[PATCH v2 3/3] GDBServer: add 'monitor set server-output' command

[Cleber Rosa <crosa@redhat.com>]

This monitor command, just like the command line option --server-output,
will redirect all of the gdbserver's own output (always sent to stderr)
to a separate file.

gdb/Changelog:
2015-03-25  Cleber Rosa  <crosa@redhat.com>

	* NEWS: New feature in the GDBserver: monitor set server-output.

gdb/doc/Changelog:
2015-03-25  Cleber Rosa  <crosa@redhat.com>

	* gdb.texinfo (info): Add documentation about the 'monitor set
	server-output' command.

gdb/gdbserver/Changelog:
2015-03-25  Cleber Rosa  <crosa@redhat.com>

	* server.c (monitor_show_help): Add help message about the
	'monitor set server-output' command.
	(handle_monitor_command): Respond to 'set server-output' command.

gdb/testsuite/ChangeLog:
2015-03-25  Cleber Rosa  <crosa@redhat.com>

	* gdb.server/server-mon.exp: Add tests with the 'monitor set
	server-output' command succeeding and failing.
---
 gdb/NEWS                                |  2 ++
 gdb/doc/gdb.texinfo                     |  3 +++
 gdb/gdbserver/server.c                  | 24 +++++++++++++++++++++---
 gdb/testsuite/gdb.server/server-mon.exp |  8 ++++++++
 4 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index 22044c2..d8e74bb 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -100,6 +100,8 @@ Itanium running HP-UX         ia64-*-hpux*
 
   ** New option --server-output=file allows users to send the
      server output to a separate file.
+  ** New monitor command "monitor set server-output", the monitor
+     command counterpart of command line option --server-output.
 
 *** Changes in GDB 7.9
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 454f51f..b3442b1 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -19321,6 +19321,9 @@ Include a timestamp in each line of debugging output.
 Options are processed in order.  Thus, for example, if @option{none}
 appears last then no additional information is added to debugging output.
 
+@item monitor set server-output @var{output_filename}
+Redirect the server output to a file given by @var{output_filename}.
+
 @item monitor set libthread-db-search-path [PATH]
 @cindex gdbserver, search path for @code{libthread_db}
 When this command is issued, @var{path} is a colon-separated list of
diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c
index b4a715f..51251f9 100644
--- a/gdb/gdbserver/server.c
+++ b/gdb/gdbserver/server.c
@@ -754,9 +754,9 @@ monitor_show_help (void)
   monitor_output ("    Enable remote protocol debugging messages\n");
   monitor_output ("  set debug-format option1[,option2,...]\n");
   monitor_output ("    Add additional information to debugging messages\n");
-  monitor_output ("    Options: all, none");
-  monitor_output (", timestamp");
-  monitor_output ("\n");
+  monitor_output ("    Options: all, none, timestamp\n");
+  monitor_output ("  set server-output output_filename\n");
+  monitor_output ("    Redirects the server output to output_filename\n");
   monitor_output ("  exit\n");
   monitor_output ("    Quit GDBserver\n");
 }
@@ -1105,6 +1105,24 @@ handle_monitor_command (char *mon, char *own_buf)
 	  xfree (error_msg);
 	}
     }
+  else if (strncmp (mon, "set server-output ",
+		    sizeof ("set server-output ") -1) == 0)
+    {
+      char *out_filename = mon + (sizeof ("set server-output ") - 1);
+      if (set_server_output (out_filename) == 0) {
+	char *monitor_msg = xstrprintf ("Redirected server output to '%s'\n",
+					out_filename);
+	monitor_output (monitor_msg);
+	xfree (monitor_msg);
+      }
+      else
+	{
+	  char *monitor_msg = xstrprintf ("Failed to set server output to '%s'\n",
+					  out_filename);
+	  monitor_output (monitor_msg);
+	  xfree (monitor_msg);
+	}
+    }
   else if (strcmp (mon, "help") == 0)
     monitor_show_help ();
   else if (strcmp (mon, "exit") == 0)
diff --git a/gdb/testsuite/gdb.server/server-mon.exp b/gdb/testsuite/gdb.server/server-mon.exp
index a4c03ee..a19bc11 100644
--- a/gdb/testsuite/gdb.server/server-mon.exp
+++ b/gdb/testsuite/gdb.server/server-mon.exp
@@ -54,3 +54,11 @@ gdb_test "monitor set debug-format all" \
     "All extra debug format options enabled\\."
 gdb_test "monitor set debug-format none" \
     "All extra debug format options disabled\\."
+
+# Tests the monitor command that sends stderr output to another file
+gdb_test "monitor set server-output /dev/null" \
+    "Redirected server output to '/dev/null'"
+
+# Tests the monitor command that sends stderr output to another file
+gdb_test "monitor set server-output /im/pro/ba/ble/pa/th" \
+    "Failed to set server output to '/im/pro/ba/ble/pa/th'"
-- 
1.9.3