*: initial commit of stripped schism stuff

Forking schism tracker's IT playback stuff into a little playback
library for embedding in demos.

1 files changed, 126 insertions, 0 deletions

diff --git a/src/sys/oss/volume-oss.c b/src/sys/oss/volume-oss.c
new file mode 100644
index 0000000..7771307
--- /dev/null
+++ b/src/sys/oss/volume-oss.c
@@ -0,0 +1,126 @@
+/*
+ * Schism Tracker - a cross-platform Impulse Tracker clone
+ * copyright (c) 2003-2005 Storlek <storlek@rigelseven.com>
+ * copyright (c) 2005-2008 Mrs. Brisby <mrs.brisby@nimh.org>
+ * copyright (c) 2009 Storlek & Mrs. Brisby
+ * copyright (c) 2010-2012 Storlek
+ * URL: http://schismtracker.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "headers.h"
+
+#include "util.h"
+#include "log.h"
+
+#ifdef USE_OSS
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/soundcard.h>
+
+#include <errno.h>
+#include <fcntl.h>
+
+/* Hmm. I've found that some systems actually don't support the idea of a
+ * "master" volume, so this became necessary. I suppose PCM is really the
+ * more useful setting to change anyway. */
+#if 0
+# define SCHISM_MIXER_CONTROL SOUND_MIXER_VOLUME
+#else
+# define SCHISM_MIXER_CONTROL SOUND_MIXER_PCM
+#endif
+
+#define VOLUME_MAX 100
+
+/* --------------------------------------------------------------------- */
+
+static const char *device_file = NULL;
+
+/* --------------------------------------------------------------------- */
+
+static int open_mixer_device(void)
+{
+	const char *ptr;
+
+	if (!device_file) {
+		ptr = "/dev/sound/mixer";
+		if (access(ptr, F_OK) < 0) {
+			/* this had better work :) */
+			ptr = "/dev/mixer";
+		}
+		device_file = ptr;
+	}
+
+	return open(device_file, O_RDWR);
+}
+
+/* --------------------------------------------------------------------- */
+
+int oss_volume_get_max(void);
+int oss_volume_get_max(void)
+{
+	return VOLUME_MAX;
+}
+
+void oss_volume_read(int *left, int *right);
+void oss_volume_read(int *left, int *right)
+{
+	int fd;
+	uint8_t volume[4];
+
+	fd = open_mixer_device();
+	if (fd < 0) {
+		log_perror(device_file);
+		*left = *right = 0;
+		return;
+	}
+
+	if (ioctl(fd, MIXER_READ(SCHISM_MIXER_CONTROL), volume) == EOF) {
+		log_perror(device_file);
+		*left = *right = 0;
+	} else {
+		*left = volume[0];
+		*right = volume[1];
+	}
+
+	close(fd);
+}
+
+void oss_volume_write(int left, int right);
+void oss_volume_write(int left, int right)
+{
+	int fd;
+	uint8_t volume[4];
+
+	volume[0] = CLAMP(left, 0, VOLUME_MAX);
+	volume[1] = CLAMP(right, 0, VOLUME_MAX);
+
+	fd = open_mixer_device();
+	if (fd < 0) {
+		log_perror(device_file);
+		return;
+	}
+
+	if (ioctl(fd, MIXER_WRITE(SCHISM_MIXER_CONTROL), volume) == EOF) {
+		log_perror(device_file);
+	}
+
+	close(fd);
+}
+
+#endif