/* * decinit.c * * Initialisation routines for LZX decoder */ #include "decoder.h" #include #pragma intrinsic(memset) /* * Allocate memory for decompression */ bool NEAR allocate_decompression_memory(t_decoder_context *context) { ulong pos_start; context->dec_num_position_slots = 4; pos_start = 4; while (1) { pos_start += 1L << dec_extra_bits[context->dec_num_position_slots]; context->dec_num_position_slots++; if (pos_start >= context->dec_window_size) break; } if (!(context->dec_mem_window = (byte *) context->dec_malloc( context->dec_mallochandle, context->dec_window_size+(MAX_MATCH+4)))) return false; return true; } /* * Set/reset decoder trees to initial state */ void NEAR reset_decoder_trees(t_decoder_context *context) { memset(context->dec_main_tree_len, 0, MAIN_TREE_ELEMENTS); memset(context->dec_main_tree_prev_len, 0, MAIN_TREE_ELEMENTS); memset(context->dec_secondary_length_tree_len, 0, NUM_SECONDARY_LENGTHS); memset(context->dec_secondary_length_tree_prev_len, 0, NUM_SECONDARY_LENGTHS); } /* * Miscellaneous state initialisations */ void NEAR decoder_misc_init(t_decoder_context *context) { context->dec_last_matchpos_offset[0] = 1; context->dec_last_matchpos_offset[1] = 1; context->dec_last_matchpos_offset[2] = 1; context->dec_bufpos = 0; context->dec_position_at_start = 0; context->dec_decoder_state = DEC_STATE_START_NEW_BLOCK; context->dec_block_size = 0; /* so that initialise_decoder_bitbuf() will succeed */ context->dec_block_type = BLOCKTYPE_INVALID; context->dec_first_time_this_group = true; context->dec_current_file_size = 0; context->dec_error_condition = false; }