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-rw-r--r--module/lua/llex.c527
1 files changed, 527 insertions, 0 deletions
diff --git a/module/lua/llex.c b/module/lua/llex.c
new file mode 100644
index 000000000..a7144681c
--- /dev/null
+++ b/module/lua/llex.c
@@ -0,0 +1,527 @@
+/* BEGIN CSTYLED */
+/*
+** $Id: llex.c,v 2.63.1.3 2015/02/09 17:56:34 roberto Exp $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+#define llex_c
+#define LUA_CORE
+
+#include <sys/lua/lua.h>
+
+#include "lctype.h"
+#include "ldo.h"
+#include "llex.h"
+#include "lobject.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "lzio.h"
+
+
+
+#define next(ls) (ls->current = zgetc(ls->z))
+
+
+
+#define currIsNewline(ls) (ls->current == '\n' || ls->current == '\r')
+
+
+/* ORDER RESERVED */
+static const char *const luaX_tokens [] = {
+ "and", "break", "do", "else", "elseif",
+ "end", "false", "for", "function", "goto", "if",
+ "in", "local", "nil", "not", "or", "repeat",
+ "return", "then", "true", "until", "while",
+ "..", "...", "==", ">=", "<=", "~=", "::", "<eof>",
+ "<number>", "<name>", "<string>"
+};
+
+
+#define save_and_next(ls) (save(ls, ls->current), next(ls))
+
+
+static l_noret lexerror (LexState *ls, const char *msg, int token);
+
+
+static void save (LexState *ls, int c) {
+ Mbuffer *b = ls->buff;
+ if (luaZ_bufflen(b) + 1 > luaZ_sizebuffer(b)) {
+ size_t newsize;
+ if (luaZ_sizebuffer(b) >= MAX_SIZET/2)
+ lexerror(ls, "lexical element too long", 0);
+ newsize = luaZ_sizebuffer(b) * 2;
+ luaZ_resizebuffer(ls->L, b, newsize);
+ }
+ b->buffer[luaZ_bufflen(b)++] = cast(char, c);
+}
+
+
+void luaX_init (lua_State *L) {
+ int i;
+ for (i=0; i<NUM_RESERVED; i++) {
+ TString *ts = luaS_new(L, luaX_tokens[i]);
+ luaS_fix(ts); /* reserved words are never collected */
+ ts->tsv.extra = cast_byte(i+1); /* reserved word */
+ }
+}
+
+
+const char *luaX_token2str (LexState *ls, int token) {
+ if (token < FIRST_RESERVED) { /* single-byte symbols? */
+ lua_assert(token == cast(unsigned char, token));
+ return (lisprint(token)) ? luaO_pushfstring(ls->L, LUA_QL("%c"), token) :
+ luaO_pushfstring(ls->L, "char(%d)", token);
+ }
+ else {
+ const char *s = luaX_tokens[token - FIRST_RESERVED];
+ if (token < TK_EOS) /* fixed format (symbols and reserved words)? */
+ return luaO_pushfstring(ls->L, LUA_QS, s);
+ else /* names, strings, and numerals */
+ return s;
+ }
+}
+
+
+static const char *txtToken (LexState *ls, int token) {
+ switch (token) {
+ case TK_NAME:
+ case TK_STRING:
+ case TK_NUMBER:
+ save(ls, '\0');
+ return luaO_pushfstring(ls->L, LUA_QS, luaZ_buffer(ls->buff));
+ default:
+ return luaX_token2str(ls, token);
+ }
+}
+
+
+static l_noret lexerror (LexState *ls, const char *msg, int token) {
+ char buff[LUA_IDSIZE];
+ luaO_chunkid(buff, getstr(ls->source), LUA_IDSIZE);
+ msg = luaO_pushfstring(ls->L, "%s:%d: %s", buff, ls->linenumber, msg);
+ if (token)
+ luaO_pushfstring(ls->L, "%s near %s", msg, txtToken(ls, token));
+ luaD_throw(ls->L, LUA_ERRSYNTAX);
+}
+
+
+l_noret luaX_syntaxerror (LexState *ls, const char *msg) {
+ lexerror(ls, msg, ls->t.token);
+}
+
+
+/*
+** creates a new string and anchors it in function's table so that
+** it will not be collected until the end of the function's compilation
+** (by that time it should be anchored in function's prototype)
+*/
+TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
+ lua_State *L = ls->L;
