diff options
Diffstat (limited to 'include/sqfs')
| -rw-r--r-- | include/sqfs/data_reader.h | 4 | ||||
| -rw-r--r-- | include/sqfs/dir_reader.h | 8 | ||||
| -rw-r--r-- | include/sqfs/inode.h | 3 | ||||
| -rw-r--r-- | include/sqfs/meta_reader.h | 4 | ||||
| -rw-r--r-- | include/sqfs/predef.h | 43 | ||||
| -rw-r--r-- | include/sqfs/xattr_reader.h | 4 |
6 files changed, 55 insertions, 11 deletions
diff --git a/include/sqfs/data_reader.h b/include/sqfs/data_reader.h index c967a70..29077b7 100644 --- a/include/sqfs/data_reader.h +++ b/include/sqfs/data_reader.h @@ -94,7 +94,7 @@ SQFS_API int sqfs_data_reader_load_fragment_table(sqfs_data_reader_t *data, * @param inode A pointer to the inode describing the file. * @param size Returns the size of the data read. * @param out Returns a pointer to the raw data that must be - * released using free. + * released using @ref sqfs_free. * * @return Zero on succcess, an @ref SQFS_ERROR value on failure. */ @@ -112,7 +112,7 @@ SQFS_API int sqfs_data_reader_get_fragment(sqfs_data_reader_t *data, * @param index The block index in the inodes block list. * @param size Returns the size of the data read. * @param out Returns a pointer to the raw data that must be - * released using free. + * released using @ref sqfs_free. * * @return Zero on succcess, an @ref SQFS_ERROR value on failure. */ diff --git a/include/sqfs/dir_reader.h b/include/sqfs/dir_reader.h index cf9f2a1..3bef7e3 100644 --- a/include/sqfs/dir_reader.h +++ b/include/sqfs/dir_reader.h @@ -231,7 +231,7 @@ SQFS_API int sqfs_dir_reader_find(sqfs_dir_reader_t *rd, const char *name); * * @param rd A pointer to a directory reader. * @param out Returns a pointer to a directory entry on success that can be - * freed with a single free call. + * freed with a single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure, a positive * number if the end of the current directory listing has been reached. @@ -246,7 +246,7 @@ SQFS_API int sqfs_dir_reader_read(sqfs_dir_reader_t *rd, * * @param rd A pointer to a directory reader. * @param out Returns a pointer to a generic inode that can be freed with a - * single free call. + * single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure. */ @@ -260,7 +260,7 @@ SQFS_API int sqfs_dir_reader_get_inode(sqfs_dir_reader_t *rd, * * @param rd A pointer to a directory reader. * @param out Returns a pointer to a generic inode that can be freed with a - * single free call. + * single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure. */ @@ -280,7 +280,7 @@ SQFS_API int sqfs_dir_reader_get_root_inode(sqfs_dir_reader_t *rd, * be used to separate path components. Resolving '.' or '..' is * not supported. * @param out Returns a pointer to a generic inode that can be freed with a - * single free call. + * single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure. */ diff --git a/include/sqfs/inode.h b/include/sqfs/inode.h index 5359b54..0bc33db 100644 --- a/include/sqfs/inode.h +++ b/include/sqfs/inode.h @@ -718,7 +718,8 @@ SQFS_API int sqfs_inode_get_file_block_start(const sqfs_inode_generic_t *inode, * fiddles the raw data out into a propperly aligned, external structure. * * @param inode A pointer to an inode. - * @param out Returns the index entry. Can be freed with a single free call. + * @param out Returns the index entry. Can be freed with a single + * @ref sqfs_free call. * @param index An index value between 0 and inodex_count. * * @return Zero on success, @ref SQFS_ERROR_OUT_OF_BOUNDS if the given index diff --git a/include/sqfs/meta_reader.h b/include/sqfs/meta_reader.h index bac1808..e0dc186 100644 --- a/include/sqfs/meta_reader.h +++ b/include/sqfs/meta_reader.h @@ -145,7 +145,7 @@ SQFS_API int sqfs_meta_reader_read_dir_header(sqfs_meta_reader_t *m, * * @param m A pointer to a meta data reader. * @param ent Returns a pointer to a directory entry. Can be released with a - * single free() call. + * single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure. */ @@ -167,7 +167,7 @@ SQFS_API int sqfs_meta_reader_read_dir_ent(sqfs_meta_reader_t *m, * @param offset A byte offset within the uncompressed block where the * inode is. * @param out Returns a pointer to an inode. Can be released with a - * single free() call. + * single @ref sqfs_free call. * * @return Zero on success, an @ref SQFS_ERROR value on failure. */ diff --git a/include/sqfs/predef.h b/include/sqfs/predef.h index 55ccc86..3254186 100644 --- a/include/sqfs/predef.h +++ b/include/sqfs/predef.h @@ -156,4 +156,47 @@ static SQFS_INLINE void *sqfs_copy(const void *obj) return NULL; } +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @brief Free a block of memory created by the squashfs library + * + * Some objects in the squashfs library allocate temporary chunks of memory + * and return pointers to them, with the expectation that the user takes care + * of freeing them memory again. + * + * In the past this worked without hitches, because most sane operating systems + * have a single, global C library that everything is linked against. On + * systems like Windows that have a huge fragmentation of runtime libraries + * this fails, because the library and application can easily end up linked + * against different runtime libraries, making it impossible for the program + * to free the memory. + * + * To re-create the same situation on Linux, one would have to link a program + * and the squashfs library dynamically, while linking at least one of them + * statically against the C runtime, or intentionally linking against two + * different runtimes. + * + * This function mitigates the arising problem by exposing the free() function + * of the libraries runtime to the application, so it can propperly release + * memory again to the correct heap. + * + * To maintain API/ABI compatibillity, it is guaranteed that for all versions + * of libsquashfs with major version 1, this function does nothing other than + * call free() on the C runtime that the library was linked against. If just + * calling free() works on your system, it will continue to work, and older + * application will continue to work with newer versions of libsquashfs 1.x. + * Going forward, new applications using libsquashfs should use this function + * instead for better portabillity. + * + * @param ptr A pointer to a memory block returned by a libsquashfs function. + */ +SQFS_API void sqfs_free(void *ptr); + +#ifdef __cplusplus +} +#endif + #endif /* SQFS_PREDEF_H */ diff --git a/include/sqfs/xattr_reader.h b/include/sqfs/xattr_reader.h index 8294bd8..a0242fb 100644 --- a/include/sqfs/xattr_reader.h +++ b/include/sqfs/xattr_reader.h @@ -160,7 +160,7 @@ SQFS_API int sqfs_xattr_reader_seek_kv(sqfs_xattr_reader_t *xr, * * @param xr A pointer to an xattr reader instance * @param key_out Used to return the decoded key. The underlying memory can be - * released using a single free() call. + * released using a single @ref sqfs_free call. * * @return Zero on success, a negative @ref SQFS_ERROR value on failure. */ @@ -181,7 +181,7 @@ int sqfs_xattr_reader_read_key(sqfs_xattr_reader_t *xr, * @param xr A pointer to an xattr reader instance. * @param key A pointer to the decoded key object. * @param val_out Used to return the decoded value. The underlying memory can - * be released using a single free() call. + * be released using a single @ref sqfs_free call. * * @return Zero on success, a negative @ref SQFS_ERROR value on failure. */ |