From: Eric Blake <ebb9@byu.net>
Date: Thu, 10 Sep 2009 23:21:09 +0000 (-0600)
Subject: canonicalize, canonicalize-lgpl: honor // if distinct from /
X-Git-Tag: v0.1~5468
X-Git-Url: http://erislabs.org.uk/gitweb/?a=commitdiff_plain;h=35bd2ff772f9bc95f8e9d8e2a9bb5fc09331ed9c;p=gnulib.git

canonicalize, canonicalize-lgpl: honor // if distinct from /

* modules/canonicalize (Files): Add double-slash-root.m4.
* modules/canonicalize-lgpl (Files): Likewise.
* m4/canonicalize.m4 (gl_FUNC_CANONICALIZE_FILENAME_MODE)
(gl_CANONICALIZE_LGPL_SEPARATE): Add dependency.
* lib/canonicalize.c (DOUBLE_SLASH_IS_DISTINCT_ROOT): Provide
fallback definition.
(canonicalize_filename_mode): Use it to protect //.
* lib/canonicalize-lgpl.c (DOUBLE_SLASH_IS_DISTINCT_ROOT)
(__realpath): Likewise.
* tests/test-canonicalize.c (main): Test this.
* tests/test-canonicalize-lgpl.c (main): Likewise.
* modules/canonicalize-tests (Depends-on): Add same-inode.
* modules/canonicalize-lgpl-tests (Depends-on): Likewise.

Signed-off-by: Eric Blake <ebb9@byu.net>
---

diff --git a/ChangeLog b/ChangeLog
index 6121def98..b0464b4ae 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,20 @@
 2009-09-17  Eric Blake  <ebb9@byu.net>
 
+	canonicalize, canonicalize-lgpl: honor // if distinct from /
+	* modules/canonicalize (Files): Add double-slash-root.m4.
+	* modules/canonicalize-lgpl (Files): Likewise.
+	* m4/canonicalize.m4 (gl_FUNC_CANONICALIZE_FILENAME_MODE)
+	(gl_CANONICALIZE_LGPL_SEPARATE): Add dependency.
+	* lib/canonicalize.c (DOUBLE_SLASH_IS_DISTINCT_ROOT): Provide
+	fallback definition.
+	(canonicalize_filename_mode): Use it to protect //.
+	* lib/canonicalize-lgpl.c (DOUBLE_SLASH_IS_DISTINCT_ROOT)
+	(__realpath): Likewise.
+	* tests/test-canonicalize.c (main): Test this.
+	* tests/test-canonicalize-lgpl.c (main): Likewise.
+	* modules/canonicalize-tests (Depends-on): Add same-inode.
+	* modules/canonicalize-lgpl-tests (Depends-on): Likewise.
+
 	canonicalize-lgpl: fix glibc bug with trailing slash
 	* m4/canonicalize-lgpl.m4: Move contents...
 	* m4/canonicalize.m4: ...here.
diff --git a/lib/canonicalize-lgpl.c b/lib/canonicalize-lgpl.c
index fbde01bbc..fa310fb59 100644
--- a/lib/canonicalize-lgpl.c
+++ b/lib/canonicalize-lgpl.c
@@ -67,6 +67,10 @@
 # endif
 #endif
 
+#ifndef DOUBLE_SLASH_IS_DISTINCT_ROOT
+# define DOUBLE_SLASH_IS_DISTINCT_ROOT 0
+#endif
+
 #if !FUNC_REALPATH_WORKS || defined _LIBC
 /* Return the canonical absolute name of file NAME.  A canonical name
    does not contain any `.', `..' components nor any repeated path
@@ -141,6 +145,8 @@ __realpath (const char *name, char *resolved)
     {
       rpath[0] = '/';
       dest = rpath + 1;
+      if (DOUBLE_SLASH_IS_DISTINCT_ROOT && name[1] == '/')
+	*dest++ = '/';
     }
 
