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authorRoland McGrath <roland@gnu.org>1996-05-23 03:15:42 +0000
committerRoland McGrath <roland@gnu.org>1996-05-23 03:15:42 +0000
commitfa0bc87c32d02cd81ec4d0ae00e0d943c683e6e1 (patch)
tree197250e2e9e1f2c900d3bf042dbf14898dc0fb73 /stdlib/canonicalize.c
parente685238c901f1a7aa0c1956e63cc9f2de5599998 (diff)
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Wed May 22 22:10:01 1996 Roland McGrath <roland@delasyd.gnu.ai.mit.edu>
	* stdlib/canonicalize.c: New file.
	* stdlib/stdlib.h: Declare canonicalize_file_name, realpath.
	* stdlib/Makefile (routines): Add canonicalize.

	* posix/unistd.h: Declare __canonicalize_directory_name_internal.

Thu May 23 00:01:10 1996  Ulrich Drepper  <drepper@cygnus.com>

	* db/recno/rec_seq.c: Prevent `sccsid' definition by using the
	same #if condition as in the other db files.

	* intl/Makefile: Add -Wno-unused CFLAGS for compilation of
	bindtextdom.c, finddomain.c, and localealias.c.

	* intl/dcgettext.c: Don't define prototype for getcwd() when
	compiling in glibc.

	* libio/cleanup.c: Add prototype for _IO_register_cleanup.

	* libio/filedoalloc.c, libio/fileops.c, libio/iopopen.c: Don't
        define _POSIX_SOURCE unconditionally.

	* libio/filedoalloc.c, libio/iopopen.c: Include <unistd.h> if
        compiling in glibc.

	* libio/fileops.c (_IO_file_close_it): Don't sync file, call
	flush instead.  This relaxes the rules from POSIX.1 about
	changing the active handle a bit.

	* libio/iofopncook.c (struct _IO_cookie_file): Move definition
	into <libio.h>.
	Add prototypes for local functions to prevent warnings.

	* libio/iopopen.c: Change prototypes for _IO_fork, _IO_pipe, and
        _IO_DUP2 to contain complete parameter list.

	* libio/libio.h: Add definition of struct _IO_cookie_file.

	* libio/libioP.h: Add prototypes for _IO_vasprintf, _IO_vdprintf,
        and _IO_vsnprintf.

	* libio/memstream.c: Include <stdio.h>.

	* libio/stdio.h: Add prototypes for fopencookie,
        __stdio_gen_tempname, __vfscanf, __vsscanf, and __vsnprintf.

	* libio/strops.c: Avoid useless expression in `for' initializer.

	* locale/findlocale.c: Add some casts to prevent warnings.

	* locale/programs/locfile.c (write_locale_data): Don't use
	double `/' in locale binary file.

	* posix/unistd.h: Remove prototype for `reboot'.

	Update from bind-4.9.4-T1A.
	* resolv/Makefile (routines): Add inet_ntop and inet_pton.
	* resolv/arpa/nameser.h: Add definition of IN6ADDRSZ.
	* resolv/gethnamaddr.c, resolv/getnetnamadr.c, resolv/res_comp.c,
	resolv/res_debug.c, resolv/res_init.c

	* resolv/inet_ntop.c, resolv/inet_pton.c: New files.

	* resolv/resolv.h: Add RES_USE_INET6 flag.
	(__dn_isvalid): Renamed to __res_dnok.
	Add prototypes for __res_ownok and __res_mailok.

	* stdio-common/Makefile: Add -Wno-unused to CFLAGS for _itoa.c.

	* stdio-common/getline.c, stdio-common/vfscanf.c,
        sysdeps/posix/tempname.c: Don't use <ansidecl.h> anymore.

	* sysdeps/unix/sysv/linux/Makefile [$subdir == misc]
        (sysdep_routines): Add s_reboot.
	(install-others): Add $(includedir)/sys/syscall.h.
	New rule for $(includedir)/sys/syscall.h to produce from
	<asm/unistd.h>.

	* sysdeps/unix/sysv/linux/reboot.c: New file.  Make single
        argument function call 3 argument system call.

