[821] | 1 | /*
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| 2 | * inode.c --- utility routines to read and write inodes
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| 3 | *
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| 4 | * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o.
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| 5 | *
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| 6 | * %Begin-Header%
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| 7 | * This file may be redistributed under the terms of the GNU Public
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| 8 | * License.
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| 9 | * %End-Header%
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| 10 | */
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| 11 |
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| 12 | #include <stdio.h>
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| 13 | #include <string.h>
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| 14 | #if HAVE_UNISTD_H
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| 15 | #include <unistd.h>
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| 16 | #endif
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| 17 | #if HAVE_ERRNO_H
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| 18 | #include <errno.h>
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| 19 | #endif
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| 20 | #if HAVE_SYS_STAT_H
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| 21 | #include <sys/stat.h>
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| 22 | #endif
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| 23 | #if HAVE_SYS_TYPES_H
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| 24 | #include <sys/types.h>
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| 25 | #endif
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| 26 |
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| 27 | #include "ext2_fs.h"
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| 28 | #include "ext2fsP.h"
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| 29 | #include "e2image.h"
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| 30 |
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| 31 | struct ext2_struct_inode_scan {
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| 32 | errcode_t magic;
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| 33 | ext2_filsys fs;
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| 34 | ext2_ino_t current_inode;
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| 35 | blk_t current_block;
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| 36 | dgrp_t current_group;
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| 37 | ext2_ino_t inodes_left;
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| 38 | blk_t blocks_left;
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| 39 | dgrp_t groups_left;
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| 40 | blk_t inode_buffer_blocks;
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| 41 | char * inode_buffer;
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| 42 | int inode_size;
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| 43 | char * ptr;
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| 44 | int bytes_left;
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| 45 | char *temp_buffer;
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| 46 | errcode_t (*done_group)(ext2_filsys fs,
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| 47 | dgrp_t group,
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| 48 | void * priv_data);
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| 49 | void * done_group_data;
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| 50 | int bad_block_ptr;
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| 51 | int scan_flags;
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| 52 | int reserved[6];
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| 53 | };
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| 54 |
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| 55 | /*
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| 56 | * This routine flushes the icache, if it exists.
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| 57 | */
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| 58 | errcode_t ext2fs_flush_icache(ext2_filsys fs)
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| 59 | {
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| 60 | int i;
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| 61 |
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| 62 | if (!fs->icache)
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| 63 | return 0;
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| 64 |
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| 65 | for (i=0; i < fs->icache->cache_size; i++)
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| 66 | fs->icache->cache[i].ino = 0;
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| 67 |
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| 68 | fs->icache->buffer_blk = 0;
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| 69 | return 0;
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| 70 | }
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| 71 |
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| 72 | static errcode_t create_icache(ext2_filsys fs)
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| 73 | {
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| 74 | errcode_t retval;
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| 75 |
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| 76 | if (fs->icache)
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| 77 | return 0;
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| 78 | retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache);
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| 79 | if (retval)
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| 80 | return retval;
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| 81 |
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| 82 | memset(fs->icache, 0, sizeof(struct ext2_inode_cache));
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| 83 | retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer);
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| 84 | if (retval) {
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| 85 | ext2fs_free_mem(&fs->icache);
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| 86 | return retval;
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| 87 | }
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| 88 | fs->icache->buffer_blk = 0;
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| 89 | fs->icache->cache_last = -1;
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| 90 | fs->icache->cache_size = 4;
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| 91 | fs->icache->refcount = 1;
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| 92 | retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache_ent)
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| 93 | * fs->icache->cache_size,
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| 94 | &fs->icache->cache);
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| 95 | if (retval) {
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| 96 | ext2fs_free_mem(&fs->icache->buffer);
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| 97 | ext2fs_free_mem(&fs->icache);
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| 98 | return retval;
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| 99 | }
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| 100 | ext2fs_flush_icache(fs);
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| 101 | return 0;
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| 102 | }
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| 103 |
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| 104 | errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks,
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| 105 | ext2_inode_scan *ret_scan)
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| 106 | {
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| 107 | ext2_inode_scan scan;
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| 108 | errcode_t retval;
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| 109 | errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks);
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| 110 |
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| 111 | EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
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| 112 |
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| 113 | /*
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| 114 | * If fs->badblocks isn't set, then set it --- since the inode
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| 115 | * scanning functions require it.
