Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 1 | \input texinfo @c -*-texinfo-*- |
| 2 | @c %**start of header |
| 3 | @setfilename libext2fs.info |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 4 | @settitle The EXT2FS Library (version 1.08) |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 5 | @synindex tp fn |
| 6 | @comment %**end of header |
| 7 | |
| 8 | @ifinfo |
| 9 | @format |
| 10 | START-INFO-DIR-ENTRY |
| 11 | * libext2fs: (libext2fs.info). The EXT2FS library. |
| 12 | END-INFO-DIR-ENTRY |
| 13 | @end format |
| 14 | @end ifinfo |
| 15 | |
| 16 | @c smallbook |
| 17 | |
| 18 | @iftex |
| 19 | @finalout |
| 20 | @end iftex |
| 21 | |
| 22 | @c Note: the edition number is listed in *three* places; please update |
| 23 | @c all three. Also, update the month and year where appropriate. |
| 24 | |
| 25 | @c ==> Update edition number for settitle and subtitle, and in the |
| 26 | @c ==> following paragraph; update date, too. |
| 27 | |
| 28 | |
| 29 | @ifinfo |
| 30 | This file documents the ext2fs library, a library for manipulating the |
| 31 | ext2 filesystem. |
| 32 | |
| 33 | Copyright (C) 1997 Theodore Ts'o |
| 34 | |
| 35 | Permission is granted to make and distribute verbatim copies of |
| 36 | this manual provided the copyright notice and this permission notice |
| 37 | are preserved on all copies. |
| 38 | |
| 39 | @ignore |
| 40 | Permission is granted to process this file through TeX and print the |
| 41 | results, provided the printed document carries copying permission |
| 42 | notice identical to this one except for the removal of this paragraph |
| 43 | (this paragraph not being relevant to the printed manual). |
| 44 | |
| 45 | @end ignore |
| 46 | Permission is granted to copy and distribute modified versions of this |
| 47 | manual under the conditions for verbatim copying, provided that the entire |
| 48 | resulting derived work is distributed under the terms of a permission |
| 49 | notice identical to this one. |
| 50 | |
| 51 | Permission is granted to copy and distribute translations of this manual |
| 52 | into another language, under the above conditions for modified versions, |
| 53 | except that this permission notice may be stated in a translation approved |
| 54 | by the author. |
| 55 | @end ifinfo |
| 56 | |
| 57 | @setchapternewpage on |
| 58 | @titlepage |
| 59 | @c use the new format for titles |
| 60 | |
| 61 | @title The EXT2FS Library |
| 62 | @subtitle The EXT2FS Library |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 63 | @subtitle Version 1.08 |
| 64 | @subtitle April 1997 |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 65 | |
| 66 | @author by Theodore Ts'o |
| 67 | |
| 68 | @c Include the Distribution inside the titlepage so |
| 69 | @c that headings are turned off. |
| 70 | |
| 71 | @tex |
| 72 | \global\parindent=0pt |
| 73 | \global\parskip=8pt |
| 74 | \global\baselineskip=13pt |
| 75 | @end tex |
| 76 | |
| 77 | @page |
| 78 | @vskip 0pt plus 1filll |
| 79 | Copyright @copyright{} 1997 Theodore Ts'o |
| 80 | |
| 81 | @sp 2 |
| 82 | |
| 83 | Permission is granted to make and distribute verbatim copies of |
| 84 | this manual provided the copyright notice and this permission notice |
| 85 | are preserved on all copies. |
| 86 | |
| 87 | Permission is granted to copy and distribute modified versions of this |
| 88 | manual under the conditions for verbatim copying, provided that the entire |
| 89 | resulting derived work is distributed under the terms of a permission |
| 90 | notice identical to this one. |
| 91 | |
| 92 | Permission is granted to copy and distribute translations of this manual |
| 93 | into another language, under the above conditions for modified versions, |
| 94 | except that this permission notice may be stated in a translation approved |
| 95 | by the Foundation. |
| 96 | @end titlepage |
| 97 | @headings double |
| 98 | |
| 99 | @ifinfo |
| 100 | @node Top, Introduction to the EXT2FS Library, (dir), (dir) |
| 101 | |
| 102 | @top The EXT2FS Library |
| 103 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 104 | This manual documents the EXT2FS Library, version 1.08. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 105 | |
| 106 | @end ifinfo |
| 107 | |
| 108 | @menu |
| 109 | * Introduction to the EXT2FS Library:: |
| 110 | * EXT2FS Library Functions:: |
| 111 | * Concept Index:: |
| 112 | * Function Index:: |
| 113 | @end menu |
| 114 | |
| 115 | @c ---------------------------------------------------------------------- |
| 116 | |
| 117 | @node Introduction to the EXT2FS Library, EXT2FS Library Functions, Top, Top |
| 118 | @comment node-name, next, previous, up |
| 119 | @chapter Introduction to the EXT2FS Library |
| 120 | |
| 121 | The EXT2FS library is designed to allow user-level programs to |
| 122 | manipulate an ext2 filesystem. |
| 123 | |
| 124 | @node EXT2FS Library Functions, Concept Index, Introduction to the EXT2FS Library, Top |
| 125 | @comment node-name, next, previous, up |
| 126 | @chapter EXT2FS Library Functions |
| 127 | |
| 128 | @menu |
| 129 | * Filesystem-level functions:: |
| 130 | * Inode Functions:: |
| 131 | * Directory functions:: |
| 132 | * Bitmap Functions:: |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 133 | * EXT2 data abstractions:: |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 134 | * Byte-swapping functions:: |
| 135 | * Other functions:: |
| 136 | @end menu |
| 137 | |
| 138 | @c ---------------------------------------------------------------------- |
| 139 | |
| 140 | @node Filesystem-level functions, Inode Functions, EXT2FS Library Functions, EXT2FS Library Functions |
| 141 | @comment node-name, next, previous, up |
| 142 | @section Filesystem-level functions |
| 143 | |
| 144 | The following functions operate on a filesystem handle. Most EXT2FS |
| 145 | Library functions require a filesystem handle as their first argument. |
| 146 | There are two functions which create a filesystem handle, |
| 147 | @code{ext2fs_open} and @code{ext2fs_initialize}. |
| 148 | |
| 149 | The filesystem can also be closed using @code{ext2fs_close}, and any |
| 150 | changes to the superblock and group descripts can be written out to disk |
| 151 | using @code{ext2fs_flush}. |
| 152 | |
| 153 | @menu |
| 154 | * Opening an ext2 filesystem:: |
| 155 | * Closing and flushing out changes:: |
| 156 | * Initializing a filesystem:: |
| 157 | * Filesystem flag functions:: |
| 158 | @end menu |
| 159 | |
| 160 | @c ---------------------------------------------------------------------- |
| 161 | |
| 162 | @node Opening an ext2 filesystem, Closing and flushing out changes, Filesystem-level functions, Filesystem-level functions |
| 163 | @comment node-name, next, previous, up |
| 164 | @subsection Opening an ext2 filesystem |
