Godeps, vendor: convert dependency management to trash (#3198)

This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.

1 files changed, 0 insertions, 356 deletions

diff --git a/Godeps/_workspace/src/github.com/golang/snappy/encode.go b/Godeps/_workspace/src/github.com/golang/snappy/encode.go
deleted file mode 100644
index 834e3b06a..000000000
--- a/Godeps/_workspace/src/github.com/golang/snappy/encode.go
+++ /dev/null
@@ -1,356 +0,0 @@
-// Copyright 2011 The Snappy-Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package snappy
-
-import (
-	"encoding/binary"
-	"errors"
-	"io"
-)
-
-// We limit how far copy back-references can go, the same as the C++ code.
-const maxOffset = 1 << 15
-
-// emitLiteral writes a literal chunk and returns the number of bytes written.
-func emitLiteral(dst, lit []byte) int {
-	i, n := 0, uint(len(lit)-1)
-	switch {
-	case n < 60:
-		dst[0] = uint8(n)<<2 | tagLiteral
-		i = 1
-	case n < 1<<8:
-		dst[0] = 60<<2 | tagLiteral
-		dst[1] = uint8(n)
-		i = 2
-	case n < 1<<16:
-		dst[0] = 61<<2 | tagLiteral
-		dst[1] = uint8(n)
-		dst[2] = uint8(n >> 8)
-		i = 3
-	case n < 1<<24:
-		dst[0] = 62<<2 | tagLiteral
-		dst[1] = uint8(n)
-		dst[2] = uint8(n >> 8)
-		dst[3] = uint8(n >> 16)
-		i = 4
-	case int64(n) < 1<<32:
-		dst[0] = 63<<2 | tagLiteral
-		dst[1] = uint8(n)
-		dst[2] = uint8(n >> 8)
-		dst[3] = uint8(n >> 16)
-		dst[4] = uint8(n >> 24)
-		i = 5
-	default:
-		panic("snappy: source buffer is too long")
-	}
-	if copy(dst[i:], lit) != len(lit) {
-		panic("snappy: destination buffer is too short")
-	}
-	return i + len(lit)
-}
-
-// emitCopy writes a copy chunk and returns the number of bytes written.
-func emitCopy(dst []byte, offset, length int) int {
-	i := 0
-	for length > 0 {
-		x := length - 4
-		if 0 <= x && x < 1<<3 && offset < 1<<11 {
-			dst[i+0] = uint8(offset>>8)&0x07<<5 | uint8(x)<<2 | tagCopy1
-			dst[i+1] = uint8(offset)
-			i += 2
-			break
-		}
-
-		x = length
-		if x > 1<<6 {
-			x = 1 << 6
-		}
-		dst[i+0] = uint8(x-1)<<2 | tagCopy2
-		dst[i+1] = uint8(offset)
-		dst[i+2] = uint8(offset >> 8)
-		i += 3
-		length -= x
-	}
-	return i
-}
-
-// Encode returns the encoded form of src. The returned slice may be a sub-
-// slice of dst if dst was large enough to hold the entire encoded block.
-// Otherwise, a newly allocated slice will be returned.
-// It is valid to pass a nil dst.
-func Encode(dst, src []byte) []byte {
-	if n := MaxEncodedLen(len(src)); len(dst) < n {
-		dst = make([]byte, n)
-	}
-
-	// The block starts with the varint-encoded length of the decompressed bytes.
-	d := binary.PutUvarint(dst, uint64(len(src)))
-
-	// Return early if src is short.
-	if len(src) <= 4 {
-		if len(src) != 0 {
-			d += emitLiteral(dst[d:], src)
-		}
-		return dst[:d]
-	}
-
-	// Initialize the hash table. Its size ranges from 1<<8 to 1<<14 inclusive.
-	const maxTableSize = 1 << 14
-	shift, tableSize := uint(32-8), 1<<8
-	for tableSize < maxTableSize && tableSize < len(src) {
-		shift--
-		tableSize *= 2
-	}
-	var table [maxTableSize]int
-
-	// Iterate over the source bytes.
-	var (
-		s   int // The iterator position.
-		t   int // The last position with the same hash as s.
-		lit int // The start position of any pending literal bytes.
-	)
-	for s+3 < len(src) {
-		// Update the hash table.
-		b0, b1, b2, b3 := src[s], src[s+1], src[s+2], src[s+3]
-		h := uint32(b0) | uint32(b1)<<8 | uint32(b2)<<16 | uint32(b3)<<24
-		p := &table[(h*0x1e35a7bd)>>shift]
-		// We need to to store values in [-1, inf) in table. To save
-		// some initialization time, (re)use the table's zero value
-		// and shift the values against this zero: add 1 on writes,
-		// subtract 1 on reads.
