| /* Standard find_debuginfo callback for libdwfl. |
| Copyright (C) 2005, 2006, 2007 Red Hat, Inc. |
| This file is part of Red Hat elfutils. |
| |
| Red Hat elfutils is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by the |
| Free Software Foundation; version 2 of the License. |
| |
| Red Hat elfutils 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 |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License along |
| with Red Hat elfutils; if not, write to the Free Software Foundation, |
| Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. |
| |
| In addition, as a special exception, Red Hat, Inc. gives You the |
| additional right to link the code of Red Hat elfutils with code licensed |
| under any Open Source Initiative certified open source license |
| (http://www.opensource.org/licenses/index.php) which requires the |
| distribution of source code with any binary distribution and to |
| distribute linked combinations of the two. Non-GPL Code permitted under |
| this exception must only link to the code of Red Hat elfutils through |
| those well defined interfaces identified in the file named EXCEPTION |
| found in the source code files (the "Approved Interfaces"). The files |
| of Non-GPL Code may instantiate templates or use macros or inline |
| functions from the Approved Interfaces without causing the resulting |
| work to be covered by the GNU General Public License. Only Red Hat, |
| Inc. may make changes or additions to the list of Approved Interfaces. |
| Red Hat's grant of this exception is conditioned upon your not adding |
| any new exceptions. If you wish to add a new Approved Interface or |
| exception, please contact Red Hat. You must obey the GNU General Public |
| License in all respects for all of the Red Hat elfutils code and other |
| code used in conjunction with Red Hat elfutils except the Non-GPL Code |
| covered by this exception. If you modify this file, you may extend this |
| exception to your version of the file, but you are not obligated to do |
| so. If you do not wish to provide this exception without modification, |
| you must delete this exception statement from your version and license |
| this file solely under the GPL without exception. |
| |
| Red Hat elfutils is an included package of the Open Invention Network. |
| An included package of the Open Invention Network is a package for which |
| Open Invention Network licensees cross-license their patents. No patent |
| license is granted, either expressly or impliedly, by designation as an |
| included package. Should you wish to participate in the Open Invention |
| Network licensing program, please visit www.openinventionnetwork.com |
| <http://www.openinventionnetwork.com>. */ |
| |
| #include "libdwflP.h" |
| #include <stdio.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include "system.h" |
| |
| |
| /* Try to open64 [DIR/][SUBDIR/]DEBUGLINK, return file descriptor or -1. |
| On success, *DEBUGINFO_FILE_NAME has the malloc'd name of the open file. */ |
| static int |
| try_open (const char *dir, const char *subdir, const char *debuglink, |
| char **debuginfo_file_name) |
| { |
| char *fname; |
| if (dir == NULL && subdir == NULL) |
| { |
| fname = strdup (debuglink); |
| if (fname == NULL) |
| return -1; |
| } |
| else if ((subdir == NULL ? asprintf (&fname, "%s/%s", dir, debuglink) |
| : dir == NULL ? asprintf (&fname, "%s/%s", subdir, debuglink) |
| : asprintf (&fname, "%s/%s/%s", dir, subdir, debuglink)) < 0) |
| return -1; |
| |
| int fd = TEMP_FAILURE_RETRY (open64 (fname, O_RDONLY)); |
| if (fd < 0) |
| free (fname); |
| else |
| *debuginfo_file_name = fname; |
| |
| return fd; |
| } |
| |
| /* Return true iff the FD's contents CRC matches DEBUGLINK_CRC. */ |
| static inline bool |
| check_crc (int fd, GElf_Word debuglink_crc) |
| { |
| uint32_t file_crc; |
| return (__libdwfl_crc32_file (fd, &file_crc) == 0 |
| && file_crc == debuglink_crc); |
| } |
| |
| int |
| dwfl_standard_find_debuginfo (Dwfl_Module *mod, |
| void **userdata __attribute__ ((unused)), |
| const char *modname __attribute__ ((unused)), |
| GElf_Addr base __attribute__ ((unused)), |
| const char *file_name, |
| const char *debuglink_file, |
| GElf_Word debuglink_crc, |
| char **debuginfo_file_name) |
| { |
| bool cancheck = debuglink_crc != (GElf_Word) 0; |
| |
| const char *file_basename = file_name == NULL ? NULL : basename (file_name); |
| if (debuglink_file == NULL) |
| { |
| if (file_basename == NULL) |
| { |
| errno = 0; |
| return -1; |
| } |
| |
| size_t len = strlen (file_basename); |
| char *localname = alloca (len + sizeof ".debug"); |
| memcpy (localname, file_basename, len); |
| memcpy (&localname[len], ".debug", sizeof ".debug"); |
| debuglink_file = localname; |
| cancheck = false; |
| } |
| |
| /* Look for a file named DEBUGLINK_FILE in the directories |
| indicated by the debug directory path setting. */ |
| |
| const Dwfl_Callbacks *const cb = mod->dwfl->callbacks; |
| char *path = strdupa ((cb->debuginfo_path ? *cb->debuginfo_path : NULL) |
| ?: DEFAULT_DEBUGINFO_PATH); |
| |
| /* A leading - or + in the whole path sets whether to check file CRCs. */ |
| bool defcheck = true; |
| if (path[0] == '-' || path[0] == '+') |
| { |
| defcheck = path[0] == '+'; |
| ++path; |
| } |
| |
| char *file_dirname = (file_basename == file_name ? NULL |
| : strndupa (file_name, file_basename - 1 - file_name)); |
| char *p; |
| while ((p = strsep (&path, ":")) != NULL) |
| { |
| /* A leading - or + says whether to check file CRCs for this element. */ |
| bool check = defcheck; |
| if (*p == '+' || *p == '-') |
| check = *p++ == '+'; |
| check = check && cancheck; |
| |
| const char *dir, *subdir; |
| switch (p[0]) |
| { |
| case '\0': |
| /* An empty entry says to try the main file's directory. */ |
| dir = file_dirname; |
| subdir = NULL; |
| break; |
| case '/': |
| /* An absolute path says to look there for a subdirectory |
| named by the main file's absolute directory. |
| This cannot be applied to a relative file name. */ |
| if (file_dirname == NULL || file_dirname[0] != '/') |
| continue; |
| dir = p; |
| subdir = file_dirname + 1; |
| break; |
| default: |
| /* A relative path says to try a subdirectory of that name |
| in the main file's directory. */ |
| dir = file_dirname; |
| subdir = p; |
| break; |
| } |
| |
| char *fname; |
| int fd = try_open (dir, subdir, debuglink_file, &fname); |
| if (fd < 0) |
| switch (errno) |
| { |
| case ENOENT: |
| case ENOTDIR: |
| continue; |
| default: |
| return -1; |
| } |
| if (!check || check_crc (fd, debuglink_crc)) |
| { |
| *debuginfo_file_name = fname; |
| return fd; |
| } |
| free (fname); |
| close (fd); |
| } |
| |
| /* No dice. */ |
| errno = 0; |
| return -1; |
| } |
| INTDEF (dwfl_standard_find_debuginfo) |