1 /* 2 * valid_blk.c --- does the inode have valid blocks? 3 * 4 * Copyright 1997 by Theodore Ts'o 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Library 8 * General Public License, version 2. 9 * %End-Header% 10 */ 11 12 #include <stdio.h> 13 #if HAVE_UNISTD_H 14 #include <unistd.h> 15 #endif 16 #include <string.h> 17 #include <time.h> 18 19 #include "ext2_fs.h" 20 #include "ext2fs.h" 21 22 /* 23 * This function returns 1 if the inode's block entries actually 24 * contain block entries. 25 */ ext2fs_inode_has_valid_blocks2(ext2_filsys fs,struct ext2_inode * inode)26 int ext2fs_inode_has_valid_blocks2(ext2_filsys fs, struct ext2_inode *inode) 27 { 28 /* 29 * Only directories, regular files, and some symbolic links 30 * have valid block entries. 31 */ 32 if (!LINUX_S_ISDIR(inode->i_mode) && !LINUX_S_ISREG(inode->i_mode) && 33 !LINUX_S_ISLNK(inode->i_mode)) 34 return 0; 35 36 /* 37 * If the symbolic link is a "fast symlink", then the symlink 38 * target is stored in the block entries. 39 */ 40 if (LINUX_S_ISLNK (inode->i_mode)) { 41 if (ext2fs_file_acl_block(fs, inode) == 0) { 42 /* With no EA block, we can rely on i_blocks */ 43 if (inode->i_blocks == 0) 44 return 0; 45 } else { 46 /* With an EA block, life gets more tricky */ 47 if (inode->i_size >= EXT2_N_BLOCKS*4) 48 return 1; /* definitely using i_block[] */ 49 if (inode->i_size > 4 && inode->i_block[1] == 0) 50 return 1; /* definitely using i_block[] */ 51 return 0; /* Probably a fast symlink */ 52 } 53 } 54 return 1; 55 } 56 ext2fs_inode_has_valid_blocks(struct ext2_inode * inode)57 int ext2fs_inode_has_valid_blocks(struct ext2_inode *inode) 58 { 59 return ext2fs_inode_has_valid_blocks2(NULL, inode); 60 } 61