-		t, *p = *p-1, s+1
-		// If t is invalid or src[s:s+4] differs from src[t:t+4], accumulate a literal byte.
-		if t < 0 || s-t >= maxOffset || b0 != src[t] || b1 != src[t+1] || b2 != src[t+2] || b3 != src[t+3] {
-			// Skip multiple bytes if the last match was >= 32 bytes prior.
-			s += 1 + (s-lit)>>5
-			continue
-		}
-		// Otherwise, we have a match. First, emit any pending literal bytes.
-		if lit != s {
-			d += emitLiteral(dst[d:], src[lit:s])
-		}
-		// Extend the match to be as long as possible.
-		s0 := s
-		s, t = s+4, t+4
-		for s < len(src) && src[s] == src[t] {
-			s++
-			t++
-		}
-		// Emit the copied bytes.
-		d += emitCopy(dst[d:], s-t, s-s0)
-		lit = s
-	}
-
-	// Emit any final pending literal bytes and return.
-	if lit != len(src) {
-		d += emitLiteral(dst[d:], src[lit:])
-	}
-	return dst[:d]
-}
-
-// MaxEncodedLen returns the maximum length of a snappy block, given its
-// uncompressed length.
-func MaxEncodedLen(srcLen int) int {
-	// Compressed data can be defined as:
-	//    compressed := item* literal*
-	//    item       := literal* copy
-	//
-	// The trailing literal sequence has a space blowup of at most 62/60
-	// since a literal of length 60 needs one tag byte + one extra byte
-	// for length information.
-	//
-	// Item blowup is trickier to measure. Suppose the "copy" op copies
-	// 4 bytes of data. Because of a special check in the encoding code,
-	// we produce a 4-byte copy only if the offset is < 65536. Therefore
-	// the copy op takes 3 bytes to encode, and this type of item leads
-	// to at most the 62/60 blowup for representing literals.
-	//
-	// Suppose the "copy" op copies 5 bytes of data. If the offset is big
-	// enough, it will take 5 bytes to encode the copy op. Therefore the
-	// worst case here is a one-byte literal followed by a five-byte copy.
-	// That is, 6 bytes of input turn into 7 bytes of "compressed" data.
-	//
-	// This last factor dominates the blowup, so the final estimate is:
-	return 32 + srcLen + srcLen/6
-}
-
-var errClosed = errors.New("snappy: Writer is closed")
-
-// NewWriter returns a new Writer that compresses to w.
-//
-// The Writer returned does not buffer writes. There is no need to Flush or
-// Close such a Writer.
-//
-// Deprecated: the Writer returned is not suitable for many small writes, only
-// for few large writes. Use NewBufferedWriter instead, which is efficient
-// regardless of the frequency and shape of the writes, and remember to Close
-// that Writer when done.
-func NewWriter(w io.Writer) *Writer {
-	return &Writer{
-		w:    w,
-		obuf: make([]byte, obufLen),
-	}
-}
-
-// NewBufferedWriter returns a new Writer that compresses to w, using the
-// framing format described at
-// https://github.com/google/snappy/blob/master/framing_format.txt
-//
-// The Writer returned buffers writes. Users must call Close to guarantee all
-// data has been forwarded to the underlying io.Writer. They may also call
-// Flush zero or more times before calling Close.
-func NewBufferedWriter(w io.Writer) *Writer {
-	return &Writer{
-		w:    w,
-		ibuf: make([]byte, 0, maxUncompressedChunkLen),
-		obuf: make([]byte, obufLen),
-	}
-}
-
-// Writer is an io.Writer than can write Snappy-compressed bytes.
-type Writer struct {
-	w   io.Writer
-	err error
-
-	// ibuf is a buffer for the incoming (uncompressed) bytes.
-	//
-	// Its use is optional. For backwards compatibility, Writers created by the
-	// NewWriter function have ibuf == nil, do not buffer incoming bytes, and
-	// therefore do not need to be Flush'ed or Close'd.
-	ibuf []byte
-
-	// obuf is a buffer for the outgoing (compressed) bytes.
-	obuf []byte
-
-	// wroteStreamHeader is whether we have written the stream header.
-	wroteStreamHeader bool
-}
-
-// Reset discards the writer's state and switches the Snappy writer to write to
-// w. This permits reusing a Writer rather than allocating a new one.
