| char *rcs_lex = "$Id: lex.c,v 2.19 1995/10/13 15:16:25 roberto Exp roberto $"; |
| |
| |
| #include <ctype.h> |
| #include <math.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "mem.h" |
| #include "tree.h" |
| #include "table.h" |
| #include "opcode.h" |
| #include "inout.h" |
| #include "parser.h" |
| #include "ugly.h" |
| |
| #define MINBUFF 260 |
| |
| #define lua_strcmp(a,b) (a[0]<b[0]?(-1):(a[0]>b[0]?(1):strcmp(a,b))) |
| |
| #define next() { current = input(); } |
| #define save(x) { *yytextLast++ = (x); } |
| #define save_and_next() { save(current); next(); } |
| |
| static int current; |
| static char *yytext = NULL; |
| static int textsize = 0; |
| static char *yytextLast; |
| |
| static Input input; |
| |
| void lua_setinput (Input fn) |
| { |
| current = ' '; |
| input = fn; |
| if (yytext == NULL) |
| { |
| textsize = MINBUFF; |
| yytext = newvector(textsize, char); |
| } |
| } |
| |
| char *lua_lasttext (void) |
| { |
| *yytextLast = 0; |
| return yytext; |
| } |
| |
| |
| /* The reserved words must be listed in lexicographic order */ |
| static struct |
| { |
| char *name; |
| int token; |
| } reserved [] = { |
| {"and", AND}, |
| {"do", DO}, |
| {"else", ELSE}, |
| {"elseif", ELSEIF}, |
| {"end", END}, |
| {"function", FUNCTION}, |
| {"if", IF}, |
| {"local", LOCAL}, |
| {"nil", NIL}, |
| {"not", NOT}, |
| {"or", OR}, |
| {"repeat", REPEAT}, |
| {"return", RETURN}, |
| {"then", THEN}, |
| {"until", UNTIL}, |
| {"while", WHILE} }; |
| |
| |
| #define RESERVEDSIZE (sizeof(reserved)/sizeof(reserved[0])) |
| |
| |
| static int findReserved (char *name) |
| { |
| int l = 0; |
| int h = RESERVEDSIZE - 1; |
| while (l <= h) |
| { |
| int m = (l+h)/2; |
| int comp = lua_strcmp(name, reserved[m].name); |
| if (comp < 0) |
| h = m-1; |
| else if (comp == 0) |
| return reserved[m].token; |
| else |
| l = m+1; |
| } |
| return 0; |
| } |
| |
| |
| static void growtext (void) |
| { |
| int size = yytextLast - yytext; |
| textsize *= 2; |
| yytext = growvector(yytext, textsize, char); |
| yytextLast = yytext + size; |
| } |
| |
| |
| static int read_long_string (void) |
| { |
| int cont = 0; |
| int spaceleft = textsize - (yytextLast - yytext); |
| while (1) |
| { |
| if (spaceleft <= 2) /* may read more than 1 char in one cicle */ |
| { |
| growtext(); |
| spaceleft = textsize - (yytextLast - yytext); |
| } |
| switch (current) |
| { |
| case EOF: |
| case 0: |
| return WRONGTOKEN; |
| case '[': |
| save_and_next(); spaceleft--; |
| if (current == '[') |
| { |
| cont++; |
| save_and_next(); spaceleft--; |
| } |
| continue; |
| case ']': |
| save_and_next(); spaceleft--; |
| if (current == ']') |
| { |
| if (cont == 0) return STRING; |
| cont--; |
| save_and_next(); spaceleft--; |
| } |
| continue; |
| case '\n': |
| lua_linenumber++; /* goes through */ |
| default: |
| save_and_next(); spaceleft--; |
| } |
| } |
| } |
| |
| |
| int yylex (void) |
| { |
| float a; |
| static int linelasttoken = 0; |
| if (lua_debug) |
| luaI_codedebugline(linelasttoken); |
| linelasttoken = lua_linenumber; |
| while (1) |
| { |
| yytextLast = yytext; |
| #if 0 |
| fprintf(stderr,"'%c' %d\n",current,current); |
| #endif |
| 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': |
| next(); |
| continue; |
| |
| case '$': |
| next(); |
| while (isalnum(current) || current == '_') |
| save_and_next(); |
| *yytextLast = 0; |
| if (lua_strcmp(yytext, "debug") == 0) |
| { |
| yylval.vInt = 1; |
| return DEBUG; |
| } |
| else if (lua_strcmp(yytext, "nodebug") == 0) |
| { |
| yylval.vInt = 0; |
| return DEBUG; |
| } |
| return WRONGTOKEN; |
| |
| case '-': |
| save_and_next(); |
| if (current != '-') return '-'; /* else goes through */ |
| case '#': |
| do { next(); } while (current != '\n' && current != 0); |
| continue; |
| |
| case '[': |
| save_and_next(); |
| if (current != '[') return '['; |
| else |
| { |
| save_and_next(); /* pass the second '[' */ |
