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authorDenys Vlasenko2010-06-20 02:40:56 +0200
committerDenys Vlasenko2010-06-20 02:40:56 +0200
commitba73cfd28464f9ef926dfd27e264215d4c4f8b1f (patch)
tree1388876b477579cb6f43b4eb12b258b61bc8f010 /archival/libunarchive/unxz/xz_dec_lzma2.c
parent91d7ee31f766a13595c1042d375f8374f2c3675f (diff)
downloadbusybox-ba73cfd28464f9ef926dfd27e264215d4c4f8b1f.zip
busybox-ba73cfd28464f9ef926dfd27e264215d4c4f8b1f.tar.gz
unxz: update from XZ embedded git
function old new delta rc_reset - 21 +21 unpack_xz_stream 2342 2357 +15 lzma_reset 102 64 -38 lzma_len 506 443 -63 xz_dec_lzma2_run 1438 1374 -64 xz_dec_reset 73 - -73 lzma_main 2517 2183 -334 ------------------------------------------------------------------------------ (add/remove: 1/1 grow/shrink: 1/4 up/down: 36/-572) Total: -536 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival/libunarchive/unxz/xz_dec_lzma2.c')
-rw-r--r--archival/libunarchive/unxz/xz_dec_lzma2.c200
1 files changed, 110 insertions, 90 deletions
diff --git a/archival/libunarchive/unxz/xz_dec_lzma2.c b/archival/libunarchive/unxz/xz_dec_lzma2.c
index 37de6fc..da71cb4 100644
--- a/archival/libunarchive/unxz/xz_dec_lzma2.c
+++ b/archival/libunarchive/unxz/xz_dec_lzma2.c
@@ -34,7 +34,8 @@
*
* In multi-call mode, also these are true:
* end == size
- * size <= allocated
+ * size <= size_max
+ * allocated <= size
*
* Most of these variables are size_t to support single-call mode,
* in which the dictionary variables address the actual output
@@ -74,11 +75,20 @@ struct dictionary {
uint32_t size;
/*
- * Amount of memory allocated for the dictionary. A special
- * value of zero indicates that we are in single-call mode,
- * where the output buffer works as the dictionary.
+ * Maximum allowed dictionary size in multi-call mode.
+ * This is ignored in single-call mode.
+ */
+ 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 */
@@ -120,31 +130,31 @@ struct lzma_len_dec {
};
struct lzma_dec {
- /*
- * LZMA properties or related bit masks (number of literal
- * context bits, a mask dervied from the number of literal
- * position bits, and a mask dervied from the number
- * position bits)
- */
- uint32_t lc;
- uint32_t literal_pos_mask; /* (1 << lp) - 1 */
- uint32_t pos_mask; /* (1 << pb) - 1 */
-
- /* Types of the most recently seen LZMA symbols */
- enum lzma_state state;
-
/* Distances of latest four matches */
uint32_t rep0;
uint32_t rep1;
uint32_t rep2;
uint32_t rep3;
+ /* Types of the most recently seen LZMA symbols */
+ enum lzma_state state;
+
/*
* Length of a match. This is updated so that dict_repeat can
* be called again to finish repeating the whole match.
