/* * Copyright © 2010 Mozilla Foundation * * This program is made available under an ISC-style license. See the * accompanying file LICENSE for details. */ #include #include #include #include "nestegg/halloc/halloc.h" #include "nestegg/include/nestegg/nestegg.h" /* EBML Elements */ #define ID_EBML 0x1a45dfa3 #define ID_EBML_VERSION 0x4286 #define ID_EBML_READ_VERSION 0x42f7 #define ID_EBML_MAX_ID_LENGTH 0x42f2 #define ID_EBML_MAX_SIZE_LENGTH 0x42f3 #define ID_DOCTYPE 0x4282 #define ID_DOCTYPE_VERSION 0x4287 #define ID_DOCTYPE_READ_VERSION 0x4285 /* Global Elements */ #define ID_VOID 0xec #define ID_CRC32 0xbf /* WebMedia Elements */ #define ID_SEGMENT 0x18538067 /* Seek Head Elements */ #define ID_SEEK_HEAD 0x114d9b74 #define ID_SEEK 0x4dbb #define ID_SEEK_ID 0x53ab #define ID_SEEK_POSITION 0x53ac /* Info Elements */ #define ID_INFO 0x1549a966 #define ID_TIMECODE_SCALE 0x2ad7b1 #define ID_DURATION 0x4489 /* Cluster Elements */ #define ID_CLUSTER 0x1f43b675 #define ID_TIMECODE 0xe7 #define ID_BLOCK_GROUP 0xa0 #define ID_SIMPLE_BLOCK 0xa3 /* BlockGroup Elements */ #define ID_BLOCK 0xa1 #define ID_BLOCK_DURATION 0x9b #define ID_REFERENCE_BLOCK 0xfb /* Tracks Elements */ #define ID_TRACKS 0x1654ae6b #define ID_TRACK_ENTRY 0xae #define ID_TRACK_NUMBER 0xd7 #define ID_TRACK_UID 0x73c5 #define ID_TRACK_TYPE 0x83 #define ID_FLAG_ENABLED 0xb9 #define ID_FLAG_DEFAULT 0x88 #define ID_FLAG_LACING 0x9c #define ID_TRACK_TIMECODE_SCALE 0x23314f #define ID_LANGUAGE 0x22b59c #define ID_CODEC_ID 0x86 #define ID_CODEC_PRIVATE 0x63a2 /* Video Elements */ #define ID_VIDEO 0xe0 #define ID_PIXEL_WIDTH 0xb0 #define ID_PIXEL_HEIGHT 0xba #define ID_PIXEL_CROP_BOTTOM 0x54aa #define ID_PIXEL_CROP_TOP 0x54bb #define ID_PIXEL_CROP_LEFT 0x54cc #define ID_PIXEL_CROP_RIGHT 0x54dd #define ID_DISPLAY_WIDTH 0x54b0 #define ID_DISPLAY_HEIGHT 0x54ba /* Audio Elements */ #define ID_AUDIO 0xe1 #define ID_SAMPLING_FREQUENCY 0xb5 #define ID_CHANNELS 0x9f #define ID_BIT_DEPTH 0x6264 /* Cues Elements */ #define ID_CUES 0x1c53bb6b #define ID_CUE_POINT 0xbb #define ID_CUE_TIME 0xb3 #define ID_CUE_TRACK_POSITIONS 0xb7 #define ID_CUE_TRACK 0xf7 #define ID_CUE_CLUSTER_POSITION 0xf1 #define ID_CUE_BLOCK_NUMBER 0x5378 /* EBML Types */ enum ebml_type_enum { TYPE_UNKNOWN, TYPE_MASTER, TYPE_UINT, TYPE_FLOAT, TYPE_INT, TYPE_STRING, TYPE_BINARY }; #define LIMIT_STRING (1 << 20) #define LIMIT_BINARY (1 << 24) #define LIMIT_BLOCK (1 << 30) #define LIMIT_FRAME (1 << 28) /* Field Flags */ #define DESC_FLAG_NONE 0 #define DESC_FLAG_MULTI (1 << 0) #define DESC_FLAG_SUSPEND (1 << 1) #define DESC_FLAG_OFFSET (1 << 2) /* Block Header Flags */ #define BLOCK_FLAGS_LACING 6 /* Lacing Constants */ #define LACING_NONE 0 #define LACING_XIPH 1 #define LACING_FIXED 2 #define LACING_EBML 3 /* Track Types */ #define TRACK_TYPE_VIDEO 1 #define TRACK_TYPE_AUDIO 2 /* Track IDs */ #define TRACK_ID_VP8 "V_VP8" #define TRACK_ID_VP9 "V_VP9" #define TRACK_ID_VORBIS "A_VORBIS" enum vint_mask { MASK_NONE, MASK_FIRST_BIT }; struct ebml_binary { unsigned char * data; size_t length; }; struct ebml_list_node { struct ebml_list_node * next; uint64_t id; void * data; }; struct ebml_list { struct ebml_list_node * head; struct ebml_list_node * tail; }; struct ebml_type { union ebml_value { uint64_t u; double f; int64_t i; char * s; struct ebml_binary b; } v; enum ebml_type_enum type; int read; }; /* EBML Definitions */ struct ebml { struct ebml_type ebml_version; struct ebml_type ebml_read_version; struct ebml_type ebml_max_id_length; struct ebml_type ebml_max_size_length; struct ebml_type doctype; struct ebml_type doctype_version; struct ebml_type doctype_read_version; }; /* Matroksa Definitions */ struct seek { struct ebml_type id; struct ebml_type position; }; struct seek_head { struct ebml_list seek; }; struct info { struct ebml_type timecode_scale; struct ebml_type duration; }; struct block_group { struct ebml_type duration; struct ebml_type reference_block; }; struct cluster { struct ebml_type timecode; struct ebml_list block_group; }; struct video { struct ebml_type pixel_width; struct ebml_type pixel_height; struct ebml_type pixel_crop_bottom; struct ebml_type pixel_crop_top; struct ebml_type pixel_crop_left; struct ebml_type pixel_crop_right; struct ebml_type display_width; struct ebml_type display_height; }; struct audio { struct ebml_type sampling_frequency; struct ebml_type channels; struct ebml_type bit_depth; }; struct track_entry { struct ebml_type number; struct ebml_type uid; struct ebml_type type; struct ebml_type flag_enabled; struct ebml_type flag_default; struct ebml_type flag_lacing; struct ebml_type track_timecode_scale; struct ebml_type language; struct ebml_type codec_id; struct ebml_type codec_private; struct video video; struct audio audio; }; struct