usr.bin/m4/look.c

   1 /*      $OpenBSD: look.c,v 1.24 2014/12/21 09:33:12 espie Exp $ */
   2
   3 /*
   4  * Copyright (c) 1989, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Ozan Yigit at York University.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 /*
  38  * look.c
  39  * Facility: m4 macro processor
  40  * by: oz
  41  */
  42
  43 #include <sys/types.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <stdint.h>
  47 #include <stddef.h>
  48 #include <string.h>
  49 #include <ohash.h>
  50 #include "mdef.h"
  51 #include "stdd.h"
  52 #include "extern.h"
  53
  54 static void *hash_calloc(size_t, size_t, void *);
  55 static void hash_free(void *, void *);
  56 static void *element_alloc(size_t, void *);
  57 static void setup_definition(struct macro_definition *, const char *,
  58     const char *);
  59 static void free_definition(char *);
  60 static void keep(char *);
  61 static int string_in_use(const char *);
  62
  63 static struct ohash_info macro_info = {
  64         offsetof(struct ndblock, name),
  65         NULL, hash_calloc, hash_free, element_alloc };
  66
  67 struct ohash macros;
  68
  69 /* Support routines for hash tables.  */
  70 void *
  71 hash_calloc(size_t n, size_t s, void *u __unused)
  72 {
  73         void *storage = xcalloc(n, s, "hash alloc");
  74         return storage;
  75 }
  76
  77 void
  78 hash_free(void *p, void *u __unused)
  79 {
  80         free(p);
  81 }
  82
  83 void *
  84 element_alloc(size_t s, void *u __unused)
  85 {
  86         return xalloc(s, "element alloc");
  87 }
  88
  89 void
  90 init_macros(void)
  91 {
  92         ohash_init(&macros, 10, &macro_info);
  93 }
  94
  95 /*
  96  * find name in the hash table
  97  */
  98 ndptr
  99 lookup(const char *name)
 100 {
 101         return ohash_find(&macros, ohash_qlookup(&macros, name));
 102 }
 103
 104 struct macro_definition *
 105 lookup_macro_definition(const char *name)
 106 {
 107         ndptr p;
 108
 109         p = ohash_find(&macros, ohash_qlookup(&macros, name));
 110         if (p)
 111                 return p->d;
 112         else
 113                 return NULL;
 114 }
 115
 116 static void
 117 setup_definition(struct macro_definition *d, const char *defn, const char *name)
 118 {
 119         ndptr p;
 120
 121         if (strncmp(defn, BUILTIN_MARKER, sizeof(BUILTIN_MARKER)-1) == 0 &&
 122             (p = macro_getbuiltin(defn+sizeof(BUILTIN_MARKER)-1)) != NULL) {
 123                 d->type = macro_builtin_type(p);
 124                 d->defn = xstrdup(defn+sizeof(BUILTIN_MARKER)-1);
 125         } else {
 126                 if (!*defn)
 127                         d->defn = __DECONST(char *, null);
 128                 else
 129                         d->defn = xstrdup(defn);
 130                 d->type = MACRTYPE;
 131         }
 132         if (STREQ(name, defn))
 133                 d->type |= RECDEF;
 134 }
 135
 136 static ndptr
 137 create_entry(const char *name)
 138 {
 139         const char *end = NULL;
 140         unsigned int i;
 141         ndptr n;
 142
 143         i = ohash_qlookupi(&macros, name, &end);
 144         n = ohash_find(&macros, i);
 145         if (n == NULL) {
 146                 n = ohash_create_entry(&macro_info, name, &end);
 147                 ohash_insert(&macros, i, n);
 148                 n->trace_flags = FLAG_NO_TRACE;
 149                 n->builtin_type = MACRTYPE;
 150                 n->d = NULL;
 151         }
 152         return n;
 153 }
 154
 155 void
 156 macro_define(const char *name, const char *defn)
 157 {
 158         ndptr n = create_entry(name);
 159         if (n->d != NULL) {
 160                 if (n->d->defn != null)
 161                         free_definition(n->d->defn);
 162         } else {
 163                 n->d = xalloc(sizeof(struct macro_definition), NULL);
 164                 n->d->next = NULL;
 165         }
 166         setup_definition(n->d, defn, name);
 167 }
 168
 169 void
 170 macro_pushdef(const char *name, const char *defn)
 171 {
 172         ndptr n;
 173         struct macro_definition *d;
 174
 175         n = create_entry(name);
 176         d = xalloc(sizeof(struct macro_definition), NULL);
 177         d->next = n->d;
 178         n->d = d;
 179         setup_definition(n->d, defn, name);
 180 }
 181
 182 void
 183 macro_undefine(const char *name)
 184 {
 185         ndptr n = lookup(name);
 186         if (n != NULL) {
 187                 struct macro_definition *r, *r2;
