/* extracted from gdb sources */

typedef unsigned long long CORE_ADDR;

struct blockvector;

struct symtab {
    struct blockvector *blockvector;
};

struct sec {
    void *unused;
};

struct symbol {
    int len;
    char *name;
};

struct block {
    CORE_ADDR startaddr, endaddr;
    struct symbol *function;
    struct block *superblock;
    unsigned char gcc_compile_flag;
    int nsyms;
    struct symbol syms[1];
};

struct blockvector {
    int nblocks;
    struct block *block[2];
};

struct blockvector *blockvector_for_pc_sect(register CORE_ADDR pc,
                                            struct symtab *symtab) {
    register struct block *b;
    register int bot, top, half;
    struct blockvector *bl;

    bl = symtab->blockvector;
    b = bl->block[0];

    bot = 0;
    top = bl->nblocks;

    while (top - bot > 1) {
        half = (top - bot + 1) >> 1;
        b = bl->block[bot + half];
        if (b->startaddr <= pc)
            bot += half;
        else
            top = bot + half;
    }

    while (bot >= 0) {
        b = bl->block[bot];
        if (b->endaddr > pc) {
            return bl;
        }
        bot--;
    }
    return 0;
}

int main(void) {
    struct block a = {0, 0x10000, 0, 0, 1, 20};
    struct block b = {0x10000, 0x20000, 0, 0, 1, 20};
    struct blockvector bv = {2, {&a, &b}};
    struct symtab s = {&bv};

    struct blockvector *ret;

    ret = blockvector_for_pc_sect(0x500, &s);

    return 0;
}
