return mr_internal_error;
- }
-
- status = match (di, text, &ind, sp->m_rule, &array, filtering_string, &ctx);
- if (status == mr_internal_error)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
- return mr_internal_error;
- }
- break;
- case st_string:
- len = str_length (sp->m_string);
-
- /* prefilter the stream */
- if (!filtering_string && di->m_string)
- {
- barray *ba;
- unsigned int filter_index = 0;
- match_result result;
- regbyte_ctx *null_ctx = NULL;
-
- barray_create (&ba);
- if (ba == NULL)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- return mr_internal_error;
- }
-
- result = match (di, text + ind, &filter_index, di->m_string, &ba, 1, &null_ctx);
-
- if (result == mr_internal_error)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&ba);
- return mr_internal_error;
- }
-
- if (result != mr_matched)
- {
- barray_destroy (&ba);
- status = mr_not_matched;
- break;
- }
-
- barray_destroy (&ba);
-
- if (filter_index != len || !str_equal_n (sp->m_string, text + ind, len))
- {
- status = mr_not_matched;
- break;
- }
-
- status = mr_matched;
- ind += len;
- }
- else
- {
- status = mr_matched;
- for (i = 0; status == mr_matched && i < len; i++)
- if (text[ind + i] != sp->m_string[i])
- status = mr_not_matched;
- if (status == mr_matched)
- ind += len;
- }
- break;
- case st_byte:
- status = text[ind] == *sp->m_byte ? mr_matched : mr_not_matched;
- if (status == mr_matched)
- ind++;
- break;
- case st_byte_range:
- status = (text[ind] >= sp->m_byte[0] && text[ind] <= sp->m_byte[1]) ?
- mr_matched : mr_not_matched;
- if (status == mr_matched)
- ind++;
- break;
- case st_true:
- status = mr_matched;
- break;
- case st_false:
- status = mr_not_matched;
- break;
- case st_debug:
- status = ru->m_oper == op_and ? mr_matched : mr_not_matched;
- break;
- case st_identifier_loop:
- barray_create (&array);
- if (array == NULL)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- return mr_internal_error;
- }
-
- status = mr_dont_emit;
- for (;;)
- {
- match_result result;
-
- save_ind = ind;
- result = match (di, text, &ind, sp->m_rule, &array, filtering_string, &ctx);
-
- if (result == mr_error_raised)
- {
- status = result;
- break;
- }
- else if (result == mr_matched)
- {
- if (barray_push (ba, sp->m_emits, text[ind - 1], save_ind, &ctx) ||
- barray_append (ba, &array))
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
- return mr_internal_error;
- }
- barray_destroy (&array);
- barray_create (&array);
- if (array == NULL)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- return mr_internal_error;
- }
- }
- else if (result == mr_internal_error)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
- return mr_internal_error;
- }
- else
- break;
- }
- break;
- }
- }
- else
- {
- status = mr_not_matched;
- }
-
- if (status == mr_error_raised)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
-
- return mr_error_raised;
- }
-
- if (ru->m_oper == op_and && status != mr_matched && status != mr_dont_emit)
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
-
- if (sp->m_errtext)
- {
- set_last_error (sp->m_errtext->m_text, error_get_token (sp->m_errtext, di, text,
- ind), ind);
-
- return mr_error_raised;
- }
-
- return mr_not_matched;
- }
-
- if (status == mr_matched)
- {
- if (sp->m_emits)
- if (barray_push (ba, sp->m_emits, text[ind - 1], save_ind, &ctx))
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
- return mr_internal_error;
- }
-
- if (array)
- if (barray_append (ba, &array))
- {
- free_regbyte_ctx_stack (ctx, *rbc);
- barray_destroy (&array);
- return mr_internal_error;
- }
- }
-
- barray_destroy (&array);
-
- /* if the rule operator is a logical or, we pick up the first matching specifier */
- if (ru->m_oper == op_or && (status == mr_matched || status == mr_dont_emit))
- {
- *index = ind;
- *rbc = ctx;
- return mr_matched;
- }
-
- sp = sp->m_next;
- }
-
- /* everything went fine - all specifiers match up */
- if (ru->m_oper == op_and && (status == mr_matched || status == mr_dont_emit))
- {
- *index = ind;
- *rbc = ctx;
- return mr_matched;
- }
-
- free_regbyte_ctx_stack (ctx, *rbc);
- return mr_not_matched;
-}
-
-static byte *error_get_token (error *er, dict *di, const byte *text, unsigned int ind)
-{
- byte *str = NULL;
-
- if (er->m_token)
- {
- barray *ba;
- unsigned int filter_index = 0;
- regbyte_ctx *ctx = NULL;
-
- barray_create (&ba);
- if (ba != NULL)
- {
- if (match (di, text + ind, &filter_index, er->m_token, &ba, 0, &ctx) == mr_matched &&
- filter_index)
- {
- str = mem_alloc (filter_index + 1);
- if (str != NULL)
- {
- str_copy_n (str, text + ind, filter_index);
- str[filter_index] = '\0';
- }
- }
- barray_destroy (&ba);
- }
- }
-
- return str;
-}
-
-typedef struct grammar_load_state_
-{
- dict *di;
- byte *syntax_symbol;
- byte *string_symbol;
- map_str *maps;
- map_byte *mapb;
- map_rule *mapr;
-} grammar_load_state;
-
-static void grammar_load_state_create (grammar_load_state **gr)
-{
- *gr = mem_alloc (sizeof (grammar_load_state));
- if (*gr)
- {
- (**gr).di = NULL;
- (**gr).syntax_symbol = NULL;
- (**gr).string_symbol = NULL;
- (**gr).maps = NULL;
- (**gr).mapb = NULL;
- (**gr).mapr = NULL;
- }
-}
-
-static void grammar_load_state_destroy (grammar_load_state **gr)
-{
- if (*gr)
- {
- dict_destroy (&(**gr).di);
- mem_free ((void **) &(**gr).syntax_symbol);
- mem_free ((void **) &(**gr).string_symbol);
- map_str_destroy (&(**gr).maps);
- map_byte_destroy (&(**gr).mapb);
- map_rule_destroy (&(**gr).mapr);
- mem_free ((void **) gr);
- }
-}
-
-/*
- the API
-*/
-
-grammar grammar_load_from_text (const byte *text)
-{
- grammar_load_state *g = NULL;
- grammar id = 0;
-
- clear_last_error ();
-
- grammar_load_state_create (&g);
- if (g == NULL)
- return 0;
-
- dict_create (&g->di);
- if (g->di == NULL)
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- eat_spaces (&text);
-
- /* skip ".syntax" keyword */
- text += 7;
- eat_spaces (&text);
-
- /* retrieve root symbol */
- if (get_identifier (&text, &g->syntax_symbol))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
- eat_spaces (&text);
-
- /* skip semicolon */
- text++;
- eat_spaces (&text);
-
- while (*text)
- {
- byte *symbol = NULL;
- int is_dot = *text == '.';
-
- if (is_dot)
- text++;
-
- if (get_identifier (&text, &symbol))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
- eat_spaces (&text);
-
- /* .emtcode */
- if (is_dot && str_equal (symbol, (byte *) "emtcode"))
- {
- map_byte *ma = NULL;
-
- mem_free ((void **) &symbol);
-
- if (get_emtcode (&text, &ma))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- map_byte_append (&g->mapb, &ma);
- }
- /* .regbyte */
- else if (is_dot && str_equal (symbol, (byte *) "regbyte"))
- {
- map_byte *ma = NULL;
-
- mem_free ((void **) &symbol);
-
- if (get_regbyte (&text, &ma))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- map_byte_append (&g->di->m_regbytes, &ma);
- }
- /* .errtext */
- else if (is_dot && str_equal (symbol, (byte *) "errtext"))
- {
- map_str *ma = NULL;
-
- mem_free ((void **) &symbol);
-
- if (get_errtext (&text, &ma))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- map_str_append (&g->maps, &ma);
- }
- /* .string */
- else if (is_dot && str_equal (symbol, (byte *) "string"))
- {
- mem_free ((void **) &symbol);
-
- if (g->di->m_string != NULL)
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- if (get_identifier (&text, &g->string_symbol))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- /* skip semicolon */
- eat_spaces (&text);
- text++;
- eat_spaces (&text);
- }
- else
- {
- rule *ru = NULL;
- map_rule *ma = NULL;
-
- if (get_rule (&text, &ru, g->maps, g->mapb))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- rule_append (&g->di->m_rulez, &ru);
-
- /* if a rule consist of only one specifier, give it an ".and" operator */
- if (ru->m_oper == op_none)
- ru->m_oper = op_and;
-
- map_rule_create (&ma);
- if (ma == NULL)
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- ma->key = symbol;
- ma->data = ru;
- map_rule_append (&g->mapr, &ma);
- }
- }
-
- if (update_dependencies (g->di, g->mapr, &g->syntax_symbol, &g->string_symbol,
- g->di->m_regbytes))
- {
- grammar_load_state_destroy (&g);
- return 0;
- }
-
- dict_append (&g_dicts, &g->di);
- id = g->di->m_id;
- g->di = NULL;
-
- grammar_load_state_destroy (&g);
-
- return id;
-}
-
-int grammar_set_reg8 (grammar id, const byte *name, byte value)
-{
- dict *di = NULL;
- map_byte *reg = NULL;
-
- clear_last_error ();
-
- dict_find (&g_dicts, id, &di);
- if (di == NULL)
- {
- set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
- return 0;
- }
-
- reg = map_byte_locate (&di->m_regbytes, name);
- if (reg == NULL)
- {
- set_last_error (INVALID_REGISTER_NAME, str_duplicate (name), -1);
- return 0;
- }
-
- reg->data = value;
- return 1;
-}
-
-int grammar_check (grammar id, const byte *text, byte **prod, unsigned int *size)
-{
- dict *di = NULL;
- barray *ba = NULL;
- unsigned int index = 0;
- regbyte_ctx *rbc = NULL;
-
- clear_last_error ();
-
- dict_find (&g_dicts, id, &di);
- if (di == NULL)
- {
- set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
- return 0;
- }
-
- barray_create (&ba);
- if (ba == NULL)
- return 0;
-
- *prod = NULL;
- *size = 0;
-
- if (match (di, text, &index, di->m_syntax, &ba, 0, &rbc) != mr_matched)
- {
- barray_destroy (&ba);
- free_regbyte_ctx_stack (rbc, NULL);
- return 0;
- }
-
- free_regbyte_ctx_stack (rbc, NULL);
-
- *prod = mem_alloc (ba->len * sizeof (byte));
- if (*prod == NULL)
- {
- barray_destroy (&ba);
- return 0;
- }
-
- mem_copy (*prod, ba->data, ba->len * sizeof (byte));
- *size = ba->len;
- barray_destroy (&ba);
-
- return 1;
-}
-
-int grammar_destroy (grammar id)
-{
- dict **di = &g_dicts;
-
- clear_last_error ();
-
- while (*di != NULL)
- {
- if ((**di).m_id == id)
- {
- dict *tmp = *di;
- *di = (**di).m_next;
- dict_destroy (&tmp);
- return 1;
- }
-
- di = &(**di).m_next;
- }
-
- set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
- return 0;
-}
-
-void grammar_get_last_error (byte *text, unsigned int size, int *pos)
-{
- unsigned int len = 0, dots_made = 0;
- const byte *p = error_message;
-
- *text = '\0';
-
-#define APPEND_CHARACTER(x) if (dots_made == 0) {\
- if (len < size - 1) {\
- text[len++] = (x); text[len] = '\0';\
- } else {\
- int i;\
- for (i = 0; i < 3; i++)\
- if (--len >= 0)\
- text[len] = '.';\
- dots_made = 1;\
- }\
- }
-
- if (p)
- while (*p)
- if (*p == '$')
- {
- const byte *r = error_param;
-
- while (*r)
- {
- APPEND_CHARACTER(*r)
- r++;
- }
-
- p++;
- }
- else
- {
- APPEND_CHARACTER(*p)
- p++;
- }
-
- *pos = error_position;
-
-#undef APPEND_CHARACTER
-
-}
-
+/*
+ * Mesa 3-D graphics library
+ * Version: 6.1
+ *
+ * Copyright (C) 1999-2004 Brian Paul All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file grammar.c
+ * syntax parsing engine
+ * \author Michal Krol
+ */
+
+#ifndef GRAMMAR_PORT_BUILD
+#error Do not build this file directly, build your grammar_XXX.c instead, which includes this file
+#endif
+
+/*
+ Last Modified: 2004-II-8
+*/
+
+/*
+ INTRODUCTION
+ ------------
+
+ The task is to check the syntax of an input string. Input string is a stream of ASCII
+ characters terminated with a null-character ('\0'). Checking it using C language is
+ difficult and hard to implement without bugs. It is hard to maintain and make changes when
+ the syntax changes.
