src/variable.c

   1 /*
   2  * Copyright 1993-2002 Christopher Seiwald and Perforce Software, Inc.
   3  *
   4  * This file is part of Jam - see jam.c for Copyright information.
   5  */
   6 /*
   7  * variable.c - handle jam multi-element variables
   8  *
   9  * External routines:
  10  *
  11  *  var_defines() - load a bunch of variable=value settings
  12  *  var_string() - expand a string with variables in it
  13  *  var_get() - get value of a user defined symbol
  14  *  var_set() - set a variable in jam's user defined symbol table
  15  *  var_swap() - swap a variable's value with the given one
  16  *  var_done() - free variable tables
  17  *
  18  * Internal routines:
  19  *
  20  *  var_enter() - make new var symbol table entry, returning var ptr
  21  *  var_dump() - dump a variable to stdout
  22  *
  23  * 04/13/94 (seiwald) - added shorthand L0 for null list pointer
  24  * 08/23/94 (seiwald) - Support for '+=' (append to variable)
  25  * 01/22/95 (seiwald) - split environment variables at blanks or :'s
  26  * 05/10/95 (seiwald) - split path variables at SPLITPATH (not :)
  27  * 09/11/00 (seiwald) - defunct var_list() removed
  28  * 10/22/02 (seiwald) - list_new() now does its own newstr()/copystr()
  29  * 11/04/02 (seiwald) - const-ing for string literals
  30  */
  31 #include "jam.h"
  32 #include "lists.h"
  33 #include "parse.h"
  34 #include "variable.h"
  35 #include "expand.h"
  36 #include "hash.h"
  37 #include "newstr.h"
  38
  39
  40 static struct hash *varhash = NULL;
  41
  42
  43 /*
  44  * VARIABLE - a user defined multi-value variable
  45  */
  46
  47 typedef struct _variable VARIABLE;
  48 struct _variable {
  49   const char *symbol;
  50   LIST *value;
  51 };
  52
  53
  54 /*
  55  * var_dump() - dump a variable to stdout
  56  */
  57 static void var_dump (const char *symbol, LIST *value, const char *what) {
  58   printf("%s %s = ", what, symbol);
  59   list_print(value);
  60   printf("\n");
  61 }
  62
  63
  64 /*
  65  * var_enter() - make new var symbol table entry, returning var ptr
  66  */
  67 static VARIABLE *var_enter (const char *symbol) {
  68   VARIABLE var, *v = &var;
  69   //
  70   if (!varhash) varhash = hashinit(sizeof(VARIABLE), "variables");
  71   v->symbol = symbol;
  72   v->value = 0;
  73   if (hashenter(varhash, (HASHDATA **)&v)) v->symbol = newstr(symbol); /* never freed */
  74   return v;
  75 }
  76
  77
  78 /*
  79  * var_defines()
  80  */
  81 void var_defines (const char **e) {
  82   for (; *e; ++e) {
  83     const char *val;
  84     /* just say "no": windows defines this in the env, but we don't want it to override our notion of OS */
  85     if (!strcmp(*e, "OS=Windows_NT")) continue;
  86    /* Just say "no": on Unix, variables can contain function
  87     * definitions. their value begins with "()"
  88     */
  89     if ((val = strchr(*e, '=')) && val[1] == '(' && val[2] == ')') continue;
  90     if ((val = strchr(*e, '='))) {
  91       LIST *l = L0;
  92       const char *pp, *p;
  93       char split = ' ';
  94       char buf[MAXSYM];
  95       /* split *PATH at :'s, not spaces */
  96       if (val-4 >= *e) {
  97         if (!strncmp(val-4, "PATH", 4) || !strncmp(val-4, "Path", 4) || !strncmp(val-4, "path", 4)) split = SPLITPATH;
  98       }
  99       /* do the split */
 100       for (pp = val+1; (p = strchr(pp, split)); pp = p+1) {
 101         int len = p-pp;
 102         //
 103         if (len >= sizeof(buf)) len = sizeof(buf)-1;
 104         strncpy(buf, pp, len);
 105         buf[len] = '\0';
 106         l = list_new(l, buf, 0);
 107       }
 108       l = list_new(l, pp, 0);
 109       /* get name */
 110       strncpy(buf, *e, val-*e);
 111       buf[val-*e] = '\0';
 112       var_set(buf, l, VAR_SET);
 113     }
 114   }
 115 }
 116
 117
 118 /*
 119  * var_string()
 120  */
 121 int var_string (const char *in, tKString *out, LOL *lol, char separator) {
 122   int osz = kStringLen(out), lwpos;
 123   const char *st;
 124   //
 125   while (*in) {
 126     //char *lastword;
 127     int dollar = 0;
 128     /* copy white space */
 129     st = in;
 130     while (isspace(*in)) ++in;
 131     kStringAppendRange(out, st, in);
 132     //
 133     lwpos = kStringLen(out);
 134     /* copy non-white space, watching for variables */
 135     st = in;
 136     while (*in && !isspace(*in)) {
 137       if (in[0] == '$' && in[1] == '(') ++dollar;
 138       ++in;
 139     }
 140     kStringAppendRange(out, st, in);
 141     /* if a variable encountered, expand it and and embed the space-separated members of the list in the output */
 142     if (dollar) {
 143       LIST *l = var_expand(L0, kStringCStr(out)+lwpos, kStringCStr(out)+kStringLen(out), lol, 0), *hd = l;
 144       kStringTruncate(out, lwpos);
 145       while (l != NULL) {
 146         kStringAppendCStr(out, l->string);
 147         /* separate with space */
 148         if ((l = list_next(l)) != NULL) kStringPushBack(out, separator);
 149       }
 150       list_free(hd);
 151     }
 152   }
 153   return kStringLen(out)-osz;
 154 }
 155
 156
 157 /*
 158  * var_get()
 159  */
 160 LIST *var_get (const char *symbol) {
 161   VARIABLE var, *v = &var;
 162   //
 163   v->symbol = symbol;
 164   if (varhash && hashcheck(varhash, (HASHDATA **)&v)) {
 165     if (DEBUG_VARGET) var_dump(v->symbol, v->value, "get");
 166     return v->value;
 167   }
 168   return 0;
 169 }
 170
 171
 172 /*
 173  * var_set()
 174  */
 175 void var_set (const char *symbol, LIST *value, int flag) {
 176   VARIABLE *v = var_enter(symbol);
 177   //
 178   if (DEBUG_VARSET) var_dump(symbol, value, "set");
 179   switch(flag) {
 180     case VAR_SET:
 181       /* Replace value */
 182       list_free(v->value);
 183       v->value = value;
 184       break;
 185     case VAR_APPEND:
 186       /* Append value */
 187       v->value = list_append(v->value, value);
 188       break;
 189     case VAR_REMOVE:
 190       /* Remove all values */
 191       v->value = list_removeall(v->value, value);
 192       list_free(value);
 193       break;
 194     case VAR_DEFAULT:
 195       /* Set only if unset */
 196       if (!v->value) v->value = value; else list_free(value);
 197       break;
 198   }
 199 }
 200
 201
 202 /*
 203  * var_swap()
 204  */
 205 LIST *var_swap (const char *symbol, LIST *value) {
 206   VARIABLE *v = var_enter(symbol);
 207   LIST *oldvalue = v->value;
 208   //
 209   if (DEBUG_VARSET) var_dump(symbol, value, "set");
 210   v->value = value;
 211   return oldvalue;
 212 }
 213
 214
 215 /*
 216  * var_done()
 217  */
 218 void var_done (void) {
 219   hashdone(varhash);
 220 }