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