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/* Interface between GRUB's fs drivers and application code */
#include <console/console.h>
#include <fs/fs.h>
#include <string.h>
#include <stdlib.h>
int filepos;
int filemax;
fs_error_t errnum;
void (*disk_read_hook) (int, int, int);
void (*disk_read_func) (int, int, int);
char FSYS_BUF[FSYS_BUFLEN];
int fsmax;
struct fsys_entry {
char *name;
int (*mount_func) (void);
int (*read_func) (char *buf, int len);
int (*dir_func) (char *dirname);
void (*close_func) (void);
int (*embed_func) (int *start_sector, int needed_sectors);
};
struct fsys_entry fsys_table[] = {
# if CONFIG_FS_FAT == 1
{"fat", fat_mount, fat_read, fat_dir, 0, 0},
# endif
# if CONFIG_FS_EXT2 == 1
{"ext2fs", ext2fs_mount, ext2fs_read, ext2fs_dir, 0, 0},
# endif
# if CONFIG_FS_ISO9660 == 1
{"iso9660", iso9660_mount, iso9660_read, iso9660_dir, 0, 0},
# endif
};
/* NULLFS is used to read images from raw device */
static int nullfs_dir(char *name)
{
uint64_t dev_size;
if (name) {
printk_debug("can't have a named file\n");
return 0;
}
dev_size = (uint64_t) part_length << 9;
/* GRUB code doesn't like 2GB or bigger files */
if (dev_size > 0x7fffffff)
dev_size = 0x7fffffff;
filemax = dev_size;
return 1;
}
static int nullfs_read(char *buf, int len)
{
if (devread(filepos>>9, filepos&0x1ff, len, buf)) {
filepos += len;
return len;
} else
return 0;
}
static struct fsys_entry nullfs =
{"nullfs", 0, nullfs_read, nullfs_dir, 0, 0};
static struct fsys_entry *fsys;
int mount_fs(void)
{
int i;
for (i = 0; i < sizeof(fsys_table)/sizeof(fsys_table[0]); i++) {
if (fsys_table[i].mount_func()) {
fsys = &fsys_table[i];
printk_info("Mounted %s\n", fsys->name);
return 1;
}
}
fsys = 0;
printk_info("Unknown filesystem type\n");
return 0;
}
int file_open(const char *filename)
{
char *dev = 0;
const char *path;
int len;
int retval = 0;
int reopen;
path = strchr(filename, ':');
if (path) {
len = path - filename;
path++;
dev = malloc(len + 1);
memcpy(dev, filename, len);
dev[len] = '\0';
} else {
/* No colon is given. Is this device or filename? */
if (filename[0] == '/') {
/* Anything starts with '/' must be a filename */
dev = 0;
path = filename;
} else {
dev = strdup(filename);
path = 0;
}
}
if (dev && dev[0]) {
if (!devopen(dev, &reopen)) {
fsys = 0;
goto out;
}
if (!reopen)
fsys = 0;
}
if (path) {
if (!fsys || fsys==&nullfs) {
if (!mount_fs())
goto out;
}
using_devsize = 0;
if (!path[0]) {
printk_info("No filename is given\n");
goto out;
}
} else
fsys = &nullfs;
filepos = 0;
errnum = 0;
if (!fsys->dir_func((char *) path)) {
printk_info("File not found\n");
goto out;
}
retval = 1;
out:
if (dev)
free(dev);
return retval;
}
int file_read(void *buf, unsigned long len)
{
if (filepos < 0 || filepos > filemax)
filepos = filemax;
if (len < 0 || len > filemax-filepos)
len = filemax - filepos;
errnum = 0;
return fsys->read_func(buf, len);
}
int file_seek(unsigned long offset)
{
filepos = offset;
return filepos;
}
unsigned long file_pos(void)
{
return filepos;
}
unsigned long file_size(void)
{
return filemax;
}
void file_close(void)
{
}
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