diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/sqfs/dir_writer.h | 66 |
1 files changed, 64 insertions, 2 deletions
diff --git a/include/sqfs/dir_writer.h b/include/sqfs/dir_writer.h index 81a651c..c390050 100644 --- a/include/sqfs/dir_writer.h +++ b/include/sqfs/dir_writer.h @@ -58,6 +58,30 @@ * writer used for inodes. */ +/** + * @enum SQFS_DIR_WRITER_CREATE_FLAGS + * + * @brief Flags that can be set for @ref sqfs_dir_writer_create + */ +typedef enum { + /** + * @brief Record all inode locations to create an export table. + * + * For NFS export support, SquashFS needs an extra table that maps + * inode numbers directly to on-disk locations. + * + * Since the @ref sqfs_dir_writer_t "sees" all inode numbers and + * coresponding locations and easily create such a table. + * + * If this flag is set for @ref sqfs_dir_writer_create, the result + * directory wrter collects such a table which it can then write to + * disk using @ref sqfs_dir_writer_write_export_table. + */ + SQFS_DIR_WRITER_CREATE_EXPORT_TABLE = 0x01, + + SQFS_DIR_WRITER_CREATE_ALL_FLAGS = 0x01 +} SQFS_DIR_WRITER_CREATE_FLAGS; + #ifdef __cplusplus extern "C" { #endif @@ -69,11 +93,13 @@ extern "C" { * * @param dm A pointer to a meta data writer that the generated directory * entries should be written to. + * @param flags A combination of @ref SQFS_DIR_WRITER_CREATE_FLAGS. * * @return A pointer to a directory writer on success, NULL on - * allocation failure. + * allocation failure or if flags has unknown flags set. */ -SQFS_API sqfs_dir_writer_t *sqfs_dir_writer_create(sqfs_meta_writer_t *dm); +SQFS_API sqfs_dir_writer_t *sqfs_dir_writer_create(sqfs_meta_writer_t *dm, + sqfs_u32 flags); /** * @brief Destroy a directory writer and free all its memory. @@ -217,6 +243,42 @@ SQFS_API sqfs_inode_generic_t *sqfs_dir_writer_create_inode(const sqfs_dir_writer_t *writer, size_t hlinks, sqfs_u32 xattr, sqfs_u32 parent_ino); +/** + * @brief Write an export table to a SquashFS image. + * + * @memberof sqfs_dir_writer_t + * + * If the @ref sqfs_dir_writer_t was created with the + * @ref SQFS_DIR_WRITER_CREATE_EXPORT_TABLE flag set, it has an internal table + * that maps all inode numbers to inode references. After writing the fragment + * table, this function can be used to write this inode mapping table for NFS + * export support. + * + * It is safe to call this function if the writer has been created without the + * flag. In this case, it is simply a noop. + * + * In theory, the writer "sees" the entire directory tree and for each entry, + * the inode number and on-disk location, so it can build this table. The only + * inode it never sees is the root inode, so that information has to be passed + * to this function to add it to the table just before writing it to disk. + * + * @param writer A pointer to a directory writer object. + * @param file The ouput file to write the table to. + * @param cmp The compressor to use to compress the table. + * @param root_inode_num The inode number of the root inode. + * @param root_inode_ref An inode reference for the root inode. + * @param super A pointer to the super block. Location of the export table and + * the exportable flag are set. + * + * @return Zero on success, a @ref E_SQFS_ERROR value on failure. + */ +SQFS_API int sqfs_dir_writer_write_export_table(sqfs_dir_writer_t *writer, + sqfs_file_t *file, + sqfs_compressor_t *cmp, + sqfs_u32 root_inode_num, + sqfs_u64 root_inode_ref, + sqfs_super_t *super); + #ifdef __cplusplus } #endif |