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
|
/*
* BinReloc - a library for creating relocatable executables
* Written by: Mike Hearn <mike@theoretic.com>
* 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.
*
* NOTE: if you're using C++ and are getting "undefined reference
* to br_*", try renaming prefix.c to prefix.cpp
*/
/* WARNING, BEFORE YOU MODIFY PREFIX.C:
*
* If you make changes to any of the functions in prefix.c, you MUST
* change the BR_NAMESPACE macro (in prefix.h).
* This way you can avoid symbol table conflicts with other libraries
* that also happen to use BinReloc.
*
* Example:
* #define BR_NAMESPACE(funcName) foobar_ ## funcName
* --> expands br_locate to foobar_br_locate
*/
#ifndef _PREFIX_C_
#define _PREFIX_C_
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifndef BR_PTHREADS
/* Change 1 to 0 if you don't want pthread support */
#define BR_PTHREADS 1
#endif /* BR_PTHREADS */
#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
#include <string.h>
#include "prefix.h"
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#undef NULL
#define NULL ((void *) 0)
#ifdef __GNUC__
#define br_return_val_if_fail(expr,val) if (!(expr)) {fprintf (stderr, "** BinReloc (%s): assertion %s failed\n", __PRETTY_FUNCTION__, #expr); return val;}
#else
#define br_return_val_if_fail(expr,val) if (!(expr)) return val
#endif /* __GNUC__ */
static br_locate_fallback_func fallback_func = (br_locate_fallback_func) NULL;
static void *fallback_data = NULL;
#ifdef ENABLE_BINRELOC
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <unistd.h>
/**
* br_locate:
* symbol: A symbol that belongs to the app/library you want to locate.
* Returns: A newly allocated string containing the full path of the
* app/library that func belongs to, or NULL on error. This
* string should be freed when not when no longer needed.
*
* Finds out to which application or library symbol belongs, then locate
* the full path of that application or library.
* Note that symbol cannot be a pointer to a function. That will not work.
*
* Example:
* --> main.c
* #include "prefix.h"
* #include "libfoo.h"
*
* int main (int argc, char *argv[]) {
* printf ("Full path of this app: %s\n", br_locate (&argc));
* libfoo_start ();
* return 0;
* }
*
* --> libfoo.c starts here
* #include "prefix.h"
*
* void libfoo_start () {
* --> "" is a symbol that belongs to libfoo (because it's called
* --> from libfoo_start()); that's why this works.
* printf ("libfoo is located in: %s\n", br_locate (""));
* }
*/
char *
br_locate (void *symbol)
{
char line[5000];
FILE *f;
char *path;
br_return_val_if_fail (symbol != NULL, NULL);
f = fopen ("/proc/self/maps", "r");
if (!f) {
if (fallback_func)
return fallback_func(symbol, fallback_data);
else
return NULL;
}
while (!feof (f))
{
unsigned long start, end;
if (!fgets (line, sizeof (line), f))
continue;
if (!strstr (line, " r-xp ") || !strchr (line, '/'))
continue;
sscanf (line, "%lx-%lx ", &start, &end);
if (symbol >= (void *) start && symbol < (void *) end)
{
char *tmp;
size_t len;
/* Extract the filename; it is always an absolute path */
path = strchr (line, '/');
/* Get rid of the newline */
tmp = strrchr (path, '\n');
if (tmp) *tmp = 0;
/* Get rid of "(deleted)" */
len = strlen (path);
if (len > 10 && strcmp (path + len - 10, " (deleted)") == 0)
{
tmp = path + len - 10;
*tmp = 0;
}
fclose(f);
return strdup (path);
}
}
fclose (f);
return NULL;
}
/**
* br_locate_prefix:
* symbol: A symbol that belongs to the app/library you want to locate.
* Returns: A prefix. This string should be freed when no longer needed.
*
* Locates the full path of the app/library that symbol belongs to, and return
* the prefix of that path, or NULL on error.
* Note that symbol cannot be a pointer to a function. That will not work.
*
* Example:
* --> This application is located in /usr/bin/foo
* br_locate_prefix (&argc); --> returns: "/usr"
*/
char *
br_locate_prefix (void *symbol)
{
char *path, *prefix;
br_return_val_if_fail (symbol != NULL, NULL);
path = br_locate (symbol);
if (!path) return NULL;
prefix = br_extract_prefix (path);
free (path);
return prefix;
}
/**
* br_prepend_prefix:
* symbol: A symbol that belongs to the app/library you want to locate.
* path: The path that you want to prepend the prefix to.
* Returns: The new path, or NULL on error. This string should be freed when no
* longer needed.
*
* Gets the prefix of the app/library that symbol belongs to. Prepend that prefix to path.
* Note that symbol cannot be a pointer to a function. That will not work.
