Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 191 insertions, 0 deletions

diff --git a/audio/wavcapture.c b/audio/wavcapture.c
new file mode 100644
index 000000000..c60286e16
--- /dev/null
+++ b/audio/wavcapture.c
@@ -0,0 +1,191 @@
+#include "qemu/osdep.h"
+#include "qemu/qemu-print.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "audio.h"
+
+typedef struct {
+    FILE *f;
+    int bytes;
+    char *path;
+    int freq;
+    int bits;
+    int nchannels;
+    CaptureVoiceOut *cap;
+} WAVState;
+
+/* VICE code: Store number as little endian. */
+static void le_store (uint8_t *buf, uint32_t val, int len)
+{
+    int i;
+    for (i = 0; i < len; i++) {
+        buf[i] = (uint8_t) (val & 0xff);
+        val >>= 8;
+    }
+}
+
+static void wav_notify (void *opaque, audcnotification_e cmd)
+{
+    (void) opaque;
+    (void) cmd;
+}
+
+static void wav_destroy (void *opaque)
+{
+    WAVState *wav = opaque;
+    uint8_t rlen[4];
+    uint8_t dlen[4];
+    uint32_t datalen = wav->bytes;
+    uint32_t rifflen = datalen + 36;
+
+    if (wav->f) {
+        le_store (rlen, rifflen, 4);
+        le_store (dlen, datalen, 4);
+
+        if (fseek (wav->f, 4, SEEK_SET)) {
+            error_report("wav_destroy: rlen fseek failed: %s",
+                         strerror(errno));
+            goto doclose;
+        }
+        if (fwrite (rlen, 4, 1, wav->f) != 1) {
+            error_report("wav_destroy: rlen fwrite failed: %s",
+                         strerror(errno));
+            goto doclose;
+        }
+        if (fseek (wav->f, 32, SEEK_CUR)) {
+            error_report("wav_destroy: dlen fseek failed: %s",
+                         strerror(errno));
+            goto doclose;
+        }
+        if (fwrite (dlen, 1, 4, wav->f) != 4) {
+            error_report("wav_destroy: dlen fwrite failed: %s",
+                         strerror(errno));
+            goto doclose;
+        }
+    doclose:
+        if (fclose (wav->f)) {
+            error_report("wav_destroy: fclose failed: %s", strerror(errno));
+        }
+    }
+
+    g_free (wav->path);
+}
+
+static void wav_capture(void *opaque, const void *buf, int size)
+{
+    WAVState *wav = opaque;
+
+    if (fwrite (buf, size, 1, wav->f) != 1) {
+        error_report("wav_capture: fwrite error: %s", strerror(errno));
+    }
+    wav->bytes += size;
+}
+
+static void wav_capture_destroy (void *opaque)
+{
+    WAVState *wav = opaque;
+
+    AUD_del_capture (wav->cap, wav);
+    g_free (wav);
+}
+
+static void wav_capture_info (void *opaque)
+{
+    WAVState *wav = opaque;
+    char *path = wav->path;
+
+    qemu_printf("Capturing audio(%d,%d,%d) to %s: %d bytes\n",
+                wav->freq, wav->bits, wav->nchannels,
+                path ? path : "<not available>", wav->bytes);
+}
+
+static struct capture_ops wav_capture_ops = {
+    .destroy = wav_capture_destroy,
+    .info = wav_capture_info
+};
+
+int wav_start_capture(AudioState *state, CaptureState *s, const char *path,
+                      int freq, int bits, int nchannels)
+{
+    WAVState *wav;
+    uint8_t hdr[] = {
+        0x52, 0x49, 0x46, 0x46, 0x00, 0x00, 0x00, 0x00, 0x57, 0x41, 0x56,
+        0x45, 0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00,
+        0x02, 0x00, 0x44, 0xac, 0x00, 0x00, 0x10, 0xb1, 0x02, 0x00, 0x04,
+        0x00, 0x10, 0x00, 0x64, 0x61, 0x74, 0x61, 0x00, 0x00, 0x00, 0x00
+    };
+    struct audsettings as;
+    struct audio_capture_ops ops;
+    int stereo, bits16, shift;
+    CaptureVoiceOut *cap;
+
+    if (bits != 8 && bits != 16) {
+        error_report("incorrect bit count %d, must be 8 or 16", bits);
+        return -1;
+    }
+
+    if (nchannels != 1 && nchannels != 2) {
+        error_report("incorrect channel count %d, must be 1 or 2",
+                     nchannels);
+        return -1;
+    }
+
+    stereo = nchannels == 2;
+    bits16 = bits == 16;
+
+    as.freq = freq;
+    as.nchannels = 1 << stereo;
+    as.fmt = bits16 ? AUDIO_FORMAT_S16 : AUDIO_FORMAT_U8;
+    as.endianness = 0;
+
+    ops.notify = wav_notify;
+    ops.capture = wav_capture;
+    ops.destroy = wav_destroy;
+
+    wav = g_malloc0 (sizeof (*wav));
+
+    shift = bits16 + stereo;
+    hdr[34] = bits16 ? 0x10 : 0x08;
+
+    le_store (hdr + 22, as.nchannels, 2);
+    le_store (hdr + 24, freq, 4);
+    le_store (hdr + 28, freq << shift, 4);
+    le_store (hdr + 32, 1 << shift, 2);
+
+    wav->f = fopen (path, "wb");
+    if (!wav->f) {
+        error_report("Failed to open wave file `%s': %s",
+                     path, strerror(errno));
+        g_free (wav);
+        return -1;
+    }
+
+    wav->path = g_strdup (path);
+    wav->bits = bits;
+    wav->nchannels = nchannels;
+    wav->freq = freq;
+
+    if (fwrite (hdr, sizeof (hdr), 1, wav->f) != 1) {
+        error_report("Failed to write header: %s", strerror(errno));
+        goto error_free;
+    }
+
+    cap = AUD_add_capture(state, &as, &ops, wav);
+    if (!cap) {
+        error_report("Failed to add audio capture");
+        goto error_free;
+    }
+
+    wav->cap = cap;
+    s->opaque = wav;
+    s->ops = wav_capture_ops;
+    return 0;
+
+error_free:
+    g_free (wav->path);
+    if (fclose (wav->f)) {
+        error_report("Failed to close wave file: %s", strerror(errno));
+    }
+    g_free (wav);
+    return -1;
+}