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Diffstat (limited to 'vendor/gopkg.in/gcfg.v1/token/position.go')
| -rw-r--r-- | vendor/gopkg.in/gcfg.v1/token/position.go | 435 |
1 files changed, 0 insertions, 435 deletions
diff --git a/vendor/gopkg.in/gcfg.v1/token/position.go b/vendor/gopkg.in/gcfg.v1/token/position.go deleted file mode 100644 index fc45c1e7..00000000 --- a/vendor/gopkg.in/gcfg.v1/token/position.go +++ /dev/null @@ -1,435 +0,0 @@ -// Copyright 2010 The 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. - -// TODO(gri) consider making this a separate package outside the go directory. - -package token - -import ( - "fmt" - "sort" - "sync" -) - -// ----------------------------------------------------------------------------- -// Positions - -// Position describes an arbitrary source position -// including the file, line, and column location. -// A Position is valid if the line number is > 0. -// -type Position struct { - Filename string // filename, if any - Offset int // offset, starting at 0 - Line int // line number, starting at 1 - Column int // column number, starting at 1 (character count) -} - -// IsValid returns true if the position is valid. -func (pos *Position) IsValid() bool { return pos.Line > 0 } - -// String returns a string in one of several forms: -// -// file:line:column valid position with file name -// line:column valid position without file name -// file invalid position with file name -// - invalid position without file name -// -func (pos Position) String() string { - s := pos.Filename - if pos.IsValid() { - if s != "" { - s += ":" - } - s += fmt.Sprintf("%d:%d", pos.Line, pos.Column) - } - if s == "" { - s = "-" - } - return s -} - -// Pos is a compact encoding of a source position within a file set. -// It can be converted into a Position for a more convenient, but much -// larger, representation. -// -// The Pos value for a given file is a number in the range [base, base+size], -// where base and size are specified when adding the file to the file set via -// AddFile. -// -// To create the Pos value for a specific source offset, first add -// the respective file to the current file set (via FileSet.AddFile) -// and then call File.Pos(offset) for that file. Given a Pos value p -// for a specific file set fset, the corresponding Position value is -// obtained by calling fset.Position(p). -// -// Pos values can be compared directly with the usual comparison operators: -// If two Pos values p and q are in the same file, comparing p and q is -// equivalent to comparing the respective source file offsets. If p and q -// are in different files, p < q is true if the file implied by p was added -// to the respective file set before the file implied by q. -// -type Pos int - -// The zero value for Pos is NoPos; there is no file and line information -// associated with it, and NoPos().IsValid() is false. NoPos is always -// smaller than any other Pos value. The corresponding Position value -// for NoPos is the zero value for Position. -// -const NoPos Pos = 0 - -// IsValid returns true if the position is valid. -func (p Pos) IsValid() bool { - return p != NoPos -} - -// ----------------------------------------------------------------------------- -// File - -// A File is a handle for a file belonging to a FileSet. -// A File has a name, size, and line offset table. -// -type File struct { - set *FileSet - name string // file name as provided to AddFile - base int // Pos value range for this file is [base...base+size] - size int // file size as provided to AddFile - - // lines and infos are protected by set.mutex - lines []int - infos []lineInfo -} - -// Name returns the file name of file f as registered with AddFile. -func (f *File) Name() string { - return f.name -} - -// Base returns the base offset of file f as registered with AddFile. -func (f *File) Base() int { - return f.base -} - -// Size returns the size of file f as registered with AddFile. -func (f *File) Size() int { - return f.size -} - -// LineCount returns the number of lines in file f. -func (f *File) LineCount() int { - f.set.mutex.RLock() - n := len(f.lines) - f.set.mutex.RUnlock() - return n -} - -// AddLine adds the line offset for a new line. -// The line offset must be larger than the offset for