package devmapper
/*
#cgo LDFLAGS: -L. -ldevmapper
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <libdevmapper.h>
#include <linux/loop.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/fs.h>
#include <errno.h>
#ifndef LOOP_CTL_GET_FREE
#define LOOP_CTL_GET_FREE 0x4C82
#endif
// FIXME: this could easily be rewritten in go
char* attach_loop_device(const char *filename, int *loop_fd_out)
{
struct loop_info64 loopinfo = {0};
struct stat st;
char buf[64];
int i, loop_fd, fd, start_index;
char* loopname;
*loop_fd_out = -1;
start_index = 0;
fd = open("/dev/loop-control", O_RDONLY);
if (fd >= 0) {
start_index = ioctl(fd, LOOP_CTL_GET_FREE);
close(fd);
if (start_index < 0)
start_index = 0;
}
fd = open(filename, O_RDWR);
if (fd < 0) {
perror("open");
return NULL;
}
loop_fd = -1;
for (i = start_index ; loop_fd < 0 ; i++ ) {
if (sprintf(buf, "/dev/loop%d", i) < 0) {
close(fd);
return NULL;
}
if (stat(buf, &st)) {
if (!S_ISBLK(st.st_mode)) {
fprintf(stderr, "[error] Loopback device %s is not a block device.\n", buf);
} else if (errno == ENOENT) {
fprintf(stderr, "[error] There are no more loopback device available.\n");
} else {
fprintf(stderr, "[error] Unkown error trying to stat the loopback device %s (errno: %d).\n", buf, errno);
}
close(fd);
return NULL;
}
loop_fd = open(buf, O_RDWR);
if (loop_fd < 0 && errno == ENOENT) {
fprintf(stderr, "[error] The loopback device %s does not exists.\n", buf);
close(fd);
return NULL;
} else if (loop_fd < 0) {
fprintf(stderr, "[error] Unkown error openning the loopback device %s. (errno: %d)\n", buf, errno);
continue;
}
if (ioctl(loop_fd, LOOP_SET_FD, (void *)(size_t)fd) < 0) {
int errsv = errno;
close(loop_fd);
loop_fd = -1;
if (errsv != EBUSY) {
close(fd);
fprintf(stderr, "cannot set up loopback device %s: %s", buf, strerror(errsv));
return NULL;
}
continue;
}
close(fd);
strncpy((char*)loopinfo.lo_file_name, buf, LO_NAME_SIZE);
loopinfo.lo_offset = 0;
loopinfo.lo_flags = LO_FLAGS_AUTOCLEAR;
if (ioctl(loop_fd, LOOP_SET_STATUS64, &loopinfo) < 0) {
perror("ioctl LOOP_SET_STATUS64");
if (ioctl(loop_fd, LOOP_CLR_FD, 0) < 0) {
perror("ioctl LOOP_CLR_FD");
}
close(loop_fd);
fprintf (stderr, "cannot set up loopback device info");
return (NULL);
}
loopname = strdup(buf);
if (loopname == NULL) {
close(loop_fd);
return (NULL);
}
*loop_fd_out = loop_fd;
return (loopname);
}
return (NULL);
}
extern void DevmapperLogCallback(int level, char *file, int line, int dm_errno_or_class, char *str);
static void log_cb(int level, const char *file, int line,
int dm_errno_or_class, const char *f, ...)
{
char buffer[256];
va_list ap;
va_start(ap, f);
vsnprintf(buffer, 256, f, ap);
va_end(ap);
DevmapperLogCallback(level, (char *)file, line, dm_errno_or_class, buffer);
}
static void log_with_errno_init()
{
dm_log_with_errno_init(log_cb);
}
*/
import "C"
import (
"unsafe"
)
type (
CDmTask C.struct_dm_task
)
var (
DmTaskDestory = dmTaskDestroyFct
DmTaskCreate = dmTaskCreateFct
DmTaskRun = dmTaskRunFct
DmTaskSetName = dmTaskSetNameFct
DmTaskSetMessage = dmTaskSetMessageFct
DmTaskSetSector = dmTaskSetSectorFct
DmTaskSetCookie = dmTaskSetCookieFct
DmTaskSetAddNode = dmTaskSetAddNodeFct
DmTaskSetRo = dmTaskSetRoFct
DmTaskAddTarget = dmTaskAddTargetFct
DmTaskGetInfo = dmTaskGetInfoFct
DmGetNextTarget = dmGetNextTargetFct
DmGetBlockSize = dmGetBlockSizeFct
DmAttachLoopDevice = dmAttachLoopDeviceFct
DmUdevWait = dmUdevWaitFct
DmLogInitVerbose = dmLogInitVerboseFct
DmSetDevDir = dmSetDevDirFct
DmGetLibraryVersion = dmGetLibraryVersionFct
LogWithErrnoInit = logWithErrnoInitFct
GetBlockSize = getBlockSizeFct
)
func free(p *C.char) {
C.free(unsafe.Pointer(p))
}
func dmTaskDestroyFct(task *CDmTask) {
C.dm_task_destroy((*C.struct_dm_task)(task))
}
func dmTaskCreateFct(taskType int) *CDmTask {
return (*CDmTask)(C.dm_task_create(C.int(taskType)))
}
func dmTaskRunFct(task *CDmTask) int {