   for (start = end = name; *start; start = end)
@@ -169,6 +175,9 @@ __realpath (const char *name, char *resolved)
 	  /* Back up to previous component, ignore if at root already.  */
 	  if (dest > rpath + 1)
 	    while ((--dest)[-1] != '/');
+	  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rpath + 1
+	      && *dest == '/')
+	    dest++;
 	}
       else
 	{
@@ -276,11 +285,21 @@ __realpath (const char *name, char *resolved)
 	      name = end = memcpy (extra_buf, buf, n);
 
 	      if (buf[0] == '/')
-		dest = rpath + 1;	/* It's an absolute symlink */
+		{
+		  dest = rpath + 1;	/* It's an absolute symlink */
+		  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && buf[1] == '/')
+		    *dest++ = '/';
+		}
 	      else
-		/* Back up to previous component, ignore if at root already: */
-		if (dest > rpath + 1)
-		  while ((--dest)[-1] != '/');
+		{
+		  /* Back up to previous component, ignore if at root
+		     already: */
+		  if (dest > rpath + 1)
+		    while ((--dest)[-1] != '/');
+		  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rpath + 1
+		      && *dest == '/')
+		    dest++;
+		}
 	    }
 	  else if (!S_ISDIR (st.st_mode) && *end != '\0')
 	    {
@@ -291,6 +310,8 @@ __realpath (const char *name, char *resolved)
     }
   if (dest > rpath + 1 && dest[-1] == '/')
     --dest;
+  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rpath + 1 && *dest == '/')
+    dest++;
   *dest = '\0';
 
   if (extra_buf)
diff --git a/lib/canonicalize.c b/lib/canonicalize.c
index 3a0154bd0..9434699fd 100644
--- a/lib/canonicalize.c
+++ b/lib/canonicalize.c
@@ -31,6 +31,10 @@
 #include "xalloc.h"
 #include "xgetcwd.h"
 
+#ifndef DOUBLE_SLASH_IS_DISTINCT_ROOT
+# define DOUBLE_SLASH_IS_DISTINCT_ROOT 0
+#endif
+
 #if !((HAVE_CANONICALIZE_FILE_NAME && FUNC_REALPATH_WORKS)	\
       || GNULIB_CANONICALIZE_LGPL)
 /* Return the canonical absolute name of file NAME.  A canonical name
@@ -122,6 +126,8 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
       rname_limit = rname + PATH_MAX;
       rname[0] = '/';
       dest = rname + 1;
+      if (DOUBLE_SLASH_IS_DISTINCT_ROOT && name[1] == '/')
+	*dest++ = '/';
     }
 
   for (start = name; *start; start = end)
@@ -143,6 +149,9 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	  /* Back up to previous component, ignore if at root already.  */
 	  if (dest > rname + 1)
 	    while ((--dest)[-1] != '/');
+	  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
+	      && *dest == '/')
+	    dest++;
 	}
       else
 	{
@@ -226,11 +235,21 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
 	      name = end = memcpy (extra_buf, buf, n);
 
 	      if (buf[0] == '/')
-		dest = rname + 1;	/* It's an absolute symlink */
+		{
+		  dest = rname + 1;	/* It's an absolute symlink */
+		  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && buf[1] == '/')
+		    *dest++ = '/';
+		}
 	      else
-		/* Back up to previous component, ignore if at root already: */
-		if (dest > rname + 1)
-		  while ((--dest)[-1] != '/');
+		{
+		  /* Back up to previous component, ignore if at root
+		     already: */
+		  if (dest > rname + 1)
+		    while ((--dest)[-1] != '/');
+		  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1
+		      && *dest == '/')
+		    dest++;
+		}
 
 	      free (buf);
 	    }
@@ -246,6 +265,8 @@ canonicalize_filename_mode (const char *name, canonicalize_mode_t can_mode)
     }
   if (dest > rname + 1 && dest[-1] == '/')
     --dest;
+  if (DOUBLE_SLASH_IS_DISTINCT_ROOT && dest == rname + 1 && *dest == '/')
+    dest++;
   *dest = '\0';
 
   free (extra_buf);
diff --git a/m4/canonicalize.m4 b/m4/canonicalize.m4
index 47c5c01ad..2d24350e1 100644
--- a/m4/canonicalize.m4
+++ b/m4/canonicalize.m4
@@ -1,4 +1,4 @@
-# canonicalize.m4 serial 15
+# canonicalize.m4 serial 16
 
 dnl Copyright (C) 2003-2007, 2009 Free Software Foundation, Inc.
 
