[RFA] Add -s option to source command.

[dje at google dot com (Doug Evans)]

Hi.

In a big source tree with multiple disparate components it's useful to be
able to load scripts without having to type full path names.

This patch adds a -s option to the source command to make it search
for the script in the source search path even if the script name specifies
a directory.
For example, adding the top level source directory to the source search path
lets one load scripts from any component by only typing the path from
the top directory.

I thought of simply extending the source command to do the search anyway
but the current code explicitly doesn't do that to make "./foo" only mean
"foo" in the current directory.  Granted, the comment (see openp) is
referring to executables, but it's not clear to me it shouldn't also
apply to scripts.  Plus, "source /absolute/path" should probably not
scan the search path by default.
So I went with adding an option.

This patch also does a minor reorg of find_and_open_script so that
it's useful in a subsequent patch I'll be submitting.
I think the reorg is useful in itself, e.g. removing the from_tty
arg to find_and_open_script, so I've including it here.

Included are doc and testcase additions.

Ok to check in?

2010-04-06  Doug Evans  <dje@google.com>

	Add -s option to source command.
	* cli/cli-cmds.c (find_and_open_script): Add function comment.
	Delete from_tty and cleanupp args.  Split filep arg into file and
	full_pathp.  New arg search_path.
	(source_script_from_stream): New function.
	(source_script_with_search): New function.
	(source_script): Rewrite.
	(source_command): Parse "-s" option.
	(init_cli_cmds): Add "-s" docs to source command help.
	* python/python.c (source_python_script): Make file arg a const char *.
	Don't call fclose, leave for caller.
	* python/python.h (source_python_script): Update.

	testsuite/
	* gdb.base/source-test.gdb: New file.
	* gdb.base/source.exp: Add tests for "source -v" and "source -s".

	doc/
	* gdb.texinfo (Command Files): Add docs for new "source -s" option.

Index: cli/cli-cmds.c
===================================================================
RCS file: /cvs/src/src/gdb/cli/cli-cmds.c,v
retrieving revision 1.98
diff -u -p -r1.98 cli-cmds.c
--- cli/cli-cmds.c	5 Mar 2010 20:18:15 -0000	1.98
+++ cli/cli-cmds.c	6 Apr 2010 21:23:23 -0000
@@ -470,62 +470,59 @@ Script filename extension recognition is
 		    value);
 }
 
+/* Try to open SCRIPT_FILE.
+   If successful, the full path name is stored in *FULL_PATHP,
+   the stream is stored in *STREAMP, and return 1.
+   The caller is responsible for freeing *FULL_PATHP.
+   If not successful, return 0; errno is set for the last file
+   we tried to open.
+
+   If SEARCH_PATH is non-zero, and the file isn't found in cwd,
+   search for it in the source search path.
+
+   NOTE: This calls openp which uses xfullpath to compute the full path
+   instead of gdb_realpath.  Symbolic links are not resolved.  */
+
 static int
-find_and_open_script (int from_tty, char **filep, FILE **streamp,
-		      struct cleanup **cleanupp)
+find_and_open_script (const char *script_file, int search_path,
+		      FILE **streamp, char **full_pathp)
 {
-  char *file = *filep;
-  char *full_pathname = NULL;
+  char *file;
   int fd;
   struct cleanup *old_cleanups;
+  int search_flags = OPF_TRY_CWD_FIRST;
 
-  file = tilde_expand (file);
+  file = tilde_expand (script_file);
   old_cleanups = make_cleanup (xfree, file);
 
+  if (search_path)
+    search_flags |= OPF_SEARCH_IN_PATH;
+
   /* Search for and open 'file' on the search path used for source
      files.  Put the full location in 'full_pathname'.  */
-  fd = openp (source_path, OPF_TRY_CWD_FIRST,
-	      file, O_RDONLY, &full_pathname);
-  make_cleanup (xfree, full_pathname);
-
-  /* Use the full path name, if it is found.  */
-  if (full_pathname != NULL && fd != -1)
-    {
-      file = full_pathname;
-    }
+  fd = openp (source_path, search_flags,
+	      file, O_RDONLY, full_pathp);
 
   if (fd == -1)
     {
-      if (from_tty)
-	perror_with_name (file);
-      else
-	{
-	  do_cleanups (old_cleanups);
-	  return 0;
-	}
+      int save_errno = errno;
+      do_cleanups (old_cleanups);
+      errno = save_errno;
+      return 0;
     }
 
-  *streamp = fdopen (fd, FOPEN_RT);
-  *filep = file;
-  *cleanupp = old_cleanups;
+  do_cleanups (old_cleanups);
 
