diff options
| -rw-r--r-- | toys/pending/xzcat.c | 103 |
1 files changed, 23 insertions, 80 deletions
diff --git a/toys/pending/xzcat.c b/toys/pending/xzcat.c index a90a4a90..951ead00 100644 --- a/toys/pending/xzcat.c +++ b/toys/pending/xzcat.c @@ -23,27 +23,9 @@ config XZCAT // BEGIN xz.h /** - * enum xz_mode - Operation mode - * - * @XZ_DYNALLOC: Multi-call mode. The LZMA2 dictionary is - * allocated once the required size has been - * parsed from the stream headers. If the - * allocation fails, xz_dec_run() will return - * XZ_MEM_ERROR. - * - * xzcat uses only XZ_DEC_DYNALLOC, though xz-embedded supports - * XZ_DEC_SINGLE and XZ_DEC_PREALLOC - */ -enum xz_mode { - XZ_DYNALLOC -}; - -/** * enum xz_ret - Return codes * @XZ_OK: Everything is OK so far. More input or more - * output space is required to continue. This - * return code is possible only in multi-call mode - * (XZ_PREALLOC or XZ_DYNALLOC). + * output space is required to continue. * @XZ_STREAM_END: Operation finished successfully. * @XZ_UNSUPPORTED_CHECK: Integrity check type is not supported. Decoding * is still possible in multi-call mode by simply @@ -53,17 +35,12 @@ enum xz_mode { * which is not used in the kernel. Unsupported * check types return XZ_OPTIONS_ERROR if * XZ_DEC_ANY_CHECK was not defined at build time. - * @XZ_MEM_ERROR: Allocating memory failed. This return code is - * possible only if the decoder was initialized - * with XZ_DYNALLOC. The amount of memory that was - * tried to be allocated was no more than the + * @XZ_MEM_ERROR: Allocating memory failed. The amount of memory + * that was tried to be allocated was no more than the * dict_max argument given to xz_dec_init(). * @XZ_MEMLIMIT_ERROR: A bigger LZMA2 dictionary would be needed than * allowed by the dict_max argument given to - * xz_dec_init(). This return value is possible - * only in multi-call mode (XZ_PREALLOC or - * XZ_DYNALLOC); the single-call mode (XZ_SINGLE) - * ignores the dict_max argument. + * xz_dec_init(). * @XZ_FORMAT_ERROR: File format was not recognized (wrong magic * bytes). * @XZ_OPTIONS_ERROR: This implementation doesn't support the requested @@ -75,18 +52,12 @@ enum xz_mode { * different between multi-call and single-call * mode; more information below. * - * In multi-call mode, XZ_BUF_ERROR is returned when two consecutive calls - * to XZ code cannot consume any input and cannot produce any new output. - * This happens when there is no new input available, or the output buffer - * is full while at least one output byte is still pending. Assuming your - * code is not buggy, you can get this error only when decoding a compressed - * stream that is truncated or otherwise corrupt. - * - * In single-call mode, XZ_BUF_ERROR is returned only when the output buffer - * is too small or the compressed input is corrupt in a way that makes the - * decoder produce more output than the caller expected. When it is - * (relatively) clear that the compressed input is truncated, XZ_DATA_ERROR - * is used instead of XZ_BUF_ERROR. + * XZ_BUF_ERROR is returned when two consecutive calls to XZ code cannot + * consume any input and cannot produce any new output. This happens when + * there is no new input available, or the output buffer is full while at + * least one output byte is still pending. Assuming your code is not buggy, + * you can get this error only when decoding a compressed stream that is + * truncated or otherwise corrupt. */ enum xz_ret { XZ_OK, @@ -135,8 +106,7 @@ struct xz_dec; * xz_dec_init() - Allocate and initialize a XZ decoder state * @mode: Operation mode * @dict_max: Maximum size of the LZMA2 dictionary (history buffer) for - * multi-call decoding. This is ignored in single-call mode - * (mode == XZ_SINGLE). LZMA2 dictionary is always 2^n bytes + * multi-call decoding. LZMA2 dictionary is always 2^n bytes * or 2^n + 2^(n-1) bytes (the latter sizes are less common * in practice), so other values for dict_max don't make sense. * In the kernel, dictionary sizes of 64 KiB, 128 KiB, 256 KiB, @@ -144,7 +114,6 @@ struct xz_dec; * except for kernel and initramfs images where a bigger * dictionary can be fine and useful. * - * Multi-call mode with dynamically allocated dictionary (XZ_DYNALLOC): * dict_max specifies the maximum allowed dictionary size that xz_dec_run() * may allocate once it has parsed the dictionary size from the stream * headers. This way excessive allocations can be avoided while still @@ -155,7 +124,7 @@ struct xz_dec; * ready