1  ///////////////////////////////////////////////////////////////////////////////
       2  //
       3  /// \file       fastpos_tablegen.c
       4  /// \brief      Generates the lzma_fastpos[] lookup table
       5  ///
       6  //  Authors:    Igor Pavlov
       7  //              Lasse Collin
       8  //
       9  //  This file has been put into the public domain.
      10  //  You can do whatever you want with this file.
      11  //
      12  ///////////////////////////////////////////////////////////////////////////////
      13  
      14  #include <inttypes.h>
      15  #include <stdio.h>
      16  
      17  #define lzma_attr_visibility_hidden
      18  #include "fastpos.h"
      19  
      20  
      21  int
      22  main(void)
      23  {
      24  	uint8_t fastpos[1 << FASTPOS_BITS];
      25  
      26  	const uint8_t fast_slots = 2 * FASTPOS_BITS;
      27  	uint32_t c = 2;
      28  
      29  	fastpos[0] = 0;
      30  	fastpos[1] = 1;
      31  
      32  	for (uint8_t slot_fast = 2; slot_fast < fast_slots; ++slot_fast) {
      33  		const uint32_t k = 1 << ((slot_fast >> 1) - 1);
      34  		for (uint32_t j = 0; j < k; ++j, ++c)
      35  			fastpos[c] = slot_fast;
      36  	}
      37  
      38  	printf("/* This file has been automatically generated "
      39  			"by fastpos_tablegen.c. */\n\n"
      40  			"#include \"common.h\"\n"
      41  			"#include \"fastpos.h\"\n\n"
      42  			"const uint8_t lzma_fastpos[1 << FASTPOS_BITS] = {");
      43  
      44  	for (size_t i = 0; i < (1 << FASTPOS_BITS); ++i) {
      45  		if (i % 16 == 0)
      46  			printf("\n\t");
      47  
      48  		printf("%3u", (unsigned int)(fastpos[i]));
      49  
      50  		if (i != (1 << FASTPOS_BITS) - 1)
      51  			printf(",");
      52  	}
      53  
      54  	printf("\n};\n");
      55  
      56  	return 0;
      57  }