fsw_status_t fsw_posix_open_dno(struct fsw_posix_volume *pvol, const char *path, int required_type, struct fsw_shandle *shand)
{
fsw_status_t status;
struct fsw_dnode *dno;
struct fsw_dnode *target_dno;
struct fsw_string lookup_path;
lookup_path.type = FSW_STRING_TYPE_ISO88591;
lookup_path.len = strlen(path);
lookup_path.size = lookup_path.len;
lookup_path.data = (void *)path;
// resolve the path (symlinks along the way are automatically resolved)
status = fsw_dnode_lookup_path(pvol->vol->root, &lookup_path, '/', &dno);
if (status) {
fprintf(stderr, "fsw_posix_open_dno: fsw_dnode_lookup_path returned %d\n", status);
return status;
}
// if the final node is a symlink, also resolve it
status = fsw_dnode_resolve(dno, &target_dno);
fsw_dnode_release(dno);
if (status) {
fprintf(stderr, "fsw_posix_open_dno: fsw_dnode_resolve returned %d\n", status);
return status;
}
dno = target_dno;
// check that it is a regular file
status = fsw_dnode_fill(dno);
if (status) {
fprintf(stderr, "fsw_posix_open_dno: fsw_dnode_fill returned %d\n", status);
fsw_dnode_release(dno);
return status;
}
if (dno->type != required_type) {
fprintf(stderr, "fsw_posix_open_dno: dnode is not of the requested type\n");
fsw_dnode_release(dno);
return FSW_UNSUPPORTED;
}
// open shandle
status = fsw_shandle_open(dno, shand);
if (status) {
fprintf(stderr, "fsw_posix_open_dno: fsw_shandle_open returned %d\n", status);
}
fsw_dnode_release(dno);
return status;
}
fsw_status_t fsw_dnode_resolve(struct fsw_dnode *dno, struct fsw_dnode **target_dno_out)
{
fsw_status_t status;
struct fsw_string target_name;
struct fsw_dnode *target_dno;
/* Linux kernel max link count is 40 */
int link_count = 40;
fsw_dnode_retain(dno);
while (--link_count > 0) {
// get full information
status = fsw_dnode_fill(dno);
if (status)
goto errorexit;
if (dno->type != FSW_DNODE_TYPE_SYMLINK) {
// found a non-symlink target, return it
*target_dno_out = dno;
return FSW_SUCCESS;
}
if (dno->parent == NULL) { // safety measure, cannot happen in theory
status = FSW_NOT_FOUND;
goto errorexit;
}
// read the link's target
status = fsw_dnode_readlink(dno, &target_name);
if (status)
goto errorexit;
// resolve it
status = fsw_dnode_lookup_path(dno->parent, &target_name, '/', &target_dno);
fsw_strfree(&target_name);
if (status)
goto errorexit;
// target_dno becomes the new dno
fsw_dnode_release(dno);
dno = target_dno; // is already retained
}
if(link_count == 0)
status = FSW_NOT_FOUND;
errorexit:
fsw_dnode_release(dno);
return status;
}
EFI_STATUS fsw_efi_dir_open(IN FSW_FILE_DATA *File,
OUT EFI_FILE_PROTOCOL **NewHandle,
IN CHAR16 *FileName,
IN UINT64 OpenMode,
IN UINT64 Attributes)
{
EFI_STATUS Status;
FSW_VOLUME_DATA *Volume = (FSW_VOLUME_DATA *)File->shand.dnode->vol->host_data;
struct fsw_dnode *dno;
struct fsw_dnode *target_dno;
struct fsw_string lookup_path;
#if DEBUG_LEVEL
Print(L"fsw_efi_dir_open: '%s'\n", FileName);
#endif
if (OpenMode != EFI_FILE_MODE_READ)
return EFI_WRITE_PROTECTED;
lookup_path.type = FSW_STRING_TYPE_UTF16;
lookup_path.len = (int)StrLen(FileName);
lookup_path.size = lookup_path.len * sizeof(fsw_u16);
lookup_path.data = FileName;
// resolve the path (symlinks along the way are automatically resolved)
Status = fsw_efi_map_status(fsw_dnode_lookup_path(File->shand.dnode,
&lookup_path, '\\',
&dno),
Volume);
if (EFI_ERROR(Status))
return Status;
// if the final node is a symlink, also resolve it
Status = fsw_efi_map_status(fsw_dnode_resolve(dno, &target_dno),
Volume);
fsw_dnode_release(dno);
if (EFI_ERROR(Status))
return Status;
dno = target_dno;
// make a new EFI handle for the target dnode
Status = fsw_efi_dnode_to_FileHandle(dno, NewHandle);
fsw_dnode_release(dno);
return Status;
}
