radare2/libr/reg/value.c

/* radare - LGPL - Copyright 2009-2015 - pancake */

#include <r_reg.h>
#include <r_util.h>

R_API ut64 r_reg_get_value(RReg *reg, RRegItem *item) {
	RRegSet *regset;
	ut32 v32;
	ut16 v16;
	ut8 v8;
	int off;
	ut64 ret = 0LL;
	if (!reg || !item)
		return 0LL;
	off = BITS2BYTES (item->offset);
	regset = &reg->regset[item->type];
#if 0
	eprintf ("GET sz=%d off %d  off = %d %d\n",
		item->size, off, item->offset, (item->offset/8));
#endif
	switch (item->size) {
	case 80: // long double
		ret = (ut64)r_reg_get_double (reg, item);
		eprintf ("precission loss\n");
		break;
	case 1:
		ret = (regset->arena->bytes[item->offset/8] & \
			(1<<(item->offset%8)))?1:0;
		break;
	case 8:
		if (regset->arena->size-off-1>=0) {
			memcpy (&v8, regset->arena->bytes+off, 1);
			ret = v8;
		}
		break;
	case 16:
		if (regset->arena->size-off-2>=0) {
			r_mem_copyendian ((ut8*)&v16, (ut8*)regset->arena->bytes+off, 2, !reg->big_endian);
			ret = v16;
		}
		break;
	case 32:
		if (off+4<=regset->arena->size) {
			r_mem_copyendian ((ut8*)&v32, (ut8*)regset->arena->bytes+off, 4, !reg->big_endian);
			ret = v32;
		} else eprintf ("r_reg_get_value: 32bit oob read %d\n", off);
		break;
	case 64:
		if (regset->arena->bytes && (off+8<=regset->arena->size))
			r_mem_copyendian ((ut8*)&ret, (ut8*)regset->arena->bytes+off, 8, !reg->big_endian);
		else eprintf ("r_reg_get_value: null or oob arena for current regset\n");
		break;
	default:
		eprintf ("r_reg_get_value: Bit size %d not supported\n", item->size);
		break;
	}
	return ret;
}

R_API int r_reg_set_value(RReg *reg, RRegItem *item, ut64 value) {
	ut64 v64;
	ut32 v32;
	ut16 v16;
	ut8 v8, *src;

	if (!item) {
		eprintf ("r_reg_set_value: item is NULL\n");
		return R_FALSE;
	}
	switch (item->size) {
	case 64: r_mem_copyendian ( (ut8*)&v64, (ut8*)&value, 8, !reg->big_endian); src = (ut8*)&v64; break;
	case 32: r_mem_copyendian ( (ut8*)&v32, (ut8*)&value, 4, !reg->big_endian); src = (ut8*)&v32; break;
	case 16: r_mem_copyendian ( (ut8*)&v16, (ut8*)&value, 2, !reg->big_endian); src = (ut8*)&v16; break;
	case 8:  v8  = (ut8)value;  src = (ut8*)&v8;  break;
	case 1:
		if (value) {
			ut8 * buf = reg->regset[item->type].arena->bytes + (item->offset/8);
			int bit = (item->offset%8);
			ut8 mask = (1<<bit);
			buf[0] = (buf[0] &(0xff^mask)) | mask;
		} else {
			ut8 * buf = reg->regset[item->type].arena->bytes + (item->offset/8);
			int bit = item->offset % 8;
			ut8 mask = 0xff ^ (1 << bit);
			buf[0] = (buf[0] & mask) | 0;
		}
		return R_TRUE;
	default:
		eprintf ("r_reg_set_value: Bit size %d not supported\n", item->size);
		return R_FALSE;
	}
	if (reg->regset[item->type].arena->size - BITS2BYTES (item->offset) - BITS2BYTES(item->size)>=0) {
		r_mem_copybits (reg->regset[item->type].arena->bytes+
				BITS2BYTES (item->offset), src, item->size);
		return R_TRUE;
	}
	eprintf ("r_reg_set_value: Cannot set %s to 0x%"PFMT64x"\n", item->name, value);
	return R_FALSE;
}

R_API ut64 r_reg_set_bvalue(RReg *reg, RRegItem *item, const char *str) {
	ut64 num = UT64_MAX;
	if (item && item->flags && str) {
		num = r_str_bits_from_string (str, item->flags);
		if (num == UT64_MAX) 
			num = r_num_math (NULL, str);
		r_reg_set_value (reg, item, num);
	}
	return num;
}

// experimental new notation
#undef HEAP
#define HEAP 

R_API HEAP char *r_reg_get_bvalue(RReg *reg, RRegItem *item) {
	char *out = NULL;
	if (reg && item && item->flags) {
		out = malloc (strlen (item->flags)+1);
		if (out) {
			ut64 num = r_reg_get_value (reg, item);
			r_str_bits (out, (ut8*)&num,
				strlen (item->flags) * 8, item->flags);
		}
	}
	return out;
}

/* packed registers */
// packbits can be 8, 16, 32 or 64
// result value is always casted into ut64
// TODO: use item->packed_size 
R_API ut64 r_reg_get_pack(RReg *reg, RRegItem *item, int packidx, int packbits) {
	int packbytes, packmod;
	ut64 ret = 0LL;
	RRegSet *regset;
	int off;
	if (!reg || !item)
		return 0LL;
	if (packbits<1) {
		packbits = item->packed_size;
	}
	packbytes = packbits / 8;
	packmod = packbits % 8;
	if (packmod) {
		eprintf ("Invalid bit size for packet register\n");
		return 0LL;
	}
	off = BITS2BYTES (item->offset);
	regset = &reg->regset[item->type];
	off += (packidx * packbytes);
	if (regset->arena->size - off - 1 >= 0) {
		memcpy (&ret, regset->arena->bytes + off, packbytes);
	}
	return ret;
}

R_API int r_reg_set_pack(RReg *reg, RRegItem *item, int packidx, int packbits, ut64 val) {
	int packbytes, packmod;
	int off = item->offset;

	if (!reg || !item) {
		eprintf ("r_reg_set_value: item is NULL\n");
		return R_FALSE;
	}
	if (packbits<1) {
		packbits = item->packed_size;
	}
	packbytes = packbits / 8;
	packmod = packbits % 8;
	if (packidx * packbits > item->size) {
		eprintf ("Packed index is beyond the register size\n");
		return R_FALSE;
	}
	if (packmod) {
		eprintf ("Invalid bit size for packet register\n");
		return R_FALSE;
	}
	if (reg->regset[item->type].arena->size - BITS2BYTES (off) - BITS2BYTES(packbytes) >= 0) {
		r_mem_copybits (reg->regset[item->type].arena->bytes+
				BITS2BYTES (off), (ut8*)&val, packbytes);
		return R_TRUE;
	}
	eprintf ("r_reg_set_value: Cannot set %s to 0x%"PFMT64x"\n", item->name, val);
	return R_FALSE;
}