github.com/mdempsky/go@v0.0.0-20151201204031-5dd372bd1e70/src/cmd/dist/buildtool.go (about)

     1  // Copyright 2015 The Go Authors.  All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Build toolchain using Go 1.4.
     6  //
     7  // The general strategy is to copy the source files we need into
     8  // a new GOPATH workspace, adjust import paths appropriately,
     9  // invoke the Go 1.4 go command to build those sources,
    10  // and then copy the binaries back.
    11  
    12  package main
    13  
    14  import (
    15  	"os"
    16  	"strings"
    17  )
    18  
    19  // bootstrapDirs is a list of directories holding code that must be
    20  // compiled with a Go 1.4 toolchain to produce the bootstrapTargets.
    21  // All directories in this list are relative to and must be below $GOROOT/src/cmd.
    22  // The list is assumed to have two kinds of entries: names without slashes,
    23  // which are commands, and entries beginning with internal/, which are
    24  // packages supporting the commands.
    25  var bootstrapDirs = []string{
    26  	"asm",
    27  	"asm/internal/arch",
    28  	"asm/internal/asm",
    29  	"asm/internal/flags",
    30  	"asm/internal/lex",
    31  	"compile",
    32  	"compile/internal/amd64",
    33  	"compile/internal/arm",
    34  	"compile/internal/arm64",
    35  	"compile/internal/big",
    36  	"compile/internal/gc",
    37  	"compile/internal/mips64",
    38  	"compile/internal/ppc64",
    39  	"compile/internal/x86",
    40  	"internal/gcprog",
    41  	"internal/obj",
    42  	"internal/obj/arm",
    43  	"internal/obj/arm64",
    44  	"internal/obj/mips",
    45  	"internal/obj/ppc64",
    46  	"internal/obj/x86",
    47  	"link",
    48  	"link/internal/amd64",
    49  	"link/internal/arm",
    50  	"link/internal/arm64",
    51  	"link/internal/ld",
    52  	"link/internal/mips64",
    53  	"link/internal/ppc64",
    54  	"link/internal/x86",
    55  }
    56  
    57  func bootstrapBuildTools() {
    58  	goroot_bootstrap := os.Getenv("GOROOT_BOOTSTRAP")
    59  	if goroot_bootstrap == "" {
    60  		goroot_bootstrap = pathf("%s/go1.4", os.Getenv("HOME"))
    61  	}
    62  	xprintf("##### Building Go toolchain using %s.\n", goroot_bootstrap)
    63  
    64  	mkzbootstrap(pathf("%s/src/cmd/internal/obj/zbootstrap.go", goroot))
    65  
    66  	// Use $GOROOT/pkg/bootstrap as the bootstrap workspace root.
    67  	// We use a subdirectory of $GOROOT/pkg because that's the
    68  	// space within $GOROOT where we store all generated objects.
    69  	// We could use a temporary directory outside $GOROOT instead,
    70  	// but it is easier to debug on failure if the files are in a known location.
    71  	workspace := pathf("%s/pkg/bootstrap", goroot)
    72  	xremoveall(workspace)
    73  	base := pathf("%s/src/bootstrap", workspace)
    74  	xmkdirall(base)
    75  
    76  	// Copy source code into $GOROOT/pkg/bootstrap and rewrite import paths.
    77  	for _, dir := range bootstrapDirs {
    78  		src := pathf("%s/src/cmd/%s", goroot, dir)
    79  		dst := pathf("%s/%s", base, dir)
    80  		xmkdirall(dst)
    81  		for _, name := range xreaddirfiles(src) {
    82  			srcFile := pathf("%s/%s", src, name)
    83  			text := readfile(srcFile)
    84  			text = bootstrapFixImports(text, srcFile)
    85  			writefile(text, pathf("%s/%s", dst, name), 0)
    86  		}
    87  	}
    88  
    89  	// Set up environment for invoking Go 1.4 go command.
    90  	// GOROOT points at Go 1.4 GOROOT,
    91  	// GOPATH points at our bootstrap workspace,
    92  	// GOBIN is empty, so that binaries are installed to GOPATH/bin,
    93  	// and GOOS, GOHOSTOS, GOARCH, and GOHOSTOS are empty,
    94  	// so that Go 1.4 builds whatever kind of binary it knows how to build.
    95  	// Restore GOROOT, GOPATH, and GOBIN when done.
    96  	// Don't bother with GOOS, GOHOSTOS, GOARCH, and GOHOSTARCH,
    97  	// because setup will take care of those when bootstrapBuildTools returns.
    98  
    99  	defer os.Setenv("GOROOT", os.Getenv("GOROOT"))
   100  	os.Setenv("GOROOT", goroot_bootstrap)
   101  
   102  	defer os.Setenv("GOPATH", os.Getenv("GOPATH"))
   103  	os.Setenv("GOPATH", workspace)
   104  
   105  	defer os.Setenv("GOBIN", os.Getenv("GOBIN"))
   106  	os.Setenv("GOBIN", "")
   107  
   108  	os.Setenv("GOOS", "")
   109  	os.Setenv("GOHOSTOS", "")
   110  	os.Setenv("GOARCH", "")
   111  	os.Setenv("GOHOSTARCH", "")
   112  
   113  	// Run Go 1.4 to build binaries.
   114  	run(workspace, ShowOutput|CheckExit, pathf("%s/bin/go", goroot_bootstrap), "install", "-v", "bootstrap/...")
   115  
   116  	// Copy binaries into tool binary directory.
   117  	for _, name := range bootstrapDirs {
   118  		if !strings.Contains(name, "/") {
   119  			copyfile(pathf("%s/%s%s", tooldir, name, exe), pathf("%s/bin/%s%s", workspace, name, exe), writeExec)
   120  		}
   121  	}
   122  
   123  	xprintf("\n")
   124  }
   125  
   126  func bootstrapFixImports(text, srcFile string) string {
   127  	lines := strings.SplitAfter(text, "\n")
   128  	inBlock := false
   129  	for i, line := range lines {
   130  		if strings.HasPrefix(line, "import (") {
   131  			inBlock = true
   132  			continue
   133  		}
   134  		if inBlock && strings.HasPrefix(line, ")") {
   135  			inBlock = false
   136  			continue
   137  		}
   138  		if strings.HasPrefix(line, `import "`) || strings.HasPrefix(line, `import . "`) ||
   139  			inBlock && (strings.HasPrefix(line, "\t\"") || strings.HasPrefix(line, "\t. \"")) {
   140  			lines[i] = strings.Replace(line, `"cmd/`, `"bootstrap/`, -1)
   141  		}
   142  	}
   143  
   144  	lines[0] = "// Do not edit. Bootstrap copy of " + srcFile + "\n\n//line " + srcFile + ":1\n" + lines[0]
   145  
   146  	return strings.Join(lines, "")
   147  }