1/* Provide relocatable packages. 2 Copyright (C) 2003-2006 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno@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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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#include <config.h> 29 30/* Specification. */ 31#include "relocatable.h" 32 33#if ENABLE_RELOCATABLE 34 35#include <stddef.h> 36#include <stdio.h> 37#include <stdlib.h> 38#include <string.h> 39 40#ifdef NO_XMALLOC 41# define xmalloc malloc 42#else 43# include "xalloc.h" 44#endif 45 46#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ 47# define WIN32_LEAN_AND_MEAN 48# include <windows.h> 49#endif 50 51#if DEPENDS_ON_LIBCHARSET 52# include <libcharset.h> 53#endif 54#if DEPENDS_ON_LIBICONV && HAVE_ICONV 55# include <iconv.h> 56#endif 57#if DEPENDS_ON_LIBINTL && ENABLE_NLS 58# include <libintl.h> 59#endif 60 61/* Faked cheap 'bool'. */ 62#undef bool 63#undef false 64#undef true 65#define bool int 66#define false 0 67#define true 1 68 69/* Pathname support. 70 ISSLASH(C) tests whether C is a directory separator character. 71 IS_PATH_WITH_DIR(P) tests whether P contains a directory specification. 72 */ 73#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__ 74 /* Win32, Cygwin, OS/2, DOS */ 75# define ISSLASH(C) ((C) == '/' || (C) == '\\') 76# define HAS_DEVICE(P) \ 77 ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \ 78 && (P)[1] == ':') 79# define IS_PATH_WITH_DIR(P) \ 80 (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P)) 81# define FILE_SYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0) 82#else 83 /* Unix */ 84# define ISSLASH(C) ((C) == '/') 85# define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL) 86# define FILE_SYSTEM_PREFIX_LEN(P) 0 87#endif 88 89/* Original installation prefix. */ 90static char *orig_prefix; 91static size_t orig_prefix_len; 92/* Current installation prefix. */ 93static char *curr_prefix; 94static size_t curr_prefix_len; 95/* These prefixes do not end in a slash. Anything that will be concatenated 96 to them must start with a slash. */ 97 98/* Sets the original and the current installation prefix of this module. 99 Relocation simply replaces a pathname starting with the original prefix 100 by the corresponding pathname with the current prefix instead. Both 101 prefixes should be directory names without trailing slash (i.e. use "" 102 instead of "/"). */ 103static void 104set_this_relocation_prefix (const char *orig_prefix_arg, 105 const char *curr_prefix_arg) 106{ 107 if (orig_prefix_arg != NULL && curr_prefix_arg != NULL 108 /* Optimization: if orig_prefix and curr_prefix are equal, the 109 relocation is a nop. */ 110 && strcmp (orig_prefix_arg, curr_prefix_arg) != 0) 111 { 112 /* Duplicate the argument strings. */ 113 char *memory; 114 115 orig_prefix_len = strlen (orig_prefix_arg); 116 curr_prefix_len = strlen (curr_prefix_arg); 117 memory = (char *) xmalloc (orig_prefix_len + 1 + curr_prefix_len + 1); 118#ifdef NO_XMALLOC 119 if (memory != NULL) 120#endif 121 { 122 memcpy (memory, orig_prefix_arg, orig_prefix_len + 1); 123 orig_prefix = memory; 124 memory += orig_prefix_len + 1; 125 memcpy (memory, curr_prefix_arg, curr_prefix_len + 1); 126 curr_prefix = memory; 127 return; 128 } 129 } 130 orig_prefix = NULL; 131 curr_prefix = NULL; 132 /* Don't worry about wasted memory here - this function is usually only 133 called once. */ 134} 135 136/* Sets the original and the current installation prefix of the package. 137 Relocation simply replaces a pathname starting with the original prefix 138 by the corresponding pathname with the current prefix instead. Both 139 prefixes should be directory names without trailing slash (i.e. use "" 140 instead of "/"). */ 141void 142set_relocation_prefix (const char *orig_prefix_arg, const char *curr_prefix_arg) 143{ 144 set_this_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 145 146 /* Now notify all dependent libraries. */ 147#if DEPENDS_ON_LIBCHARSET 148 libcharset_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 149#endif 150#if DEPENDS_ON_LIBICONV && HAVE_ICONV && _LIBICONV_VERSION >= 0x0109 151 libiconv_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 152#endif 153#if DEPENDS_ON_LIBINTL && ENABLE_NLS && defined libintl_set_relocation_prefix 154 libintl_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg); 155#endif 156} 157 158#if !defined IN_LIBRARY || (defined PIC && defined INSTALLDIR) 159 160/* Convenience function: 161 Computes the current installation prefix, based on the original 162 installation prefix, the original installation directory of a particular 163 file, and the current pathname of this file. Returns NULL upon failure. */ 164#ifdef IN_LIBRARY 165#define compute_curr_prefix local_compute_curr_prefix 166static 167#endif 168const char * 169compute_curr_prefix (const char *orig_installprefix, 170 const char *orig_installdir, 171 const char *curr_pathname) 172{ 173 const char *curr_installdir; 174 const char *rel_installdir; 175 176 if (curr_pathname == NULL) 177 return NULL; 178 179 /* Determine the relative installation directory, relative to the prefix. 