path: root/vobsub.c

/*
 * Some code freely inspired from VobSub <URL:http://vobsub.edensrising.com>,
 * with kind permission from Gabest <gabest@freemail.hu>
 */
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>

#include "config.h"
#include "version.h"

#include "vobsub.h"
#include "spudec.h"
#include "mp_msg.h"
#ifdef USE_UNRAR_EXEC
#include "unrar_exec.h"
#endif
#include "libavutil/common.h"

extern int vobsub_id;
// Record the original -vobsubid set by commandline, since vobsub_id will be
// overridden if slang match any of vobsub streams.
static int vobsubid = -2;

/**********************************************************************
 * RAR stream handling
 * The RAR file must have the same basename as the file to open
 **********************************************************************/
#ifdef USE_UNRAR_EXEC
typedef struct {
    FILE *file;
    unsigned char *data;
    unsigned long size;
    unsigned long pos;
} rar_stream_t;
static rar_stream_t *
rar_open(const char *const filename, const char *const mode)
{
    rar_stream_t *stream;
    /* unrar_exec can only read */
    if (strcmp("r", mode) && strcmp("rb", mode)) {
	errno = EINVAL;
	return NULL;
    }
    stream = malloc(sizeof(rar_stream_t));
    if (stream == NULL)
	return NULL;
    /* first try normal access */
    stream->file = fopen(filename, mode);
    if (stream->file == NULL) {
	char *rar_filename;
	const char *p;
	int rc;
	/* Guess the RAR archive filename */
	rar_filename = NULL;
	p = strrchr(filename, '.');
	if (p) {
	    ptrdiff_t l = p - filename;
	    rar_filename = malloc(l + 5);
	    if (rar_filename == NULL) {
		free(stream);
		return NULL;
	    }
	    strncpy(rar_filename, filename, l);
	    strcpy(rar_filename + l, ".rar");
	}
	else {
	    rar_filename = malloc(strlen(filename) + 5);
	    if (rar_filename == NULL) {
		free(stream);
		return NULL;
	    }
	    strcpy(rar_filename, filename);
	    strcat(rar_filename, ".rar");
	}
	/* get rid of the path if there is any */
	if ((p = strrchr(filename, '/')) == NULL) {
		p = filename;
	} else {
		p++;
	}
	rc = unrar_exec_get(&stream->data, &stream->size, p, rar_filename);
	if (!rc) {
	    /* There is no matching filename in the archive. However, sometimes
	     * the files we are looking for have been given arbitrary names in the archive.
	     * Let's look for a file with an exact match in the extension only. */
	    int i, num_files, name_len;
	    ArchiveList_struct *list, *lp;
	    num_files = unrar_exec_list(rar_filename, &list);
	    if (num_files > 0) {
		char *demanded_ext;
		demanded_ext = strrchr (p, '.');
		if (demanded_ext) {
		    int demanded_ext_len = strlen (demanded_ext);
	    	    for (i=0, lp=list; i<num_files; i++, lp=lp->next) {
			name_len = strlen (lp->item.Name);
			if (name_len >= demanded_ext_len && !strcasecmp (lp->item.Name + name_len - demanded_ext_len, demanded_ext)) {
	                    rc = unrar_exec_get(&stream->data, &stream->size,
                                                lp->item.Name, rar_filename);
		            if (rc) break;
			}
		    }
		}
	    	unrar_exec_freelist(list);
	    }
	    if (!rc) {
		free(rar_filename);
		free(stream);
		return NULL;
	    }
	}

	free(rar_filename);
	stream->pos = 0;
    }
    return stream;
}

static int
rar_close(rar_stream_t *stream)
{
    if (stream->file)
	return fclose(stream->file);
    free(stream->data);
    return 0;
}

static int
rar_eof(rar_stream_t *stream)
{
    if (stream->file)
	return feof(stream->file);
    return stream->pos >= stream->size;
}

static long
rar_tell(rar_stream_t *stream)
{
    if (stream->file)
	return ftell(stream->file);
    return stream->pos;
}

static int
rar_seek(rar_stream_t *stream, long offset, int whence)
{
    if (stream->file)
	return fseek(stream->file, offset, whence);
    switch (whence) {
    case SEEK_SET:
	if (offset < 0) {
	    errno = EINVAL;
	    return -1;
	}
	stream->pos = offset;
	break;
    case SEEK_CUR:
	if (offset < 0 && stream->pos < (unsigned long) -offset) {
	    errno = EINVAL;
	    return -1;
	}
	stream->pos += offset;
	break;
    case SEEK_END:
	if (offset < 0 && stream->size < (unsigned long) -offset) {
	    errno = EINVAL;
	    return -1;
	}
	stream->pos = stream->size + offset;
	break;
    default:
	errno = EINVAL;
	return -1;
    }
    return 0;
}

static int
rar_getc(rar_stream_t *stream)
{
    if (stream->file)
	return getc(stream->file);
    if (rar_eof(stream))
	return EOF;
    return stream->data[stream->pos++];
}

static size_t
rar_read(void *ptr, size_t size, size_t nmemb, rar_stream_t *stream)
{
    size_t res;
    unsigned long remain;
    if (stream->file)
	return fread(ptr, size, nmemb, stream->file);
    if (rar_e