Make the default log handler more useful

We make the default log handler only print default and informational
messages if the log domain is explicitly requested.

https://bugzilla.gnome.org/show_bug.cgi?id=661926
This commit is contained in:
Matthias Clasen 2011-11-03 01:48:54 -04:00
parent 7456b43c3e
commit d2d62ecfcd
3 changed files with 92 additions and 2 deletions

View File

@ -54,7 +54,39 @@ variables like <envar>LANG</envar>, <envar>PATH</envar> or <envar>HOME</envar>.
<para>
A list of log levels for which messages should be prefixed by the
program name and PID of the application. The default is to prefix
everything except <literal>G_LOG_LEVEL_MESSAGE</literal> and <literal>G_LOG_LEVEL_INFO</literal>.
everything except <literal>G_LOG_LEVEL_MESSAGE</literal> and
<literal>G_LOG_LEVEL_INFO</literal>.
The possible values are
<literal>error</literal>,
<literal>warning</literal>,
<literal>critical</literal>,
<literal>message</literal>,
<literal>info</literal> and
<literal>debug</literal>.
You can also use the special values
<literal>all</literal> and
<literal>help</literal>.
</para>
<para>
This environment variable only affects the GLib log handler,
g_log_default_handler().
</para>
</formalpara>
<formalpara id="G_MESSAGES_DEBUG">
<title><envar>G_MESSAGES_DEBUG</envar></title>
<para>
A space-separated list of log domains for which informational
and debug messages should be printed. By default, these
messages are not printed.
</para>
<para>
You can also use the special value <literal>all</literal>.
</para>
<para>
This environment variable only affects the GLib log handler,
g_log_default_handler().
</para>
</formalpara>

View File

@ -65,6 +65,7 @@
#include "gbacktrace.h"
#include "gcharset.h"
#include "gconvert.h"
#include "genviron.h"
#include "gmem.h"
#include "gprintfint.h"
#include "gtestutils.h"
@ -969,6 +970,11 @@ format_unsigned (gchar *buf,
#define ALERT_LEVELS (G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL | G_LOG_LEVEL_WARNING)
/* these are emitted by the default log handler */
#define DEFAULT_LEVELS (G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL | G_LOG_LEVEL_WARNING | G_LOG_LEVEL_MESSAGE)
/* these are filtered by G_MESSAGES_DEBUG by the default log handler */
#define INFO_LEVELS (G_LOG_LEVEL_INFO | G_LOG_LEVEL_DEBUG)
static int
mklevel_prefix (gchar level_prefix[STRING_BUFFER_SIZE],
GLogLevelFlags log_level)
@ -1143,6 +1149,26 @@ escape_string (GString *string)
* domain and log level combination. It outputs the message to stderr
* or stdout and if the log level is fatal it calls abort().
*
* The behavior of this log handler can be influenced by a number of
* environment variables:
* <variablelist>
* <varlistentry>
* <term><envar>G_MESSAGES_PREFIXED</envar></term>
* <listitem>
* A :-separated list of log levels for which messages should
* be prefixed by the program name and PID of the aplication.
* </listitem>
* </varlistentry>
* <varlistentry>
* <term><envar>G_MESSAGES_DEBUG</envar></term>
* <listitem>
* A space-separated list of log domains for which debug and
* informational messages are printed. By default these
* messages are not printed.
* </listitem>
* </varlistentry>
* </variablelist>
*
* stderr is used for levels %G_LOG_LEVEL_ERROR, %G_LOG_LEVEL_CRITICAL,
* %G_LOG_LEVEL_WARNING and %G_LOG_LEVEL_MESSAGE. stdout is used for
* the rest.
@ -1156,7 +1182,18 @@ g_log_default_handler (const gchar *log_domain,
gchar level_prefix[STRING_BUFFER_SIZE], *string;
GString *gstring;
int fd;
const gchar *domains;
if ((log_level & DEFAULT_LEVELS) || (log_level >> G_LOG_LEVEL_USER_SHIFT))
goto emit;
domains = g_getenv ("G_MESSAGES_DEBUG");
if (((log_level & INFO_LEVELS) == 0) ||
domains == NULL ||
(strcmp (domains, "all") != 0 && !strstr (domains, log_domain)))
return;
emit:
/* we can be called externally with recursion for whatever reason */
if (log_level & G_LOG_FLAG_RECURSION)
{

View File

@ -100,16 +100,37 @@ test_default_handler (void)
exit (0);
}
g_test_trap_assert_passed ();
g_test_trap_assert_stdout_unmatched ("*INFO*message5*");
g_setenv ("G_MESSAGES_DEBUG", "foo bar baz", TRUE);
if (g_test_trap_fork (0, G_TEST_TRAP_SILENCE_STDOUT))
{
g_log ("bar", G_LOG_LEVEL_INFO, "message5");
exit (0);
}
g_test_trap_assert_passed ();
g_test_trap_assert_stdout ("*INFO*message5*");
if (g_test_trap_fork (0, G_TEST_TRAP_SILENCE_STDOUT))
{
g_debug ("message6");
g_log ("baz", G_LOG_LEVEL_DEBUG, "message6");
exit (0);
}
g_test_trap_assert_passed ();
g_test_trap_assert_stdout ("*DEBUG*message6*");
g_setenv ("G_MESSAGES_DEBUG", "all", TRUE);
if (g_test_trap_fork (0, G_TEST_TRAP_SILENCE_STDOUT))
{
g_log ("foo", G_LOG_LEVEL_DEBUG, "6");
g_log ("bar", G_LOG_LEVEL_DEBUG, "6");
g_log ("baz", G_LOG_LEVEL_DEBUG, "6");
exit (0);
}
g_test_trap_assert_passed ();
g_test_trap_assert_stdout ("*DEBUG*6*6*6*");
g_unsetenv ("G_MESSAGES_DEBUG");
if (g_test_trap_fork (0, G_TEST_TRAP_SILENCE_STDOUT))
{
g_log (G_LOG_DOMAIN, 1<<10, "message7");