Imported Upstream version 1.4upstream/1.4

1 files changed, 63 insertions, 0 deletions

diff --git a/src/runtime/env_posix.go b/src/runtime/env_posix.go
new file mode 100644
index 000000000..dd57872d7
--- /dev/null
+++ b/src/runtime/env_posix.go
@@ -0,0 +1,63 @@
+// Copyright 2012 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.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
+
+package runtime
+
+import "unsafe"
+
+func environ() []string
+
+func getenv(s *byte) *byte {
+	val := gogetenv(gostringnocopy(s))
+	if val == "" {
+		return nil
+	}
+	// Strings found in environment are NUL-terminated.
+	return &bytes(val)[0]
+}
+
+func gogetenv(key string) string {
+	env := environ()
+	if env == nil {
+		gothrow("getenv before env init")
+	}
+	for _, s := range environ() {
+		if len(s) > len(key) && s[len(key)] == '=' && s[:len(key)] == key {
+			return s[len(key)+1:]
+		}
+	}
+	return ""
+}
+
+var _cgo_setenv uintptr   // pointer to C function
+var _cgo_unsetenv uintptr // pointer to C function
+
+// Update the C environment if cgo is loaded.
+// Called from syscall.Setenv.
+func syscall_setenv_c(k string, v string) {
+	if _cgo_setenv == 0 {
+		return
+	}
+	arg := [2]unsafe.Pointer{cstring(k), cstring(v)}
+	asmcgocall(unsafe.Pointer(_cgo_setenv), unsafe.Pointer(&arg))
+}
+
+// Update the C environment if cgo is loaded.
+// Called from syscall.unsetenv.
+func syscall_unsetenv_c(k string) {
+	if _cgo_unsetenv == 0 {
+		return
+	}
+	arg := [1]unsafe.Pointer{cstring(k)}
+	asmcgocall(unsafe.Pointer(_cgo_unsetenv), unsafe.Pointer(&arg))
+}
+
+func cstring(s string) unsafe.Pointer {
+	p := make([]byte, len(s)+1)
+	sp := (*_string)(unsafe.Pointer(&s))
+	memmove(unsafe.Pointer(&p[0]), unsafe.Pointer(sp.str), uintptr(len(s)))
+	return unsafe.Pointer(&p[0])
+}