+ TValue *o; /* entry for `str' */
+ TString *ts = luaS_newlstr(L, str, l); /* create new string */
+ setsvalue2s(L, L->top++, ts); /* temporarily anchor it in stack */
+ o = luaH_set(L, ls->fs->h, L->top - 1);
+ if (ttisnil(o)) { /* not in use yet? (see 'addK') */
+ /* boolean value does not need GC barrier;
+ table has no metatable, so it does not need to invalidate cache */
+ setbvalue(o, 1); /* t[string] = true */
+ luaC_checkGC(L);
+ }
+ else { /* string already present */
+ ts = rawtsvalue(keyfromval(o)); /* re-use value previously stored */
+ }
+ L->top--; /* remove string from stack */
+ return ts;
+}
+
+
+/*
+** increment line number and skips newline sequence (any of
+** \n, \r, \n\r, or \r\n)
+*/
+static void inclinenumber (LexState *ls) {
+ int old = ls->current;
+ lua_assert(currIsNewline(ls));
+ next(ls); /* skip `\n' or `\r' */
+ if (currIsNewline(ls) && ls->current != old)
+ next(ls); /* skip `\n\r' or `\r\n' */
+ if (++ls->linenumber >= MAX_INT)
+ lexerror(ls, "chunk has too many lines", 0);
+}
+
+
+void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source,
+ int firstchar) {
+ ls->decpoint = '.';
+ ls->L = L;
+ ls->current = firstchar;
+ ls->lookahead.token = TK_EOS; /* no look-ahead token */
+ ls->z = z;
+ ls->fs = NULL;
+ ls->linenumber = 1;
+ ls->lastline = 1;
+ ls->source = source;
+ ls->envn = luaS_new(L, LUA_ENV); /* create env name */
+ luaS_fix(ls->envn); /* never collect this name */
+ luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER); /* initialize buffer */
+}
+
+
+
+/*
+** =======================================================
+** LEXICAL ANALYZER
+** =======================================================
+*/
+
+
+
+static int check_next (LexState *ls, const char *set) {
+ if (ls->current == '\0' || !strchr(set, ls->current))
+ return 0;
+ save_and_next(ls);
+ return 1;
+}
+
+
+/*
+** change all characters 'from' in buffer to 'to'
+*/
+static void buffreplace (LexState *ls, char from, char to) {
+ size_t n = luaZ_bufflen(ls->buff);
+ char *p = luaZ_buffer(ls->buff);
+ while (n--)
+ if (p[n] == from) p[n] = to;
+}
+
+
+#if !defined(getlocaledecpoint)
+#define getlocaledecpoint() (localeconv()->decimal_point[0])
+#endif
+
+
+#define buff2d(b,e) luaO_str2d(luaZ_buffer(b), luaZ_bufflen(b) - 1, e)
+
+/*
+** in case of format error, try to change decimal point separator to
+** the one defined in the current locale and check again
+*/
+static void trydecpoint (LexState *ls, SemInfo *seminfo) {
+ char old = ls->decpoint;
+ ls->decpoint = getlocaledecpoint();
+ buffreplace(ls, old, ls->decpoint); /* try new decimal separator */
+ if (!buff2d(ls->buff, &seminfo->r)) {
+ /* format error with correct decimal point: no more options */
+ buffreplace(ls, ls->decpoint, '.'); /* undo change (for error message) */
+ lexerror(ls, "malformed number", TK_NUMBER);
+ }
+}
+
+
+/* LUA_NUMBER */
+/*
+** this function is quite liberal in what it accepts, as 'luaO_str2d'
+** will reject ill-formed numerals.
+*/
+static void read_numeral (LexState *ls, SemInfo *seminfo) {
+ const char *expo = "Ee";
+ int first = ls->current;
+ lua_assert(lisdigit(ls->current));
+ save_and_next(ls);
+ if (first == '0' && check_next(ls, "Xx")) /* hexadecimal? */
+ expo = "Pp";
+ for (;;) {
+ if (check_next(ls, expo)) /* exponent part? */
+ check_next(ls, "+-"); /* optional exponent sign */
+ if (lisxdigit(ls->current) || ls->current == '.')