tracks { struct ebml_list track_entry; }; struct cue_track_positions { struct ebml_type track; struct ebml_type cluster_position; struct ebml_type block_number; }; struct cue_point { struct ebml_type time; struct ebml_list cue_track_positions; }; struct cues { struct ebml_list cue_point; }; struct segment { struct ebml_list seek_head; struct info info; struct ebml_list cluster; struct tracks tracks; struct cues cues; }; /* Misc. */ struct pool_ctx { char dummy; }; struct list_node { struct list_node * previous; struct ebml_element_desc * node; unsigned char * data; }; struct saved_state { int64_t stream_offset; struct list_node * ancestor; uint64_t last_id; uint64_t last_size; }; struct frame { unsigned char * data; size_t length; struct frame * next; }; /* Public (opaque) Structures */ struct nestegg { nestegg_io * io; nestegg_log log; struct pool_ctx * alloc_pool; uint64_t last_id; uint64_t last_size; struct list_node * ancestor; struct ebml ebml; struct segment segment; int64_t segment_offset; unsigned int track_count; }; struct nestegg_packet { uint64_t track; uint64_t timecode; struct frame * frame; }; /* Element Descriptor */ struct ebml_element_desc { char const * name; uint64_t id; enum ebml_type_enum type; size_t offset; unsigned int flags; struct ebml_element_desc * children; size_t size; size_t data_offset; }; #define E_FIELD(ID, TYPE, STRUCT, FIELD) \ { #ID, ID, TYPE, offsetof(STRUCT, FIELD), DESC_FLAG_NONE, NULL, 0, 0 } #define E_MASTER(ID, TYPE, STRUCT, FIELD) \ { #ID, ID, TYPE, offsetof(STRUCT, FIELD), DESC_FLAG_MULTI, ne_ ## FIELD ## _elements, \ sizeof(struct FIELD), 0 } #define E_SINGLE_MASTER_O(ID, TYPE, STRUCT, FIELD) \ { #ID, ID, TYPE, offsetof(STRUCT, FIELD), DESC_FLAG_OFFSET, ne_ ## FIELD ## _elements, 0, \ offsetof(STRUCT, FIELD ## _offset) } #define E_SINGLE_MASTER(ID, TYPE, STRUCT, FIELD) \ { #ID, ID, TYPE, offsetof(STRUCT, FIELD), DESC_FLAG_NONE, ne_ ## FIELD ## _elements, 0, 0 } #define E_SUSPEND(ID, TYPE) \ { #ID, ID, TYPE, 0, DESC_FLAG_SUSPEND, NULL, 0, 0 } #define E_LAST \ { NULL, 0, 0, 0, DESC_FLAG_NONE, NULL, 0, 0 } /* EBML Element Lists */ static struct ebml_element_desc ne_ebml_elements[] = { E_FIELD(ID_EBML_VERSION, TYPE_UINT, struct ebml, ebml_version), E_FIELD(ID_EBML_READ_VERSION, TYPE_UINT, struct ebml, ebml_read_version), E_FIELD(ID_EBML_MAX_ID_LENGTH, TYPE_UINT, struct ebml, ebml_max_id_length), E_FIELD(ID_EBML_MAX_SIZE_LENGTH, TYPE_UINT, struct ebml, ebml_max_size_length), E_FIELD(ID_DOCTYPE, TYPE_STRING, struct ebml, doctype), E_FIELD(ID_DOCTYPE_VERSION, TYPE_UINT, struct ebml, doctype_version), E_FIELD(ID_DOCTYPE_READ_VERSION, TYPE_UINT, struct ebml, doctype_read_version), E_LAST }; /* WebMedia Element Lists */ static struct ebml_element_desc ne_seek_elements[] = { E_FIELD(ID_SEEK_ID, TYPE_BINARY, struct seek, id), E_FIELD(ID_SEEK_POSITION, TYPE_UINT, struct seek, position), E_LAST }; static struct ebml_element_desc ne_seek_head_elements[] = { E_MASTER(ID_SEEK, TYPE_MASTER, struct seek_head, seek), E_LAST }; static struct ebml_element_desc ne_info_elements[] = { E_FIELD(ID_TIMECODE_SCALE, TYPE_UINT, struct info, timecode_scale), E_FIELD(ID_DURATION, TYPE_FLOAT, struct info, duration), E_LAST }; static struct ebml_element_desc ne_block_group_elements[] = { E_SUSPEND(ID_BLOCK, TYPE_BINARY), E_FIELD(ID_BLOCK_DURATION, TYPE_UINT, struct block_group, duration), E_FIELD(ID_REFERENCE_BLOCK, TYPE_INT, struct block_group, reference_block), E_LAST }; static struct ebml_element_desc ne_cluster_elements[] = { E_FIELD(ID_TIMECODE, TYPE_UINT, struct cluster, timecode), E_MASTER(ID_BLOCK_GROUP, TYPE_MASTER, struct cluster, block_group), E_SUSPEND(ID_SIMPLE_BLOCK, TYPE_BINARY), E_LAST }; static struct ebml_element_desc ne_video_elements[] = { E_FIELD(ID_PIXEL_WIDTH, TYPE_UINT, struct video, pixel_width), E_FIELD(ID_PIXEL_HEIGHT, TYPE_UINT, struct video, pixel_height), E_FIELD(ID_PIXEL_CROP_BOTTOM, TYPE_UINT, struct video, pixel_crop_bottom), E_FIELD(ID_PIXEL_CROP_TOP, TYPE_UINT, struct video, pixel_crop_top), E_FIELD(ID_PIXEL_CROP_LEFT, TYPE_UINT, struct video, pixel_crop_left), E_FIELD(ID_PIXEL_CROP_RIGHT, TYPE_UINT, struct video, pixel_crop_right), E_FIELD(ID_DISPLAY_WIDTH, TYPE_UINT, struct video, display_width), E_FIELD(ID_DISPLAY_HEIGHT, TYPE_UINT, struct video, display_height), E_LAST }; static struct ebml_element_desc ne_audio_elements[] = { E_FIELD(ID_SAMPLING_FREQUENCY, TYPE_FLOAT, struct audio, sampling_frequency), E_FIELD(ID_CHANNELS, TYPE_UINT, struct audio, channels), E_FIELD(ID_BIT_DEPTH, TYPE_UINT, struct audio, bit_depth), E_LAST }; static struct ebml_element_desc ne_track_entry_elements[] = { E_FIELD(ID_TRACK_NUMBER, TYPE_UINT, struct track_entry, number), E_FIELD(ID_TRACK_UID, TYPE_UINT, struct track_entry, uid), E_FIELD(ID_TRACK_TYPE, TYPE_UINT, struct