Mercurial > sdl-ios-xcode
view test/acinclude.m4 @ 4216:5b99971a27b4 SDL-1.2
Fixed bug #698
Hans de Goede 2009-02-13 01:10:52 PST
Since the new "glitch free" version of pulseaudio (used in Fedora 10 amongst
others), the sound of SDL using apps (like a simple playmus call) has been
crackling.
While looking in to fixing this I noticed that the current pulseaudio code in
SDL uses pa_simple. However pa_simple uses a thread to pump pulseaudio events
and ipc, given that SDL already has its own thread for audio handling this is
clearly suboptimal, leading to unnecessary context switching IPC, etc. Also
pa_simple does not allow one to implement the WaitAudio() callback for SDL
audiodrivers properly.
Given that my work is mostly a rewrite (although some original pieces remain)
I'm attaching the new .c and .h file, as that is easier to review then the huge
diff.
Let me know if you also want the diff.
This new version has the following features:
-no longer use an additional thread next to the SDL sound thread
-do not crackle with glitch free audio
-when used with a newer pulse, which does glitch free audio, the total latency
is
the same as with the alsa driver
-proper WaitAudio() implementation, saving another mixlen worth of latency
-adds a WaitDone() implementation
This patch has been written in consultancy with Lennart Poetering (the
pulseaudio author) and has been reviewed by him for correct use of the pa API.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 21 Sep 2009 09:27:08 +0000 |
parents | 91063c450171 |
children |
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# Configure paths for SDL # Sam Lantinga 9/21/99 # stolen from Manish Singh # stolen back from Frank Belew # stolen from Manish Singh # Shamelessly stolen from Owen Taylor dnl AM_PATH_SDL([MINIMUM-VERSION, [ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]]]) dnl Test for SDL, and define SDL_CFLAGS and SDL_LIBS dnl AC_DEFUN([AM_PATH_SDL], [dnl dnl Get the cflags and libraries from the sdl-config script dnl AC_ARG_WITH(sdl-prefix,[ --with-sdl-prefix=PFX Prefix where SDL is installed (optional)], sdl_prefix="$withval", sdl_prefix="") AC_ARG_WITH(sdl-exec-prefix,[ --with-sdl-exec-prefix=PFX Exec prefix where SDL is installed (optional)], sdl_exec_prefix="$withval", sdl_exec_prefix="") AC_ARG_ENABLE(sdltest, [ --disable-sdltest Do not try to compile and run a test SDL program], , enable_sdltest=yes) if test x$sdl_exec_prefix != x ; then sdl_args="$sdl_args --exec-prefix=$sdl_exec_prefix" if test x${SDL_CONFIG+set} != xset ; then SDL_CONFIG=$sdl_exec_prefix/bin/sdl-config fi fi if test x$sdl_prefix != x ; then sdl_args="$sdl_args --prefix=$sdl_prefix" if test x${SDL_CONFIG+set} != xset ; then SDL_CONFIG=$sdl_prefix/bin/sdl-config fi fi if test "x$prefix" != xNONE; then PATH="$prefix/bin:$prefix/usr/bin:$PATH" fi AC_PATH_PROG(SDL_CONFIG, sdl-config, no, [$PATH]) min_sdl_version=ifelse([$1], ,0.11.0,$1) AC_MSG_CHECKING(for SDL - version >= $min_sdl_version) no_sdl="" if test "$SDL_CONFIG" = "no" ; then no_sdl=yes else SDL_CFLAGS=`$SDL_CONFIG $sdlconf_args --cflags` SDL_LIBS=`$SDL_CONFIG $sdlconf_args --libs` sdl_major_version=`$SDL_CONFIG $sdl_args --version | \ sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\1/'` sdl_minor_version=`$SDL_CONFIG $sdl_args --version | \ sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\2/'` sdl_micro_version=`$SDL_CONFIG $sdl_config_args --version | \ sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\3/'` if test "x$enable_sdltest" = "xyes" ; then ac_save_CFLAGS="$CFLAGS" ac_save_CXXFLAGS="$CXXFLAGS" ac_save_LIBS="$LIBS" CFLAGS="$CFLAGS $SDL_CFLAGS" CXXFLAGS="$CXXFLAGS $SDL_CFLAGS" LIBS="$LIBS $SDL_LIBS" dnl dnl Now check if the installed SDL is sufficiently new. (Also sanity dnl checks the results of sdl-config to some extent dnl rm -f conf.sdltest AC_TRY_RUN([ #include <stdio.h> #include <stdlib.h> #include <string.h> #include "SDL.h" char* my_strdup (char *str) { char *new_str; if (str) { new_str = (char *)malloc ((strlen (str) + 1) * sizeof(char)); strcpy (new_str, str); } else new_str = NULL; return new_str; } int main (int argc, char *argv[]) { int major, minor, micro; char *tmp_version; /* This hangs on some systems (?) system ("touch conf.sdltest"); */ { FILE *fp = fopen("conf.sdltest", "a"); if ( fp ) fclose(fp); } /* HP/UX 9 (%@#!) writes to sscanf strings */ tmp_version = my_strdup("$min_sdl_version"); if (sscanf(tmp_version, "%d.%d.%d", &major, &minor, µ) != 3) { printf("%s, bad version string\n", "$min_sdl_version"); exit(1); } if (($sdl_major_version > major) || (($sdl_major_version == major) && ($sdl_minor_version > minor)) || (($sdl_major_version == major) && ($sdl_minor_version == minor) && ($sdl_micro_version >= micro))) { return 0; } else { printf("\n*** 'sdl-config --version' returned %d.%d.%d, but the minimum version\n", $sdl_major_version, $sdl_minor_version, $sdl_micro_version); printf("*** of SDL required is %d.%d.%d. If sdl-config is correct, then it is\n", major, minor, micro); printf("*** best to upgrade to the required version.\n"); printf("*** If sdl-config was wrong, set the environment variable SDL_CONFIG\n"); printf("*** to point to the correct copy of sdl-config, and remove the file\n"); printf("*** config.cache before re-running configure\n"); return 1; } } ],, no_sdl=yes,[echo $ac_n "cross compiling; assumed OK... $ac_c"]) CFLAGS="$ac_save_CFLAGS" CXXFLAGS="$ac_save_CXXFLAGS" LIBS="$ac_save_LIBS" fi fi if test "x$no_sdl" = x ; then AC_MSG_RESULT(yes) ifelse([$2], , :, [$2]) else AC_MSG_RESULT(no) if test "$SDL_CONFIG" = "no" ; then echo "*** The sdl-config script installed by SDL could not be found" echo "*** If SDL was installed in PREFIX, make sure PREFIX/bin is in" echo "*** your path, or set the SDL_CONFIG environment variable to the" echo "*** full path to sdl-config." else if test -f conf.sdltest ; then : else echo "*** Could not run SDL test program, checking why..." CFLAGS="$CFLAGS $SDL_CFLAGS" CXXFLAGS="$CXXFLAGS $SDL_CFLAGS" LIBS="$LIBS $SDL_LIBS" AC_TRY_LINK([ #include <stdio.h> #include "SDL.h" int main(int argc, char *argv[]) { return 0; } #undef main #define main K_and_R_C_main ], [ return 0; ], [ echo "*** The test program compiled, but did not run. This usually means" echo "*** that the run-time linker is not finding SDL or finding the wrong" echo "*** version of SDL. If it is not finding SDL, you'll need to set your" echo "*** LD_LIBRARY_PATH environment variable, or edit /etc/ld.so.conf to point" echo "*** to the installed location Also, make sure you have run ldconfig if that" echo "*** is required on your system" echo "***" echo "*** If you have an old version installed, it is best to remove it, although" echo "*** you may also be able to get things to work by modifying LD_LIBRARY_PATH"], [ echo "*** The test program failed to compile or link. See the file config.log for the" echo "*** exact error that occured. This usually means SDL was incorrectly installed" echo "*** or that you have moved SDL since it was installed. In the latter case, you" echo "*** may want to edit the sdl-config script: $SDL_CONFIG" ]) CFLAGS="$ac_save_CFLAGS" CXXFLAGS="$ac_save_CXXFLAGS" LIBS="$ac_save_LIBS" fi fi SDL_CFLAGS="" SDL_LIBS="" ifelse([$3], , :, [$3]) fi AC_SUBST(SDL_CFLAGS) AC_SUBST(SDL_LIBS) rm -f conf.sdltest ])