[patchv2] Record objfile->original_name as an absolute path

[Jan Kratochvil <jan.kratochvil@redhat.com>]

Hi Doug,

here is an updated+rebased patch.  The testcase is kept as is.

No regressions on {x86_64,x86_64-m32,i686}-fedora21pre-linux-gnu.


Thanks,
Jan


gdb/
2013-09-25  Doug Evans  <dje@google.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	* objfiles.c (allocate_objfile): Save original_name as an absolute
	path.
	* objfiles.h (struct objfile): Expand comment on original_name.
	* source.c (openp): Call gdb_abspath.
	* utils.c (gdb_abspath): New function.
	* utils.h (gdb_abspath): Declare.

gdb/testsuite/
2013-09-25  Doug Evans  <dje@google.com>

	* gdb.dwarf/dwp-symlink.c: Fake out gdb to not load debug info
	at start.
	* gdb.dwarf/dwp-symlink.exp: Test trying to load dwp when the binary
	has been specified with a relative path and we have chdir'd before
	accessing the debug info.

diff --git a/gdb/objfiles.c b/gdb/objfiles.c
index d1f3121..8cc93c5 100644
--- a/gdb/objfiles.c
+++ b/gdb/objfiles.c
@@ -276,6 +276,7 @@ struct objfile *
 allocate_objfile (bfd *abfd, const char *name, int flags)
 {
   struct objfile *objfile;
+  char *expanded_name;
 
   objfile = (struct objfile *) xzalloc (sizeof (struct objfile));
   objfile->psymbol_cache = psymbol_bcache_init ();
@@ -290,10 +291,20 @@ allocate_objfile (bfd *abfd, const char *name, int flags)
     {
       gdb_assert (abfd == NULL);
       gdb_assert ((flags & OBJF_NOT_FILENAME) != 0);
-      name = "<<anonymous objfile>>";
+      expanded_name = xstrdup ("<<anonymous objfile>>");
     }
-  objfile->original_name = obstack_copy0 (&objfile->objfile_obstack, name,
-					  strlen (name));
+  else if ((flags & OBJF_NOT_FILENAME) != 0)
+    expanded_name = xstrdup (name);
+  else
+    expanded_name = gdb_abspath (name);
+  objfile->original_name = obstack_copy0 (&objfile->objfile_obstack,
+					  expanded_name,
+					  strlen (expanded_name));
+  xfree (expanded_name);
+
+  /* Update the per-objfile information that comes from the bfd, ensuring
+     that any data that is reference is saved in the per-objfile data
+     region.  */
 
   /* Update the per-objfile information that comes from the bfd, ensuring
      that any data that is reference is saved in the per-objfile data
diff --git a/gdb/objfiles.h b/gdb/objfiles.h
index 08771d0..9f3d35f 100644
--- a/gdb/objfiles.h
+++ b/gdb/objfiles.h
@@ -212,8 +212,10 @@ struct objfile
 
     struct objfile *next;
 
-    /* The object file's name, tilde-expanded and absolute.  This
-       pointer is never NULL.  This does not have to be freed; it is
+    /* The object file's original name as specified by the user,
+       made absolute, and tilde-expanded.  However, it is not canonicalized
+       (i.e., it has not been passed through gdb_realpath).
+       This pointer is never NULL.  This does not have to be freed; it is
        guaranteed to have a lifetime at least as long as the objfile.  */
 
     char *original_name;
diff --git a/gdb/source.c b/gdb/source.c
index 9fa99b4..b115d79 100644
--- a/gdb/source.c
+++ b/gdb/source.c
@@ -853,28 +853,10 @@ done:
       /* If a file was opened, canonicalize its filename.  */
       if (fd < 0)
 	*filename_opened = NULL;
+      else if ((opts & OPF_RETURN_REALPATH) != 0)
+	*filename_opened = gdb_realpath (filename);
       else
-	{
-	  char *(*realpath_fptr) (const char *);
-
-	  realpath_fptr = ((opts & OPF_RETURN_REALPATH) != 0
-			   ? gdb_realpath : xstrdup);
-
-	  if (IS_ABSOLUTE_PATH (filename))
-	    *filename_opened = realpath_fptr (filename);
-	  else
-	    {
-	      /* Beware the // my son, the Emacs barfs, the botch that catch...  */
-
-	      char *f = concat (current_directory,
-				IS_DIR_SEPARATOR (current_directory[strlen (current_directory) - 1])
-				? "" : SLASH_STRING,
-				filename, (char *)NULL);
-
-	      *filename_opened = realpath_fptr (f);
-	      xfree (f);
-	    }
-	}
+	*filename_opened = gdb_abspath (filename);
     }
 