track_entry, type), E_FIELD(ID_FLAG_ENABLED, TYPE_UINT, struct track_entry, flag_enabled), E_FIELD(ID_FLAG_DEFAULT, TYPE_UINT, struct track_entry, flag_default), E_FIELD(ID_FLAG_LACING, TYPE_UINT, struct track_entry, flag_lacing), E_FIELD(ID_TRACK_TIMECODE_SCALE, TYPE_FLOAT, struct track_entry, track_timecode_scale), E_FIELD(ID_LANGUAGE, TYPE_STRING, struct track_entry, language), E_FIELD(ID_CODEC_ID, TYPE_STRING, struct track_entry, codec_id), E_FIELD(ID_CODEC_PRIVATE, TYPE_BINARY, struct track_entry, codec_private), E_SINGLE_MASTER(ID_VIDEO, TYPE_MASTER, struct track_entry, video), E_SINGLE_MASTER(ID_AUDIO, TYPE_MASTER, struct track_entry, audio), E_LAST }; static struct ebml_element_desc ne_tracks_elements[] = { E_MASTER(ID_TRACK_ENTRY, TYPE_MASTER, struct tracks, track_entry), E_LAST }; static struct ebml_element_desc ne_cue_track_positions_elements[] = { E_FIELD(ID_CUE_TRACK, TYPE_UINT, struct cue_track_positions, track), E_FIELD(ID_CUE_CLUSTER_POSITION, TYPE_UINT, struct cue_track_positions, cluster_position), E_FIELD(ID_CUE_BLOCK_NUMBER, TYPE_UINT, struct cue_track_positions, block_number), E_LAST }; static struct ebml_element_desc ne_cue_point_elements[] = { E_FIELD(ID_CUE_TIME, TYPE_UINT, struct cue_point, time), E_MASTER(ID_CUE_TRACK_POSITIONS, TYPE_MASTER, struct cue_point, cue_track_positions), E_LAST }; static struct ebml_element_desc ne_cues_elements[] = { E_MASTER(ID_CUE_POINT, TYPE_MASTER, struct cues, cue_point), E_LAST }; static struct ebml_element_desc ne_segment_elements[] = { E_MASTER(ID_SEEK_HEAD, TYPE_MASTER, struct segment, seek_head), E_SINGLE_MASTER(ID_INFO, TYPE_MASTER, struct segment, info), E_MASTER(ID_CLUSTER, TYPE_MASTER, struct segment, cluster), E_SINGLE_MASTER(ID_TRACKS, TYPE_MASTER, struct segment, tracks), E_SINGLE_MASTER(ID_CUES, TYPE_MASTER, struct segment, cues), E_LAST }; static struct ebml_element_desc ne_top_level_elements[] = { E_SINGLE_MASTER(ID_EBML, TYPE_MASTER, nestegg, ebml), E_SINGLE_MASTER_O(ID_SEGMENT, TYPE_MASTER, nestegg, segment), E_LAST }; #undef E_FIELD #undef E_MASTER #undef E_SINGLE_MASTER_O #undef E_SINGLE_MASTER #undef E_SUSPEND #undef E_LAST static struct pool_ctx * ne_pool_init(void) { struct pool_ctx * pool; pool = h_malloc(sizeof(*pool)); if (!pool) abort(); return pool; } static void ne_pool_destroy(struct pool_ctx * pool) { h_free(pool); } static void * ne_pool_alloc(size_t size, struct pool_ctx * pool) { void * p; p = h_malloc(size); if (!p) abort(); hattach(p, pool); memset(p, 0, size); return p; } static void * ne_alloc(size_t size) { void * p; p = calloc(1, size); if (!p) abort(); return p; } static int ne_io_read(nestegg_io * io, void * buffer, size_t length) { return io->read(buffer, length, io->userdata); } static int ne_io_seek(nestegg_io * io, int64_t offset, int whence) { return io->seek(offset, whence, io->userdata); } static int ne_io_read_skip(nestegg_io * io, size_t length) { size_t get; unsigned char buf[8192]; int r = 1; while (length > 0) { get = length < sizeof(buf) ? length : sizeof(buf); r = ne_io_read(io, buf, get); if (r != 1) break; length -= get; } return r; } static int64_t ne_io_tell(nestegg_io * io) { return io->tell(io->userdata); } static int ne_bare_read_vint(nestegg_io * io, uint64_t * value, uint64_t * length, enum vint_mask maskflag) { int r; unsigned char b; size_t maxlen = 8; unsigned int count = 1, mask = 1 << 7; r = ne_io_read(io, &b, 1); if (r != 1) return r; while (count < maxlen) { if ((b & mask) != 0) break; mask >>= 1; count += 1; } if (length) *length = count; *value = b; if (maskflag == MASK_FIRST_BIT) *value = b & ~mask; while (--count) { r = ne_io_read(io, &b, 1); if (r != 1) return r; *value <<= 8; *value |= b; } return 1; } static int ne_read_id(nestegg_io * io, uint64_t * value, uint64_t * length) { return ne_bare_read_vint(io, value, length, MASK_NONE); } static int ne_read_vint(nestegg_io * io, uint64_t * value, uint64_t * length) { return ne_bare_read_vint(io, value, length, MASK_FIRST_BIT); } static int ne_read_svint(nestegg_io * io, int64_t * value, uint64_t * length) { int r; uint64_t uvalue; uint64_t ulength; int64_t svint_subtr[] = { 0x3f, 0x1fff, 0xfffff, 0x7ffffff, 0x3ffffffffLL, 0x1ffffffffffLL, 0xffffffffffffLL, 0x7fffffffffffffLL }; r = ne_bare_read_vint(io, &uvalue, &ulength, MASK_FIRST_BIT); if (r != 1) return r; *value = uvalue - svint_subtr[ulength - 1]; if (length) *length = ulength; return r; } static int ne_read_uint(nestegg_io * io, uint64_t * val, uint64_t length) { unsigned char b; int r; if (length == 0 || length > 8) return -1; r = ne_io_read(io, &b, 1); if (r != 1) return r; *val = b; while (--length) { r = ne_io_read(io, &b, 1); if (r != 1) return r; *val <<= 8; *val |= b; } return 1; } static int ne_read_int(nestegg_io * io, int64_t * val, uint64_t length) { int r; uint64_t uval, base; r = ne_read_uint(io, &uval, length); if (r != 1) return r; if (length < sizeof(int64_t)) { base = 1; base <<= length * 8 - 1; if (uval >= base) { base = 1; base <<= length * 8; } else { base = 0; } *val = uval - base; } else { *val = (int64_t) uval; } return 1; } static int ne_read_float(nestegg_io * io, double * val, uint64_t length) { union { uint64_t u; float f; double d; } value; int r; /* length == 10 not implemented */ if (length != 4 && length != 8) return -1; r = ne_read_uint(io, &value.u, length); if (r != 1) return r; if (length == 4) *val = value.f; else *val = value.d; return 1; } static int ne_read_string(nestegg * ctx, char ** val, uint64_t length) { char * str; int r; if (length == 0 || length > LIMIT_STRING) return -1; str = ne_pool_alloc(length + 1, ctx->alloc_pool); r = ne_io_read(ctx->io, (unsigned char *) str, length); if (r != 1) return r; str[length] = '\0'; *val = str; return 1; } static int ne_read_binary(nestegg * ctx, struct ebml_binary * val, uint64_t length) { if (length == 0 || length > LIMIT_BINARY) return -1; val->data = ne_pool_alloc(length, ctx->alloc_pool); val->length = length; return ne_io_read(ctx->io, val->data, length); } static int ne_get_uint(struct ebml_type type, uint64_t * value) { if (!type.read) return -1; assert(type.type == TYPE_UINT); *value = type.v.u; return 0; } static int ne_get_float(struct ebml_type type, double * value) { if (!type.read) return -1; assert(type.type == TYPE_FLOAT); *value = type.v.f; return 0; } static int ne_get_string(struct ebml_type type, char ** value) { if (!type.read) return -1; assert(type.type == TYPE_STRING); *value = type.v.s; return 0; } static int ne_get_binary(struct ebml_type type, struct ebml_binary * value) { if (!type.read) return -1; assert(type.type == TYPE_BINARY); *value = type.v.b; return 0; } static int ne_is_ancestor_element(uint64_t id, struct list_node * ancestor) { struct ebml_element_desc * element; for (; ancestor; ancestor = ancestor->previous) for (element = ancestor->node; element->id; ++element) if (element->id == id) return 1; return 0; } static struct ebml_element_desc * ne_find_element(uint64_t id, struct ebml_element_desc * elements) { struct ebml_element_desc * element; for (element = elements; element->id; ++element) if (element->id == id) return element; return NULL; } static void ne_ctx_push(nestegg * ctx, struct ebml_element_desc * ancestor, void * data) { struct list_node * item; item = ne_alloc(sizeof(*item)); item->previous = ctx->ancestor; item->node = ancestor; item->data = data; ctx->ancestor = item; } static void ne_ctx_pop(nestegg * ctx) { struct list_node * item; item = ctx->ancestor; ctx->ancestor = item->previous; free(item); } static int ne_ctx_save(nestegg * ctx, struct saved_state * s) { s->stream_offset = ne_io_tell(ctx->io); if (s->stream_offset < 0) return -1; s->ancestor = ctx->ancestor; s->last_id = ctx->last_id; s->last_size = ctx->last_size; return 0; } static int ne_ctx_restore(nestegg * ctx, struct saved_state * s) { int r; r = ne_io_seek(ctx->io, s->stream_offset, NESTEGG_SEEK_SET); if (r != 0) return -1; ctx->ancestor = s->ancestor; ctx->last_id = s->last_id; ctx->last_size = s->last_size; return 0; } static int ne_peek_element(nestegg * ctx, uint64_t * id, uint64_t * size) { int r; if (ctx->last_id && ctx->last_size) { if (id) *id = ctx->last_id; if (size) *size = ctx->last_size; return 1; } r = ne_read_id(ctx->io, &ctx->last_id, NULL); if (r != 1) return r; r = ne_read_vint(ctx->io, &ctx->last_size, NULL); if (r != 1) return r; if (id) *id = ctx->last_id; if (size) *size = ctx->last_size; return 1; } static int ne_read_element(nestegg * ctx, uint64_t * id, uint64_t * size) { int r; r = ne_peek_element(ctx, id, size); if (r != 1) return r; ctx->last_id = 0; ctx->last_size = 0; return 1; } static void ne_read_master(nestegg * ctx, struct ebml_element_desc * desc) { struct ebml_list * list; struct ebml_list_node * node, * oldtail; assert(desc->type == TYPE_MASTER && desc->flags & DESC_FLAG_MULTI); ctx->log(ctx, NESTEGG_LOG_DEBUG, "multi master element %llx (%s)", desc->id, desc->name); list = (struct ebml_list *) (ctx->ancestor->data + desc->offset); node = ne_pool_alloc(sizeof(*node), ctx->alloc_pool); node->id = desc->id; node->data = ne_pool_alloc(desc->size, ctx->alloc_pool); oldtail = list->tail; if (oldtail) oldtail->next = node; list->tail = node; if (!list->head) list->head = node; ctx->log(ctx, NESTEGG_LOG_DEBUG, " -> using data %p", node->data); ne_ctx_push(ctx, desc->children, node->data); } static void ne_read_single_master(nestegg * ctx, struct ebml_element_desc * desc) { assert(desc->type == TYPE_MASTER && !