*
* Example:
* --> The application is /usr/bin/foo
* br_prepend_prefix (&argc, "/share/foo/data.png"); --> Returns "/usr/share/foo/data.png"
*/
char *
br_prepend_prefix (void *symbol, char *path)
{
char *tmp, *newpath;
br_return_val_if_fail (symbol != NULL, NULL);
br_return_val_if_fail (path != NULL, NULL);
tmp = br_locate_prefix (symbol);
if (!tmp) return NULL;
if (strcmp (tmp, "/") == 0)
newpath = strdup (path);
else
newpath = br_strcat (tmp, path);
/* Get rid of compiler warning ("br_prepend_prefix never used") */
if (0) br_prepend_prefix (NULL, NULL);
free (tmp);
return newpath;
}
#endif /* ENABLE_BINRELOC */
/* Pthread stuff for thread safetiness */
#if BR_PTHREADS && defined(ENABLE_BINRELOC)
#include <pthread.h>
static pthread_key_t br_thread_key;
static pthread_once_t br_thread_key_once = PTHREAD_ONCE_INIT;
static void
br_thread_local_store_fini ()
{
char *specific;
specific = (char *) pthread_getspecific (br_thread_key);
if (specific)
{
free (specific);
pthread_setspecific (br_thread_key, NULL);
}
pthread_key_delete (br_thread_key);
br_thread_key = 0;
}
static void
br_str_free (void *str)
{
if (str)
free (str);
}
static void
br_thread_local_store_init ()
{
if (pthread_key_create (&br_thread_key, br_str_free) == 0)
atexit (br_thread_local_store_fini);
}
#else /* BR_PTHREADS */
#ifdef ENABLE_BINRELOC
static char *br_last_value = (char *) NULL;
static void
br_free_last_value ()
{
if (br_last_value)
free (br_last_value);
}
#endif /* ENABLE_BINRELOC */
#endif /* BR_PTHREADS */
#ifdef ENABLE_BINRELOC
/**
* br_thread_local_store:
* str: A dynamically allocated string.
* Returns: str. This return value must not be freed.
*
* Store str in a thread-local variable and return str. The next
* you run this function, that variable is freed too.
* This function is created so you don't have to worry about freeing
* strings. Just be careful about doing this sort of thing:
*
* some_function( BR_DATADIR("/one.png"), BR_DATADIR("/two.png") )
*
* Examples:
* char *foo;
* foo = br_thread_local_store (strdup ("hello")); --> foo == "hello"
* foo = br_thread_local_store (strdup ("world")); --> foo == "world"; "hello" is now freed.
*/
const char *
br_thread_local_store (char *str)
{
#if BR_PTHREADS
char *specific;
pthread_once (&br_thread_key_once, br_thread_local_store_init);
specific = (char *) pthread_getspecific (br_thread_key);
br_str_free (specific);
pthread_setspecific (br_thread_key, str);
#else /* BR_PTHREADS */
static int initialized = 0;
if (!initialized)
{
atexit (br_free_last_value);
initialized = 1;
}
if (br_last_value)
free (br_last_value);
br_last_value = str;
#endif /* BR_PTHREADS */
return (const char *) str;
}
#endif /* ENABLE_BINRELOC */
/**
* br_strcat:
* str1: A string.
* str2: Another string.
* Returns: A newly-allocated string. This string should be freed when no longer needed.
*
* Concatenate str1 and str2 to a newly allocated string.
*/
char *
br_strcat (const char *str1, const char *str2)
{
char *result;
size_t len1, len2;
if (!str1) str1 = "";
if (!str2) str2 = "";
len1 = strlen (str1);
len2 = strlen (str2);
result = (char *) malloc (len1 + len2 + 1);
memcpy (result, str1, len1);
memcpy (result + len1, str2, len2);
result[len1 + len2] = '\0';
return result;
}
/* Emulates glibc's strndup() */
static char *
br_strndup (char *str, size_t size)
{
char *result = (char *) NULL;
size_t len;
br_return_val_if_fail (str != (char *) NULL, (char *) NULL);
len = strlen (str);
if (!len) return strdup ("");
if (size > len) size = len;
result = (char *) calloc (sizeof (char), len + 1);
memcpy (result, str, size);
return result;
}
/**
* br_extract_dir:
* path: A path.
* Returns: A directory name. This string should be freed when no longer needed.
*
* Extracts the directory component of path. Similar to g_dirname() or the dirname
* commandline application.
*
* Example:
* br_extract_dir ("/usr/local/foobar"); --> Returns: "/usr/local"
*/
char *
br_extract_dir (const char *path)
{
char *end, *result;
br_return_val_if_fail (path != (char *) NULL, (char *) NULL);
end = strrchr (path, '/');
if (!end) return strdup (".");
while (end > path && *end == '/')
end--;
result = br_strndup ((char *) path, end - path + 1);
if (!*result)
{
free (result);
return strdup ("/");
} else
return result;
}
/**
* br_extract_prefix:
* path: The full path of an executable or library.
* Returns: The prefix, or NULL on error. This string should be freed when no longer needed.
*
* Extracts the prefix from path. This function assumes that your executable
* or library is installed in an LSB-compatible directory structure.
*
* Example:
* br_extract_prefix ("/usr/bin/gnome-panel"); --> Returns "/usr"
* br_extract_prefix ("/usr/local/lib/libfoo.so"); --> Returns "/usr/local"
* br_extract_prefix ("/usr/local/libfoo.so"); --> Returns "/usr"
*/
char *
br_extract_prefix (const char *path)
{
char *end, *tmp, *result;
br_return_val_if_fail (path != (char *) NULL, (char *) NULL);
if (!*path) return strdup ("/");
end = strrchr (path, '/');
if (!end) return strdup (path);
tmp = br_strndup ((char *) path, end - path);
if (!*tmp)
{
free (tmp);
return strdup ("/");
}
end = strrchr (tmp, '/');
if (!end) return tmp;
result = br_strndup (tmp, end - tmp);
free (tmp);
if (!*result)
{
free (result);
result = strdup ("/");
}
return result;
}
/**
* br_set_fallback_function:
* func: A function to call to find the binary.
* data: User data to pass to func.
*
* Sets a function to call to find the path to the binary, in
* case "/proc/self/maps" can't be opened. The function set should
* return a string that is safe to free with free().
*/
void
br_set_locate_fallback_func (br_locate_fallback_func func, void *data)
{
fallback_func = func;
fallback_data = data;
}
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* _PREFIX_C */
|