to be used with xz_dec_run(). If memory allocation fails, * xz_dec_init() returns NULL. */ -struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max); +struct xz_dec *xz_dec_init(uint32_t dict_max); /** * xz_dec_run() - Run the XZ decoder @@ -250,7 +219,7 @@ void do_xzcat(int fd, char *name) * Support up to 64 MiB dictionary. The actually needed memory * is allocated once the headers have been parsed. */ - s = xz_dec_init(XZ_DYNALLOC, 1 << 26); + s = xz_dec_init(1 << 26); if (s == NULL) { msg = "Memory allocation failed\n"; goto error; @@ -406,8 +375,6 @@ static inline void put_unaligned_be32(uint32_t val, uint8_t *buf) # define get_le32 get_unaligned_le32 #endif -#define XZ_DEC_DYNALLOC - /* * If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ. * XZ_DEC_BCJ is used to enable generic support for BCJ decoders. @@ -425,8 +392,7 @@ static inline void put_unaligned_be32(uint32_t val, uint8_t *buf) * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used * before calling xz_dec_lzma2_run(). */ -struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, - uint32_t dict_max); +struct xz_dec_lzma2 *xz_dec_lzma2_create(uint32_t dict_max); /* * Decode the LZMA2 properties (one byte) and reset the decoder. Return @@ -1239,13 +1205,11 @@ static inline uint32_t lzma_get_dist_state(uint32_t len) * These are always true: * start <= pos <= full <= end * pos <= limit <= end - * - * In multi-call mode, also these are true: * end == size * size <= size_max * allocated <= size * - * Most of these variables are size_t to support single-call mode, + * Most of these variables are size_t as a relic of single-call mode, * in which the dictionary variables address the actual output * buffer directly. */ @@ -1268,11 +1232,7 @@ struct dictionary { /* Write limit; we don't write to buf[limit] or later bytes. */ size_t limit; - /* - * End of the dictionary buffer. In multi-call mode, this is - * the same as the dictionary size. In single-call mode, this - * indicates the size of the output buffer. - */ + /* End of the dictionary buffer. This is the same as the dictionary size. */ size_t end; /* @@ -1283,20 +1243,14 @@ struct dictionary { uint32_t size; /* - * Maximum allowed dictionary size in multi-call mode. - * This is ignored in single-call mode. + * Maximum allowed dictionary size. */ uint32_t size_max; /* * Amount of memory currently allocated for the dictionary. - * This is used only with XZ_DYNALLOC. (With XZ_PREALLOC, - * size_max is always the same as the allocated size.) */ uint32_t allocated; - - /* Operation mode */ - enum xz_mode mode; }; /* Range decoder */ @@ -1487,11 +1441,8 @@ struct xz_dec_lzma2 { * Dictionary * **************/ -/* - * Reset the dictionary state. When in single-call mode, set up the beginning - * of the dictionary to point to the actual output buffer. - */ -static void dict_reset(struct dictionary *dict, struct xz_buf *b) +/* Reset the dictionary state. */ +static void dict_reset(struct dictionary *dict) { dict->start = 0; dict->pos = 0; @@ -2171,7 +2122,7 @@ enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, if (tmp >= 0xE0 || tmp == 0x01) { s->lzma2.need_props = 1; s->lzma2.need_dict_reset = 0; - dict_reset(&s->dict, b); + dict_reset(&s->dict); } else if (s->lzma2.need_dict_reset) { return XZ_DATA_ERROR; } @@ -2297,16 +2248,13 @@ enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, return XZ_OK; } -struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, - uint32_t dict_max) +struct xz_dec_lzma2 *xz_dec_lzma2_create(uint32_t dict_max) { struct xz_dec_lzma2 *s = malloc(sizeof(*s)); if (s == NULL) return NULL; - s->dict.mode = mode; s->dict.size_max = dict_max; - s->dict.buf = NULL; s->dict.allocated = 0; @@ -2439,9 +2387,6 @@ struct xz_dec { /* Type of the integrity check calculated from uncompressed data */ enum xz_check check_type; - /* Operation mode */ - enum xz_mode mode; - /* * True if the next call to xz_dec_run() is allowed to return * XZ_BUF_ERROR. @@ -3144,21 +3089,19 @@ enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b) return ret; } -struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max) +struct xz_dec *xz_dec_init(uint32_t dict_max) { struct xz_dec *s = malloc(sizeof(*s)); if (!s) return NULL; - s->mode = mode; - #ifdef XZ_DEC_BCJ s->bcj = malloc(sizeof(*s->bcj)); if (!s->bcj) goto error_bcj; #endif - s->lzma2 = xz_dec_lzma2_create(mode, dict_max); + s->lzma2 = xz_dec_lzma2_create(dict_max); if (s->lzma2 == NULL) goto error_lzma2; |