| if (read_long_string() == WRONGTOKEN) |
| return WRONGTOKEN; |
| save_and_next(); /* pass the second ']' */ |
| *(yytextLast-2) = 0; /* erases ']]' */ |
| yylval.vWord = luaI_findconstantbyname(yytext+2); |
| return STRING; |
| } |
| |
| case '=': |
| save_and_next(); |
| if (current != '=') return '='; |
| else { save_and_next(); return EQ; } |
| |
| case '<': |
| save_and_next(); |
| if (current != '=') return '<'; |
| else { save_and_next(); return LE; } |
| |
| case '>': |
| save_and_next(); |
| if (current != '=') return '>'; |
| else { save_and_next(); return GE; } |
| |
| case '~': |
| save_and_next(); |
| if (current != '=') return '~'; |
| else { save_and_next(); return NE; } |
| |
| case '"': |
| case '\'': |
| { |
| int del = current; |
| int spaceleft = textsize - (yytextLast - yytext); |
| next(); /* skip the delimiter */ |
| while (current != del) |
| { |
| if (spaceleft <= 2) /* may read more than 1 char in one cicle */ |
| { |
| growtext(); |
| spaceleft = textsize - (yytextLast - yytext); |
| } |
| spaceleft--; |
| switch (current) |
| { |
| case EOF: |
| case 0: |
| case '\n': |
| return WRONGTOKEN; |
| case '\\': |
| next(); /* do not save the '\' */ |
| switch (current) |
| { |
| case 'n': save('\n'); next(); break; |
| case 't': save('\t'); next(); break; |
| case 'r': save('\r'); next(); break; |
| default : save(current); next(); break; |
| } |
| break; |
| default: |
| save_and_next(); |
| } |
| } |
| next(); /* skip the delimiter */ |
| *yytextLast = 0; |
| yylval.vWord = luaI_findconstantbyname(yytext); |
| return STRING; |
| } |
| |
| case 'a': case 'b': case 'c': case 'd': case 'e': |
| case 'f': case 'g': case 'h': case 'i': case 'j': |
| case 'k': case 'l': case 'm': case 'n': case 'o': |
| case 'p': case 'q': case 'r': case 's': case 't': |
| case 'u': case 'v': case 'w': case 'x': case 'y': |
| case 'z': |
| case 'A': case 'B': case 'C': case 'D': case 'E': |
| case 'F': case 'G': case 'H': case 'I': case 'J': |
| case 'K': case 'L': case 'M': case 'N': case 'O': |
| case 'P': case 'Q': case 'R': case 'S': case 'T': |
| case 'U': case 'V': case 'W': case 'X': case 'Y': |
| case 'Z': |
| case '_': |
| { |
| Word res; |
| do { save_and_next(); } while (isalnum(current) || current == '_'); |
| *yytextLast = 0; |
| res = findReserved(yytext); |
| if (res) return res; |
| yylval.pNode = lua_constcreate(yytext); |
| return NAME; |
| } |
| |
| case '.': |
| save_and_next(); |
| if (current == '.') |
| { |
| save_and_next(); |
| return CONC; |
| } |
| else if (!isdigit(current)) return '.'; |
| /* current is a digit: goes through to number */ |
| a=0.0; |
| goto fraction; |
| |
| 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*a+current-'0'; save_and_next(); } while (isdigit(current)); |
| if (current == '.') save_and_next(); |
| fraction: |
| { float da=0.1; |
| while (isdigit(current)) |
| {a+=(current-'0')*da; da/=10.0; save_and_next()}; |
| if (current == 'e' || current == 'E') |
| { |
| int e=0; |
| int neg; |
| float ea; |
| save_and_next(); |
| neg=(current=='-'); |
| if (current == '+' || current == '-') save_and_next(); |
| if (!isdigit(current)) return WRONGTOKEN; |
| do { e=10*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; |
| } |
| } |
| yylval.vFloat = a; |
| return NUMBER; |
| } |
| |
| case U_and: case U_do: case U_else: case U_elseif: case U_end: |
| case U_function: case U_if: case U_local: case U_nil: case U_not: |
| case U_or: case U_repeat: case U_return: case U_then: |
| case U_until: case U_while: |
| { |
| int old = current; |
| next(); |
| return reserved[old-U_and].token; |
| } |
| |
| case U_eq: next(); return EQ; |
| case U_le: next(); return LE; |
| case U_ge: next(); return GE; |
| case U_ne: next(); return NE; |
| case U_sc: next(); return CONC; |
| |
| default: /* also end of file */ |
| { |
| save_and_next(); |
| return yytext[0]; |
| } |
| } |
| } |
| } |