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-rw-r--r--src/demuxers/ebml.c468
1 files changed, 468 insertions, 0 deletions
diff --git a/src/demuxers/ebml.c b/src/demuxers/ebml.c
new file mode 100644
index 000000000..b6f0658fc
--- /dev/null
+++ b/src/demuxers/ebml.c
@@ -0,0 +1,468 @@
+/*
+ * Copyright (C) 2000-2003 the xine project
+ *
+ * This file is part of xine, a free video player.
+ *
+ * xine is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * xine 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ *
+ * EBML parser
+ * a lot of ideas from the gstreamer parser
+ *
+ * $Id: ebml.c,v 1.1 2004/01/05 00:40:54 tmattern Exp $
+ *
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+
+#define LOG_MODULE "ebml"
+#define LOG_VERBOSE
+/*
+#define LOG
+*/
+#include "xine_internal.h"
+#include "xineutils.h"
+#include "bswap.h"
+
+#include "ebml.h"
+
+
+ebml_parser_t *new_ebml_parser (xine_t *xine, input_plugin_t *input) {
+ ebml_parser_t *ebml;
+
+ ebml = malloc(sizeof(ebml_parser_t));
+ ebml->xine = xine;
+ ebml->input = input;
+
+ ebml->version = 0;
+ ebml->read_version = 0;
+ ebml->max_id_len = 0;
+ ebml->max_size_len = 0;
+ ebml->doctype = NULL;
+ ebml->doctype_version = 0;
+ ebml->doctype_read_version = 0;
+
+ ebml->level = 0;
+
+ return ebml;
+}
+
+
+void dispose_ebml_parser(ebml_parser_t *ebml) {
+ free(ebml);
+}
+
+
+uint32_t ebml_get_next_level(ebml_parser_t *ebml, ebml_elem_t *elem) {
+ ebml_elem_t *parent_elem;
+
+ if (ebml->level > 0) {
+ parent_elem = &ebml->elem_stack[ebml->level - 1];
+ while ((elem->start + elem->len) >= (parent_elem->start + parent_elem->len)) {
+ lprintf("parent: %lld, %lld; elem: %lld, %lld\n",
+ parent_elem->start, parent_elem->len, elem->start, elem->len);
+ ebml->level--;
+ if (ebml->level == 0) break;
+ parent_elem = &ebml->elem_stack[ebml->level - 1];
+ }
+ }
+ lprintf("id: 0x%x, len: %lld, next_level: %d\n", elem->id, elem->len, ebml->level);
+ return ebml->level;
+}
+
+
+static int ebml_read_elem_id(ebml_parser_t *ebml, uint32_t *id) {
+ uint8_t data[4];
+ uint32_t mask = 0x80;
+ uint32_t value;
+ int size = 1;
+ int i;
+
+ if (ebml->input->read(ebml->input, data, 1) != 1) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: read error\n");
+ return 0;
+ }
+ value = data[0];
+
+ /* compute the size of the ID (1-4 bytes)*/
+ while (size <= 4 && !(value & mask)) {
+ size++;
+ mask >>= 1;
+ }
+ if (size > 4) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: invalid EBML ID size (0x%x) at position %llu\n", data[0], pos);
+ return 0;
+ }
+
+ /* read the rest of the id */
+ if (ebml->input->read(ebml->input, data + 1, size - 1) != (size - 1)) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: read error at position %llu\n", pos);
+ return 0;
+ }
+ for(i = 1; i < size; i++) {
+ value = (value << 8) | data[i];
+ }
+ *id = value;
+
+ return 1;
+}
+
+
+static int ebml_read_elem_len(ebml_parser_t *ebml, uint64_t *len) {
+ uint8_t data[8];
+ uint32_t mask = 0x80;
+ int size = 1;
+ int ff_bytes;
+ uint64_t value;
+ int i;
+
+ if (ebml->input->read(ebml->input, data, 1) != 1) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: read error at position %llu\n", pos);
+ return 0;
+ }
+ value = data[0];
+
+ /* compute the size of the "data len" (1-8 bytes) */
+ while (size <= 8 && !(value & mask)) {