| 165 | |
| 166 | Most libext2fs functions take a filesystem handle of type |
| 167 | @code{ext2_filsys}. A filesystem handle is created either by opening |
| 168 | an existing function using @code{ext2fs_open}, or by initializing a new |
| 169 | filesystem using @code{ext2fs_initialize}. |
| 170 | |
| 171 | @deftypefun errcode_t ext2fs_open (const char *@var{name}, int @var{flags}, int @var{superblock}, int @var{block_size}, io_manager @var{manager}, ext2_filsys *@var{ret_fs}) |
| 172 | |
| 173 | Opens a filesystem named @var{name}, using the the io_manager |
| 174 | @var{manager} to define the input/output routines needed to read and |
| 175 | write the filesystem. In the case of the @code{unix_io} io_manager, |
| 176 | @var{name} is interpreted as the Unix filename of the filesystem image. |
| 177 | This is often a device file, such as @file{/dev/hda1}. |
| 178 | |
| 179 | The @var{superblock} parameter specifies the block number of the |
| 180 | superblock which should be used when opening the filesystem. |
| 181 | If @var{superblock} is zero, @code{ext2fs_open} will use the primary |
| 182 | superblock located at offset 1024 bytes from the start of the filesystem |
| 183 | image. |
| 184 | |
| 185 | The @var{block_size} parameter specifies the block size used by the |
| 186 | filesystem. Normally this is determined automatically from the |
| 187 | filesystem uperblock. If @var{block_size} is non-zero, it must match |
| 188 | the block size found in the superblock, or the error |
| 189 | @code{EXT2_ET_UNEXPECTED_BLOCK_SIZE} will be returned. The |
| 190 | @var{block_size} parameter is also used to help fund the superblock when |
| 191 | @var{superblock} is non-zero. |
| 192 | |
| 193 | The @var{flags} argument contains a bitmask of flags which control how |
| 194 | the filesystem open should be handled. |
| 195 | |
| 196 | @table @code |
| 197 | @item EXT2_FLAG_RW |
| 198 | Open the filesystem for reading and writing. Without this flag, the |
| 199 | filesystem is opened for reading only. |
| 200 | |
| 201 | @item EXT2_FLAG_FORCE |
| 202 | Open the filesystem regardless of the feature sets listed in the |
| 203 | superblock. |
| 204 | |
| 205 | @end table |
| 206 | @end deftypefun |
| 207 | |
| 208 | @c ---------------------------------------------------------------------- |
| 209 | |
| 210 | @node Closing and flushing out changes, Initializing a filesystem, Opening an ext2 filesystem, Filesystem-level functions |
| 211 | @comment node-name, next, previous, up |
| 212 | @subsection Closing and flushing out changes |
| 213 | |
| 214 | @deftypefun errcode_t ext2fs_flush (ext2_filsys @var{fs}) |
| 215 | |
| 216 | Write any changes to the high-level filesystem data structures in the |
| 217 | @var{fs} filesystem. The following data structures will be written out: |
| 218 | |
| 219 | @itemize @bullet |
| 220 | @item The filesystem superblock |
| 221 | @item The filesystem group descriptors |
| 222 | @item The filesystem bitmaps, if read in via @code{ext2fs_read_bitmaps}. |
| 223 | @end itemize |
| 224 | |
| 225 | @end deftypefun |
| 226 | |
| 227 | @deftypefun void ext2fs_free (ext2_filsys @var{fs}) |
| 228 | |
| 229 | Close the io_manager abstraction for @var{fs} and release all memory |
| 230 | associated with the filesystem handle. |
| 231 | @end deftypefun |
| 232 | |
| 233 | @deftypefun errcode_t ext2fs_close (ext2_filsys @var{fs}) |
| 234 | |
| 235 | Flush out any changes to the high-level filesystem data structures using |
| 236 | @code{ext2fs_flush} if the filesystem is marked dirty; then close and |
| 237 | free the filesystem using @code{ext2fs_free}. |
| 238 | |
| 239 | @end deftypefun |
| 240 | |
| 241 | @c ---------------------------------------------------------------------- |
| 242 | |
| 243 | @node Initializing a filesystem, Filesystem flag functions, Closing and flushing out changes, Filesystem-level functions |
| 244 | @comment node-name, next, previous, up |
| 245 | @subsection Initializing a filesystem |
| 246 | |
| 247 | An ext2 filesystem is initializing by the @code{mke2fs} program. The |
| 248 | two functions described here, @code{ext2fs_initialize} and |
| 249 | @code{ext2fs_allocate_tables} do much of the initial work for setting up |
| 250 | a filesystem. However, they don't do the whole job. @code{mke2fs} |
| 251 | calls @code{ext2fs_initialize} to set up the filesystem superblock, and |
| 252 | calls @code{ext2fs_allocate_tables} to allocate space for the inode |
| 253 | table, and the inode and block bitmaps. In addition, @code{mke2fs} must |
| 254 | also initialize the inode tables by clearing them with zeros, create the |
| 255 | root and lost+found directories, and reserve the reserved inodes. |
| 256 | |
| 257 | @deftypefun errcode_t ext2fs_initialize (const char *@var{name}, int @var{flags}, struct ext2_super_block *@var{param}, io_manager @var{manager}, ext2_filsys *@var{ret_fs}) |
| 258 | |
| 259 | This function is used by the @code{mke2fs} program to initialize a |
| 260 | filesystem. The @code{ext2fs_initialize} function creates a filesystem |
| 261 | handle which is returned in @var{ret_fs} that has been properly setup |
| 262 | for a filesystem to be located in @var{name}, using the io_manager |
| 263 | @var{manager}. The prototype superblock in @var{param} is used to |
| 264 | supply parameters such as the number of blocks in the filesystem, the |
| 265 | block size, etc. |
| 266 | |
| 267 | The @code{ext2fs_initialize} function does not actually do any I/O; that |
| 268 | will be done when the application program calls @code{ext2fs_close} or |
| 269 | @code{ext2fs_flush}. Also, this function only initializes the |
| 270 | superblock and group descriptor structures. It does not create the |
| 271 | inode table or the root directory. This must be done by the calling |
| 272 | application, such as @code{mke2fs}. |
| 273 | |
| 274 | The following values may be set in the @var{param} prototype superblock; |
| 275 | if a value of 0 is found in a field, @code{ext2fs_initialize} will use a |
| 276 | default value. The calling application should zero out the prototype |
| 277 | entire superblock, and then fill in any appropriate values. |
| 278 | |
| 279 | @table @code |
| 280 | |
| 281 | @item s_blocks_count |
| 282 | The number of blocks in the filesystem. This parameter is mandatory and |
| 283 | must be set by the calling application. |
| 284 | |
| 285 | @item s_inodes_count |
| 286 | The number of inodes in the filesystem. The |
| 287 | default value is determined by calculating the size of the filesystem, |
| 288 | and creating one inode for every 4096 bytes. |
| 289 | |
| 290 | @item s_r_blocks_count |
| 291 | The number of blocks which should be reserved for the superuser. The |
| 292 | default value is zero blocks. |
