[alsa-devel] [PATCH 07/35] axfer: add support for a container of raw data
Takashi Sakamoto
o-takashi at sakamocchi.jp
Tue Nov 13 07:41:19 CET 2018
This commit adds support for raw data without any headers/chunks/blocks.
A parser of container cannot recognize format of sample without
supplemental information.
Additionally, it includes no magic bytes. A parser of container should
process first several bytes as a part of PCM frames, instead of magic
bytes.
Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
axfer/Makefile.am | 3 +-
axfer/container-raw.c | 66 +++++++++++++++++++++++++++++++++++++++++++
axfer/container.c | 37 ++++++++++++++++++++----
axfer/container.h | 4 +++
4 files changed, 103 insertions(+), 7 deletions(-)
create mode 100644 axfer/container-raw.c
diff --git a/axfer/Makefile.am b/axfer/Makefile.am
index 48d046e..f1ec1d1 100644
--- a/axfer/Makefile.am
+++ b/axfer/Makefile.am
@@ -27,4 +27,5 @@ axfer_SOURCES = \
container.c \
container-riff-wave.c \
container-au.c \
- container-voc.c
+ container-voc.c \
+ container-raw.c
diff --git a/axfer/container-raw.c b/axfer/container-raw.c
new file mode 100644
index 00000000..9b0022e
--- /dev/null
+++ b/axfer/container-raw.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// container-raw.c - a parser/builder for a container with raw data frame.
+//
+// Copyright (c) 2018 Takashi Sakamoto <o-takashi at sakamocchi.jp>
+//
+// Licensed under the terms of the GNU General Public License, version 2.
+
+#include "container.h"
+#include "misc.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+static int raw_builder_pre_process(struct container_context *cntr,
+ snd_pcm_format_t *sample_format,
+ unsigned int *samples_per_frame,
+ unsigned int *frames_per_second,
+ uint64_t *byte_count)
+{
+ *byte_count = UINT64_MAX;
+
+ return 0;
+}
+
+static int raw_parser_pre_process(struct container_context *cntr,
+ snd_pcm_format_t *sample_format,
+ unsigned int *samples_per_frame,
+ unsigned int *frames_per_second,
+ uint64_t *byte_count)
+{
+ struct stat buf = {0};
+ int err;
+
+ if (cntr->stdio) {
+ *byte_count = UINT64_MAX;
+ return 0;
+ }
+
+ err = fstat(cntr->fd, &buf);
+ if (err < 0)
+ return err;
+
+ *byte_count = buf.st_size;
+ if (*byte_count == 0)
+ *byte_count = UINT64_MAX;
+
+ return 0;
+}
+
+const struct container_parser container_parser_raw = {
+ .format = CONTAINER_FORMAT_RAW,
+ .max_size = UINT64_MAX,
+ .ops = {
+ .pre_process = raw_parser_pre_process,
+ },
+};
+
+const struct container_builder container_builder_raw = {
+ .format = CONTAINER_FORMAT_RAW,
+ .max_size = UINT64_MAX,
+ .ops = {
+ .pre_process = raw_builder_pre_process,
+ },
+};
diff --git a/axfer/container.c b/axfer/container.c
index 94afb2b..690fe5b 100644
--- a/axfer/container.c
+++ b/axfer/container.c
@@ -23,15 +23,16 @@ static const char *const cntr_format_labels[] = {
[CONTAINER_FORMAT_RIFF_WAVE] = "riff/wave",
[CONTAINER_FORMAT_AU] = "au",
[CONTAINER_FORMAT_VOC] = "voc",
+ [CONTAINER_FORMAT_RAW] = "raw",
};
static const char *const suffixes[] = {
[CONTAINER_FORMAT_RIFF_WAVE] = ".wav",
[CONTAINER_FORMAT_AU] = ".au",
[CONTAINER_FORMAT_VOC] = ".voc",
+ [CONTAINER_FORMAT_RAW] = "",
};
-
const char *const container_suffix_from_format(enum container_format format)
{
return suffixes[format];
@@ -108,7 +109,7 @@ enum container_format container_format_from_path(const char *path)
}
// Unsupported.
