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46 lines
1.4 KiB
C
46 lines
1.4 KiB
C
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/* deflate_huff.c -- compress data using huffman encoding only strategy
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*
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* Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
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* For conditions of distribution and use, see copyright notice in zlib.h
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*/
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#include "zbuild.h"
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#include "deflate.h"
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#include "deflate_p.h"
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#include "functable.h"
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/* ===========================================================================
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* For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table.
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* (It will be regenerated if this run of deflate switches away from Huffman.)
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*/
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Z_INTERNAL block_state deflate_huff(deflate_state *s, int flush) {
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int bflush = 0; /* set if current block must be flushed */
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for (;;) {
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/* Make sure that we have a literal to write. */
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if (s->lookahead == 0) {
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PREFIX(fill_window)(s);
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if (s->lookahead == 0) {
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if (flush == Z_NO_FLUSH)
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return need_more;
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break; /* flush the current block */
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}
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}
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/* Output a literal byte */
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bflush = zng_tr_tally_lit(s, s->window[s->strstart]);
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s->lookahead--;
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s->strstart++;
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if (bflush)
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FLUSH_BLOCK(s, 0);
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}
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s->insert = 0;
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if (flush == Z_FINISH) {
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FLUSH_BLOCK(s, 1);
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return finish_done;
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}
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if (s->sym_next)
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FLUSH_BLOCK(s, 0);
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return block_done;
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}
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