| 293 | |
| 294 | @item s_log_block_size |
| 295 | The blocksize of the filesystem. Valid values are 0 (1024 bytes), 1 |
| 296 | (2048 bytes), or 2 (4096 bytes). The default blocksize is 1024 bytes. |
| 297 | |
| 298 | @item s_log_frag_size |
| 299 | The size of fragments. The ext2 filesystem does not support fragments |
| 300 | (and may never support fragments). Currently this field must be the |
| 301 | same as @code{s_log_block_size}. |
| 302 | |
| 303 | @item s_first_data_block |
| 304 | The first data block for the filesystem. For filesystem with a |
| 305 | blocksize of 1024 bytes, this value must be at least 1, since the |
| 306 | superblock is located in block number 1. For filesystems with larger |
| 307 | blocksizes, the superblock is still located at an offset of 1024 bytes, |
| 308 | so the superblock is located in block number 0. By default, this value |
| 309 | is set to 1 for filesystems with a block size of 1024 bytes, or 0 for |
| 310 | filesystems with larger blocksizes. |
| 311 | |
| 312 | @item s_max_mnt_count |
| 313 | This field defines the number of times that the filesystem can be |
| 314 | mounted before it should be checked using @code{e2fsck}. When |
| 315 | @code{e2fsck} is run without the @samp{-f} option, @code{e2fsck} will |
| 316 | skip the filesystem check if the number of times that the filesystem has |
| 317 | been mounted is less than @code{s_max_mnt_count} and if the interval |
| 318 | between the last time a filesystem check was performed and the current |
| 319 | time is less than @code{s_checkinterval} (see below). The default value |
| 320 | of @code{s_max_mnt_count} is 20. |
| 321 | |
| 322 | @item s_checkinterval |
| 323 | This field defines the minimal interval between filesystem checks. See |
| 324 | the previous entry for a discussion of how this field is used by |
| 325 | @code{e2fsck}. The default value of this field is 180 days (six |
| 326 | months). |
| 327 | |
| 328 | @item s_errors |
| 329 | This field defines the behavior which should be used by the kernel of |
| 330 | errors are detected in the filesystem. Possible values include: |
| 331 | |
| 332 | @table @samp |
| 333 | @item EXT2_ERRORS_CONTINUE |
| 334 | Continue execution when errors are detected. |
| 335 | |
| 336 | @item EXT2_ERRORS_RO |
| 337 | Remount the filesystem read-only. |
| 338 | |
| 339 | @item EXT2_ERRORS_PANIC |
| 340 | Panic. |
| 341 | |
| 342 | @end table |
| 343 | |
| 344 | The default behavior is @samp{EXT2_ERRORS_CONTINUE}. |
| 345 | |
| 346 | @end table |
| 347 | |
| 348 | @end deftypefun |
| 349 | |
| 350 | @deftypefun errcode_t ext2fs_allocate_tables (ext2_filsys @var{fs}) |
| 351 | Allocate space for the inode table and the block and inode bitmaps. The |
| 352 | inode tables and block and inode bitmaps aren't actually initialized; |
| 353 | this function just allocates the space for them. |
| 354 | @end deftypefun |
| 355 | |
| 356 | @c ---------------------------------------------------------------------- |
| 357 | |
| 358 | @node Filesystem flag functions, , Initializing a filesystem, Filesystem-level functions |
| 359 | @comment node-name, next, previous, up |
| 360 | @subsection Filesystem flag functions |
| 361 | |
| 362 | The filesystem handle has a number of flags which can be manipulated |
| 363 | using the following function. Some of these flags affect how the |
| 364 | libext2fs filesystem behaves; others are provided solely for the |
| 365 | application's convenience. |
| 366 | |
| 367 | @deftypefun void ext2fs_mark_changed (ext2_filsys @var{fs}) |
| 368 | @deftypefunx int ext2fs_test_changed (ext2_filsys @var{fs}) |
| 369 | This flag indicates whether or not the filesystem has been changed. |
| 370 | It is not used by the ext2fs library. |
| 371 | @end deftypefun |
| 372 | |
| 373 | @deftypefun void ext2fs_mark_super_dirty (ext2_filsys @var{fs}) |
| 374 | Mark the filesystem @var{fs} as being dirty; this will cause |
| 375 | the superblock information to be flushed out when @code{ext2fs_close} is |
| 376 | called. @code{ext2fs_mark_super_dirty} will also set the filesystem |
| 377 | changed flag. The dirty flag is automatically cleared by |
| 378 | @code{ext2fs_flush} when the superblock is written to disk. |
| 379 | @end deftypefun |
| 380 | |
| 381 | @deftypefun void ext2fs_mark_valid (ext2_filsys @var{fs}) |
| 382 | @deftypefunx void ext2fs_unmark_valid (ext2_filsys @var{fs}) |
| 383 | @deftypefunx int ext2fs_test_valid (ext2_filsys @var{fs}) |
| 384 | This flag indicates whether or not the filesystem is free of errors. |
| 385 | It is not used by libext2fs, and is solely for the application's |
| 386 | convenience. |
| 387 | @end deftypefun |
| 388 | |
| 389 | @deftypefun void ext2fs_mark_ib_dirty (ext2_filsys @var{fs}) |
| 390 | @deftypefunx void ext2fs_mark_bb_dirty (ext2_filsys @var{fs}) |
| 391 | @deftypefunx int ext2fs_test_ib_dirty (ext2_filsys @var{fs}) |
| 392 | @deftypefunx int ext2fs_test_bb_dirty (ext2_filsys @var{fs}) |
| 393 | These flags indicate whether or not the inode or block bitmaps have been |
| 394 | modified. If the flag is set, it will cause the appropriate bitmap |
| 395 | to be written when the filesystem is closed or flushed. |
| 396 | @end deftypefun |
| 397 | |
| 398 | |
| 399 | |
| 400 | @c ---------------------------------------------------------------------- |
| 401 | |
| 402 | @node Inode Functions, Directory functions, Filesystem-level functions, EXT2FS Library Functions |
| 403 | @comment node-name, next, previous, up |
| 404 | @section Inode Functions |
| 405 | |
| 406 | @menu |
| 407 | * Reading and writing inodes:: |
| 408 | * Iterating over inodes in a filesystem:: |
| 409 | * Iterating over blocks in an inode:: |
| 410 | * Inode Convenience Functions:: |
| 411 | @end menu |
| 412 | |
| 413 | @c ---------------------------------------------------------------------- |
| 414 | |
| 415 | @node Reading and writing inodes, Iterating over inodes in a filesystem, Inode Functions, Inode Functions |
| 416 | @comment node-name, next, previous, up |
| 417 | @subsection Reading and writing inodes |
| 418 | |
| 419 | @deftypefun errcode_t ext2fs_read_inode (ext2_filsys @var{fs}, ino_t @var{ino}, struct ext2_inode *@var{inode}) |
| 420 | Read the inode number @var{ino} into @var{inode}. |
| 421 | @end deftypefun |
| 422 | |
| 423 | @deftypefun errcode_t ext2fs_write_inode(ext2_filsys @var{fs}, ino_t @var{ino}, struct ext2_inode *@var{inode}) |
| 424 | Write @var{inode} to inode @var{ino}. |
| 425 | @end deftypefun |
| 426 | |
| 427 | |
| 428 | @c ---------------------------------------------------------------------- |
| 429 | |
| 430 | @node Iterating over inodes in a filesystem, Iterating over blocks in an inode, Reading and writing inodes, Inode Functions |
| 431 | @comment node-name, next, previous, up |
