1  /* extracted from gdb sources */
       2  
       3  typedef unsigned long long CORE_ADDR;
       4  
       5  struct blockvector;
       6  
       7  struct symtab {
       8    struct blockvector *blockvector;
       9  };
      10  
      11  struct sec {
      12    void *unused;
      13  };
      14  
      15  struct symbol {
      16    int len;
      17    char *name;
      18  };
      19  
      20  struct block {
      21  	CORE_ADDR startaddr, endaddr;
      22  	struct symbol *function;
      23  	struct block *superblock;
      24  	unsigned char gcc_compile_flag;
      25  	int nsyms;
      26  	struct symbol syms[1];
      27  };
      28  
      29  struct blockvector {
      30  	int nblocks;
      31  	struct block *block[2];
      32  };
      33  
      34  struct blockvector *blockvector_for_pc_sect(register CORE_ADDR pc,
      35  					    struct symtab *symtab)
      36  {
      37    register struct block *b;
      38    register int bot, top, half;
      39    struct blockvector *bl;
      40  
      41    bl = symtab->blockvector;
      42    b = bl->block[0];
      43  
      44    bot = 0;
      45    top = bl->nblocks;
      46  
      47    while (top - bot > 1)
      48      {
      49        half = (top - bot + 1) >> 1;
      50        b = bl->block[bot + half];
      51        if (b->startaddr <= pc)
      52  	bot += half;
      53        else
      54  	top = bot + half;
      55      }
      56  
      57    while (bot >= 0)
      58      {
      59        b = bl->block[bot];
      60        if (b->endaddr > pc)
      61  	{
      62  	  return bl;
      63  	}
      64        bot--;
      65      }
      66    return 0;
      67  }
      68  
      69  int main(void)
      70  {
      71    struct block a = { 0, 0x10000, 0, 0, 1, 20 };
      72    struct block b = { 0x10000, 0x20000, 0, 0, 1, 20 };
      73    struct blockvector bv = { 2, { &a, &b } };
      74    struct symtab s = { &bv };
      75  
      76    struct blockvector *ret;
      77  
      78    ret = blockvector_for_pc_sect(0x500, &s);
      79  
      80    return 0;
      81  }