	* sysdeps/unix/sysv/linux/sys/reboot.h: New file.  Linux specific
	definition for reboot function.

	* sysdeps/unix/sysv/linux/syscall.h: Remove old and obsolete
        comment.

	* sysdeps/unix/sysv/linux/syscalls.list: Rename function for
	reboot syscall to __syscall_reboot.

	* wcsmbs/wchar.h: Protect prototypes for wcstof and wcstold by
	__USE_GNU, not USE_GNU.

Tue May 21 21:55:49 1996  David Mosberger-Tang  <davidm@AZStarNet.com>

	* locale/programs/charset.c, locale/programs/ld-collate.c:
	Add casts to prevent warnings on 64-bit machines.

	* locale/programs/ld-monetary.c: Don't do unnecessary tests for
	int_frac_digits and frac_digits which only produce warnings.

Mon May 13 23:45:29 1996  David Mosberger-Tang  <davidm@AZStarNet.com>

	* inet/arpa/inet.h: Backup return type of inet_addr to u_long.
	* resolv/inet_addr.c: Likewise.

	* resolv/Makefile (distribute): Add res_hconf.h
	(routines): Add res_hconf.

	* resolv/gethnamaddr.c: Add support for /etc/host.conf.

	* resolv/res_init.c: Initialize /etc/host.conf reader.

	* resolv/res_hconf.c, resolv/res_hconf.h: New files.
        Implementation of reading /etc/host.conf.

Wed May 22 21:21:15 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>

	* Rules (%.out rules): Prepend $($*-ENV) to the command.

	* sysdeps/unix/sysv/linux/i386/brk.c (___brk_addr): Define as weak
	alias for __curbrk.

Wed May 22 19:37:27 1996  Miles Bader  <miles@gnu.ai.mit.edu>

	* hurd/hurdexec.c (_hurd_exec): Pass INIT_TRACEMASK.
	* hurd/hurdmsg.c (set_int): Support INIT_TRACEMASK.

Wed May 22 18:47:31 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>

	* sysdeps/mach/hurd/getcwd.c
	(_hurd_canonicalize_directory_name_internal): New function, broken out
	of __getcwd.
	(__getcwd): Use it.
	(__canonicalize_directory_name_internal): New function using it.

	* sysdeps/posix/getcwd.c (__canonicalize_directory_name_internal): New
	function, broken out of __getcwd.
	(__getcwd): Use it.

Wed May 22 18:14:05 1996  Miles Bader  <miles@gnu.ai.mit.edu>

	* string/argz-create.c (__argz_create): Correctly calculate length.

	* string/argz-extract.c (__argz_extract): Add terminating 0 entry.
	* hurd/hurdstartup.c (_hurd_startup): ... and don't so here.

