Differential D1638 Diff 4547 src/script/interpreter.cpp

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src/script/interpreter.cpp

Show All 23 Lines	for (size_t i = 0; i < vch.size(); i++) {
return false;		return false;
}		}
return true;		return true;
}		}
}		}
return false;		return false;
}		}

		inline uint8_t make_rshift_mask(size_t n) {
		static uint8_t mask[] = {0xFF, 0xFE, 0xFC, 0xF8, 0xF0, 0xE0, 0xC0, 0x80};
		return mask[n];
		}

		inline uint8_t make_lshift_mask(size_t n) {
		static uint8_t mask[] = {0xFF, 0x7F, 0x3F, 0x1F, 0x0F, 0x07, 0x03, 0x01};
		return mask[n];
		}

		static valtype RShift(const valtype &x, int n) {
		int bit_shift_left = n % 8;
		int byte_shift_left = n / 8;

		uint8_t mask = make_rshift_mask(bit_shift_left);
		uint8_t overflow_mask = ~mask;

		valtype result(x.size(), 0x00);
		for (int i = x.size() - 1; i >= 0; i--) {
		int k = i - byte_shift_left;
		if (k >= 0) {
		uint8_t val = (x[i] & mask);
		val >>= bit_shift_left;
		result[k] \|= val;
		}
		if (k - 1 >= 0) {
		uint8_t carryval = (x[i] & overflow_mask);
		carryval <<= 8 - bit_shift_left;
		result[k - 1] \|= carryval;
		}
		}
		return result;
		}

		static valtype LShift(const valtype &x, int n) {
		int bit_shift_right = n % 8;
		int byte_shift_right = n / 8;

		uint8_t mask = make_lshift_mask(bit_shift_right);
		uint8_t overflow_mask = ~mask;

		valtype result(x.size(), 0x00);
		for (int i = 0; i < (int)x.size(); i++) {
		int k = i + byte_shift_right;
		if (k < (int)x.size()) {
		uint8_t val = (x[i] & mask);
		val <<= bit_shift_right;
		result[k] \|= val;
		}
		if (k + 1 < (int)x.size()) {
		uint8_t carryval = (x[i] & overflow_mask);
		carryval >>= 8 - bit_shift_right;
		result[k + 1] \|= carryval;
		}
		}
		return result;
		}

/**		/**
* Script is a stack machine (like Forth) that evaluates a predicate		* Script is a stack machine (like Forth) that evaluates a predicate
* returning a bool indicating valid or not. There are no loops.		* returning a bool indicating valid or not. There are no loops.
*/		*/
#define stacktop(i) (stack.at(stack.size() + (i)))		#define stacktop(i) (stack.at(stack.size() + (i)))
#define altstacktop(i) (altstack.at(altstack.size() + (i)))		#define altstacktop(i) (altstack.at(altstack.size() + (i)))
static inline void popstack(std::vector<valtype> &stack) {		static inline void popstack(std::vector<valtype> &stack) {
if (stack.empty()) {		if (stack.empty()) {
▲ Show 20 Lines • Show All 49 Lines • ▼ Show 20 Lines	if (fEnabledOpCodesMagnetic) {
switch (opcode) {		switch (opcode) {
case OP_INVERT:		case OP_INVERT:
return true;		return true;

case OP_MUL:		case OP_MUL:
return true;		return true;

case OP_LSHIFT:		case OP_LSHIFT:
return true;		return false;

case OP_RSHIFT:		case OP_RSHIFT:
return true;		return false;

default:		default:
break;		break;
}		}
}		}

switch (opcode) {		switch (opcode) {
case OP_INVERT:		case OP_INVERT:
▲ Show 20 Lines • Show All 1,120 Lines • ▼ Show 20 Lines

// The resulting number must be a valid number.		// The resulting number must be a valid number.
if (!CScriptNum::IsMinimallyEncoded(n)) {		if (!CScriptNum::IsMinimallyEncoded(n)) {
return set_error(serror,		return set_error(serror,
SCRIPT_ERR_INVALID_NUMBER_RANGE);		SCRIPT_ERR_INVALID_NUMBER_RANGE);
}		}
} break;		} break;

		case OP_LSHIFT: {
		// (x n -- out)
		if (stack.size() < 2) {
		return set_error(
		serror, SCRIPT_ERR_INVALID_STACK_OPERATION);
		}

		const valtype x = stacktop(-2);
		CScriptNum n(stacktop(-1), fRequireMinimal);
		if (n < 0) {
		return set_error(serror,
		SCRIPT_ERR_INVALID_NUMBER_RANGE);
		}

		popstack(stack);
		popstack(stack);
		stack.push_back(LShift(x, n.getint()));
		} break;

		case OP_RSHIFT: {
		// (x n -- out)
		if (stack.size() < 2) {
		return set_error(
		serror, SCRIPT_ERR_INVALID_STACK_OPERATION);
		}

		const valtype x = stacktop(-2);
		CScriptNum n(stacktop(-1), fRequireMinimal);
		if (n < 0) {
		return set_error(serror,
		SCRIPT_ERR_INVALID_NUMBER_RANGE);
		}

		popstack(stack);
		popstack(stack);
		stack.push_back(RShift(x, n.getint()));
		} break;

default:		default:
return set_error(serror, SCRIPT_ERR_BAD_OPCODE);		return set_error(serror, SCRIPT_ERR_BAD_OPCODE);
}		}
}		}

// Size limits		// Size limits
if (stack.size() + altstack.size() > 1000) {		if (stack.size() + altstack.size() > 1000) {
return set_error(serror, SCRIPT_ERR_STACK_SIZE);		return set_error(serror, SCRIPT_ERR_STACK_SIZE);
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