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-rw-r--r--gcc-4.7/libgo/go/io/ioutil/tempfile.go91
1 files changed, 91 insertions, 0 deletions
diff --git a/gcc-4.7/libgo/go/io/ioutil/tempfile.go b/gcc-4.7/libgo/go/io/ioutil/tempfile.go
new file mode 100644
index 000000000..42d2e6758
--- /dev/null
+++ b/gcc-4.7/libgo/go/io/ioutil/tempfile.go
@@ -0,0 +1,91 @@
+// 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.
+
+package ioutil
+
+import (
+ "os"
+ "path/filepath"
+ "strconv"
+ "time"
+)
+
+// Random number state, accessed without lock; racy but harmless.
+// We generate random temporary file names so that there's a good
+// chance the file doesn't exist yet - keeps the number of tries in
+// TempFile to a minimum.
+var rand uint32
+
+func reseed() uint32 {
+ return uint32(time.Now().UnixNano() + int64(os.Getpid()))
+}
+
+func nextSuffix() string {
+ r := rand
+ if r == 0 {
+ r = reseed()
+ }
+ r = r*1664525 + 1013904223 // constants from Numerical Recipes
+ rand = r
+ return strconv.Itoa(int(1e9 + r%1e9))[1:]
+}
+
+// TempFile creates a new temporary file in the directory dir
+// with a name beginning with prefix, opens the file for reading
+// and writing, and returns the resulting *os.File.
+// If dir is the empty string, TempFile uses the default directory
+// for temporary files (see os.TempDir).
+// Multiple programs calling TempFile simultaneously
+// will not choose the same file. The caller can use f.Name()
+// to find the name of the file. It is the caller's responsibility to
+// remove the file when no longer needed.
+func TempFile(dir, prefix string) (f *os.File, err error) {
+ if dir == "" {
+ dir = os.TempDir()
+ }
+
+ nconflict := 0
+ for i := 0; i < 10000; i++ {
+ name := filepath.Join(dir, prefix+nextSuffix())
+ f, err = os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
+ if os.IsExist(err) {
+ if nconflict++; nconflict > 10 {
+ rand = reseed()
+ }
+ continue
+ }
+ break
+ }
+ return
+}
+
+// TempDir creates a new temporary directory in the directory dir
+// with a name beginning with prefix and returns the path of the
+// new directory. If dir is the empty string, TempDir uses the
+// default directory for temporary files (see os.TempDir).
+// Multiple programs calling TempDir simultaneously
+// will not choose the same directory. It is the caller's responsibility
+// to remove the directory when no longer needed.
+func TempDir(dir, prefix string) (name string, err error) {
+ if dir == "" {
+ dir = os.TempDir()
+ }
+
+ nconflict := 0
+ for i := 0; i < 10000; i++ {
+ try := filepath.Join(dir, prefix+nextSuffix())
+ err = os.Mkdir(try, 0700)
+ if os.IsExist(err) {
+ if nconflict++; nconflict > 10 {
+ rand = reseed()
+ }
+ continue
+ }
+ if err == nil {
+ name = try
+ }
+ break
+ }
+ return
+}