+
+ This is because of a high redundancy of the C code. Large blocks of code are duplicated with
+ only small changes. Even use of macros does not solve the problem because macros cannot
+ erase the complexity of the problem.
+
+ The resolution is to create a new language that will be highly oriented to our task. Once
+ we describe a particular syntax, we are done. We can then focus on the code that implements
+ the language. The size and complexity of it is relatively small than the code that directly
+ checks the syntax.
+
+ First, we must implement our new language. Here, the language is implemented in C, but it
+ could also be implemented in any other language. The code is listed below. We must take
+ a good care that it is bug free. This is simple because the code is simple and clean.
+
+ Next, we must describe the syntax of our new language in itself. Once created and checked
+ manually that it is correct, we can use it to check another scripts.
+
+ Note that our new language loading code does not have to check the syntax. It is because we
+ assume that the script describing itself is correct, and other scripts can be syntactically
+ checked by the former script. The loading code must only do semantic checking which leads us to
+ simple resolving references.
+
+ THE LANGUAGE
+ ------------
+
+ Here I will describe the syntax of the new language (further called "Synek"). It is mainly a
+ sequence of declarations terminated by a semicolon. The declaration consists of a symbol,
+ which is an identifier, and its definition. A definition is in turn a sequence of specifiers
+ connected with ".and" or ".or" operator. These operators cannot be mixed together in a one
+ definition. Specifier can be a symbol, string, character, character range or a special
+ keyword ".true" or ".false".
+
+ On the very beginning of the script there is a declaration of a root symbol and is in the form:
+ .syntax <root_symbol>;
+ The <root_symbol> must be on of the symbols in declaration sequence. The syntax is correct if
+ the root symbol evaluates to true. A symbol evaluates to true if the definition associated with
+ the symbol evaluates to true. Definition evaluation depends on the operator used to connect
+ specifiers in the definition. If ".and" operator is used, definition evaluates to true if and
+ only if all the specifiers evaluate to true. If ".or" operator is used, definition evalutes to
+ true if any of the specifiers evaluates to true. If definition contains only one specifier,
+ it is evaluated as if it was connected with ".true" keyword by ".and" operator.
+
+ If specifier is a ".true" keyword, it always evaluates to true.
+
+ If specifier is a ".false" keyword, it always evaluates to false. Specifier evaluates to false
+ when it does not evaluate to true.
+
+ Character range specifier is in the form:
+ '<first_character>' - '<second_character>'
+ If specifier is a character range, it evaluates to true if character in the stream is greater
+ or equal to <first_character> and less or equal to <second_character>. In that situation
+ the stream pointer is advanced to point to next character in the stream. All C-style escape
+ sequences are supported although trigraph sequences are not. The comparisions are performed
+ on 8-bit unsigned integers.
+
+ Character specifier is in the form:
+ '<single_character>'
+ It evaluates to true if the following character range specifier evaluates to true:
+ '<single_character>' - '<single_character>'
+
+ String specifier is in the form:
+ "<string>"
+ Let N be the number of characters in <string>. Let <string>[i] designate i-th character in
+ <string>. Then the string specifier evaluates to true if and only if for i in the range [0, N)
+ the following character specifier evaluates to true:
+ '<string>[i]'
+ If <string>[i] is a quotation mark, '<string>[i]' is replaced with '\<string>[i]'.
+
+ Symbol specifier can be optionally preceded by a ".loop" keyword in the form:
+ .loop <symbol> (1)
+ where <symbol> is defined as follows:
+ <symbol> <definition>; (2)
+ Construction (1) is replaced by the following code:
+ <symbol$1>
+ and declaration (2) is replaced by the following:
+ <symbol$1> <symbol$2> .or .true;
+ <symbol$2> <symbol> .and <symbol$1>;
+ <symbol> <definition>;
+
+ Synek supports also a register mechanizm. User can, in its SYN file, declare a number of
+ registers that can be accessed in the syn body. Each reg has its name and a default value.
+ The register is one byte wide. The C code can change the default value by calling
+ grammar_set_reg8() with grammar id, register name and a new value. As we know, each rule is
+ a sequence of specifiers joined with .and or .or operator. And now each specifier can be
+ prefixed with a condition expression in a form ".if (<reg_name> <operator> <hex_literal>)"
+ where <operator> can be == or !=. If the condition evaluates to false, the specifier
+ evaluates to .false. Otherwise it evalutes to the specifier.
+
+ ESCAPE SEQUENCES
+ ----------------
+
+ Synek supports all escape sequences in character specifiers. The mapping table is listed below.
+ All occurences of the characters in the first column are replaced with the corresponding
+ character in the second column.
+
+ Escape sequence Represents
+ ------------------------------------------------------------------------------------------------
+ \a Bell (alert)
+ \b Backspace
+ \f Formfeed
+ \n New line
+ \r Carriage return
+ \t Horizontal tab
+ \v Vertical tab
+ \' Single quotation mark
+ \" Double quotation mark
+ \\ Backslash
+ \? Literal question mark
+ \ooo ASCII character in octal notation
+ \xhhh ASCII character in hexadecimal notation
+ ------------------------------------------------------------------------------------------------
+
+ RAISING ERRORS
+ --------------
+
+ Any specifier can be followed by a special construction that is executed when the specifier
+ evaluates to false. The construction is in the form:
+ .error <ERROR_TEXT>
+ <ERROR_TEXT> is an identifier declared earlier by error text declaration. The declaration is
+ in the form:
+ .errtext <ERROR_TEXT> "<error_desc>"
+ When specifier evaluates to false and this construction is present, parsing is stopped
+ immediately and <error_desc> is returned as a result of parsing. The error position is also
+ returned and it is meant as an offset from the beggining of the stream to the character that
+ was valid so far. Example:
+
+ (**** syntax script ****)
+
+ .syntax program;
+ .errtext MISSING_SEMICOLON "missing ';'"
+ program declaration .and .loop space .and ';' .error MISSING_SEMICOLON .and
+ .loop space .and '\0';
+ declaration "declare" .and .loop space .and identifier;
+ space ' ';
+
+ (**** sample code ****)
+
+ declare foo ,
+
+ In the example above checking the sample code will result in error message "missing ';'" and
+ error position 12. The sample code is not correct. Note the presence of '\0' specifier to
+ assure that there is no code after semicolon - only spaces.
+ <error_desc> can optionally contain identifier surrounded by dollar signs $. In such a case,
+ the identifier and dollar signs are replaced by a string retrieved by invoking symbol with
+ the identifier name. The starting position is the error position. The lenght of the resulting
+ string is the position after invoking the symbol.
+
+ PRODUCTION
+ ----------
+
+ Synek not only checks the syntax but it can also produce (emit) bytes associated with specifiers
+ that evaluate to true. That is, every specifier and optional error construction can be followed
+ by a number of emit constructions that are in the form:
+ .emit <parameter>
+ <paramater> can be a HEX number, identifier, a star * or a dollar $. HEX number is preceded by
+ 0x or 0X. If <parameter> is an identifier, it must be earlier declared by emit code declaration
+ in the form:
+ .emtcode <identifier> <hex_number>
+
+ When given specifier evaluates to true, all emits associated with the specifier are output
+ in order they were declared. A star means that last-read character should be output instead
+ of constant value. Example:
+
+ (**** syntax script ****)
+
+ .syntax foobar;
+ .emtcode WORD_FOO 0x01
+ .emtcode WORD_BAR 0x02
+ foobar FOO .emit WORD_FOO .or BAR .emit WORD_BAR .or .true .emit 0x00;
+ FOO "foo" .and SPACE;
+ BAR "bar" .and SPACE;
+ SPACE ' ' .or '\0';
+
+ (**** sample text 1 ****)
+
+ foo
+
+ (**** sample text 2 ****)
+
+ foobar
+
+ For both samples the result will be one-element array. For first sample text it will be
+ value 1, for second - 0. Note that every text will be accepted because of presence of
+ .true as an alternative.
