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-rw-r--r--lzip_decompress.c67
1 files changed, 32 insertions, 35 deletions
diff --git a/lzip_decompress.c b/lzip_decompress.c
index 157a798..492523d 100644
--- a/lzip_decompress.c
+++ b/lzip_decompress.c
@@ -1,7 +1,7 @@
/*
* LZIP decompressor
*
- * Copyright (C) 2016-2021 Antonio Diaz Diaz.
+ * Copyright (C) 2016-2024 Antonio Diaz Diaz.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
@@ -32,17 +32,17 @@ static inline State St_set_char(const State st)
static inline State St_set_match(const State st)
{
- return ((st < 7) ? 7 : 10);
+ return (st < 7) ? 7 : 10;
}
static inline State St_set_rep(const State st)
{
- return ((st < 7) ? 8 : 11);
+ return (st < 7) ? 8 : 11;
}
static inline State St_set_short_rep(const State st)
{
- return ((st < 7) ? 9 : 11);
+ return (st < 7) ? 9 : 11;
}
@@ -189,12 +189,12 @@ static inline void CRC32_update_buf(uint32_t * const crc,
STATIC_RW_DATA const uint8_t lzip_magic[4] = { 0x4C, 0x5A, 0x49, 0x50 }; /* "LZIP" */
-typedef uint8_t Lzip_header[6]; /* 0-3 magic bytes */
+enum { Lh_size = 6 };
+typedef uint8_t Lzip_header[Lh_size]; /* 0-3 magic bytes */
/* 4 version */
/* 5 coded dictionary size */
-enum { Lh_size = 6 };
-static inline bool Lh_verify_magic(const Lzip_header data)
+static inline bool Lh_check_magic(const Lzip_header data)
{
int i;
@@ -205,34 +205,34 @@ static inline bool Lh_verify_magic(const Lzip_header data)
}
/* detect (truncated) header */
-static inline bool Lh_verify_prefix(const Lzip_header data, const int sz)
+static inline bool Lh_check_prefix(const Lzip_header data, const int sz)
{
int i;
for (i = 0; i < sz && i < 4; ++i)
if (data[i] != lzip_magic[i])
return false;
- return (sz > 0);
+ return sz > 0;
}
/* detect corrupt header */
-static inline bool Lh_verify_corrupt(const Lzip_header data)
+static inline bool Lh_check_corrupt(const Lzip_header data)
{
int matches = 0;
int i;
for (i = 0; i < 4; ++i)
if (data[i] == lzip_magic[i])
++matches;
- return (matches > 1 && matches < 4);
+ return matches > 1 && matches < 4;
}
-static inline bool Lh_verify_version(const Lzip_header data)
+static inline bool Lh_check_version(const Lzip_header data)
{
- return (data[4] == 1);
+ return data[4] == 1;
}
static inline unsigned Lh_get_dictionary_size(const Lzip_header data)
{
- unsigned sz = (1 << (data[5] & 0x1F));
+ unsigned sz = 1 << (data[5] & 0x1F);
if (sz > min_dictionary_size)
sz -= (sz / 16) * ((data[5] >> 5) & 7);
@@ -240,11 +240,11 @@ static inline unsigned Lh_get_dictionary_size(const Lzip_header data)
}
-typedef uint8_t Lzip_trailer[20];
+enum { Lt_size = 20 };
+typedef uint8_t Lzip_trailer[Lt_size];
/* 0-3 CRC32 of the uncompressed data */
/* 4-11 size of the uncompressed data */
/* 12-19 member size including header and trailer */
-enum { Lt_size = 20 };
static inline unsigned Lt_get_data_crc(const Lzip_trailer data)
{
@@ -364,9 +364,9 @@ static inline void Rd_load(struct Range_decoder * const rdec)
int i;
rdec->code = 0;
- for (i = 0; i < 5; ++i)
- rdec->code = (rdec->code << 8) | Rd_get_byte(rdec);
rdec->range = 0xFFFFFFFFU;
