1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672
|
/*
* BinReloc - a library for creating relocatable executables
* Written by: Hongli Lai <h.lai@chello.nl>
* http://autopackage.org/
*
* This source code is public domain. You can relicense this code
* under whatever license you want.
*
* See http://autopackage.org/docs/binreloc/ for
* more information and how to use this.
*/
#ifndef __BINRELOC_C__
#define __BINRELOC_C__
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include "binreloc.h"
#include "config.h"
G_BEGIN_DECLS
/** @internal
* Find the canonical filename of the executable. Returns the filename
* (which must be freed) or NULL on error. If the parameter 'error' is
* not NULL, the error code will be stored there, if an error occured.
*/
static char *_br_find_exe(GbrInitError * error)
{
char *path, *path2, *line, *result;
size_t buf_size;
ssize_t size;
struct stat stat_buf;
FILE *f;
/* Read from /proc/self/exe (symlink) */
if (sizeof(path) > SSIZE_MAX)
buf_size = SSIZE_MAX - 1;
else
buf_size = PATH_MAX - 1;
path = (char *) g_try_malloc(buf_size);
if (path == NULL) {
/* Cannot allocate memory. */
if (error)
*error = GBR_INIT_ERROR_NOMEM;
return NULL;
}
path2 = (char *) g_try_malloc(buf_size);
if (path2 == NULL) {
/* Cannot allocate memory. */
if (error)
*error = GBR_INIT_ERROR_NOMEM;
g_free(path);
return NULL;
}
strncpy(path2, "/proc/self/exe", buf_size - 1);
while (1) {
int i;
size = readlink(path2, path, buf_size - 1);
if (size == -1) {
/* Error. */
g_free(path2);
break;
}
/* readlink() success. */
path[size] = '\0';
/* Check whether the symlink's target is also a symlink.
* We want to get the final target. */
i = stat(path, &stat_buf);
if (i == -1) {
/* Error. */
g_free(path2);
break;
}
/* stat() success. */
if (!S_ISLNK(stat_buf.st_mode)) {
/* path is not a symlink. Done. */
g_free(path2);
return path;
}
/* path is a symlink. Continue loop and resolve this. */
strncpy(path, path2, buf_size - 1);
}
/* readlink() or stat() failed; this can happen when the program is
* running in Valgrind 2.2. Read from /proc/self/maps as fallback. */
buf_size = PATH_MAX + 128;
line = (char *) g_try_realloc(path, buf_size);
if (line == NULL) {
/* Cannot allocate memory. */
g_free(path);
if (error)
*error = GBR_INIT_ERROR_NOMEM;
return NULL;
}
f = fopen("/proc/self/maps", "r");
if (f == NULL) {
g_free(line);
if (error)
*error = GBR_INIT_ERROR_OPEN_MAPS;
return NULL;
}
/* The first entry should be the executable name. */
result = fgets(line, (int) buf_size, f);
if (result == NULL) {
fclose(f);
g_free(line);
if (error)
*error = GBR_INIT_ERROR_READ_MAPS;
return NULL;
}
/* Get rid of newline character. */
buf_size = strlen(line);
if (buf_size <= 0) {
/* Huh? An empty string? */
fclose(f);
g_free(line);
if (error)
*error = GBR_INIT_ERROR_INVALID_MAPS;
return NULL;
}
if (line[buf_size - 1] == 10)
line[buf_size - 1] = 0;
/* Extract the filename; it is always an absolute path. */
path = strchr(line, '/');
/* Sanity check. */
if (strstr(line, " r-xp ") == NULL || path == NULL) {
fclose(f);
g_free(line);
if (error)
*error = GBR_INIT_ERROR_INVALID_MAPS;
return NULL;
}
path = g_strdup(path);
g_free(line);
fclose(f);
return path;
}
/** @internal
* Find the canonical filename of the executable which owns symbol.
* Returns a filename which must be freed, or NULL on error.
