[pushed] [gdb/cli] Add command: show logging active

[Tom de Vries <tdevries@suse.de>]

Currently, there's no gdb command that shows whether logging is enabled or
disabled.

There's the show logging command, but output is identical in both cases.
With logging disabled, we have:
...
(gdb) set logging off
(gdb) show logging
logging debugredirect:  The logging output mode is off.
logging file:  The current logfile is "gdb.txt".
logging overwrite: \
  Whether logging overwrites or appends to the log file is off.
logging redirect:  The logging output mode is off.
...
and with logging enabled we have:
...
(gdb) set logging on
Copying output to gdb.txt.
Copying debug output to gdb.txt.
(gdb) show logging
logging debugredirect:  The logging output mode is off.
logging file:  The current logfile is "gdb.txt".
logging overwrite: \
  Whether logging overwrites or appends to the log file is off.
logging redirect:  The logging output mode is off.
...

Add a "show logging active" command, such that we have:
...
(gdb) show logging
logging active:  Logging is disabled.
logging debugredirect:  The logging output mode is off.
logging file:  The current logfile is "gdb.txt".
logging overwrite: \
  Whether logging overwrites or appends to the log file is off.
logging redirect:  The logging output mode is off.
...

Mention the new command in NEWS and docs.

Tested on x86_64-linux.
---
 gdb/NEWS              |  5 +++++
 gdb/cli/cli-logging.c | 13 +++++++++++++
 gdb/doc/gdb.texinfo   |  2 ++
 3 files changed, 20 insertions(+)

diff --git a/gdb/NEWS b/gdb/NEWS
index 9e950d2f80d..253070a2a57 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -32,6 +32,11 @@ maint show internal-warning backtrace
   internal-error, or an internal-warning.  This is on by default for
   internal-error and off by default for internal-warning.
 
+show logging active
+  This command shows whether logging is enabled or disabled.  Whether logging
+  is enabled or disabled is controlled by pre-existing command
+  "set logging [on|off]".
+
 * Python API
 
   ** New function gdb.add_history(), which takes a gdb.Value object
diff --git a/gdb/cli/cli-logging.c b/gdb/cli/cli-logging.c
index f0ee09180f9..081afcc4ca2 100644
--- a/gdb/cli/cli-logging.c
+++ b/gdb/cli/cli-logging.c
@@ -163,6 +163,17 @@ set_logging_off (const char *args, int from_tty)
   saved_filename = NULL;
 }
 
+/* Show the status set by set_logging_on / set_logging_off.  */
+
+static void
+show_logging_on_off (const char *args, int from_tty)
+{
+  if (saved_filename)
+    printf_unfiltered (_("Logging is enabled.\n"));
+  else
+    printf_unfiltered (_("Logging is disabled.\n"));
+}
+
 void _initialize_cli_logging ();
 void
 _initialize_cli_logging ()
@@ -211,4 +222,6 @@ The logfile is used when directing GDB's output."),
 	   _("Enable logging."), &set_logging_cmdlist);
   add_cmd ("off", class_support, set_logging_off,
 	   _("Disable logging."), &set_logging_cmdlist);
+  add_cmd ("active", class_support, show_logging_on_off,
+	   _("Show whether logging is active."), &show_logging_cmdlist);
 }
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 1b13973cdc5..4bea8f9b3dc 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -1723,6 +1723,8 @@ Set @code{redirect} if you want output to go only to the log file.
 By default, @value{GDBN} debug output will go to both the terminal and the logfile.
 Set @code{debugredirect} if you want debug output to go only to the log file.
 @kindex show logging
+@item show logging [active|file|overwrite|redirect|debugredirect]
+Show the current value of the logging setting.
 @item show logging
 Show the current values of the logging settings.
 @end table

base-commit: 0c3e266dc283a45a23185be3bb49e4d33987a892
-- 
2.26.2