return int(C.dm_task_run((*C.struct_dm_task)(task)))
}
func dmTaskSetNameFct(task *CDmTask, name string) int {
Cname := C.CString(name)
defer free(Cname)
return int(C.dm_task_set_name((*C.struct_dm_task)(task),
Cname))
}
func dmTaskSetMessageFct(task *CDmTask, message string) int {
Cmessage := C.CString(message)
defer free(Cmessage)
return int(C.dm_task_set_message((*C.struct_dm_task)(task),
Cmessage))
}
func dmTaskSetSectorFct(task *CDmTask, sector uint64) int {
return int(C.dm_task_set_sector((*C.struct_dm_task)(task),
C.uint64_t(sector)))
}
func dmTaskSetCookieFct(task *CDmTask, cookie *uint, flags uint16) int {
cCookie := C.uint32_t(*cookie)
defer func() {
*cookie = uint(cCookie)
}()
return int(C.dm_task_set_cookie((*C.struct_dm_task)(task), &cCookie,
C.uint16_t(flags)))
}
func dmTaskSetAddNodeFct(task *CDmTask, addNode AddNodeType) int {
return int(C.dm_task_set_add_node((*C.struct_dm_task)(task),
C.dm_add_node_t(addNode)))
}
func dmTaskSetRoFct(task *CDmTask) int {
return int(C.dm_task_set_ro((*C.struct_dm_task)(task)))
}
func dmTaskAddTargetFct(task *CDmTask,
start, size uint64, ttype, params string) int {
Cttype := C.CString(ttype)
defer free(Cttype)
Cparams := C.CString(params)
defer free(Cparams)
return int(C.dm_task_add_target((*C.struct_dm_task)(task),
C.uint64_t(start), C.uint64_t(size), Cttype, Cparams))
}
func dmGetLoopbackBackingFile(fd uintptr) (uint64, uint64, sysErrno) {
var lo64 C.struct_loop_info64
_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_GET_STATUS64,
uintptr(unsafe.Pointer(&lo64)))
return uint64(lo64.lo_device), uint64(lo64.lo_inode), sysErrno(err)
}
func dmLoopbackSetCapacity(fd uintptr) sysErrno {
_, _, err := sysSyscall(sysSysIoctl, fd, C.LOOP_SET_CAPACITY, 0)
return sysErrno(err)
}
func dmGetBlockSizeFct(fd uintptr) (int64, sysErrno) {
var size int64
_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
return size, sysErrno(err)
}
func dmTaskGetInfoFct(task *CDmTask, info *Info) int {
Cinfo := C.struct_dm_info{}
defer func() {
info.Exists = int(Cinfo.exists)
info.Suspended = int(Cinfo.suspended)
info.LiveTable = int(Cinfo.live_table)
info.InactiveTable = int(Cinfo.inactive_table)
info.OpenCount = int32(Cinfo.open_count)
info.EventNr = uint32(Cinfo.event_nr)
info.Major = uint32(Cinfo.major)
info.Minor = uint32(Cinfo.minor)
info.ReadOnly = int(Cinfo.read_only)
info.TargetCount = int32(Cinfo.target_count)
}()
return int(C.dm_task_get_info((*C.struct_dm_task)(task), &Cinfo))
}
func dmGetNextTargetFct(task *CDmTask, next uintptr, start, length *uint64, target, params *string) uintptr {
var (
Cstart, Clength C.uint64_t
CtargetType, Cparams *C.char
)
defer func() {
*start = uint64(Cstart)
*length = uint64(Clength)
*target = C.GoString(CtargetType)
*params = C.GoString(Cparams)
}()
nextp := C.dm_get_next_target((*C.struct_dm_task)(task),
unsafe.Pointer(next), &Cstart, &Clength, &CtargetType, &Cparams)
return uintptr(nextp)
}
func dmAttachLoopDeviceFct(filename string, fd *int) string {
cFilename := C.CString(filename)
defer free(cFilename)
var cFd C.int
defer func() {
*fd = int(cFd)
}()
ret := C.attach_loop_device(cFilename, &cFd)
defer free(ret)
return C.GoString(ret)
}
func getBlockSizeFct(fd uintptr, size *uint64) sysErrno {
_, _, err := sysSyscall(sysSysIoctl, fd, C.BLKGETSIZE64, uintptr(unsafe.Pointer(&size)))
return sysErrno(err)
}
func dmUdevWaitFct(cookie uint) int {
return int(C.dm_udev_wait(C.uint32_t(cookie)))
}
func dmLogInitVerboseFct(level int) {
C.dm_log_init_verbose(C.int(level))
}
func logWithErrnoInitFct() {
C.log_with_errno_init()
}
func dmSetDevDirFct(dir string) int {
Cdir := C.CString(dir)
defer free(Cdir)
return int(C.dm_set_dev_dir(Cdir))
}
func dmGetLibraryVersionFct(version *string) int {
buffer := C.CString(string(make([]byte, 128)))
defer free(buffer)
defer func() {
*version = C.GoString(buffer)
}()
return int(C.dm_get_library_version(buffer, 128))
}