gcc/libgo/go/os/env_unix.go
Ian Lance Taylor 7a9389330e Add Go frontend, libgo library, and Go testsuite.
gcc/:
	* gcc.c (default_compilers): Add entry for ".go".
	* common.opt: Add -static-libgo as a driver option.
	* doc/install.texi (Configuration): Mention libgo as an option for
	--enable-shared.  Mention go as an option for --enable-languages.
	* doc/invoke.texi (Overall Options): Mention .go as a file name
	suffix.  Mention go as a -x option.
	* doc/frontends.texi (G++ and GCC): Mention Go as a supported
	language.
	* doc/sourcebuild.texi (Top Level): Mention libgo.
	* doc/standards.texi (Standards): Add section on Go language.
	Move references for other languages into their own section.
	* doc/contrib.texi (Contributors): Mention that I contributed the
	Go frontend.
gcc/testsuite/:
	* lib/go.exp: New file.
	* lib/go-dg.exp: New file.
	* lib/go-torture.exp: New file.
	* lib/target-supports.exp (check_compile): Match // Go.

From-SVN: r167407
2010-12-03 04:34:57 +00:00

97 lines
2.0 KiB
Go

// 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.
// Unix environment variables.
package os
import (
"sync"
)
// ENOENV is the Error indicating that an environment variable does not exist.
var ENOENV = NewError("no such environment variable")
var env map[string]string
var once sync.Once
func copyenv() {
env = make(map[string]string)
for _, s := range Envs {
for j := 0; j < len(s); j++ {
if s[j] == '=' {
env[s[0:j]] = s[j+1:]
break
}
}
}
}
// Getenverror retrieves the value of the environment variable named by the key.
// It returns the value and an error, if any.
func Getenverror(key string) (value string, err Error) {
once.Do(copyenv)
if len(key) == 0 {
return "", EINVAL
}
v, ok := env[key]
if !ok {
return "", ENOENV
}
return v, nil
}
// Getenv retrieves the value of the environment variable named by the key.
// It returns the value, which will be empty if the variable is not present.
func Getenv(key string) string {
v, _ := Getenverror(key)
return v
}
// Setenv sets the value of the environment variable named by the key.
// It returns an Error, if any.
func Setenv(key, value string) Error {
once.Do(copyenv)
if len(key) == 0 {
return EINVAL
}
env[key] = value
return nil
}
// Clearenv deletes all environment variables.
func Clearenv() {
once.Do(copyenv) // prevent copyenv in Getenv/Setenv
env = make(map[string]string)
}
// Environ returns an array of strings representing the environment,
// in the form "key=value".
func Environ() []string {
once.Do(copyenv)
a := make([]string, len(env))
i := 0
for k, v := range env {
// check i < len(a) for safety,
// in case env is changing underfoot.
if i < len(a) {
a[i] = k + "=" + v
i++
}
}
return a[0:i]
}
// TempDir returns the default directory to use for temporary files.
func TempDir() string {
dir := Getenv("TMPDIR")
if dir == "" {
dir = "/tmp"
}
return dir
}