*/
uint32_t len;
+ /*
+ * LZMA properties or related bit masks (number of literal
+ * context bits, a mask dervied from the number of literal
+ * position bits, and a mask dervied from the number
+ * position bits)
+ */
+ uint32_t lc;
+ uint32_t literal_pos_mask; /* (1 << lp) - 1 */
+ uint32_t pos_mask; /* (1 << pb) - 1 */
+
/* If 1, it's a match. Otherwise it's a single 8-bit literal. */
uint16_t is_match[STATES][POS_STATES_MAX];
@@ -201,49 +211,59 @@ struct lzma_dec {
uint16_t literal[LITERAL_CODERS_MAX][LITERAL_CODER_SIZE];
};
+struct lzma2_dec {
+ /* Position in xz_dec_lzma2_run(). */
+ enum lzma2_seq {
+ SEQ_CONTROL,
+ SEQ_UNCOMPRESSED_1,
+ SEQ_UNCOMPRESSED_2,
+ SEQ_COMPRESSED_0,
+ SEQ_COMPRESSED_1,
+ SEQ_PROPERTIES,
+ SEQ_LZMA_PREPARE,
+ SEQ_LZMA_RUN,
+ SEQ_COPY
+ } sequence;
+
+ /* Next position after decoding the compressed size of the chunk. */
+ enum lzma2_seq next_sequence;
+
+ /* Uncompressed size of LZMA chunk (2 MiB at maximum) */
+ uint32_t uncompressed;
+
+ /*
+ * Compressed size of LZMA chunk or compressed/uncompressed
+ * size of uncompressed chunk (64 KiB at maximum)
+ */
+ uint32_t compressed;
+
+ /*
+ * True if dictionary reset is needed. This is false before
+ * the first chunk (LZMA or uncompressed).
+ */
+ bool need_dict_reset;
+
+ /*
+ * True if new LZMA properties are needed. This is false
+ * before the first LZMA chunk.
+ */
+ bool need_props;
+};
+
struct xz_dec_lzma2 {
- /* LZMA2 */
- struct {
- /* Position in xz_dec_lzma2_run(). */
- enum lzma2_seq {
- SEQ_CONTROL,
- SEQ_UNCOMPRESSED_1,
- SEQ_UNCOMPRESSED_2,
- SEQ_COMPRESSED_0,
- SEQ_COMPRESSED_1,
- SEQ_PROPERTIES,
- SEQ_LZMA_PREPARE,
- SEQ_LZMA_RUN,
- SEQ_COPY
- } sequence;
-
- /*
- * Next position after decoding the compressed size of
- * the chunk.
- */
- enum lzma2_seq next_sequence;
-
- /* Uncompressed size of LZMA chunk (2 MiB at maximum) */
- uint32_t uncompressed;
-
- /*
- * Compressed size of LZMA chunk or compressed/uncompressed
- * size of uncompressed chunk (64 KiB at maximum)
- */
- uint32_t compressed;
-
- /*
- * True if dictionary reset is needed. This is false before
- * the first chunk (LZMA or uncompressed).
- */
- bool need_dict_reset;
-
- /*
- * True if new LZMA properties are needed. This is false
- * before the first LZMA chunk.
- */
- bool need_props;
- } lzma2;
+ /*
+ * The order below is important on x86 to reduce code size and
+ * it shouldn't hurt on other platforms. Everything up to and
+ * including lzma.pos_mask are in the first 128 bytes on x86-32,
+ * which allows using smaller instructions to access those
+ * variables. On x86-64, fewer variables fit into the first 128
+ * bytes, but this is still the best order without sacrificing
+ * the readability by splitting the structures.
