From 765fa2865aab97ea713c1715922e322b3cf599a7 Mon Sep 17 00:00:00 2001 From: Jia Tan Date: Wed, 8 Feb 2023 21:33:52 +0800 Subject: [PATCH] liblzma: Improve documentation in index.h All functions now explicitly specify parameter and return values. --- src/liblzma/api/lzma/index.h | 177 +++++++++++++++++++++++++---------- 1 file changed, 126 insertions(+), 51 deletions(-) diff --git a/src/liblzma/api/lzma/index.h b/src/liblzma/api/lzma/index.h index b478af37..64ec8350 100644 --- a/src/liblzma/api/lzma/index.h +++ b/src/liblzma/api/lzma/index.h @@ -317,6 +317,11 @@ typedef enum { * the given number of Streams and Blocks in lzma_index structure. This * value may vary between CPU architectures and also between liblzma versions * if the internal implementation is modified. + * + * \param streams Number of Streams + * \param blocks Number of Blocks + * + * \return Approximate memory in bytes needed in a lzma_index structure. */ extern LZMA_API(uint64_t) lzma_index_memusage( lzma_vli streams, lzma_vli blocks) lzma_nothrow; @@ -327,6 +332,10 @@ extern LZMA_API(uint64_t) lzma_index_memusage( * * This is a shorthand for lzma_index_memusage(lzma_index_stream_count(i), * lzma_index_block_count(i)). + * + * \param i Pointer to lzma_index structure + * + * \return Approximate memory in bytes used by the lzma_index structure. */ extern LZMA_API(uint64_t) lzma_index_memused(const lzma_index *i) lzma_nothrow; @@ -335,6 +344,9 @@ extern LZMA_API(uint64_t) lzma_index_memused(const lzma_index *i) /** * \brief Allocate and initialize a new lzma_index structure * + * \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). + * * \return On success, a pointer to an empty initialized lzma_index is * returned. If allocation fails, NULL is returned. */ @@ -346,6 +358,10 @@ extern LZMA_API(lzma_index *) lzma_index_init(const lzma_allocator *allocator) * \brief Deallocate lzma_index * * If i is NULL, this does nothing. + * + * \param i Pointer to lzma_index structure to deallocate + * \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). */ extern LZMA_API(void) lzma_index_end( lzma_index *i, const lzma_allocator *allocator) lzma_nothrow; @@ -355,8 +371,9 @@ extern LZMA_API(void) lzma_index_end( * \brief Add a new Block to lzma_index * * \param i Pointer to a lzma_index structure - * \param allocator Pointer to lzma_allocator, or NULL to - * use malloc() + * \param allocator lzma_allocator for custom allocator + * functions. Set to NULL to use malloc() + * and free(). * \param unpadded_size Unpadded Size of a Block. This can be * calculated with lzma_block_unpadded_size() * after encoding or decoding the Block. @@ -369,7 +386,8 @@ extern LZMA_API(void) lzma_index_end( * lzma_index_append() it is possible to read the next Block with * an existing iterator. * - * \return - LZMA_OK + * \return Possible lzma_ret values: + * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_DATA_ERROR: Compressed or uncompressed size of the * Stream or size of the Index field would grow too big. @@ -389,11 +407,15 @@ extern LZMA_API(lzma_ret) lzma_index_append( * lzma_index, because to decode Blocks, knowing the integrity check type * is needed. * - * The given Stream Flags are copied into internal preallocated structure - * in the lzma_index, thus the caller doesn't need to keep the *stream_flags - * available after calling this function. + * \param i Pointer to lzma_index structure + * \param stream_flags Pointer to lzma_stream_flags structure. This + * is copied into the internal preallocated + * structure, so the caller doesn't need to keep + * the flags' data available after calling this + * function. * - * \return - LZMA_OK + * \return Possible lzma_ret values: + * - LZMA_OK * - LZMA_OPTIONS_ERROR: Unsupported stream_flags->version. * - LZMA_PROG_ERROR */ @@ -411,6 +433,10 @@ extern LZMA_API(lzma_ret) lzma_index_stream_flags( * showing the Check types to the user. * * The bitmask is 1 << check_id, e.g. CRC32 is 1 << 1 and SHA-256 is 1 << 10. + * + * \param i Pointer to lzma_index structure + * + * \return Bitmask indicating which Check types are used in the lzma_index */ extern LZMA_API(uint32_t) lzma_index_checks(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -425,7 +451,8 @@ extern LZMA_API(uint32_t) lzma_index_checks(const lzma_index *i) * * By default, the amount of Stream Padding is assumed to be zero bytes. * - * \return - LZMA_OK + * \return Possible lzma_ret values: + * - LZMA_OK * - LZMA_DATA_ERROR: