69 lines
1.5 KiB
C
69 lines
1.5 KiB
C
/*
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* d16uncmp.c
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*
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* Decoding uncompressed blocks
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*/
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#include "decoder.h"
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int NEAR decode_uncompressed_block(
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t_decoder_context * context,
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long bufpos,
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int amount_to_decode /* yes, it will equal 32768 */
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)
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{
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byte *p;
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p = context->dec_input_curpos;
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/*
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* Since this is a DO loop, we predecrement amount_to_decode,
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* so it's ok for it to come in with a value of 32768
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*/
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do
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{
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if (p >= context->dec_end_input_pos)
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return -1;
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context->DComp_Token_Literal(
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context,
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*p++
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);
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} while (--amount_to_decode > 0);
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context->dec_input_curpos = p;
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return 0;
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}
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bool NEAR handle_beginning_of_uncompressed_block(t_decoder_context *context)
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{
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int i;
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/*
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* we want to read the 16 bits already in bitbuf, so backtrack
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* the input pointer by 2 bytes
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*/
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context->dec_input_curpos -= 2;
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if (context->dec_input_curpos + 4 >= context->dec_end_input_pos)
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return false;
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/*
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* update LRU repeated offset list
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*/
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for (i = 0; i < NUM_REPEATED_OFFSETS; i++)
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{
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context->dec_last_matchpos_offset[i] =
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((ulong) *( (byte *) context->dec_input_curpos) ) |
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((ulong) *( ((byte *) context->dec_input_curpos) + 1) << 8) |
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((ulong) *( ((byte *) context->dec_input_curpos) + 2) << 16) |
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((ulong) *( ((byte *) context->dec_input_curpos) + 3) << 24);
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context->dec_input_curpos += 4; /* increment by 4 bytes */
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}
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return true;
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}
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