use alsa m4 stuff to generate configure

git-svn-id: https://svn.musicpd.org/mpd/trunk@2916 09075e82-0dd4-0310-85a5-a0d7c8717e4f

TODO

@@ -40,13 +40,16 @@
 *) Handle mp1 and mp2 files (including mp2's that are disguised as mp3's with 
 	a mp3 suffix)
 
-*) use alsa aclocal/m4 stuff
-
 *) choose id3v2 over id3v1 tags when both are present
 
 *) add error codes for status->error
 
-*) add support fore mousepack/mpc files
+*) add support for mousepack/mpc files
+
+*) add alsa audioOutput plugin
+
+*) add a method for closing the audio device immediatly w/o waiting for an
+   empty audio device buffer.  This isn't possible via libao api.
 
 0.13
 ----

configure.ac

@@ -117,25 +117,7 @@ fi
 AC_CHECK_HEADER(sys/soundcard.h,[enable_oss=yes;AC_DEFINE(HAVE_OSS,1,[Define to enable OSS])],[AC_MSG_WARN(Soundcard headers not found -- disabling OSS support);enable_oss=no])
 
 if test x$enable_alsa = xyes; then
-	AC_MSG_CHECKING(for alsa)
+	AM_PATH_ALSA(0.9.0, , enable_alsa=no)
-	AC_EGREP_CPP([AP_maGiC_VALUE],
-	[
-#include <alsa/asoundlib.h>
-#if defined(SND_LIB_MAJOR) && defined(SND_LIB_MINOR)
-#if SND_LIB_MAJOR>0 || (SND_LIB_MAJOR==0 && SND_LIB_MINOR>=6)
-AP_maGiC_VALUE
-#endif
-#endif
-	],
-	enable_alsa=yes
-	AC_MSG_RESULT([yes]),
-	enable_alsa=no
-	AC_MSG_RESULT([no])
-	)
-fi
-
-if test x$enable_alsa = xyes; then
-	AC_CHECK_LIB(asound,main,[MPD_LIBS="$MPD_LIBS -lasound";AC_DEFINE(HAVE_ALSA,1,[Define if alsa support is present])],enable_alsa=no)
 fi
 