The file size would grow too big. * - LZMA_PROG_ERROR */ @@ -436,6 +463,10 @@ extern LZMA_API(lzma_ret) lzma_index_stream_padding( /** * \brief Get the number of Streams + * + * \param i Pointer to lzma_index structure + * + * \return Number of Streams in the lzma_index */ extern LZMA_API(lzma_vli) lzma_index_stream_count(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -446,6 +477,10 @@ extern LZMA_API(lzma_vli) lzma_index_stream_count(const lzma_index *i) * * This returns the total number of Blocks in lzma_index. To get number * of Blocks in individual Streams, use lzma_index_iter. + * + * \param i Pointer to lzma_index structure + * + * \return Number of blocks in the lzma_index */ extern LZMA_API(lzma_vli) lzma_index_block_count(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -455,6 +490,10 @@ extern LZMA_API(lzma_vli) lzma_index_block_count(const lzma_index *i) * \brief Get the size of the Index field as bytes * * This is needed to verify the Backward Size field in the Stream Footer. + * + * \param i Pointer to lzma_index structure + * + * \return Size in bytes of the Index */ extern LZMA_API(lzma_vli) lzma_index_size(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -466,6 +505,11 @@ extern LZMA_API(lzma_vli) lzma_index_size(const lzma_index *i) * If multiple lzma_indexes have been combined, this works as if the Blocks * were in a single Stream. This is useful if you are going to combine * Blocks from multiple Streams into a single new Stream. + * + * \param i Pointer to lzma_index structure + * + * \return Size in bytes of the Stream (if all Blocks are combined + * into one Stream). */ extern LZMA_API(lzma_vli) lzma_index_stream_size(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -476,6 +520,10 @@ extern LZMA_API(lzma_vli) lzma_index_stream_size(const lzma_index *i) * * This doesn't include the Stream Header, Stream Footer, Stream Padding, * or Index fields. + * + * \param i Pointer to lzma_index structure + * + * \return Size in bytes of all Blocks in the Stream(s) */ extern LZMA_API(lzma_vli) lzma_index_total_size(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -488,6 +536,10 @@ extern LZMA_API(lzma_vli) lzma_index_total_size(const lzma_index *i) * no Stream Padding, this function is identical to lzma_index_stream_size(). * If multiple lzma_indexes have been combined, this includes also the headers * of each separate Stream and the possible Stream Padding fields. + * + * \param i Pointer to lzma_index structure + * + * \return Total size of the .xz file in bytes */ extern LZMA_API(lzma_vli) lzma_index_file_size(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -495,6 +547,10 @@ extern LZMA_API(lzma_vli) lzma_index_file_size(const lzma_index *i) /** * \brief Get the uncompressed size of the file + * + * \param i Pointer to lzma_index structure + * + * \return Size in bytes of the uncompressed data in the file */ extern LZMA_API(lzma_vli) lzma_index_uncompressed_size(const lzma_index *i) lzma_nothrow lzma_attr_pure; @@ -503,9 +559,6 @@ extern LZMA_API(lzma_vli) lzma_index_uncompressed_size(const lzma_index *i) /** * \brief Initialize an iterator * - * \param iter Pointer to a lzma_index_iter structure - * \param i lzma_index to which the iterator will be associated - * * This function associates the iterator with the given lzma_index, and calls * lzma_index_iter_rewind() on the iterator. * @@ -518,6 +571,9 @@ extern LZMA_API(lzma_vli) lzma_index_uncompressed_size(const lzma_index *i) * * It is safe to make copies of an initialized lzma_index_iter, for example, * to easily restart reading at some particular position. + * + * \param iter Pointer to a lzma_index_iter structure + * \param i lzma_index to which the iterator will be associated */ extern LZMA_API(void) lzma_index_iter_init( lzma_index_iter *iter, const lzma_index *i) lzma_nothrow; @@ -528,6 +584,8 @@ extern LZMA_API(void) lzma_index_iter_init( * * Rewind the iterator so that next call to lzma_index_iter_next() will * return the first Block or Stream. + * + * \param iter Pointer to a lzma_index_iter structure */ extern LZMA_API(void) lzma_index_iter_rewind(lzma_index_iter *iter) lzma_nothrow; @@ -540,11 +598,11 @@ extern LZMA_API(void) lzma_index_iter_rewind(lzma_index_iter *iter) * \param mode Specify what kind of information the caller wants * to get. See lzma_index_iter_mode for details. * - * \return If next Block or Stream matching the mode was found, *iter - * is