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| 116 | */
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| 117 | if (fs->badblocks == 0) {
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| 118 | /*
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| 119 | * Temporarly save fs->get_blocks and set it to zero,
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| 120 | * for compatibility with old e2fsck's.
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| 121 | */
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| 122 | save_get_blocks = fs->get_blocks;
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| 123 | fs->get_blocks = 0;
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| 124 | retval = ext2fs_read_bb_inode(fs, &fs->badblocks);
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| 125 | if (retval) {
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| 126 | ext2fs_badblocks_list_free(fs->badblocks);
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| 127 | fs->badblocks = 0;
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| 128 | }
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| 129 | fs->get_blocks = save_get_blocks;
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| 130 | }
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| 131 |
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| 132 | retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan);
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| 133 | if (retval)
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| 134 | return retval;
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| 135 | memset(scan, 0, sizeof(struct ext2_struct_inode_scan));
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| 136 |
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| 137 | scan->magic = EXT2_ET_MAGIC_INODE_SCAN;
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| 138 | scan->fs = fs;
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| 139 | scan->inode_size = EXT2_INODE_SIZE(fs->super);
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| 140 | scan->bytes_left = 0;
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| 141 | scan->current_group = 0;
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| 142 | scan->groups_left = fs->group_desc_count - 1;
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| 143 | scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8;
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| 144 | scan->current_block = scan->fs->
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| 145 | group_desc[scan->current_group].bg_inode_table;
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| 146 | scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
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| 147 | scan->blocks_left = scan->fs->inode_blocks_per_group;
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| 148 | retval = ext2fs_get_mem((size_t) (scan->inode_buffer_blocks *
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| 149 | fs->blocksize),
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| 150 | &scan->inode_buffer);
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| 151 | scan->done_group = 0;
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| 152 | scan->done_group_data = 0;
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| 153 | scan->bad_block_ptr = 0;
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| 154 | if (retval) {
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| 155 | ext2fs_free_mem(&scan);
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| 156 | return retval;
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| 157 | }
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| 158 | retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer);
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| 159 | if (retval) {
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| 160 | ext2fs_free_mem(&scan->inode_buffer);
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| 161 | ext2fs_free_mem(&scan);
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| 162 | return retval;
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| 163 | }
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| 164 | if (scan->fs->badblocks && scan->fs->badblocks->num)
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| 165 | scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS;
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| 166 | *ret_scan = scan;
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| 167 | return 0;
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| 168 | }
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| 169 |
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| 170 | void ext2fs_close_inode_scan(ext2_inode_scan scan)
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| 171 | {
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| 172 | if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
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| 173 | return;
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| 174 |
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| 175 | ext2fs_free_mem(&scan->inode_buffer);
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| 176 | scan->inode_buffer = NULL;
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| 177 | ext2fs_free_mem(&scan->temp_buffer);
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| 178 | scan->temp_buffer = NULL;
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| 179 | ext2fs_free_mem(&scan);
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| 180 | return;
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| 181 | }
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| 182 |
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| 183 | void ext2fs_set_inode_callback(ext2_inode_scan scan,
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| 184 | errcode_t (*done_group)(ext2_filsys fs,
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| 185 | dgrp_t group,
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| 186 | void * priv_data),
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| 187 | void *done_group_data)
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| 188 | {
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| 189 | if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
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| 190 | return;
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| 191 |
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| 192 | scan->done_group = done_group;
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| 193 | scan->done_group_data = done_group_data;
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| 194 | }
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| 195 |
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| 196 | int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags,
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| 197 | int clear_flags)
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| 198 | {
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| 199 | int old_flags;
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| 200 |
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| 201 | if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
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| 202 | return 0;
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| 203 |
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| 204 | old_flags = scan->scan_flags;
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| 205 | scan->scan_flags &= ~clear_flags;
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| 206 | scan->scan_flags |= set_flags;
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| 207 | return old_flags;
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| 208 | }
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| 209 |
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| 210 | /*
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| 211 | * This function is called by ext2fs_get_next_inode when it needs to
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| 212 | * get ready to read in a new blockgroup.