+  *streamp = fdopen (fd, FOPEN_RT);
   return 1;
 }
 
-void
-source_script (char *file, int from_tty)
-{
-  FILE *stream;
-  struct cleanup *old_cleanups;
-
-  if (file == NULL || *file == 0)
-    {
-      error (_("source command requires file name of file to source."));
-    }
-
-  if (!find_and_open_script (from_tty, &file, &stream, &old_cleanups))
-    return;
+/* Load script FILE, which has already been opened as STREAM.
+   STREAM is closed before we return.  */
 
+static void
+source_script_from_stream (FILE *stream, const char *file)
+{
   if (script_ext_mode != script_ext_off
       && strlen (file) > 3 && !strcmp (&file[strlen (file) - 3], ".py"))
     {
@@ -541,22 +538,64 @@ source_script (char *file, int from_tty)
 	  if (script_ext_mode == script_ext_soft
 	      && e.reason == RETURN_ERROR && e.error == UNSUPPORTED_ERROR)
 	    {
-	      if (!find_and_open_script (from_tty, &file, &stream, &old_cleanups))
-		return;
-
-	      script_from_file (stream, file);
+	      fseek (stream, 0, SEEK_SET);
+	      script_from_file (stream, (char*) file);
 	    }
 	  else
-	    /* Nope, just punt.  */
-	    throw_exception (e);
+	    {
+	      /* Nope, just punt.  */
+	      fclose (stream);
+	      throw_exception (e);
+	    }
 	}
+      else
+	fclose (stream);
     }
   else
     script_from_file (stream, file);
+}
 
+/* Worker to perform the "source" command.
+   Load script FILE.
+   If SEARCH_PATH is non-zero, and the file isn't found in cwd,
+   search for it in the source search path.  */
+
+static void
+source_script_with_search (const char *file, int from_tty, int search_path)
+{
+  FILE *stream;
+  char *full_path;
+  struct cleanup *old_cleanups;
+
+  if (file == NULL || *file == 0)
+    error (_("source command requires file name of file to source."));
+
+  if (!find_and_open_script (file, search_path, &stream, &full_path))
+    {
+      /* The script wasn't found, or was otherwise inaccessible.
+	 If the source command was invoked interactively, throw an error.
+	 Otherwise (e.g. if it was invoked by a script), silently ignore
+	 the error.  */
+      if (from_tty)
+	perror_with_name (file);
+      else
+	return;
+    }
+
+  old_cleanups = make_cleanup (xfree, full_path);
+  source_script_from_stream (stream, file);
   do_cleanups (old_cleanups);
 }
 
+/* Wrapper around source_script_with_search to export it to main.c
+   for use in loading .gdbinit scripts.  */
+
+void
+source_script (char *file, int from_tty)
+{
+  source_script_with_search (file, from_tty, 0);
+}
+
 /* Return the source_verbose global variable to its previous state
    on exit from the source command, by whatever means.  */
 static void
@@ -572,33 +611,52 @@ source_command (char *args, int from_tty
   struct cleanup *old_cleanups;
   char *file = args;
   int *old_source_verbose = xmalloc (sizeof(int));
+  int search_path = 0;
 
   *old_source_verbose = source_verbose;
   old_cleanups = make_cleanup (source_verbose_cleanup, old_source_verbose);
 
   /* -v causes the source command to run in verbose mode.
+     -s causes the file to be searched in the source search path,
+     even if the file name contains a '/'.
      We still have to be able to handle filenames with spaces in a
      backward compatible way, so buildargv is not appropriate.  */
 
   if (args)
     {
-      /* Make sure leading white space does not break the comparisons.  */
-      while (isspace(args[0]))
-	args++;
-
-      /* Is -v the first thing in the string?  */
-      if (args[0] == '-' && args[1] == 'v' && isspace (args[2]))
+      while (args[0] != '\0')
 	{
-	  source_verbose = 1;
+	  /* Make sure leading white space does not break the comparisons.  */
+	  while (isspace(args[0]))
+	    args++;
+
+	  if (args[0] != '-')
+	    break;
+
+	  if (args[1] == 'v' && isspace (args[2]))
+	    {
+	      source_verbose = 1;
+
+	      /* Skip passed -v.  */
+	      args = &args[3];
+	    }
+	  else if (args[1] == 's' && isspace (args[2]))
+	    {
+	      search_path = 1;
 
-	  /* Trim -v and whitespace from the filename.  */
-	  file = &args[3];
-	  while (isspace (file[0]))
-	    file++;
+	      /* Skip passed -s.  */
+	      args = &args[3];
+	    }
+	  else
+	    break;
 	}
+
+      while (isspace (args[0]))
+	args++;
+      file = args;
     }
 
-  source_script (file, from_tty);
+  source_script_with_search (file, from_tty, search_path);
 }
 