updated and this function returns false. If no Block or - * Stream matching the mode is found, *iter is not modified - * and this function returns true. If mode is set to an unknown - * value, *iter is not modified and this function returns true. + * \return lzma_bool: + * - true if no Block or Stream matching the mode is found. + * *iter is not updated (failure). + * - false if the next Block or Stream matching the mode was + * found. *iter is updated (success). */ extern LZMA_API(lzma_bool) lzma_index_iter_next( lzma_index_iter *iter, lzma_index_iter_mode mode) @@ -558,21 +616,26 @@ extern LZMA_API(lzma_bool) lzma_index_iter_next( * the Index field(s) and use lzma_index_iter_locate() to do random-access * reading with granularity of Block size. * - * \param iter Iterator that was earlier initialized with - * lzma_index_iter_init(). - * \param target Uncompressed target offset which the caller would - * like to locate from the Stream - * * If the target is smaller than the uncompressed size of the Stream (can be * checked with lzma_index_uncompressed_size()): * - Information about the Stream and Block containing the requested * uncompressed offset is stored into *iter. * - Internal state of the iterator is adjusted so that * lzma_index_iter_next() can be used to read subsequent Blocks or Streams. - * - This function returns false. * - * If target is greater than the uncompressed size of the Stream, *iter - * is not modified, and this function returns true. + * If the target is greater than the uncompressed size of the Stream, *iter + * is not modified. + * + * \param iter Iterator that was earlier initialized with + * lzma_index_iter_init(). + * \param target Uncompressed target offset which the caller would + * like to locate from the Stream + * + * \return lzma_bool: + * - true if the target is greater than or equal to the + * uncompressed size of the Stream (failure) + * - false if the target is smaller than the uncompressed size + * of the Stream (success) */ extern LZMA_API(lzma_bool) lzma_index_iter_locate( lzma_index_iter *iter, lzma_vli target) lzma_nothrow; @@ -585,15 +648,16 @@ extern LZMA_API(lzma_bool) lzma_index_iter_locate( * multi-Stream .xz file, or when combining multiple Streams into single * Stream. * - * \param dest lzma_index after which src is appended + * \param[out] dest lzma_index after which src is appended * \param src lzma_index to be appended after dest. If this * function succeeds, the memory allocated for src * is freed or moved to be part of dest, and all * iterators pointing to src will become invalid. - * \param allocator Custom memory allocator; can be NULL to use - * malloc() and free(). +* \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). * - * \return - LZMA_OK: lzma_indexes were concatenated successfully. + * \return Possible lzma_ret values: + * - LZMA_OK: lzma_indexes were concatenated successfully. * src is now a dangling pointer. * - LZMA_DATA_ERROR: *dest would grow too big. * - LZMA_MEM_ERROR @@ -607,6 +671,10 @@ extern LZMA_API(lzma_ret) lzma_index_cat(lzma_index *dest, lzma_index *src, /** * \brief Duplicate lzma_index * + * \param i Pointer to lzma_index structure to be duplicated + * \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). + * * \return A copy of the lzma_index, or NULL if memory allocation failed. */ extern LZMA_API(lzma_index *) lzma_index_dup( @@ -623,7 +691,8 @@ extern LZMA_API(lzma_index *) lzma_index_dup( * The valid `action' values for lzma_code() are LZMA_RUN and LZMA_FINISH. * It is enough to use only one of them (you can choose freely). * - * \return - LZMA_OK: Initialization succeeded, continue with lzma_code(). + * \return Possible lzma_ret values: + * - LZMA_OK: Initialization succeeded, continue with lzma_code(). * - LZMA_MEM_ERROR * - LZMA_PROG_ERROR */ @@ -636,7 +705,7 @@ extern LZMA_API(lzma_ret) lzma_index_encoder( * \brief Initialize .xz Index decoder * * \param strm Pointer to properly prepared lzma_stream - * \param i The decoded Index will be made available via + * \param[out] i The decoded Index will be made available via * this pointer. Initially this function will * set *i to NULL (the old value is ignored). If * decoding succeeds (lzma_code() returns @@ -652,11 +721,12 @@ extern LZMA_API(lzma_ret) lzma_index_encoder( * There is no need to use LZMA_FINISH, but it's allowed because it may * simplify certain types of applications. * - * \return - LZMA_OK: Initialization