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| 213 | */
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| 214 | static errcode_t get_next_blockgroup(ext2_inode_scan scan)
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| 215 | {
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| 216 | scan->current_group++;
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| 217 | scan->groups_left--;
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| 218 |
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| 219 | scan->current_block = scan->fs->
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| 220 | group_desc[scan->current_group].bg_inode_table;
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| 221 |
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| 222 | scan->current_inode = scan->current_group *
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| 223 | EXT2_INODES_PER_GROUP(scan->fs->super);
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| 224 |
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| 225 | scan->bytes_left = 0;
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| 226 | scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
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| 227 | scan->blocks_left = scan->fs->inode_blocks_per_group;
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| 228 | return 0;
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| 229 | }
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| 230 |
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| 231 | errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan,
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| 232 | int group)
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| 233 | {
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| 234 | scan->current_group = group - 1;
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| 235 | scan->groups_left = scan->fs->group_desc_count - group;
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| 236 | return get_next_blockgroup(scan);
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| 237 | }
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| 238 |
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| 239 | /*
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| 240 | * This function is called by get_next_blocks() to check for bad
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| 241 | * blocks in the inode table.
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| 242 | *
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| 243 | * This function assumes that badblocks_list->list is sorted in
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| 244 | * increasing order.
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| 245 | */
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| 246 | static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan,
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| 247 | blk_t *num_blocks)
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| 248 | {
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| 249 | blk_t blk = scan->current_block;
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| 250 | badblocks_list bb = scan->fs->badblocks;
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| 251 |
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| 252 | /*
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| 253 | * If the inode table is missing, then obviously there are no
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| 254 | * bad blocks. :-)
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| 255 | */
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| 256 | if (blk == 0)
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| 257 | return 0;
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| 258 |
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| 259 | /*
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| 260 | * If the current block is greater than the bad block listed
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| 261 | * in the bad block list, then advance the pointer until this
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| 262 | * is no longer the case. If we run out of bad blocks, then
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| 263 | * we don't need to do any more checking!
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| 264 | */
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| 265 | while (blk > bb->list[scan->bad_block_ptr]) {
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| 266 | if (++scan->bad_block_ptr >= bb->num) {
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| 267 | scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
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| 268 | return 0;
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| 269 | }
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| 270 | }
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| 271 |
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| 272 | /*
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| 273 | * If the current block is equal to the bad block listed in
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| 274 | * the bad block list, then handle that one block specially.
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| 275 | * (We could try to handle runs of bad blocks, but that
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| 276 | * only increases CPU efficiency by a small amount, at the
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| 277 | * expense of a huge expense of code complexity, and for an
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| 278 | * uncommon case at that.)
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| 279 | */
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| 280 | if (blk == bb->list[scan->bad_block_ptr]) {
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| 281 | scan->scan_flags |= EXT2_SF_BAD_INODE_BLK;
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| 282 | *num_blocks = 1;
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| 283 | if (++scan->bad_block_ptr >= bb->num)
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| 284 | scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
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| 285 | return 0;
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| 286 | }
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| 287 |
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| 288 | /*
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| 289 | * If there is a bad block in the range that we're about to
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| 290 | * read in, adjust the number of blocks to read so that we we
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| 291 | * don't read in the bad block. (Then the next block to read
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| 292 | * will be the bad block, which is handled in the above case.)
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| 293 | */
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| 294 | if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr])
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| 295 | *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk);
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| 296 |
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| 297 | return 0;
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| 298 | }
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| 299 |
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| 300 | /*
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| 301 | * This function is called by ext2fs_get_next_inode when it needs to
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| 302 | * read in more blocks from the current blockgroup's inode table.
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| 303 | */
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| 304 | static errcode_t get_next_blocks(ext2_inode_scan scan)
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| 305 | {
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| 306 | blk_t num_blocks;
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| 307 | errcode_t retval;
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| 308 |
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| 309 | /*
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| 310 | * Figure out how many blocks to read; we read at most
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| 311 | * inode_buffer_blocks, and perhaps less if there aren't that
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| 312 | * many blocks left to read.
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| 313 | */
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| 314 | num_blocks = scan->inode_buffer_blocks;
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| 315 | if (num_blocks > scan->blocks_left)
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| 316 | num_blocks = scan->blocks_left;
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| 317 |
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| 318 | /*
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| 319 | * If the past block "read" was a bad block, then mark the
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| 320 | * left-over extra bytes as also being bad.
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| 321 | */
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| 322 | if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) {
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| 323 | if (scan->bytes_left)
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| 324 | scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES;
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| 325 | scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK;
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| 326 | }
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| 327 |
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| 328 | /*
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| 329 | * Do inode bad block processing, if necessary.
