gcc/prefix.c

   1 /* Utility to update paths from internal to external forms.
   2    Copyright (C) 1997, 1998 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU Library General Public
   8 License as published by the Free Software Foundation; either
   9 version 2 of the License, or (at your option) any later version.
  10
  11 GCC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 Library General Public License for more details.
  15
  16 You should have received a copy of the GNU Library General Public
  17 License along with GCC; see the file COPYING.  If not, write to the Free
  18 Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* This file contains routines to update a path, both to canonicalize
  22    the directory format and to handle any prefix translation.
  23
  24    This file must be compiled with -DPREFIX= to specify the "prefix"
  25    value used by configure.  If a filename does not begin with this
  26    prefix, it will not be affected other than by directory canonicalization.
  27
  28    Each caller of 'update_path' may specify both a filename and
  29    a translation prefix and consist of the name of the package that contains
  30    the file ("@GCC", "@BINUTIL", "@GNU", etc).
  31
  32    If the prefix is not specified, the filename will only undergo
  33    directory canonicalization.
  34
  35    If it is specified, the string given by PREFIX will be replaced
  36    by the specified prefix (with a '@' in front unless the prefix begins
  37    with a '$') and further translation will be done as follows
  38    until none of the two conditions below are met:
  39
  40    1) If the filename begins with '@', the string between the '@' and
  41    the end of the name or the first '/' or directory separator will
  42    be considered a "key" and looked up as follows:
  43
  44    -- If this is a Win32 OS, then the Registry will be examined for
  45       an entry of "key" in
  46
  47       HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\
  48
  49       if found, that value will be used.
  50
  51    -- If not found (or not a Win32 OS), the environment variable
  52       key_ROOT (the value of "key" concatenated with the constant "_ROOT")
  53       is tried.  If that fails, then PREFIX (see above) is used.
  54
  55    2) If the filename begins with a '$', the rest of the string up
  56    to the end or the first '/' or directory separator will be used
  57    as an environment variable, whose value will be returned.
  58
  59    Once all this is done, any '/' will be converted to DIR_SEPARATOR,
  60    if they are different.
  61
  62    NOTE:  using resolve_keyed_path under Win32 requires linking with
  63    advapi32.dll.  */
  64
  65
  66 #include "config.h"
  67 #include "system.h"
  68 #ifdef _WIN32
  69 #include <windows.h>
  70 #endif
  71
  72 #include "gansidecl.h"
  73
  74 static char *std_prefix = PREFIX;
  75
  76 static char *get_key_value      PROTO((char *));
  77 static char *translate_name     PROTO((char *));
  78 static char *concat             PVPROTO((char *, ...));
  79 static char *save_string        PROTO((char *, int));
  80
  81 #ifdef _WIN32
  82 static char *lookup_key         PROTO((char *));
  83 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE;
  84 #endif
  85
  86 /* Given KEY, as above, return its value.  */
  87
  88 static char *
  89 get_key_value (key)
  90      char *key;
  91 {
  92   char *prefix = 0;
  93   char *temp = 0;
  94
  95 #ifdef _WIN32
  96   prefix = lookup_key (key);
  97 #endif
  98
  99   if (prefix == 0)
 100     prefix = getenv (temp = concat (key, "_ROOT", NULL_PTR));
 101
 102   if (prefix == 0)
 103     prefix = std_prefix;
 104
 105   if (temp)
 106     free (temp);
 107
 108   return prefix;
 109 }
 110
 111 /* Concatenate a sequence of strings, returning the result.
 112
 113    This function is based on the one in libiberty.  */
 114
 115 static char *
 116 concat VPROTO((char *first, ...))