+
+ Another example:
+
+ (**** syntax script ****)
+
+ .syntax declaration;
+ .emtcode VARIABLE 0x01
+ declaration "declare" .and .loop space .and
+ identifier .emit VARIABLE .and (1)
+ .true .emit 0x00 .and (2)
+ .loop space .and ';';
+ space ' ' .or '\t';
+ identifier .loop id_char .emit *; (3)
+ id_char 'a'-'z' .or 'A'-'Z' .or '_';
+
+ (**** sample code ****)
+
+ declare fubar;
+
+ In specifier (1) symbol <identifier> is followed by .emit VARIABLE. If it evaluates to
+ true, VARIABLE constant and then production of the symbol is output. Specifier (2) is used
+ to terminate the string with null to signal when the string ends. Specifier (3) outputs
+ all characters that make declared identifier. The result of sample code will be the
+ following array:
+ { 1, 'f', 'u', 'b', 'a', 'r', 0 }
+
+ If .emit is followed by dollar $, it means that current position should be output. Current
+ position is a 32-bit unsigned integer distance from the very beginning of the parsed string to
+ first character consumed by the specifier associated with the .emit instruction. Current
+ position is stored in the output buffer in Little-Endian convention (the lowest byte comes
+ first).
+*/
+
+static void mem_free (void **);
+
+/*
+ internal error messages
+*/
+static const byte *OUT_OF_MEMORY = (byte *) "internal error 1001: out of physical memory";
+static const byte *UNRESOLVED_REFERENCE = (byte *) "internal error 1002: unresolved reference '$'";
+static const byte *INVALID_GRAMMAR_ID = (byte *) "internal error 1003: invalid grammar object";
+static const byte *INVALID_REGISTER_NAME = (byte *) "internal error 1004: invalid register name: '$'";
+
+static const byte *error_message = NULL;
+static byte *error_param = NULL; /* this is inserted into error_message in place of $ */
+static int error_position = -1;
+
+static byte *unknown = (byte *) "???";
+
+static void clear_last_error ()
+{
+ /* reset error message */
+ error_message = NULL;
+
+ /* free error parameter - if error_param is a "???" don't free it - it's static */
+ if (error_param != unknown)
+ mem_free ((void **) &error_param);
+ else
+ error_param = NULL;
+
+ /* reset error position */
+ error_position = -1;
+}
+
+static void set_last_error (const byte *msg, byte *param, int pos)
+{
+ /* error message can only be set only once */
+ if (error_message != NULL)
+ {
+ mem_free (&param);
+ return;
+ }
+
+ error_message = msg;
+
+ if (param != NULL)
+ error_param = param;
+ else
+ error_param = unknown;
+
+ error_position = pos;
+}
+
+/*
+ memory management routines
+*/
+static void *mem_alloc (size_t size)
+{
+ void *ptr = grammar_alloc_malloc (size);
+ if (ptr == NULL)
+ set_last_error (OUT_OF_MEMORY, NULL, -1);
+ return ptr;
+}
+
+static void *mem_copy (void *dst, const void *src, size_t size)
+{
+ return grammar_memory_copy (dst, src, size);
+}
+
+static void mem_free (void **ptr)
+{
+ grammar_alloc_free (*ptr);
+ *ptr = NULL;
+}
+
+static void *mem_realloc (void *ptr, size_t old_size, size_t new_size)
+{
+ void *ptr2 = grammar_alloc_realloc (ptr, old_size, new_size);
+ if (ptr2 == NULL)
+ set_last_error (OUT_OF_MEMORY, NULL, -1);
+ return ptr2;
+}
+
+static byte *str_copy_n (byte *dst, const byte *src, size_t max_len)
+{
+ return grammar_string_copy_n (dst, src, max_len);
+}
+
+static byte *str_duplicate (const byte *str)
+{
+ byte *new_str = grammar_string_duplicate (str);
+ if (new_str == NULL)
+ set_last_error (OUT_OF_MEMORY, NULL, -1);
+ return new_str;
+}
+
+static int str_equal (const byte *str1, const byte *str2)
+{
+ return grammar_string_compare (str1, str2) == 0;
+}
+
+static int str_equal_n (const byte *str1, const byte *str2, unsigned int n)
+{
+ return grammar_string_compare_n (str1, str2, n) == 0;
+}
+
+static unsigned int str_length (const byte *str)
+{
+ return grammar_string_length (str);
+}
+
+/*
+ string to byte map typedef
+*/
+typedef struct map_byte_
+{
+ byte *key;
+ byte data;
+ struct map_byte_ *next;
+} map_byte;
+
+static void map_byte_create (map_byte **ma)
+{
+ *ma = mem_alloc (sizeof (map_byte));
+ if (*ma)
+ {
+ (**ma).key = NULL;
+ (**ma).data = '\0';
+ (**ma).next = NULL;
+ }
+}
+
+/* XXX unfold the recursion */
+static void map_byte_destroy (map_byte **ma)
+{
+ if (*ma)
+ {
+ map_byte_destroy (&(**ma).next);
+ mem_free ((void **) &(**ma).key);
+ mem_free ((void **) ma);
+ }
+}
+
+static void map_byte_append (map_byte **ma, map_byte **nm)
+{
+ while (*ma)
+ ma = &(**ma).next;
+ *ma = *nm;
+}
+
+/*
+ searches the map for the specified key,
+ returns pointer to the element with the specified key if it exists
+ returns NULL otherwise
+*/
+map_byte *map_byte_locate (map_byte **ma, const byte *key)
+{
+ while (*ma)
+ {
+ if (str_equal ((**ma).key, key))
+ return *ma;
+
+ ma = &(**ma).next;
+ }
+
+ set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
+ return NULL;
+}
+
+/*
+ searches the map for specified key,
+ if the key is matched, *data is filled with data associated with the key,
+ returns 0 if the key is matched,
+ returns 1 otherwise
+*/
+static int map_byte_find (map_byte **ma, const byte *key, byte *data)
+{
+ map_byte *found = map_byte_locate (ma, key);
+ if (found != NULL)
+ {
+ *data = found->data;
+
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ regbyte context typedef
+
+ Each regbyte consists of its name and a default value. These are static and created at
+ grammar script compile-time, for example the following line:
+ .regbyte vertex_blend 0x00
+ adds a new regbyte named "vertex_blend" to the static list and initializes it to 0.
+ When the script is executed, this regbyte can be accessed by name for read and write. When a
+ particular regbyte is written, a new regbyte_ctx entry is added to the top of the regbyte_ctx
+ stack. The new entry contains information abot which regbyte it references and its new value.
+ When a given regbyte is accessed for read, the stack is searched top-down to find an
+ entry that references the regbyte. The first matching entry is used to return the current
+ value it holds. If no entry is found, the default value is returned.