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| 330 | */
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| 331 | if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) {
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| 332 | retval = check_for_inode_bad_blocks(scan, &num_blocks);
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| 333 | if (retval)
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| 334 | return retval;
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| 335 | }
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| 336 |
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| 337 | if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) ||
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| 338 | (scan->current_block == 0)) {
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| 339 | memset(scan->inode_buffer, 0,
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| 340 | (size_t) num_blocks * scan->fs->blocksize);
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| 341 | } else {
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| 342 | retval = io_channel_read_blk(scan->fs->io,
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| 343 | scan->current_block,
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| 344 | (int) num_blocks,
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| 345 | scan->inode_buffer);
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| 346 | if (retval)
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| 347 | return EXT2_ET_NEXT_INODE_READ;
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| 348 | }
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| 349 | scan->ptr = scan->inode_buffer;
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| 350 | scan->bytes_left = num_blocks * scan->fs->blocksize;
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| 351 |
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| 352 | scan->blocks_left -= num_blocks;
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| 353 | if (scan->current_block)
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| 354 | scan->current_block += num_blocks;
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| 355 | return 0;
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| 356 | }
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| 357 |
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| 358 | #if 0
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| 359 | /*
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| 360 | * Returns 1 if the entire inode_buffer has a non-zero size and
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| 361 | * contains all zeros. (Not just deleted inodes, since that means
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| 362 | * that part of the inode table was used at one point; we want all
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| 363 | * zeros, which means that the inode table is pristine.)
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| 364 | */
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| 365 | static inline int is_empty_scan(ext2_inode_scan scan)
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| 366 | {
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| 367 | int i;
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| 368 |
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| 369 | if (scan->bytes_left == 0)
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| 370 | return 0;
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| 371 |
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| 372 | for (i=0; i < scan->bytes_left; i++)
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| 373 | if (scan->ptr[i])
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| 374 | return 0;
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| 375 | return 1;
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| 376 | }
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| 377 | #endif
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| 378 |
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| 379 | errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino,
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| 380 | struct ext2_inode *inode, int bufsize)
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| 381 | {
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| 382 | errcode_t retval;
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| 383 | int extra_bytes = 0;
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| 384 |
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| 385 | EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN);
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| 386 |
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| 387 | /*
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| 388 | * Do we need to start reading a new block group?
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| 389 | */
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| 390 | if (scan->inodes_left <= 0) {
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| 391 | force_new_group:
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| 392 | if (scan->done_group) {
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| 393 | retval = (scan->done_group)
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| 394 | (scan->fs, scan->current_group,
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| 395 | scan->done_group_data);
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| 396 | if (retval)
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| 397 | return retval;
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| 398 | }
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| 399 | if (scan->groups_left <= 0) {
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| 400 | *ino = 0;
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| 401 | return 0;
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| 402 | }
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| 403 | retval = get_next_blockgroup(scan);
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| 404 | if (retval)
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| 405 | return retval;
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| 406 | }
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| 407 | /*
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| 408 | * This is done outside the above if statement so that the
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| 409 | * check can be done for block group #0.
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| 410 | */
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| 411 | if (scan->current_block == 0) {
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| 412 | if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) {
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| 413 | goto force_new_group;
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| 414 | } else
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| 415 | return EXT2_ET_MISSING_INODE_TABLE;
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| 416 | }
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| 417 |
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| 418 |
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| 419 | /*
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| 420 | * Have we run out of space in the inode buffer? If so, we
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| 421 | * need to read in more blocks.
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| 422 | */
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| 423 | if (scan->bytes_left < scan->inode_size) {
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| 424 | memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left);
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| 425 | extra_bytes = scan->bytes_left;
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| 426 |
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| 427 | retval = get_next_blocks(scan);
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| 428 | if (retval)
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| 429 | return retval;
|
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| 430 | #if 0
|
---|
| 431 | /*
|
---|
| 432 | * XXX test Need check for used inode somehow.
|
---|
| 433 | * (Note: this is hard.)