 117 {
 118   register int length;
 119   register char *newstr;
 120   register char *end;
 121   register char *arg;
 122   va_list args;
 123 #ifndef __STDC__
 124   char *first;
 125 #endif
 126
 127   /* First compute the size of the result and get sufficient memory.  */
 128
 129   VA_START (args, first);
 130 #ifndef __STDC__
 131   first = va_arg (args, char *);
 132 #endif
 133
 134   arg = first;
 135   length = 0;
 136
 137   while (arg != 0)
 138     {
 139       length += strlen (arg);
 140       arg = va_arg (args, char *);
 141     }
 142
 143   newstr = (char *) malloc (length + 1);
 144   va_end (args);
 145
 146   /* Now copy the individual pieces to the result string.  */
 147
 148   VA_START (args, first);
 149 #ifndef __STDC__
 150   first = va_arg (args, char *);
 151 #endif
 152
 153   end = newstr;
 154   arg = first;
 155   while (arg != 0)
 156     {
 157       while (*arg)
 158         *end++ = *arg++;
 159       arg = va_arg (args, char *);
 160     }
 161   *end = '\000';
 162   va_end (args);
 163
 164   return (newstr);
 165 }
 166
 167 /* Return a copy of a string that has been placed in the heap.  */
 168
 169 static char *
 170 save_string (s, len)
 171      char *s;
 172      int len;
 173 {
 174   register char *result = (char *) malloc (len + 1);
 175
 176   bcopy (s, result, len);
 177   result[len] = 0;
 178   return result;
 179 }
 180
 181 #ifdef _WIN32
 182
 183 /* Look up "key" in the registry, as above.  */
 184
 185 static char *
 186 lookup_key (key)
 187      char *key;
 188 {
 189   char *dst;
 190   DWORD size;
 191   DWORD type;
 192   LONG res;
 193
 194   if (reg_key == (HKEY) INVALID_HANDLE_VALUE)
 195     {
 196       res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0,
 197                            KEY_READ, &reg_key);
 198
 199       if (res == ERROR_SUCCESS)
 200         res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0,
 201                              KEY_READ, &reg_key);
 202
 203       if (res != ERROR_SUCCESS)
 204         {
 205           reg_key = (HKEY) INVALID_HANDLE_VALUE;
 206           return 0;
 207         }
 208     }
 209
 210   size = 32;
 211   dst = (char *) malloc (size);
 212
 213   res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 214   if (res == ERROR_MORE_DATA && type == REG_SZ)
 215     {
 216       dst = (char *) realloc (dst, size);
 217       res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 218     }
 219
 220   if (type != REG_SZ || res != ERROR_SUCCESS)
 221     {
 222       free (dst);
 223       dst = 0;
 224     }
 225
 226   return dst;
 227 }
 228 #endif
 229
 230 /* If NAME starts with a '@' or '$', apply the translation rules above
 231    and return a new name.  Otherwise, return the given name.  */
 232
 233 static char *
 234 translate_name (name)
 235      char *name;
 236 {
 237   char code = name[0];
 238   char *key, *prefix = 0;
 239   int keylen;
 240
 241   if (code != '@' && code != '$')
 242     return name;
 243
 244   for (keylen = 0;
 245        (name[keylen + 1] != 0 && name[keylen + 1] != '/'
 246 #ifdef DIR_SEPARATOR
 247         && name[keylen + 1] != DIR_SEPARATOR
 248 #endif
 249         );
 250        keylen++)
 251     ;
 252
 253   key = (char *) alloca (keylen + 1);
 254   strncpy (key, &name[1], keylen);
 255   key[keylen] = 0;
 256
 257   name = &name[keylen + 1];
 258
 259   if (code == '@')
 260     {
 261       prefix = get_key_value (key);
 262       if (prefix == 0)
 263         prefix = std_prefix;
 264     }
 265   else
 266     prefix = getenv (key);
 267
 268   if (prefix == 0)
 269     prefix = PREFIX;
 270
 271   /* Remove any trailing directory separator from what we got.  */
 272   if (prefix[strlen (prefix) - 1] == '/'
 273 #ifdef DIR_SEPARATOR
 274       || prefix[strlen (prefix) - 1] == DIR_SEPARATOR
 275 #endif
 276       )
 277     {
 278       prefix = save_string (prefix, strlen (prefix));
 279       prefix[strlen (prefix) - 1] = 0;
 280     }
 281
 282   return concat (prefix, name, NULL_PTR);
 283 }
 284
 285 /* Update PATH using KEY if PATH starts with PREFIX.  */
 286
 287 char *
 288 update_path (path, key)
 289      char *path;
 290      char *key;
 291 {
 292   if (! strncmp (path, std_prefix, strlen (std_prefix)) && key != 0)
 293     {
 294       if (key[0] != '$')
 295         key = concat ("@", key, NULL_PTR);
 296
 297       path = concat (key, &path[strlen (std_prefix)], NULL_PTR);
 298
 299       while (path[0] == '@' || path[0] == '$')
 300         path = translate_name (path);
 301     }
 302
 303 #ifdef DIR_SEPARATOR
 304   if (DIR_SEPARATOR != '/')
 305     {
 306       int i;
 307       int len = strlen (path);
 308
 309       path = save_string (path, len);
 310       for (i = 0; i < len; i++)
 311         if (path[i] == '/')
 312           path[i] = DIR_SEPARATOR;
 313     }
 314 #endif
 315
 316   return path;
 317 }
 318
 319 /* Reset the standard prefix */
 320 void
 321 set_std_prefix (prefix, len)
 322      char *prefix;
 323      int len;
 324 {
 325   std_prefix = save_string (prefix, len);
 326 }