radare2/libr/anal/bb.c

120 lines
3.4 KiB
C

/* radare - LGPL - Copyright 2010-2022 - pancake, nibble */
#include <r_anal.h>
#include <r_util.h>
#include <r_list.h>
#include <limits.h>
typedef struct {
ut64 addr;
RAnalBlock *ret;
} BBFromOffsetJmpmidCtx;
static bool bb_from_offset_jmpmid_cb(RAnalBlock *block, void *user) {
BBFromOffsetJmpmidCtx *ctx = user;
// If an instruction starts exactly at the search addr, return that block immediately
if (r_anal_block_op_starts_at (block, ctx->addr)) {
ctx->ret = block;
return false;
}
// else search the closest one
if (!ctx->ret || ctx->ret->addr < block->addr) {
ctx->ret = block;
}
return true;
}
static bool bb_from_offset_first_cb(RAnalBlock *block, void *user) {
RAnalBlock **ret = user;
*ret = block;
return false;
}
R_API RAnalBlock *r_anal_bb_from_offset(RAnal *anal, ut64 off) {
if (anal->opt.jmpmid && r_anal_is_aligned (anal, off)) {
BBFromOffsetJmpmidCtx ctx = { off, NULL };
r_anal_blocks_foreach_in (anal, off, bb_from_offset_jmpmid_cb, &ctx);
return ctx.ret;
}
RAnalBlock *ret = NULL;
r_anal_blocks_foreach_in (anal, off, bb_from_offset_first_cb, &ret);
return ret;
}
/* returns the offset of the i-th instruction in the basicblock bb.
* If the index of the instruction is not valid, it returns UT16_MAX */
R_API ut16 r_anal_bb_offset_inst(const RAnalBlock *bb, int i) {
if (i < 0 || i >= bb->ninstr) {
return UT16_MAX;
}
return (i > 0 && (i - 1) < bb->op_pos_size)? bb->op_pos[i - 1]: 0;
}
/* returns the address of the i-th instruction in the basicblock bb.
* If the index of the instruction is not valid, it returns UT64_MAX */
R_API ut64 r_anal_bb_opaddr_i(RAnalBlock *bb, int i) {
ut16 offset = r_anal_bb_offset_inst (bb, i);
if (offset == UT16_MAX) {
return UT64_MAX;
}
return bb->addr + offset;
}
/* set the offset of the i-th instruction in the basicblock bb */
R_API bool r_anal_bb_set_offset(RAnalBlock *bb, int i, ut16 v) {
// the offset 0 of the instruction 0 is not stored because always 0
if (i > 0 && v > 0) {
if (i >= bb->op_pos_size) {
int new_pos_size = i * 2;
ut16 *tmp_op_pos = realloc (bb->op_pos, new_pos_size * sizeof (*bb->op_pos));
if (!tmp_op_pos) {
return false;
}
bb->op_pos_size = new_pos_size;
bb->op_pos = tmp_op_pos;
}
bb->op_pos[i - 1] = v;
return true;
}
return true;
}
/* returns the address of the instruction that occupies a given offset.
* If the offset is not part of the given basicblock, UT64_MAX is returned. */
R_API ut64 r_anal_bb_opaddr_at(RAnalBlock *bb, ut64 off) {
ut16 delta, delta_off, last_delta;
int i;
if (!r_anal_block_contains (bb, off)) {
return UT64_MAX;
}
last_delta = 0;
delta_off = off - bb->addr;
for (i = 0; i < bb->ninstr; i++) {
delta = r_anal_bb_offset_inst (bb, i);
if (delta > delta_off) {
return bb->addr + last_delta;
}
last_delta = delta;
}
return bb->addr + last_delta;
}
// returns the size of the i-th instruction in a basicblock
R_API ut64 r_anal_bb_size_i(RAnalBlock *bb, int i) {
if (i < 0 || i >= bb->ninstr) {
return UT64_MAX;
}
ut16 idx_cur = r_anal_bb_offset_inst (bb, i);
ut16 idx_next = r_anal_bb_offset_inst (bb, i + 1);
return idx_next != UT16_MAX? idx_next - idx_cur: bb->size - idx_cur;
}
/* returns the address of the basicblock that contains addr or UT64_MAX if
* there is no such basic block */
R_API ut64 r_anal_get_bbaddr(RAnal *anal, ut64 addr) {
RAnalBlock *bb = r_anal_bb_from_offset (anal, addr);
return bb? bb->addr: UT64_MAX;
}