@@ -14,6 +14,7 @@ AC_DEFUN([gl_FUNC_CANONICALIZE_FILENAME_MODE],
 
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
   AC_CHECK_FUNCS_ONCE([canonicalize_file_name])
+  AC_REQUIRE([gl_DOUBLE_SLASH_ROOT])
   AC_REQUIRE([gl_FUNC_REALPATH_WORKS])
   if test $ac_cv_func_canonicalize_file_name = no; then
     HAVE_CANONICALIZE_FILE_NAME=0
@@ -47,6 +48,7 @@ AC_DEFUN([gl_CANONICALIZE_LGPL_SEPARATE],
 [
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
   AC_CHECK_FUNCS_ONCE([canonicalize_file_name getcwd readlink])
+  AC_REQUIRE([gl_DOUBLE_SLASH_ROOT])
   AC_REQUIRE([gl_FUNC_REALPATH_WORKS])
   AC_CHECK_HEADERS_ONCE([sys/param.h])
 ])
diff --git a/modules/canonicalize b/modules/canonicalize
index d039854f1..39a5102e3 100644
--- a/modules/canonicalize
+++ b/modules/canonicalize
@@ -5,6 +5,7 @@ Files:
 lib/canonicalize.h
 lib/canonicalize.c
 m4/canonicalize.m4
+m4/double-slash-root.m4
 
 Depends-on:
 areadlink-with-size
diff --git a/modules/canonicalize-lgpl b/modules/canonicalize-lgpl
index f6b005579..6a748f300 100644
--- a/modules/canonicalize-lgpl
+++ b/modules/canonicalize-lgpl
@@ -4,6 +4,7 @@ realpath, canonical_file_name: Provide canonical absolute file name
 Files:
 lib/canonicalize-lgpl.c
 m4/canonicalize.m4
+m4/double-slash-root.m4
 
 Depends-on:
 alloca-opt
diff --git a/modules/canonicalize-lgpl-tests b/modules/canonicalize-lgpl-tests
index 200950986..cf96c58d5 100644
--- a/modules/canonicalize-lgpl-tests
+++ b/modules/canonicalize-lgpl-tests
@@ -2,6 +2,7 @@ Files:
 tests/test-canonicalize-lgpl.c
 
 Depends-on:
+same-inode
 
 configure.ac:
 AC_CHECK_FUNCS_ONCE([symlink])
diff --git a/modules/canonicalize-tests b/modules/canonicalize-tests
index f91c5f92e..202d639f5 100644
--- a/modules/canonicalize-tests
+++ b/modules/canonicalize-tests
@@ -3,6 +3,7 @@ tests/test-canonicalize.c
 
 Depends-on:
 progname
+same-inode
 
 configure.ac:
 AC_CHECK_FUNCS_ONCE([symlink])
diff --git a/tests/test-canonicalize-lgpl.c b/tests/test-canonicalize-lgpl.c
index f2c4e7a04..39025fa39 100644
--- a/tests/test-canonicalize-lgpl.c
+++ b/tests/test-canonicalize-lgpl.c
@@ -27,6 +27,8 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
+#include "same-inode.h"
+
 #if !HAVE_SYMLINK
 # define symlink(a,b) (-1)
 #endif /* !HAVE_SYMLINK */
@@ -115,6 +117,7 @@ main ()
   ASSERT (symlink ("wum", BASE "/ouk") == 0);
   ASSERT (symlink ("../ise", BASE "/ket") == 0);
   ASSERT (mkdir (BASE "/lum", 0700) == 0);
+  ASSERT (symlink ("//.//../..", BASE "/droot") == 0);
 