| 432 | @subsection Iterating over inodes in a filesystem |
| 433 | |
| 434 | The inode_scan abstraction is useful for iterating over all the inodes |
| 435 | in a filesystem. |
| 436 | |
| 437 | @deftypefun errcode_t ext2fs_open_inode_scan (ext2_filsys @var{fs}, int @var{buffer_blocks}, ext2_inode_scan *@var{scan}) |
| 438 | Initialize the iteration variable @var{scan}. This variable is used by |
| 439 | @code{ext2fs_get_next_inode}. The @var{buffer_blocks} parameter |
| 440 | controls how many blocks of the inode table are read in at a time. A |
| 441 | large number of blocks requires more memory, but reduces the overhead in |
| 442 | seeking and reading from the disk. If @var{buffer_blocks} is zero, a |
| 443 | suitable default value will be used. |
| 444 | @end deftypefun |
| 445 | |
| 446 | @deftypefun void ext2fs_close_inode_scan (ext2_inode_scan @var{scan}) |
| 447 | Release the memory associated with @var{scan} and invalidate it. |
| 448 | @end deftypefun |
| 449 | |
| 450 | @deftypefun errcode_t ext2fs_get_next_inode (ext2_inode_scan @var{scan}, ino_t *@var{ino}, struct ext2_inode *@var{inode}) |
| 451 | |
| 452 | This function returns the next inode from the filesystem; the inode |
| 453 | number of the inode is stored in @var{ino}, and the inode is stored in |
| 454 | @var{inode}. |
| 455 | |
| 456 | If the inode is located in a block that has been marked as bad, |
| 457 | @code{ext2fs_get_next_inode} will return the error |
| 458 | @code{EXT2_ET_BAD_BLOCK_IN_INODE_TABLE}. |
| 459 | @end deftypefun |
| 460 | |
| 461 | @deftypefun errcode_t ext2fs_inode_scan_goto_blockgroup (ext2_inode_scan @var{scan}, int @var{group}) |
| 462 | Start the inode scan at a particular ext2 blockgroup, @var{group}. |
| 463 | This function may be safely called at any time while @var{scan} is valid. |
| 464 | @end deftypefun |
| 465 | |
| 466 | @deftypefun void ext2fs_set_inode_callback (ext2_inode_scan @var{scan}, errcode_t (*done_group)(ext2_filsys @var{fs}, ext2_inode_scan @var{scan}, dgrp_t @var{group}, void * @var{private}), void *@var{done_group_data}) |
| 467 | Register a callback function which will be called by |
| 468 | @code{ext2_get_next_inode} when all of the inodes in a block group have |
| 469 | been processed. |
| 470 | @end deftypefun |
| 471 | |
| 472 | @deftypefun int ext2fs_inode_scan_flags (ext2_inode_scan @var{scan}, int @var{set_flags}, int @var{clear_flags}) |
| 473 | |
| 474 | Set the scan_flags @var{set_flags} and clear the scan_flags @var{clear_flags}. |
| 475 | The following flags can be set using this interface: |
| 476 | |
| 477 | @table @samp |
| 478 | |
| 479 | @item EXT2_SF_SKIP_MISSING_ITABLE |
| 480 | When a block group is missing an inode table, skip it. If this flag is |
| 481 | not set @code{ext2fs_get_next_inode} will return the error |
| 482 | EXT2_ET_MISSING_INODE_TABLE. |
| 483 | |
| 484 | @end table |
| 485 | |
| 486 | @end deftypefun |
| 487 | |
| 488 | @c ---------------------------------------------------------------------- |
| 489 | |
| 490 | @node Iterating over blocks in an inode, Inode Convenience Functions, Iterating over inodes in a filesystem, Inode Functions |
| 491 | @comment node-name, next, previous, up |
| 492 | @subsection Iterating over blocks in an inode |
| 493 | |
| 494 | @deftypefun errcode_t ext2fs_block_iterate (ext2_filsys @var{fs}, ino_t @var{ino}, int @var{flags}, char *block_buf, int (*func)(ext2_filsys @var{fs}, blk_t *@var{blocknr}, int @var{blockcnt}, void *@var{private}), void *@var{private}) |
| 495 | @end deftypefun |
| 496 | |
| 497 | @deftypefun errcode_t ext2fs_block_iterate2 (ext2_filsys @var{fs}, ino_t @var{ino}, int @var{flags}, char *@var{block}_buf, int (*func)(ext2_filsys @var{fs}, blk_t *@var{blocknr}, int @var{blockcnt}, blk_t @var{ref_blk}, int @var{ref_offset}, void *@var{private}), void *@var{private}) |
| 498 | @end deftypefun |
| 499 | |
| 500 | @c ---------------------------------------------------------------------- |
| 501 | |
| 502 | @node Inode Convenience Functions, , Iterating over blocks in an inode, Inode Functions |
| 503 | @comment node-name, next, previous, up |
| 504 | @subsection Convenience functions for Inodes |
| 505 | |
| 506 | @deftypefun errcode_t ext2fs_get_blocks (ext2_filsys @var{fs}, ino_t @var{ino}, blk_t *@var{blocks}) |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 507 | |
| 508 | Returns an array of blocks corresponding to the direct, |
| 509 | indirect, doubly indirect, and triply indirect blocks as stored in the |
| 510 | inode structure. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 511 | @end deftypefun |
| 512 | |
| 513 | @deftypefun errcode_t ext2fs_check_directory (ext2_filsys @var{fs}, ino_t @var{ino}) |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 514 | Returns 0 if @var{ino} is a directory, and @code{ENOTDIR} if it is not. |
| 515 | @end deftypefun |
| 516 | |
| 517 | @deftypefun int ext2_inode_has_valid_blocks (struct ext2_inode *@var{inode}) |
| 518 | |
| 519 | Returns 1 if the inode's block entries actually valid block entries, and |
| 520 | 0 if not. Inodes which represent devices and fast symbolic links do not |
| 521 | contain valid block entries. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 522 | @end deftypefun |
| 523 | |
| 524 | @c ---------------------------------------------------------------------- |
| 525 | |
| 526 | @node Directory functions, Bitmap Functions, Inode Functions, EXT2FS Library Functions |
| 527 | @comment node-name, next, previous, up |
| 528 | @section Directory functions |
| 529 | |
| 530 | @menu |
| 531 | * Directory block functions:: |
| 532 | * Iterating over a directory:: |
| 533 | * Creating and expanding directories:: |
| 534 | * Creating and removing directory entries:: |
| 535 | * Looking up filenames:: |
| 536 | * Translating inode numbers to filenames:: |
| 537 | @end menu |
| 538 | |
| 539 | @c ---------------------------------------------------------------------- |
| 540 | |
| 541 | @node Directory block functions, Iterating over a directory, Directory functions, Directory functions |
| 542 | @comment node-name, next, previous, up |
| 543 | @subsection Directory block functions |
| 544 | |
| 545 | @deftypefun errcode_t ext2fs_read_dir_block (ext2_filsys @var{fs}, blk_t @var{block}, void *@var{buf}) |
| 546 | @end deftypefun |
| 547 | |
| 548 | @deftypefun errcode_t ext2fs_write_dir_block (ext2_filsys @var{fs}, blk_t @var{block}, void *@var{buf}) |
| 549 | @end deftypefun |
| 550 | |
| 551 | @deftypefun errcode_t ext2fs_new_dir_block (ext2_filsys @var{fs}, ino_t @var{dir}_ino, ino_t @var{parent_ino}, char **@var{block}) |
| 552 | @end deftypefun |
| 553 | |
| 554 | @c ---------------------------------------------------------------------- |
| 555 | |
