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-rw-r--r--src/lua/llex.c411
1 files changed, 411 insertions, 0 deletions
diff --git a/src/lua/llex.c b/src/lua/llex.c
new file mode 100644
index 00000000..86fb69ab
--- /dev/null
+++ b/src/lua/llex.c
@@ -0,0 +1,411 @@
+/*
+** $Id: llex.c,v 1.6 2004/06/04 13:42:10 neil Exp $
+** Lexical Analyzer
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "luadebug.h"
+#include "lzio.h"
+
+
+
+#define next(LS) (LS->current = zgetc(LS->z))
+
+
+
+/* ORDER RESERVED */
+static const char *const token2string [] = {
+ "and", "break", "do", "else", "elseif", "end", "for",
+ "function", "if", "local", "nil", "not", "or", "repeat", "return", "then",
+ "until", "while", "", "..", "...", "==", ">=", "<=", "~=", "", "", "<eof>"};
+
+
+void luaX_init (lua_State *L) {
+ int i;
+ for (i=0; i<NUM_RESERVED; i++) {
+ TString *ts = luaS_new(L, token2string[i]);
+ ts->marked = (unsigned char)(RESERVEDMARK+i); /* reserved word */
+ }
+}
+
+
+#define MAXSRC 80
+
+
+void luaX_checklimit (LexState *ls, int val, int limit, const char *msg) {
+ if (val > limit) {
+ char buff[100];
+ sprintf(buff, "too many %.50s (limit=%d)", msg, limit);
+ luaX_error(ls, buff, ls->t.token);
+ }
+}
+
+
+void luaX_syntaxerror (LexState *ls, const char *s, const char *token) {
+ char buff[MAXSRC];
+ luaO_chunkid(buff, ls->source->str, sizeof(buff));
+ luaO_verror(ls->L, "%.99s;\n last token read: `%.30s' at line %d in %.80s",
+ s, token, ls->linenumber, buff);
+}
+
+
+void luaX_error (LexState *ls, const char *s, int token) {
+ char buff[TOKEN_LEN];
+ luaX_token2str(token, buff);
+ if (buff[0] == '\0')
+ luaX_syntaxerror(ls, s, ls->L->Mbuffer);
+ else
+ luaX_syntaxerror(ls, s, buff);
+}
+
+
+void luaX_token2str (int token, char *s) {
+ if (token < 256) {
+ s[0] = (char)token;
+ s[1] = '\0';
+ }
+ else
+ strcpy(s, token2string[token-FIRST_RESERVED]);
+}
+
+
+static void luaX_invalidchar (LexState *ls, int c) {
+ char buff[8];
+ sprintf(buff, "0x%02X", c);
+ luaX_syntaxerror(ls, "invalid control char", buff);
+}
+
+
+static void inclinenumber (LexState *LS) {
+ next(LS); /* skip '\n' */
+ ++LS->linenumber;
+ luaX_checklimit(LS, LS->linenumber, MAX_INT, "lines in a chunk");
+}
+
+
+void luaX_setinput (lua_State *L, LexState *LS, ZIO *z, TString *source) {
+ LS->L = L;
+ LS->lookahead.token = TK_EOS; /* no look-ahead token */
+ LS->z = z;
+ LS->fs = NULL;
+ LS->linenumber = 1;
+ LS->lastline = 1;
+ LS->source = source;
+ next(LS); /* read first char */
+ if (LS->current == '#') {
+ do { /* skip first line */
+ next(LS);
+ } while (LS->current != '\n' && LS->current != '\r' && LS->current != EOZ);
+ }
+}
+
+
+
+/*
+** =======================================================
+** LEXICAL ANALYZER
+** =======================================================
+*/
+
+
+/* use Mbuffer to store names, literal strings and numbers */
+
+#define EXTRABUFF 128
+#define checkbuffer(L, n, len) if ((len)+(n) > L->Mbuffsize) \
+ luaO_openspace(L, (len)+(n)+EXTRABUFF)