+ */
+ struct rc_dec rc;
+ struct dictionary dict;
+ struct lzma2_dec lzma2;
+ struct lzma_dec lzma;
/*
* Temporary buffer which holds small number of input bytes between
@@ -253,10 +273,6 @@ struct xz_dec_lzma2 {
uint32_t size;
uint8_t buf[3 * LZMA_IN_REQUIRED];
} temp;
-
- struct dictionary dict;
- struct rc_dec rc;
- struct lzma_dec lzma;
};
/**************
@@ -269,7 +285,7 @@ struct xz_dec_lzma2 {
*/
static void XZ_FUNC dict_reset(struct dictionary *dict, struct xz_buf *b)
{
- if (dict->allocated == 0) {
+ if (DEC_IS_SINGLE(dict->mode)) {
dict->buf = b->out + b->out_pos;
dict->end = b->out_size - b->out_pos;
}
@@ -379,7 +395,7 @@ static void XZ_FUNC dict_uncompressed(
if (dict->full < dict->pos)
dict->full = dict->pos;
- if (dict->allocated != 0) {
+ if (DEC_IS_MULTI(dict->mode)) {
if (dict->pos == dict->end)
dict->pos = 0;
@@ -404,7 +420,7 @@ static uint32_t XZ_FUNC dict_flush(struct dictionary *dict, struct xz_buf *b)
{
size_t copy_size = dict->pos - dict->start;
- if (dict->allocated != 0) {
+ if (DEC_IS_MULTI(dict->mode)) {
if (dict->pos == dict->end)
dict->pos = 0;
@@ -422,7 +438,7 @@ static uint32_t XZ_FUNC dict_flush(struct dictionary *dict, struct xz_buf *b)
*****************/
/* Reset the range decoder. */
-static __always_inline void XZ_FUNC rc_reset(struct rc_dec *rc)
+static void XZ_FUNC rc_reset(struct rc_dec *rc)
{
rc->range = (uint32_t)-1;
rc->code = 0;
@@ -1088,28 +1104,27 @@ XZ_EXTERN NOINLINE enum xz_ret XZ_FUNC xz_dec_lzma2_run(
return XZ_OK;
}
-XZ_EXTERN struct xz_dec_lzma2 * XZ_FUNC xz_dec_lzma2_create(uint32_t dict_max)
+XZ_EXTERN struct xz_dec_lzma2 * XZ_FUNC xz_dec_lzma2_create(
+ enum xz_mode mode, uint32_t dict_max)
{
- struct xz_dec_lzma2 *s;
-
- /* Maximum supported dictionary by this implementation is 3 GiB. */
- if (dict_max > ((uint32_t)3 << 30))
- return NULL;
-
- s = kmalloc(sizeof(*s), GFP_KERNEL);
+ struct xz_dec_lzma2 *s = kmalloc(sizeof(*s), GFP_KERNEL);
if (s == NULL)
return NULL;
- if (dict_max > 0) {
+ s->dict.mode = mode;
+ s->dict.size_max = dict_max;
+
+ if (DEC_IS_PREALLOC(mode)) {
s->dict.buf = vmalloc(dict_max);
if (s->dict.buf == NULL) {
kfree(s);
return NULL;
}
+ } else if (DEC_IS_DYNALLOC(mode)) {
+ s->dict.buf = NULL;
+ s->dict.allocated = 0;
}
- s->dict.allocated = dict_max;
-
return s;
}
@@ -1123,18 +1138,23 @@ XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_lzma2_reset(
s->dict.size = 2 + (props & 1);
s->dict.size <<= (props >> 1) + 11;
- if (s->dict.allocated > 0 && s->dict.allocated < s->dict.size) {
-#ifdef XZ_REALLOC_DICT_BUF
- s->dict.buf = XZ_REALLOC_DICT_BUF(s->dict.buf, s->dict.size);
- if (!s->dict.buf)
- return XZ_MEMLIMIT_ERROR;
- s->dict.allocated = s->dict.size;
-#else
- return XZ_MEMLIMIT_ERROR;
-#endif
- }
+ if (DEC_IS_MULTI(s->dict.mode)) {
+ if (s->dict.size > s->dict.size_max)
+ return XZ_MEMLIMIT_ERROR;
- s->dict.end = s->dict.size;
+ s->dict.end = s->dict.size;
+
+ if (DEC_IS_DYNALLOC(s->dict.mode)) {
+ if (s->dict.allocated < s->dict.size) {
+ vfree(s->dict.buf);
+ s->dict.buf = vmalloc(s->dict.size);
+ if (s->dict.buf == NULL) {
+ s->dict.allocated = 0;
+ return XZ_MEM_ERROR;
+ }
+ }
+ }
+ }
s->lzma.len = 0;
@@ -1148,7 +1168,7 @@ XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_lzma2_reset(
XZ_EXTERN void XZ_FUNC xz_dec_lzma2_end(struct xz_dec_lzma2 *s)
{
- if (s->dict.allocated > 0)
+ if (DEC_IS_MULTI(s->dict.mode))
vfree(s->dict.buf);
kfree(s);