refactor pcm io routines

[fdkaac.git] / src / pcm_readhelper.c

diff --git a/src/pcm_readhelper.c b/src/pcm_readhelper.c
new file mode 100644 (file)
index 0000000..70b47f5
--- /dev/null
+++ b/src/pcm_readhelper.c
@@ -0,0 +1,154 @@
+/* 
+ * Copyright (C) 2013 nu774
+ * For conditions of distribution and use, see copyright notice in COPYING
+ */
+
+#if HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#if HAVE_STDINT_H
+#  include <stdint.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include "pcm_reader.h"
+#include "m4af_endian.h"
+
+int pcm_read(pcm_io_context_t *io, void *buffer, uint32_t size)
+{
+    int rc;
+    uint32_t count = 0;
+
+    do {
+        rc = io->vtbl->read(io->cookie, buffer, size - count);
+        if (rc > 0)
+            count += rc;
+    } while (rc > 0 && count < size);
+    return count > 0 ? count : rc;
+}
+
+int pcm_skip(pcm_io_context_t *io, int64_t count)
+{
+    char buff[8192];
+    int rc;
+    pcm_io_vtbl_t *vp = io->vtbl;
+
+    if (count == 0 || pcm_seek(io, count, SEEK_CUR) >= 0)
+        return 0;
+    do {
+        if ((rc = vp->read(io->cookie, buff, count > 8192 ? 8192 : count)) > 0)
+            count -= rc;
+    } while (rc > 0 && count > 0);
+
+    return count == 0 ? 0 : -1;
+}
+
+int pcm_read16le(pcm_io_context_t *io, uint16_t *value)
+{
+    if (pcm_read(io, value, 2) == 2) {
+        *value = m4af_ltoh16(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_read16be(pcm_io_context_t *io, uint16_t *value)
+{
+    if (pcm_read(io, value, 2) == 2) {
+        *value = m4af_btoh16(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_read32le(pcm_io_context_t *io, uint32_t *value)
+{
+    if (pcm_read(io, value, 4) == 4) {
+        *value = m4af_ltoh32(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_read32be(pcm_io_context_t *io, uint32_t *value)
+{
+    if (pcm_read(io, value, 4) == 4) {
+        *value = m4af_btoh32(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_read64le(pcm_io_context_t *io, uint64_t *value)
+{
+    if (pcm_read(io, value, 8) == 8) {
+        *value = m4af_ltoh64(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_read64be(pcm_io_context_t *io, uint64_t *value)
+{
+    if (pcm_read(io, value, 8) == 8) {
+        *value = m4af_btoh64(*value);
+        return 0;
+    }
+    return -1;
+}
+
+int pcm_scanl(pcm_io_context_t *io, const char *fmt, ...)
+{
+    int c, count = 0;
+    va_list ap;
+
+    va_start(ap, fmt);
+    while ((c = *fmt++)) {
+        switch (c) {
+        case 'S':
+            TRY_IO(pcm_read16le(io, va_arg(ap, uint16_t*)));
+            ++count;
+            break;
+        case 'L':
+            TRY_IO(pcm_read32le(io, va_arg(ap, uint32_t*)));
+            ++count;
+            break;
+        case 'Q':
+            TRY_IO(pcm_read64le(io, va_arg(ap, uint64_t*)));
+            ++count;
+            break;
+        }
+    }
+FAIL:
+    va_end(ap);
+    return count;
+}
+
+int pcm_scanb(pcm_io_context_t *io, const char *fmt, ...)
+{
+    int c, count = 0;
+    va_list ap;
+
+    va_start(ap, fmt);
+    while ((c = *fmt++)) {
+        switch (c) {
+        case 'S':
+            TRY_IO(pcm_read16be(io, va_arg(ap, uint16_t*)));
+            ++count;
+            break;
+        case 'L':
+            TRY_IO(pcm_read32be(io, va_arg(ap, uint32_t*)));
+            ++count;
+            break;
+        case 'Q':
+            TRY_IO(pcm_read64be(io, va_arg(ap, uint64_t*)));
+            ++count;
+            break;
+        }
+    }
+FAIL:
+    va_end(ap);
+    return count;
+}