1 /* Provide relocatable packages. 2 Copyright (C) 2003 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno (at) clisp.org>, 2003. 4 5 This program is free software; you can redistribute it and/or modify it 6 under the terms of the GNU Library General Public License as published 7 by the Free Software Foundation; either version 2, or (at your option) 8 any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Library General Public License for more details. 14 15 You should have received a copy of the GNU Library General Public 16 License along with this program; if not, write to the Free Software 17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 18 USA. */ 19 20 21 /* Tell glibc's <stdio.h> to provide a prototype for getline(). 22 This must come before <config.h> because <config.h> may include 23 <features.h>, and once <features.h> has been included, it's too late. */ 24 #ifndef _GNU_SOURCE 25 # define _GNU_SOURCE 1 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 # include "config.h" 30 #endif 31 32 /* Specification. */ 33 #include "relocatable.h" 34 35 #if ENABLE_RELOCATABLE 36 37 #include <stddef.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 42 #ifdef NO_XMALLOC 43 # define xmalloc malloc 44 #else 45 # include "xalloc.h" 46 #endif 47 48 #if defined _WIN32 || defined __WIN32__ 49 # define WIN32_LEAN_AND_MEAN 50 # include <windows.h> 51 #endif 52 53 #if DEPENDS_ON_LIBCHARSET 54 # include <libcharset.h> 55 #endif 56 #if DEPENDS_ON_LIBICONV && HAVE_ICONV 57 # include <iconv.h> 58 #endif 59 #if DEPENDS_ON_LIBINTL && ENABLE_NLS 60 # include <libintl.h> 61 #endif 62 63 /* Faked cheap 'bool'. */ 64 #undef bool 65 #undef false 66 #undef true 67 #define bool int 68 #define false 0 69 #define true 1 70 71 /* Pathname support. 72 ISSLASH(C) tests whether C is a directory separator character. 73 IS_PATH_WITH_DIR(P) tests whether P contains a directory specification. 74 */ 75 #if defined _WIN32 || defined __WIN32__ || defined __EMX__ || defined __DJGPP__ 76 /* Win32, OS/2, DOS */ 77 # define ISSLASH(C) ((C) == '/' || (C) == '\\') 78 # define HAS_DEVICE(P) \ 79 ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \ 80 && (P)[1] == ':') 81 # define IS_PATH_WITH_DIR(P) \ 82 (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P)) 83 # define FILESYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0) 84 #else 85 /* Unix */ 86 # define ISSLASH(C) ((C) == '/') 87 # define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL) 88 # define FILESYSTEM_PREFIX_LEN(P) 0 89 #endif 90 91 /* Original installation prefix. */ 92 static char *orig_prefix; 93 static size_t orig_prefix_len; 94 /* Current installation prefix. */ 95 static char *curr_prefix; 96 static size_t curr_prefix_len; 97 /* These prefixes do not end in a slash. Anything that will be concatenated 98 to them must start with a slash. */ 99 100 /* Sets the original and the current installation prefix of this module. 101 Relocation simply replaces a pathname starting with the original prefix 102 by the corresponding pathname with the current prefix instead. Both 103 prefixes should be directory names without trailing slash (i.e. use "" 104 instead of "/"). */ 105 static void 106 set_this_relocation_prefix (const char *orig_prefix_arg, 107 const char *curr_prefix_arg) 108 { 109 if (orig_prefix_arg != NULL && curr_prefix_arg != NULL 110 /* Optimization: if orig_prefix and curr_prefix are equal, the 111 relocation is a nop. */ 112 && strcmp (orig_prefix_arg, curr_prefix_arg) != 0) 113 { 114 /* Duplicate the argument strings. */ 115 char *memory; 116 117 orig_prefix_len = strlen (orig_prefix_arg); 118 curr_prefix_len = strlen (curr_prefix_arg); 119 memory = (char *) xmalloc (orig_prefix_len + 1 + curr_prefix_len + 1); 120 #ifdef NO_XMALLOC 121 if (memory != NULL) 122 #endif 123 { 124 memcpy (memory, orig_prefix_arg, orig_prefix_len + 1); 125 orig_prefix = memory; 126 memory += orig_prefix_len + 1; 127 memcpy (memory, curr_prefix_arg, curr_prefix_len + 1); 128 curr_prefix = memory; 129 return; 130 } 131 } 132 orig_prefix = NULL; 133 curr_prefix = NULL; 134 /* Don't worry about wasted memory here - this function is usually only 135 called once. */ 136 } 137 138 /* Sets the original and the current installation prefix of the package. 