	[HAVE_VMSDIR_H]: Include "vmsdir.h".
	(glob) [VMS]: Don't grok ~.
Diffstat (limited to 'stdlib/canonicalize.c')
-rw-r--r--stdlib/canonicalize.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/stdlib/canonicalize.c b/stdlib/canonicalize.c
new file mode 100644
index 0000000000..55ac1bcf1d
--- /dev/null
+++ b/stdlib/canonicalize.c
@@ -0,0 +1,196 @@
+/* Return the canonical absolute name of a given file.
+Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+/* Return the canonical absolute name of file NAME.  The last file name
+   component need not exist, and may be a symlink to a nonexistent file.
+   If RESOLVED is null, the result is malloc'd; otherwise, if the canonical
+   name is PATH_MAX chars or more, returns null with `errno' set to
+   ENAMETOOLONG; if the name fits in fewer than PATH_MAX chars, returns the
+   name in RESOLVED.  */
+
+static char *
+canonicalize (const char *name, char *resolved)
+{
+  struct stat st;
+  const char *p;
+  long int path_max;
+  char *result, *dir, *end;
+  size_t namelen;
+
+  if (! resolved)
+    path_max = 0;
+  else
+    {
+#ifdef PATH_MAX
+      path_max = PATH_MAX;
+#else
+      path_max = sysconf (_SC_PATH_MAX);
+      if (path_max <= 0)
+	path_max = 1024;
+#endif
+    }
+
+  p = strrchr (name, '/');
+  if (!p)
+    {
+      dir = (char *) ".";
+      p = name;
+    }
+  else
+    {
+      if (p++ == name)
+	dir = (char *) "/";
+      else
+	{
+	  dir = __alloca (p - name);
+	  memcpy (dir, name, p - name - 1);
+	  dir[p - name] = '\0';
+	}
+    }
+
+  result = __canonicalize_directory_name_internal (dir, resolved, path_max);
+  if (!result)
+    return NULL;
+
+  /* Reconstruct the file name in the canonicalized directory.  */
+  namelen = strlen (name);
+  end = strchr (result, '\0');
+  if (resolved)
+    {
+      /* Make sure the name is not too long.  */
+      if (end - result + namelen > path_max)
+	{
+	  errno = ENAMETOOLONG;
+	  return NULL;
+	}
+    }
+  else
+    {
+      /* The name is dynamically allocated.  Extend it.  */
+      char *new = realloc (result, end - result + namelen + 1);
+      if (! new)
+	{
+	  free (result);
+	  return NULL;
+	}
+      end = new + (end - result);
+      result = new;
+    }
+  memcpy (end, name, namelen + 1);
+
+  while (__lstat (result, &st) == 0 && S_ISLNK (st.st_mode))
+    {
+      /* The file is a symlink.  Read its contents.  */
+      ssize_t n;
+    read_link_contents:
+      n = readlink (result, end,
+		    resolved ? result + path_max - end : namelen + 1);
+      if (n < 0)
+	/* Error reading the link contents.  */
+	return NULL;
+
+      if (end[0] == '/')
+	{
+	  /* Absolute symlink.  */
+	  if (resolved ? (end + n < result + path_max) : (n < namelen + 1))
+	    {
+	      /* It fit in our buffer, so we have the whole thing.  */
+	      memcpy (result, end, n);
+	      result[n] = '\0';
+	    }
+	  else if (resolved)
+	    {
+	      /* It didn't fit in the remainder of the buffer.  Either it
+		 fits in the entire buffer, or it doesn't.  Copy back the
+		 unresolved name onto the canonical directory and try once
+		 more.  */
+	      memcpy (end, name, namelen + 1);
+	      n = readlink (result, result, path_max);
+	      if (n < 0)
+		return NULL;
+	      if (n == path_max)
+		{
+		  errno = ENAMETOOLONG;
+		  return NULL;
+		}
+	      result[n] = '\0';
+	    }
+	  else
+	    /* Try again with a bigger buffer.  */
+	    goto extend_buffer;
+
+	  /* Check the resolved name for being a symlink too.  */
+	  continue;
+	}
+
+      if (resolved)
+	{
+	  if (end + n == result + path_max)
+	    {
+	      /* The link contents we read fill the buffer completely.
+		 There may be even more to read, and there is certainly no
+		 space for the null terminator.  */
+	      errno = ENAMETOOLONG;
+	      return NULL;
+	    }
+	}
+      else if (n == namelen + 1)
+      extend_buffer:
+	{
+	  /* The name buffer is dynamically allocated.  Extend it.  */
+	  char *new;
+
+	  /* Copy back the unresolved name onto the canonical directory.  */
+	  memcpy (end, name, namelen + 1);
+
+	  /* Make more space for readlink.  */
+	  namelen *= 2;
+	  new = realloc (result, end - result + namelen + 1);
+	  if (! new)
+	    {
+	      free (result);
+	      return NULL;
+	    }
+	  end = new + (end - result);
+	  result = new;
+
+	  goto read_link_contents;
+	}
+
+      /* Terminate the string; readlink does not.  */
+      end[n] = '\0';
+    }
+
+  return result;
+}
+
+weak_alias (canonicalize, realpath)
+
+char *
+canonicalize_file_name (const char *name)
+{
+  return canonicalize (name, NULL);
+}