   return fd;
diff --git a/gdb/testsuite/gdb.dwarf2/dwp-symlink.c b/gdb/testsuite/gdb.dwarf2/dwp-symlink.c
index 5be12fb..a93d5e7 100644
--- a/gdb/testsuite/gdb.dwarf2/dwp-symlink.c
+++ b/gdb/testsuite/gdb.dwarf2/dwp-symlink.c
@@ -15,6 +15,13 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+/* Cheezy hack to prevent set_initial_language from trying to look up main.
+   We do this so that gdb won't try to open the dwp file when the file is
+   first selected.  This gives us a chance to do a chdir before attempting
+   to access the debug info.  */
+asm (".globl main.main");
+asm ("main.main: .byte 0");
+
 int
 main (int argc, char **argv)
 {
diff --git a/gdb/testsuite/gdb.dwarf2/dwp-symlink.exp b/gdb/testsuite/gdb.dwarf2/dwp-symlink.exp
index ad0522b..a0daae4 100644
--- a/gdb/testsuite/gdb.dwarf2/dwp-symlink.exp
+++ b/gdb/testsuite/gdb.dwarf2/dwp-symlink.exp
@@ -75,3 +75,23 @@ gdb_test "ptype main" {type = int \(\)} "binary default, dwp at symlink"
 clean_restart "$thelink"
 
 gdb_test "ptype main" {type = int \(int, char \*\*\)} "binary symlink, dwp at symlink"
+
+# Verify we can still find the dwp if we change directories and we specified
+# a relative path for the program.
+
+set saved_pwd [pwd]
+
+# This is clean_restart, but specifying a relative path to the binary.
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_test "cd [file dirname [standard_output_file ${thelink}]]" \
+    "Working directory .*"
+gdb_load "./${thelink}"
+
+gdb_test "cd .." "Working directory .*"
+
+gdb_test "ptype main" {type = int \(int, char \*\*\)} \
+    "relative path, binary symlink, dwp at symlink"
+
+cd $saved_pwd
diff --git a/gdb/utils.c b/gdb/utils.c
index 26879ec..62d07d6 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -3204,6 +3204,32 @@ gdb_realpath (const char *filename)
   return xstrdup (filename);
 }
 
+/* Return PATH in absolute form, performing tilde-expansion if necessary.
+   PATH cannot be NULL or the empty string.
+   This does not resolve symlinks however, use gdb_realpath for that.
+   Space for the result is allocated with malloc.
+   If the path is already absolute, it is strdup'd.
+   If there is a problem computing the absolute path, the path is returned
+   unchanged (still strdup'd).  */
+
+char *
+gdb_abspath (const char *path)
+{
+  gdb_assert (path != NULL && path[0] != '\0');
+
+  if (path[0] == '~')
+    return tilde_expand (path);
+
+  if (IS_ABSOLUTE_PATH (path))
+    return xstrdup (path);
+
+  /* Beware the // my son, the Emacs barfs, the botch that catch...  */
+  return concat (current_directory,
+	    IS_DIR_SEPARATOR (current_directory[strlen (current_directory) - 1])
+		 ? "" : SLASH_STRING,
+		 path, (char *) NULL);
+}
+
 ULONGEST
 align_up (ULONGEST v, int n)
 {
diff --git a/gdb/utils.h b/gdb/utils.h
index 3492f09..29f79d5 100644
--- a/gdb/utils.h
+++ b/gdb/utils.h
@@ -128,6 +128,8 @@ extern struct cleanup *make_bpstat_clear_actions_cleanup (void);
 
 extern char *gdb_realpath (const char *);
 
+extern char *gdb_abspath (const char *);
+
 extern int gdb_filename_fnmatch (const char *pattern, const char *string,
 				 int flags);