sdcc/support/cpp/gcc/prefix.cc

   1 /* Utility to update paths from internal to external forms.
   2    Copyright (C) 1997-2022 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU Library General Public License as published by
   8 the Free Software Foundation; either version 3 of the License, or (at
   9 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 COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* This file contains routines to update a path, both to canonicalize
  21    the directory format and to handle any prefix translation.
  22
  23    This file must be compiled with -DPREFIX= to specify the "prefix"
  24    value used by configure.  If a filename does not begin with this
  25    prefix, it will not be affected other than by directory canonicalization.
  26
  27    Each caller of 'update_path' may specify both a filename and
  28    a translation prefix and consist of the name of the package that contains
  29    the file ("@GCC", "@BINUTIL", "@GNU", etc).
  30
  31    If the prefix is not specified, the filename will only undergo
  32    directory canonicalization.
  33
  34    If it is specified, the string given by PREFIX will be replaced
  35    by the specified prefix (with a '@' in front unless the prefix begins
  36    with a '$') and further translation will be done as follows
  37    until none of the two conditions below are met:
  38
  39    1) If the filename begins with '@', the string between the '@' and
  40    the end of the name or the first '/' or directory separator will
  41    be considered a "key" and looked up as follows:
  42
  43    -- If this is a Win32 OS, then the Registry will be examined for
  44       an entry of "key" in
  45
  46       HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<KEY>
  47
  48       if found, that value will be used. <KEY> defaults to GCC version
  49       string, but can be overridden at configuration time.
  50
  51    -- If not found (or not a Win32 OS), the environment variable
  52       key_ROOT (the value of "key" concatenated with the constant "_ROOT")
  53       is tried.  If that fails, then PREFIX (see above) is used.
  54
  55    2) If the filename begins with a '$', 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
  67 #include "config.h"
  68 #include "system.h"
  69 #include "coretypes.h"
  70 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
  71 #define WIN32_LEAN_AND_MEAN
  72 #include <windows.h>
  73 #endif
  74 #include "prefix.h"
  75 #include "common/common-target.h"
  76
  77 #define untested() { fprintf (stderr, "@@#\n@@@:%s:%d:%s\n", __FILE__, __LINE__, __func__); }
  78
  79 static const char *std_prefix = PREFIX;
  80
  81 static const char *get_key_value (char *);
  82 static char *translate_name (char *);
  83 static char *save_string (const char *, int);
  84 static void tr (char *, int, int);
  85
  86 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
  87 static char *lookup_key (char *);
  88 static HKEY reg_key = (HKEY) INVALID_HANDLE_VALUE;
  89 #endif
  90
  91 /* Given KEY, as above, return its value.  */
  92
  93 static const char *
  94 get_key_value (char *key)
  95 {
  96   const char *prefix = 0;
  97   char *temp = 0;
  98
  99 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
 100   prefix = lookup_key (key);
 101 #endif
 102
 103   if (prefix == 0)
 104     prefix = getenv (temp = concat (key, "_ROOT", NULL));
 105
 106   if (prefix == 0)
 107     prefix = std_prefix;
 108
 109   free (temp);
 110
 111   return prefix;
 112 }
 113
 114 /* Return a copy of a string that has been placed in the heap.  */
 115
 116 static char *
 117 save_string (const char *s, int len)
 118 {
 119   char *result = XNEWVEC (char, len + 1);
 120
 121   memcpy (result, s, len);
 122   result[len] = 0;
 123   return result;
 124 }
 125
 126 #if defined(_WIN32) && defined(ENABLE_WIN32_REGISTRY)
 127
 128 #ifndef WIN32_REGISTRY_KEY
 129 # define WIN32_REGISTRY_KEY BASEVER
 130 #endif
 131
 132 /* Look up "key" in the registry, as above.  */
 133
 134 static char *
 135 lookup_key (char *key)
 136 {
 137   char *dst;
 138   DWORD size;
 139   DWORD type;
 140   LONG res;
 141
 142   if (reg_key == (HKEY) INVALID_HANDLE_VALUE)
 143     {
 144       res = RegOpenKeyExA (HKEY_LOCAL_MACHINE, "SOFTWARE", 0,
 145                            KEY_READ, &reg_key);
 146
 147       if (res == ERROR_SUCCESS)
 148         res = RegOpenKeyExA (reg_key, "Free Software Foundation", 0,
 149                              KEY_READ, &reg_key);
 150
 151       if (res == ERROR_SUCCESS)
 152         res = RegOpenKeyExA (reg_key, WIN32_REGISTRY_KEY, 0,
 153                              KEY_READ, &reg_key);
 154
 155       if (res != ERROR_SUCCESS)
 156         {
 157           reg_key = (HKEY) INVALID_HANDLE_VALUE;
 158           return 0;
 159         }
 160     }
 161
 162   size = 32;
 163   dst = XNEWVEC (char, size);
 164
 165   res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size);
 166   if (res == ERROR_MORE_DATA && type == REG_SZ)
 167     {
 168       dst = XRESIZEVEC (char, dst, size);
 169       res = RegQueryValueExA (reg_key, key, 0, &type, (LPBYTE) dst, &size);
 170     }
 171
 172   if (type != REG_SZ || res != ERROR_SUCCESS)
 173     {
 174       free (dst);
 175       dst = 0;
 176     }
 177
 178   return dst;
 179 }
 180 #endif
 181
 182 /* If NAME, a malloc-ed string, starts with a '@' or '$', apply the
 183    translation rules above and return a newly malloc-ed name.