(desc->flags & DESC_FLAG_MULTI)); ctx->log(ctx, NESTEGG_LOG_DEBUG, "single master element %llx (%s)", desc->id, desc->name); ctx->log(ctx, NESTEGG_LOG_DEBUG, " -> using data %p (%u)", ctx->ancestor->data + desc->offset, desc->offset); ne_ctx_push(ctx, desc->children, ctx->ancestor->data + desc->offset); } static int ne_read_simple(nestegg * ctx, struct ebml_element_desc * desc, size_t length) { struct ebml_type * storage; int r; storage = (struct ebml_type *) (ctx->ancestor->data + desc->offset); if (storage->read) { ctx->log(ctx, NESTEGG_LOG_DEBUG, "element %llx (%s) already read, skipping", desc->id, desc->name); return 0; } storage->type = desc->type; ctx->log(ctx, NESTEGG_LOG_DEBUG, "element %llx (%s) -> %p (%u)", desc->id, desc->name, storage, desc->offset); r = -1; switch (desc->type) { case TYPE_UINT: r = ne_read_uint(ctx->io, &storage->v.u, length); break; case TYPE_FLOAT: r = ne_read_float(ctx->io, &storage->v.f, length); break; case TYPE_INT: r = ne_read_int(ctx->io, &storage->v.i, length); break; case TYPE_STRING: r = ne_read_string(ctx, &storage->v.s, length); break; case TYPE_BINARY: r = ne_read_binary(ctx, &storage->v.b, length); break; case TYPE_MASTER: case TYPE_UNKNOWN: assert(0); break; } if (r == 1) storage->read = 1; return r; } static int ne_parse(nestegg * ctx, struct ebml_element_desc * top_level) { int r; int64_t * data_offset; uint64_t id, size; struct ebml_element_desc * element; /* loop until we need to return: - hit suspend point - parse complete - error occurred */ /* loop over elements at current level reading them if sublevel found, push ctx onto stack and continue if sublevel ended, pop ctx off stack and continue */ if (!ctx->ancestor) return -1; for (;;) { r = ne_peek_element(ctx, &id, &size); if (r != 1) break; element = ne_find_element(id, ctx->ancestor->node); if (element) { if (element->flags & DESC_FLAG_SUSPEND) { assert(element->type == TYPE_BINARY); ctx->log(ctx, NESTEGG_LOG_DEBUG, "suspend parse at %llx", id); r = 1; break; } r = ne_read_element(ctx, &id, &size); if (r != 1) break; if (element->flags & DESC_FLAG_OFFSET) { data_offset = (int64_t *) (ctx->ancestor->data + element->data_offset); *data_offset = ne_io_tell(ctx->io); if (*data_offset < 0) { r = -1; break; } } if (element->type == TYPE_MASTER) { if (element->flags & DESC_FLAG_MULTI) ne_read_master(ctx, element); else ne_read_single_master(ctx, element); continue; } else { r = ne_read_simple(ctx, element, size); if (r < 0) break; } } else if (ne_is_ancestor_element(id, ctx->ancestor->previous)) { ctx->log(ctx, NESTEGG_LOG_DEBUG, "parent element %llx", id); if (top_level && ctx->ancestor->node == top_level) { ctx->log(ctx, NESTEGG_LOG_DEBUG, "*** parse about to back up past top_level"); r = 1; break; } ne_ctx_pop(ctx); } else { r = ne_read_element(ctx, &id, &size); if (r != 1) break; if (id != ID_VOID && id != ID_CRC32) ctx->log(ctx, NESTEGG_LOG_DEBUG, "unknown element %llx", id); r = ne_io_read_skip(ctx->io, size); if (r != 1) break; } } if (r != 1) while (ctx->ancestor) ne_ctx_pop(ctx); return r; } static uint64_t ne_xiph_lace_value(unsigned char ** np) { uint64_t lace; uint64_t value; unsigned char * p = *np; lace = *p++; value = lace; while (lace == 255) { lace = *p++; value += lace; } *np = p; return value; } static int ne_read_xiph_lace_value(nestegg_io * io, uint64_t * value, size_t * consumed) { int r; uint64_t lace; r = ne_read_uint(io, &lace, 1); if (r != 1) return r; *consumed += 1; *value = lace; while (lace == 255) { r = ne_read_uint(io, &lace, 1); if (r != 1) return r; *consumed += 1; *value += lace; } return 1; } static int ne_read_xiph_lacing(nestegg_io * io, size_t block, size_t * read, uint64_t n, uint64_t * sizes) { int r; size_t i = 0; uint64_t sum = 0; while (--n) { r = ne_read_xiph_lace_value(io, &sizes[i], read); if (r != 1) return r; sum += sizes[i]; i += 1; } if (*read + sum > block) return -1; /* last frame is the remainder of the block */ sizes[i] = block - *read - sum; return 1; } static int ne_read_ebml_lacing(nestegg_io * io, size_t block, size_t * read, uint64_t n, uint64_t * sizes) { int r; uint64_t lace, sum, length; int64_t slace; size_t i = 0; r = ne_read_vint(io, &lace, &length); if (r != 1) return r; *read += length; sizes[i] = lace; sum = sizes[i]; i += 1; n -= 1; while (--n) { r = ne_read_svint(io, &slace, &length); if (r != 1) return r; *read += length; sizes[i] = sizes[i - 1] + slace; sum += sizes[i]; i += 1; } if (*read + sum > block) return -1; /* last frame is the remainder of the block */ sizes[i] = block - *read - sum; return 1; } static uint64_t ne_get_timecode_scale(nestegg * ctx) { uint64_t scale; if (ne_get_uint(ctx->segment.info.timecode_scale, &scale) != 0) scale = 1000000; return scale; } static struct track_entry * ne_find_track_entry(nestegg * ctx, unsigned int track) { struct ebml_list_node * node; unsigned int tracks = 0; node = ctx->segment.tracks.track_entry.head; while (node) { assert(node->id == ID_TRACK_ENTRY); if (track == tracks) return node->data; tracks += 1; node = node->next; } return NULL; } static int ne_read_block(nestegg * ctx, uint64_t block_id, uint64_t block_size, nestegg_packet ** data) { int r; int64_t timecode, abs_timecode; nestegg_packet * pkt; struct cluster * cluster; struct frame * f, * last; struct track_entry * entry; double track_scale; uint64_t track, length, frame_sizes[256], cluster_tc, flags, frames, tc_scale, total; unsigned int i, lacing; size_t consumed = 0; *data = NULL; if (block_size > LIMIT_BLOCK) return -1; r = ne_read_vint(ctx->io, &track, &length); if (r != 1) return r; if (track == 0 || track > ctx->track_count) return -1; consumed += length; r = ne_read_int(ctx->io, &timecode, 2); if (r != 1) return r; consumed += 2; r = ne_read_uint(ctx->io, &flags, 1); if (r != 1) return r; consumed += 1; frames = 0; /* flags are different between block and simpleblock, but lacing is encoded the same way */ lacing = (flags & BLOCK_FLAGS_LACING) >> 1; switch (lacing) { case LACING_NONE: frames = 1; break; case LACING_XIPH: case LACING_FIXED: case LACING_EBML: r = ne_read_uint(ctx->io, &frames, 1); if (r != 1) return r; consumed += 1; frames += 1; } if (frames > 256) return -1; switch (lacing) { case LACING_NONE: frame_sizes[0] = block_size - consumed; break; case LACING_XIPH: if (frames == 1) return -1; r = ne_read_xiph_lacing(ctx->io, block_size, &consumed, frames, frame_sizes); if (r != 1) return r; break; case LACING_FIXED: if ((block_size - consumed) % frames) return -1; for (i = 0; i < frames; ++i) frame_sizes[i] = (block_size - consumed) / frames; break; case LACING_EBML: if (frames == 1) return -1; r = ne_read_ebml_lacing(ctx->io, block_size, &consumed, frames, frame_sizes); if (r != 1) return r; break; } /* sanity check unlaced frame sizes against total block size. */ total = consumed; for (i = 0; i < frames; ++i) total += frame_sizes[i]; if (total > block_size) return -1; entry = ne_find_track_entry(ctx, (unsigned int)(track - 1)); if (!entry) return -1; track_scale = 1.0; tc_scale = ne_get_timecode_scale(ctx); assert(ctx->segment.cluster.tail->id == ID_CLUSTER); cluster = ctx->segment.cluster.tail->data; if (ne_get_uint(cluster->timecode, &cluster_tc) != 0) return -1; abs_timecode = timecode + cluster_tc; if (abs_timecode < 0) return -1; pkt = ne_alloc(sizeof(*pkt)); pkt->track = track - 1; pkt->timecode = (uint64_t)(abs_timecode * tc_scale * track_scale); ctx->log(ctx, NESTEGG_LOG_DEBUG, "%sblock t %lld pts %f f %llx frames: %llu", block_id == ID_BLOCK ? "" : "simple", pkt->track, pkt->timecode / 1e9, flags, frames); last = NULL; for (i = 0; i < frames; ++i) { if (frame_sizes[i] > LIMIT_FRAME) { nestegg_free_packet(pkt); return -1; } f = ne_alloc(sizeof(*f)); f->data = ne_alloc(frame_sizes[i]); f->length = frame_sizes[i]; r = ne_io_read(ctx->io, f->data, frame_sizes[i]); if (r != 1) { free(f->data); free(f); nestegg_free_packet(pkt); return -1; } if (!last) pkt->frame = f; else last->next = f; last = f; } *data = pkt; return 1; } static uint64_t ne_buf_read_id(unsigned char const * p, size_t length) { uint64_t id = 0; while (length--) { id <<= 8; id |= *p++; } return id; } static struct seek * ne_find_seek_for_id(struct ebml_list_node * seek_head, uint64_t id) { struct ebml_list * head; struct ebml_list_node * seek; struct ebml_binary binary_id; struct seek * s; while (seek_head) { assert(seek_head->id == ID_SEEK_HEAD); head = seek_head->data; seek = head->head; while (seek) { assert(seek->id == ID_SEEK); s = seek->data; if (ne_get_binary(s->id, &binary_id) == 0 && ne_buf_read_id(binary_id.data, binary_id.length) == id) return s; seek = seek->next; } seek_head = seek_head->next; } return NULL; } static struct cue_point * ne_find_cue_point_for_tstamp(struct ebml_list_node * cue_point, uint64_t scale, uint64_t tstamp) { uint64_t time; struct cue_point * c, * prev = NULL; while (cue_point) { assert(cue_point->id == ID_CUE_POINT); c = cue_point->data; if (!prev) prev = c; if (ne_get_uint(c->time, &time) == 0 && time * scale > tstamp) break; prev = cue_point->data; cue_point = cue_point->next; } return prev; } static int ne_is_suspend_element(uint64_t id) { /* this could search the tree of elements for DESC_FLAG_SUSPEND */ if (id == ID_SIMPLE_BLOCK || id == ID_BLOCK) return 1; return 0; } static void ne_null_log_callback(nestegg * ctx, unsigned int severity, char const * fmt, ...) { if (ctx && severity && fmt) return; } int nestegg_init(nestegg ** context, nestegg_io io, nestegg_log callback) { int r; uint64_t id, version, docversion; struct ebml_list_node * track; char * doctype; nestegg * ctx = NULL; if (!