From 434f95960ad484d09ce0cad5dbf44b11312963f8 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 8 Apr 2018 13:32:47 +0200 Subject: [PATCH] lzop: code shrink by using header_t matching on-disk layout function old new delta add_bytes_to_chksum 37 47 +10 lzo_decompress 524 532 +8 init_chksum 14 21 +7 chksum_getresult 13 17 +4 f_read 33 28 -5 f_write8 20 - -20 f_write32 22 - -22 f_write16 25 - -25 f_write 36 - -36 do_lzo_compress 328 232 -96 do_lzo_decompress 526 411 -115 ------------------------------------------------------------------------------ (add/remove: 0/4 grow/shrink: 4/3 up/down: 29/-319) Total: -290 bytes Signed-off-by: Denys Vlasenko --- archival/lzop.c | 331 ++++++++++++++++++++++-------------------------- 1 file changed, 154 insertions(+), 177 deletions(-) diff --git a/archival/lzop.c b/archival/lzop.c index fef8cdba3..419e1e21f 100644 --- a/archival/lzop.c +++ b/archival/lzop.c @@ -438,36 +438,33 @@ typedef struct chksum_t { } chksum_t; typedef struct header_t { - unsigned version; - unsigned lib_version; - unsigned version_needed_to_extract; - uint32_t flags; - uint32_t mode; - uint32_t mtime; - uint32_t gmtdiff; - uint32_t header_checksum; - - uint32_t extra_field_len; - uint32_t extra_field_checksum; - - unsigned char method; - unsigned char level; - - /* info */ - char name[255+1]; + /* used to have auxiliary fields here */ + + /* Starting from here, the layout and endianness + * are exactly in on-disk format. + */ + uint16_t version_be16; + uint16_t lib_version_be16; + uint16_t version_needed_to_extract_be16; + uint8_t method; + uint8_t level; + uint32_t flags32; /* be32 on disk, but we keep them in native order */ + uint32_t mode_be32; + uint32_t mtime_be32; + uint32_t gmtdiff_be32; + char len_and_name[1+255+1]; } header_t; struct globals { /*const uint32_t *lzo_crc32_table;*/ - chksum_t chksum_in; - chksum_t chksum_out; + chksum_t chksum; } FIX_ALIASING; #define G (*(struct globals*)bb_common_bufsiz1) -#define INIT_G() do { setup_common_bufsiz(); } while (0) //#define G (*ptr_to_globals) -//#define INIT_G() do { -// SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); -//} while (0) +#define INIT_G() do { \ + setup_common_bufsiz(); \ + /*SET_PTR_TO_GLOBALS(xzalloc(sizeof(G)));*/ \ +} while (0) /**********************************************************************/ @@ -548,24 +545,24 @@ lzo_crc32(uint32_t c, const uint8_t* buf, unsigned len) } /**********************************************************************/ -static void init_chksum(chksum_t *ct) +static void init_chksum(void) { - ct->f_adler32 = ADLER32_INIT_VALUE; - ct->f_crc32 = CRC32_INIT_VALUE; + G.chksum.f_adler32 = ADLER32_INIT_VALUE; + G.chksum.f_crc32 = CRC32_INIT_VALUE; } -static void add_bytes_to_chksum(chksum_t *ct, const void* buf, int cnt) +static void add_bytes_to_chksum(const void* buf, int cnt) { /* We need to handle the two checksums at once, because at the * beginning of the header, we don't know yet which one we'll * eventually need */ - ct->f_adler32 = lzo_adler32(ct->f_adler32, (const uint8_t*)buf, cnt); - ct->f_crc32 = lzo_crc32(ct->f_crc32, (const uint8_t*)buf, cnt); + G.chksum.f_adler32 = lzo_adler32(G.chksum.f_adler32, (const uint8_t*)buf, cnt); + G.chksum.f_crc32 = lzo_crc32(G.chksum.f_crc32, (const uint8_t*)buf, cnt); } -static uint32_t chksum_getresult(chksum_t *ct, const header_t *h) +static uint32_t chksum_getresult(uint32_t h_flags32) { - return (h->flags & F_H_CRC32) ? ct->f_crc32 : ct->f_adler32; + return (h_flags32 & F_H_CRC32) ? G.chksum.f_crc32 : G.chksum.f_adler32; } /**********************************************************************/ @@ -575,50 +572,23 @@ static uint32_t read32(void) xread(0, &v, 4); return ntohl(v); } - -static void write32(uint32_t v) -{ - v = htonl(v); - xwrite(1, &v, 