+*/
+typedef struct regbyte_ctx_
+{
+ map_byte *m_regbyte;
+ byte m_current_value;
+ struct regbyte_ctx_ *m_prev;
+} regbyte_ctx;
+
+static void regbyte_ctx_create (regbyte_ctx **re)
+{
+ *re = mem_alloc (sizeof (regbyte_ctx));
+ if (*re)
+ {
+ (**re).m_regbyte = NULL;
+ (**re).m_prev = NULL;
+ }
+}
+
+static void regbyte_ctx_destroy (regbyte_ctx **re)
+{
+ if (*re)
+ {
+ mem_free ((void **) re);
+ }
+}
+
+static byte regbyte_ctx_extract (regbyte_ctx **re, map_byte *reg)
+{
+ /* first lookup in the register stack */
+ while (*re != NULL)
+ {
+ if ((**re).m_regbyte == reg)
+ return (**re).m_current_value;
+
+ re = &(**re).m_prev;
+ }
+
+ /* if not found - return the default value */
+ return reg->data;
+}
+
+/*
+ emit type typedef
+*/
+typedef enum emit_type_
+{
+ et_byte, /* explicit number */
+ et_stream, /* eaten character */
+ et_position /* current position */
+} emit_type;
+
+/*
+ emit destination typedef
+*/
+typedef enum emit_dest_
+{
+ ed_output, /* write to the output buffer */
+ ed_regbyte /* write a particular regbyte */
+} emit_dest;
+
+/*
+ emit typedef
+*/
+typedef struct emit_
+{
+ emit_dest m_emit_dest;
+ emit_type m_emit_type; /* ed_output */
+ byte m_byte; /* et_byte */
+ map_byte *m_regbyte; /* ed_regbyte */
+ byte *m_regname; /* ed_regbyte - temporary */
+ struct emit_ *m_next;
+} emit;
+
+static void emit_create (emit **em)
+{
+ *em = mem_alloc (sizeof (emit));
+ if (*em)
+ {
+ (**em).m_emit_dest = ed_output;
+ (**em).m_emit_type = et_byte;
+ (**em).m_byte = '\0';
+ (**em).m_regbyte = NULL;
+ (**em).m_regname = NULL;
+ (**em).m_next = NULL;
+ }
+}
+
+static void emit_destroy (emit **em)
+{
+ if (*em)
+ {
+ emit_destroy (&(**em).m_next);
+ mem_free ((void **) &(**em).m_regname);
+ mem_free ((void **) em);
+ }
+}
+
+/*
+ error typedef
+*/
+typedef struct error_
+{
+ byte *m_text;
+ byte *m_token_name;
+ struct rule_ *m_token;
+} error;
+
+static void error_create (error **er)
+{
+ *er = mem_alloc (sizeof (error));
+ if (*er)
+ {
+ (**er).m_text = NULL;
+ (**er).m_token_name = NULL;
+ (**er).m_token = NULL;
+ }
+}
+
+static void error_destroy (error **er)
+{
+ if (*er)
+ {
+ mem_free ((void **) &(**er).m_text);
+ mem_free ((void **) &(**er).m_token_name);
+ mem_free ((void **) er);
+ }
+}
+
+struct dict_;
+static byte *error_get_token (error *, struct dict_ *, const byte *, unsigned int);
+
+/*
+ condition operand type typedef
+*/
+typedef enum cond_oper_type_
+{
+ cot_byte, /* constant 8-bit unsigned integer */
+ cot_regbyte /* pointer to byte register containing the current value */
+} cond_oper_type;
+
+/*
+ condition operand typedef
+*/
+typedef struct cond_oper_
+{
+ cond_oper_type m_type;
+ byte m_byte; /* cot_byte */
+ map_byte *m_regbyte; /* cot_regbyte */
+ byte *m_regname; /* cot_regbyte - temporary */
+} cond_oper;
+
+/*
+ condition type typedef
+*/
+typedef enum cond_type_
+{
+ ct_equal,
+ ct_not_equal
+} cond_type;
+
+/*
+ condition typedef
+*/
+typedef struct cond_
+{
+ cond_type m_type;
+ cond_oper m_operands[2];
+} cond;
+
+static void cond_create (cond **co)
+{
+ *co = mem_alloc (sizeof (cond));
+ if (*co)
+ {
+ (**co).m_operands[0].m_regname = NULL;
+ (**co).m_operands[1].m_regname = NULL;
+ }
+}
+
+static void cond_destroy (cond **co)
+{
+ if (*co)
+ {
+ mem_free ((void **) &(**co).m_operands[0].m_regname);
+ mem_free ((void **) &(**co).m_operands[1].m_regname);
+ mem_free ((void **) co);
+ }
+}
+
+/*
+ specifier type typedef
+*/
+typedef enum spec_type_
+{
+ st_false,
+ st_true,
+ st_byte,
+ st_byte_range,
+ st_string,
+ st_identifier,
+ st_identifier_loop,
+ st_debug
+} spec_type;
+
+/*
+ specifier typedef
+*/
+typedef struct spec_
+{
+ spec_type m_spec_type;
+ byte m_byte[2]; /* st_byte, st_byte_range */
+ byte *m_string; /* st_string */
+ struct rule_ *m_rule; /* st_identifier, st_identifier_loop */
+ emit *m_emits;
+ error *m_errtext;
+ cond *m_cond;
+ struct spec_ *m_next;
+} spec;
+
+static void spec_create (spec **sp)
+{
+ *sp = mem_alloc (sizeof (spec));
+ if (*sp)
+ {
+ (**sp).m_spec_type = st_false;
+ (**sp).m_byte[0] = '\0';
+ (**sp).m_byte[1] = '\0';
+ (**sp).m_string = NULL;
+ (**sp).m_rule = NULL;
+ (**sp).m_emits = NULL;
+ (**sp).m_errtext = NULL;
+ (**sp).m_cond = NULL;
+ (**sp).m_next = NULL;
+ }
+}
+
+static void spec_destroy (spec **sp)
+{
+ if (*sp)
+ {
+ spec_destroy (&(**sp).m_next);
+ emit_destroy (&(**sp).m_emits);
+ error_destroy (&(**sp).m_errtext);
+ mem_free ((void **) &(**sp).m_string);
+ cond_destroy (&(**sp).m_cond);
+ mem_free ((void **) sp);
+ }
+}
+
+static void spec_append (spec **sp, spec **ns)
+{
+ while (*sp)
+ sp = &(**sp).m_next;
+ *sp = *ns;
+}
+
+/*
+ operator typedef
+*/
+typedef enum oper_
+{
+ op_none,
+ op_and,
+ op_or
+} oper;
+
+/*
+ rule typedef
+*/
+typedef struct rule_
+{
+ oper m_oper;
+ spec *m_specs;
+ struct rule_ *m_next;
+/* int m_referenced; */ /* for debugging purposes */
+} rule;
+
+static void rule_create (rule **ru)
+{
+ *ru = mem_alloc (sizeof (rule));
+ if (*ru)
+ {
+ (**ru).m_oper = op_none;
+ (**ru).m_specs = NULL;
+ (**ru).m_next = NULL;
+/* (**ru).m_referenced = 0; */
+ }
+}
+
+static void rule_destroy (rule **ru)
+{
+ if (*ru)
+ {
+ rule_destroy (&(**ru).m_next);
+ spec_destroy (&(**ru).m_specs);
+ mem_free ((void **) ru);
+ }
+}
+
+static void rule_append (rule **ru, rule **nr)
+{
+ while (*ru)
+ ru = &(**ru).m_next;
+ *ru = *nr;
+}
+
+/*
+ returns unique grammar id
+*/
+static grammar next_valid_grammar_id ()
+{
+ static grammar id = 0;
+
+ return ++id;
+}
+
+/*
+ dictionary typedef
+*/
+typedef struct dict_
+{
+ rule *m_rulez;
+ rule *m_syntax;
+ rule *m_string;
+ map_byte *m_regbytes;
+ grammar m_id;
+ struct dict_ *m_next;
+} dict;
+
+static void dict_create (dict **di)
+{
+ *di = mem_alloc (sizeof (dict));
+ if (*di)
+ {
+ (**di).m_rulez = NULL;
+ (**di).m_syntax = NULL;
+ (**di).m_string = NULL;
+ (**di).m_regbytes = NULL;
+ (**di).m_id = next_valid_grammar_id ();
+ (**di).m_next = NULL;
+ }
+}
+
+static void dict_destroy (dict **di)
+{
+ if (*di)
+ {
+ rule_destroy (&(**di).m_rulez);
+ map_byte_destroy (&(**di).m_regbytes);
+ mem_free ((void **) di);
+ }
+}
+
+static void dict_append (dict **di, dict **nd)
+{
+ while (*di)
+ di = &(**di).m_next;
+ *di = *nd;
+}
+
+static void dict_find (dict **di, grammar key, dict **data)
+{
+ while (*di)
+ {
+ if ((**di).m_id == key)
+ {
+ *data = *di;
+ return;
+ }
+
+ di = &(**di).m_next;
+ }
+
+ *data = NULL;
+}
+
+static dict *g_dicts = NULL;
+
+/*
+ byte array typedef
+
+ XXX this class is going to be replaced by a faster one, soon
+*/
+typedef struct barray_
+{
+ byte *data;
+ unsigned int len;
+} barray;
+
+static void barray_create (barray **ba)
+{
+ *ba = mem_alloc (sizeof (barray));
+ if (*ba)
+ {
+ (**ba).data = NULL;
+ (**ba).len = 0;
+ }
+}
+
+static void barray_destroy (barray **ba)
+{
+ if (*ba)
+ {
+ mem_free ((void **) &(**ba).data);
+ mem_free ((void **) ba);
+ }
+}
+
+/*
+ reallocates byte array to requested size,
+ returns 0 on success,
+ returns 1 otherwise
+*/
+static int barray_resize (barray **ba, unsigned int nlen)
+{
+ byte *new_pointer;
+
+ if (nlen == 0)
+ {
+ mem_free ((void **) &(**ba).data);
+ (**ba).data = NULL;
+ (**ba).len = 0;
+
+ return 0;
+ }
+ else
+ {
+ new_pointer = mem_realloc ((**ba).data, (**ba).len * sizeof (byte), nlen * sizeof (byte));
+ if (new_pointer)
+ {
+ (**ba).data = new_pointer;
+ (**ba).len = nlen;
+
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+/*
+ adds byte array pointed by *nb to the end of array pointed by *ba,
+ returns 0 on success,
+ returns 1 otherwise
+*/
+static int barray_append (barray **ba, barray **nb)
+{
+ const unsigned int len = (**ba).len;
+
+ if (barray_resize (ba, (**ba).len + (**nb).len))
+ return 1;
+
+ mem_copy ((**ba).data + len, (**nb).data, (**nb).len);
+
+ return 0;
+}
+
+/*
+ adds emit chain pointed by em to the end of array pointed by *ba,
+ returns 0 on success,
+ returns 1 otherwise
+*/
+static int barray_push (barray **ba, emit *em, byte c, unsigned int pos, regbyte_ctx **rbc)
+{
+ emit *temp = em;
+ unsigned int count = 0;
+
+ while (temp)
+ {
+ if (temp->m_emit_dest == ed_output)
+ if (temp->m_emit_type == et_position)
+ count += 4; /* position is a 32-bit unsigned integer */
+ else
+ count++;
+
+ temp = temp->m_next;
+ }
+
+ if (barray_resize (ba, (**ba).len + count))
+ return 1;
+
+ while (em)
+ {
+ if (em->m_emit_dest == ed_output)
+ {
+ if (em->m_emit_type == et_byte)
+ (**ba).data[(**ba).len - count--] = em->m_byte;
+ else if (em->m_emit_type == et_stream)
+ (**ba).data[(**ba).len - count--] = c;
+ else // em->type == et_position
+ (**ba).data[(**ba).len - count--] = (byte) pos,
+ (**ba).data[(**ba).len - count--] = (byte) (pos >> 8),
+ (**ba).data[(**ba).len - count--] = (byte) (pos >> 16),
+ (**ba).data[(**ba).len - count--] = (byte) (pos >> 24);
+ }
+ else
+ {
+ regbyte_ctx *new_rbc;
+ regbyte_ctx_create (&new_rbc);
+ if (new_rbc == NULL)
+ return 1;
+
+ new_rbc->m_prev = *rbc;
+ new_rbc->m_regbyte = em->m_regbyte;
+ *rbc = new_rbc;
+
+ if (em->m_emit_type == et_byte)
+ new_rbc->m_current_value = em->m_byte;
+ else if (em->m_emit_type == et_stream)
+ new_rbc->m_current_value = c;
+ }
+
+ em = em->m_next;
+ }
+
+ return 0;
+}
+
+/*
+ string to string map typedef
+*/
+typedef struct map_str_
+{
+ byte *key;
+ byte *data;
+ struct map_str_ *next;
+} map_str;
+
+static void map_str_create (map_str **ma)
+{
+ *ma = mem_alloc (sizeof (map_str));
+ if (*ma)
+ {
+ (**ma).key = NULL;
+ (**ma).data = NULL;
+ (**ma).next = NULL;
+ }
+}
+
