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Diffstat (limited to 'cli/vendor/github.com/ethereum/go-ethereum/common/math/integer.go')
-rw-r--r--cli/vendor/github.com/ethereum/go-ethereum/common/math/integer.go98
1 files changed, 98 insertions, 0 deletions
diff --git a/cli/vendor/github.com/ethereum/go-ethereum/common/math/integer.go b/cli/vendor/github.com/ethereum/go-ethereum/common/math/integer.go
new file mode 100644
index 0000000..50d3eba
--- /dev/null
+++ b/cli/vendor/github.com/ethereum/go-ethereum/common/math/integer.go
@@ -0,0 +1,98 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package math
+
+import (
+ "fmt"
+ "math/bits"
+ "strconv"
+)
+
+// Integer limit values.
+const (
+ MaxInt8 = 1<<7 - 1
+ MinInt8 = -1 << 7
+ MaxInt16 = 1<<15 - 1
+ MinInt16 = -1 << 15
+ MaxInt32 = 1<<31 - 1
+ MinInt32 = -1 << 31
+ MaxInt64 = 1<<63 - 1
+ MinInt64 = -1 << 63
+ MaxUint8 = 1<<8 - 1
+ MaxUint16 = 1<<16 - 1
+ MaxUint32 = 1<<32 - 1
+ MaxUint64 = 1<<64 - 1
+)
+
+// HexOrDecimal64 marshals uint64 as hex or decimal.
+type HexOrDecimal64 uint64
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (i *HexOrDecimal64) UnmarshalText(input []byte) error {
+ int, ok := ParseUint64(string(input))
+ if !ok {
+ return fmt.Errorf("invalid hex or decimal integer %q", input)
+ }
+ *i = HexOrDecimal64(int)
+ return nil
+}
+
+// MarshalText implements encoding.TextMarshaler.
+func (i HexOrDecimal64) MarshalText() ([]byte, error) {
+ return []byte(fmt.Sprintf("%#x", uint64(i))), nil
+}
+
+// ParseUint64 parses s as an integer in decimal or hexadecimal syntax.
+// Leading zeros are accepted. The empty string parses as zero.
+func ParseUint64(s string) (uint64, bool) {
+ if s == "" {
+ return 0, true
+ }
+ if len(s) >= 2 && (s[:2] == "0x" || s[:2] == "0X") {
+ v, err := strconv.ParseUint(s[2:], 16, 64)
+ return v, err == nil
+ }
+ v, err := strconv.ParseUint(s, 10, 64)
+ return v, err == nil
+}
+
+// MustParseUint64 parses s as an integer and panics if the string is invalid.
+func MustParseUint64(s string) uint64 {
+ v, ok := ParseUint64(s)
+ if !ok {
+ panic("invalid unsigned 64 bit integer: " + s)
+ }
+ return v
+}
+
+// SafeSub returns x-y and checks for overflow.
+func SafeSub(x, y uint64) (uint64, bool) {
+ diff, borrowOut := bits.Sub64(x, y, 0)
+ return diff, borrowOut != 0
+}
+
+// SafeAdd returns x+y and checks for overflow.
+func SafeAdd(x, y uint64) (uint64, bool) {
+ sum, carryOut := bits.Add64(x, y, 0)
+ return sum, carryOut != 0
+}
+
+// SafeMul returns x*y and checks for overflow.
+func SafeMul(x, y uint64) (uint64, bool) {
+ hi, lo := bits.Mul64(x, y)
+ return lo, hi != 0
+}