+ Rd_get_byte(rdec); /* discard first byte of the LZMA stream */
+ for (i = 0; i < 4; ++i) rdec->code = (rdec->code << 8) | Rd_get_byte(rdec);
}
static inline void Rd_normalize(struct Range_decoder * const rdec)
@@ -500,11 +500,12 @@ static inline unsigned Rd_decode_len(struct Range_decoder * const rdec,
const int pos_state)
{
if (Rd_decode_bit(rdec, &lm->choice1) == 0)
- return Rd_decode_tree3(rdec, lm->bm_low[pos_state]);
+ return min_match_len +
+ Rd_decode_tree3(rdec, lm->bm_low[pos_state]);
if (Rd_decode_bit(rdec, &lm->choice2) == 0)
- return len_low_symbols +
+ return min_match_len + len_low_symbols +
Rd_decode_tree3(rdec, lm->bm_mid[pos_state]);
- return len_low_symbols + len_mid_symbols +
+ return min_match_len + len_low_symbols + len_mid_symbols +
Rd_decode_tree8(rdec, lm->bm_high);
}
@@ -668,7 +669,7 @@ LZd_data_position(const struct LZ_decoder * const d)
}
-static bool LZd_verify_trailer(struct LZ_decoder * const d)
+static bool LZd_check_trailer(struct LZ_decoder * const d)
{
Lzip_trailer trailer;
int i = 0;
@@ -676,9 +677,9 @@ static bool LZd_verify_trailer(struct LZ_decoder * const d)
while (i < Lt_size)
trailer[i++] = Rd_get_byte(d->rdec);
- return (Lt_get_data_crc(trailer) == LZd_crc(d) &&
+ return Lt_get_data_crc(trailer) == LZd_crc(d) &&
Lt_get_data_size(trailer) == LZd_data_position(d) &&
- Lt_get_member_size(trailer) == Rd_member_position(d->rdec));
+ Lt_get_member_size(trailer) == Rd_member_position(d->rdec);
}
@@ -736,11 +737,11 @@ static int LZd_decode_member(struct LZ_decoder * const d)
rep0 = distance;
}
state = St_set_rep(state);
- len = min_match_len + Rd_decode_len(rdec, &d->rep_len_model, pos_state);
+ len = Rd_decode_len(rdec, &d->rep_len_model, pos_state);
} else { /* match */
unsigned distance;
- len = min_match_len + Rd_decode_len(rdec, &d->match_len_model, pos_state);
+ len = Rd_decode_len(rdec, &d->match_len_model, pos_state);
distance = Rd_decode_tree6(rdec, d->bm_dis_slot[get_len_state(len)]);
if (distance >= start_dis_model) {
const unsigned dis_slot = distance;
@@ -760,15 +761,11 @@ static int LZd_decode_member(struct LZ_decoder * const d)
if (d->write_error)
return LZIP_WRITE_ERROR;
if (len == min_match_len) { /* End Of Stream marker */
- if (LZd_verify_trailer(d))
+ if (LZd_check_trailer(d))
return 0;
else
return LZIP_BAD_CRC;
}
- if (len == min_match_len + 1) { /* Sync Flush marker */
- Rd_load(rdec);
- continue;
- }
return LZIP_BAD_DATA; /* unknown marker */
}
}
@@ -820,18 +817,18 @@ int lzip_decompress(unsigned char *inbuf, long in_len,
if (Rd_finished(&rdec)) { /* End Of File */
if (first_member)
retval = LZIP_HEADER1_EOF;
- else if (Lh_verify_prefix(header, size))
+ else if (Lh_check_prefix(header, size))
retval = LZIP_HEADER2_EOF;
break;
}
- if (!Lh_verify_magic(header)) {
+ if (!Lh_check_magic(header)) {
if (first_member)
retval = LZIP_BAD_MAGIC1;
- else if (Lh_verify_corrupt(header))
+ else if (Lh_check_corrupt(header))
retval = LZIP_BAD_MAGIC2;
break;
}
- if (!Lh_verify_version(header)) {
+ if (!Lh_check_version(header)) {
retval = LZIP_BAD_VERSION;
break;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-28 05:28:24 +0000