Files
libva-v4l2-request-fourier/src/h265_parser/gst/codecparsers/nalutils.h
T
claude-noether 9f7437e8ee iter2 step2: GLib/GStreamer compat shim, build succeeds
Vendored gsth265parser + nalutils + gstbitreader + gstbytereader (the
Step 1 commit) compile cleanly against libc + libv4l2 only after
adding 1 compat translation unit + 5 stub headers, no edits to the
vendored .c/.h files themselves.

src/h265_parser/gst_compat.{h,c} — new files (MIT, original work):
  - GLib type aliases (gboolean, gchar, gint*, guint*, gsize, gpointer)
  - Memory helpers (g_malloc/g_free as #define free, g_memdup2 inline)
  - Asserts as no-op + parser-return-code-propagation
  - All GST_DEBUG/INFO/WARNING/ERROR/LOG/FIXME as no-ops (the parser
    is heavy on debug logging; we compile it all out)
  - GArray implementation (~100 LOC, just enough for gsth265parser.c's
    24 call sites)
  - GList full struct with .data/.next/.prev so callers compile;
    list-manipulation functions abort() — dead code paths only
  - Byte-order read/write macros (GST_READ_UINT8/16/24/32/64_LE/BE,
    GST_WRITE_UINT8/16/24/32_BE) — aarch64 LE inlines
  - g_once_init_enter/leave as simple gate
  - G_MAXUINT*, G_MAXINT*, G_MINxxx, G_GNUC_* attribute macros, etc.
  - Opaque GstBuffer/GstMemory/GstMapInfo + abort-stub functions for
    the encoder-side SEI-insertion paths the libva backend never invokes
  - gst_util_ceil_log2 real impl (used by slice-header parser; dead
    for our SPS-only call path but cheaper to implement than stub)

src/h265_parser/gst/{gst.h,base/base-prelude.h,base/gstbitwriter.h,
codecparsers/codecparsers-prelude.h,glib-compat-private.h} — 5 new
stub headers (MIT). All include gst_compat.h. gstbitwriter.h adds
abort-stub functions for the bit-writer API (used by nalutils.c's NAL
emulation-prevention encoder path — dead code for the parse-only
libva backend).

src/meson.build — added the 5 new .c source files and 10 new .h
headers; added include_directories('h265_parser') to the include path
so the vendored files' '#include <gst/base/...>' style references
resolve to the stub headers + actual vendored files in the local
tree.

Build verified: ninja -C build produces v4l2_request_drv_video.so
(682 KB, up from 485 KB pre-vendor — the +200 KB is the vendored
parser code). nm shows gst_h265_parse_sps, gst_h265_parse_sps_ext,
gst_h265_parser_identify_nalu, and the other functions we need for
Step 4 are present in the binary.

Two #warning messages from gsth265parser.h about API stability are
upstream-intentional and harmless ('The H.265 parsing library is
unstable API and may change in future').

This commit completes Step 2 of ampere-kernel-decoders iter2 Phase 6.
Backend remains functionally identical to pre-iter2 — the new code
compiles + links but is not yet called from h265_set_controls (that's
Step 4). Existing 5 codecs continue to work as before.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-17 09:49:06 +00:00