*/
static char *_br_find_exe_for_symbol(const void *symbol,
GbrInitError * error)
{
#define SIZE PATH_MAX + 100
FILE *f;
size_t address_string_len;
char *address_string, line[SIZE], *found;
if (symbol == NULL)
return (char *) NULL;
f = fopen("/proc/self/maps", "r");
if (f == NULL)
return (char *) NULL;
address_string_len = 4;
address_string = (char *) g_try_malloc(address_string_len);
found = (char *) NULL;
while (!feof(f)) {
char *start_addr, *end_addr, *end_addr_end, *file;
void *start_addr_p, *end_addr_p;
size_t len;
if (fgets(line, SIZE, f) == NULL)
break;
/* Sanity check. */
if (strstr(line, " r-xp ") == NULL || strchr(line, '/') == NULL)
continue;
/* Parse line. */
start_addr = line;
end_addr = strchr(line, '-');
file = strchr(line, '/');
/* More sanity check. */
if (!(file > end_addr && end_addr != NULL && end_addr[0] == '-'))
continue;
end_addr[0] = '\0';
end_addr++;
end_addr_end = strchr(end_addr, ' ');
if (end_addr_end == NULL)
continue;
end_addr_end[0] = '\0';
len = strlen(file);
if (len == 0)
continue;
if (file[len - 1] == '\n')
file[len - 1] = '\0';
/* Get rid of "(deleted)" from the filename. */
len = strlen(file);
if (len > 10 && strcmp(file + len - 10, " (deleted)") == 0)
file[len - 10] = '\0';
/* I don't know whether this can happen but better safe than sorry. */
len = strlen(start_addr);
if (len != strlen(end_addr))
continue;
/* Transform the addresses into a string in the form of 0xdeadbeef,
* then transform that into a pointer. */
if (address_string_len < len + 3) {
address_string_len = len + 3;
address_string =
(char *) g_try_realloc(address_string, address_string_len);
}
memcpy(address_string, "0x", 2);
memcpy(address_string + 2, start_addr, len);
address_string[2 + len] = '\0';
sscanf(address_string, "%p", &start_addr_p);
memcpy(address_string, "0x", 2);
memcpy(address_string + 2, end_addr, len);
address_string[2 + len] = '\0';
sscanf(address_string, "%p", &end_addr_p);
if (symbol >= start_addr_p && symbol < end_addr_p) {
found = file;
break;
}
}
g_free(address_string);
fclose(f);
if (found == NULL)
return (char *) NULL;
else
return g_strdup(found);
}
static gchar *exe = NULL;
static void set_gerror(GError ** error, GbrInitError errcode);
/** Initialize the BinReloc library (for applications).
*
* This function must be called before using any other BinReloc functions.
* It attempts to locate the application's canonical filename.
*
* @note If you want to use BinReloc for a library, then you should call
* gbr_init_lib() instead.
*
* @param error If BinReloc failed to initialize, then the error report will
* be stored in this variable. Set to NULL if you don't want an
* error report. See the #GbrInitError for a list of error
* codes.
*
* @returns TRUE on success, FALSE if BinReloc failed to initialize.
*/
gboolean gbr_init(GError ** error)
{
GbrInitError errcode = 0;
/* Locate the application's filename. */
exe = _br_find_exe(&errcode);
if (exe != NULL)
/* Success! */
return TRUE;
else {
/* Failed :-( */
set_gerror(error, errcode);
return FALSE;
}
}
/** Initialize the BinReloc library (for libraries).
*
* This function must be called before using any other BinReloc functions.
* It attempts to locate the calling library's canonical filename.
*
* @note The BinReloc source code MUST be included in your library, or this
* function won't work correctly.
*
* @returns TRUE on success, FALSE if a filename cannot be found.
*/
gboolean gbr_init_lib(GError ** error)
{
GbrInitError errcode = 0;
exe = _br_find_exe_for_symbol((const void *) "", &errcode);
if (exe != NULL)
/* Success! */
return TRUE;
else {
/* Failed :-( */
set_gerror(error, errcode);
return exe != NULL;
}
}
static void set_gerror(GError ** error, GbrInitError errcode)
{
gchar *error_message;
if (error == NULL)
return;
switch (errcode) {
case GBR_INIT_ERROR_NOMEM:
error_message = "Cannot allocate memory.";
break;
case GBR_INIT_ERROR_OPEN_MAPS:
error_message = "Unable to open /proc/self/maps for reading.";
break;
case GBR_INIT_ERROR_READ_MAPS:
error_message = "Unable to read from /proc/self/maps.";
break;
case GBR_INIT_ERROR_INVALID_MAPS:
error_message = "The file format of /proc/self/maps is invalid.";
break;
case GBR_INIT_ERROR_DISABLED:
error_message = "Binary relocation support is disabled.";
break;
default:
error_message = "Unknown error.";
break;
};
g_set_error(error, g_quark_from_static_string("GBinReloc"),
errcode, "%s", error_message);
}
/** Find the canonical filename of the current application.
*
* @param default_exe A default filename which will be used as fallback.
* @returns A string containing the application's canonical filename,
* which must be freed when no longer necessary. If BinReloc is
* not initialized, or if the initialization function failed,
* then a copy of default_exe will be returned. If default_exe
* is NULL, then NULL will be returned.
*/
gchar *gbr_find_exe(const gchar * default_exe)
{
if (exe == NULL) {
/* BinReloc is not initialized. */
if (default_exe != NULL)
return g_strdup(default_exe);
else
return NULL;
}
return g_strdup(exe);
}
/** Locate the directory in which the current application is installed.
*
* The prefix is generated by the following pseudo-code evaluation:
* \code
* dirname(exename)
* \endcode
*
* @param default_dir A default directory which will used as fallback.
* @return A string containing the directory, which must be freed when no
* longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_dir
* will be returned. If default_dir is NULL, then NULL will be
* returned.
*/
gchar *gbr_find_exe_dir(const gchar * default_dir)
{
if (exe == NULL) {
/* BinReloc not initialized. */
if (default_dir != NULL)
return g_strdup(default_dir);
else
return NULL;
}
return g_path_get_dirname(exe);
}
/** Locate the prefix in which the current application is installed.