+ save_and_next(ls);
+ else break;
+ }
+ save(ls, '\0');
+ buffreplace(ls, '.', ls->decpoint); /* follow locale for decimal point */
+ if (!buff2d(ls->buff, &seminfo->r)) /* format error? */
+ trydecpoint(ls, seminfo); /* try to update decimal point separator */
+}
+
+
+/*
+** skip a sequence '[=*[' or ']=*]' and return its number of '='s or
+** -1 if sequence is malformed
+*/
+static int skip_sep (LexState *ls) {
+ int count = 0;
+ int s = ls->current;
+ lua_assert(s == '[' || s == ']');
+ save_and_next(ls);
+ while (ls->current == '=') {
+ save_and_next(ls);
+ count++;
+ }
+ return (ls->current == s) ? count : (-count) - 1;
+}
+
+
+static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
+ save_and_next(ls); /* skip 2nd `[' */
+ if (currIsNewline(ls)) /* string starts with a newline? */
+ inclinenumber(ls); /* skip it */
+ for (;;) {
+ switch (ls->current) {
+ case EOZ:
+ lexerror(ls, (seminfo) ? "unfinished long string" :
+ "unfinished long comment", TK_EOS);
+ break; /* to avoid warnings */
+ case ']': {
+ if (skip_sep(ls) == sep) {
+ save_and_next(ls); /* skip 2nd `]' */
+ goto endloop;
+ }
+ break;
+ }
+ case '\n': case '\r': {
+ save(ls, '\n');
+ inclinenumber(ls);
+ if (!seminfo) luaZ_resetbuffer(ls->buff); /* avoid wasting space */
+ break;
+ }
+ default: {
+ if (seminfo) save_and_next(ls);
+ else next(ls);
+ }
+ }
+ } endloop:
+ if (seminfo)
+ seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + (2 + sep),
+ luaZ_bufflen(ls->buff) - 2*(2 + sep));
+}
+
+
+static void escerror (LexState *ls, int *c, int n, const char *msg) {
+ int i;
+ luaZ_resetbuffer(ls->buff); /* prepare error message */
+ save(ls, '\\');
+ for (i = 0; i < n && c[i] != EOZ; i++)
+ save(ls, c[i]);
+ lexerror(ls, msg, TK_STRING);
+}
+
+
+static int readhexaesc (LexState *ls) {
+ int c[3], i; /* keep input for error message */
+ int r = 0; /* result accumulator */
+ c[0] = 'x'; /* for error message */
+ for (i = 1; i < 3; i++) { /* read two hexadecimal digits */
+ c[i] = next(ls);
+ if (!lisxdigit(c[i]))
+ escerror(ls, c, i + 1, "hexadecimal digit expected");
+ r = (r << 4) + luaO_hexavalue(c[i]);
+ }
+ return r;
+}
+
+
+static int readdecesc (LexState *ls) {
+ int c[3], i;
+ int r = 0; /* result accumulator */
+ for (i = 0; i < 3 && lisdigit(ls->current); i++) { /* read up to 3 digits */
+ c[i] = ls->current;
+ r = 10*r + c[i] - '0';
+ next(ls);
+ }
+ if (r > UCHAR_MAX)
+ escerror(ls, c, i, "decimal escape too large");
+ return r;
+}
+
+
+static void read_string (LexState *ls, int del, SemInfo *seminfo) {
+ save_and_next(ls); /* keep delimiter (for error messages) */
+ while (ls->current != del) {
+ switch (ls->current) {
+ case EOZ:
+ lexerror(ls, "unfinished string", TK_EOS);
+ break; /* to avoid warnings */
+ case '\n':
+ case '\r':
+ lexerror(ls, "unfinished string", TK_STRING);
+ break; /* to avoid warnings */
+ case '\\': { /* escape sequences */
+ int c; /* final character to be saved */
+ next(ls); /* do not save the `\' */
+ switch (ls->current) {
+ case 'a': c = '\a'; goto read_save;
+ case 'b': c = '\b'; goto read_save;
+ case 'f': c = '\f'; goto read_save;
+ case 'n': c = '\n'; goto read_save;
+ case 'r': c = '\r'; goto read_save;
+ case 't': c = '\t'; goto read_save;
+ case 'v': c = '\v'; goto read_save;
+ case 'x': c = readhexaesc(ls); goto read_save;
+ case '\n': case '\r':
+ inclinenumber(ls); c = '\n'; goto only_save;
+ case '\\': case '\"': case '\'':
+ c = ls->current; goto read_save;
+ case EOZ: goto no_save; /* will raise an error next loop */
+ case 'z': { /* zap following span of spaces */
+ next(ls); /* skip the 'z' */
+ while (lisspace(ls->current)) {
+ if (currIsNewline(ls)) inclinenumber(ls);
+ else next(ls);
+ }
+ goto no_save;
+ }
+ default: {