|
---|
| 434 | */
|
---|
| 435 | if (is_empty_scan(scan))
|
---|
| 436 | goto force_new_group;
|
---|
| 437 | #endif
|
---|
| 438 | }
|
---|
| 439 |
|
---|
| 440 | retval = 0;
|
---|
| 441 | if (extra_bytes) {
|
---|
| 442 | memcpy(scan->temp_buffer+extra_bytes, scan->ptr,
|
---|
| 443 | scan->inode_size - extra_bytes);
|
---|
| 444 | scan->ptr += scan->inode_size - extra_bytes;
|
---|
| 445 | scan->bytes_left -= scan->inode_size - extra_bytes;
|
---|
| 446 |
|
---|
| 447 | #if BB_BIG_ENDIAN
|
---|
| 448 | if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
|
---|
| 449 | (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
|
---|
| 450 | ext2fs_swap_inode_full(scan->fs,
|
---|
| 451 | (struct ext2_inode_large *) inode,
|
---|
| 452 | (struct ext2_inode_large *) scan->temp_buffer,
|
---|
| 453 | 0, bufsize);
|
---|
| 454 | else
|
---|
| 455 | #endif
|
---|
| 456 | *inode = *((struct ext2_inode *) scan->temp_buffer);
|
---|
| 457 | if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES)
|
---|
| 458 | retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
|
---|
| 459 | scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES;
|
---|
| 460 | } else {
|
---|
| 461 | #if BB_BIG_ENDIAN
|
---|
| 462 | if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
|
---|
| 463 | (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
|
---|
| 464 | ext2fs_swap_inode_full(scan->fs,
|
---|
| 465 | (struct ext2_inode_large *) inode,
|
---|
| 466 | (struct ext2_inode_large *) scan->ptr,
|
---|
| 467 | 0, bufsize);
|
---|
| 468 | else
|
---|
| 469 | #endif
|
---|
| 470 | memcpy(inode, scan->ptr, bufsize);
|
---|
| 471 | scan->ptr += scan->inode_size;
|
---|
| 472 | scan->bytes_left -= scan->inode_size;
|
---|
| 473 | if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK)
|
---|
| 474 | retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
|
---|
| 475 | }
|
---|
| 476 |
|
---|
| 477 | scan->inodes_left--;
|
---|
| 478 | scan->current_inode++;
|
---|
| 479 | *ino = scan->current_inode;
|
---|
| 480 | return retval;
|
---|
| 481 | }
|
---|
| 482 |
|
---|
| 483 | errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino,
|
---|
| 484 | struct ext2_inode *inode)
|
---|
| 485 | {
|
---|
| 486 | return ext2fs_get_next_inode_full(scan, ino, inode,
|
---|
| 487 | sizeof(struct ext2_inode));
|
---|
| 488 | }
|
---|
| 489 |
|
---|
| 490 | /*
|
---|
| 491 | * Functions to read and write a single inode.
|
---|
| 492 | */
|
---|
| 493 | errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino,
|
---|
| 494 | struct ext2_inode * inode, int bufsize)
|
---|
| 495 | {
|
---|
| 496 | unsigned long group, block, block_nr, offset;
|
---|
| 497 | char *ptr;
|
---|
| 498 | errcode_t retval;
|
---|
| 499 | int clen, i, inodes_per_block, length;
|
---|
| 500 | io_channel io;
|
---|
| 501 |
|
---|
| 502 | EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
---|
| 503 |
|
---|
| 504 | /* Check to see if user has an override function */
|
---|
| 505 | if (fs->read_inode) {
|
---|
| 506 | retval = (fs->read_inode)(fs, ino, inode);
|
---|
| 507 | if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
|
---|
| 508 | return retval;
|
---|
| 509 | }
|
---|
| 510 | /* Create inode cache if not present */
|
---|
| 511 | if (!fs->icache) {
|
---|
| 512 | retval = create_icache(fs);
|
---|
| 513 | if (retval)
|
---|
| 514 | return retval;
|
---|
| 515 | }
|
---|
| 516 | /* Check to see if it's in the inode cache */
|
---|
| 517 | if (bufsize == sizeof(struct ext2_inode)) {
|
---|
| 518 | /* only old good inode can be retrieve from the cache */
|
---|
| 519 | for (i=0; i < fs->icache->cache_size; i++) {
|
---|
| 520 | if (fs->icache->cache[i].ino == ino) {
|
---|
| 521 | *inode = fs->icache->cache[i].inode;
|
---|
| 522 | return 0;
|
---|
| 523 | }
|
---|
| 524 | }
|
---|
| 525 | }
|
---|
