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-rw-r--r--vendor/gopkg.in/src-d/go-git.v4/utils/binary/read.go180
1 files changed, 0 insertions, 180 deletions
diff --git a/vendor/gopkg.in/src-d/go-git.v4/utils/binary/read.go b/vendor/gopkg.in/src-d/go-git.v4/utils/binary/read.go
deleted file mode 100644
index 12e57c300e..0000000000
--- a/vendor/gopkg.in/src-d/go-git.v4/utils/binary/read.go
+++ /dev/null
@@ -1,180 +0,0 @@
-// Package binary implements sintax-sugar functions on top of the standard
-// library binary package
-package binary
-
-import (
- "bufio"
- "encoding/binary"
- "io"
-
- "gopkg.in/src-d/go-git.v4/plumbing"
-)
-
-// Read reads structured binary data from r into data. Bytes are read and
-// decoded in BigEndian order
-// https://golang.org/pkg/encoding/binary/#Read
-func Read(r io.Reader, data ...interface{}) error {
- for _, v := range data {
- if err := binary.Read(r, binary.BigEndian, v); err != nil {
- return err
- }
- }
-
- return nil
-}
-
-// ReadUntil reads from r untin delim is found
-func ReadUntil(r io.Reader, delim byte) ([]byte, error) {
- if bufr, ok := r.(*bufio.Reader); ok {
- return ReadUntilFromBufioReader(bufr, delim)
- }
-
- var buf [1]byte
- value := make([]byte, 0, 16)
- for {
- if _, err := io.ReadFull(r, buf[:]); err != nil {
- if err == io.EOF {
- return nil, err
- }
-
- return nil, err
- }
-
- if buf[0] == delim {
- return value, nil
- }
-
- value = append(value, buf[0])
- }
-}
-
-// ReadUntilFromBufioReader is like bufio.ReadBytes but drops the delimiter
-// from the result.
-func ReadUntilFromBufioReader(r *bufio.Reader, delim byte) ([]byte, error) {
- value, err := r.ReadBytes(delim)
- if err != nil || len(value) == 0 {
- return nil, err
- }
-
- return value[:len(value)-1], nil
-}
-
-// ReadVariableWidthInt reads and returns an int in Git VLQ special format:
-//
-// Ordinary VLQ has some redundancies, example: the number 358 can be
-// encoded as the 2-octet VLQ 0x8166 or the 3-octet VLQ 0x808166 or the
-// 4-octet VLQ 0x80808166 and so forth.
-//
-// To avoid these redundancies, the VLQ format used in Git removes this
-// prepending redundancy and extends the representable range of shorter
-// VLQs by adding an offset to VLQs of 2 or more octets in such a way
-// that the lowest possible value for such an (N+1)-octet VLQ becomes
-// exactly one more than the maximum possible value for an N-octet VLQ.
-// In particular, since a 1-octet VLQ can store a maximum value of 127,
-// the minimum 2-octet VLQ (0x8000) is assigned the value 128 instead of
-// 0. Conversely, the maximum value of such a 2-octet VLQ (0xff7f) is
-// 16511 instead of just 16383. Similarly, the minimum 3-octet VLQ
-// (0x808000) has a value of 16512 instead of zero, which means
-// that the maximum 3-octet VLQ (0xffff7f) is 2113663 instead of
-// just 2097151. And so forth.
-//
-// This is how the offset is saved in C:
-//
-// dheader[pos] = ofs & 127;
-// while (ofs >>= 7)
-// dheader[--pos] = 128 | (--ofs & 127);
-//
-func ReadVariableWidthInt(r io.Reader) (int64, error) {
- var c byte
- if err := Read(r, &c); err != nil {
- return 0, err
- }
-
- var v = int64(c & maskLength)
- for c&maskContinue > 0 {
- v++
- if err := Read(r, &c); err != nil {
- return 0, err
- }
-
- v = (v << lengthBits) + int64(c&maskLength)
- }
-
- return v, nil
-}
-
-const (
- maskContinue = uint8(128) // 1000 000
- maskLength = uint8(127) // 0111 1111
- lengthBits = uint8(7) // subsequent bytes has 7 bits to store the length
-)
-
-// ReadUint64 reads 8 bytes and returns them as a BigEndian uint32
-func ReadUint64(r io.Reader) (uint64, error) {
- var v uint64
- if err := binary.Read(r, binary.BigEndian, &v); err != nil {
- return 0, err
- }
-
- return v, nil
-}
-
-// ReadUint32 reads 4 bytes and returns them as a BigEndian uint32
-func ReadUint32(r io.Reader) (uint32, error) {
- var v uint32
- if err := binary.Read(r, binary.BigEndian, &v); err != nil {
- return 0, err
- }
-
- return v, nil
-}
-
-// ReadUint16 reads 2 bytes and returns them as a BigEndian uint16
-func ReadUint16(r io.Reader) (uint16, error) {
- var v uint16
- if err := binary.Read(r, binary.BigEndian, &v); err != nil {
- return 0, err
- }
-
- return v, nil
-}
-
-// ReadHash reads a plumbing.Hash from r
-func ReadHash(r io.Reader) (plumbing.Hash, error) {
- var h plumbing.Hash
- if err := binary.Read(r, binary.BigEndian, h[:]); err != nil {
- return plumbing.ZeroHash, err
- }
-
- return h, nil
-}
-
-const sniffLen = 8000
-
-// IsBinary detects if data is a binary value based on:
-// http://git.kernel.org/cgit/git/git.git/tree/xdiff-interface.c?id=HEAD#n198
-func IsBinary(r io.Reader) (bool, error) {
- reader := bufio.NewReader(r)
- c := 0
- for {
- if c == sniffLen {
- break
- }
-
- b, err := reader.ReadByte()
- if err == io.EOF {
- break
- }
- if err != nil {
- return false, err
- }
-
- if b == byte(0) {
- return true, nil
- }
-
- c++
- }
-
- return false, nil
-}