diff options
author | Michal Krol <[email protected]> | 2004-03-04 13:07:52 +0000 |
---|---|---|
committer | Michal Krol <[email protected]> | 2004-03-04 13:07:52 +0000 |
commit | a904b493a9f86a9cfcfff032255352b7050ef271 (patch) | |
tree | ca70d6c024e2285d90edaa1fd3c19f423862a248 /src/mesa/shader/grammar.c | |
parent | 2462f6bfa0ca71390439104f751310da89a69d1a (diff) |
Added missing Copyrights.
Diffstat (limited to 'src/mesa/shader/grammar.c')
-rw-r--r-- | src/mesa/shader/grammar.c | 5559 |
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 (¶m);
- 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 (®bytes,
- 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 (®bytes, 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 (¶m); + 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 (®bytes, + 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 (®bytes, 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 + +} + |