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/*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
*
* EBML parser
* a lot of ideas from the gstreamer parser
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#define LOG_MODULE "ebml"
#define LOG_VERBOSE
/*
#define LOG
*/
#include <xine/xine_internal.h>
#include <xine/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 = xine_xmalloc(sizeof(ebml_parser_t));
ebml->xine = xine;
ebml->input = input;
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: %" PRIdMAX ", %" PRIu64 "; elem: %" PRIdMAX ", %" PRIu64 "\n",
(intmax_t)parent_elem->start, parent_elem->len, (intmax_t)elem->start, elem->len);
ebml->level--;
if (ebml->level == 0) break;
parent_elem = &ebml->elem_stack[ebml->level - 1];
}
}
lprintf("id: 0x%x, len: %" PRIu64 ", 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 %" PRIdMAX "\n",
data[0], (intmax_t)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 %" PRIdMAX "\n", (intmax_t)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 %" PRIdMAX "\n", (intmax_t)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 %" PRIdMAX "\n",
data[0], (intmax_t)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 %" PRIdMAX "\n", (intmax_t)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, void *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 %" PRIdMAX "\n", (intmax_t)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 %" PRIu64 "\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;
}
#if 0
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 %" PRIu64 "\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;
}
#endif
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 %" PRIu64 "\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) = _X_BE_32(data);
*num = f;
} else {
double d;
*((uint64_t *) &d) = _X_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;
}
#if 0
int ebml_read_utf8 (ebml_parser_t *ebml, ebml_elem_t *elem, char *str) {
return ebml_read_ascii (ebml, elem, str);
}
#endif
char *ebml_alloc_read_ascii (ebml_parser_t *ebml, ebml_elem_t *elem)
{
char *text;
if (elem->len >= 4096)
return NULL;
text = malloc(elem->len + 1);
if (text)
{
text[elem->len] = '\0';
if (ebml_read_ascii (ebml, elem, text))
return text;
free (text);
}
return NULL;
}
#if 0
int ebml_read_date (ebml_parser_t *ebml, ebml_elem_t *elem, int64_t *date) {
return ebml_read_sint (ebml, elem, date);
}
#endif
int ebml_read_master (ebml_parser_t *ebml, ebml_elem_t *elem) {
ebml_elem_t *top_elem;
if (ebml->level < 0) {
xprintf(ebml->xine, XINE_VERBOSITY_LOG,
"ebml: invalid current level\n");
return 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: %" PRIu64 ", 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;
}
int ebml_read_binary(ebml_parser_t *ebml, ebml_elem_t *elem, void *binary) {
return !!ebml_read_elem_data(ebml, binary, elem->len);
}
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: %" PRIu64 "\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: %" PRIu64 "\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: %" PRIu64 "\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: %" PRIu64 "\n", num);
ebml->max_size_len = num;
break;
}
case EBML_ID_DOCTYPE: {
char *text = ebml_alloc_read_ascii (ebml, &elem);
if (!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: %" PRIu64 "\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: %" PRIu64 "\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;
}