| 556 | @node Iterating over a directory, Creating and expanding directories, Directory block functions, Directory functions |
| 557 | @comment node-name, next, previous, up |
| 558 | @subsection Iterating over a directory |
| 559 | |
| 560 | @deftypefun errcode_t ext2fs_dir_iterate (ext2_filsys @var{fs}, ino_t @var{dir}, int @var{flags}, char *@var{block_buf}, int (*@var{func})(struct ext2_dir_entry *@var{dirent}, int @var{offset}, int @var{blocksize}, char *@var{buf}, void *@var{private}), void *@var{private}) |
| 561 | @end deftypefun |
| 562 | |
| 563 | @c ---------------------------------------------------------------------- |
| 564 | |
| 565 | @node Creating and expanding directories, Creating and removing directory entries, Iterating over a directory, Directory functions |
| 566 | @comment node-name, next, previous, up |
| 567 | @subsection Creating and expanding directories |
| 568 | |
| 569 | @deftypefun errcode_t ext2fs_mkdir (ext2_filsys @var{fs}, ino_t @var{parent}, ino_t @var{inum}, const char *@var{name}) |
| 570 | @end deftypefun |
| 571 | |
| 572 | @deftypefun errcode_t ext2fs_expand_dir (ext2_filsys @var{fs}, ino_t @var{dir}) |
| 573 | @end deftypefun |
| 574 | |
| 575 | @c ---------------------------------------------------------------------- |
| 576 | |
| 577 | @node Creating and removing directory entries, Looking up filenames, Creating and expanding directories, Directory functions |
| 578 | @comment node-name, next, previous, up |
| 579 | @subsection Creating and removing directory entries |
| 580 | |
| 581 | @deftypefun errcode_t ext2fs_link (ext2_filsys @var{fs}, ino_t @var{dir}, const char *@var{name}, ino_t @var{ino}, int flags) |
| 582 | @end deftypefun |
| 583 | |
| 584 | @deftypefun errcode_t ext2fs_unlink (ext2_filsys @var{fs}, ino_t @var{dir}, const char *@var{name}, ino_t @var{ino}, int @var{flags}) |
| 585 | @end deftypefun |
| 586 | |
| 587 | @c ---------------------------------------------------------------------- |
| 588 | |
| 589 | @node Looking up filenames, Translating inode numbers to filenames, Creating and removing directory entries, Directory functions |
| 590 | @comment node-name, next, previous, up |
| 591 | @subsection Looking up filenames |
| 592 | |
| 593 | @deftypefun errcode_t ext2fs_lookup (ext2_filsys @var{fs}, ino_t @var{dir}, const char *@var{name}, int @var{namelen}, char *@var{buf}, ino_t *@var{inode}) |
| 594 | @end deftypefun |
| 595 | |
| 596 | @deftypefun errcode_t ext2fs_namei (ext2_filsys @var{fs}, ino_t @var{root}, ino_t @var{cwd}, const char *@var{name}, ino_t *@var{inode}) |
| 597 | @end deftypefun |
| 598 | |
| 599 | @deftypefun errcode_t ext2fs_namei_follow (ext2_filsys @var{fs}, ino_t @var{root}, ino_t @var{cwd}, const char *@var{name}, ino_t *@var{inode}) |
| 600 | @end deftypefun |
| 601 | |
| 602 | @deftypefun errcode_t ext2fs_follow_link (ext2_filsys @var{fs}, ino_t @var{root}, ino_t @var{cwd}, ino_t @var{inode}, ino_t *@var{res}_inode) |
| 603 | @end deftypefun |
| 604 | |
| 605 | @c ---------------------------------------------------------------------- |
| 606 | |
| 607 | @node Translating inode numbers to filenames, , Looking up filenames, Directory functions |
| 608 | @comment node-name, next, previous, up |
| 609 | @subsection Translating inode numbers to filenames |
| 610 | |
| 611 | @deftypefun errcode_t ext2fs_get_pathname (ext2_filsys @var{fs}, ino_t @var{dir}, ino_t @var{ino}, char **@var{name}) |
| 612 | @end deftypefun |
| 613 | |
| 614 | |
| 615 | @c ---------------------------------------------------------------------- |
| 616 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 617 | @node Bitmap Functions, EXT2 data abstractions, Directory functions, EXT2FS Library Functions |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 618 | @comment node-name, next, previous, up |
| 619 | @section Bitmap Functions |
| 620 | |
| 621 | @menu |
| 622 | * Reading and Writing Bitmaps:: |
| 623 | * Allocating Bitmaps:: |
| 624 | * Free bitmaps:: |
| 625 | * Bitmap Operations:: |
| 626 | * Comparing bitmaps:: |
| 627 | * Modifying Bitmaps:: |
| 628 | * Resizing Bitmaps:: |
| 629 | * Clearing Bitmaps:: |
| 630 | @end menu |
| 631 | |
| 632 | @c ---------------------------------------------------------------------- |
| 633 | |
| 634 | @node Reading and Writing Bitmaps, Allocating Bitmaps, Bitmap Functions, Bitmap Functions |
| 635 | @comment node-name, next, previous, up |
| 636 | @subsection Reading and Writing Bitmaps |
| 637 | |
| 638 | @deftypefun errcode_t ext2fs_write_inode_bitmap (ext2_filsys @var{fs}) |
| 639 | @end deftypefun |
| 640 | |
| 641 | @deftypefun errcode_t ext2fs_write_block_bitmap (ext2_filsys @var{fs}) |
| 642 | @end deftypefun |
| 643 | |
| 644 | @deftypefun errcode_t ext2fs_read_inode_bitmap (ext2_filsys @var{fs}) |
| 645 | @end deftypefun |
| 646 | |
| 647 | @deftypefun errcode_t ext2fs_read_block_bitmap (ext2_filsys @var{fs}) |
| 648 | @end deftypefun |
| 649 | |
| 650 | @deftypefun errcode_t ext2fs_read_bitmaps (ext2_filsys @var{fs}) |
| 651 | @end deftypefun |
| 652 | |
| 653 | @deftypefun errcode_t ext2fs_write_bitmaps (ext2_filsys @var{fs}) |
| 654 | @end deftypefun |
| 655 | |
| 656 | @c ---------------------------------------------------------------------- |
| 657 | |
| 658 | @node Allocating Bitmaps, Free bitmaps, Reading and Writing Bitmaps, Bitmap Functions |
| 659 | @comment node-name, next, previous, up |
| 660 | @subsection Allocating Bitmaps |
| 661 | |
| 662 | @deftypefun errcode_t ext2fs_allocate_generic_bitmap (__u32 @var{start}, __u32 @var{end}, _u32 @var{real_end}, const char *@var{descr}, ext2fs_generic_bitmap *@var{ret}) |
| 663 | @end deftypefun |
| 664 | |
| 665 | @deftypefun errcode_t ext2fs_allocate_block_bitmap (ext2_filsys @var{fs}, const char *@var{descr}, ext2fs_block_bitmap *@var{ret}) |
| 666 | @end deftypefun |
| 667 | |
| 668 | @deftypefun errcode_t ext2fs_allocate_inode_bitmap (ext2_filsys @var{fs}, const char *@var{descr}, ext2fs_inode_bitmap *@var{ret}) |
| 669 | @end deftypefun |
| 670 | |
| 671 | @c ---------------------------------------------------------------------- |
| 672 | |
| 673 | @node Free bitmaps, Bitmap Operations, Allocating Bitmaps, Bitmap Functions |
| 674 | @comment node-name, next, previous, up |
| 675 | @subsection Freeing bitmaps |
| 676 | |
| 677 | |
| 678 | @deftypefun void ext2fs_free_generic_bitmap (ext2fs_inode_bitmap @var{bitmap}) |
| 679 | @end deftypefun |
| 680 | |
| 681 | @deftypefun void ext2fs_free_block_bitmap (ext2fs_block_bitmap @var{bitmap}) |
| 682 | @end deftypefun |
| 683 | |
| 684 | @deftypefun void ext2fs_free_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}) |
| 685 | @end deftypefun |
| 686 | |
| 687 | |
| 688 | @c ---------------------------------------------------------------------- |
| 689 | |