succeeded, continue with lzma_code(). + * \return Possible lzma_ret values: + * - LZMA_OK: Initialization succeeded, continue with lzma_code(). * - LZMA_MEM_ERROR * - LZMA_PROG_ERROR * - * liblzma 5.2.3 and older list also LZMA_MEMLIMIT_ERROR here + * \note liblzma 5.2.3 and older list also LZMA_MEMLIMIT_ERROR here * but that error code has never been possible from this * initialization function. */ @@ -668,21 +738,23 @@ extern LZMA_API(lzma_ret) lzma_index_decoder( /** * \brief Single-call .xz Index encoder * + * \note This function doesn't take allocator argument since all + * the internal data is allocated on stack. + * * \param i lzma_index to be encoded - * \param out Beginning of the output buffer - * \param out_pos The next byte will be written to out[*out_pos]. + * \param[out] out Beginning of the output buffer + * \param[out] out_pos The next byte will be written to out[*out_pos]. * *out_pos is updated only if encoding succeeds. * \param out_size Size of the out buffer; the first byte into * which no data is written to is out[out_size]. * - * \return - LZMA_OK: Encoding was successful. + * \return Possible lzma_ret values: + * - LZMA_OK: Encoding was successful. * - LZMA_BUF_ERROR: Output buffer is too small. Use * lzma_index_size() to find out how much output * space is needed. * - LZMA_PROG_ERROR * - * \note This function doesn't take allocator argument since all - * the internal data is allocated on stack. */ extern LZMA_API(lzma_ret) lzma_index_buffer_encode(const lzma_index *i, uint8_t *out, size_t *out_pos, size_t out_size) lzma_nothrow; @@ -691,24 +763,26 @@ extern LZMA_API(lzma_ret) lzma_index_buffer_encode(const lzma_index *i, /** * \brief Single-call .xz Index decoder * - * \param i If decoding succeeds, *i will point to a new + * \param[out] i If decoding succeeds, *i will point to a new * lzma_index, which the application has to * later free with lzma_index_end(). If an error * occurs, *i will be NULL. The old value of *i * is always ignored and thus doesn't need to be * initialized by the caller. - * \param memlimit Pointer to how much memory the resulting + * \param[out] memlimit Pointer to how much memory the resulting * lzma_index is allowed to require. The value * pointed by this pointer is modified if and only * if LZMA_MEMLIMIT_ERROR is returned. - * \param allocator Pointer to lzma_allocator, or NULL to use malloc() + * \param allocator lzma_allocator for custom allocator functions. + * Set to NULL to use malloc() and free(). * \param in Beginning of the input buffer * \param in_pos The next byte will be read from in[*in_pos]. * *in_pos is updated only if decoding succeeds. * \param in_size Size of the input buffer; the first byte that * won't be read is in[in_size]. * - * \return - LZMA_OK: Decoding was successful. + * \return Possible lzma_ret values: + * - LZMA_OK: Decoding was successful. * - LZMA_MEM_ERROR * - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached. * The minimum required memlimit value was stored to *memlimit. @@ -724,15 +798,6 @@ extern LZMA_API(lzma_ret) lzma_index_buffer_decode(lzma_index **i, /** * \brief Initialize a .xz file information decoder * - * \param strm Pointer to a properly prepared lzma_stream - * \param dest_index Pointer to a pointer where the decoder will put - * the decoded lzma_index. The old value - * of *dest_index is ignored (not freed). - * \param memlimit How much memory the resulting lzma_index is - * allowed to require. Use UINT64_MAX to - * effectively disable the limiter. - * \param file_size Size of the input .xz file - * * This decoder decodes the Stream Header, Stream Footer, Index, and * Stream Padding field(s) from the input .xz file and stores the resulting * combined index in *dest_index. This information can be used to get the @@ -777,7 +842,17 @@ extern LZMA_API(lzma_ret) lzma_index_buffer_decode(lzma_index **i, * - LZMA_MEMLIMIT_ERROR * - LZMA_PROG_ERROR * - * \return - LZMA_OK + * \param strm Pointer to a properly prepared lzma_stream + * \param[out] dest_index Pointer to a pointer where the decoder will put + * the decoded lzma_index. The old value + * of *dest_index is ignored (not freed). + * \param memlimit How much memory the resulting lzma_index is + * allowed to require. Use UINT64_MAX to + * effectively disable the limiter. + * \param file_size Size of the input .xz file + * + * \return Possible lzma_ret values: + * - LZMA_OK * - LZMA_MEM_ERROR * - LZMA_PROG_ERROR */