RFC: "set logging"

[Daniel Jacobowitz <drow at mvista dot com>]

As discussed earlier:
  set logging on [FILE]
  set logging off
  set logging overwrite [I changed the default to append]
  set logging redirect
  set logging file
  show logging

I decided that one-off command logging was really a different class of thing
from this patch, which is straight output logging, not really script-useful
redirection.  So that's gone.

Is this OK?  Any comments?  Docs OK?

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

2003-06-22  Daniel Jacobowitz  <drow@mvista.com>

	* cli-out.c (struct ui_out_data): Add original_stream.
	(cli_redirect): New function.
	(cli_ui_out_impl): Add cli_redirect.
	(cli_out_new): Initialize original_stream.
	* ui-out.c (default_ui_out_impl): Add NULL for redirect member.
	(uo_redirect, ui_out_redirect): New.
	* ui-out.h (struct ui_out_impl): Add redirect member.
	(redirect_ftype): New.
	(ui_out_redirect): Add prototype.
	* top.c (handle_redirections, pop_output_files): New functions.
	(set_logging_help, set_logging_command, show_logging_command): New
	functions.
	(init_main): Create "set logging" and "show logging" commands.

2003-06-22  Daniel Jacobowitz  <drow@mvista.com>

	* mi-out.c (mi_ui_out_impl): Add NULL for redirect member.

2003-06-22  Daniel Jacobowitz  <drow@mvista.com>

	* tui-out.c (tui_ui_out_impl): Add NULL for redirect member.

2003-06-22  Daniel Jacobowitz  <drow@mvista.com>

	* gdb.texinfo (Logging output): New chapter.

Index: cli-out.c
===================================================================
RCS file: /cvs/src/src/gdb/cli-out.c,v
retrieving revision 1.16
diff -u -p -r1.16 cli-out.c
--- cli-out.c	8 Mar 2003 20:04:27 -0000	1.16
+++ cli-out.c	22 Jun 2003 20:47:08 -0000
@@ -31,6 +31,7 @@
 struct ui_out_data
   {
     struct ui_file *stream;
+    struct ui_file *original_stream;
     int suppress_output;
   };
 typedef struct ui_out_data cli_out_data;
@@ -64,6 +65,7 @@ static void cli_message (struct ui_out *
 			 const char *format, va_list args);
 static void cli_wrap_hint (struct ui_out *uiout, char *identstring);
 static void cli_flush (struct ui_out *uiout);
+static int cli_redirect (struct ui_out *uiout, struct ui_file *outstream);
 
 /* This is the CLI ui-out implementation functions vector */
 
@@ -87,6 +89,7 @@ static struct ui_out_impl cli_ui_out_imp
   cli_message,
   cli_wrap_hint,
   cli_flush,
+  cli_redirect,
   0, /* Does not need MI hacks (i.e. needs CLI hacks).  */
 };
 
@@ -324,6 +327,24 @@ cli_flush (struct ui_out *uiout)
   gdb_flush (data->stream);
 }
 
+int
+cli_redirect (struct ui_out *uiout, struct ui_file *outstream)
+{
+  struct ui_out_data *data = ui_out_data (uiout);
+  if (outstream != NULL)
+    {
+      data->original_stream = data->stream;
+      data->stream = outstream;
+    }
+  else if (data->original_stream != NULL)
+    {
+      data->stream = data->original_stream;
+      data->original_stream = NULL;
+    }
+
+  return 0;
+}
+
 /* local functions */
 
 /* Like cli_field_fmt, but takes a variable number of args
@@ -362,6 +383,7 @@ cli_out_new (struct ui_file *stream)
 
   cli_out_data *data = XMALLOC (cli_out_data);
   data->stream = stream;
+  data->original_stream = NULL;
   data->suppress_output = 0;
   return ui_out_new (&cli_ui_out_impl, data, flags);
 }
Index: top.c
===================================================================
RCS file: /cvs/src/src/gdb/top.c,v
retrieving revision 1.73
diff -u -p -r1.73 top.c
--- top.c	8 Jun 2003 18:27:14 -0000	1.73
+++ top.c	22 Jun 2003 20:47:09 -0000
@@ -1746,6 +1746,224 @@ dont_repeat_command (char *ignored, int 
 				   necessarily reading from stdin.  */
 }
 