 184    Otherwise, return the given name.  */
 185
 186 static char *
 187 translate_name (char *name)
 188 {
 189   char code;
 190   char *key, *old_name;
 191   const char *prefix;
 192   int keylen;
 193
 194   for (;;)
 195     {
 196       code = name[0];
 197       if (code != '@' && code != '$')
 198         break;
 199
 200       for (keylen = 0;
 201            (name[keylen + 1] != 0 && !IS_DIR_SEPARATOR (name[keylen + 1]));
 202            keylen++)
 203         ;
 204
 205       key = (char *) alloca (keylen + 1);
 206       memcpy (key, &name[1], keylen);
 207       key[keylen] = 0;
 208
 209       if (code == '@')
 210         {
 211           prefix = get_key_value (key);
 212           if (prefix == 0)
 213             prefix = std_prefix;
 214         }
 215       else
 216         prefix = getenv (key);
 217
 218       if (prefix == 0)
 219         prefix = PREFIX;
 220
 221       /* We used to strip trailing DIR_SEPARATORs here, but that can
 222          sometimes yield a result with no separator when one was coded
 223          and intended by the user, causing two path components to run
 224          together.  */
 225
 226       old_name = name;
 227       name = concat (prefix, &name[keylen + 1], NULL);
 228       free (old_name);
 229     }
 230
 231   return name;
 232 }
 233
 234 /* In a NUL-terminated STRING, replace character C1 with C2 in-place.  */
 235 static void
 236 tr (char *string, int c1, int c2)
 237 {
 238   do
 239     {
 240       if (*string == c1)
 241         *string = c2;
 242     }
 243   while (*string++);
 244 }
 245
 246 /* Update PATH using KEY if PATH starts with PREFIX as a directory.
 247    The returned string is always malloc-ed, and the caller is
 248    responsible for freeing it.  */
 249
 250 char *
 251 update_path (const char *path, const char *key)
 252 {
 253   char *result, *p;
 254   const int len = strlen (std_prefix);
 255
 256   if (! filename_ncmp (path, std_prefix, len)
 257       && (IS_DIR_SEPARATOR (path[len])
 258           || path[len] == '\0')
 259       && key != 0)
 260     {
 261       bool free_key = false;
 262
 263       if (key[0] != '$')
 264         {
 265           key = concat ("@", key, NULL);
 266           free_key = true;
 267         }
 268
 269       result = concat (key, &path[len], NULL);
 270       if (free_key)
 271         free (CONST_CAST (char *, key));
 272       result = translate_name (result);
 273     }
 274   else
 275     result = xstrdup (path);
 276
 277   p = result;
 278   while (1)
 279     {
 280       char *src, *dest;
 281
 282       p = strchr (p, '.');
 283       if (p == NULL)
 284         break;
 285       /* Look for `/../'  */
 286       if (p[1] == '.'
 287           && IS_DIR_SEPARATOR (p[2])
 288           && (p != result && IS_DIR_SEPARATOR (p[-1])))
 289         {
 290           *p = 0;
 291           if (1 // sdcpp !targetm_common.always_strip_dotdot
 292               && access (result, X_OK) == 0)
 293             {
 294               *p = '.';
 295               break;
 296             }
 297           else
 298             {
 299               /* We can't access the dir, so we won't be able to
 300                  access dir/.. either.  Strip out `dir/../'.  If `dir'
 301                  turns out to be `.', strip one more path component.  */
 302               dest = p;
 303               do
 304                 {
 305                   --dest;
 306                   while (dest != result && IS_DIR_SEPARATOR (*dest))
 307                     --dest;
 308                   while (dest != result && !IS_DIR_SEPARATOR (dest[-1]))
 309                     --dest;
 310                 }
 311               while (dest != result && *dest == '.');
 312               /* If we have something like `./..' or `/..', don't
 313                  strip anything more.  */
 314               if (*dest == '.' || IS_DIR_SEPARATOR (*dest))
 315                 {
 316                   *p = '.';
 317                   break;
 318                 }
 319               src = p + 3;
 320               while (IS_DIR_SEPARATOR (*src))
 321                 ++src;
 322               p = dest;
 323               while ((*dest++ = *src++) != 0)
 324                 ;
 325             }
 326         }
 327       else
 328         ++p;
 329     }
 330
 331 #ifdef UPDATE_PATH_HOST_CANONICALIZE
 332   /* Perform host dependent canonicalization when needed.  */
 333   UPDATE_PATH_HOST_CANONICALIZE (result);
 334 #endif
 335
 336 #ifdef DIR_SEPARATOR_2
 337   /* Convert DIR_SEPARATOR_2 to DIR_SEPARATOR.  */
 338   if (DIR_SEPARATOR_2 != DIR_SEPARATOR)
 339     tr (result, DIR_SEPARATOR_2, DIR_SEPARATOR);
 340 #endif
 341
 342 #if defined (DIR_SEPARATOR) && !defined (DIR_SEPARATOR_2)
 343   if (DIR_SEPARATOR != '/')
 344     tr (result, '/', DIR_SEPARATOR);
 345 #endif
 346
 347   return result;
 348 }
 349
 350 /* Reset the standard prefix.  */
 351 void
 352 set_std_prefix (const char *prefix, int len)
 353 {
 354   std_prefix = save_string (prefix, len);
 355 }