gcc/prefix.c

   1 /* Utility to update paths from internal to external forms.
   2    Copyright (C) 1997, 1998, 1999, 2000 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 '$') and further translation will be done as follows
  38    until none of the two conditions below are met:
  39
  40    1) If the filename begins with '@', the string between the '@' and
  41    the end of the name or the first '/' or directory separator will
  42    be considered a "key" and looked up as follows:
  43
  44    -- If this is a Win32 OS, then the Registry will be examined for
  45       an entry of "key" in
  46
  47       HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<KEY>
  48
  49       if found, that value will be used. <KEY> defaults to GCC version
  50       string, but can be overridden at configuration time.
  51
  52    -- If not found (or not a Win32 OS), the environment variable
  53       key_ROOT (the value of "key" concatenated with the constant "_ROOT")
  54       is tried.  If that fails, then PREFIX (see above) is used.
  55
  56    2) If the filename begins with a '$', the rest of the string up
  57    to the end or the first '/' or directory separator will be used
  58    as an environment variable, whose value will be returned.
  59
  60    Once all this is done, any '/' will be converted to DIR_SEPARATOR,
  61    if they are different.
  62
  63    NOTE:  using resolve_keyed_path under Win32 requires linking with
  64    advapi32.dll.  */
  65
  66
  67 #include "config.h"
  68 #include "system.h"
  69 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
  70 #include <windows.h>
  71 #endif
  72 #include "prefix.h"
  73
  74 static const char *std_prefix = PREFIX;
  75
  76 static const char *get_key_value        PARAMS ((char *));
  77 static const char *translate_name       PARAMS ((const char *));
  78 static char *save_string                PARAMS ((const char *, int));
  79
  80 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
  81 static char *lookup_key         PARAMS ((char *));
  82 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE;
  83 #endif
  84
  85 /* Given KEY, as above, return its value.  */
  86
  87 static const char *
  88 get_key_value (key)
  89      char *key;
  90 {
  91   const char *prefix = 0;
  92   char *temp = 0;
  93
  94 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
  95   prefix = lookup_key (key);
  96 #endif
  97
  98   if (prefix == 0)
  99     prefix = getenv (temp = concat (key, "_ROOT", NULL_PTR));
 100
 101   if (prefix == 0)
 102     prefix = std_prefix;
 103
 104   if (temp)
 105     free (temp);
 106
 107   return prefix;
 108 }
 109
 110 /* Concatenate a sequence of strings, returning the result.
 111
 112    This function is based on the one in libiberty.  */
 113
 114 char *
 115 concat VPARAMS ((const char *first, ...))
 116 {
 117   register int length;
 118   register char *newstr;
 119   register char *end;
 120   register const char *arg;
 121   va_list args;
 122 #ifndef ANSI_PROTOTYPES
 123   const char *first;
 124 #endif
 125
 126   /* First compute the size of the result and get sufficient memory.  */
 127
 128   VA_START (args, first);
 129 #ifndef ANSI_PROTOTYPES
 130   first = va_arg (args, const char *);
 131 #endif
 132
 133   arg = first;
 134   length = 0;
 135
 136   while (arg != 0)
 137     {
 138       length += strlen (arg);
 139       arg = va_arg (args, const char *);
 140     }
 141
 142   newstr = (char *) xmalloc (length + 1);
 143   va_end (args);
 144
 145   /* Now copy the individual pieces to the result string.  */
 146
 147   VA_START (args, first);
 148 #ifndef ANSI_PROTOTYPES
 149   first = va_arg (args, char *);
 150 #endif
 151
 152   end = newstr;
 153   arg = first;
 154   while (arg != 0)
 155     {
 156       while (*arg)
 157         *end++ = *arg++;
 158       arg = va_arg (args, const char *);
 159     }
 160   *end = '\000';
 161   va_end (args);
 162
 163   return (newstr);
 164 }
 165
 166 /* Return a copy of a string that has been placed in the heap.  */
 167
 168 static char *
 169 save_string (s, len)