4); -} - -static void f_write(const void* buf, int cnt) -{ - xwrite(1, buf, cnt); - add_bytes_to_chksum(&G.chksum_out, buf, cnt); -} - static void f_read(void* buf, int cnt) { xread(0, buf, cnt); - add_bytes_to_chksum(&G.chksum_in, buf, cnt); + add_bytes_to_chksum(buf, cnt); } - static int f_read8(void) { uint8_t v; f_read(&v, 1); return v; } - -static void f_write8(uint8_t v) -{ - f_write(&v, 1); -} - static unsigned f_read16(void) { uint16_t v; f_read(&v, 2); return ntohs(v); } - -static void f_write16(uint16_t v) -{ - v = htons(v); - f_write(&v, 2); -} - static uint32_t f_read32(void) { uint32_t v; @@ -626,34 +596,30 @@ static uint32_t f_read32(void) return ntohl(v); } -static void f_write32(uint32_t v) +static void write32(uint32_t v) { v = htonl(v); - f_write(&v, 4); + xwrite(1, &v, 4); } - -/**********************************************************************/ -static int lzo_get_method(header_t *h) +static void f_write(const void* buf, int cnt) { - /* check method */ - if (h->method == M_LZO1X_1) { - if (h->level == 0) - h->level = 3; - } else if (h->method == M_LZO1X_1_15) { - if (h->level == 0) - h->level = 1; - } else if (h->method == M_LZO1X_999) { - if (h->level == 0) - h->level = 9; - } else - return -1; /* not a LZO method */ - - /* check compression level */ - if (h->level < 1 || h->level > 9) - return 15; - - return 0; + xwrite(1, buf, cnt); + add_bytes_to_chksum(buf, cnt); } +//static void f_write8(uint8_t v) +//{ +// f_write(&v, 1); +//} +//static void f_write16(uint16_t v) +//{ +// v = htons(v); +// f_write(&v, 2); +//} +//static void f_write32(uint32_t v) +//{ +// v = htonl(v); +// f_write(&v, 4); +//} /**********************************************************************/ #define LZO_BLOCK_SIZE (256 * 1024l) @@ -697,9 +663,9 @@ static NOINLINE int lzo_compress(const header_t *h) break; /* compute checksum of uncompressed block */ - if (h->flags & F_ADLER32_D) + if (h->flags32 & F_ADLER32_D) d_adler32 = lzo_adler32(ADLER32_INIT_VALUE, b1, src_len); - if (h->flags & F_CRC32_D) + if (h->flags32 & F_CRC32_D) d_crc32 = lzo_crc32(CRC32_INIT_VALUE, b1, src_len); /* compress */ @@ -734,16 +700,16 @@ static NOINLINE int lzo_compress(const header_t *h) } /* write checksum of uncompressed block */ - if (h->flags & F_ADLER32_D) + if (h->flags32 & F_ADLER32_D) write32(d_adler32); - if (h->flags & F_CRC32_D) + if (h->flags32 & F_CRC32_D) write32(d_crc32); if (dst_len < src_len) { /* write checksum of compressed block */ - if (h->flags & F_ADLER32_C) + if (h->flags32 & F_ADLER32_C) write32(lzo_adler32(ADLER32_INIT_VALUE, b2, dst_len)); - if (h->flags & F_CRC32_C) + if (h->flags32 & F_CRC32_C) write32(lzo_crc32(CRC32_INIT_VALUE, b2, dst_len)); /* write compressed block data */ xwrite(1, b2, dst_len); @@ -777,7 +743,9 @@ static FAST_FUNC void lzo_check( /**********************************************************************/ // decompress a file /**********************************************************************/ -static NOINLINE int lzo_decompress(const header_t *h) +// used to have "const header_t *h" parameter, but since it uses +// only flags32 field, changed to receive only that. +static NOINLINE int lzo_decompress(uint32_t h_flags32) { unsigned block_size = LZO_BLOCK_SIZE; int r; @@ -822,16 +790,16 @@ static NOINLINE int lzo_decompress(const header_t *h) } /* read checksum of uncompressed block */ - if (h->flags & F_ADLER32_D) + if (h_flags32 & F_ADLER32_D) d_adler32 = read32(); - if (h->flags & F_CRC32_D) + if (h_flags32 & F_CRC32_D) d_crc32 = read32(); /* read checksum of compressed block */ if (src_len < dst_len) { - if (h->flags & F_ADLER32_C) + if (h_flags32 & F_ADLER32_C) c_adler32 = read32(); - if (h->flags & F_CRC32_C) + if (h_flags32 & F_CRC32_C) c_crc32 = read32(); } @@ -846,11 +814,11 @@ static NOINLINE int lzo_decompress(const header_t *h) if (!