| 690 | @node Bitmap Operations, Comparing bitmaps, Free bitmaps, Bitmap Functions |
| 691 | @comment node-name, next, previous, up |
| 692 | @subsection Bitmap Operations |
| 693 | |
| 694 | @deftypefun void ext2fs_mark_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 695 | |
| 696 | @deftypefunx void ext2fs_unmark_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 697 | |
| 698 | @deftypefunx int ext2fs_test_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 699 | |
| 700 | These functions set, clear, and test bits in a block bitmap @var{bitmap}. |
| 701 | @end deftypefun |
| 702 | |
| 703 | |
| 704 | @deftypefun void ext2fs_mark_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 705 | |
| 706 | @deftypefunx void ext2fs_unmark_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 707 | |
| 708 | @deftypefunx int ext2fs_test_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 709 | |
| 710 | These functions set, clear, and test bits in an inode bitmap @var{bitmap}. |
| 711 | @end deftypefun |
| 712 | |
| 713 | @deftypefun void ext2fs_fast_mark_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 714 | |
| 715 | @deftypefunx void ext2fs_fast_unmark_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 716 | |
| 717 | @deftypefunx int ext2fs_fast_test_block_bitmap (ext2fs_block_bitmap @var{bitmap}, blk_t @var{block}) |
| 718 | |
| 719 | @deftypefunx void ext2fs_fast_mark_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 720 | |
| 721 | @deftypefunx void ext2fs_fast_unmark_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 722 | |
| 723 | @deftypefunx int ext2fs_fast_test_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{inode}) |
| 724 | |
| 725 | These ``fast'' functions are like their normal counterparts; however, |
| 726 | they are implemented as inline functions and do not perform bounds |
| 727 | checks on the inode number or block number; they are assumed to be |
| 728 | correct. They should only be used in speed-critical applications, where |
| 729 | the inode or block number has already been validated by other means. |
| 730 | @end deftypefun |
| 731 | |
| 732 | @deftypefun blk_t ext2fs_get_block_bitmap_start (ext2fs_block_bitmap @var{bitmap}) |
| 733 | @deftypefunx ino_t ext2fs_get_inode_bitmap_start (ext2fs_inode_bitmap @var{bitmap}) |
| 734 | Return the first inode or block which is stored in the bitmap. |
| 735 | @end deftypefun |
| 736 | |
| 737 | @deftypefun blk_t ext2fs_get_block_bitmap_end (ext2fs_block_bitmap @var{bitmap}) |
| 738 | @deftypefunx ino_t ext2fs_get_inode_bitmap_end (ext2fs_inode_bitmap @var{bitmap}) |
| 739 | |
| 740 | Return the first inode or block which is stored in the bitmap. |
| 741 | @end deftypefun |
| 742 | |
| 743 | |
| 744 | @c ---------------------------------------------------------------------- |
| 745 | |
| 746 | @node Comparing bitmaps, Modifying Bitmaps, Bitmap Operations, Bitmap Functions |
| 747 | @comment node-name, next, previous, up |
| 748 | @subsection Comparing bitmaps |
| 749 | |
| 750 | @deftypefun errcode_t ext2fs_compare_block_bitmap (ext2fs_block_bitmap @var{bm1}, ext2fs_block_bitmap @var{bm2}) |
| 751 | @end deftypefun |
| 752 | |
| 753 | @deftypefun errcode_t ext2fs_compare_inode_bitmap (ext2fs_inode_bitmap @var{bm1}, ext2fs_inode_bitmap @var{bm2}) |
| 754 | @end deftypefun |
| 755 | |
| 756 | |
| 757 | @c ---------------------------------------------------------------------- |
| 758 | |
| 759 | @node Modifying Bitmaps, Resizing Bitmaps, Comparing bitmaps, Bitmap Functions |
| 760 | @comment node-name, next, previous, up |
| 761 | @subsection Modifying Bitmaps |
| 762 | |
| 763 | @deftypefun errcode_t ext2fs_fudge_inode_bitmap_end (ext2fs_inode_bitmap @var{bitmap}, ino_t @var{end}, ino_t *@var{oend}) |
| 764 | @end deftypefun |
| 765 | |
| 766 | @deftypefun errcode_t ext2fs_fudge_block_bitmap_end (ext2fs_block_bitmap @var{bitmap}, blk_t @var{end}, blk_t *@var{oend}) |
| 767 | @end deftypefun |
| 768 | |
| 769 | @c ---------------------------------------------------------------------- |
| 770 | |
| 771 | @node Resizing Bitmaps, Clearing Bitmaps, Modifying Bitmaps, Bitmap Functions |
| 772 | @comment node-name, next, previous, up |
| 773 | @subsection Resizing Bitmaps |
| 774 | |
| 775 | @deftypefun errcode_t ext2fs_resize_generic_bitmap (__u32 @var{new_end}, __u32 @var{new_real_end}, ext2fs_generic_bitmap @var{bmap}) |
| 776 | @end deftypefun |
| 777 | |
| 778 | @deftypefun errcode_t ext2fs_resize_inode_bitmap (__u32 @var{new_end}, __u32 @var{new_real_end}, ext2fs_inode_bitmap @var{bmap}) |
| 779 | @end deftypefun |
| 780 | |
| 781 | @deftypefun errcode_t ext2fs_resize_block_bitmap (__u32 @var{new_end}, __u32 @var{new_real_end}, ext2fs_block_bitmap @var{bmap}) |
| 782 | @end deftypefun |
| 783 | |
| 784 | |
| 785 | @c ---------------------------------------------------------------------- |
| 786 | |
| 787 | @node Clearing Bitmaps, , Resizing Bitmaps, Bitmap Functions |
| 788 | @comment node-name, next, previous, up |
| 789 | @subsection Clearing Bitmaps |
| 790 | |
| 791 | @deftypefun void ext2fs_clear_inode_bitmap (ext2fs_inode_bitmap @var{bitmap}) |
| 792 | @end deftypefun |
| 793 | |
| 794 | @deftypefun void ext2fs_clear_block_bitmap (ext2fs_block_bitmap @var{bitmap}) |
| 795 | @end deftypefun |
| 796 | |
| 797 | |
| 798 | @c ---------------------------------------------------------------------- |
| 799 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 800 | @node EXT2 data abstractions, Byte-swapping functions, Bitmap Functions, EXT2FS Library Functions |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 801 | @comment node-name, next, previous, up |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 802 | @section EXT2 data abstractions |
| 803 | |
| 804 | The ext2 library has a number of abstractions which are useful for ext2 |
| 805 | utility programs. |
| 806 | |
| 807 | @menu |
| 808 | * Badblocks list management:: |
| 809 | * Directory-block list management:: |
| 810 | * Inode count functions:: |
| 811 | @end menu |
| 812 | |
| 813 | @c ---------------------------------------------------------------------- |
| 814 | |
| 815 | @node Badblocks list management, Directory-block list management, EXT2 data abstractions, EXT2 data abstractions |
| 816 | @comment node-name, next, previous, up |
| 817 | @subsection Badblocks list management |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 818 | |
| 819 | |
| 820 | @deftypefun errcode_t ext2fs_badblocks_list_create (ext2_badblocks_list *@var{ret}, int @var{size}) |
| 821 | @end deftypefun |
| 822 | |
| 823 | @deftypefun void ext2fs_badblocks_list_free (ext2_badblocks_list @var{bb}) |
| 824 | @end deftypefun |
| 825 | |
| 826 | @deftypefun errcode_t ext2fs_badblocks_list_add (ext2_badblocks_list @var{bb}, blk_t @var{blk}) |
