diff options
Diffstat (limited to 'src/lex.c')
| -rw-r--r-- | src/lex.c | 213 |
1 files changed, 114 insertions, 99 deletions
@@ -1,5 +1,5 @@ -char *rcs_lex = "$Id: lex.c,v 2.32 1996/03/21 16:33:47 roberto Exp $"; - +char *rcs_lex = "$Id: lex.c,v 2.39 1996/11/08 19:08:30 roberto Exp $"; + #include <ctype.h> #include <string.h> @@ -14,32 +14,31 @@ char *rcs_lex = "$Id: lex.c,v 2.32 1996/03/21 16:33:47 roberto Exp $"; #define MINBUFF 260 -#define next() { current = input(); } -#define save(x) { *yytextLast++ = (x); } -#define save_and_next() { save(current); next(); } +#define next() (current = input()) +#define save(x) (yytext[tokensize++] = (x)) +#define save_and_next() (save(current), next()) + -static int current; -static char *yytext = NULL; -static int textsize = 0; -static char *yytextLast; +static int current; /* look ahead character */ +static Input input; /* input function */ -static Input input; void lua_setinput (Input fn) { - current = ' '; + current = '\n'; + lua_linenumber = 0; input = fn; - if (yytext == NULL) - { - textsize = MINBUFF; - yytext = newvector(textsize, char); - } } -char *lua_lasttext (void) +void luaI_syntaxerror (char *s) { - *yytextLast = 0; - return yytext; + char msg[256]; + char *token = luaI_buffer(1); + if (token[0] == 0) + token = "<eof>"; + sprintf (msg,"%s;\n> last token read: \"%s\" at line %d in file %s", + s, token, lua_linenumber, lua_parsedfile); + lua_error (msg); } @@ -79,95 +78,97 @@ void luaI_addReserved (void) } } - -static void growtext (void) +static int inclinenumber (int pragma_allowed) { - int size = yytextLast - yytext; - textsize = growvector(&yytext, textsize, char, lexEM, MAX_WORD); - yytextLast = yytext + size; + ++lua_linenumber; + if (pragma_allowed && current == '$') { /* is a pragma? */ + char *buff = luaI_buffer(MINBUFF+1); + int i = 0; + next(); /* skip $ */ + while (isalnum(current)) { + if (i >= MINBUFF) luaI_syntaxerror("pragma too long"); + buff[i++] = current; + next(); + } + buff[i] = 0; + if (strcmp(buff, "debug") == 0) + lua_debug = 1; + else if (strcmp(buff, "nodebug") == 0) + lua_debug = 0; + else luaI_syntaxerror("invalid pragma"); + } + return lua_linenumber; } - -static int read_long_string (void) +static int read_long_string (char *yytext, int buffsize) { int cont = 0; - int spaceleft = textsize - (yytextLast - yytext); + int tokensize = 2; /* '[[' already stored */ while (1) { - if (spaceleft <= 2) /* may read more than 1 char in one cicle */ - { - growtext(); - spaceleft = textsize - (yytextLast - yytext); - } + if (buffsize-tokensize <= 2) /* may read more than 1 char in one cicle */ + yytext = luaI_buffer(buffsize *= 2); switch (current) { - case EOF: case 0: + save(0); return WRONGTOKEN; case '[': - save_and_next(); spaceleft--; + save_and_next(); if (current == '[') { cont++; - save_and_next(); spaceleft--; + save_and_next(); } - continue; + continue; case ']': - save_and_next(); spaceleft--; + save_and_next(); if (current == ']') { - if (cont == 0) return STRING; + if (cont == 0) goto endloop; cont--; - save_and_next(); spaceleft--; + save_and_next(); } - continue; + continue; case '\n': - lua_linenumber++; /* goes through */ + save_and_next(); + inclinenumber(0); + continue; default: - save_and_next(); spaceleft--; + save_and_next(); } - } + } endloop: + save_and_next(); /* pass the second ']' */ + yytext[tokensize-2] = 0; /* erases ']]' */ + luaY_lval.vWord = luaI_findconstantbyname(yytext+2); + yytext[tokensize-2] = ']'; /* restores ']]' */ + save(0); + return STRING; } - int luaY_lex (void) { - double a; static int linelasttoken = 0; + double a; + int buffsize = MINBUFF; + char *yytext = luaI_buffer(buffsize); + yytext[1] = yytext[2] = yytext[3] = 0; if (lua_debug) luaI_codedebugline(linelasttoken); linelasttoken = lua_linenumber; while (1) { - yytextLast = yytext; + int tokensize = 0; switch (current) { - case EOF: - case 0: - return 0; - case '\n': linelasttoken = ++lua_linenumber; - case ' ': - case '\r': /* CR: to avoid problems with DOS/Windows */ - case '\t': + case '\n': next(); + linelasttoken = inclinenumber(1); continue; - case '$': - next(); - while (isalnum(current) || current == '_') - save_and_next(); - *yytextLast = 0; - if (strcmp(yytext, "debug") == 0) - { - luaY_lval.vInt = 1; - return DEBUG; - } - else if (strcmp(yytext, "nodebug") == 0) - { - luaY_lval.vInt = 0; - return DEBUG; - } - return WRONGTOKEN; + case ' ': case '\t': case '\r': /* CR: to avoid problems with DOS */ + next(); + continue; case '-': save_and_next(); @@ -181,12 +182,7 @@ int luaY_lex (void) else { save_and_next(); /* pass the second '[' */ - if (read_long_string() == WRONGTOKEN) - return WRONGTOKEN; - save_and_next(); /* pass the second ']' */ - *(yytextLast-2) = 0; /* erases ']]' */ - luaY_lval.vWord = luaI_findconstantbyname(yytext+2); - return STRING; + return read_long_string(yytext, buffsize); } case '=': @@ -213,21 +209,16 @@ int luaY_lex (void) case '\'': { int del = current; - int spaceleft = textsize - (yytextLast - yytext); - next(); /* skip the delimiter */ + save_and_next(); while (current != del) { - if (spaceleft <= 2) /* may read more than 1 char in one cicle */ - { - growtext(); - spaceleft = textsize - (yytextLast - yytext); - } - spaceleft--; + if (buffsize-tokensize <= 2) /* may read more than 1 char in one cicle */ + yytext = luaI_buffer(buffsize *= 2); switch (current) { - case EOF: case 0: case '\n': + save(0); return WRONGTOKEN; case '\\': next(); /* do not save the '\' */ @@ -236,17 +227,19 @@ int luaY_lex (void) case 'n': save('\n'); next(); break; case 't': save('\t'); next(); break; case 'r': save('\r'); next(); break; - case '\n': lua_linenumber++; /* goes through */ - default : save(current); next(); break; + case '\n': save_and_next(); inclinenumber(0); break; + default : save_and_next(); break; } break; default: save_and_next(); } } - next(); /* skip the delimiter */ - *yytextLast = 0; - luaY_lval.vWord = luaI_findconstantbyname(yytext); + next(); /* skip delimiter */ + save(0); + luaY_lval.vWord = luaI_findconstantbyname(yytext+1); + tokensize--; + save(del); save(0); /* restore delimiter */ return STRING; } @@ -266,7 +259,7 @@ int luaY_lex (void) { TaggedString *ts; do { save_and_next(); } while (isalnum(current) || current == '_'); - *yytextLast = 0; + save(0); ts = lua_createstring(yytext); if (ts->marked > 2) return ts->marked; /* reserved word */ @@ -280,7 +273,12 @@ int luaY_lex (void) if (current == '.') { save_and_next(); - return CONC; + if (current == '.') + { + save_and_next(); + return DOTS; /* ... */ + } + else return CONC; /* .. */ } else if (!isdigit(current)) return '.'; /* current is a digit: goes through to number */ @@ -290,12 +288,24 @@ int luaY_lex (void) case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': a=0.0; - do { a=10.0*a+(current-'0'); save_and_next(); } while (isdigit(current)); - if (current == '.') save_and_next(); -fraction: + do { + a=10.0*a+(current-'0'); + save_and_next(); + } while (isdigit(current)); + if (current == '.') { + save_and_next(); + if (current == '.') + luaI_syntaxerror( + "ambiguous syntax (decimal point x string concatenation)"); + } + fraction: { double da=0.1; while (isdigit(current)) - {a+=(current-'0')*da; da/=10.0; save_and_next()}; + { + a+=(current-'0')*da; + da/=10.0; + save_and_next(); + } if (current == 'e' || current == 'E') { int e=0; @@ -304,19 +314,23 @@ fraction: save_and_next(); neg=(current=='-'); if (current == '+' || current == '-') save_and_next(); - if (!isdigit(current)) return WRONGTOKEN; - do { e=10.0*e+(current-'0'); save_and_next(); } while (isdigit(current)); - for (ea=neg?0.1:10.0; e>0; e>>=1) + if (!isdigit(current)) { save(0); return WRONGTOKEN; } + do { + e=10.0*e+(current-'0'); + save_and_next(); + } while (isdigit(current)); + for (ea=neg?0.1:10.0; e>0; e>>=1) { if (e & 1) a*=ea; ea*=ea; } } luaY_lval.vFloat = a; + save(0); return NUMBER; } - default: /* also end of file */ + default: /* also end of program (0) */ { save_and_next(); return yytext[0]; @@ -324,3 +338,4 @@ fraction: } } } + |