| 526 | if ((ino == 0) || (ino > fs->super->s_inodes_count))
|
---|
| 527 | return EXT2_ET_BAD_INODE_NUM;
|
---|
| 528 | if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
|
---|
| 529 | inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super);
|
---|
| 530 | block_nr = fs->image_header->offset_inode / fs->blocksize;
|
---|
| 531 | block_nr += (ino - 1) / inodes_per_block;
|
---|
| 532 | offset = ((ino - 1) % inodes_per_block) *
|
---|
| 533 | EXT2_INODE_SIZE(fs->super);
|
---|
| 534 | io = fs->image_io;
|
---|
| 535 | } else {
|
---|
| 536 | group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
|
---|
| 537 | offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
|
---|
| 538 | EXT2_INODE_SIZE(fs->super);
|
---|
| 539 | block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
|
---|
| 540 | if (!fs->group_desc[(unsigned)group].bg_inode_table)
|
---|
| 541 | return EXT2_ET_MISSING_INODE_TABLE;
|
---|
| 542 | block_nr = fs->group_desc[(unsigned)group].bg_inode_table +
|
---|
| 543 | block;
|
---|
| 544 | io = fs->io;
|
---|
| 545 | }
|
---|
| 546 | offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
|
---|
| 547 |
|
---|
| 548 | length = EXT2_INODE_SIZE(fs->super);
|
---|
| 549 | if (bufsize < length)
|
---|
| 550 | length = bufsize;
|
---|
| 551 |
|
---|
| 552 | ptr = (char *) inode;
|
---|
| 553 | while (length) {
|
---|
| 554 | clen = length;
|
---|
| 555 | if ((offset + length) > fs->blocksize)
|
---|
| 556 | clen = fs->blocksize - offset;
|
---|
| 557 |
|
---|
| 558 | if (block_nr != fs->icache->buffer_blk) {
|
---|
| 559 | retval = io_channel_read_blk(io, block_nr, 1,
|
---|
| 560 | fs->icache->buffer);
|
---|
| 561 | if (retval)
|
---|
| 562 | return retval;
|
---|
| 563 | fs->icache->buffer_blk = block_nr;
|
---|
| 564 | }
|
---|
| 565 |
|
---|
| 566 | memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset,
|
---|
| 567 | clen);
|
---|
| 568 |
|
---|
| 569 | offset = 0;
|
---|
| 570 | length -= clen;
|
---|
| 571 | ptr += clen;
|
---|
| 572 | block_nr++;
|
---|
| 573 | }
|
---|
| 574 |
|
---|
| 575 | #if BB_BIG_ENDIAN
|
---|
| 576 | if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
|
---|
| 577 | (fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
|
---|
| 578 | ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode,
|
---|
| 579 | (struct ext2_inode_large *) inode,
|
---|
| 580 | 0, length);
|
---|
| 581 | #endif
|
---|
| 582 |
|
---|
| 583 | /* Update the inode cache */
|
---|
| 584 | fs->icache->cache_last = (fs->icache->cache_last + 1) %
|
---|
| 585 | fs->icache->cache_size;
|
---|
| 586 | fs->icache->cache[fs->icache->cache_last].ino = ino;
|
---|
| 587 | fs->icache->cache[fs->icache->cache_last].inode = *inode;
|
---|
| 588 |
|
---|
| 589 | return 0;
|
---|
| 590 | }
|
---|
| 591 |
|
---|
| 592 | errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino,
|
---|
| 593 | struct ext2_inode * inode)
|
---|
| 594 | {
|
---|
| 595 | return ext2fs_read_inode_full(fs, ino, inode,
|
---|
| 596 | sizeof(struct ext2_inode));
|
---|
| 597 | }
|
---|
| 598 |
|
---|
| 599 | errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino,
|
---|
| 600 | struct ext2_inode * inode, int bufsize)
|
---|
| 601 | {
|
---|
| 602 | unsigned long group, block, block_nr, offset;
|
---|
| 603 | errcode_t retval = 0;
|
---|
| 604 | struct ext2_inode_large temp_inode, *w_inode;
|
---|
| 605 | char *ptr;
|
---|
| 606 | int clen, i, length;
|
---|
| 607 |
|
---|
| 608 | EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
---|
| 609 |
|
---|
| 610 | /* Check to see if user provided an override function */
|
---|
| 611 | if (fs->write_inode) {
|
---|
| 612 | retval = (fs->write_inode)(fs, ino, inode);
|
---|
| 613 | if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
|
---|
| 614 | return retval;
|
---|
| 615 | }
|
---|
| 616 |
|
---|
