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author | Matthias Klose <doko@ubuntu.com> | 2012-11-16 18:35:05 +0000 |
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committer | Matthias Klose <doko@gcc.gnu.org> | 2012-11-16 18:35:05 +0000 |
commit | 9acb8ddf3e7cf312de229eae11e0a1df29548ec9 (patch) | |
tree | 134aeb9aadb88e8719595edaaa40522b99d2a56a /zlib/trees.c | |
parent | 50605a7f19869692a6c29cead0a1366a420e0e65 (diff) | |
download | gcc-9acb8ddf3e7cf312de229eae11e0a1df29548ec9.zip gcc-9acb8ddf3e7cf312de229eae11e0a1df29548ec9.tar.gz gcc-9acb8ddf3e7cf312de229eae11e0a1df29548ec9.tar.bz2 |
2012-11-16 Matthias Klose <doko@ubuntu.com>
* Imported zlib 1.2.7; merged local changes.
From-SVN: r193574
Diffstat (limited to 'zlib/trees.c')
-rw-r--r-- | zlib/trees.c | 40 |
1 files changed, 10 insertions, 30 deletions
diff --git a/zlib/trees.c b/zlib/trees.c index 049a91a..cd0af2d 100644 --- a/zlib/trees.c +++ b/zlib/trees.c @@ -1,5 +1,5 @@ /* trees.c -- output deflated data using Huffman coding - * Copyright (C) 1995-2010 Jean-loup Gailly + * Copyright (C) 1995-2012 Jean-loup Gailly * detect_data_type() function provided freely by Cosmin Truta, 2006 * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -74,11 +74,6 @@ local const uch bl_order[BL_CODES] * probability, to avoid transmitting the lengths for unused bit length codes. */ -#define Buf_size (8 * 2*sizeof(char)) -/* Number of bits used within bi_buf. (bi_buf might be implemented on - * more than 16 bits on some systems.) - */ - /* =========================================================================== * Local data. These are initialized only once. */ @@ -399,7 +394,6 @@ void ZLIB_INTERNAL _tr_init(s) s->bi_buf = 0; s->bi_valid = 0; - s->last_eob_len = 8; /* enough lookahead for inflate */ #ifdef DEBUG s->compressed_len = 0L; s->bits_sent = 0L; @@ -883,15 +877,17 @@ void ZLIB_INTERNAL _tr_stored_block(s, buf, stored_len, last) } /* =========================================================================== + * Flush the bits in the bit buffer to pending output (leaves at most 7 bits) + */ +void ZLIB_INTERNAL _tr_flush_bits(s) + deflate_state *s; +{ + bi_flush(s); +} + +/* =========================================================================== * Send one empty static block to give enough lookahead for inflate. * This takes 10 bits, of which 7 may remain in the bit buffer. - * The current inflate code requires 9 bits of lookahead. If the - * last two codes for the previous block (real code plus EOB) were coded - * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode - * the last real code. In this case we send two empty static blocks instead - * of one. (There are no problems if the previous block is stored or fixed.) - * To simplify the code, we assume the worst case of last real code encoded - * on one bit only. */ void ZLIB_INTERNAL _tr_align(s) deflate_state *s; @@ -902,20 +898,6 @@ void ZLIB_INTERNAL _tr_align(s) s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ #endif bi_flush(s); - /* Of the 10 bits for the empty block, we have already sent - * (10 - bi_valid) bits. The lookahead for the last real code (before - * the EOB of the previous block) was thus at least one plus the length - * of the EOB plus what we have just sent of the empty static block. - */ - if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { - send_bits(s, STATIC_TREES<<1, 3); - send_code(s, END_BLOCK, static_ltree); -#ifdef DEBUG - s->compressed_len += 10L; -#endif - bi_flush(s); - } - s->last_eob_len = 7; } /* =========================================================================== @@ -1118,7 +1100,6 @@ local void compress_block(s, ltree, dtree) } while (lx < s->last_lit); send_code(s, END_BLOCK, ltree); - s->last_eob_len = ltree[END_BLOCK].Len; } /* =========================================================================== @@ -1226,7 +1207,6 @@ local void copy_block(s, buf, len, header) int header; /* true if block header must be written */ { bi_windup(s); /* align on byte boundary */ - s->last_eob_len = 8; /* enough lookahead for inflate */ if (header) { put_short(s, (ush)len); |