 170   const char *s;
 171   int len;
 172 {
 173   register char *result = xmalloc (len + 1);
 174
 175   bcopy (s, result, len);
 176   result[len] = 0;
 177   return result;
 178 }
 179
 180 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
 181
 182 /* Look up "key" in the registry, as above.  */
 183
 184 static char *
 185 lookup_key (key)
 186      char *key;
 187 {
 188   char *dst;
 189   DWORD size;
 190   DWORD type;
 191   LONG res;
 192
 193   if (reg_key == (HKEY) INVALID_HANDLE_VALUE)
 194     {
 195       res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0,
 196                            KEY_READ, &reg_key);
 197
 198       if (res == ERROR_SUCCESS)
 199         res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0,
 200                              KEY_READ, &reg_key);
 201
 202       if (res == ERROR_SUCCESS)
 203         res = RegOpenKeyExA (reg_key, WIN32_REGISTRY_KEY, 0,
 204                              KEY_READ, &reg_key);
 205
 206       if (res != ERROR_SUCCESS)
 207         {
 208           reg_key = (HKEY) INVALID_HANDLE_VALUE;
 209           return 0;
 210         }
 211     }
 212
 213   size = 32;
 214   dst = (char *) xmalloc (size);
 215
 216   res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 217   if (res == ERROR_MORE_DATA && type == REG_SZ)
 218     {
 219       dst = (char *) xrealloc (dst, size);
 220       res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 221     }
 222
 223   if (type != REG_SZ || res != ERROR_SUCCESS)
 224     {
 225       free (dst);
 226       dst = 0;
 227     }
 228
 229   return dst;
 230 }
 231 #endif
 232
 233 /* If NAME starts with a '@' or '$', apply the translation rules above
 234    and return a new name.  Otherwise, return the given name.  */
 235
 236 static const char *
 237 translate_name (name)
 238   const char *name;
 239 {
 240   char code = name[0];
 241   char *key;
 242   const char *prefix = 0;
 243   int keylen;
 244
 245   if (code != '@' && code != '$')
 246     return name;
 247
 248   for (keylen = 0;
 249        (name[keylen + 1] != 0 && !IS_DIR_SEPARATOR (name[keylen + 1]));
 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   /* We used to strip trailing DIR_SEPARATORs here, but that can
 272      sometimes yield a result with no separator when one was coded
 273      and intended by the user, causing two path components to run
 274      together.  */
 275
 276   return concat (prefix, name, NULL_PTR);
 277 }
 278
 279 /* Update PATH using KEY if PATH starts with PREFIX.  */
 280
 281 const char *
 282 update_path (path, key)
 283   const char *path;
 284   const char *key;
 285 {
 286   if (! strncmp (path, std_prefix, strlen (std_prefix)) && key != 0)
 287     {
 288       if (key[0] != '$')
 289         key = concat ("@", key, NULL_PTR);
 290
 291       path = concat (key, &path[strlen (std_prefix)], NULL_PTR);
 292
 293       while (path[0] == '@' || path[0] == '$')
 294         path = translate_name (path);
 295     }
 296
 297 #ifdef UPDATE_PATH_HOST_CANONICALIZE
 298 /* Perform host dependant canonicalization when needed.  */
 299 UPDATE_PATH_HOST_CANONICALIZE (path, key);
 300 #endif
 301
 302 #ifdef DIR_SEPARATOR_2
 303   /* Convert DIR_SEPARATOR_2 to DIR_SEPARATOR. */
 304   if (DIR_SEPARATOR != DIR_SEPARATOR_2)
 305     {
 306       char *new_path = xstrdup (path);
 307       path = new_path;
 308       do {
 309         if (*new_path == DIR_SEPARATOR_2)
 310           *new_path = DIR_SEPARATOR;
 311       } while (*new_path++);
 312     }
 313 #endif
 314
 315 #if defined (DIR_SEPARATOR) && !defined (DIR_SEPARATOR_2)
 316   if (DIR_SEPARATOR != '/')
 317     {
 318       char *new_path = xstrdup (path);
 319       path = new_path;
 320       do {
 321         if (*new_path == '/')
 322           *new_path = DIR_SEPARATOR;
 323       } while (*new_path++);
 324     }
 325 #endif
 326
 327   return path;
 328 }
 329
 330 /* Reset the standard prefix */
 331 void
 332 set_std_prefix (prefix, len)
 333   const char *prefix;
 334   int len;
 335 {
 336   std_prefix = save_string (prefix, len);
 337 }