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
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431 | /*
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432 | * XXX test Need check for used inode somehow.
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433 | * (Note: this is hard.)
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434 | */
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435 | if (is_empty_scan(scan))
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436 | goto force_new_group;
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437 | #endif
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438 | }
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439 |
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440 | retval = 0;
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441 | if (extra_bytes) {
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442 | memcpy(scan->temp_buffer+extra_bytes, scan->ptr,
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443 | scan->inode_size - extra_bytes);
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444 | scan->ptr += scan->inode_size - extra_bytes;
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445 | scan->bytes_left -= scan->inode_size - extra_bytes;
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446 |
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447 | #if BB_BIG_ENDIAN
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448 | if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
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449 | (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
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450 | ext2fs_swap_inode_full(scan->fs,
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451 | (struct ext2_inode_large *) inode,
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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 |
|
---|