 if test x$enable_iconv = xyes; then

m4/alsa.m4

@@ -0,0 +1,142 @@
+dnl Configure Paths for Alsa
+dnl Some modifications by Richard Boulton <richard-alsa@tartarus.org>
+dnl Christopher Lansdown <lansdoct@cs.alfred.edu>
+dnl Jaroslav Kysela <perex@suse.cz>
+dnl Last modification: alsa.m4,v 1.23 2004/01/16 18:14:22 tiwai Exp
+dnl AM_PATH_ALSA([MINIMUM-VERSION [, ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]]])
+dnl Test for libasound, and define ALSA_CFLAGS and ALSA_LIBS as appropriate.
+dnl enables arguments --with-alsa-prefix=
+dnl                   --with-alsa-enc-prefix=
+dnl                   --disable-alsatest
+dnl
+dnl For backwards compatibility, if ACTION_IF_NOT_FOUND is not specified,
+dnl and the alsa libraries are not found, a fatal AC_MSG_ERROR() will result.
+dnl
+AC_DEFUN([AM_PATH_ALSA],
+[dnl Save the original CFLAGS, LDFLAGS, and LIBS
+alsa_save_CFLAGS="$CFLAGS"
+alsa_save_LDFLAGS="$LDFLAGS"
+alsa_save_LIBS="$LIBS"
+alsa_found=yes
+
+dnl
+dnl Get the cflags and libraries for alsa
+dnl
+AC_ARG_WITH(alsa-prefix,
+[  --with-alsa-prefix=PFX  Prefix where Alsa library is installed(optional)],
+[alsa_prefix="$withval"], [alsa_prefix=""])
+
+AC_ARG_WITH(alsa-inc-prefix,
+[  --with-alsa-inc-prefix=PFX  Prefix where include libraries are (optional)],
+[alsa_inc_prefix="$withval"], [alsa_inc_prefix=""])
+
+dnl FIXME: this is not yet implemented
+AC_ARG_ENABLE(alsatest,
+[  --disable-alsatest      Do not try to compile and run a test Alsa program],
+[enable_alsatest="$enableval"],
+[enable_alsatest=yes])
+
+dnl Add any special include directories
+AC_MSG_CHECKING(for ALSA CFLAGS)
+if test "$alsa_inc_prefix" != "" ; then
+	ALSA_CFLAGS="$ALSA_CFLAGS -I$alsa_inc_prefix"
+	CFLAGS="$CFLAGS -I$alsa_inc_prefix"
+fi
+AC_MSG_RESULT($ALSA_CFLAGS)
+CFLAGS="$alsa_save_CFLAGS"
+
+dnl add any special lib dirs
+AC_MSG_CHECKING(for ALSA LDFLAGS)
+if test "$alsa_prefix" != "" ; then
+	ALSA_LIBS="$ALSA_LIBS -L$alsa_prefix"
+	LDFLAGS="$LDFLAGS $ALSA_LIBS"
+fi
+
+dnl add the alsa library
+ALSA_LIBS="$ALSA_LIBS -lasound -lm -ldl -lpthread"
+LIBS=`echo $LIBS | sed 's/-lm//'`
+LIBS=`echo $LIBS | sed 's/-ldl//'`
+LIBS=`echo $LIBS | sed 's/-lpthread//'`
+LIBS=`echo $LIBS | sed 's/  //'`
+LIBS="$ALSA_LIBS $LIBS"
+AC_MSG_RESULT($ALSA_LIBS)
+
+dnl Check for a working version of libasound that is of the right version.
+min_alsa_version=ifelse([$1], ,0.1.1,$1)
+AC_MSG_CHECKING(for libasound headers version >= $min_alsa_version)
+no_alsa=""
+    alsa_min_major_version=`echo $min_alsa_version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\1/'`
+    alsa_min_minor_version=`echo $min_alsa_version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\2/'`
+    alsa_min_micro_version=`echo $min_alsa_version | \
+           sed 's/\([[0-9]]*\).\([[0-9]]*\).\([[0-9]]*\)/\3/'`
+
+AC_LANG_SAVE
+AC_LANG_C
+AC_TRY_COMPILE([
+#include <alsa/asoundlib.h>
+], [
+/* ensure backward compatibility */
+#if !defined(SND_LIB_MAJOR) && defined(SOUNDLIB_VERSION_MAJOR)
+#define SND_LIB_MAJOR SOUNDLIB_VERSION_MAJOR
+#endif
+#if !defined(SND_LIB_MINOR) && defined(SOUNDLIB_VERSION_MINOR)
+#define SND_LIB_MINOR SOUNDLIB_VERSION_MINOR
+#endif
+#if !defined(SND_LIB_SUBMINOR) && defined(SOUNDLIB_VERSION_SUBMINOR)
+#define SND_LIB_SUBMINOR SOUNDLIB_VERSION_SUBMINOR
+#endif
+
+#  if(SND_LIB_MAJOR > $alsa_min_major_version)
+  exit(0);
+#  else
+#    if(SND_LIB_MAJOR < $alsa_min_major_version)
+#       error not present
+#    endif
+
+#   if(SND_LIB_MINOR > $alsa_min_minor_version)
+  exit(0);
+#   else
+#     if(SND_LIB_MINOR < $alsa_min_minor_version)
+#          error not present
+#      endif
+
+#      if(SND_LIB_SUBMINOR < $alsa_min_micro_version)
+#        error not present
+#      endif
+#    endif
+#  endif
+exit(0);
+],
+  [AC_MSG_RESULT(found.)],
+  [AC_MSG_RESULT(not present.)
+   ifelse([$3], , [AC_MSG_ERROR(Sufficiently new version of libasound not found.)])
+   alsa_found=no]
+)
+AC_LANG_RESTORE
+
+dnl Now that we know that we have the right version, let's see if we have the library and not just the headers.
+if test "x$enable_alsatest" = "xyes"; then
+AC_CHECK_LIB([asound], [snd_ctl_open],,
+	[ifelse([$3], , [AC_MSG_ERROR(No linkable libasound was found.)])
+	 alsa_found=no]
+)
+fi
+
+LDFLAGS="$alsa_save_LDFLAGS"
+LIBS="$alsa_save_LIBS"
+
+if test "x$alsa_found" = "xyes" ; then
+   ifelse([$2], , :, [$2])
+else
+   ALSA_CFLAGS=""
+   ALSA_LIBS=""
+   ifelse([$3], , :, [$3])
+fi
+
+dnl That should be it.  Now just export out symbols:
+AC_SUBST(ALSA_CFLAGS)
+AC_SUBST(ALSA_LIBS)
+])
+