the previous line -// and smaller than the file size; otherwise the line offset is ignored. -// -func (f *File) AddLine(offset int) { - f.set.mutex.Lock() - if i := len(f.lines); (i == 0 || f.lines[i-1] < offset) && offset < f.size { - f.lines = append(f.lines, offset) - } - f.set.mutex.Unlock() -} - -// SetLines sets the line offsets for a file and returns true if successful. -// The line offsets are the offsets of the first character of each line; -// for instance for the content "ab\nc\n" the line offsets are {0, 3}. -// An empty file has an empty line offset table. -// Each line offset must be larger than the offset for the previous line -// and smaller than the file size; otherwise SetLines fails and returns -// false. -// -func (f *File) SetLines(lines []int) bool { - // verify validity of lines table - size := f.size - for i, offset := range lines { - if i > 0 && offset <= lines[i-1] || size <= offset { - return false - } - } - - // set lines table - f.set.mutex.Lock() - f.lines = lines - f.set.mutex.Unlock() - return true -} - -// SetLinesForContent sets the line offsets for the given file content. -func (f *File) SetLinesForContent(content []byte) { - var lines []int - line := 0 - for offset, b := range content { - if line >= 0 { - lines = append(lines, line) - } - line = -1 - if b == '\n' { - line = offset + 1 - } - } - - // set lines table - f.set.mutex.Lock() - f.lines = lines - f.set.mutex.Unlock() -} - -// A lineInfo object describes alternative file and line number -// information (such as provided via a //line comment in a .go -// file) for a given file offset. -type lineInfo struct { - // fields are exported to make them accessible to gob - Offset int - Filename string - Line int -} - -// AddLineInfo adds alternative file and line number information for -// a given file offset. The offset must be larger than the offset for -// the previously added alternative line info and smaller than the -// file size; otherwise the information is ignored. -// -// AddLineInfo is typically used to register alternative position -// information for //line filename:line comments in source files. -// -func (f *File) AddLineInfo(offset int, filename string, line int) { - f.set.mutex.Lock() - if i := len(f.infos); i == 0 || f.infos[i-1].Offset < offset && offset < f.size { - f.infos = append(f.infos, lineInfo{offset, filename, line}) - } - f.set.mutex.Unlock() -} - -// Pos returns the Pos value for the given file offset; -// the offset must be <= f.Size(). -// f.Pos(f.Offset(p)) == p. -// -func (f *File) Pos(offset int) Pos { - if offset > f.size { - panic("illegal file offset") - } - return Pos(f.base + offset) -} - -// Offset returns the offset for the given file position p; -// p must be a valid Pos value in that file. -// f.Offset(f.Pos(offset)) == offset. -// -func (f *File) Offset(p Pos) int { - if int(p) < f.base || int(p) > f.base+f.size { - panic("illegal Pos value") - } - return int(p) - f.base -} - -// Line returns the line number for the given file position p; -// p must be a Pos value in that file or NoPos. -// -func (f *File) Line(p Pos) int { - // TODO(gri) this can be implemented much more efficiently - return f.Position(p).Line -} - -func searchLineInfos(a []lineInfo, x int) int { - return sort.Search(len(a), func(i int) bool { return a[i].Offset > x }) - 1 -} - -// info returns the file name, line, and column number for a file offset. -func (f *File) info(offset int) (filename string, line, column int) { - filename = f.name - if i := searchInts(f.lines, offset); i >= 0 { - line, column = i+1, offset-f.lines[i]+1 - } - if len(f.infos) > 0 { - // almost no files have extra line infos - if i := searchLineInfos(f.infos, offset); i >= 0 { - alt := &f.infos[i] - filename = alt.Filename - if i := searchInts(f.lines, alt.Offset); i >= 0 { - line += alt.Line - i - 1 - } - } - } - return -} - -func (f *File) position(p Pos) (pos Position) { - offset := int(p) - f.base - pos.Offset = offset - pos.Filename, pos.Line, pos.Column = f.info(offset) - return -} - -// Position returns the Position value for the given file position p; -// p must be a Pos value in that file or NoPos. -// -func (f *File) Position(p Pos) (pos Position) { - if p != NoPos { - if int(p) < f.base || int(p) > f.base+f.size { - panic("illegal