summaryrefslogtreecommitdiff
path: root/libiberty/lrealpath.c
diff options
context:
space:
mode:
authordrow <drow@138bc75d-0d04-0410-961f-82ee72b054a4>2003-02-20 22:11:13 +0000
committerdrow <drow@138bc75d-0d04-0410-961f-82ee72b054a4>2003-02-20 22:11:13 +0000
commit846a645c173e6d1b00187f1feed6104d13cb6ac1 (patch)
treee345914b98acba3281c7933fd21ce8beecd43bb6 /libiberty/lrealpath.c
parenta12d249cfc78fd9771fce1a54c9417b55b279fc1 (diff)
downloadgcc-846a645c173e6d1b00187f1feed6104d13cb6ac1.tar.gz
* Makefile.in (CFILES): Add lrealpath.c.
(REQUIRED_OFILES): Add lrealpath.o. (lrealpath.o): Add rule. * aclocal.m4 (libiberty_NEED_DECLARATION): Add. * configure.in: Add realpath and canonicalize_file_name to checkfuncs and AC_CHECK_FUNCS. Use libiberty_NEED_DECLARATION for canonicalize_file_name. * lrealpath.c: New file. * make-relative-prefix.c: Update documentation. (make_relative_prefix): Simplify. Use lbasename and lrealpath. * config.in: Regenerated. * configure: Regenerated. * functions.texi: Regenerated. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@63186 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'libiberty/lrealpath.c')
-rw-r--r--libiberty/lrealpath.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/libiberty/lrealpath.c b/libiberty/lrealpath.c
new file mode 100644
index 00000000000..b001b38ef66
--- /dev/null
+++ b/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);
+}