EMILE/libstream/stream_open.c

/*
 *
 * (c) 2005 Laurent Vivier <Laurent@lvivier.info>
 *
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "libstream.h"
#ifdef FLOPPY_SUPPORT
#include <libfloppy.h>
#endif
#ifdef SCSI_SUPPORT
#include <libscsi.h>
#endif
#ifdef BLOCK_SUPPORT
#include <libblock.h>
#endif
#ifdef CONTAINER_SUPPORT
#include <libcontainer.h>
#endif
#ifdef ISO9660_SUPPORT
#include <libiso9660.h>
#endif
#ifdef EXT2_SUPPORT
#include <libext2.h>
#endif
#ifdef MAP_SUPPORT
#include <libmap.h>
#endif

extern int default_unit;

static char* get_fs(char *path, fs_t *fs)
{
#ifdef BLOCK_SUPPORT
	if (strncmp("block:", path, 6) == 0)
	{
		*fs = fs_BLOCK;
		return path + 6;
	}
#endif
#ifdef CONTAINER_SUPPORT
	if (strncmp("container:", path, 10) == 0)
	{
		*fs = fs_CONTAINER;
		return path + 10;
	}
#endif
#ifdef ISO9660_SUPPORT
	if (strncmp("iso9660:", path, 8) == 0)
	{
		*fs = fs_ISO9660;
		return path + 8;
	}
#endif
#ifdef EXT2_SUPPORT
	if (strncmp("ext2:", path, 5) == 0)
	{
		*fs = fs_EXT2;
		return path + 5;
	}
#endif
	*fs = fs_NONE;
	return path;
}

static char *get_device(char* path, 
		device_t *device, int *unit, int* partition)
{
	if (*path == '(') {
		int nb;

		path++;

#ifdef FLOPPY_SUPPORT
		if (strncmp("fd", path, 2) == 0) {
			*device = device_FLOPPY;
			path += 2;
		} else
#endif
#ifdef SCSI_SUPPORT
		if (strncmp("sd", path, 2) == 0) {
			*device = device_SCSI;
			path += 2;
		} else
#endif
			return NULL;

		nb = 0;
		while ( (*path >= '0') && (*path <= '9') ) {
			nb = (nb * 10) + (*path - '0');
			path++;
		}
		*unit = nb;

		*partition = -1;
		if ( (*path == 0) || (*path == ')') )
		{
			path++;
			return path;
		}

		if (*path != ',')
			return NULL;
		path++;

		nb = 0;
		while ( (*path >= '0') && (*path <= '9') ) {
			nb = (nb * 10) + (*path - '0');
			path++;
		}
		*partition = nb;
		if ( (*path == 0) || (*path == ')') )
		{
			path++;
			return path;
		}
	} else if (default_unit != -1) {
		*device = device_SCSI;
		*unit = default_unit;
		*partition = -1;
		return path;
	}

	return NULL;
}

stream_t *stream_open(char *dev)
{
	stream_t *stream;
	fs_t fs;
	device_t device;
	int unit, partition;
	char *current;
	int ret;

	current = get_fs(dev, &fs);

	current = get_device(current, &device, &unit, &partition);
	if (current == NULL)
	{
		printf("Cannot identify given device\n");
		return NULL;
	}
	stream = (stream_t*)malloc(sizeof(stream_t));

	stream->fs_id = fs,
	stream->device_id = device;
	stream->unit = unit;
	stream->partition = partition;

	switch(device)
	{
#ifdef FLOPPY_SUPPORT
		case device_FLOPPY:
			if (partition != -1)
			{
				free(stream);
				return NULL;
			}
			stream->device.data = floppy_open(unit);
			if (stream->device.data == NULL)
			{
				free(stream);
				return NULL;
			}
			stream->device.read_sector = 
				(stream_read_sector_t)floppy_read_sector;
			stream->device.close = (stream_close_t)floppy_close;
			stream->device.get_blocksize = 
				(stream_get_blocksize_t)floppy_get_blocksize; 
			break;
#endif /* FLOPPY_SUPPORT */

#ifdef SCSI_SUPPORT
		case device_SCSI:
			stream->device.data = scsi_open(unit);
			if (stream->device.data == NULL)
			{
				free(stream);
				return NULL;
			}
			stream->device.read_sector = 
				(stream_read_sector_t)scsi_read_sector;
			stream->device.close = (stream_close_t)scsi_close; 
			stream->device.get_blocksize = 
				(stream_get_blocksize_t)scsi_get_blocksize; 
			break;
#endif /* SCSI_SUPPORT */

		default:
			free(stream);
			return NULL;
			break;
	}
	if (partition != -1)
	{
#ifdef MAP_SUPPORT
		if (map_init(&stream->device, partition) == -1)
		{
		        printf("Cannot open map\n");
			stream->device.close(stream->volume);
			free(stream);
			return NULL;
		}
#else
		stream->device.close(stream->device.data);
		free(stream);
		return NULL;
#endif /* MAP_SUPPORT */
	}

	switch(fs)
	{
#ifdef EXT2_SUPPORT
	case fs_EXT2:
		ret = ext2_init(&stream->device, &stream->fs);
		break;
#endif
#ifdef ISO9660_SUPPORT
	case fs_ISO9660:
		ret = iso9660_init(&stream->device, &stream->fs);
		break;
#endif
#ifdef CONTAINER_SUPPORT
	case fs_CONTAINER:
		ret = container_init(&stream->device, &stream->fs);
		break;
#endif
#ifdef BLOCK_SUPPORT
	case fs_BLOCK:
		ret = block_init(&stream->device, &stream->fs);
		break;
#endif
	case fs_NONE:
		ret = -1;
#ifdef EXT2_SUPPORT
		ret = ext2_init(&stream->device, &stream->fs);
#endif
#ifdef ISO9660_SUPPORT
		if (ret == -1)
			ret = iso9660_init(&stream->device, &stream->fs);
#endif
		break;
	default:
		ret = -1;
		break;
	}
	if (ret == -1)
	{
		stream->device.close(stream->device.data);
		free(stream);
		return NULL;
	}
	stream->volume = stream->fs.mount(&stream->device);
	if (stream->volume == NULL) {
		stream->device.close(stream->device.data);
		free(stream);
		return NULL;
	}
	stream->file = stream->fs.open(stream->volume, current);
	if (stream->file == NULL) {
		stream->fs.umount(stream->volume);
		stream->device.close(stream->device.data);
		free(stream);
		return NULL;
	}

	return stream;
}