rules.c

   1 /*
   2  * Copyright 1993, 1995 Christopher Seiwald.
   3  *
   4  * This file is part of Jam - see jam.c for Copyright information.
   5  */
   6 /*
   7  * rules.c - access to RULEs, TARGETs, and ACTIONs
   8  *
   9  * External routines:
  10  *
  11  *    bindrule() - return pointer to RULE, creating it if necessary
  12  *    bindtarget() - return pointer to TARGET, creating it if necessary
  13  *    copytarget() - make a new target with the old target's name
  14  *    touchtarget() - mark a target to simulate being new
  15  *    targetlist() - turn list of target names into a TARGET chain
  16  *    targetentry() - add a TARGET to a chain of TARGETS
  17  *    targetchain() - append two TARGET chains
  18  *    actionlist() - append to an ACTION chain
  19  *    addsettings() - add a deferred "set" command to a target
  20  *    copysettings() - copy a settings list for temp use
  21  *    pushsettings() - set all target specific variables
  22  *    popsettings() - reset target specific variables to their pre-push values
  23  *    freesettings() - delete a settings list
  24  *    donerules() - free RULE and TARGET tables
  25  *
  26  * 04/12/94 (seiwald) - actionlist() now just appends a single action.
  27  * 08/23/94 (seiwald) - Support for '+=' (append to variable)
  28  * 06/21/02 (seiwald) - support for named parameters
  29  * 11/04/02 (seiwald) - const-ing for string literals
  30  * 12/03/02 (seiwald) - fix odd includes support by grafting them onto depends
  31  * 12/17/02 (seiwald) - new copysettings() to protect target-specific vars
  32  * 01/14/03 (seiwald) - fix includes fix with new internal includes TARGET
  33  */
  34 #include "jam.h"
  35 #include "lists.h"
  36 #include "parse.h"
  37 #include "variable.h"
  38 #include "rules.h"
  39 #include "newstr.h"
  40 #include "hash.h"
  41
  42 static struct hash *rulehash = NULL;
  43 static struct hash *targethash = NULL;
  44
  45
  46 /*
  47  * bindrule() - return pointer to RULE, creating it if necessary
  48  */
  49 RULE *bindrule (const char *rulename) {
  50   RULE rule, *r = &rule;
  51   //
  52   if (!rulehash) rulehash = hashinit(sizeof(RULE), "rules");
  53   r->name = rulename;
  54   if (hashenter(rulehash, (HASHDATA **)&r)) {
  55     r->name = newstr(rulename); /* never freed */
  56     r->procedure = (PARSE *)0;
  57     r->actions = (char *)0;
  58     r->bindlist = L0;
  59     r->params = L0;
  60     r->flags = 0;
  61   }
  62   return r;
  63 }
  64
  65
  66 /*
  67  * bindtarget() - return pointer to TARGET, creating it if necessary
  68  */
  69 TARGET *bindtarget (const char *targetname) {
  70   TARGET target, *t = &target;
  71   //
  72   if (!targethash) targethash = hashinit(sizeof(TARGET), "targets");
  73   t->name = targetname;
  74   if (hashenter(targethash, (HASHDATA **)&t)) {
  75     memset((char *)t, '\0', sizeof(*t));
  76     t->name = newstr(targetname); /* never freed */
  77     t->boundname = t->name;   /* default for T_FLAG_NOTFILE */
  78   }
  79   return t;
  80 }
  81
  82
  83 /*
  84  * copytarget() - make a new target with the old target's name
  85  *
  86  * Not entered into hash table -- for internal nodes.