270 lines
7.7 KiB
C

/* Gstreamer
* Copyright (C) <2011> Intel Corporation
* Copyright (C) <2011> Collabora Ltd.
* Copyright (C) <2011> Thibault Saunier <thibault.saunier@collabora.com>
*
* Some bits C-c,C-v'ed and s/4/3 from h264parse and videoparsers/h264parse.c:
* Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
* Copyright (C) <2010> Collabora Multimedia
* Copyright (C) <2010> Nokia Corporation
*
* (C) 2005 Michal Benes <michal.benes@itonis.tv>
* (C) 2008 Wim Taymans <wim.taymans@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* Common code for NAL parsing from h264 and h265 parsers.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <gst/base/gstbytereader.h>
#include <gst/base/gstbitreader.h>
#include <gst/base/gstbitwriter.h>
typedef struct
{
const guint8 *data;
guint size;
guint n_epb; /* Number of emulation prevention bytes */
guint byte; /* Byte position */
guint bits_in_cache; /* bitpos in the cache of next bit */
guint8 first_byte;
guint32 epb_cache; /* cache 3 bytes to check emulation prevention bytes */
guint64 cache; /* cached bytes */
} NalReader;
typedef struct
{
GstBitWriter bw;
guint nal_prefix_size;
gboolean packetized;
} NalWriter;
G_GNUC_INTERNAL
void nal_reader_init (NalReader * nr, const guint8 * data, guint size);
G_GNUC_INTERNAL
gboolean nal_reader_read (NalReader * nr, guint nbits);
G_GNUC_INTERNAL
gboolean nal_reader_skip (NalReader * nr, guint nbits);
G_GNUC_INTERNAL
gboolean nal_reader_skip_long (NalReader * nr, guint nbits);
G_GNUC_INTERNAL
guint nal_reader_get_pos (const NalReader * nr);
G_GNUC_INTERNAL
guint nal_reader_get_remaining (const NalReader * nr);
G_GNUC_INTERNAL
guint nal_reader_get_epb_count (const NalReader * nr);
G_GNUC_INTERNAL
gboolean nal_reader_is_byte_aligned (NalReader * nr);
G_GNUC_INTERNAL
gboolean nal_reader_has_more_data (NalReader * nr);
#define NAL_READER_READ_BITS_H(bits) \
G_GNUC_INTERNAL \
gboolean nal_reader_get_bits_uint##bits (NalReader *nr, guint##bits *val, guint nbits)
NAL_READER_READ_BITS_H (8);
NAL_READER_READ_BITS_H (16);
NAL_READER_READ_BITS_H (32);
#define NAL_READER_PEEK_BITS_H(bits) \
G_GNUC_INTERNAL \
gboolean nal_reader_peek_bits_uint##bits (const NalReader *nr, guint##bits *val, guint nbits)
NAL_READER_PEEK_BITS_H (8);
G_GNUC_INTERNAL
gboolean nal_reader_get_ue (NalReader * nr, guint32 * val);
G_GNUC_INTERNAL
gboolean nal_reader_get_se (NalReader * nr, gint32 * val);
#define CHECK_ALLOWED_MAX_WITH_DEBUG(dbg, val, max) { \
if (val > max) { \
GST_WARNING ("value for '" dbg "' greater than max. value: %d, max %d", \
val, max); \
goto error; \
} \
}
#define CHECK_ALLOWED_MAX(val, max) \
CHECK_ALLOWED_MAX_WITH_DEBUG (G_STRINGIFY (val), val, max)
#define CHECK_ALLOWED_WITH_DEBUG(dbg, val, min, max) { \
if (val < min || val > max) { \
GST_WARNING ("value for '" dbg "' not in allowed range. value: %d, range %d-%d", \
val, min, max); \
goto error; \
} \
}
#define CHECK_ALLOWED(val, min, max) \
CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), val, min, max)
#define READ_UINT8(nr, val, nbits) { \
if (!nal_reader_get_bits_uint8 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint8 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT16(nr, val, nbits) { \
if (!nal_reader_get_bits_uint16 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint16 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT32(nr, val, nbits) { \
if (!nal_reader_get_bits_uint32 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UINT64(nr, val, nbits) { \
if (!nal_reader_get_bits_uint64 (nr, &val, nbits)) { \
GST_WARNING ("failed to read uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define READ_UE(nr, val) { \
if (!nal_reader_get_ue (nr, &val)) { \
GST_WARNING ("failed to read UE for '" G_STRINGIFY (val) "'"); \
goto error; \
} \
}
#define READ_UE_ALLOWED(nr, val, min, max) { \
guint32 tmp; \
READ_UE (nr, tmp); \
CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), tmp, min, max); \
val = tmp; \
}
#define READ_UE_MAX(nr, val, max) { \
guint32 tmp; \
READ_UE (nr, tmp); \
CHECK_ALLOWED_MAX_WITH_DEBUG (G_STRINGIFY (val), tmp, max); \
val = tmp; \
}
#define READ_SE(nr, val) { \
if (!nal_reader_get_se (nr, &val)) { \
GST_WARNING ("failed to read SE for '" G_STRINGIFY (val) "'"); \
goto error; \
} \
}
#define READ_SE_ALLOWED(nr, val, min, max) { \
gint32 tmp; \
READ_SE (nr, tmp); \
CHECK_ALLOWED_WITH_DEBUG (G_STRINGIFY (val), tmp, min, max); \
val = tmp; \
}
G_GNUC_INTERNAL
gint scan_for_start_codes (const guint8 * data, guint size);
G_GNUC_INTERNAL
void nal_writer_init (NalWriter * nw, guint nal_prefix_size, gboolean packetized);
G_GNUC_INTERNAL
void nal_writer_reset (NalWriter * nw);
G_GNUC_INTERNAL
gboolean nal_writer_do_rbsp_trailing_bits (NalWriter * nw);
G_GNUC_INTERNAL
GstMemory * nal_writer_reset_and_get_memory (NalWriter * nw);
G_GNUC_INTERNAL
guint8 * nal_writer_reset_and_get_data (NalWriter * nw, guint32 * ret_size);
G_GNUC_INTERNAL
gboolean nal_writer_put_bits_uint8 (NalWriter * nw, guint8 value, guint nbits);
G_GNUC_INTERNAL
gboolean nal_writer_put_bits_uint16 (NalWriter * nw, guint16 value, guint nbits);
G_GNUC_INTERNAL
gboolean nal_writer_put_bits_uint32 (NalWriter * nw, guint32 value, guint nbits);
G_GNUC_INTERNAL
gboolean nal_writer_put_bytes (NalWriter * nw, const guint8 * data, guint nbytes);
G_GNUC_INTERNAL
gboolean nal_writer_put_ue (NalWriter * nw, guint32 value);
G_GNUC_INTERNAL
gboolean count_exp_golomb_bits (guint32 value, guint * leading_zeros, guint * rest);
#define WRITE_UINT8(nw, val, nbits) { \
if (!nal_writer_put_bits_uint8 (nw, val, nbits)) { \
GST_WARNING ("failed to write uint8 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define WRITE_UINT16(nw, val, nbits) { \
if (!nal_writer_put_bits_uint16 (nw, val, nbits)) { \
GST_WARNING ("failed to write uint16 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define WRITE_UINT32(nw, val, nbits) { \
if (!nal_writer_put_bits_uint32 (nw, val, nbits)) { \
GST_WARNING ("failed to write uint32 for '" G_STRINGIFY (val) "', nbits: %d", nbits); \
goto error; \
} \
}
#define WRITE_BYTES(nw, data, nbytes) { \
if (!nal_writer_put_bytes (nw, data, nbytes)) { \
GST_WARNING ("failed to write bytes for '" G_STRINGIFY (val) "', nbits: %d", nbytes); \
goto error; \
} \
}
#define WRITE_UE(nw, val) { \
if (!nal_writer_put_ue (nw, val)) { \
GST_WARNING ("failed to write ue for '" G_STRINGIFY (val) "'"); \
goto error; \
} \
}
static inline guint32 div_ceil (guint32 a, guint32 b)
{
/* http://blog.pkh.me/p/36-figuring-out-round%2C-floor-and-ceil-with-integer-division.html */
g_assert (b > 0);
return a / b + (a % b > 0);
}