Configure dynamically generates SDL_config.h

I'm still wrestling with autoheader, but this should work for now...
Fixed lots of build problems with C library support disabled

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%401345

src/audio/SDL_audio.c

@@ -306,18 +306,20 @@ int SDL_AudioInit(const char *driver_name)
 		 */
 		for ( i=0; bootstrap[i]; ++i ) {
 			if ( SDL_strcmp(bootstrap[i]->name, "esd") == 0 ) {
+#ifdef HAVE_PUTENV
 				const char *esd_no_spawn;
 
 				/* Don't start ESD if it's not running */
-				esd_no_spawn = SDL_getenv("ESD_NO_SPAWN");
+				esd_no_spawn = getenv("ESD_NO_SPAWN");
 				if ( esd_no_spawn == NULL ) {
 					putenv("ESD_NO_SPAWN=1");
 				}
+#endif
 				if ( bootstrap[i]->available() ) {
 					audio = bootstrap[i]->create(0);
 					break;
 				}
-#ifdef linux	/* No unsetenv() on most platforms */
+#ifdef HAVE_UNSETENV
 				if ( esd_no_spawn == NULL ) {
 					unsetenv("ESD_NO_SPAWN");
 				}

src/audio/amigaos/SDL_ahiaudio.c

@@ -22,6 +22,8 @@
 
 /* Allow access to a raw mixing buffer (for AmigaOS) */
 
+#include "SDL_stdlib.h"
+#include "SDL_string.h"
 #include "SDL_endian.h"
 #include "SDL_audio.h"
 #include "SDL_audiomem.h"

src/audio/disk/SDL_diskaudio.c

@@ -26,6 +26,7 @@
 /* Output raw audio data to a file. */
 
 #include <stdio.h>
+#include <string.h>	/* For strerror() */
 #include <errno.h>
 #include <unistd.h>
 #include <sys/stat.h>
@@ -130,7 +131,7 @@ static SDL_AudioDevice *DISKAUD_CreateDevice(int devindex)
 	SDL_memset(this->hidden, 0, (sizeof *this->hidden));
 
     envr = SDL_getenv(DISKENVR_WRITEDELAY);
-    this->hidden->write_delay = (envr) ? atoi(envr) : DISKDEFAULT_WRITEDELAY;
+    this->hidden->write_delay = (envr) ? SDL_atoi(envr) : DISKDEFAULT_WRITEDELAY;
 
 	/* Set the function pointers */
 	this->OpenAudio = DISKAUD_OpenAudio;

src/audio/dma/SDL_dmaaudio.c

@@ -23,6 +23,7 @@
 /* Allow access to a raw mixing buffer */
 
 #include <stdio.h>
+#include <string.h>	/* For strerror() */
 #include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>

src/audio/dsp/SDL_dspaudio.c

@@ -25,7 +25,8 @@
 
 /* Allow access to a raw mixing buffer */
 
-#include <stdio.h>	/* For perror() ... should we really do this? */
+#include <stdio.h>	/* For perror() */
+#include <string.h>	/* For strerror() */
 #include <errno.h>
 #include <unistd.h>
 #include <fcntl.h>

src/audio/mme/SDL_mmeaudio.h

@@ -24,6 +24,8 @@
 
 #include <mme_api.h>
 
+#include "SDL_stdlib.h"
+#include "SDL_string.h"
 #include "SDL_audio.h"
 #include "SDL_mutex.h"
 #include "SDL_timer.h"