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Diffstat (limited to 'contrib/binutils/libiberty/lrealpath.c')
-rw-r--r-- | contrib/binutils/libiberty/lrealpath.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/contrib/binutils/libiberty/lrealpath.c b/contrib/binutils/libiberty/lrealpath.c new file mode 100644 index 0000000..b001b38 --- /dev/null +++ b/contrib/binutils/libiberty/lrealpath.c @@ -0,0 +1,128 @@ +/* Libiberty realpath. Like realpath, but more consistent behavior. + Based on gdb_realpath from GDB. + + Copyright 2003 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., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, 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 +#endif + +char * +lrealpath (filename) + 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 = malloc (path_max); + if (buf == NULL) + return NULL; + rp = realpath (filename, buf); + ret = strdup (rp ? rp : filename); + free (buf); + return ret; + } + } +#endif + + /* This system is a lost cause, just duplicate the filename. */ + return strdup (filename); +} |