+static void map_str_destroy (map_str **ma)
+{
+ if (*ma)
+ {
+ map_str_destroy (&(**ma).next);
+ mem_free ((void **) &(**ma).key);
+ mem_free ((void **) &(**ma).data);
+ mem_free ((void **) ma);
+ }
+}
+
+static void map_str_append (map_str **ma, map_str **nm)
+{
+ while (*ma)
+ ma = &(**ma).next;
+ *ma = *nm;
+}
+
+/*
+ searches the map for specified key,
+ if the key is matched, *data is filled with data associated with the key,
+ returns 0 if the key is matched,
+ returns 1 otherwise
+*/
+static int map_str_find (map_str **ma, const byte *key, byte **data)
+{
+ while (*ma)
+ {
+ if (str_equal ((**ma).key, key))
+ {
+ *data = str_duplicate ((**ma).data);
+ if (*data == NULL)
+ return 1;
+
+ return 0;
+ }
+
+ ma = &(**ma).next;
+ }
+
+ set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
+ return 1;
+}
+
+/*
+ string to rule map typedef
+*/
+typedef struct map_rule_
+{
+ byte *key;
+ rule *data;
+ struct map_rule_ *next;
+} map_rule;
+
+static void map_rule_create (map_rule **ma)
+{
+ *ma = mem_alloc (sizeof (map_rule));
+ if (*ma)
+ {
+ (**ma).key = NULL;
+ (**ma).data = NULL;
+ (**ma).next = NULL;
+ }
+}
+
+static void map_rule_destroy (map_rule **ma)
+{
+ if (*ma)
+ {
+ map_rule_destroy (&(**ma).next);
+ mem_free ((void **) &(**ma).key);
+ mem_free ((void **) ma);
+ }
+}
+
+static void map_rule_append (map_rule **ma, map_rule **nm)
+{
+ while (*ma)
+ ma = &(**ma).next;
+ *ma = *nm;
+}
+
+/*
+ searches the map for specified key,
+ if the key is matched, *data is filled with data associated with the key,
+ returns 0 if the is matched,
+ returns 1 otherwise
+*/
+static int map_rule_find (map_rule **ma, const byte *key, rule **data)
+{
+ while (*ma)
+ {
+ if (str_equal ((**ma).key, key))
+ {
+ *data = (**ma).data;
+
+ return 0;
+ }
+
+ ma = &(**ma).next;
+ }
+
+ set_last_error (UNRESOLVED_REFERENCE, str_duplicate (key), -1);
+ return 1;
+}
+
+/*
+ returns 1 if given character is a white space,
+ returns 0 otherwise
+*/
+static int is_space (byte c)
+{
+ return c == ' ' || c == '\t' || c == '\n' || c == '\r';
+}
+
+/*
+ advances text pointer by 1 if character pointed by *text is a space,
+ returns 1 if a space has been eaten,
+ returns 0 otherwise
+*/
+static int eat_space (const byte **text)
+{
+ if (is_space (**text))
+ {
+ (*text)++;
+
+ return 1;
+ }
+
+ return 0;
+}
+
+/*
+ returns 1 if text points to C-style comment start string "/*",
+ returns 0 otherwise
+*/
+static int is_comment_start (const byte *text)
+{
+ return text[0] == '/' && text[1] == '*';
+}
+
+/*
+ advances text pointer to first character after C-style comment block - if any,
+ returns 1 if C-style comment block has been encountered and eaten,
+ returns 0 otherwise
+*/
+static int eat_comment (const byte **text)
+{
+ if (is_comment_start (*text))
+ {
+ /* *text points to comment block - skip two characters to enter comment body */
+ *text += 2;
+ /* skip any character except consecutive '*' and '/' */
+ while (!((*text)[0] == '*' && (*text)[1] == '/'))
+ (*text)++;
+ /* skip those two terminating characters */
+ *text += 2;
+
+ return 1;
+ }
+
+ return 0;
+}
+
+/*
+ advances text pointer to first character that is neither space nor C-style comment block
+*/
+static void eat_spaces (const byte **text)
+{
+ while (eat_space (text) || eat_comment (text))
+ ;
+}
+
+/*
+ resizes string pointed by *ptr to successfully add character c to the end of the string,
+ returns 0 on success,
+ returns 1 otherwise
+*/
+static int string_grow (byte **ptr, unsigned int *len, byte c)
+{
+ /* reallocate the string in 16-byte increments */
+ if ((*len & 0x0F) == 0x0F || *ptr == NULL)
+ {
+ byte *tmp = mem_realloc (*ptr, ((*len + 1) & ~0x0F) * sizeof (byte),
+ ((*len + 1 + 0x10) & ~0x0F) * sizeof (byte));
+ if (tmp == NULL)
+ return 1;
+
+ *ptr = tmp;
+ }
+
+ if (c)
+ {
+ /* append given character */
+ (*ptr)[*len] = c;
+ (*len)++;
+ }
+ (*ptr)[*len] = '\0';
+
+ return 0;
+}
+
+/*
+ returns 1 if given character is a valid identifier character a-z, A-Z, 0-9 or _
+ returns 0 otherwise
+*/
+static int is_identifier (byte c)
+{
+ return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_';
+}
+
+/*
+ copies characters from *text to *id until non-identifier character is encountered,
+ assumes that *id points to NULL object - caller is responsible for later freeing the string,
+ text pointer is advanced to point past the copied identifier,
+ returns 0 if identifier was successfully copied,
+ returns 1 otherwise
+*/
+static int get_identifier (const byte **text, byte **id)
+{
+ const byte *t = *text;
+ byte *p = NULL;
+ unsigned int len = 0;
+
+ if (string_grow (&p, &len, '\0'))
+ return 1;
+
+ /* loop while next character in buffer is valid for identifiers */
+ while (is_identifier (*t))
+ {
+ if (string_grow (&p, &len, *t++))
+ {
+ mem_free ((void **) &p);
+ return 1;
+ }
+ }
+
+ *text = t;
+ *id = p;
+
+ return 0;
+}
+
+/*
+ returns 1 if given character is HEX digit 0-9, A-F or a-f,
+ returns 0 otherwise
+*/
+static int is_hex (byte c)
+{
+ return (c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f');
+}
+
+/*
+ returns value of passed character as if it was HEX digit
+*/
+static unsigned int hex2dec (byte c)
+{
+ if (c >= '0' && c <= '9')
+ return c - '0';
+ if (c >= 'A' && c <= 'F')
+ return c - 'A' + 10;
+ return c - 'a' + 10;
+}
+
+/*
+ converts sequence of HEX digits pointed by *text until non-HEX digit is encountered,
+ advances text pointer past the converted sequence,
+ returns the converted value
+*/
+static unsigned int hex_convert (const byte **text)
+{
+ unsigned int value = 0;
+
+ while (is_hex (**text))
+ {
+ value = value * 0x10 + hex2dec (**text);
+ (*text)++;
+ }
+
+ return value;
+}
+
+/*
+ returns 1 if given character is OCT digit 0-7,
+ returns 0 otherwise
+*/
+static int is_oct (byte c)
+{
+ return c >= '0' && c <= '7';
+}
+
+/*
+ returns value of passed character as if it was OCT digit
+*/
+static int oct2dec (byte c)
+{
+ return c - '0';
+}
+
+static byte get_escape_sequence (const byte **text)
+{
+ int value = 0;
+
+ /* skip '\' character */
+ (*text)++;
+
+ switch (*(*text)++)
+ {
+ case '\'':
+ return '\'';
+ case '"':
+ return '\"';
+ case '?':
+ return '\?';
+ case '\\':
+ return '\\';
+ case 'a':
+ return '\a';
+ case 'b':
+ return '\b';
+ case 'f':
+ return '\f';
+ case 'n':
+ return '\n';
+ case 'r':
+ return '\r';
+ case 't':
+ return '\t';
+ case 'v':
+ return '\v';
+ case 'x':
+ return (byte) hex_convert (text);
+ }
+
+ (*text)--;
+ if (is_oct (**text))
+ {
+ value = oct2dec (*(*text)++);
+ if (is_oct (**text))
+ {
+ value = value * 010 + oct2dec (*(*text)++);
+ if (is_oct (**text))
+ value = value * 010 + oct2dec (*(*text)++);
+ }
+ }
+
+ return (byte) value;
+}
+
+/*
+ copies characters from *text to *str until " or ' character is encountered,
+ assumes that *str points to NULL object - caller is responsible for later freeing the string,
+ assumes that *text points to " or ' character that starts the string,
+ text pointer is advanced to point past the " or ' character,
+ returns 0 if string was successfully copied,
+ returns 1 otherwise
+*/
+static int get_string (const byte **text, byte **str)
+{
+ const byte *t = *text;
+ byte *p = NULL;
+ unsigned int len = 0;
+ byte term_char;
+
+ if (string_grow (&p, &len, '\0'))
+ return 1;
+
+ /* read " or ' character that starts the string */
+ term_char = *t++;
+ /* while next character is not the terminating character */
+ while (*t && *t != term_char)
+ {
+ byte c;
+
+ if (*t == '\\')
+ c = get_escape_sequence (&t);
+ else
+ c = *t++;
+
+ if (string_grow (&p, &len, c))
+ {
+ mem_free ((void **) &p);
+ return 1;
+ }
+ }
+ /* skip " or ' character that ends the string */
+ t++;
+
+ *text = t;
+ *str = p;
+ return 0;
+}
+
+/*
+ gets emit code, the syntax is: ".emtcode" " " <symbol> " " ("0x" | "0X") <hex_value>
+ assumes that *text already points to <symbol>,
+ returns 0 if emit code is successfully read,
+ returns 1 otherwise
+*/
+static int get_emtcode (const byte **text, map_byte **ma)
+{
+ const byte *t = *text;
+ map_byte *m = NULL;
+
+ map_byte_create (&m);
+ if (m == NULL)
+ return 1;
+
+ if (get_identifier (&t, &m->key))
+ {
+ map_byte_destroy (&m);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ if (*t == '\'')
+ {
+ byte *c;
+
+ if (get_string (&t, &c))
+ {
+ map_byte_destroy (&m);
+ return 1;
+ }
+
+ m->data = (byte) c[0];
+ mem_free ((void **) &c);
+ }
+ else
+ {
+ /* skip HEX "0x" or "0X" prefix */
+ t += 2;
+ m->data = (byte) hex_convert (&t);
+ }
+
+ eat_spaces (&t);
+
+ *text = t;
+ *ma = m;
+ return 0;
+}
+
+/*
+ gets regbyte declaration, the syntax is: ".regbyte" " " <symbol> " " ("0x" | "0X") <hex_value>
+ assumes that *text already points to <symbol>,
+ returns 0 if regbyte is successfully read,
+ returns 1 otherwise
+*/
+static int get_regbyte (const byte **text, map_byte **ma)
+{
+ return get_emtcode (text, ma);
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise
+*/
+static int get_errtext (const byte **text, map_str **ma)
+{
+ const byte *t = *text;
+ map_str *m = NULL;
+
+ map_str_create (&m);
+ if (m == NULL)
+ return 1;
+
+ if (get_identifier (&t, &m->key))
+ {
+ map_str_destroy (&m);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ if (get_string (&t, &m->data))
+ {
+ map_str_destroy (&m);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ *text = t;
+ *ma = m;
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int get_error (const byte **text, error **er, map_str *maps)
+{
+ const byte *t = *text;
+ byte *temp = NULL;
+
+ if (*t != '.')