| 617 | /* Check to see if the inode cache needs to be updated */
|
---|
| 618 | if (fs->icache) {
|
---|
| 619 | for (i=0; i < fs->icache->cache_size; i++) {
|
---|
| 620 | if (fs->icache->cache[i].ino == ino) {
|
---|
| 621 | fs->icache->cache[i].inode = *inode;
|
---|
| 622 | break;
|
---|
| 623 | }
|
---|
| 624 | }
|
---|
| 625 | } else {
|
---|
| 626 | retval = create_icache(fs);
|
---|
| 627 | if (retval)
|
---|
| 628 | return retval;
|
---|
| 629 | }
|
---|
| 630 |
|
---|
| 631 | if (!(fs->flags & EXT2_FLAG_RW))
|
---|
| 632 | return EXT2_ET_RO_FILSYS;
|
---|
| 633 |
|
---|
| 634 | if ((ino == 0) || (ino > fs->super->s_inodes_count))
|
---|
| 635 | return EXT2_ET_BAD_INODE_NUM;
|
---|
| 636 |
|
---|
| 637 | length = bufsize;
|
---|
| 638 | if (length < EXT2_INODE_SIZE(fs->super))
|
---|
| 639 | length = EXT2_INODE_SIZE(fs->super);
|
---|
| 640 |
|
---|
| 641 | if (length > (int) sizeof(struct ext2_inode_large)) {
|
---|
| 642 | w_inode = xmalloc(length);
|
---|
| 643 | } else
|
---|
| 644 | w_inode = &temp_inode;
|
---|
| 645 | memset(w_inode, 0, length);
|
---|
| 646 |
|
---|
| 647 | #if BB_BIG_ENDIAN
|
---|
| 648 | if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
|
---|
| 649 | (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE))
|
---|
| 650 | ext2fs_swap_inode_full(fs, w_inode,
|
---|
| 651 | (struct ext2_inode_large *) inode,
|
---|
| 652 | 1, bufsize);
|
---|
| 653 | else
|
---|
| 654 | #endif
|
---|
| 655 | memcpy(w_inode, inode, bufsize);
|
---|
| 656 |
|
---|
| 657 | group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
|
---|
| 658 | offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
|
---|
| 659 | EXT2_INODE_SIZE(fs->super);
|
---|
| 660 | block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
|
---|
| 661 | if (!fs->group_desc[(unsigned) group].bg_inode_table)
|
---|
| 662 | return EXT2_ET_MISSING_INODE_TABLE;
|
---|
| 663 | block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block;
|
---|
| 664 |
|
---|
| 665 | offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
|
---|
| 666 |
|
---|
| 667 | length = EXT2_INODE_SIZE(fs->super);
|
---|
| 668 | if (length > bufsize)
|
---|
| 669 | length = bufsize;
|
---|
| 670 |
|
---|
| 671 | ptr = (char *) w_inode;
|
---|
| 672 |
|
---|
| 673 | while (length) {
|
---|
| 674 | clen = length;
|
---|
| 675 | if ((offset + length) > fs->blocksize)
|
---|
| 676 | clen = fs->blocksize - offset;
|
---|
| 677 |
|
---|
| 678 | if (fs->icache->buffer_blk != block_nr) {
|
---|
| 679 | retval = io_channel_read_blk(fs->io, block_nr, 1,
|
---|
| 680 | fs->icache->buffer);
|
---|
| 681 | if (retval)
|
---|
| 682 | goto errout;
|
---|
| 683 | fs->icache->buffer_blk = block_nr;
|
---|
| 684 | }
|
---|
| 685 |
|
---|
| 686 |
|
---|
| 687 | memcpy((char *) fs->icache->buffer + (unsigned) offset,
|
---|
| 688 | ptr, clen);
|
---|
| 689 |
|
---|
| 690 | retval = io_channel_write_blk(fs->io, block_nr, 1,
|
---|
| 691 | fs->icache->buffer);
|
---|
| 692 | if (retval)
|
---|
| 693 | goto errout;
|
---|
| 694 |
|
---|
| 695 | offset = 0;
|
---|
| 696 | ptr += clen;
|
---|
| 697 | length -= clen;
|
---|
| 698 | block_nr++;
|
---|
| 699 | }
|
---|
| 700 |
|
---|
| 701 | fs->flags |= EXT2_FLAG_CHANGED;
|
---|
| 702 | errout:
|
---|
| 703 | if (w_inode && w_inode != &temp_inode)
|
---|
| 704 | free(w_inode);
|
---|
| 705 | return retval;
|
---|
| 706 | }
|
---|
| 707 |
|
---|
| 708 | errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino,
|
---|
| 709 | struct ext2_inode *inode)
|
---|
| 710 | {
|
---|
| 711 | return ext2fs_write_inode_full(fs, ino, inode,
|
---|
| 712 | sizeof(struct ext2_inode));
|
---|
| 713 | }
|
---|
| 714 |
|
---|
| 715 | /*
|
---|
| 716 | * This function should be called when writing a new inode. It makes
|
---|
| 717 | * sure that extra part of large inodes is initialized properly.
