gcc/prefix.c

   1 /* Utility to update paths from internal to external forms.
   2    Copyright (C) 1997 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 #ifdef __STDC__
  68 #include <stdarg.h>
  69 #else
  70 #include <varargs.h>
  71 #endif
  72 #include "system.h"
  73 #ifdef _WIN32
  74 #include <windows.h>
  75 #endif
  76
  77 #include "gansidecl.h"
  78
  79 static char *get_key_value      PROTO((char *));
  80 static char *translate_name     PROTO((char *));
  81 static char *concat             PVPROTO((char *, ...));
  82 static char *save_string        PROTO((char *, int));
  83
  84 #ifdef _WIN32
  85 static char *lookup_key         PROTO((char *));
  86 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE;
  87 #endif
  88
  89 /* Given KEY, as above, return its value.  */
  90
  91 static char *
  92 get_key_value (key)
  93      char *key;
  94 {
  95   char *prefix = 0;
  96
  97 #ifdef _WIN32
  98   prefix = lookup_key (key);
  99 #endif
 100
 101   if (prefix == 0)
 102     prefix = getenv (concat (key, "_ROOT", NULL_PTR));
 103
 104   if (prefix == 0)
 105     prefix = PREFIX;
 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 static char *
 115 concat VPROTO((char *first, ...))
 116 {
 117   register int length;
 118   register char *newstr;
 119   register char *end;
 120   register char *arg;
 121   va_list args;
 122 #ifndef __STDC__
 123   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 __STDC__
 130   first = va_arg (args, 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, char *);
 140     }
 141
 142   newstr = (char *) malloc (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 __STDC__
 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, 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      char *s;
 171      int len;
 172 {
 173   register char *result = (char *) malloc (len + 1);
 174
 175   bcopy (s, result, len);
 176   result[len] = 0;
 177   return result;
 178 }
 179
 180 #ifdef _WIN32
 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         {
 204           reg_key = (HKEY) INVALID_HANDLE_VALUE;
 205           return 0;
 206         }
 207     }
 208
 209   size = 32;
 210   dst = (char *) malloc (size);
 211
 212   res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 213   if (res == ERROR_MORE_DATA && type == REG_SZ)
 214     {
 215       dst = (char *) realloc (dst, size);
 216       res = RegQueryValueExA (reg_key, key, 0, &type, dst, &size);
 217     }
 218
 219   if (type != REG_SZ || res != ERROR_SUCCESS)
 220     {
 221       free (dst);
 222       dst = 0;
 223     }
 224
 225   return dst;
 226 }
 227 #endif
 228
 229 /* If NAME starts with a '@' or '$', apply the translation rules above
 230    and return a new name.  Otherwise, return the given name.  */
 231
 232 static char *
 233 translate_name (name)
 234      char *name;
 235 {
 236   char code = name[0];
 237   char *key, *prefix;
 238   int keylen;
 239
 240   if (code != '@' && code != '$')
 241     return name;
 242
 243   for (keylen = 0;
 244        (name[keylen + 1] != 0 && name[keylen + 1] != '/'
 245 #ifdef DIR_SEPARATOR
 246         && name[keylen + 1] != DIR_SEPARATOR
 247 #endif
 248         );
 249        keylen++)
 250     ;
 251
 252   key = alloca (keylen + 1);
 253   strncpy (key, &name[1], keylen);
 254   key[keylen] = 0;
 255
 256   name = &name[keylen + 1];
 257
 258   if (code == '@')
 259     {
 260       prefix = get_key_value (key);
 261       if (prefix == 0)
 262         prefix = PREFIX;
 263     }
 264   else
 265     {
 266       prefix = getenv (key);
 267       if (prefix == 0)
 268         prefix = concat ("$", key, NULL_PTR);
 269     }
 270
 271   /* Remove any trailing directory separator from what we got.  */
 272   if (prefix[strlen (prefix) - 1] == '/'
 273 #ifdef DIR_SEPARATOR
 274       || prefix[strlen (prefix) - 1] == DIR_SEPARATOR
 275 #endif
 276       )
 277     {
 278       prefix = save_string (prefix, strlen (prefix));
 279       prefix[strlen (prefix) - 1] = 0;
 280     }
 281
 282   return concat (prefix, name, NULL_PTR);
 283 }
 284
 285 /* Update PATH using KEY if PATH starts with PREFIX.  */
 286
 287 char *
 288 update_path (path, key)
 289      char *path;
 290      char *key;
 291 {
 292   if (! strncmp (path, PREFIX, strlen (PREFIX)) && key != 0)
 293     {
 294       if (key[0] != '$')
 295         key = concat ("@", key, NULL_PTR);
 296
 297       path = concat (key, &path[strlen (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 }