(io.read && io.seek && io.tell)) return -1; ctx = ne_alloc(sizeof(*ctx)); ctx->io = ne_alloc(sizeof(*ctx->io)); *ctx->io = io; ctx->log = callback; ctx->alloc_pool = ne_pool_init(); if (!ctx->log) ctx->log = ne_null_log_callback; r = ne_peek_element(ctx, &id, NULL); if (r != 1) { nestegg_destroy(ctx); return -1; } if (id != ID_EBML) { nestegg_destroy(ctx); return -1; } ctx->log(ctx, NESTEGG_LOG_DEBUG, "ctx %p", ctx); ne_ctx_push(ctx, ne_top_level_elements, ctx); r = ne_parse(ctx, NULL); if (r != 1) { nestegg_destroy(ctx); return -1; } if (ne_get_uint(ctx->ebml.ebml_read_version, &version) != 0) version = 1; if (version != 1) { nestegg_destroy(ctx); return -1; } if (ne_get_string(ctx->ebml.doctype, &doctype) != 0) doctype = "matroska"; if (strcmp(doctype, "webm") != 0) { nestegg_destroy(ctx); return -1; } if (ne_get_uint(ctx->ebml.doctype_read_version, &docversion) != 0) docversion = 1; if (docversion < 1 || docversion > 2) { nestegg_destroy(ctx); return -1; } if (!ctx->segment.tracks.track_entry.head) { nestegg_destroy(ctx); return -1; } track = ctx->segment.tracks.track_entry.head; ctx->track_count = 0; while (track) { ctx->track_count += 1; track = track->next; } *context = ctx; return 0; } void nestegg_destroy(nestegg * ctx) { while (ctx->ancestor) ne_ctx_pop(ctx); ne_pool_destroy(ctx->alloc_pool); free(ctx->io); free(ctx); } int nestegg_duration(nestegg * ctx, uint64_t * duration) { uint64_t tc_scale; double unscaled_duration; if (ne_get_float(ctx->segment.info.duration, &unscaled_duration) != 0) return -1; tc_scale = ne_get_timecode_scale(ctx); *duration = (uint64_t) (unscaled_duration * tc_scale); return 0; } int nestegg_tstamp_scale(nestegg * ctx, uint64_t * scale) { *scale = ne_get_timecode_scale(ctx); return 0; } int nestegg_track_count(nestegg * ctx, unsigned int * tracks) { *tracks = ctx->track_count; return 0; } int nestegg_track_seek(nestegg * ctx, unsigned int track, uint64_t tstamp) { int r; struct cue_point * cue_point; struct cue_track_positions * pos; struct saved_state state; struct seek * found; uint64_t seek_pos, tc_scale, t, id; struct ebml_list_node * node = ctx->segment.cues.cue_point.head; /* If there are no cues loaded, check for cues element in the seek head and load it. */ if (!node) { found = ne_find_seek_for_id(ctx->segment.seek_head.head, ID_CUES); if (!found) return -1; if (ne_get_uint(found->position, &seek_pos) != 0) return -1; /* Save old parser state. */ r = ne_ctx_save(ctx, &state); if (r != 0) return -1; /* Seek and set up parser state for segment-level element (Cues). */ r = ne_io_seek(ctx->io, ctx->segment_offset + seek_pos, NESTEGG_SEEK_SET); if (r != 0) return -1; ctx->last_id = 0; ctx->last_size = 0; r = ne_read_element(ctx, &id, NULL); if (r != 1) return -1; if (id != ID_CUES) return -1; ctx->ancestor = NULL; ne_ctx_push(ctx, ne_top_level_elements, ctx); ne_ctx_push(ctx, ne_segment_elements, &ctx->segment); ne_ctx_push(ctx, ne_cues_elements, &ctx->segment.cues); /* parser will run until end of cues element. */ ctx->log(ctx, NESTEGG_LOG_DEBUG, "seek: parsing cue elements"); r = ne_parse(ctx, ne_cues_elements); while (ctx->ancestor) ne_ctx_pop(ctx); /* Reset parser state to original state and seek back to old position. */ if (ne_ctx_restore(ctx, &state) != 0) return -1; if (r < 0) return -1; } tc_scale = ne_get_timecode_scale(ctx); cue_point = ne_find_cue_point_for_tstamp(ctx->segment.cues.cue_point.head, tc_scale, tstamp); if (!cue_point) return -1; node = cue_point->cue_track_positions.head; seek_pos = 0; while (node) { assert(node->id == ID_CUE_TRACK_POSITIONS); pos = node->data; if (ne_get_uint(pos->track, &t) == 0 && t - 1 == track) { if (ne_get_uint(pos->cluster_position, &seek_pos) != 0) return -1; break; } node = node->next; } /* Seek and set up parser state for segment-level element (Cluster). */ r = ne_io_seek(ctx->io, ctx->segment_offset + seek_pos, NESTEGG_SEEK_SET); if (r != 0) return -1; ctx->last_id = 0; ctx->last_size = 0; while (ctx->ancestor) ne_ctx_pop(ctx); ne_ctx_push(ctx, ne_top_level_elements, ctx); ne_ctx_push(ctx, ne_segment_elements, &ctx->segment); ctx->log(ctx, NESTEGG_LOG_DEBUG, "seek: parsing cluster elements"); r = ne_parse(ctx, NULL); if (r != 1) return -1; if (!ne_is_suspend_element(ctx->last_id)) return -1; return 0; } int nestegg_track_type(nestegg * ctx, unsigned int track) { struct track_entry * entry; uint64_t type; entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (ne_get_uint(entry->type, &type) != 0) return -1; if (type & TRACK_TYPE_VIDEO) return NESTEGG_TRACK_VIDEO; if (type & TRACK_TYPE_AUDIO) return NESTEGG_TRACK_AUDIO; return -1; } int nestegg_track_codec_id(nestegg * ctx, unsigned int track) { char * codec_id; struct track_entry * entry; entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (ne_get_string(entry->codec_id, &codec_id) != 