-func (w *Writer) Reset(writer io.Writer) {
-	w.w = writer
-	w.err = nil
-	if w.ibuf != nil {
-		w.ibuf = w.ibuf[:0]
-	}
-	w.wroteStreamHeader = false
-}
-
-// Write satisfies the io.Writer interface.
-func (w *Writer) Write(p []byte) (nRet int, errRet error) {
-	if w.ibuf == nil {
-		// Do not buffer incoming bytes. This does not perform or compress well
-		// if the caller of Writer.Write writes many small slices. This
-		// behavior is therefore deprecated, but still supported for backwards
-		// compatibility with code that doesn't explicitly Flush or Close.
-		return w.write(p)
-	}
-
-	// The remainder of this method is based on bufio.Writer.Write from the
-	// standard library.
-
-	for len(p) > (cap(w.ibuf)-len(w.ibuf)) && w.err == nil {
-		var n int
-		if len(w.ibuf) == 0 {
-			// Large write, empty buffer.
-			// Write directly from p to avoid copy.
-			n, _ = w.write(p)
-		} else {
-			n = copy(w.ibuf[len(w.ibuf):cap(w.ibuf)], p)
-			w.ibuf = w.ibuf[:len(w.ibuf)+n]
-			w.Flush()
-		}
-		nRet += n
-		p = p[n:]
-	}
-	if w.err != nil {
-		return nRet, w.err
-	}
-	n := copy(w.ibuf[len(w.ibuf):cap(w.ibuf)], p)
-	w.ibuf = w.ibuf[:len(w.ibuf)+n]
-	nRet += n
-	return nRet, nil
-}
-
-func (w *Writer) write(p []byte) (nRet int, errRet error) {
-	if w.err != nil {
-		return 0, w.err
-	}
-	for len(p) > 0 {
-		obufStart := len(magicChunk)
-		if !w.wroteStreamHeader {
-			w.wroteStreamHeader = true
-			copy(w.obuf, magicChunk)
-			obufStart = 0
-		}
-
-		var uncompressed []byte
-		if len(p) > maxUncompressedChunkLen {
-			uncompressed, p = p[:maxUncompressedChunkLen], p[maxUncompressedChunkLen:]
-		} else {
-			uncompressed, p = p, nil
-		}
-		checksum := crc(uncompressed)
-
-		// Compress the buffer, discarding the result if the improvement
-		// isn't at least 12.5%.
-		compressed := Encode(w.obuf[obufHeaderLen:], uncompressed)
-		chunkType := uint8(chunkTypeCompressedData)
-		chunkLen := 4 + len(compressed)
-		obufEnd := obufHeaderLen + len(compressed)
-		if len(compressed) >= len(uncompressed)-len(uncompressed)/8 {
-			chunkType = chunkTypeUncompressedData
-			chunkLen = 4 + len(uncompressed)
-			obufEnd = obufHeaderLen
-		}
-
-		// Fill in the per-chunk header that comes before the body.
-		w.obuf[len(magicChunk)+0] = chunkType
-		w.obuf[len(magicChunk)+1] = uint8(chunkLen >> 0)
-		w.obuf[len(magicChunk)+2] = uint8(chunkLen >> 8)
-		w.obuf[len(magicChunk)+3] = uint8(chunkLen >> 16)
-		w.obuf[len(magicChunk)+4] = uint8(checksum >> 0)
-		w.obuf[len(magicChunk)+5] = uint8(checksum >> 8)
-		w.obuf[len(magicChunk)+6] = uint8(checksum >> 16)
-		w.obuf[len(magicChunk)+7] = uint8(checksum >> 24)
-
-		if _, err := w.w.Write(w.obuf[obufStart:obufEnd]); err != nil {
-			w.err = err
-			return nRet, err
-		}
-		if chunkType == chunkTypeUncompressedData {
-			if _, err := w.w.Write(uncompressed); err != nil {
-				w.err = err
-				return nRet, err
-			}
-		}
-		nRet += len(uncompressed)
-	}
-	return nRet, nil
-}
-
-// Flush flushes the Writer to its underlying io.Writer.
-func (w *Writer) Flush() error {
-	if w.err != nil {
-		return w.err
-	}
-	if len(w.ibuf) == 0 {
-		return nil
-	}
-	w.write(w.ibuf)
-	w.ibuf = w.ibuf[:0]
-	return w.err
-}
-
-// Close calls Flush and then closes the Writer.
-func (w *Writer) Close() error {
-	w.Flush()
-	ret := w.err
-	if w.err == nil {
-		w.err = errClosed
-	}
-	return ret
-}