+ size++;
+ mask >>= 1;
+ }
+ if (size > 8) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: Invalid EBML length size (0x%x) at position %llu\n", data[0], pos);
+ return 0;
+ }
+
+ /* remove size bits */
+ value &= mask - 1;
+
+ /* check if the first byte is full */
+ if (value == (mask - 1))
+ ff_bytes = 1;
+ else
+ ff_bytes = 0;
+
+ /* read the rest of the len */
+ if (ebml->input->read(ebml->input, data + 1, size - 1) != (size - 1)) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: read error at position %llu\n", pos);
+ return 0;
+ }
+ for (i = 1; i < size; i++) {
+ if (data[i] == 0xff)
+ ff_bytes++;
+ value = (value << 8) | data[i];
+ }
+
+ if (ff_bytes == size)
+ *len = -1;
+ else
+ *len = value;
+
+ return 1;
+}
+
+
+static int ebml_read_elem_data(ebml_parser_t *ebml, int8_t *buf, int64_t len) {
+
+ if (ebml->input->read(ebml->input, buf, len) != len) {
+ off_t pos = ebml->input->get_current_pos(ebml->input);
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: read error at position %llu\n", pos);
+ return 0;
+ }
+
+ return 1;
+}
+
+
+int ebml_skip(ebml_parser_t *ebml, ebml_elem_t *elem) {
+ if (ebml->input->seek(ebml->input, elem->len, SEEK_CUR) < 0) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: seek error\n");
+ return 0;
+ }
+
+ return 1;
+}
+
+
+int ebml_read_elem_head(ebml_parser_t *ebml, ebml_elem_t *elem) {
+
+ if (!ebml_read_elem_id(ebml, &elem->id))
+ return 0;
+
+ if (!ebml_read_elem_len(ebml, &elem->len))
+ return 0;
+
+ elem->start = ebml->input->get_current_pos(ebml->input);
+ return 1;
+}
+
+
+int ebml_read_uint(ebml_parser_t *ebml, ebml_elem_t *elem, uint64_t *num) {
+ uint8_t data[8];
+ uint64_t size = elem->len;
+
+ if ((elem->len < 1) || (elem->len > 8)) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: Invalid integer element size %lld\n", size);
+ return 0;
+ }
+
+ if (!ebml_read_elem_data (ebml, data, size))
+ return 0;
+
+ *num = 0;
+ while (size > 0) {
+ *num = (*num << 8) | data[elem->len - size];
+ size--;
+ }
+
+ return 1;
+}
+
+int ebml_read_sint (ebml_parser_t *ebml, ebml_elem_t *elem, int64_t *num) {
+ uint8_t data[8];
+ uint64_t size = elem->len;
+
+ if ((elem->len < 1) || (elem->len > 8)) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: Invalid integer element size %lld\n", size);
+ return 0;
+ }
+
+ if (!ebml_read_elem_data(ebml, data, size))
+ return 0;
+
+ /* propagate negative bit */
+ if (data[0] & 80)
+ *num = -1;
+ else
+ *num = 0;
+
+ while (size > 0) {
+ *num = (*num << 8) | data[elem->len - size];
+ size--;
+ }
+
+ return 1;
+}
+
+
+int ebml_read_float (ebml_parser_t *ebml, ebml_elem_t *elem, double *num) {
+ uint8_t data[10];
+ uint64_t size = elem->len;
+
+ if ((size != 4) && (size != 8) && (size != 10)) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: Invalid float element size %lld\n", size);
+ return 0;
+ }
+
+ if (!ebml_read_elem_data(ebml, data, size))
+ return 0;
+
+ if (size == 10) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: FIXME! 10-byte floats unimplemented\n");
+ return 0;
+ }
+
+ if (size == 4) {
+ float f;
+
+ *((uint32_t *) &f) = BE_32(data);
+ *num = f;
+ } else {
+ double d;
+
+ *((uint64_t *) &d) = BE_64(data);
+ *num = d;
+ }
+ return 1;
+}
+
+int ebml_read_ascii(ebml_parser_t *ebml, ebml_elem_t *elem, char *str) {