+ return 0;
+
+ t++;
+ if (get_identifier (&t, &temp))
+ return 1;
+ eat_spaces (&t);
+
+ if (!str_equal ((byte *) "error", temp))
+ {
+ mem_free ((void **) &temp);
+ return 0;
+ }
+
+ mem_free ((void **) &temp);
+
+ error_create (er);
+ if (*er == NULL)
+ return 1;
+
+ if (*t == '\"')
+ {
+ if (get_string (&t, &(**er).m_text))
+ {
+ error_destroy (er);
+ return 1;
+ }
+ eat_spaces (&t);
+ }
+ else
+ {
+ if (get_identifier (&t, &temp))
+ {
+ error_destroy (er);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ if (map_str_find (&maps, temp, &(**er).m_text))
+ {
+ mem_free ((void **) &temp);
+ error_destroy (er);
+ return 1;
+ }
+
+ mem_free ((void **) &temp);
+ }
+
+ /* try to extract "token" from "...$token$..." */
+ {
+ byte *processed = NULL;
+ unsigned int len = 0, i = 0;
+
+ if (string_grow (&processed, &len, '\0'))
+ {
+ error_destroy (er);
+ return 1;
+ }
+
+ while (i < str_length ((**er).m_text))
+ {
+ /* check if the dollar sign is repeated - if so skip it */
+ if ((**er).m_text[i] == '$' && (**er).m_text[i + 1] == '$')
+ {
+ if (string_grow (&processed, &len, '$'))
+ {
+ mem_free ((void **) &processed);
+ error_destroy (er);
+ return 1;
+ }
+
+ i += 2;
+ }
+ else if ((**er).m_text[i] != '$')
+ {
+ if (string_grow (&processed, &len, (**er).m_text[i]))
+ {
+ mem_free ((void **) &processed);
+ error_destroy (er);
+ return 1;
+ }
+
+ i++;
+ }
+ else
+ {
+ if (string_grow (&processed, &len, '$'))
+ {
+ mem_free ((void **) &processed);
+ error_destroy (er);
+ return 1;
+ }
+
+ {
+ /* length of token being extracted */
+ unsigned int tlen = 0;
+
+ if (string_grow (&(**er).m_token_name, &tlen, '\0'))
+ {
+ mem_free ((void **) &processed);
+ error_destroy (er);
+ return 1;
+ }
+
+ /* skip the dollar sign */
+ i++;
+
+ while ((**er).m_text[i] != '$')
+ {
+ if (string_grow (&(**er).m_token_name, &tlen, (**er).m_text[i]))
+ {
+ mem_free ((void **) &processed);
+ error_destroy (er);
+ return 1;
+ }
+
+ i++;
+ }
+
+ /* skip the dollar sign */
+ i++;
+ }
+ }
+ }
+
+ mem_free ((void **) &(**er).m_text);
+ (**er).m_text = processed;
+ }
+
+ *text = t;
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int get_emits (const byte **text, emit **em, map_byte *mapb)
+{
+ const byte *t = *text;
+ byte *temp = NULL;
+ emit *e = NULL;
+ emit_dest dest;
+
+ if (*t != '.')
+ return 0;
+
+ t++;
+ if (get_identifier (&t, &temp))
+ return 1;
+ eat_spaces (&t);
+
+ /* .emit */
+ if (str_equal ((byte *) "emit", temp))
+ dest = ed_output;
+ /* .load */
+ else if (str_equal ((byte *) "load", temp))
+ dest = ed_regbyte;
+ else
+ {
+ mem_free ((void **) &temp);
+ return 0;
+ }
+
+ mem_free ((void **) &temp);
+
+ emit_create (&e);
+ if (e == NULL)
+ return 1;
+
+ e->m_emit_dest = dest;
+
+ if (dest == ed_regbyte)
+ {
+ if (get_identifier (&t, &e->m_regname))
+ {
+ emit_destroy (&e);
+ return 1;
+ }
+ eat_spaces (&t);
+ }
+
+ /* 0xNN */
+ if (*t == '0')
+ {
+ t += 2;
+ e->m_byte = (byte) hex_convert (&t);
+
+ e->m_emit_type = et_byte;
+ }
+ /* * */
+ else if (*t == '*')
+ {
+ t++;
+
+ e->m_emit_type = et_stream;
+ }
+ /* $ */
+ else if (*t == '$')
+ {
+ t++;
+
+ e->m_emit_type = et_position;
+ }
+ /* 'c' */
+ else if (*t == '\'')
+ {
+ if (get_string (&t, &temp))
+ {
+ emit_destroy (&e);
+ return 1;
+ }
+ e->m_byte = (byte) temp[0];
+
+ mem_free ((void **) &temp);
+
+ e->m_emit_type = et_byte;
+ }
+ else
+ {
+ if (get_identifier (&t, &temp))
+ {
+ emit_destroy (&e);
+ return 1;
+ }
+
+ if (map_byte_find (&mapb, temp, &e->m_byte))
+ {
+ mem_free ((void **) &temp);
+ emit_destroy (&e);
+ return 1;
+ }
+
+ mem_free ((void **) &temp);
+
+ e->m_emit_type = et_byte;
+ }
+
+ eat_spaces (&t);
+
+ if (get_emits (&t, &e->m_next, mapb))
+ {
+ emit_destroy (&e);
+ return 1;
+ }
+
+ *text = t;
+ *em = e;
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int get_spec (const byte **text, spec **sp, map_str *maps, map_byte *mapb)
+{
+ const byte *t = *text;
+ spec *s = NULL;
+
+ spec_create (&s);
+ if (s == NULL)
+ return 1;
+
+ /* first - read optional .if statement */
+ if (*t == '.')
+ {
+ const byte *u = t;
+ byte *keyword = NULL;
+
+ /* skip the dot */
+ u++;
+
+ if (get_identifier (&u, &keyword))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+
+ /* .if */
+ if (str_equal ((byte *) "if", keyword))
+ {
+ cond_create (&s->m_cond);
+ if (s->m_cond == NULL)
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+
+ /* skip the left paren */
+ eat_spaces (&u);
+ u++;
+
+ /* get the left operand */
+ eat_spaces (&u);
+ if (get_identifier (&u, &s->m_cond->m_operands[0].m_regname))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+ s->m_cond->m_operands[0].m_type = cot_regbyte;
+
+ /* get the operator (!= or ==) */
+ eat_spaces (&u);
+ if (*u == '!')
+ s->m_cond->m_type = ct_not_equal;
+ else
+ s->m_cond->m_type = ct_equal;
+ u += 2;
+
+ /* skip the 0x prefix */
+ eat_spaces (&u);
+ u += 2;
+
+ /* get the right operand */
+ s->m_cond->m_operands[1].m_byte = hex_convert (&u);
+ s->m_cond->m_operands[1].m_type = cot_byte;
+
+ /* skip the right paren */
+ eat_spaces (&u);
+ u++;
+
+ eat_spaces (&u);
+
+ t = u;
+ }
+
+ mem_free ((void **) &keyword);
+ }
+
+ if (*t == '\'')
+ {
+ byte *temp = NULL;
+
+ if (get_string (&t, &temp))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ if (*t == '-')
+ {
+ byte *temp2 = NULL;
+
+ /* skip the '-' character */
+ t++;
+ eat_spaces (&t);
+
+ if (get_string (&t, &temp2))
+ {
+ mem_free ((void **) &temp);
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ s->m_spec_type = st_byte_range;
+ s->m_byte[0] = *temp;
+ s->m_byte[1] = *temp2;
+
+ mem_free ((void **) &temp2);
+ }
+ else
+ {
+ s->m_spec_type = st_byte;
+ *s->m_byte = *temp;
+ }
+
+ mem_free ((void **) &temp);
+ }
+ else if (*t == '"')
+ {
+ if (get_string (&t, &s->m_string))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ s->m_spec_type = st_string;
+ }
+ else if (*t == '.')