Pos value") - } - pos = f.position(p) - } - return -} - -// ----------------------------------------------------------------------------- -// FileSet - -// A FileSet represents a set of source files. -// Methods of file sets are synchronized; multiple goroutines -// may invoke them concurrently. -// -type FileSet struct { - mutex sync.RWMutex // protects the file set - base int // base offset for the next file - files []*File // list of files in the order added to the set - last *File // cache of last file looked up -} - -// NewFileSet creates a new file set. -func NewFileSet() *FileSet { - s := new(FileSet) - s.base = 1 // 0 == NoPos - return s -} - -// Base returns the minimum base offset that must be provided to -// AddFile when adding the next file. -// -func (s *FileSet) Base() int { - s.mutex.RLock() - b := s.base - s.mutex.RUnlock() - return b - -} - -// AddFile adds a new file with a given filename, base offset, and file size -// to the file set s and returns the file. Multiple files may have the same -// name. The base offset must not be smaller than the FileSet's Base(), and -// size must not be negative. -// -// Adding the file will set the file set's Base() value to base + size + 1 -// as the minimum base value for the next file. The following relationship -// exists between a Pos value p for a given file offset offs: -// -// int(p) = base + offs -// -// with offs in the range [0, size] and thus p in the range [base, base+size]. -// For convenience, File.Pos may be used to create file-specific position -// values from a file offset. -// -func (s *FileSet) AddFile(filename string, base, size int) *File { - s.mutex.Lock() - defer s.mutex.Unlock() - if base < s.base || size < 0 { - panic("illegal base or size") - } - // base >= s.base && size >= 0 - f := &File{s, filename, base, size, []int{0}, nil} - base += size + 1 // +1 because EOF also has a position - if base < 0 { - panic("token.Pos offset overflow (> 2G of source code in file set)") - } - // add the file to the file set - s.base = base - s.files = append(s.files, f) - s.last = f - return f -} - -// Iterate calls f for the files in the file set in the order they were added -// until f returns false. -// -func (s *FileSet) Iterate(f func(*File) bool) { - for i := 0; ; i++ { - var file *File - s.mutex.RLock() - if i < len(s.files) { - file = s.files[i] - } - s.mutex.RUnlock() - if file == nil || !f(file) { - break - } - } -} - -func searchFiles(a []*File, x int) int { - return sort.Search(len(a), func(i int) bool { return a[i].base > x }) - 1 -} - -func (s *FileSet) file(p Pos) *File { - // common case: p is in last file - if f := s.last; f != nil && f.base <= int(p) && int(p) <= f.base+f.size { - return f - } - // p is not in last file - search all files - if i := searchFiles(s.files, int(p)); i >= 0 { - f := s.files[i] - // f.base <= int(p) by definition of searchFiles - if int(p) <= f.base+f.size { - s.last = f - return f - } - } - return nil -} - -// File returns the file that contains the position p. -// If no such file is found (for instance for p == NoPos), -// the result is nil. -// -func (s *FileSet) File(p Pos) (f *File) { - if p != NoPos { - s.mutex.RLock() - f = s.file(p) - s.mutex.RUnlock() - } - return -} - -// Position converts a Pos in the fileset into a general Position. -func (s *FileSet) Position(p Pos) (pos Position) { - if p != NoPos { - s.mutex.RLock() - if f := s.file(p); f != nil { - pos = f.position(p) - } - s.mutex.RUnlock() - } - return -} - -// ----------------------------------------------------------------------------- -// Helper functions - -func searchInts(a []int, x int) int { - // This function body is a manually inlined version of: - // - // return sort.Search(len(a), func(i int) bool { return a[i] > x }) - 1 - // - // With better compiler optimizations, this may not be needed in the - // future, but at the moment this change improves the go/printer - // benchmark performance by ~30%. This has a direct impact on the - // speed of gofmt and thus seems worthwhile (2011-04-29). - // TODO(gri): Remove this when compilers have caught up. - i, j := 0, len(a) - for i < j { - h := i + (j-i)/2 // avoid overflow when computing h - // i ≤ h < j - if a[h] <= x { - i = h + 1 - } else { - j = h - } - } - return i - 1 -} |