139 Relocation simply replaces a pathname starting with the original prefix 140 by the corresponding pathname with the current prefix instead. Both 141 prefixes should be directory names without trailing slash (i.e. use "" 142 instead of "/"). */ 143 void 144 set_relocation_prefix (const char *orig_prefix_arg, const char *curr_prefix_arg) 145 { 146 set_this_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 147 148 /* Now notify all dependent libraries. */ 149 #if DEPENDS_ON_LIBCHARSET 150 libcharset_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 151 #endif 152 #if DEPENDS_ON_LIBICONV && HAVE_ICONV && _LIBICONV_VERSION >= 0x0109 153 libiconv_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 154 #endif 155 #if DEPENDS_ON_LIBINTL && ENABLE_NLS && defined libintl_set_relocation_prefix 156 libintl_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 157 #endif 158 } 159 160 #if !defined IN_LIBRARY || (defined PIC && defined INSTALLDIR) 161 162 /* Convenience function: 163 Computes the current installation prefix, based on the original 164 installation prefix, the original installation directory of a particular 165 file, and the current pathname of this file. Returns NULL upon failure. */ 166 #ifdef IN_LIBRARY 167 #define compute_curr_prefix local_compute_curr_prefix 168 static 169 #endif 170 const char * 171 compute_curr_prefix (const char *orig_installprefix, 172 const char *orig_installdir, 173 const char *curr_pathname) 174 { 175 const char *curr_installdir; 176 const char *rel_installdir; 177 178 if (curr_pathname == NULL) 179 return NULL; 180 181 /* Determine the relative installation directory, relative to the prefix. 182 This is simply the difference between orig_installprefix and 183 orig_installdir. */ 184 if (strncmp (orig_installprefix, orig_installdir, strlen (orig_installprefix)) 185 != 0) 186 /* Shouldn't happen - nothing should be installed outside $(prefix). */ 187 return NULL; 188 rel_installdir = orig_installdir + strlen (orig_installprefix); 189 190 /* Determine the current installation directory. */ 191 { 192 const char *p_base = curr_pathname + FILESYSTEM_PREFIX_LEN (curr_pathname); 193 const char *p = curr_pathname + strlen (curr_pathname); 194 char *q; 195 196 while (p > p_base) 197 { 198 p--; 199 if (ISSLASH (*p)) 200 break; 201 } 202 203 q = (char *) xmalloc (p - curr_pathname + 1); 204 #ifdef NO_XMALLOC 205 if (q == NULL) 206 return NULL; 207 #endif 208 memcpy (q, curr_pathname, p - curr_pathname); 209 q[p - curr_pathname] = '\0'; 210 curr_installdir = q; 211 } 212 213 /* Compute the current installation prefix by removing the trailing 214 rel_installdir from it. */ 215 { 216 const char *rp = rel_installdir + strlen (rel_installdir); 217 const char *cp = curr_installdir + strlen (curr_installdir); 218 const char *cp_base = 219 curr_installdir + FILESYSTEM_PREFIX_LEN (curr_installdir); 220 221 while (rp > rel_installdir && cp > cp_base) 222 { 223 bool same = false; 224 const char *rpi = rp; 225 const char *cpi = cp; 226 227 while (rpi > rel_installdir && cpi > cp_base) 228 { 229 rpi--; 230 cpi--; 231 if (ISSLASH (*rpi) || ISSLASH (*cpi)) 232 { 233 if (ISSLASH (*rpi) && ISSLASH (*cpi)) 234 same = true; 235 break; 236 } 237 #if defined _WIN32 || defined __WIN32__ || defined __EMX__ || defined __DJGPP__ 238 /* Win32, OS/2, DOS - case insignificant filesystem */ 239 if ((*rpi >= 'a' && *rpi <= 'z' ? *rpi - 'a' + 'A' : *rpi) 240 != (*cpi >= 'a' && *cpi <= 'z' ? *cpi - 'a' + 'A' : *cpi)) 241 break; 242 #else 243 if (*rpi != *cpi) 244 break; 245 #endif 246 } 247 if (!same) 248 break; 249 /* The last pathname component was the same. opi and cpi now point 250 to the slash before it. */ 251 rp = rpi; 252 cp = cpi; 253 } 254 255 if (rp > rel_installdir) 256 /* Unexpected: The curr_installdir does not end with rel_installdir. */ 257 return NULL; 258 259 { 260 size_t curr_prefix_len = cp - curr_installdir; 261 char *curr_prefix; 262 263 curr_prefix = (char *) xmalloc (curr_prefix_len + 1); 264 #ifdef NO_XMALLOC 265 if (curr_prefix == NULL) 266 return NULL; 267 #endif 268 memcpy (curr_prefix, curr_installdir, curr_prefix_len); 269 curr_prefix[curr_prefix_len] = '\0'; 270 271 return curr_prefix; 272 } 273 } 274 } 275 276 #endif /* !IN_LIBRARY || PIC */ 277 278 #if defined PIC && defined INSTALLDIR 279 280 /* Full pathname of shared library, or NULL. */ 281 static char *shared_library_fullname; 282 283 #if defined _WIN32 || defined __WIN32__ 284 285 /* Determine the full pathname of the shared library when it is loaded. */ 286 287 BOOL WINAPI 288 DllMain (HINSTANCE module_handle, DWORD event, LPVOID reserved) 289 { 290 (void) reserved; 291 292 if (event == DLL_PROCESS_ATTACH) 