+ {
+ byte *keyword = NULL;
+
+ /* skip the dot */
+ t++;
+
+ if (get_identifier (&t, &keyword))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ /* .true */
+ if (str_equal ((byte *) "true", keyword))
+ {
+ s->m_spec_type = st_true;
+ }
+ /* .false */
+ else if (str_equal ((byte *) "false", keyword))
+ {
+ s->m_spec_type = st_false;
+ }
+ /* .debug */
+ else if (str_equal ((byte *) "debug", keyword))
+ {
+ s->m_spec_type = st_debug;
+ }
+ /* .loop */
+ else if (str_equal ((byte *) "loop", keyword))
+ {
+ if (get_identifier (&t, &s->m_string))
+ {
+ mem_free ((void **) &keyword);
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ s->m_spec_type = st_identifier_loop;
+ }
+
+ mem_free ((void **) &keyword);
+ }
+ else
+ {
+ if (get_identifier (&t, &s->m_string))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ s->m_spec_type = st_identifier;
+ }
+
+ if (get_error (&t, &s->m_errtext, maps))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+
+ if (get_emits (&t, &s->m_emits, mapb))
+ {
+ spec_destroy (&s);
+ return 1;
+ }
+
+ *text = t;
+ *sp = s;
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int get_rule (const byte **text, rule **ru, map_str *maps, map_byte *mapb)
+{
+ const byte *t = *text;
+ rule *r = NULL;
+
+ rule_create (&r);
+ if (r == NULL)
+ return 1;
+
+ if (get_spec (&t, &r->m_specs, maps, mapb))
+ {
+ rule_destroy (&r);
+ return 1;
+ }
+
+ while (*t != ';')
+ {
+ byte *op = NULL;
+ spec *sp = NULL;
+
+ /* skip the dot that precedes "and" or "or" */
+ t++;
+
+ /* read "and" or "or" keyword */
+ if (get_identifier (&t, &op))
+ {
+ rule_destroy (&r);
+ return 1;
+ }
+ eat_spaces (&t);
+
+ if (r->m_oper == op_none)
+ {
+ /* .and */
+ if (str_equal ((byte *) "and", op))
+ r->m_oper = op_and;
+ /* .or */
+ else
+ r->m_oper = op_or;
+ }
+
+ mem_free ((void **) &op);
+
+ if (get_spec (&t, &sp, maps, mapb))
+ {
+ rule_destroy (&r);
+ return 1;
+ }
+
+ spec_append (&r->m_specs, &sp);
+ }
+
+ /* skip the semicolon */
+ t++;
+ eat_spaces (&t);
+
+ *text = t;
+ *ru = r;
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int update_dependency (map_rule *mapr, byte *symbol, rule **ru)
+{
+ if (map_rule_find (&mapr, symbol, ru))
+ return 1;
+
+/* (**ru).m_referenced = 1; */
+
+ return 0;
+}
+
+/*
+ returns 0 on success,
+ returns 1 otherwise,
+*/
+static int update_dependencies (dict *di, map_rule *mapr, byte **syntax_symbol,
+ byte **string_symbol, map_byte *regbytes)
+{
+ rule *rulez = di->m_rulez;
+
+ /* update dependecies for the root and lexer symbols */
+ if (update_dependency (mapr, *syntax_symbol, &di->m_syntax) ||
+ (*string_symbol != NULL && update_dependency (mapr, *string_symbol, &di->m_string)))
+ return 1;
+
+ mem_free ((void **) syntax_symbol);
+ mem_free ((void **) string_symbol);
+
+ /* update dependecies for the rest of the rules */
+ while (rulez)
+ {
+ spec *sp = rulez->m_specs;
+
+ /* iterate through all the specifiers */
+ while (sp)
+ {
+ /* update dependency for identifier */
+ if (sp->m_spec_type == st_identifier || sp->m_spec_type == st_identifier_loop)
+ {
+ if (update_dependency (mapr, sp->m_string, &sp->m_rule))
+ return 1;
+
+ mem_free ((void **) &sp->m_string);
+ }
+
+ /* some errtexts reference to a rule */
+ if (sp->m_errtext && sp->m_errtext->m_token_name)
+ {
+ if (update_dependency (mapr, sp->m_errtext->m_token_name, &sp->m_errtext->m_token))
+ return 1;
+
+ mem_free ((void **) &sp->m_errtext->m_token_name);
+ }
+
+ /* update dependency for condition */
+ if (sp->m_cond)
+ {
+ int i;
+ for (i = 0; i < 2; i++)
+ if (sp->m_cond->m_operands[i].m_type == cot_regbyte)
+ {
+ sp->m_cond->m_operands[i].m_regbyte = map_byte_locate (&regbytes,
+ sp->m_cond->m_operands[i].m_regname);
+
+ if (sp->m_cond->m_operands[i].m_regbyte == NULL)
+ return 1;
+
+ mem_free ((void **) &sp->m_cond->m_operands[i].m_regname);
+ }
+ }
+
+ /* update dependency for all .load instructions */
+ if (sp->m_emits)
+ {
+ emit *em = sp->m_emits;
+ while (em != NULL)
+ {
+ if (em->m_emit_dest == ed_regbyte)
+ {
+ em->m_regbyte = map_byte_locate (&regbytes, em->m_regname);
+
+ if (em->m_regbyte == NULL)
+ return 1;
+
+ mem_free ((void **) &em->m_regname);
+ }
+
+ em = em->m_next;
+ }
+ }
+
+ sp = sp->m_next;
+ }
+
+ rulez = rulez->m_next;
+ }
+
+/* check for unreferenced symbols */
+/* de = di->m_defntns;
+ while (de)
+ {
+ if (!de->m_referenced)
+ {
+ map_def *ma = mapd;
+ while (ma)
+ {
+ if (ma->data == de)
+ {
+ assert (0);
+ break;
+ }
+ ma = ma->next;
+ }
+ }
+ de = de->m_next;
+ }
+*/
+ return 0;
+}
+
+static int satisfies_condition (cond *co, regbyte_ctx *ctx)
+{
+ byte values[2];
+ int i;
+
+ if (co == NULL)
+ return 1;
+
+ for (i = 0; i < 2; i++)
+ switch (co->m_operands[i].m_type)
+ {
+ case cot_byte:
+ values[i] = co->m_operands[i].m_byte;
+ break;
+ case cot_regbyte:
+ values[i] = regbyte_ctx_extract (&ctx, co->m_operands[i].m_regbyte);
+ break;
+ }
+
+ switch (co->m_type)
+ {
+ case ct_equal:
+ return values[0] == values[1];
+ case ct_not_equal:
+ return values[0] != values[1];
+ }
+
+ return 0;
+}
+
+static void free_regbyte_ctx_stack (regbyte_ctx *top, regbyte_ctx *limit)
+{
+ while (top != limit)
+ {
+ regbyte_ctx *rbc = top->m_prev;
+ regbyte_ctx_destroy (&top);
+ top = rbc;
+ }
+}
+
+typedef enum match_result_
+{
+ mr_not_matched, /* the examined string does not match */
+ mr_matched, /* the examined string matches */
+ mr_error_raised, /* mr_not_matched + error has been raised */
+ mr_dont_emit, /* used by identifier loops only */
+ mr_internal_error /* an internal error has occured such as out of memory */
+} match_result;
+
+/*
+ This function does the main job. It parses the text and generates output data.
+
+ XXX optimize it - the barray seems to be the bottleneck
+*/
+static match_result match (dict *di, const byte *text, unsigned int *index, rule *ru, barray **ba,
+ int filtering_string, regbyte_ctx **rbc)
+{
+ unsigned int ind = *index;
+ match_result status = mr_not_matched;
+ spec *sp = ru->m_specs;
+ regbyte_ctx *ctx = *rbc;
+
+ /* for every specifier in the rule */
+ while (sp)
+ {
+ unsigned int i, len, save_ind = ind;
+ barray *array = NULL;
+
+ if (satisfies_condition (sp->m_cond, ctx))
+ {
+ switch (sp->m_spec_type)
+ {
+ case st_identifier:
+ barray_create (&array);
+ if (array == NULL)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ return mr_internal_error;
+ }
+
+ status = match (di, text, &ind, sp->m_rule, &array, filtering_string, &ctx);
+ if (status == mr_internal_error)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+ return mr_internal_error;
+ }
+ break;
+ case st_string:
+ len = str_length (sp->m_string);
+
+ /* prefilter the stream */
+ if (!filtering_string && di->m_string)
+ {
+ barray *ba;
+ unsigned int filter_index = 0;
+ match_result result;
+ regbyte_ctx *null_ctx = NULL;
+
+ barray_create (&ba);
+ if (ba == NULL)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ return mr_internal_error;
+ }
+
+ result = match (di, text + ind, &filter_index, di->m_string, &ba, 1, &null_ctx);
+
+ if (result == mr_internal_error)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&ba);
+ return mr_internal_error;
+ }
+
+ if (result != mr_matched)
+ {
+ barray_destroy (&ba);
+ status = mr_not_matched;
+ break;
+ }
+
+ barray_destroy (&ba);
+
+ if (filter_index != len || !str_equal_n (sp->m_string, text + ind, len))
+ {
+ status = mr_not_matched;
+ break;
+ }
+
+ status = mr_matched;
+ ind += len;
+ }
+ else
+ {
+ status = mr_matched;
+ for (i = 0; status == mr_matched && i < len; i++)
+ if (text[ind + i] != sp->m_string[i])
+ status = mr_not_matched;
+ if (status == mr_matched)
+ ind += len;
+ }
+ break;
+ case st_byte:
+ status = text[ind] == *sp->m_byte ? mr_matched : mr_not_matched;
+ if (status == mr_matched)
+ ind++;
+ break;
+ case st_byte_range:
+ status = (text[ind] >= sp->m_byte[0] && text[ind] <= sp->m_byte[1]) ?