   /* Check that the symbolic link to a file can be resolved.  */
   {
@@ -182,7 +185,33 @@ main ()
     ASSERT (errno == ELOOP);
   }
 
+  /* Check that leading // is honored correctly.  */
+  {
+    struct stat st1;
+    struct stat st2;
+    char *result1 = canonicalize_file_name ("//.");
+    char *result2 = canonicalize_file_name (BASE "/droot");
+    ASSERT (result1);
+    ASSERT (result2);
+    ASSERT (stat ("/", &st1) == 0);
+    ASSERT (stat ("//", &st2) == 0);
+    if (SAME_INODE (st1, st2))
+      {
+	ASSERT (strcmp (result1, "/") == 0);
+	ASSERT (strcmp (result2, "/") == 0);
+      }
+    else
+      {
+	ASSERT (strcmp (result1, "//") == 0);
+	ASSERT (strcmp (result2, "//") == 0);
+      }
+    free (result1);
+    free (result2);
+  }
+
+
   /* Cleanup.  */
+  ASSERT (remove (BASE "/droot") == 0);
   ASSERT (remove (BASE "/plo") == 0);
   ASSERT (remove (BASE "/huk") == 0);
   ASSERT (remove (BASE "/bef") == 0);
diff --git a/tests/test-canonicalize.c b/tests/test-canonicalize.c
index 010ca701d..f8dcc54d5 100644
--- a/tests/test-canonicalize.c
+++ b/tests/test-canonicalize.c
@@ -28,6 +28,8 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
+#include "same-inode.h"
+
 #if !HAVE_SYMLINK
 # define symlink(a,b) (-1)
 #endif
@@ -138,6 +140,7 @@ main ()
   ASSERT (mkdir (BASE "/d", 0700) == 0);
   ASSERT (close (creat (BASE "/d/2", 0600)) == 0);
   ASSERT (symlink ("../s/2", BASE "/d/1") == 0);
+  ASSERT (symlink ("//.//../..", BASE "/droot") == 0);
 
   /* Check that the symbolic link to a file can be resolved.  */
   {
@@ -281,7 +284,42 @@ main ()
     free (result2);
   }
 
+  /* Check that leading // is honored correctly.  */
+  {
+    struct stat st1;
+    struct stat st2;
+    char *result1 = canonicalize_file_name ("//.");
+    char *result2 = canonicalize_filename_mode ("//.", CAN_EXISTING);
+    char *result3 = canonicalize_file_name (BASE "/droot");
+    char *result4 = canonicalize_filename_mode (BASE "/droot", CAN_EXISTING);
+    ASSERT (result1);
+    ASSERT (result2);
+    ASSERT (result3);
+    ASSERT (result4);
+    ASSERT (stat ("/", &st1) == 0);
+    ASSERT (stat ("//", &st2) == 0);
+    if (SAME_INODE (st1, st2))
+      {
+        ASSERT (strcmp (result1, "/") == 0);
+        ASSERT (strcmp (result2, "/") == 0);
+        ASSERT (strcmp (result3, "/") == 0);
+        ASSERT (strcmp (result4, "/") == 0);
+      }
+    else
+      {
+        ASSERT (strcmp (result1, "//") == 0);
+        ASSERT (strcmp (result2, "//") == 0);
+        ASSERT (strcmp (result3, "//") == 0);
+        ASSERT (strcmp (result4, "//") == 0);
+      }
+    free (result1);
+    free (result2);
+    free (result3);
+    free (result4);
+  }
+
   /* Cleanup.  */
+  ASSERT (remove (BASE "/droot") == 0);
   ASSERT (remove (BASE "/d/1") == 0);
   ASSERT (remove (BASE "/d/2") == 0);
   ASSERT (remove (BASE "/d") == 0);