Add a project setting to enable stdout flushing in release builds

This can be used in server builds for journalctl compatibility.

(cherry picked from commit 341b9cf15a)
This commit is contained in:
Hugo Locurcio 2020-12-15 14:40:09 +01:00 committed by Rémi Verschelde
parent 2753cc5264
commit f5f04a10f5
No known key found for this signature in database
GPG key ID: C3336907360768E1
3 changed files with 24 additions and 9 deletions

View file

@ -33,6 +33,7 @@
#include "core/os/dir_access.h"
#include "core/os/os.h"
#include "core/print_string.h"
#include "core/project_settings.h"
// va_copy was defined in the C99, but not in C++ standards before C++11.
// When you compile C++ without --std=c++<XX> option, compilers still define
@ -204,15 +205,14 @@ void RotatedFileLogger::logv(const char *p_format, va_list p_list, bool p_err) {
}
va_end(list_copy);
file->store_buffer((uint8_t *)buf, len);
if (len >= static_buf_size) {
Memory::free_static(buf);
}
#ifdef DEBUG_ENABLED
const bool need_flush = true;
#else
bool need_flush = p_err;
#endif
if (need_flush) {
if (p_err || GLOBAL_GET("application/run/flush_stdout_on_print")) {
// Don't always flush when printing stdout to avoid performance
// issues when `print()` is spammed in release builds.
file->flush();
}
}
@ -231,9 +231,11 @@ void StdLogger::logv(const char *p_format, va_list p_list, bool p_err) {
vfprintf(stderr, p_format, p_list);
} else {
vprintf(p_format, p_list);
#ifdef DEBUG_ENABLED
fflush(stdout);
#endif
if (GLOBAL_GET("application/run/flush_stdout_on_print")) {
// Don't always flush when printing stdout to avoid performance
// issues when `print()` is spammed in release builds.
fflush(stdout);
}
}
}

View file

@ -248,6 +248,14 @@
<member name="application/run/disable_stdout" type="bool" setter="" getter="" default="false">
If [code]true[/code], disables printing to standard output in an exported build.
</member>
<member name="application/run/flush_stdout_on_print" type="bool" setter="" getter="" default="false">
If [code]true[/code], flushes the standard output stream every time a line is printed. This affects both terminal logging and file logging.
When running a project, this setting must be enabled if you want logs to be collected by service managers such as systemd/journalctl. This setting is disabled by default on release builds, since flushing on every printed line will negatively affect performance if lots of lines are printed in a rapid succession. Also, if this setting is enabled, logged files will still be written successfully if the application crashes or is otherwise killed by the user (without being closed "normally").
[b]Note:[/b] Regardless of this setting, the standard error stream ([code]stderr[/code]) is always flushed when a line is printed to it.
</member>
<member name="application/run/flush_stdout_on_print.debug" type="bool" setter="" getter="" default="true">
Debug build override for [member application/run/flush_stdout_on_print], as performance is less important during debugging.
</member>
<member name="application/run/frame_delay_msec" type="int" setter="" getter="" default="0">
Forces a delay between frames in the main loop (in milliseconds). This may be useful if you plan to disable vertical synchronization.
</member>

View file

@ -971,6 +971,11 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
}
#endif
// Only flush stdout in debug builds by default, as spamming `print()` will
// decrease performance if this is enabled.
GLOBAL_DEF("application/run/flush_stdout_on_print", false);
GLOBAL_DEF("application/run/flush_stdout_on_print.debug", true);
GLOBAL_DEF("logging/file_logging/enable_file_logging", false);
// Only file logging by default on desktop platforms as logs can't be
// accessed easily on mobile/Web platforms (if at all).