+
+#define save(L, c, l) (L->Mbuffer[l++] = (char)c)
+#define save_and_next(L, LS, l) (save(L, LS->current, l), next(LS))
+
+
+static const char *readname (LexState *LS) {
+ lua_State *L = LS->L;
+ size_t l = 0;
+ checkbuffer(L, 10, l);
+ do {
+ checkbuffer(L, 10, l);
+ save_and_next(L, LS, l);
+ } while (isalnum(LS->current) || LS->current == '_');
+ save(L, '\0', l);
+ return L->Mbuffer;
+}
+
+
+/* LUA_NUMBER */
+static void read_number (LexState *LS, int comma, SemInfo *seminfo) {
+ lua_State *L = LS->L;
+ size_t l = 0;
+ checkbuffer(L, 10, l);
+ if (comma) save(L, '.', l);
+ while (isdigit(LS->current)) {
+ checkbuffer(L, 10, l);
+ save_and_next(L, LS, l);
+ }
+ if (LS->current == '.') {
+ save_and_next(L, LS, l);
+ if (LS->current == '.') {
+ save_and_next(L, LS, l);
+ save(L, '\0', l);
+ luaX_error(LS, "ambiguous syntax"
+ " (decimal point x string concatenation)", TK_NUMBER);
+ }
+ }
+ while (isdigit(LS->current)) {
+ checkbuffer(L, 10, l);
+ save_and_next(L, LS, l);
+ }
+ if (LS->current == 'e' || LS->current == 'E') {
+ save_and_next(L, LS, l); /* read 'E' */
+ if (LS->current == '+' || LS->current == '-')
+ save_and_next(L, LS, l); /* optional exponent sign */
+ while (isdigit(LS->current)) {
+ checkbuffer(L, 10, l);
+ save_and_next(L, LS, l);
+ }
+ }
+ save(L, '\0', l);
+ if (!luaO_str2d(L->Mbuffer, &seminfo->r))
+ luaX_error(LS, "malformed number", TK_NUMBER);
+}
+
+
+static void read_long_string (LexState *LS, SemInfo *seminfo) {
+ lua_State *L = LS->L;
+ int cont = 0;
+ size_t l = 0;
+ checkbuffer(L, 10, l);
+ save(L, '[', l); /* save first '[' */
+ save_and_next(L, LS, l); /* pass the second '[' */
+ for (;;) {
+ checkbuffer(L, 10, l);
+ switch (LS->current) {
+ case EOZ:
+ save(L, '\0', l);
+ if (seminfo)
+ luaX_error(LS, "unfinished long string", TK_STRING);
+ else
+ luaX_error(LS, "unfinished comment", TK_EOS);
+ break; /* to avoid warnings */
+ case '[':
+ save_and_next(L, LS, l);
+ if (LS->current == '[') {
+ cont++;
+ save_and_next(L, LS, l);
+ }
+ continue;
+ case ']':
+ save_and_next(L, LS, l);
+ if (LS->current == ']') {
+ if (cont == 0) goto endloop;
+ cont--;
+ save_and_next(L, LS, l);
+ }
+ continue;
+ case '\n':
+ save(L, '\n', l);
+ inclinenumber(LS);
+ if (LS->current == '\r') next(LS);
+ continue;
+ case '\r':
+ save(L, '\n', l);
+ inclinenumber(LS);
+ if (LS->current == '\n') next(LS);
+ continue;
+ default:
+ if (seminfo) /* no need to save complete comment */
+ save(L, LS->current, l);
+ next(LS);
+ }
+ } endloop:
+ save_and_next(L, LS, l); /* skip the second ']' */
+ save(L, '\0', l);
+ if (seminfo)
+ seminfo->ts = luaS_newlstr(L, L->Mbuffer+2, l-5);
+}
+
+
+static void read_string (LexState *LS, int del, SemInfo *seminfo) {
+ lua_State *L = LS->L;
+ size_t l = 0;
+ checkbuffer(L, 10, l);
+ save_and_next(L, LS, l);
+ while (LS->current != del) {
+ checkbuffer(L, 10, l);
+ switch (LS->current) {
+ case EOZ: case '\n': case '\r':
+ save(L, '\0', l);
+ luaX_error(LS, "unfinished string", TK_STRING);