180 This is simply the difference between orig_installprefix and 181 orig_installdir. */ 182 if (strncmp (orig_installprefix, orig_installdir, strlen (orig_installprefix)) 183 != 0) 184 /* Shouldn't happen - nothing should be installed outside $(prefix). */ 185 return NULL; 186 rel_installdir = orig_installdir + strlen (orig_installprefix); 187 188 /* Determine the current installation directory. */ 189 { 190 const char *p_base = curr_pathname + FILE_SYSTEM_PREFIX_LEN (curr_pathname); 191 const char *p = curr_pathname + strlen (curr_pathname); 192 char *q; 193 194 while (p > p_base) 195 { 196 p--; 197 if (ISSLASH (*p)) 198 break; 199 } 200 201 q = (char *) xmalloc (p - curr_pathname + 1); 202#ifdef NO_XMALLOC 203 if (q == NULL) 204 return NULL; 205#endif 206 memcpy (q, curr_pathname, p - curr_pathname); 207 q[p - curr_pathname] = '\0'; 208 curr_installdir = q; 209 } 210 211 /* Compute the current installation prefix by removing the trailing 212 rel_installdir from it. */ 213 { 214 const char *rp = rel_installdir + strlen (rel_installdir); 215 const char *cp = curr_installdir + strlen (curr_installdir); 216 const char *cp_base = 217 curr_installdir + FILE_SYSTEM_PREFIX_LEN (curr_installdir); 218 219 while (rp > rel_installdir && cp > cp_base) 220 { 221 bool same = false; 222 const char *rpi = rp; 223 const char *cpi = cp; 224 225 while (rpi > rel_installdir && cpi > cp_base) 226 { 227 rpi--; 228 cpi--; 229 if (ISSLASH (*rpi) || ISSLASH (*cpi)) 230 { 231 if (ISSLASH (*rpi) && ISSLASH (*cpi)) 232 same = true; 233 break; 234 } 235 /* Do case-insensitive comparison if the filesystem is always or 236 often case-insensitive. It's better to accept the comparison 237 if the difference is only in case, rather than to fail. */ 238#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__ 239 /* Win32, Cygwin, OS/2, DOS - case insignificant filesystem */ 240 if ((*rpi >= 'a' && *rpi <= 'z' ? *rpi - 'a' + 'A' : *rpi) 241 != (*cpi >= 'a' && *cpi <= 'z' ? *cpi - 'a' + 'A' : *cpi)) 242 break; 243#else 244 if (*rpi != *cpi) 245 break; 246#endif 247 } 248 if (!same) 249 break; 250 /* The last pathname component was the same. opi and cpi now point 251 to the slash before it. */ 252 rp = rpi; 253 cp = cpi; 254 } 255 256 if (rp > rel_installdir) 257 /* Unexpected: The curr_installdir does not end with rel_installdir. */ 258 return NULL; 259 260 { 261 size_t curr_prefix_len = cp - curr_installdir; 262 char *curr_prefix; 263 264 curr_prefix = (char *) xmalloc (curr_prefix_len + 1); 265#ifdef NO_XMALLOC 266 if (curr_prefix == NULL) 267 return NULL; 268#endif 269 memcpy (curr_prefix, curr_installdir, curr_prefix_len); 270 curr_prefix[curr_prefix_len] = '\0'; 271 272 return curr_prefix; 273 } 274 } 275} 276 277#endif /* !IN_LIBRARY || PIC */ 278 279#if defined PIC && defined INSTALLDIR 280 281/* Full pathname of shared library, or NULL. */ 282static char *shared_library_fullname; 283 284#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ 285 286/* Determine the full pathname of the shared library when it is loaded. */ 287 288BOOL WINAPI 289DllMain (HINSTANCE module_handle, DWORD event, LPVOID reserved) 290{ 291 (void) reserved; 292 293 if (event == DLL_PROCESS_ATTACH) 294 { 295 /* The DLL is being loaded into an application's address range. */ 296 static char location[MAX_PATH]; 297 298 if (!GetModuleFileName (module_handle, location, sizeof (location))) 299 /* Shouldn't happen. */ 300 return FALSE; 301 302 if (!IS_PATH_WITH_DIR (location)) 303 /* Shouldn't happen. */ 304 return FALSE; 305 306 { 307#if defined __CYGWIN__ 308 /* On Cygwin, we need to convert paths coming from Win32 system calls 309 to the Unix-like slashified notation. */ 310 static char location_as_posix_path[2 * MAX_PATH]; 311 /* There's no error return defined for cygwin_conv_to_posix_path. 312 See cygwin-api/func-cygwin-conv-to-posix-path.html. 313 Does it overflow the buffer of expected size MAX_PATH or does it 314 truncate the path? I don't