| 827 | @end deftypefun |
| 828 | |
| 829 | @deftypefun int ext2fs_badblocks_list_test (ext2_badblocks_list @var{bb}, blk_t @var{blk}) |
| 830 | @end deftypefun |
| 831 | |
| 832 | @deftypefun errcode_t ext2fs_badblocks_list_iterate_begin (ext2_badblocks_list @var{bb}, ext2_badblocks_iterate *@var{ret}) |
| 833 | @end deftypefun |
| 834 | |
| 835 | @deftypefun int ext2fs_badblocks_list_iterate (ext2_badblocks_iterate iter, blk_t *@var{blk}) |
| 836 | @end deftypefun |
| 837 | |
| 838 | @deftypefun void ext2fs_badblocks_list_iterate_end (ext2_badblocks_iterate @var{iter}) |
| 839 | @end deftypefun |
| 840 | |
| 841 | @deftypefun errcode_t ext2fs_update_bb_inode (ext2_filsys @var{fs}, ext2_badblocks_list @var{bb_list}) |
| 842 | @end deftypefun |
| 843 | |
| 844 | @deftypefun errcode_t ext2fs_read_bb_inode (ext2_filsys @var{fs}, ext2_badblocks_list *@var{bb_list}) |
| 845 | @end deftypefun |
| 846 | |
| 847 | @deftypefun errcode_t ext2fs_read_bb_FILE (ext2_filsys @var{fs}, FILE *f, ext2_badblocks_list *@var{bb_list}, void (*invalid)(ext2_filsys @var{fs}, blk_t @var{blk})) |
| 848 | @end deftypefun |
| 849 | |
| 850 | |
| 851 | @c ---------------------------------------------------------------------- |
| 852 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 853 | @node Directory-block list management, Inode count functions, Badblocks list management, EXT2 data abstractions |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 854 | @comment node-name, next, previous, up |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 855 | @subsection Directory-block list management |
| 856 | |
| 857 | The dblist abstraction stores a list of blocks belonging to |
| 858 | directories. This list can be useful when a program needs to interate |
| 859 | over all directory entries in a filesystem; @code{e2fsck} does this in |
| 860 | pass 2 of its operations, and @code{debugfs} needs to do this when it is |
| 861 | trying to turn an inode number into a pathname. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 862 | |
| 863 | @deftypefun errcode_t ext2fs_init_dblist (ext2_filsys @var{fs}, ext2_dblist *@var{ret_dblist}) |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 864 | |
| 865 | Creates a dblist data structure and return it in @var{ret_dblist}. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 866 | @end deftypefun |
| 867 | |
| 868 | @deftypefun void ext2fs_free_dblist (ext2_dblist @var{dblist}) |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 869 | |
| 870 | Free a dblist data structure. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 871 | @end deftypefun |
| 872 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 873 | @deftypefun errcode_t ext2fs_add_dir_block (ext2_dblist @var{dblist}, ino_t @var{ino}, blk_t @var{blk}, int @var{blockcnt}) |
| 874 | |
| 875 | Add an entry to the dblist data structure. This call records the fact |
| 876 | that block number @var{blockcnt} of directory inode @var{ino} is stored |
| 877 | in block @var{blk}. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 878 | @end deftypefun |
| 879 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 880 | @deftypefun errcode_t ext2fs_set_dir_block (ext2_dblist @var{dblist}, ino_t @var{ino}, blk_t @var{blk}, int @var{blockcnt}) |
| 881 | |
| 882 | Change an entry in the dblist data structure; this changes the location |
| 883 | of block number @var{blockcnt} of directory indoe @var{ino} to be block |
| 884 | @var{blk}. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 885 | @end deftypefun |
| 886 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 887 | @deftypefun errcode_t ext2fs_dblist_iterate (ext2_dblist @var{dblist}, int (*func)(ext2_filsys @var{fs}, struct ext2_db_entry *@var{db_info}, void *@var{private}), void *@var{private}) |
| 888 | |
| 889 | This iterator calls @var{func} for every entry in the dblist data structure. |
| 890 | @end deftypefun |
| 891 | |
| 892 | @deftypefun errcode_t ext2fs_dblist_dir_iterate (ext2_dblist @var{dblist}, int flags, char *@var{block_buf}, int (*func)(ino_t @var{dir}, int @var{entry}, struct ext2_dir_entry *@var{dirent}, int @var{offset}, int @var{blocksize}, char *@var{buf}, void *@var{private}), void *@var{private}) |
| 893 | |
| 894 | This iterator takes reads in the directory block indicated in each |
| 895 | dblist entry, and calls @var{func} for each directory entry in each |
| 896 | directory block. If @var{dblist} contains all the directory blocks in a |
| 897 | filesystem, this function provides a convenient way to iterate over all |
| 898 | directory entries for that filesystem. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 899 | @end deftypefun |
| 900 | |
| 901 | @c ---------------------------------------------------------------------- |
| 902 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 903 | @node Inode count functions, , Directory-block list management, EXT2 data abstractions |
| 904 | @comment node-name, next, previous, up |
| 905 | @subsection Inode count functions |
| 906 | |
| 907 | The icount abstraction is a specialized data type used by @code{e2fsck} |
| 908 | to store how many times a particular inode is referenced by the |
| 909 | filesystem. This is used twice; once to store the actual number of times |
| 910 | that the inode is reference; and once to store the claimed number of times |
| 911 | the inode is referenced according to the inode structure. |
| 912 | |
| 913 | This abstraction is designed to be extremely efficient for storing this |
| 914 | sort of information, by taking advantage of the following properties of |
| 915 | inode counts, namely (1) inode counts are very often zero (because |
| 916 | the inode is currrently not in use), and (2) many files have a inode |
| 917 | count of 1 (because they are a file which has no additional hard links). |
| 918 | |
| 919 | @deftypefun errcode_t ext2fs_create_icount2(ext2_filsys @var{fs}, int @var{flags}, int @var{size}, ext2_icount_t @var{hint}, ext2_icount_t *@var{ret}) |
| 920 | |
| 921 | Creates an icount stucture for a filesystem @var{fs}, with initial space |
| 922 | for @var{size} inodes whose count is greater than 1. The @var{flags} |
| 923 | parameter is either 0 or @code{EXT2_ICOUNT_OPT_INCREMENT}, which |
| 924 | indicates that icount structure should be able to increment inode counts |
| 925 | quickly. The icount structure is returned in @var{ret}. The returned |
| 926 | icount structure initially has a count of zero for all inodes. |
| 927 | |
| 928 | The @var{hint} parameter allows the caller to optionally pass in another |
| 929 | icount structure which is used to initialize the array of inodes whose |
| 930 | count is greater than 1. It is used purely as a speed optimization so |