+/* Functions and variables for gdb output redirection.  */
+
+/* These hold the pushed copies of the gdb output files.
+   If NULL then nothing has yet been pushed.  */
+static struct ui_file *saved_stdout;
+static struct ui_file *saved_stderr;
+static struct ui_file *saved_stdlog;
+static struct ui_file *saved_stdtarg;
+static char *saved_filename;
+
+static char *logging_filename;
+int logging_overwrite, logging_redirect;
+
+/* If we've pushed output files, close them and pop them.  */
+static void
+pop_output_files ()
+{
+  /* Only delete one of the files -- they are all set to the same
+     value.  */
+  ui_file_delete (gdb_stdout);
+  gdb_stdout = saved_stdout;
+  gdb_stderr = saved_stderr;
+  gdb_stdlog = saved_stdlog;
+  gdb_stdtarg = saved_stdtarg;
+  saved_stdout = NULL;
+  saved_stderr = NULL;
+  saved_stdlog = NULL;
+  saved_stdtarg = NULL;
+
+  ui_out_redirect (uiout, NULL);
+}
+
+/* This is a helper for the `set logging' command.  */
+static void
+handle_redirections (int from_tty)
+{
+  struct ui_file *output;
+
+  if (saved_filename != NULL)
+    {
+      fprintf_unfiltered (gdb_stdout, "Already logging to %s.\n",
+			  saved_filename);
+      return;
+    }
+
+  output = gdb_fopen (logging_filename, logging_overwrite ? "w" : "a");
+  if (output == NULL)
+    perror_with_name ("set logging");
+
+  /* Redirects everything to gdb_stdout while this is running.  */
+  if (!logging_redirect)
+    {
+      output = tee_file_new (gdb_stdout, 0, output, 1);
+      if (output == NULL)
+	perror_with_name ("set logging");
+      if (from_tty)
+	fprintf_unfiltered (gdb_stdout, "Copying output to %s.\n",
+			    logging_filename);
+    }
+  else if (from_tty)
+    fprintf_unfiltered (gdb_stdout, "Redirecting output to %s.\n",
+			logging_filename);
+
+  saved_filename = xstrdup (logging_filename);
+  saved_stdout = gdb_stdout;
+  saved_stderr = gdb_stderr;
+  saved_stdlog = gdb_stdlog;
+  saved_stdtarg = gdb_stdtarg;
+
+  gdb_stdout = output;
+  gdb_stderr = output;
+  gdb_stdlog = output;
+  gdb_stdtarg = output;
+
+  if (ui_out_redirect (uiout, gdb_stdout) < 0)
+    warning ("Current output protocol does not support redirection");
+}
+
+static void
+set_logging_help ()
+{
+  printf_unfiltered ("Usage: set logging on [FILENAME]\n");
+  printf_unfiltered ("       set logging off\n");
+  printf_unfiltered ("       set logging FILENAME\n");
+  printf_unfiltered ("       set logging overwrite [on|off]\n");
+  printf_unfiltered ("       set logging append [on|off]\n");
+}
+
+static void
+set_logging_command (char *args, int from_tty)
+{
+  char *first_word, *rest;
+
+  if (args == NULL)
+    {
+      set_logging_help ();
+      return;
+    }
+
+  /* Find the first word and the rest of the line.  */
+  first_word = args;
+  rest = first_word;
+  while (*rest && !isspace (*rest))
+    rest++;
+  if (*rest)
+    {
+      *rest = '\0';
+      rest++;
+      while (*rest && isspace (*rest))
+	rest++;
+    }
+  if (*rest == '\0')
+    rest = NULL;
+
+  if (strcmp (first_word, "off") == 0)
+    {
+      if (rest)
+	{
+	  set_logging_help ();
+	  return;
+	}
+
+      if (saved_filename == NULL)
+	return;
+
+      pop_output_files ();
+      if (from_tty)
+	fprintf_unfiltered (gdb_stdout, "Done logging to %s.\n", saved_filename);
+      xfree (saved_filename);
+      saved_filename = NULL;
+      return;
+    }
+
+  if (strcmp (first_word, "on") == 0)
+    {
+      if (rest)
+	{
+	  xfree (logging_filename);
+	  logging_filename = xstrdup (rest);
+	}
+      if (!logging_filename)
+	logging_filename = xstrdup ("gdb.txt");
+
+      handle_redirections (from_tty);
+      return;
+    }
+
+  if (strcmp (first_word, "file") == 0)
+    {
+      if (rest == NULL)
+	{
+	  set_logging_help ();
+	  return;
+	}
+
+      if (logging_filename)
+	xfree (logging_filename);
+      logging_filename = xstrdup (rest);
+      return;
+    }
+
+  if (strcmp (first_word, "overwrite") == 0)
+    {
+      if (rest == NULL
+	  || strcmp (rest, "1") == 0
+	  || strcmp (rest, "true") == 0
+	  || strcmp (rest, "on") == 0)
+	logging_overwrite = 1;
+      else if (strcmp (rest, "0") == 0
+	       || strcmp (rest, "false") == 0
+	       || strcmp (rest, "off") == 0)
+	logging_overwrite = 0;
+      else
+	set_logging_help ();
+      return;
+    }
+
+  if (strcmp (first_word, "redirect") == 0)
+    {
+      if (rest == NULL
+	  || strcmp (rest, "1") == 0
+	  || strcmp (rest, "true") == 0
+	  || strcmp (rest, "on") == 0)
+	logging_redirect = 1;
+      else if (strcmp (rest, "0") == 0
+	       || strcmp (rest, "false") == 0
+	       || strcmp (rest, "off") == 0)
+	logging_redirect = 0;
+      else
+	set_logging_help ();
+      return;
+    }
+
+  set_logging_help ();
+  return;
+}
+
+void
+show_logging_command (char *args, int from_tty)
+{
+  if (saved_filename)
+    printf_unfiltered ("Currently logging to %s.\n", saved_filename);
+  if (logging_filename == NULL || saved_filename == NULL
+      || strcmp (logging_filename, saved_filename) != 0)
+    printf_unfiltered ("Future logs will be written to %s.\n",
+		       logging_filename ? logging_filename : "gdb.txt");
+
+  if (logging_overwrite)
+    printf_unfiltered ("Logs will overwrite the log file.\n");
+  else
+    printf_unfiltered ("Logs will be appended to the log file.\n");
+
+  if (logging_redirect)
+    printf_unfiltered ("Output will be sent only to the log file.\n");
+  else
+    printf_unfiltered ("Output will be logged and displayed.\n");
+}
+
 /* Functions to manipulate command line editing control variables.  */
 