0) return -1; if (strcmp(codec_id, TRACK_ID_VP8) == 0) return NESTEGG_CODEC_VP8; if (strcmp(codec_id, TRACK_ID_VP9) == 0) return NESTEGG_CODEC_VP9; if (strcmp(codec_id, TRACK_ID_VORBIS) == 0) return NESTEGG_CODEC_VORBIS; return -1; } int nestegg_track_codec_data_count(nestegg * ctx, unsigned int track, unsigned int * count) { struct track_entry * entry; struct ebml_binary codec_private; unsigned char * p; *count = 0; entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (nestegg_track_codec_id(ctx, track) != NESTEGG_CODEC_VORBIS) return -1; if (ne_get_binary(entry->codec_private, &codec_private) != 0) return -1; if (codec_private.length < 1) return -1; p = codec_private.data; *count = *p + 1; if (*count > 3) return -1; return 0; } int nestegg_track_codec_data(nestegg * ctx, unsigned int track, unsigned int item, unsigned char ** data, size_t * length) { struct track_entry * entry; struct ebml_binary codec_private; uint64_t sizes[3], total; unsigned char * p; unsigned int count, i; *data = NULL; *length = 0; entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (nestegg_track_codec_id(ctx, track) != NESTEGG_CODEC_VORBIS) return -1; if (ne_get_binary(entry->codec_private, &codec_private) != 0) return -1; p = codec_private.data; count = *p++ + 1; if (count > 3) return -1; i = 0; total = 0; while (--count) { sizes[i] = ne_xiph_lace_value(&p); total += sizes[i]; i += 1; } sizes[i] = codec_private.length - total - (p - codec_private.data); for (i = 0; i < item; ++i) { if (sizes[i] > LIMIT_FRAME) return -1; p += sizes[i]; } *data = p; *length = sizes[item]; return 0; } int nestegg_track_video_params(nestegg * ctx, unsigned int track, nestegg_video_params * params) { struct track_entry * entry; uint64_t value; memset(params, 0, sizeof(*params)); entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (nestegg_track_type(ctx, track) != NESTEGG_TRACK_VIDEO) return -1; if (ne_get_uint(entry->video.pixel_width, &value) != 0) return -1; params->width = (unsigned int)value; if (ne_get_uint(entry->video.pixel_height, &value) != 0) return -1; params->height = (unsigned int)value; value = 0; ne_get_uint(entry->video.pixel_crop_bottom, &value); params->crop_bottom = (unsigned int)value; value = 0; ne_get_uint(entry->video.pixel_crop_top, &value); params->crop_top = (unsigned int)value; value = 0; ne_get_uint(entry->video.pixel_crop_left, &value); params->crop_left = (unsigned int)value; value = 0; ne_get_uint(entry->video.pixel_crop_right, &value); params->crop_right = (unsigned int)value; value = params->width; ne_get_uint(entry->video.display_width, &value); params->display_width = (unsigned int)value; value = params->height; ne_get_uint(entry->video.display_height, &value); params->display_height = (unsigned int)value; return 0; } int nestegg_track_audio_params(nestegg * ctx, unsigned int track, nestegg_audio_params * params) { struct track_entry * entry; uint64_t value; memset(params, 0, sizeof(*params)); entry = ne_find_track_entry(ctx, track); if (!entry) return -1; if (nestegg_track_type(ctx, track) != NESTEGG_TRACK_AUDIO) return -1; params->rate = 8000; ne_get_float(entry->audio.sampling_frequency, ¶ms->rate); value = 1; ne_get_uint(entry->audio.channels, &value); params->channels = (unsigned int)value; value = 16; ne_get_uint(entry->audio.bit_depth, &value); params->depth = (unsigned int)value; return 0; } int nestegg_read_packet(nestegg * ctx, nestegg_packet ** pkt) { int r; uint64_t id, size; *pkt = NULL; for (;;) { r = ne_peek_element(ctx, &id, &size); if (r != 1) return r; /* any suspend fields must be handled here */ if (ne_is_suspend_element(id)) { r = ne_read_element(ctx, &id, &size); if (r != 1) return r; /* the only suspend fields are blocks and simple blocks, which we handle directly. */ r = ne_read_block(ctx, id, size, pkt); return r; } r = ne_parse(ctx, NULL); if (r != 1) return r; } return 1; } void nestegg_free_packet(nestegg_packet * pkt) { struct frame * frame; while (pkt->frame) { frame = pkt->frame; pkt->frame = frame->next; free(frame->data); free(frame); } free(pkt); } int nestegg_packet_track(nestegg_packet * pkt, unsigned int * track) { *track = (unsigned int)pkt->track; return 0; } int nestegg_packet_tstamp(nestegg_packet * pkt, uint64_t * tstamp) { *tstamp = pkt->timecode; return 0; } int nestegg_packet_count(nestegg_packet * pkt, unsigned int * count) { struct frame * f = pkt->frame; *count = 0; while (f) { *count += 1; f = f->next; } return 0; } int nestegg_packet_data(nestegg_packet * pkt, unsigned int item, unsigned char ** data, size_t * length) { struct frame * f = pkt->frame; unsigned int count = 0; *data = NULL; *length = 0; while (f) { if (count == item) { *data = f->data; *length = f->length; return 0; } count += 1; f = f->next; } return -1; }