+ if (!lisdigit(ls->current))
+ escerror(ls, &ls->current, 1, "invalid escape sequence");
+ /* digital escape \ddd */
+ c = readdecesc(ls);
+ goto only_save;
+ }
+ }
+ read_save: next(ls); /* read next character */
+ only_save: save(ls, c); /* save 'c' */
+ no_save: break;
+ }
+ default:
+ save_and_next(ls);
+ }
+ }
+ save_and_next(ls); /* skip delimiter */
+ seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + 1,
+ luaZ_bufflen(ls->buff) - 2);
+}
+
+
+static int llex (LexState *ls, SemInfo *seminfo) {
+ luaZ_resetbuffer(ls->buff);
+ for (;;) {
+ switch (ls->current) {
+ case '\n': case '\r': { /* line breaks */
+ inclinenumber(ls);
+ break;
+ }
+ case ' ': case '\f': case '\t': case '\v': { /* spaces */
+ next(ls);
+ break;
+ }
+ case '-': { /* '-' or '--' (comment) */
+ next(ls);
+ if (ls->current != '-') return '-';
+ /* else is a comment */
+ next(ls);
+ if (ls->current == '[') { /* long comment? */
+ int sep = skip_sep(ls);
+ luaZ_resetbuffer(ls->buff); /* `skip_sep' may dirty the buffer */
+ if (sep >= 0) {
+ read_long_string(ls, NULL, sep); /* skip long comment */
+ luaZ_resetbuffer(ls->buff); /* previous call may dirty the buff. */
+ break;
+ }
+ }
+ /* else short comment */
+ while (!currIsNewline(ls) && ls->current != EOZ)
+ next(ls); /* skip until end of line (or end of file) */
+ break;
+ }
+ case '[': { /* long string or simply '[' */
+ int sep = skip_sep(ls);
+ if (sep >= 0) {
+ read_long_string(ls, seminfo, sep);
+ return TK_STRING;
+ }
+ else if (sep == -1) return '[';
+ else lexerror(ls, "invalid long string delimiter", TK_STRING);
+ }
+ case '=': {
+ next(ls);
+ if (ls->current != '=') return '=';
+ else { next(ls); return TK_EQ; }
+ }
+ case '<': {
+ next(ls);
+ if (ls->current != '=') return '<';
+ else { next(ls); return TK_LE; }
+ }
+ case '>': {
+ next(ls);
+ if (ls->current != '=') return '>';
+ else { next(ls); return TK_GE; }
+ }
+ case '~': {
+ next(ls);
+ if (ls->current != '=') return '~';
+ else { next(ls); return TK_NE; }
+ }
+ case ':': {
+ next(ls);
+ if (ls->current != ':') return ':';
+ else { next(ls); return TK_DBCOLON; }
+ }
+ case '"': case '\'': { /* short literal strings */
+ read_string(ls, ls->current, seminfo);
+ return TK_STRING;
+ }
+ case '.': { /* '.', '..', '...', or number */
+ save_and_next(ls);
+ if (check_next(ls, ".")) {
+ if (check_next(ls, "."))
+ return TK_DOTS; /* '...' */
+ else return TK_CONCAT; /* '..' */
+ }
+ else if (!lisdigit(ls->current)) return '.';
+ /* else go through */
+ }
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9': {
+ read_numeral(ls, seminfo);
+ return TK_NUMBER;
+ }
+ case EOZ: {
+ return TK_EOS;
+ }
+ default: {
+ if (lislalpha(ls->current)) { /* identifier or reserved word? */
+ TString *ts;
+ do {
+ save_and_next(ls);
+ } while (lislalnum(ls->current));
+ ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
+ luaZ_bufflen(ls->buff));
+ seminfo->ts = ts;
+ if (isreserved(ts)) /* reserved word? */
+ return ts->tsv.extra - 1 + FIRST_RESERVED;
+ else {
+ return TK_NAME;
+ }
+ }
+ else { /* single-char tokens (+ - / ...) */
+ int c = ls->current;
+ next(ls);
+ return c;
+ }
+ }
+ }
+ }
+}
+
+
+void luaX_next (LexState *ls) {
+ ls->lastline = ls->linenumber;
+ if (ls->lookahead.token != TK_EOS) { /* is there a look-ahead token? */
+ ls->t = ls->lookahead; /* use this one */
+ ls->lookahead.token = TK_EOS; /* and discharge it */
+ }
+ else
+ ls->t.token = llex(ls, &ls->t.seminfo); /* read next token */
+}
+
+
+int luaX_lookahead (LexState *ls) {
+ lua_assert(ls->lookahead.token == TK_EOS);
+ ls->lookahead.token = llex(ls, &ls->lookahead.seminfo);
+ return ls->lookahead.token;
+}
+/* END CSTYLED */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-13 16:41:39 +0000