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Diffstat (limited to 'vendor/github.com/boombuler/barcode/utils/bitlist.go')
-rw-r--r--vendor/github.com/boombuler/barcode/utils/bitlist.go119
1 files changed, 119 insertions, 0 deletions
diff --git a/vendor/github.com/boombuler/barcode/utils/bitlist.go b/vendor/github.com/boombuler/barcode/utils/bitlist.go
new file mode 100644
index 00000000..bb05e53b
--- /dev/null
+++ b/vendor/github.com/boombuler/barcode/utils/bitlist.go
@@ -0,0 +1,119 @@
+package utils
+
+// BitList is a list that contains bits
+type BitList struct {
+ count int
+ data []int32
+}
+
+// NewBitList returns a new BitList with the given length
+// all bits are initialize with false
+func NewBitList(capacity int) *BitList {
+ bl := new(BitList)
+ bl.count = capacity
+ x := 0
+ if capacity%32 != 0 {
+ x = 1
+ }
+ bl.data = make([]int32, capacity/32+x)
+ return bl
+}
+
+// Len returns the number of contained bits
+func (bl *BitList) Len() int {
+ return bl.count
+}
+
+func (bl *BitList) grow() {
+ growBy := len(bl.data)
+ if growBy < 128 {
+ growBy = 128
+ } else if growBy >= 1024 {
+ growBy = 1024
+ }
+
+ nd := make([]int32, len(bl.data)+growBy)
+ copy(nd, bl.data)
+ bl.data = nd
+}
+
+// AddBit appends the given bits to the end of the list
+func (bl *BitList) AddBit(bits ...bool) {
+ for _, bit := range bits {
+ itmIndex := bl.count / 32
+ for itmIndex >= len(bl.data) {
+ bl.grow()
+ }
+ bl.SetBit(bl.count, bit)
+ bl.count++
+ }
+}
+
+// SetBit sets the bit at the given index to the given value
+func (bl *BitList) SetBit(index int, value bool) {
+ itmIndex := index / 32
+ itmBitShift := 31 - (index % 32)
+ if value {
+ bl.data[itmIndex] = bl.data[itmIndex] | 1<<uint(itmBitShift)
+ } else {
+ bl.data[itmIndex] = bl.data[itmIndex] & ^(1 << uint(itmBitShift))
+ }
+}
+
+// GetBit returns the bit at the given index
+func (bl *BitList) GetBit(index int) bool {
+ itmIndex := index / 32
+ itmBitShift := 31 - (index % 32)
+ return ((bl.data[itmIndex] >> uint(itmBitShift)) & 1) == 1
+}
+
+// AddByte appends all 8 bits of the given byte to the end of the list
+func (bl *BitList) AddByte(b byte) {
+ for i := 7; i >= 0; i-- {
+ bl.AddBit(((b >> uint(i)) & 1) == 1)
+ }
+}
+
+// AddBits appends the last (LSB) 'count' bits of 'b' the the end of the list
+func (bl *BitList) AddBits(b int, count byte) {
+ for i := int(count) - 1; i >= 0; i-- {
+ bl.AddBit(((b >> uint(i)) & 1) == 1)
+ }
+}
+
+// GetBytes returns all bits of the BitList as a []byte
+func (bl *BitList) GetBytes() []byte {
+ len := bl.count >> 3
+ if (bl.count % 8) != 0 {
+ len++
+ }
+ result := make([]byte, len)
+ for i := 0; i < len; i++ {
+ shift := (3 - (i % 4)) * 8
+ result[i] = (byte)((bl.data[i/4] >> uint(shift)) & 0xFF)
+ }
+ return result
+}
+
+// IterateBytes iterates through all bytes contained in the BitList
+func (bl *BitList) IterateBytes() <-chan byte {
+ res := make(chan byte)
+
+ go func() {
+ c := bl.count
+ shift := 24
+ i := 0
+ for c > 0 {
+ res <- byte((bl.data[i] >> uint(shift)) & 0xFF)
+ shift -= 8
+ if shift < 0 {
+ shift = 24
+ i++
+ }
+ c -= 8
+ }
+ close(res)
+ }()
+
+ return res
+}