 
@@ -1379,6 +1437,8 @@ Commands defined in this way may have up
 Read commands from a file named FILE.\n\
 Optional -v switch (before the filename) causes each command in\n\
 FILE to be echoed as it is executed.\n\
+Optional -s switch (before the filename) causes gdb to search for\n\
+the script in the source search path, even if FILE contains directories.\n\
 Note that the file \"%s\" is read automatically in this way\n\
 when GDB is started."), gdbinit);
   c = add_cmd ("source", class_support, source_command,
Index: python/python.c
===================================================================
RCS file: /cvs/src/src/gdb/python/python.c,v
retrieving revision 1.27
diff -u -p -r1.27 python.c
--- python/python.c	5 Mar 2010 20:18:17 -0000	1.27
+++ python/python.c	6 Apr 2010 21:23:24 -0000
@@ -362,10 +362,11 @@ gdbpy_parse_and_eval (PyObject *self, Py
 }
 
 /* Read a file as Python code.  STREAM is the input file; FILE is the
-   name of the file.  */
+   name of the file.
+   STREAM is not closed, that is the caller's responsibility.  */
 
 void
-source_python_script (FILE *stream, char *file)
+source_python_script (FILE *stream, const char *file)
 {
   PyGILState_STATE state;
 
@@ -373,7 +374,6 @@ source_python_script (FILE *stream, char
 
   PyRun_SimpleFile (stream, file);
 
-  fclose (stream);
   PyGILState_Release (state);
 }
 
@@ -560,9 +560,8 @@ eval_python_from_control_command (struct
 }
 
 void
-source_python_script (FILE *stream, char *file)
+source_python_script (FILE *stream, const char *file)
 {
-  fclose (stream);
   throw_error (UNSUPPORTED_ERROR,
 	       _("Python scripting is not supported in this copy of GDB."));
 }
Index: python/python.h
===================================================================
RCS file: /cvs/src/src/gdb/python/python.h,v
retrieving revision 1.7
diff -u -p -r1.7 python.h
--- python/python.h	18 Jan 2010 06:25:22 -0000	1.7
+++ python/python.h	6 Apr 2010 21:23:24 -0000
@@ -24,7 +24,7 @@
 
 void eval_python_from_control_command (struct command_line *);
 
-void source_python_script (FILE *stream, char *file);
+void source_python_script (FILE *stream, const char *file);
 
 int apply_val_pretty_printer (struct type *type, const gdb_byte *valaddr,
 			      int embedded_offset, CORE_ADDR address,
Index: testsuite/gdb.base/source-test.gdb
===================================================================
RCS file: testsuite/gdb.base/source-test.gdb
diff -N testsuite/gdb.base/source-test.gdb
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.base/source-test.gdb	6 Apr 2010 21:23:24 -0000
@@ -0,0 +1,20 @@
+# This testcase is part of GDB, the GNU debugger.
+
+# Copyright 2010 Free Software Foundation, Inc.
+
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# Test GDB's "source -v" and "source -s" commands.
+
+echo test source options\n
Index: testsuite/gdb.base/source.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/source.exp,v
retrieving revision 1.9
diff -u -p -r1.9 source.exp
--- testsuite/gdb.base/source.exp	7 Jan 2010 20:07:18 -0000	1.9
+++ testsuite/gdb.base/source.exp	6 Apr 2010 21:23:24 -0000
@@ -34,5 +34,14 @@ gdb_start
 gdb_test "source ${srcdir}/${subdir}/source-error.gdb" \
     "source-error.gdb:21: Error in sourced command file:\[\r\n\]*Cannot access memory at address 0x0.*" \
     "script contains error"
+
+gdb_test "source -v ${srcdir}/${subdir}/source-test.gdb" \
+    "echo test source options.*" \
+    "source -v"
+
+gdb_test "dir ${srcdir}/${subdir}" ""
+gdb_test "source -s ./source-test.gdb" \
+    "test source options" \
+    "source -s"
     
 gdb_exit
Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.696
diff -u -p -r1.696 gdb.texinfo
--- doc/gdb.texinfo	5 Apr 2010 17:14:57 -0000	1.696
+++ doc/gdb.texinfo	6 Apr 2010 21:28:53 -0000
@@ -19373,7 +19373,7 @@ using the @code{script-extension} settin
 @table @code
 @kindex source
 @cindex execute commands from a file
-@item source [@code{-v}] @var{filename}
+@item source [@code{-s}] [@code{-v}] @var{filename}
 Execute the command file @var{filename}.
 @end table
 
@@ -19390,6 +19390,9 @@ directory, then @value{GDBN} also looks 
 except that @file{$cdir} is not searched because the compilation directory
 is not relevant to scripts.
 
+If @code{-s} is specified, then @value{GDBN} searches for @var{filename}
+on the search path even if @var{filename} specifies a directory.
+
 If @code{-v}, for verbose mode, is given then @value{GDBN} displays
 each command as it is executed.  The option must be given before
 @var{filename}, and is interpreted as part of the filename anywhere else.