 188
 189                 for (r = n->d; r != NULL; r = r2) {
 190                         r2 = r->next;
 191                         if (r->defn != null)
 192                                 free(r->defn);
 193                         free(r);
 194                 }
 195                 n->d = NULL;
 196         }
 197 }
 198
 199 void
 200 macro_popdef(const char *name)
 201 {
 202         ndptr n = lookup(name);
 203
 204         if (n != NULL) {
 205                 struct macro_definition *r = n->d;
 206                 if (r != NULL) {
 207                         n->d = r->next;
 208                         if (r->defn != null)
 209                                 free(r->defn);
 210                         free(r);
 211                 }
 212         }
 213 }
 214
 215 void
 216 macro_for_all(void (*f)(const char *, struct macro_definition *))
 217 {
 218         ndptr n;
 219         unsigned int i;
 220
 221         for (n = ohash_first(&macros, &i); n != NULL;
 222             n = ohash_next(&macros, &i))
 223                 if (n->d != NULL)
 224                         f(n->name, n->d);
 225 }
 226
 227 void
 228 setup_builtin(const char *name, unsigned int type)
 229 {
 230         ndptr n;
 231         char *name2;
 232
 233         if (prefix_builtins) {
 234                 name2 = xalloc(strlen(name)+3+1, NULL);
 235                 memcpy(name2, "m4_", 3);
 236                 memcpy(name2 + 3, name, strlen(name)+1);
 237         } else
 238                 name2 = xstrdup(name);
 239
 240         n = create_entry(name2);
 241         n->builtin_type = type;
 242         n->d = xalloc(sizeof(struct macro_definition), NULL);
 243         n->d->defn = name2;
 244         n->d->type = type;
 245         n->d->next = NULL;
 246 }
 247
 248 void
 249 mark_traced(const char *name, int on)
 250 {
 251         ndptr p;
 252         unsigned int i;
 253
 254         if (name == NULL) {
 255                 if (on)
 256                         trace_flags |= TRACE_ALL;
 257                 else
 258                         trace_flags &= ~TRACE_ALL;
 259                 for (p = ohash_first(&macros, &i); p != NULL;
 260                     p = ohash_next(&macros, &i))
 261                         p->trace_flags = FLAG_NO_TRACE;
 262         } else {
 263                 p = create_entry(name);
 264                 p->trace_flags = on;
 265         }
 266 }
 267
 268 ndptr
 269 macro_getbuiltin(const char *name)
 270 {
 271         ndptr p;
 272
 273         p = lookup(name);
 274         if (p == NULL || p->builtin_type == MACRTYPE)
 275                 return NULL;
 276         else
 277                 return p;
 278 }
 279
 280 /* XXX things are slightly more complicated than they seem.
 281  * a macro may actually be "live" (in the middle of an expansion
 282  * on the stack.
 283  * So we actually may need to place it in an array for later...
 284  */
 285
 286 static int kept_capacity = 0;
 287 static int kept_size = 0;
 288 static char **kept = NULL;
 289
 290 static void
 291 keep(char *ptr)
 292 {
 293         if (kept_capacity <= kept_size) {
 294                 if (kept_capacity)
 295                         kept_capacity *= 2;
 296                 else
 297                         kept_capacity = 50;
 298                 kept = xreallocarray(kept, kept_capacity,
 299                     sizeof(char *), "Out of memory while saving %d strings\n",
 300                     kept_capacity);
 301         }
 302         kept[kept_size++] = ptr;
 303 }
 304
 305 static int
 306 string_in_use(const char *ptr)
 307 {
 308         int i;
 309         for (i = 0; i <= sp; i++) {
 310                 if (sstack[i] == STORAGE_MACRO && mstack[i].sstr == ptr)
 311                         return 1;
 312                 }
 313         return 0;
 314 }
 315
 316
 317 static void
 318 free_definition(char *ptr)
 319 {
 320         int i;
 321
 322         /* first try to free old strings */
 323         for (i = 0; i < kept_size; i++) {
 324                 if (!string_in_use(kept[i])) {
 325                         kept_size--;
 326                         free(kept[i]);
 327                         if (i != kept_size)
 328                                 kept[i] = kept[kept_size];
 329                         i--;
 330                 }
 331         }
 332
 333         /* then deal with us */
 334         if (string_in_use(ptr))
 335                 keep(ptr);
 336         else
 337                 free(ptr);
 338 }
 339