+ break; /* to avoid warnings */
+ case '\\':
+ next(LS); /* do not save the '\' */
+ switch (LS->current) {
+ case 'a': save(L, '\a', l); next(LS); break;
+ case 'b': save(L, '\b', l); next(LS); break;
+ case 'f': save(L, '\f', l); next(LS); break;
+ case 'n': save(L, '\n', l); next(LS); break;
+ case 'r': save(L, '\r', l); next(LS); break;
+ case 't': save(L, '\t', l); next(LS); break;
+ case 'v': save(L, '\v', l); next(LS); break;
+ case '\n':
+ save(L, '\n', l);
+ inclinenumber(LS);
+ if (LS->current == '\r') next(LS);
+ break;
+ case '\r':
+ save(L, '\n', l);
+ inclinenumber(LS);
+ if (LS->current == '\n') next(LS);
+ break;
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9': {
+ int c = 0;
+ int i = 0;
+ do {
+ c = 10*c + (LS->current-'0');
+ next(LS);
+ } while (++i<3 && isdigit(LS->current));
+ if (c != (unsigned char)c) {
+ save(L, '\0', l);
+ luaX_error(LS, "escape sequence too large", TK_STRING);
+ }
+ save(L, c, l);
+ break;
+ }
+ default: /* handles \\, \", \', and \? */
+ save_and_next(L, LS, l);
+ }
+ break;
+ default:
+ save_and_next(L, LS, l);
+ }
+ }
+ save_and_next(L, LS, l); /* skip delimiter */
+ save(L, '\0', l);
+ seminfo->ts = luaS_newlstr(L, L->Mbuffer+1, l-3);
+}
+
+
+int luaX_lex (LexState *LS, SemInfo *seminfo) {
+ for (;;) {
+ switch (LS->current) {
+
+ case ' ': case '\t':
+ next(LS);
+ continue;
+
+ case '\n':
+ inclinenumber(LS);
+ if (LS->current == '\r') next(LS);
+ continue;
+
+ case '\r':
+ inclinenumber(LS);
+ if (LS->current == '\n') next(LS);
+ continue;
+
+ case '$':
+ luaX_error(LS, "unexpected `$' (pragmas are no longer supported)", '$');
+ break;
+
+ case '-':
+ next(LS);
+ if (LS->current != '-') return '-';
+ if (next(LS) == '[' && next(LS) == '[')
+ read_long_string(LS, NULL);
+ else
+ while (LS->current != '\n' && LS->current != '\r' && LS->current != EOZ)
+ next(LS);
+ continue;
+
+ case '[':
+ next(LS);
+ if (LS->current != '[') return '[';
+ else {
+ read_long_string(LS, seminfo);
+ return 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 '"':
+ case '\'':
+ read_string(LS, LS->current, seminfo);
+ return TK_STRING;
+
+ case '.':
+ next(LS);
+ if (LS->current == '.') {
+ next(LS);
+ if (LS->current == '.') {
+ next(LS);
+ return TK_DOTS; /* ... */
+ }
+ else return TK_CONCAT; /* .. */
+ }
+ else if (!isdigit(LS->current)) return '.';
+ else {
+ read_number(LS, 1, seminfo);
+ return TK_NUMBER;
+ }
+
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ read_number(LS, 0, seminfo);
+ return TK_NUMBER;
+
+ case EOZ:
+ return TK_EOS;
+
+ case '_': goto tname;
+
+ default:
+ if (!isalpha(LS->current)) {
+ int c = LS->current;
+ if (iscntrl(c))
+ luaX_invalidchar(LS, c);
+ next(LS);
+ return c;
+ }
+ tname: { /* identifier or reserved word */
+ TString *ts = luaS_new(LS->L, readname(LS));
+ if (ts->marked >= RESERVEDMARK) /* reserved word? */
+ return ts->marked-RESERVEDMARK+FIRST_RESERVED;
+ seminfo->ts = ts;
+ return TK_NAME;
+ }
+ }
+ }
+}
+
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