src/parse.c

   1 /*
   2  * Copyright 1993, 2000 Christopher Seiwald.
   3  * This file is part of Jam - see jam.c for Copyright information.
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 /*
  19  * parse.c - make and destroy parse trees as driven by the parser
  20  */
  21 #include "jam.h"
  22 #include "lists.h"
  23 #include "parse.h"
  24 #include "scan.h"
  25 #include "newstr.h"
  26
  27
  28 static PARSE *yypsave;
  29
  30
  31 #include "jamgram.c"
  32
  33
  34 static int yyparse (void) {
  35   int tk;
  36   void *pp = ParseAlloc(malloc);
  37 #ifndef NDEBUG
  38   /*ParseTrace(stderr, "**");*/
  39 #endif
  40   do {
  41     tk = yylex();
  42     Parse(pp, tk, yylval);
  43   } while (tk != 0);
  44   ParseFree(pp, free);
  45   return 0;
  46 }
  47
  48
  49 void parse_file (const char *f) {
  50   /* suspend scan of current file and push this new file in the stream */
  51   yyfparse(f);
  52   /* now parse each block of rules and execute it */
  53   /* execute it outside of the parser so that recursive */
  54   /* calls to yyrun() work (no recursive yyparse's) */
  55   for (;;) {
  56     LOL l;
  57     PARSE *p;
  58     int jmp = 0; /* JMP_NONE */
  59     /* $(<) and $(>) empty in outer scope */
  60     lol_init(&l);
  61     /* filled by yyparse() calling parse_save() */
  62     yypsave = 0;
  63     /* if parse error or empty parse, outta here */
  64     if (yyparse() || !(p = yypsave)) break;
  65     /* run the parse tree */
  66     list_free((*(p->func))(p, &l, &jmp));
  67     parse_free(p);
  68   }
  69 }
  70
  71
  72 void parse_save (PARSE *p) {
  73   yypsave = p;
  74 }
  75
  76
  77 PARSE *parse_make (
  78   LIST *(*func) (PARSE *p, LOL *args, int *jmp),
  79   PARSE *left,
  80   PARSE *right,
  81   PARSE *third,
  82   const char *string,
  83   const char *string1,
  84   int num)
  85 {
  86   PARSE *p = (PARSE *)malloc(sizeof(PARSE));
  87   p->func = func;
  88   p->left = left;
  89   p->right = right;
  90   p->third = third;
  91   p->string = string;
  92   p->string1 = string1;
  93   p->num = num;
  94   p->refs = 1;
  95   return p;
  96 }
  97
  98
  99 void parse_refer (PARSE *p) {
 100   ++p->refs;
 101 }
 102
 103
 104 void parse_free (PARSE *p) {
 105   if (--p->refs) return;
 106   if (p->string) freestr(p->string);
 107   if (p->string1) freestr(p->string1);
 108   if (p->left) parse_free(p->left);
 109   if (p->right) parse_free(p->right);
 110   if (p->third) parse_free(p->third);
 111   free((char *)p);
 112 }
 113
 114
 115 JAMFA_CONST const char *multiform_suffix (int cnt) {
 116   return (cnt == 1 ? "" : "s");
 117 }