know. Let's catch both. */ 315 cygwin_conv_to_posix_path (location, location_as_posix_path); 316 location_as_posix_path[MAX_PATH - 1] = '\0'; 317 if (strlen (location_as_posix_path) >= MAX_PATH - 1) 318 /* A sign of buffer overflow or path truncation. */ 319 return FALSE; 320 shared_library_fullname = strdup (location_as_posix_path); 321#else 322 shared_library_fullname = strdup (location); 323#endif 324 } 325 } 326 327 return TRUE; 328} 329 330#else /* Unix except Cygwin */ 331 332static void 333find_shared_library_fullname () 334{ 335#if defined __linux__ && __GLIBC__ >= 2 336 /* Linux has /proc/self/maps. glibc 2 has the getline() function. */ 337 FILE *fp; 338 339 /* Open the current process' maps file. It describes one VMA per line. */ 340 fp = fopen ("/proc/self/maps", "r"); 341 if (fp) 342 { 343 unsigned long address = (unsigned long) &find_shared_library_fullname; 344 for (;;) 345 { 346 unsigned long start, end; 347 int c; 348 349 if (fscanf (fp, "%lx-%lx", &start, &end) != 2) 350 break; 351 if (address >= start && address <= end - 1) 352 { 353 /* Found it. Now see if this line contains a filename. */ 354 while (c = getc (fp), c != EOF && c != '\n' && c != '/') 355 continue; 356 if (c == '/') 357 { 358 size_t size; 359 int len; 360 361 ungetc (c, fp); 362 shared_library_fullname = NULL; size = 0; 363 len = getline (&shared_library_fullname, &size, fp); 364 if (len >= 0) 365 { 366 /* Success: filled shared_library_fullname. */ 367 if (len > 0 && shared_library_fullname[len - 1] == '\n') 368 shared_library_fullname[len - 1] = '\0'; 369 } 370 } 371 break; 372 } 373 while (c = getc (fp), c != EOF && c != '\n') 374 continue; 375 } 376 fclose (fp); 377 } 378#endif 379} 380 381#endif /* (WIN32 or Cygwin) / (Unix except Cygwin) */ 382 383/* Return the full pathname of the current shared library. 384 Return NULL if unknown. 385 Guaranteed to work only on Linux, Cygwin and Woe32. */ 386static char * 387get_shared_library_fullname () 388{ 389#if !(defined _WIN32 || defined __WIN32__ || defined __CYGWIN__) 390 static bool tried_find_shared_library_fullname; 391 if (!tried_find_shared_library_fullname) 392 { 393 find_shared_library_fullname (); 394 tried_find_shared_library_fullname = true; 395 } 396#endif 397 return shared_library_fullname; 398} 399 400#endif /* PIC */ 401 402/* Returns the pathname, relocated according to the current installation 403 directory. */ 404const char * 405relocate (const char *pathname) 406{ 407#if defined PIC && defined INSTALLDIR 408 static int initialized; 409 410 /* Initialization code for a shared library. */ 411 if (!initialized) 412 { 413 /* At this point, orig_prefix and curr_prefix likely have already been 414 set through the main program's set_program_name_and_installdir 415 function. This is sufficient in the case that the library has 416 initially been installed in the same orig_prefix. But we can do 417 better, to also cover the cases that 1. it has been installed 418 in a different prefix before being moved to orig_prefix and (later) 419 to curr_prefix, 2. unlike the program, it has not moved away from 420 orig_prefix. */ 421 const char *orig_installprefix = INSTALLPREFIX; 422 const char *orig_installdir = INSTALLDIR; 423 const char *curr_prefix_better; 424 425 curr_prefix_better = 426 compute_curr_prefix (orig_installprefix, orig_installdir, 427 get_shared_library_fullname ()); 428 if (curr_prefix_better == NULL) 429 curr_prefix_better = curr_prefix; 430 431 set_relocation_prefix (orig_installprefix, curr_prefix_better); 432 433 initialized = 1; 434 } 435#endif 436 437 /* Note: It is not necessary to perform case insensitive comparison here, 438 even for DOS-like filesystems, because the pathname argument was 439 typically created from the same Makefile variable as orig_prefix came 440 from. */ 441 if (orig_prefix != NULL && curr_prefix != NULL 442 && strncmp (pathname, orig_prefix, orig_prefix_len) == 0) 443 { 444 if (pathname[orig_prefix_len] == '\0') 445 /* pathname equals orig_prefix. */ 446 return curr_prefix; 447 if (ISSLASH (pathname[orig_prefix_len])) 448 { 449 /* pathname starts with orig_prefix. */ 450 const char *pathname_tail = &pathname[orig_prefix_len]; 451 char *result = 452 (char *) xmalloc (curr_prefix_len + strlen (pathname_tail) + 1); 453 454#ifdef NO_XMALLOC 455 if (result != NULL) 456#endif 457 { 458 memcpy (result, curr_prefix, curr_prefix_len); 459 strcpy (result + curr_prefix_len, pathname_tail); 460 return result; 461 } 462 } 463 } 464 /* Nothing to relocate. */ 465 return pathname; 466} 467 468#endif 469