  87  */
  88 TARGET *copytarget (const TARGET *ot) {
  89   TARGET *t = (TARGET *)malloc(sizeof(*t));
  90   memset((char *)t, '\0', sizeof(*t));
  91   t->name = copystr(ot->name);
  92   t->boundname = t->name;
  93   t->flags |= T_FLAG_NOTFILE | T_FLAG_INTERNAL;
  94   return t;
  95 }
  96
  97
  98 /*
  99  * touchtarget() - mark a target to simulate being new
 100  */
 101 void touchtarget (const char *t) {
 102   bindtarget(t)->flags |= T_FLAG_TOUCHED;
 103 }
 104
 105
 106 /*
 107  * targetlist() - turn list of target names into a TARGET chain
 108  *
 109  * Inputs:
 110  *  chain existing TARGETS to append to
 111  *  targets list of target names
 112  */
 113 TARGETS *targetlist (TARGETS *chain, LIST *targets) {
 114   for (; targets; targets = list_next(targets)) chain = targetentry(chain, bindtarget(targets->string));
 115   return chain;
 116 }
 117
 118
 119 /*
 120  * targetentry() - add a TARGET to a chain of TARGETS
 121  *
 122  * Inputs:
 123  *  chain exisitng TARGETS to append to
 124  *  target  new target to append
 125  */
 126 TARGETS *targetentry (TARGETS *chain, TARGET *target) {
 127   TARGETS *c = (TARGETS *)malloc(sizeof(TARGETS));
 128   c->target = target;
 129   if (!chain) chain = c; else chain->tail->next = c;
 130   chain->tail = c;
 131   c->next = 0;
 132   return chain;
 133 }
 134
 135
 136 /*
 137  * targetchain() - append two TARGET chains
 138  *
 139  * Inputs:
 140  *  chain exisitng TARGETS to append to
 141  *  target  new target to append
 142  */
 143 TARGETS *targetchain (TARGETS *chain, TARGETS *targets) {
 144   if (!targets) return chain;
 145   if (!chain) return targets;
 146   chain->tail->next = targets;
 147   chain->tail = targets->tail;
 148   return chain;
 149 }
 150
 151
 152 /*
 153  * actionlist() - append to an ACTION chain
 154  */
 155 ACTIONS *actionlist (ACTIONS *chain, ACTION *action) {
 156   ACTIONS *actions = (ACTIONS *)malloc(sizeof(ACTIONS));
 157   actions->action = action;
 158   if (!chain) chain = actions; else chain->tail->next = actions;
 159   chain->tail = actions;
 160   actions->next = 0;
 161   return chain;
 162 }
 163
 164
 165 /*
 166  * addsettings() - add a deferred "set" command to a target
 167  *
 168  * Adds a variable setting (varname=list) onto a chain of settings
 169  * for a particular target.  Replaces the previous previous value,
 170  * if any, unless 'append' says to append the new list onto the old.
 171  * Returns the head of the chain of settings.
 172  */
 173 SETTINGS *addsettings (SETTINGS *head, int setflag, const char *symbol, LIST *value) {
 174   SETTINGS *v;
 175   /* look for previous setting */
 176   for (v = head; v; v = v->next) if (!strcmp(v->symbol, symbol)) break;
 177   /* if not previously set, alloc a new */
 178   /* if appending, do so */
 179   /* else free old and set new */
 180   if (!v) {
 181     v = (SETTINGS *)malloc(sizeof(*v));
 182     v->symbol = newstr(symbol);
 183     v->value = value;
 184     v->next = head;
 185     head = v;
 186   } else {
 187     switch (setflag) {
 188       case VAR_SET:
 189         /* toss old, set new */
 190         list_free(v->value);
 191         v->value = value;
 192         break;
 193       case VAR_APPEND:
 194         /* append new to old */
 195         v->value = list_append(v->value, value);
 196         break;
 197       case VAR_DEFAULT:
 198         /* toss new, old already set */
 199         list_free(value);
 200         break;
 201     }
 202   }
 203   /* return (new) head of list */
 204   return head;
 205 }
 206
 207
 208 /*
 209  * copysettings() - copy a settings list for temp use
 210  *
 211  * When target-specific variables are pushed into place with pushsettings(),
 212  * any global variables with the same name are swapped onto the target's
 213  * SETTINGS chain.  If that chain gets modified (by using the "on target"
 214  * syntax), popsettings() would wrongly swap those modified values back
 215  * as the new global values.
 216  *
 217  * copysettings() protects the target's SETTINGS chain by providing a
 218  * copy of the chain to pass to pushsettings() and popsettings(), so that
 219  * the target's original SETTINGS chain can be modified using the usual
 220  * "on target" syntax.
 221  */
 222 SETTINGS *copysettings (SETTINGS *from) {
 223   SETTINGS *head = 0;
 224   //
 225   for (; from; from = from->next) {
 226     SETTINGS *v = (SETTINGS *)malloc(sizeof(*v));
 227     v->symbol = copystr(from->symbol);
 228     v->value = list_copy(0, from->value);
 229     v->next = head;
 230     head = v;
 231   }
 232   return head;
 233 }
 234
 235
 236 /*
 237  * pushsettings() - set all target specific variables
 238  */
 239 void pushsettings (SETTINGS *v) {
 240   for (; v; v = v->next) v->value = var_swap(v->symbol, v->value);
 241 }
 242
 243
 244 /*
 245  * popsettings() - reset target specific variables to their pre-push values
 246  */
 247 void popsettings (SETTINGS *v) {
 248   pushsettings(v); /* just swap again */
 249 }
 250
 251
 252 /*
 253  *    freesettings() - delete a settings list
 254  */
 255 void freesettings (SETTINGS *v) {
 256   while (v) {
 257     SETTINGS *n = v->next;
 258     freestr(v->symbol);
 259     list_free(v->value);
 260     free((char *)v);
 261     v = n;
 262   }
 263 }
 264
 265
 266 /*
 267  * donerules() - free RULE and TARGET tables
 268  */
 269 void donerules (void) {
 270   hashdone(rulehash);
 271   hashdone(targethash);
 272 }