liblzma: Improve documentation in index.h

All functions now explicitly specify parameter and return values.
This commit is contained in:
Jia Tan 2023-02-08 21:33:52 +08:00
parent 421f2f2e16
commit 9c71db4e88

View File

@ -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
*/