go/usr/gri/pretty/platform.go
Rob Pike aaf63f8d06 Step 1 of the Big Error Shift: make os.Error an interface and replace *os.Errors with os.Errors.
lib/template updated to use new setup; its clients also updated.

Step 2 will make os's error support internally much cleaner.

R=rsc
OCL=27586
CL=27586
2009-04-17 00:08:24 -07:00

84 lines
1.8 KiB
Go

// Copyright 2009 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 Platform
import IO "io"
import OS "os"
import Utils "utils"
// ----------------------------------------------------------------------------
// Environment
var
GOARCH,
GOOS,
GOROOT,
USER string;
func init() {
var e OS.Error;
GOARCH, e = OS.Getenv("GOARCH");
GOOS, e = OS.Getenv("GOOS");
GOROOT, e = OS.Getenv("GOROOT");
USER, e = OS.Getenv("USER");
}
// ----------------------------------------------------------------------------
// I/O
const (
MAGIC_obj_file = "@gri-go.7@v0"; // make it clear that it cannot be a source file
Src_file_ext = ".go";
Obj_file_ext = ".7";
)
func readfile(filename string) ([]byte, OS.Error) {
f, err := OS.Open(filename, OS.O_RDONLY, 0);
if err != nil {
return []byte{}, err;
}
var buf [1<<20]byte;
n, err1 := IO.Readn(f, &buf);
f.Close();
if err1 == IO.ErrEOF {
err1 = nil;
}
return buf[0:n], err1;
}
func writefile(name, data string) OS.Error {
fd, err := OS.Open(name, OS.O_WRONLY, 0);
if err != nil {
return err;
}
n, err1 := IO.WriteString(fd, data);
fd.Close();
return err1;
}
func ReadObjectFile(filename string) ([]byte, bool) {
data, err := readfile(filename + Obj_file_ext);
magic := MAGIC_obj_file; // TODO remove once len(constant) works
if err == nil && len(data) >= len(magic) && string(data[0 : len(magic)]) == magic {
return data, true;
}
return []byte{}, false;
}
func ReadSourceFile(name string) ([]byte, bool) {
name = Utils.TrimExt(name, Src_file_ext) + Src_file_ext;
data, err := readfile(name);
return data, err == nil;
}
func WriteObjectFile(name string, data string) bool {
name = Utils.TrimExt(Utils.BaseName(name), Src_file_ext) + Obj_file_ext;
return writefile(name, data) != nil;
}