+ mr_matched : mr_not_matched;
+ if (status == mr_matched)
+ ind++;
+ break;
+ case st_true:
+ status = mr_matched;
+ break;
+ case st_false:
+ status = mr_not_matched;
+ break;
+ case st_debug:
+ status = ru->m_oper == op_and ? mr_matched : mr_not_matched;
+ break;
+ case st_identifier_loop:
+ barray_create (&array);
+ if (array == NULL)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ return mr_internal_error;
+ }
+
+ status = mr_dont_emit;
+ for (;;)
+ {
+ match_result result;
+
+ save_ind = ind;
+ result = match (di, text, &ind, sp->m_rule, &array, filtering_string, &ctx);
+
+ if (result == mr_error_raised)
+ {
+ status = result;
+ break;
+ }
+ else if (result == mr_matched)
+ {
+ if (barray_push (ba, sp->m_emits, text[ind - 1], save_ind, &ctx) ||
+ barray_append (ba, &array))
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+ return mr_internal_error;
+ }
+ barray_destroy (&array);
+ barray_create (&array);
+ if (array == NULL)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ return mr_internal_error;
+ }
+ }
+ else if (result == mr_internal_error)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+ return mr_internal_error;
+ }
+ else
+ break;
+ }
+ break;
+ }
+ }
+ else
+ {
+ status = mr_not_matched;
+ }
+
+ if (status == mr_error_raised)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+
+ return mr_error_raised;
+ }
+
+ if (ru->m_oper == op_and && status != mr_matched && status != mr_dont_emit)
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+
+ if (sp->m_errtext)
+ {
+ set_last_error (sp->m_errtext->m_text, error_get_token (sp->m_errtext, di, text,
+ ind), ind);
+
+ return mr_error_raised;
+ }
+
+ return mr_not_matched;
+ }
+
+ if (status == mr_matched)
+ {
+ if (sp->m_emits)
+ if (barray_push (ba, sp->m_emits, text[ind - 1], save_ind, &ctx))
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+ return mr_internal_error;
+ }
+
+ if (array)
+ if (barray_append (ba, &array))
+ {
+ free_regbyte_ctx_stack (ctx, *rbc);
+ barray_destroy (&array);
+ return mr_internal_error;
+ }
+ }
+
+ barray_destroy (&array);
+
+ /* if the rule operator is a logical or, we pick up the first matching specifier */
+ if (ru->m_oper == op_or && (status == mr_matched || status == mr_dont_emit))
+ {
+ *index = ind;
+ *rbc = ctx;
+ return mr_matched;
+ }
+
+ sp = sp->m_next;
+ }
+
+ /* everything went fine - all specifiers match up */
+ if (ru->m_oper == op_and && (status == mr_matched || status == mr_dont_emit))
+ {
+ *index = ind;
+ *rbc = ctx;
+ return mr_matched;
+ }
+
+ free_regbyte_ctx_stack (ctx, *rbc);
+ return mr_not_matched;
+}
+
+static byte *error_get_token (error *er, dict *di, const byte *text, unsigned int ind)
+{
+ byte *str = NULL;
+
+ if (er->m_token)
+ {
+ barray *ba;
+ unsigned int filter_index = 0;
+ regbyte_ctx *ctx = NULL;
+
+ barray_create (&ba);
+ if (ba != NULL)
+ {
+ if (match (di, text + ind, &filter_index, er->m_token, &ba, 0, &ctx) == mr_matched &&
+ filter_index)
+ {
+ str = mem_alloc (filter_index + 1);
+ if (str != NULL)
+ {
+ str_copy_n (str, text + ind, filter_index);
+ str[filter_index] = '\0';
+ }
+ }
+ barray_destroy (&ba);
+ }
+ }
+
+ return str;
+}
+
+typedef struct grammar_load_state_
+{
+ dict *di;
+ byte *syntax_symbol;
+ byte *string_symbol;
+ map_str *maps;
+ map_byte *mapb;
+ map_rule *mapr;
+} grammar_load_state;
+
+static void grammar_load_state_create (grammar_load_state **gr)
+{
+ *gr = mem_alloc (sizeof (grammar_load_state));
+ if (*gr)
+ {
+ (**gr).di = NULL;
+ (**gr).syntax_symbol = NULL;
+ (**gr).string_symbol = NULL;
+ (**gr).maps = NULL;
+ (**gr).mapb = NULL;
+ (**gr).mapr = NULL;
+ }
+}
+
+static void grammar_load_state_destroy (grammar_load_state **gr)
+{
+ if (*gr)
+ {
+ dict_destroy (&(**gr).di);
+ mem_free ((void **) &(**gr).syntax_symbol);
+ mem_free ((void **) &(**gr).string_symbol);
+ map_str_destroy (&(**gr).maps);
+ map_byte_destroy (&(**gr).mapb);
+ map_rule_destroy (&(**gr).mapr);
+ mem_free ((void **) gr);
+ }
+}
+
+/*
+ the API
+*/
+
+grammar grammar_load_from_text (const byte *text)
+{
+ grammar_load_state *g = NULL;
+ grammar id = 0;
+
+ clear_last_error ();
+
+ grammar_load_state_create (&g);
+ if (g == NULL)
+ return 0;
+
+ dict_create (&g->di);
+ if (g->di == NULL)
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ eat_spaces (&text);
+
+ /* skip ".syntax" keyword */
+ text += 7;
+ eat_spaces (&text);
+
+ /* retrieve root symbol */
+ if (get_identifier (&text, &g->syntax_symbol))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+ eat_spaces (&text);
+
+ /* skip semicolon */
+ text++;
+ eat_spaces (&text);
+
+ while (*text)
+ {
+ byte *symbol = NULL;
+ int is_dot = *text == '.';
+
+ if (is_dot)
+ text++;
+
+ if (get_identifier (&text, &symbol))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+ eat_spaces (&text);
+
+ /* .emtcode */
+ if (is_dot && str_equal (symbol, (byte *) "emtcode"))
+ {
+ map_byte *ma = NULL;
+
+ mem_free ((void **) &symbol);
+
+ if (get_emtcode (&text, &ma))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ map_byte_append (&g->mapb, &ma);
+ }
+ /* .regbyte */
+ else if (is_dot && str_equal (symbol, (byte *) "regbyte"))
+ {
+ map_byte *ma = NULL;
+
+ mem_free ((void **) &symbol);
+
+ if (get_regbyte (&text, &ma))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ map_byte_append (&g->di->m_regbytes, &ma);
+ }
+ /* .errtext */
+ else if (is_dot && str_equal (symbol, (byte *) "errtext"))
+ {
+ map_str *ma = NULL;
+
+ mem_free ((void **) &symbol);
+
+ if (get_errtext (&text, &ma))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ map_str_append (&g->maps, &ma);
+ }
+ /* .string */
+ else if (is_dot && str_equal (symbol, (byte *) "string"))
+ {
+ mem_free ((void **) &symbol);
+
+ if (g->di->m_string != NULL)
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ if (get_identifier (&text, &g->string_symbol))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ /* skip semicolon */
+ eat_spaces (&text);
+ text++;
+ eat_spaces (&text);
+ }
+ else
+ {
+ rule *ru = NULL;
+ map_rule *ma = NULL;
+
+ if (get_rule (&text, &ru, g->maps, g->mapb))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ rule_append (&g->di->m_rulez, &ru);
+
+ /* if a rule consist of only one specifier, give it an ".and" operator */
+ if (ru->m_oper == op_none)
+ ru->m_oper = op_and;
+
+ map_rule_create (&ma);
+ if (ma == NULL)
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ ma->key = symbol;
+ ma->data = ru;
+ map_rule_append (&g->mapr, &ma);
+ }
+ }
+
+ if (update_dependencies (g->di, g->mapr, &g->syntax_symbol, &g->string_symbol,
+ g->di->m_regbytes))
+ {
+ grammar_load_state_destroy (&g);
+ return 0;
+ }
+
+ dict_append (&g_dicts, &g->di);
+ id = g->di->m_id;
+ g->di = NULL;
+
+ grammar_load_state_destroy (&g);
+
+ return id;
+}
+
+int grammar_set_reg8 (grammar id, const byte *name, byte value)
+{
+ dict *di = NULL;
+ map_byte *reg = NULL;
+
+ clear_last_error ();
+
+ dict_find (&g_dicts, id, &di);
+ if (di == NULL)
+ {
+ set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
+ return 0;
+ }
+
+ reg = map_byte_locate (&di->m_regbytes, name);
+ if (reg == NULL)
+ {
+ set_last_error (INVALID_REGISTER_NAME, str_duplicate (name), -1);
+ return 0;
+ }
+
+ reg->data = value;
+ return 1;
+}
+
+int grammar_check (grammar id, const byte *text, byte **prod, unsigned int *size)
+{
+ dict *di = NULL;
+ barray *ba = NULL;
+ unsigned int index = 0;
+ regbyte_ctx *rbc = NULL;
+
+ clear_last_error ();
+
+ dict_find (&g_dicts, id, &di);
+ if (di == NULL)
+ {
+ set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
+ return 0;
+ }
+
+ barray_create (&ba);
+ if (ba == NULL)
+ return 0;
+
+ *prod = NULL;
+ *size = 0;
+
+ if (match (di, text, &index, di->m_syntax, &ba, 0, &rbc) != mr_matched)
+ {
+ barray_destroy (&ba);
+ free_regbyte_ctx_stack (rbc, NULL);
+ return 0;
+ }
+
+ free_regbyte_ctx_stack (rbc, NULL);
+
+ *prod = mem_alloc (ba->len * sizeof (byte));
+ if (*prod == NULL)
+ {
+ barray_destroy (&ba);
+ return 0;
+ }
+
+ mem_copy (*prod, ba->data, ba->len * sizeof (byte));
+ *size = ba->len;
+ barray_destroy (&ba);
+
+ return 1;
+}
+
+int grammar_destroy (grammar id)
+{
+ dict **di = &g_dicts;
+
+ clear_last_error ();
+
+ while (*di != NULL)
+ {
+ if ((**di).m_id == id)
+ {
+ dict *tmp = *di;
+ *di = (**di).m_next;
+ dict_destroy (&tmp);
+ return 1;
+ }
+
+ di = &(**di).m_next;
+ }
+
+ set_last_error (INVALID_GRAMMAR_ID, NULL, -1);
+ return 0;
+}
+
+void grammar_get_last_error (byte *text, unsigned int size, int *pos)
+{
+ unsigned int len = 0, dots_made = 0;
+ const byte *p = error_message;
+
+ *text = '\0';
+
+#define APPEND_CHARACTER(x) if (dots_made == 0) {\
+ if (len < size - 1) {\
+ text[len++] = (x); text[len] = '\0';\
+ } else {\
+ int i;\
+ for (i = 0; i < 3; i++)\
+ if (--len >= 0)\
+ text[len] = '.';\
+ dots_made = 1;\
+ }\
+ }
+
+ if (p)
+ while (*p)
+ if (*p == '$')
+ {
+ const byte *r = error_param;
+
+ while (*r)
+ {
+ APPEND_CHARACTER(*r)
+ r++;
+ }
+
+ p++;
+ }
+ else
+ {
+ APPEND_CHARACTER(*p)
+ p++;
+ }
+
+ *pos = error_position;
+
+#undef APPEND_CHARACTER
+
+}
+