(option_mask32 & OPT_F)) { /* verify checksum of compressed block */ - if (h->flags & F_ADLER32_C) + if (h_flags32 & F_ADLER32_C) lzo_check(ADLER32_INIT_VALUE, b1, src_len, lzo_adler32, c_adler32); - if (h->flags & F_CRC32_C) + if (h_flags32 & F_CRC32_C) lzo_check(CRC32_INIT_VALUE, b1, src_len, lzo_crc32, c_crc32); @@ -873,11 +841,11 @@ static NOINLINE int lzo_decompress(const header_t *h) if (!(option_mask32 & OPT_F)) { /* verify checksum of uncompressed block */ - if (h->flags & F_ADLER32_D) + if (h_flags32 & F_ADLER32_D) lzo_check(ADLER32_INIT_VALUE, dst, dst_len, lzo_adler32, d_adler32); - if (h->flags & F_CRC32_D) + if (h_flags32 & F_CRC32_D) lzo_check(CRC32_INIT_VALUE, dst, dst_len, lzo_crc32, d_crc32); @@ -917,7 +885,7 @@ static NOINLINE int lzo_decompress(const header_t *h) * -00000020 00 00 2d 67 04 17 00 04 00 00 00 03 ed ec 9d 6d * +00000020 00 00 10 5f 00 c1 00 04 00 00 00 03 ed ec 9d 6d * ^^^^^^^^^^^ - * chksum_out + * chksum * The rest is identical. */ static const unsigned char lzop_magic[9] ALIGN1 = { @@ -936,114 +904,115 @@ static void check_magic(void) /**********************************************************************/ // lzop file header /**********************************************************************/ -static void write_header(const header_t *h) +static void write_header(header_t *h) { - int l; + char *end; xwrite(1, lzop_magic, sizeof(lzop_magic)); - init_chksum(&G.chksum_out); + init_chksum(); - f_write16(h->version); - f_write16(h->lib_version); - f_write16(h->version_needed_to_extract); - f_write8(h->method); - f_write8(h->level); - f_write32(h->flags); - f_write32(h->mode); - f_write32(h->mtime); - f_write32(h->gmtdiff); + /* Our caller leaves name zero-filled, so len == 0 */ + end = h->len_and_name+1 + 0; /* 0 is strlen(h->len_and_name+1) */ + /* Store length byte */ + /*h->len_and_name[0] = end - (h->len_and_name+1); - zero already */ - l = (int) strlen(h->name); - f_write8(l); - if (l) - f_write(h->name, l); + f_write(&h->version_be16, end - (char*)&h->version_be16); - f_write32(chksum_getresult(&G.chksum_out, h)); + h->flags32 = htonl(h->flags32); /* native endianness for lzo_compress() */ + + /*f_*/write32(chksum_getresult(h->flags32)); } static int read_header(header_t *h) { - int r; int l; uint32_t checksum; + unsigned h_version; + uint8_t h_method, h_level; - memset(h, 0, sizeof(*h)); - h->version_needed_to_extract = 0x0900; /* first lzop version */ - h->level = 0; - - init_chksum(&G.chksum_in); + init_chksum(); - h->version = f_read16(); - if (h->version < 0x0900) + /* As it stands now, only h->flags32 is used by our caller. + * Therefore we don't store many fields in h->field. + */ + h_version = f_read16(); + if (h_version < 0x0900) return 3; - h->lib_version = f_read16(); - if (h->version >= 0x0940) { - h->version_needed_to_extract = f_read16(); - if (h->version_needed_to_extract > LZOP_VERSION) + /* UNUSED h->lib_version_be16 = */ f_read16(); + if (h_version >= 0x0940) { + unsigned h_version_needed_to_extract = f_read16(); + if (h_version_needed_to_extract > LZOP_VERSION) return 16; - if (h->version_needed_to_extract < 0x0900) + if (h_version_needed_to_extract < 0x0900) /* first lzop version */ return 3; } - h->method = f_read8(); - if (h->version >= 0x0940) - h->level = f_read8(); - h->flags = f_read32(); - if (h->flags & F_H_FILTER) + + h_method = f_read8(); + if (h_method <= 0) + return 14; + h_level = 0; + if (h_version >= 0x0940) + h_level = f_read8(); + + /* former lzo_get_method(h): */ + if (h_method == M_LZO1X_1) { + if (h_level == 0) + h_level = 3; + } else if (h_method == M_LZO1X_1_15) { + if (h_level == 0) + h_level = 1; + } else if (h_method == M_LZO1X_999) { + if (h_level == 0) + h_level = 9; + } else + return -1; /* not a LZO method */ + /* check compression level */ + if (h_level < 1 || h_level > 9) + return 15; + + h->flags32 = f_read32(); + if (h->flags32 & F_H_FILTER) return 16; /* filter not supported */ - h->mode = f_read32(); - h->mtime = f_read32(); - if (h->version >= 0x0940) - h->gmtdiff = f_read32(); + /* check reserved flags */ + if (h->flags32 & F_RESERVED) + return -13; + + /* UNUSED h->mode = */ f_read32(); + /* UNUSED h->mtime = */ f_read32(); + if (h_version >= 0x0940) + /* UNUSED h->gmtdiff = */ f_read32(); l = f_read8(); + /* UNUSED h->len_and_name[0] = l; */ + /* UNUSED h->len_and_name[1+l] = 0; */ if (l > 0) - f_read(h->name, l); - h->name[l] = 0; + f_read(h->len_and_name+1, l); - checksum = chksum_getresult(&G.chksum_in, h); - h->header_checksum = f_read32(); - if (h->header_checksum != checksum) + checksum = chksum_getresult(h->flags32); + if (f_read32() != checksum) return 2; - if (h->method <= 0) - return 14; - r = lzo_get_method(h); - if (r != 0) - return r; - - /* check reserved flags */ - if (h->flags & F_RESERVED) - return -13; - /* skip extra field [not used yet] */ - if (h->flags & F_H_EXTRA_FIELD) { + if (h->flags32 & F_H_EXTRA_FIELD) { + uint32_t extra_field_len; + uint32_t extra_field_checksum; uint32_t k; /* note: the checksum also covers the length */ - init_chksum(&G.chksum_in); - h->extra_field_len = f_read32(); - for (k = 0; k < h->extra_field_len; k++) + init_chksum(); + extra_field_len = f_read32(); + for (k = 0; k < extra_field_len; k++) f_read8(); - checksum = chksum_getresult(&G.chksum_in, h); - h->extra_field_checksum = f_read32(); - if (h->extra_field_checksum != checksum) + checksum = chksum_getresult(h->flags32); + extra_field_checksum = f_read32(); + if (extra_field_checksum != checksum) return 3; } return 0; } -static void p_header(header_t *h) -{ - int r; - - r = read_header(h); - if (r == 0) - return; - bb_error_msg_and_die("header_error %d", r); -} - /**********************************************************************/ // compress /**********************************************************************/ @@ -1082,18 +1051,21 @@ static int do_lzo_compress(void) lzo_set_method(h); - h->version = (LZOP_VERSION & 0xffff); - h->version_needed_to_extract = 0x0940; - h->lib_version = lzo_version() & 0xffff; + h->version_be16 = htons(LZOP_VERSION & 0xffff); + h->version_needed_to_extract_be16 = htons(0x0940); + h->lib_version_be16 = htons(lzo_version() & 0xffff); - h->flags = (F_OS & F_OS_MASK) | (F_CS & F_CS_MASK); + h->flags32 = htonl((F_OS & F_OS_MASK) | (F_CS & F_CS_MASK)); if (!(option_mask32 & OPT_F) || h->method == M_LZO1X_999) { - h->flags |= F_ADLER32_D; + h->flags32 |= htonl(F_ADLER32_D); if (option_mask32 & OPT_C) - h->flags |= F_ADLER32_C; + h->flags32 |= htonl(F_ADLER32_C); } + + /* write_header() also converts h->flags32 to native endianness */ write_header(h); + return lzo_compress(h); #undef h } @@ -1103,11 +1075,14 @@ static int do_lzo_compress(void) /**********************************************************************/ static int do_lzo_decompress(void) { + int r; header_t header; check_magic(); - p_header(&header); - return lzo_decompress(&header); + r = read_header(&header); + if (r != 0) + bb_error_msg_and_die("header_error %d", r); + return lzo_decompress(header.flags32); } static char* FAST_FUNC make_new_name_lzop(char *filename, const char *expected_ext UNUSED_PARAM) @@ -1132,6 +1107,8 @@ static IF_DESKTOP(long long) int FAST_FUNC pack_lzop(transformer_state_t *xstate int lzop_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int lzop_main(int argc UNUSED_PARAM, char **argv) { + INIT_G(); + getopt32(argv, OPTION_STRING); argv += optind; /* -U is "anti -k", invert bit for bbunpack(): */ -- 2.25.1