*
* The prefix is generated by the following pseudo-code evaluation:
* \code
* dirname(dirname(exename))
* \endcode
*
* @param default_prefix A default prefix which will used as fallback.
* @return A string containing the prefix, which must be freed when no
* longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_prefix
* will be returned. If default_prefix is NULL, then NULL will be
* returned.
*/
gchar *gbr_find_prefix(const gchar * default_prefix)
{
gchar *dir1, *dir2;
if (exe == NULL) {
/* BinReloc not initialized. */
if (default_prefix != NULL)
return g_strdup(default_prefix);
else
return NULL;
}
dir1 = g_path_get_dirname(exe);
dir2 = g_path_get_dirname(dir1);
g_free(dir1);
return dir2;
}
/** Locate the application's binary folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/bin"
* \endcode
*
* @param default_bin_dir A default path which will used as fallback.
* @return A string containing the bin folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_bin_dir will
* be returned. If default_bin_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_bin_dir(const gchar * default_bin_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_bin_dir != NULL)
return g_strdup(default_bin_dir);
else
return NULL;
}
dir = g_build_filename(prefix, "bin", NULL);
g_free(prefix);
return dir;
}
/** Locate the application's superuser binary folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/sbin"
* \endcode
*
* @param default_sbin_dir A default path which will used as fallback.
* @return A string containing the sbin folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_sbin_dir will
* be returned. If default_bin_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_sbin_dir(const gchar * default_sbin_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_sbin_dir != NULL)
return g_strdup(default_sbin_dir);
else
return NULL;
}
dir = g_build_filename(prefix, "sbin", NULL);
g_free(prefix);
return dir;
}
/** Locate the application's data folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/share"
* \endcode
*
* @param default_data_dir A default path which will used as fallback.
* @return A string containing the data folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_data_dir
* will be returned. If default_data_dir is NULL, then NULL will be
* returned.
*/
gchar *gbr_find_data_dir(const gchar * default_data_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_data_dir != NULL)
return g_strdup(default_data_dir);
else
return NULL;
}
dir = g_build_filename(prefix, "share", NULL);
g_free(prefix);
return dir;
}
/** Locate the application's localization folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/share/locale"
* \endcode
*
* @param default_locale_dir A default path which will used as fallback.
* @return A string containing the localization folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_locale_dir will be returned.
* If default_locale_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_locale_dir(const gchar * default_locale_dir)
{
gchar *data_dir, *dir;
data_dir = gbr_find_data_dir(NULL);
if (data_dir == NULL) {
/* BinReloc not initialized. */
if (default_locale_dir != NULL)
return g_strdup(default_locale_dir);
else
return NULL;
}
dir = g_build_filename(data_dir, "locale", NULL);
g_free(data_dir);
return dir;
}
/** Locate the application's library folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/lib"
* \endcode
*
* @param default_lib_dir A default path which will used as fallback.
* @return A string containing the library folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the
* initialization function failed, then a copy of default_lib_dir will be returned.
* If default_lib_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_lib_dir(const gchar * default_lib_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_lib_dir != NULL)
return g_strdup(default_lib_dir);
else
return NULL;
}
#ifdef ARCH_x86_64
dir = g_build_filename(prefix, "lib", NULL);
#else
dir = g_build_filename(prefix, "lib", NULL);
#endif
g_free(prefix);
return dir;
}
/** Locate the application's libexec folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/libexec"
* \endcode
*
* @param default_libexec_dir A default path which will used as fallback.
* @return A string containing the libexec folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the initialization
* function failed, then a copy of default_libexec_dir will be returned.
* If default_libexec_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_libexec_dir(const gchar * default_libexec_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_libexec_dir != NULL)
return g_strdup(default_libexec_dir);
else
return NULL;
}
dir = g_build_filename(prefix, "libexec", NULL);
g_free(prefix);
return dir;
}
/** Locate the application's configuration files folder.
*
* The path is generated by the following pseudo-code evaluation:
* \code
* prefix + "/etc"
* \endcode
*
* @param default_etc_dir A default path which will used as fallback.
* @return A string containing the etc folder's path, which must be freed when
* no longer necessary. If BinReloc is not initialized, or if the initialization
* function failed, then a copy of default_etc_dir will be returned.
* If default_etc_dir is NULL, then NULL will be returned.
*/
gchar *gbr_find_etc_dir(const gchar * default_etc_dir)
{
gchar *prefix, *dir;
prefix = gbr_find_prefix(NULL);
if (prefix == NULL) {
/* BinReloc not initialized. */
if (default_etc_dir != NULL)
return g_strdup(default_etc_dir);
else
return NULL;
}
dir = g_build_filename(prefix, "etc", NULL);
g_free(prefix);
return dir;
}
G_END_DECLS
#endif /* __BINRELOC_C__ */
|