 /* Number of commands to print in each call to show_commands.  */
@@ -2080,6 +2298,11 @@ ie. the number of previous commands to k
 Use \"on\" to enable the notification, and \"off\" to disable it.", &setlist),
 	 &showlist);
     }
+
+  add_cmd ("logging", no_class, set_logging_command,
+	   "Set logging options", &setlist);
+  add_cmd ("logging", no_class, show_logging_command,
+	   "Show logging options", &showlist);
 }
 
 void
Index: ui-out.c
===================================================================
RCS file: /cvs/src/src/gdb/ui-out.c,v
retrieving revision 1.27
diff -u -p -r1.27 ui-out.c
--- ui-out.c	8 Jun 2003 18:27:14 -0000	1.27
+++ ui-out.c	22 Jun 2003 20:47:09 -0000
@@ -206,6 +206,7 @@ struct ui_out_impl default_ui_out_impl =
   default_message,
   default_wrap_hint,
   default_flush,
+  NULL,
   0, /* Does not need MI hacks.  */
 };
 
@@ -254,6 +255,7 @@ static void uo_message (struct ui_out *u
 			const char *format, va_list args);
 static void uo_wrap_hint (struct ui_out *uiout, char *identstring);
 static void uo_flush (struct ui_out *uiout);
+static int uo_redirect (struct ui_out *uiout, struct ui_file *outstream);
 
 /* Prototypes for local functions */
 
@@ -638,6 +640,12 @@ ui_out_flush (struct ui_out *uiout)
   uo_flush (uiout);
 }
 
+int
+ui_out_redirect (struct ui_out *uiout, struct ui_file *outstream)
+{
+  return uo_redirect (uiout, outstream);
+}
+
 /* set the flags specified by the mask given */
 int
 ui_out_set_flags (struct ui_out *uiout, int mask)
@@ -979,6 +987,15 @@ uo_flush (struct ui_out *uiout)
   if (!uiout->impl->flush)
     return;
   uiout->impl->flush (uiout);
+}
+
+int
+uo_redirect (struct ui_out *uiout, struct ui_file *outstream)
+{
+  if (!uiout->impl->redirect)
+    return -1;
+  uiout->impl->redirect (uiout, outstream);
+  return 0;
 }
 