|
---|
| 718 | */
|
---|
| 719 | errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino,
|
---|
| 720 | struct ext2_inode *inode)
|
---|
| 721 | {
|
---|
| 722 | struct ext2_inode *buf;
|
---|
| 723 | int size = EXT2_INODE_SIZE(fs->super);
|
---|
| 724 | struct ext2_inode_large *large_inode;
|
---|
| 725 |
|
---|
| 726 | if (size == sizeof(struct ext2_inode))
|
---|
| 727 | return ext2fs_write_inode_full(fs, ino, inode,
|
---|
| 728 | sizeof(struct ext2_inode));
|
---|
| 729 |
|
---|
| 730 | buf = xmalloc(size);
|
---|
| 731 |
|
---|
| 732 | memset(buf, 0, size);
|
---|
| 733 | *buf = *inode;
|
---|
| 734 |
|
---|
| 735 | large_inode = (struct ext2_inode_large *) buf;
|
---|
| 736 | large_inode->i_extra_isize = sizeof(struct ext2_inode_large) -
|
---|
| 737 | EXT2_GOOD_OLD_INODE_SIZE;
|
---|
| 738 |
|
---|
| 739 | return ext2fs_write_inode_full(fs, ino, buf, size);
|
---|
| 740 | }
|
---|
| 741 |
|
---|
| 742 |
|
---|
| 743 | errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks)
|
---|
| 744 | {
|
---|
| 745 | struct ext2_inode inode;
|
---|
| 746 | int i;
|
---|
| 747 | errcode_t retval;
|
---|
| 748 |
|
---|
| 749 | EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
---|
| 750 |
|
---|
| 751 | if (ino > fs->super->s_inodes_count)
|
---|
| 752 | return EXT2_ET_BAD_INODE_NUM;
|
---|
| 753 |
|
---|
| 754 | if (fs->get_blocks) {
|
---|
| 755 | if (!(*fs->get_blocks)(fs, ino, blocks))
|
---|
| 756 | return 0;
|
---|
| 757 | }
|
---|
| 758 | retval = ext2fs_read_inode(fs, ino, &inode);
|
---|
| 759 | if (retval)
|
---|
| 760 | return retval;
|
---|
| 761 | for (i=0; i < EXT2_N_BLOCKS; i++)
|
---|
| 762 | blocks[i] = inode.i_block[i];
|
---|
| 763 | return 0;
|
---|
| 764 | }
|
---|
| 765 |
|
---|
| 766 | errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino)
|
---|
| 767 | {
|
---|
| 768 | struct ext2_inode inode;
|
---|
| 769 | errcode_t retval;
|
---|
| 770 |
|
---|
| 771 | EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
---|
| 772 |
|
---|
| 773 | if (ino > fs->super->s_inodes_count)
|
---|
| 774 | return EXT2_ET_BAD_INODE_NUM;
|
---|
| 775 |
|
---|
| 776 | if (fs->check_directory) {
|
---|
| 777 | retval = (fs->check_directory)(fs, ino);
|
---|
| 778 | if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
|
---|
| 779 | return retval;
|
---|
| 780 | }
|
---|
| 781 | retval = ext2fs_read_inode(fs, ino, &inode);
|
---|
| 782 | if (retval)
|
---|
| 783 | return retval;
|
---|
| 784 | if (!LINUX_S_ISDIR(inode.i_mode))
|
---|
| 785 | return EXT2_ET_NO_DIRECTORY;
|
---|
| 786 | return 0;
|
---|
| 787 | }
|
---|
| 788 |
|
---|