| 931 | that the icount structure can determine in advance which inodes are |
| 932 | likely to contain a count grater than 1. |
| 933 | @end deftypefun |
| 934 | |
| 935 | @deftypefun void ext2fs_free_icount(ext2_icount_t @var{icount}) |
| 936 | |
| 937 | Frees an icount structure. |
| 938 | @end deftypefun |
| 939 | |
| 940 | @deftypefun errcode_t ext2fs_icount_fetch(ext2_icount_t @var{icount}, ino_t @var{ino}, __u16 *@var{ret}) |
| 941 | |
| 942 | Returns in @var{ret} fetches the count for a particular inode @var{ino}. |
| 943 | @end deftypefun |
| 944 | |
| 945 | @deftypefun errcode_t ext2fs_icount_increment(ext2_icount_t @var{icount}, ino_t @var{ino}, __u16 *@var{ret}) |
| 946 | |
| 947 | Increments the ref count for inode @var{ino}. |
| 948 | @end deftypefun |
| 949 | |
| 950 | @deftypefun errcode_t ext2fs_icount_decrement(ext2_icount_t @var{icount}, ino_t @var{ino}, __u16 *@var{ret}) |
| 951 | |
| 952 | Decrements the ref count for inode @var{ino}. |
| 953 | @end deftypefun |
| 954 | |
| 955 | @deftypefun errcode_t ext2fs_icount_store(ext2_icount_t @var{icount}, ino_t @var{ino}, __u16 @var{count}) |
| 956 | |
| 957 | Sets the reference count for inode @var{ino} to be @var{count}. |
| 958 | @end deftypefun |
| 959 | |
| 960 | @deftypefun ino_t ext2fs_get_icount_size(ext2_icount_t @var{icount}) |
| 961 | |
| 962 | Returns the current number of inodes in @var{icount} which has a count |
| 963 | greater than 1. |
| 964 | @end deftypefun |
| 965 | |
| 966 | @deftypefun errcode_t ext2fs_icount_validate(ext2_icount_t @var{icount}, FILE *@var{f}) |
| 967 | |
| 968 | Validates the internal rep invariant of @var{icount}; if there are any |
| 969 | problems, print out debugging information to @var{f}. This function is |
| 970 | intended for debugging and testing use only. |
| 971 | @end deftypefun |
| 972 | |
| 973 | |
| 974 | @c ---------------------------------------------------------------------- |
| 975 | |
| 976 | @node Byte-swapping functions, Other functions, EXT2 data abstractions, EXT2FS Library Functions |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 977 | @comment node-name, next, previous, up |
| 978 | @section Byte-swapping functions |
| 979 | |
| 980 | @deftypefun void ext2fs_swap_super (struct ext2_super_block * @var{super}) |
| 981 | @end deftypefun |
| 982 | |
| 983 | @deftypefun void ext2fs_swap_group_desc (struct ext2_group_desc *@var{gdp}) |
| 984 | @end deftypefun |
| 985 | |
| 986 | @deftypefun void ext2fs_swap_inode (ext2_filsys @var{fs}, struct ext2_inode *@var{to}, struct ext2_inode *@var{from}, int @var{hostorder}) |
| 987 | @end deftypefun |
| 988 | |
| 989 | @deftypefun int ext2fs_native_flag (void) |
| 990 | @end deftypefun |
| 991 | |
| 992 | |
| 993 | @c ---------------------------------------------------------------------- |
| 994 | |
| 995 | @node Other functions, , Byte-swapping functions, EXT2FS Library Functions |
| 996 | @comment node-name, next, previous, up |
| 997 | @section Other functions |
| 998 | |
| 999 | /* alloc.c */ |
| 1000 | @deftypefun errcode_t ext2fs_new_inode (ext2_filsys @var{fs}, ino_t @var{dir}, int @var{mode}, ext2fs_inode_bitmap @var{map}, ino_t *@var{ret}) |
| 1001 | @end deftypefun |
| 1002 | |
| 1003 | @deftypefun errcode_t ext2fs_new_block (ext2_filsys @var{fs}, blk_t @var{goal}, ext2fs_block_bitmap @var{map}, blk_t *@var{ret}) |
| 1004 | @end deftypefun |
| 1005 | |
| 1006 | @deftypefun errcode_t ext2fs_get_free_blocks (ext2_filsys @var{fs}, blk_t @var{start}, blk_t @var{finish}, int @var{num}, ext2fs_block_bitmap @var{map}, blk_t *@var{ret}) |
| 1007 | @end deftypefun |
| 1008 | |
| 1009 | /* check_desc.c */ |
| 1010 | @deftypefun errcode_t ext2fs_check_desc (ext2_filsys @var{fs}) |
| 1011 | @end deftypefun |
| 1012 | |
| 1013 | @deftypefun errcode_t ext2_get_num_dirs (ext2_filsys @var{fs}, ino_t *@var{ret_num_dirs}) |
| 1014 | @end deftypefun |
| 1015 | |
| 1016 | |
| 1017 | /* getsize.c */ |
| 1018 | @deftypefun errcode_t ext2fs_get_device_size (const char *@var{file}, int @var{blocksize}, blk_t *@var{retblocks}) |
| 1019 | @end deftypefun |
| 1020 | |
| 1021 | |
| 1022 | /* ismounted.c */ |
| 1023 | @deftypefun errcode_t ext2fs_check_if_mounted (const char *@var{file}, int *@var{mount_flags}) |
| 1024 | @end deftypefun |
| 1025 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 1026 | /* version.c */ |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 1027 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 1028 | @deftypefun int ext2fs_get_library_version(const char **@var{ver_string}, const char **@var{date_string}) |
| 1029 | |
| 1030 | This function returns the current version of the ext2 library. The |
| 1031 | return value contains an integer version code, which consists of the |
| 1032 | major version number of the library multiplied by 100, plus the minor |
| 1033 | version number of the library. Hence, if the library version is 1.08, |
| 1034 | the returned value will be 108. |
| 1035 | |
| 1036 | If @var{ver_string} and/or @var{date_string} are non-NULL, they will be |
| 1037 | set to point at a constant string containing the library version and/or |
| 1038 | release date, respectively. |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 1039 | @end deftypefun |
| 1040 | |
Theodore Ts'o | 521e368 | 1997-04-29 17:48:10 +0000 | [diff] [blame^] | 1041 | @deftypefun int ext2fs_parse_version_string(const char *@var{ver_string}) |
| 1042 | |
| 1043 | This function takes a version string which may included in an |
| 1044 | application and returns a version code using the same algorithm used by |
| 1045 | @code{ext2fs_get_library_version}. It can be used by programs included |
| 1046 | in the @code{e2fsprogs} distribution to assure that they are using an |
| 1047 | up-to-date ext2 shared library. |
| 1048 | @end deftypefun |
Theodore Ts'o | 21c84b7 | 1997-04-29 16:15:03 +0000 | [diff] [blame] | 1049 | |
| 1050 | /* inline functions */ |
| 1051 | @deftypefun int ext2fs_group_of_blk (ext2_filsys @var{fs}, blk_t @var{blk}) |
| 1052 | @end deftypefun |
| 1053 | |
| 1054 | @deftypefun int ext2fs_group_of_ino (ext2_filsys @var{fs}, ino_t @var{ino}) |
| 1055 | @end deftypefun |
| 1056 | |
| 1057 | |
| 1058 | @c ---------------------------------------------------------------------- |
| 1059 | |
| 1060 | @node Concept Index, Function Index, EXT2FS Library Functions, Top |
| 1061 | @comment node-name, next, previous, up |
| 1062 | @unnumbered Concept Index |
| 1063 | @printindex cp |
| 1064 | |
| 1065 | @c ---------------------------------------------------------------------- |
| 1066 | |
| 1067 | @node Function Index, , Concept Index, Top |
| 1068 | @comment node-name, next, previous, up |
| 1069 | @unnumbered Function and Type Index |
| 1070 | @printindex fn |
| 1071 | |
| 1072 | |
| 1073 | @contents |
| 1074 | @bye |