- return CONTAINER_FORMAT_COUNT;
+ return CONTAINER_FORMAT_RAW;
}
int container_seek_offset(struct container_context *cntr, off64_t offset)
@@ -196,7 +197,7 @@ int container_parser_init(struct container_context *cntr,
// Unless detected, use raw container.
if (i == ARRAY_SIZE(parsers))
- return -EINVAL;
+ parser = &container_parser_raw;
// Allocate private data for the parser.
if (parser->private_size > 0) {
@@ -224,6 +225,7 @@ int container_builder_init(struct container_context *cntr,
[CONTAINER_FORMAT_RIFF_WAVE] = &container_builder_riff_wave,
[CONTAINER_FORMAT_AU] = &container_builder_au,
[CONTAINER_FORMAT_VOC] = &container_builder_voc,
+ [CONTAINER_FORMAT_RAW] = &container_builder_raw,
};
const struct container_builder *builder;
int err;
@@ -302,6 +304,16 @@ int container_context_pre_process(struct container_context *cntr,
return 0;
}
+ if (cntr->format == CONTAINER_FORMAT_RAW) {
+ if (*format == SND_PCM_FORMAT_UNKNOWN ||
+ *samples_per_frame == 0 || *frames_per_second == 0) {
+ fprintf(stderr,
+ "Any file format is not detected. Need to "
+ "indicate all of sample format, channels and "
+ "rate explicitly.\n");
+ return -EINVAL;
+ }
+ }
assert(*format >= SND_PCM_FORMAT_S8);
assert(*format <= SND_PCM_FORMAT_LAST);
assert(*samples_per_frame > 0);
@@ -348,6 +360,7 @@ int container_context_process_frames(struct container_context *cntr,
char *buf = frame_buffer;
unsigned int bytes_per_frame;
unsigned int byte_count;
+ unsigned int target_byte_count;
int err;
assert(cntr);
@@ -356,7 +369,19 @@ int container_context_process_frames(struct container_context *cntr,
assert(frame_count);
bytes_per_frame = cntr->bytes_per_sample * cntr->samples_per_frame;
- byte_count = *frame_count * bytes_per_frame;
+ target_byte_count = *frame_count * bytes_per_frame;
+
+ // A parser of cotainers already read first 4 bytes to detect format
+ // of container, however they includes PCM frames when any format was
+ // undetected. Surely to write out them.
+ byte_count = target_byte_count;
+ if (cntr->format == CONTAINER_FORMAT_RAW &&
+ cntr->type == CONTAINER_TYPE_PARSER && !cntr->magic_handled) {
+ memcpy(buf, cntr->magic, sizeof(cntr->magic));
+ buf += sizeof(cntr->magic);
+ byte_count -= sizeof(cntr->magic);
+ cntr->magic_handled = true;
+ }
// Each container has limitation for its volume for sample data.
if (cntr->handled_byte_count > cntr->max_size - byte_count)
@@ -370,11 +395,11 @@ int container_context_process_frames(struct container_context *cntr,
return err;
}
- cntr->handled_byte_count += byte_count;
+ cntr->handled_byte_count += target_byte_count;
if (cntr->handled_byte_count == cntr->max_size)
cntr->eof = true;
- *frame_count = byte_count / bytes_per_frame;
+ *frame_count = target_byte_count / bytes_per_frame;
return 0;
}
diff --git a/axfer/container.h b/axfer/container.h
index 71e188c..2c0c4cf 100644
--- a/axfer/container.h
+++ b/axfer/container.h
@@ -28,6 +28,7 @@ enum container_format {
CONTAINER_FORMAT_RIFF_WAVE = 0,
CONTAINER_FORMAT_AU,
CONTAINER_FORMAT_VOC,
+ CONTAINER_FORMAT_RAW,
CONTAINER_FORMAT_COUNT,
};
@@ -119,4 +120,7 @@ extern const struct container_builder container_builder_au;
extern const struct container_parser container_parser_voc;
extern const struct container_builder container_builder_voc;
+const struct container_parser container_parser_raw;
+const struct container_builder container_builder_raw;
+
#endif
--
2.19.1
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