| /* Libiberty realpath. Like realpath, but more consistent behavior. |
| Based on gdb_realpath from GDB. |
| |
| Copyright (C) 2003-2021 Free Software Foundation, Inc. |
| |
| This file is part of the libiberty library. |
| |
| This program 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; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program 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 this program; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin Street - Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| /* |
| |
| @deftypefn Replacement {const char*} lrealpath (const char *@var{name}) |
| |
| Given a pointer to a string containing a pathname, returns a canonical |
| version of the filename. Symlinks will be resolved, and ``.'' and ``..'' |
| components will be simplified. The returned value will be allocated using |
| @code{malloc}, or @code{NULL} will be returned on a memory allocation error. |
| |
| @end deftypefn |
| |
| */ |
| |
| #include "config.h" |
| #include "ansidecl.h" |
| #include "libiberty.h" |
| |
| #ifdef HAVE_LIMITS_H |
| #include <limits.h> |
| #endif |
| #ifdef HAVE_STDLIB_H |
| #include <stdlib.h> |
| #endif |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #ifdef HAVE_STRING_H |
| #include <string.h> |
| #endif |
| |
| /* On GNU libc systems the declaration is only visible with _GNU_SOURCE. */ |
| #if defined(HAVE_CANONICALIZE_FILE_NAME) \ |
| && defined(NEED_DECLARATION_CANONICALIZE_FILE_NAME) |
| extern char *canonicalize_file_name (const char *); |
| #endif |
| |
| #if defined(HAVE_REALPATH) |
| # if defined (PATH_MAX) |
| # define REALPATH_LIMIT PATH_MAX |
| # else |
| # if defined (MAXPATHLEN) |
| # define REALPATH_LIMIT MAXPATHLEN |
| # endif |
| # endif |
| #else |
| /* cygwin has realpath, so it won't get here. */ |
| # if defined (_WIN32) |
| # define WIN32_LEAN_AND_MEAN |
| # include <windows.h> /* for GetFullPathName */ |
| # endif |
| #endif |
| |
| char * |
| lrealpath (const char *filename) |
| { |
| /* Method 1: The system has a compile time upper bound on a filename |
| path. Use that and realpath() to canonicalize the name. This is |
| the most common case. Note that, if there isn't a compile time |
| upper bound, you want to avoid realpath() at all costs. */ |
| #if defined(REALPATH_LIMIT) |
| { |
| char buf[REALPATH_LIMIT]; |
| const char *rp = realpath (filename, buf); |
| if (rp == NULL) |
| rp = filename; |
| return strdup (rp); |
| } |
| #endif /* REALPATH_LIMIT */ |
| |
| /* Method 2: The host system (i.e., GNU) has the function |
| canonicalize_file_name() which malloc's a chunk of memory and |
| returns that, use that. */ |
| #if defined(HAVE_CANONICALIZE_FILE_NAME) |
| { |
| char *rp = canonicalize_file_name (filename); |
| if (rp == NULL) |
| return strdup (filename); |
| else |
| return rp; |
| } |
| #endif |
| |
| /* Method 3: Now we're getting desperate! The system doesn't have a |
| compile time buffer size and no alternative function. Query the |
| OS, using pathconf(), for the buffer limit. Care is needed |
| though, some systems do not limit PATH_MAX (return -1 for |
| pathconf()) making it impossible to pass a correctly sized buffer |
| to realpath() (it could always overflow). On those systems, we |
| skip this. */ |
| #if defined (HAVE_REALPATH) && defined (HAVE_UNISTD_H) |
| { |
| /* Find out the max path size. */ |
| long path_max = pathconf ("/", _PC_PATH_MAX); |
| if (path_max > 0) |
| { |
| /* PATH_MAX is bounded. */ |
| char *buf, *rp, *ret; |
| buf = (char *) malloc (path_max); |
| if (buf == NULL) |
| return NULL; |
| rp = realpath (filename, buf); |
| ret = strdup (rp ? rp : filename); |
| free (buf); |
| return ret; |
| } |
| } |
| #endif |
| |
| /* The MS Windows method. If we don't have realpath, we assume we |
| don't have symlinks and just canonicalize to a Windows absolute |
| path. GetFullPath converts ../ and ./ in relative paths to |
| absolute paths, filling in current drive if one is not given |
| or using the current directory of a specified drive (eg, "E:foo"). |
| It also converts all forward slashes to back slashes. */ |
| #if defined (_WIN32) |
| { |
| char buf[MAX_PATH]; |
| char* basename; |
| DWORD len = GetFullPathName (filename, MAX_PATH, buf, &basename); |
| if (len == 0 || len > MAX_PATH - 1) |
| return strdup (filename); |
| else |
| { |
| /* The file system is case-preserving but case-insensitive, |
| Canonicalize to lowercase, using the codepage associated |
| with the process locale. */ |
| CharLowerBuff (buf, len); |
| return strdup (buf); |
| } |
| } |
| #endif |
| |
| /* This system is a lost cause, just duplicate the filename. */ |
| return strdup (filename); |
| } |