+ uint64_t size = elem->len;
+
+ if (!ebml_read_elem_data(ebml, str, size))
+ return 0;
+
+ return 1;
+}
+
+int ebml_read_utf8 (ebml_parser_t *ebml, ebml_elem_t *elem, char *str) {
+ return ebml_read_ascii (ebml, elem, str);
+}
+
+int ebml_read_date (ebml_parser_t *ebml, ebml_elem_t *elem, int64_t *date) {
+ return ebml_read_sint (ebml, elem, date);
+}
+
+int ebml_read_master (ebml_parser_t *ebml, ebml_elem_t *elem) {
+ ebml_elem_t *top_elem;
+
+ if (ebml->level >= 0) {
+ top_elem = &ebml->elem_stack[ebml->level];
+ top_elem->start = elem->start;
+ top_elem->len = elem->len;
+ top_elem->id = elem->id;
+
+ ebml->level++;
+ lprintf("id: 0x%x, len: %lld, level: %d\n", elem->id, elem->len, ebml->level);
+ if (ebml->level >= EBML_STACK_SIZE) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: max level exceeded\n");
+ return 0;
+ }
+ return 1;
+ } else {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: invalid current level\n");
+ return 0;
+ }
+}
+
+int ebml_read_binary(ebml_parser_t *ebml, ebml_elem_t *elem, uint8_t *binary) {
+ if (!ebml_read_elem_data(ebml, binary, elem->len))
+ return 0;
+
+ return 1;
+}
+
+int ebml_check_header(ebml_parser_t *ebml) {
+ uint32_t next_level;
+ ebml_elem_t master;
+
+ if (!ebml_read_elem_head(ebml, &master)) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: invalid master element\n");
+ return 0;
+ }
+
+ if (master.id != EBML_ID_EBML) {
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: invalid master element\n");
+ return 0;
+ }
+
+ if (!ebml_read_master (ebml, &master))
+ return 0;
+
+ next_level = 1;
+ while (next_level == 1) {
+ ebml_elem_t elem;
+
+ if (!ebml_read_elem_head(ebml, &elem))
+ return 0;
+
+ switch (elem.id) {
+ case EBML_ID_EBMLVERSION: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("ebml_version: %lld\n", num);
+ ebml->version = num;
+ break;
+ }
+
+ case EBML_ID_EBMLREADVERSION: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("ebml_read_version: %lld\n", num);
+ if (num != EBML_VERSION)
+ return 0;
+ ebml->read_version = num;
+ break;
+ }
+
+ case EBML_ID_EBMLMAXIDLENGTH: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("ebml_max_id_length: %lld\n", num);
+ ebml->max_id_len = num;
+ break;
+ }
+
+ case EBML_ID_EBMLMAXSIZELENGTH: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("ebml_max_size_length: %lld\n", num);
+ ebml->max_size_len = num;
+ break;
+ }
+
+ case EBML_ID_DOCTYPE: {
+ char *text = malloc(elem.len + 1);
+
+ text[elem.len] = '\0';
+ if (!ebml_read_ascii (ebml, &elem, text))
+ return 0;
+
+ lprintf("doctype: %s\n", text);
+ if (ebml->doctype)
+ free (ebml->doctype);
+ ebml->doctype = text;
+ break;
+ }
+
+ case EBML_ID_DOCTYPEVERSION: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("doctype_version: %lld\n", num);
+ ebml->doctype_version = num;
+ break;
+ }
+
+ case EBML_ID_DOCTYPEREADVERSION: {
+ uint64_t num;
+
+ if (!ebml_read_uint (ebml, &elem, &num))
+ return 0;
+ lprintf("doctype_read_version: %lld\n", num);
+ ebml->doctype_read_version = num;
+ break;
+ }
+
+ default:
+ xprintf(ebml->xine, XINE_VERBOSITY_LOG,
+ "ebml: Unknown data type 0x%x in EBML header (ignored)\n", elem.id);
+ }
+ next_level = ebml_get_next_level(ebml, &elem);
+ }
+
+ return 1;
+}
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