293 { 294 /* The DLL is being loaded into an application's address range. */ 295 static char location[MAX_PATH]; 296 297 if (!GetModuleFileName (module_handle, location, sizeof (location))) 298 /* Shouldn't happen. */ 299 return FALSE; 300 301 if (!IS_PATH_WITH_DIR (location)) 302 /* Shouldn't happen. */ 303 return FALSE; 304 305 shared_library_fullname = strdup (location); 306 } 307 308 return TRUE; 309 } 310 311 #else /* Unix */ 312 313 static void 314 find_shared_library_fullname () 315 { 316 #if defined __linux__ && __GLIBC__ >= 2 317 /* Linux has /proc/self/maps. glibc 2 has the getline() function. */ 318 FILE *fp; 319 320 /* Open the current process' maps file. It describes one VMA per line. */ 321 fp = fopen ("/proc/self/maps", "r"); 322 if (fp) 323 { 324 unsigned long address = (unsigned long) &find_shared_library_fullname; 325 for (;;) 326 { 327 unsigned long start, end; 328 int c; 329 330 if (fscanf (fp, "%lx-%lx", &start, &end) != 2) 331 break; 332 if (address >= start && address <= end - 1) 333 { 334 /* Found it. Now see if this line contains a filename. */ 335 while (c = getc (fp), c != EOF && c != '\n' && c != '/') 336 continue; 337 if (c == '/') 338 { 339 size_t size; 340 int len; 341 342 ungetc (c, fp); 343 shared_library_fullname = NULL; size = 0; 344 len = getline (&shared_library_fullname, &size, fp); 345 if (len >= 0) 346 { 347 /* Success: filled shared_library_fullname. */ 348 if (len > 0 && shared_library_fullname[len - 1] == '\n') 349 shared_library_fullname[len - 1] = '\0'; 350 } 351 } 352 break; 353 } 354 while (c = getc (fp), c != EOF && c != '\n') 355 continue; 356 } 357 fclose (fp); 358 } 359 #endif 360 } 361 362 #endif /* WIN32 / Unix */ 363 364 /* Return the full pathname of the current shared library. 365 Return NULL if unknown. 366 Guaranteed to work only on Linux and Woe32. */ 367 static char * 368 get_shared_library_fullname () 369 { 370 #if !(defined _WIN32 || defined __WIN32__) 371 static bool tried_find_shared_library_fullname; 372 if (!tried_find_shared_library_fullname) 373 { 374 find_shared_library_fullname (); 375 tried_find_shared_library_fullname = true; 376 } 377 #endif 378 return shared_library_fullname; 379 } 380 381 #endif /* PIC */ 382 383 /* Returns the pathname, relocated according to the current installation 384 directory. */ 385 const char * 386 relocate (const char *pathname) 387 { 388 #if defined PIC && defined INSTALLDIR 389 static int initialized; 390 391 /* Initialization code for a shared library. */ 392 if (!initialized) 393 { 394 /* At this point, orig_prefix and curr_prefix likely have already been 395 set through the main program's set_program_name_and_installdir 396 function. This is sufficient in the case that the library has 397 initially been installed in the same orig_prefix. But we can do 398 better, to also cover the cases that 1. it has been installed 399 in a different prefix before being moved to orig_prefix and (later) 400 to curr_prefix, 2. unlike the program, it has not moved away from 401 orig_prefix. */ 402 const char *orig_installprefix = INSTALLPREFIX; 403 const char *orig_installdir = INSTALLDIR; 404 const char *curr_prefix_better; 405 406 curr_prefix_better = 407 compute_curr_prefix (orig_installprefix, orig_installdir, 408 get_shared_library_fullname ()); 409 if (curr_prefix_better == NULL) 410 curr_prefix_better = curr_prefix; 411 412 set_relocation_prefix (orig_installprefix, curr_prefix_better); 413 414 initialized = 1; 415 } 416 #endif 417 418 /* Note: It is not necessary to perform case insensitive comparison here, 419 even for DOS-like filesystems, because the pathname argument was 420 typically created from the same Makefile variable as orig_prefix came 421 from. */ 422 if (orig_prefix != NULL && curr_prefix != NULL 423 && strncmp (pathname, orig_prefix, orig_prefix_len) == 0) 424 { 425 if (pathname[orig_prefix_len] == '\0') 426 /* pathname equals orig_prefix. */ 427 return curr_prefix; 428 if (ISSLASH (pathname[orig_prefix_len])) 429 { 430 /* pathname starts with orig_prefix. */ 431 const char *pathname_tail = &pathname[orig_prefix_len]; 432 char *result = 433 (char *) xmalloc (curr_prefix_len + strlen (pathname_tail) + 1); 434 435 #ifdef NO_XMALLOC 436 if (result != NULL) 437 #endif 438 { 439 memcpy (result, curr_prefix, curr_prefix_len); 440 strcpy (result + curr_prefix_len, pathname_tail); 441 return result; 442 } 443 } 444 } 445 /* Nothing to relocate. */ 446 return pathname; 447 } 448 449 #endif 450