 /* local functions */
Index: ui-out.h
===================================================================
RCS file: /cvs/src/src/gdb/ui-out.h,v
retrieving revision 1.17
diff -u -p -r1.17 ui-out.h
--- ui-out.h	3 Feb 2003 01:18:37 -0000	1.17
+++ ui-out.h	22 Jun 2003 20:47:09 -0000
@@ -231,6 +231,8 @@ typedef void (message_ftype) (struct ui_
 			      const char *format, va_list args);
 typedef void (wrap_hint_ftype) (struct ui_out * uiout, char *identstring);
 typedef void (flush_ftype) (struct ui_out * uiout);
+typedef int (redirect_ftype) (struct ui_out * uiout,
+			      struct ui_file * outstream);
 
 /* ui-out-impl */
 
@@ -254,6 +256,7 @@ struct ui_out_impl
     message_ftype *message;
     wrap_hint_ftype *wrap_hint;
     flush_ftype *flush;
+    redirect_ftype *redirect;
     int is_mi_like_p;
   };
 
@@ -265,5 +268,9 @@ extern struct ui_out_data *ui_out_data (
 extern struct ui_out *ui_out_new (struct ui_out_impl *impl,
 				  struct ui_out_data *data,
 				  int flags);
+
+/* Redirect the ouptut of a ui_out object temporarily.  */
+
+extern int ui_out_redirect (struct ui_out *uiout, struct ui_file *outstream);
 
 #endif /* UI_OUT_H */
Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.166
diff -u -p -r1.166 gdb.texinfo
--- doc/gdb.texinfo	22 Jun 2003 04:27:24 -0000	1.166
+++ doc/gdb.texinfo	22 Jun 2003 20:47:13 -0000
@@ -757,6 +757,7 @@ type @kbd{quit} or @kbd{C-d} to exit.
 * Invoking GDB::                How to start @value{GDBN}
 * Quitting GDB::                How to quit @value{GDBN}
 * Shell Commands::              How to use shell commands inside @value{GDBN}
+* Logging output::              How to log @value{GDBN}'s output to a file
 @end menu
 
 @node Invoking GDB
@@ -1208,6 +1209,32 @@ You do not have to use the @code{shell} 
 @item make @var{make-args}
 Execute the @code{make} program with the specified
 arguments.  This is equivalent to @samp{shell make @var{make-args}}.
+@end table
+
+@node Logging output
+@section Logging output
+
+You may want to save the output of @value{GDBN} commands to a file.
+There are several commands to control @value{GDBN}'s logging.
+
+@table @code
+@kindex set logging
+@item set logging on [@var{file}]
+Enable logging.  If @var{file} is specified, then the current logfile will be
+changed to @var{file}.
+@item set logging off
+Disable logging.
+@item set logging file @var{file}
+Change the name of the current logfile.  The default logfile is @file{gdb.txt}.
+@item set logging overwrite [on|off]
+By default, @value{GDBN} will append to the logfile.  Set @code{overwrite} if
+you want @code{set logging on} to overwrite the logfile instead.
+@item set logging redirect [on|off]
+By default, @value{GDBN} output will go to both the terminal and the logfile.
+Set @code{redirect} if you want output to go only to the log file.
+@kindex show logging
+@item show logging
+Show the current values of the logging settings.
 @end table
 
 @node Commands
Index: mi/mi-out.c
===================================================================
RCS file: /cvs/src/src/gdb/mi/mi-out.c,v
retrieving revision 1.26
diff -u -p -r1.26 mi-out.c
--- mi/mi-out.c	8 Mar 2003 20:04:27 -0000	1.26
+++ mi/mi-out.c	22 Jun 2003 20:47:13 -0000
@@ -86,6 +86,7 @@ struct ui_out_impl mi_ui_out_impl =
   mi_message,
   mi_wrap_hint,
   mi_flush,
+  NULL,
   1, /* Needs MI hacks.  */
 };
 
Index: tui/tui-out.c
===================================================================
RCS file: /cvs/src/src/gdb/tui/tui-out.c,v
retrieving revision 1.5
diff -u -p -r1.5 tui-out.c
--- tui/tui-out.c	13 Mar 2003 20:24:06 -0000	1.5
+++ tui/tui-out.c	22 Jun 2003 20:47:13 -0000
@@ -90,6 +90,7 @@ static struct ui_out_impl tui_ui_out_imp
   tui_message,
   tui_wrap_hint,
   tui_flush,
+  NULL,
   0, /* Does not need MI hacks (i.e. needs CLI hacks).  */
 };