| /* Find path of executable. |
| Copyright (C) 1998-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <assert.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <sys/param.h> |
| #include <ldsodefs.h> |
| #include <sysdep.h> |
| |
| #include <dl-dst.h> |
| |
| /* On Linux >= 2.1 systems which have the dcache implementation we can get |
| the path of the application from the /proc/self/exe symlink. Try this |
| first and fall back on the generic method if necessary. */ |
| |
| const char * |
| _dl_get_origin (void) |
| { |
| char linkval[PATH_MAX]; |
| char *result; |
| int len; |
| INTERNAL_SYSCALL_DECL (err); |
| |
| len = INTERNAL_SYSCALL (readlink, err, 3, "/proc/self/exe", linkval, |
| sizeof (linkval)); |
| if (! INTERNAL_SYSCALL_ERROR_P (len, err) && len > 0 && linkval[0] != '[') |
| { |
| /* We can use this value. */ |
| assert (linkval[0] == '/'); |
| while (len > 1 && linkval[len - 1] != '/') |
| --len; |
| result = (char *) malloc (len + 1); |
| if (result == NULL) |
| result = (char *) -1; |
| else if (len == 1) |
| memcpy (result, "/", 2); |
| else |
| *((char *) __mempcpy (result, linkval, len - 1)) = '\0'; |
| } |
| else |
| { |
| result = (char *) -1; |
| /* We use the environment variable LD_ORIGIN_PATH. If it is set make |
| a copy and strip out trailing slashes. */ |
| if (GLRO(dl_origin_path) != NULL) |
| { |
| size_t len = strlen (GLRO(dl_origin_path)); |
| result = (char *) malloc (len + 1); |
| if (result == NULL) |
| result = (char *) -1; |
| else |
| { |
| char *cp = __mempcpy (result, GLRO(dl_origin_path), len); |
| while (cp > result + 1 && cp[-1] == '/') |
| --cp; |
| *cp = '\0'; |
| } |
| } |
| } |
| |
| return result; |
| } |