diff options
author | David Oberhollenzer <david.oberhollenzer@sigma-star.at> | 2020-03-03 19:43:54 +0100 |
---|---|---|
committer | David Oberhollenzer <david.oberhollenzer@sigma-star.at> | 2020-03-04 00:58:53 +0100 |
commit | 44c81eeffe9c8820b1009a7a5c728782aa5ebf40 (patch) | |
tree | 544eceb6dc5633018e5147c88ca9b07dd0fb54d9 /include | |
parent | 6f47796dc0761fac359ec59ce26c7af5154e538d (diff) |
Add a generic copying mechanism to sqfs_object_t
This patch adds a deep-copy callback to sqfs_object_t and removes the
copying mechanism from sqfs_compressor_t. This is also interesting for
other types.
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'include')
-rw-r--r-- | include/sqfs/block_processor.h | 2 | ||||
-rw-r--r-- | include/sqfs/block_writer.h | 2 | ||||
-rw-r--r-- | include/sqfs/compressor.h | 9 | ||||
-rw-r--r-- | include/sqfs/dir_writer.h | 2 | ||||
-rw-r--r-- | include/sqfs/io.h | 5 | ||||
-rw-r--r-- | include/sqfs/meta_writer.h | 2 | ||||
-rw-r--r-- | include/sqfs/predef.h | 20 |
7 files changed, 33 insertions, 9 deletions
diff --git a/include/sqfs/block_processor.h b/include/sqfs/block_processor.h index 2ad12c0..d3b6e12 100644 --- a/include/sqfs/block_processor.h +++ b/include/sqfs/block_processor.h @@ -43,6 +43,8 @@ * Internally it takes care of partitioning data in the correct block sizes, * adding tail-ens to fragment blocks, compressing the data, deduplicating data * and finally writing it to disk. + * + * This object is not copyable, i.e. @ref sqfs_copy will always return NULL. */ /** diff --git a/include/sqfs/block_writer.h b/include/sqfs/block_writer.h index bd1ddfc..674c0e7 100644 --- a/include/sqfs/block_writer.h +++ b/include/sqfs/block_writer.h @@ -34,6 +34,8 @@ * @implements sqfs_object_t * * @brief Abstracts writing and deduplicating of data and fragment blocks. + * + * This object is not copyable, i.e. @ref sqfs_copy will always return NULL. */ /** diff --git a/include/sqfs/compressor.h b/include/sqfs/compressor.h index 4292712..9a3508a 100644 --- a/include/sqfs/compressor.h +++ b/include/sqfs/compressor.h @@ -91,15 +91,6 @@ struct sqfs_compressor_t { */ sqfs_s32 (*do_block)(sqfs_compressor_t *cmp, const sqfs_u8 *in, sqfs_u32 size, sqfs_u8 *out, sqfs_u32 outsize); - - /** - * @brief Create an exact copt of agiven compressor - * - * @param cmp A pointer to a compressor object. - * - * @return A deep copy of the given compressor. - */ - sqfs_compressor_t *(*create_copy)(sqfs_compressor_t *cmp); }; /** diff --git a/include/sqfs/dir_writer.h b/include/sqfs/dir_writer.h index e4a26c7..dce5a79 100644 --- a/include/sqfs/dir_writer.h +++ b/include/sqfs/dir_writer.h @@ -58,6 +58,8 @@ * adding entries. Internally it fills data into a meta data writer and * generates an index that it can, on request, write to another meta data * writer used for inodes. + * + * This object is not copyable, i.e. @ref sqfs_copy will always return NULL. */ /** diff --git a/include/sqfs/io.h b/include/sqfs/io.h index 578c4fb..18c6810 100644 --- a/include/sqfs/io.h +++ b/include/sqfs/io.h @@ -63,6 +63,11 @@ typedef enum { * @extends sqfs_object_t * * @brief Abstracts file I/O to make it easy to embedd SquashFS. + * + * Files are only copyable if they are read only, i.e. if a file has been + * opened with write access, @ref sqfs_copy will always return NULL. The + * other data types inside libsquashfs assume this to hold for all + * implementations of this interface. */ struct sqfs_file_t { sqfs_object_t base; diff --git a/include/sqfs/meta_writer.h b/include/sqfs/meta_writer.h index be151cc..58968f5 100644 --- a/include/sqfs/meta_writer.h +++ b/include/sqfs/meta_writer.h @@ -46,6 +46,8 @@ * The main task of the meta data writer is to provide a simple append * function that transparently takes care of chopping data up into blocks, * compressing the blocks and pre-pending a header. + * + * This object is not copyable, i.e. @ref sqfs_copy will always return NULL. */ /** diff --git a/include/sqfs/predef.h b/include/sqfs/predef.h index 6ca3503..0e81933 100644 --- a/include/sqfs/predef.h +++ b/include/sqfs/predef.h @@ -121,6 +121,8 @@ typedef struct sqfs_xattr_id_table_t sqfs_xattr_id_table_t; */ typedef struct sqfs_object_t { void (*destroy)(struct sqfs_object_t *instance); + + struct sqfs_object_t *(*copy)(const struct sqfs_object_t *orig); } sqfs_object_t; /** @@ -135,4 +137,22 @@ static SQFS_INLINE void sqfs_destroy(void *obj) ((sqfs_object_t *)obj)->destroy(obj); } +/** + * @brief Create a deep copy of an object if possible. + * + * @memberof sqfs_object_t + * + * @param obj A pointer to an object + * + * @return A pointer to a new object, instantiated from the old on success, + * NULL on failure. + */ +static SQFS_INLINE void *sqfs_copy(const void *obj) +{ + if (((sqfs_object_t *)obj)->copy != NULL) + return ((sqfs_object_t *)obj)->copy(obj); + + return NULL; +} + #endif /* SQFS_PREDEF_H */ |