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/*
Copyright Jeroen Vreeken (jeroen@vreeken.net), 2018
This program 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 3 of the License, or
(at your option) any later version.
This program 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, see <http://www.gnu.org/licenses/>.
*/
//#define TESTMAIN
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <stdbool.h>
#include "isom.h"
struct fileparse {
uint8_t *box;
size_t cur_size;
size_t box_size;
ssize_t (*data_cb)(void *data, size_t size);
int (*trigger_cb)(enum fileparse_trigger trig);
};
char *subbox[] = {
"moov",
"trak",
"mdia",
"minf",
"stbl",
"moof",
"traf",
};
char *removebox[] = {
"tfdt",
};
char *dumpbox[] = {
"mvhd",
"mfhd",
"stts",
"tfdt",
// "trun",
};
void printbox(void *box, size_t *box_size, int level)
{
uint8_t *cbox = box;
uint8_t *type = &cbox[4];
char levelstr[level*2+1];
memset(levelstr, ' ', level*2);
levelstr[level*2] = 0;
printf("%sbox: %c%c%c%c %zd\n", levelstr,
type[0], type[1], type[2], type[3], *box_size);
int i;
bool has_subbox = false;
for (i = 0; i < sizeof(subbox)/sizeof(subbox[0]); i++) {
if (!memcmp(subbox[i], type, 4)) {
has_subbox = true;
}
}
bool is_removebox = false;
for (i = 0; i < sizeof(removebox)/sizeof(removebox[0]); i++) {
if (!memcmp(removebox[i], type, 4)) {
is_removebox = true;
}
}
bool is_dumpbox = false;
for (i = 0; i < sizeof(dumpbox)/sizeof(dumpbox[0]); i++) {
if (!memcmp(dumpbox[i], type, 4)) {
is_dumpbox = true;
}
}
if (is_dumpbox) {
printf("%s ", levelstr);
for (i = 0; i < *box_size; i++) {
if (i == 8)
printf(" ");
printf("%02x", cbox[i]);
}
printf("\n");
}
if (is_removebox) {
*box_size = 0;
return;
}
size_t pos;
if (has_subbox) for (pos = 8; pos < *box_size; ) {
size_t subbox_size =
(cbox[pos + 0] << 24) |
(cbox[pos + 1] << 16) |
(cbox[pos + 2] << 8) |
(cbox[pos + 3] << 0);
size_t org_size = subbox_size;
printbox(&cbox[pos], &subbox_size, level+1);
if (subbox_size < org_size) {
size_t removed = org_size - subbox_size;
memmove(&cbox[pos+subbox_size], &cbox[pos+removed], *box_size - (pos + removed));
printf("%sremoved %zd, %zd <- %zd (%zd) %zd\n", levelstr, removed, pos, pos+removed, *box_size - (pos+removed), subbox_size);
*box_size -= removed;
}
pos += subbox_size;
}
printf("%s%zd\n", levelstr, *box_size);
cbox[0] = (*box_size >> 24) & 0xff;
cbox[1] = (*box_size >> 16) & 0xff;
cbox[2] = (*box_size >> 8) & 0xff;
cbox[3] = (*box_size >> 0) & 0xff;
}
int isom_parse(struct fileparse *isom, void *buffer, size_t size)
{
char *cbuffer = buffer;
while (size) {
if (isom->cur_size < 4) {
size_t copy = 4 - isom->cur_size;
if (size < copy) {
copy = size;
}
memcpy(&isom->box[isom->cur_size], cbuffer, copy);
cbuffer += copy;
size -= copy;
isom->cur_size += copy;
if (isom->cur_size == 4) {
isom->box_size =
(isom->box[0] << 24) |
(isom->box[1] << 16) |
(isom->box[2] << 8) |
(isom->box[3] << 0);
isom->box = realloc(isom->box, isom->box_size);
}
} else {
size_t copy = isom->box_size - isom->cur_size;
if (size < copy) {
copy = size;
}
memcpy(&isom->box[isom->cur_size], cbuffer, copy);
cbuffer += copy;
size -= copy;
isom->cur_size += copy;
}
if (isom->cur_size == isom->box_size) {
printbox(isom->box, &isom->box_size, 0);
write(2, isom->box, isom->box_size);
isom->cur_size = 0;
}
}
return 0;
}
struct fileparse *isom_create(
ssize_t (*data_cb)(void *data, size_t size),
int (*trigger_cb)(enum fileparse_trigger trig),
int (**parse)(struct fileparse *mat, void *buffer, size_t size))
{
struct fileparse *isom;
isom = calloc(sizeof(struct fileparse), 1);
if (!isom)
goto err;
isom->box = malloc(4);
*parse = isom_parse;
isom->data_cb = data_cb;
isom->trigger_cb = trigger_cb;
err:
return isom;
}
#ifdef TESTMAIN
static ssize_t data_cb(void *data, size_t size)
{
printf("data: %zd\n", size);
return size;
}
static int trigger_cb(enum fileparse_trigger trig)
{
printf("Trigger: %d\n", trig);
return 0;
}
int main(int argc, char **argv)
{
char buffer[1000];
ssize_t r;
int (*parse)(struct fileparse *mat, void *buffer, size_t size);
struct fileparse *isom = isom_create(data_cb, trigger_cb, &parse);
do {
r = read(0, buffer, 1000);
if (r > 0) {
isom_parse(isom, buffer, r);
}
} while (r > 0);
return 0;
}
#endif