github.com/sc0rp1us/gb@v0.4.1-0.20160319180011-4ba8cf1baa5a/importer/build.go

// Copyright 2011 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 importer

import (
	"bytes"
	"errors"
	"fmt"
	"go/token"
	"path/filepath"
	"strings"
	"unicode"
)

// importer is a private interface defined here so public *Importer
// types can be embedded in *Package with exposing them to the caller.
type importer interface {
	matchFile(path string, allTags map[string]bool) (match bool, data []byte, err error)
	match(name string, allTags map[string]bool) bool
}

// A Package describes the Go package found in a directory.
type Package struct {
	importer               // the importer context that loaded this package
	Dir           string   // directory containing package sources
	Name          string   // package name
	ImportPath    string   // import path of package ("" if unknown)
	Root          string   // root of Go tree where this package lives
	SrcRoot       string   // package source root directory ("" if unknown)
	PkgTargetRoot string   // architecture dependent install root directory ("" if unknown)
	Standard      bool     // package found in GOROOT
	AllTags       []string // tags that can influence file selection in this directory
	ConflictDir   string   // this directory shadows Dir in $GOPATH

	// Source files
	GoFiles        []string // .go source files (excluding CgoFiles, TestGoFiles, XTestGoFiles)
	CgoFiles       []string // .go source files that import "C"
	IgnoredGoFiles []string // .go source files ignored for this build
	CFiles         []string // .c source files
	CXXFiles       []string // .cc, .cpp and .cxx source files
	MFiles         []string // .m (Objective-C) source files
	HFiles         []string // .h, .hh, .hpp and .hxx source files
	SFiles         []string // .s source files
	SwigFiles      []string // .swig files
	SwigCXXFiles   []string // .swigcxx files
	SysoFiles      []string // .syso system object files to add to archive

	// Cgo directives
	CgoCFLAGS    []string // Cgo CFLAGS directives
	CgoCPPFLAGS  []string // Cgo CPPFLAGS directives
	CgoCXXFLAGS  []string // Cgo CXXFLAGS directives
	CgoLDFLAGS   []string // Cgo LDFLAGS directives
	CgoPkgConfig []string // Cgo pkg-config directives

	// Dependency information
	Imports   []string                    // imports from GoFiles, CgoFiles
	ImportPos map[string][]token.Position // line information for Imports

	// Test information
	TestGoFiles    []string                    // _test.go files in package
	TestImports    []string                    // imports from TestGoFiles
	TestImportPos  map[string][]token.Position // line information for TestImports
	XTestGoFiles   []string                    // _test.go files outside package
	XTestImports   []string                    // imports from XTestGoFiles
	XTestImportPos map[string][]token.Position // line information for XTestImports
}

// NoGoError is the error used by Import to describe a directory
// containing no buildable Go source files. (It may still contain
// test files, files hidden by build tags, and so on.)
type NoGoError struct {
	Dir string
}

func (e *NoGoError) Error() string {
	return "no buildable Go source files in " + e.Dir
}

// MultiplePackageError describes a directory containing
// multiple buildable Go source files for multiple packages.
type MultiplePackageError struct {
	Dir      string   // directory containing files
	Packages []string // package names found
	Files    []string // corresponding files: Files[i] declares package Packages[i]
}

func (e *MultiplePackageError) Error() string {
	// Error string limited to two entries for compatibility.
	return fmt.Sprintf("found packages %s (%s) and %s (%s) in %s", e.Packages[0], e.Files[0], e.Packages[1], e.Files[1], e.Dir)
}

// expandSrcDir expands any occurrence of ${SRCDIR}, making sure
// the result is safe for the shell.
func expandSrcDir(str string, srcdir string) (string, bool) {
	// "\" delimited paths cause safeCgoName to fail
	// so convert native paths with a different delimeter
	// to "/" before starting (eg: on windows).
	srcdir = filepath.ToSlash(srcdir)

	// Spaces are tolerated in ${SRCDIR}, but not anywhere else.
	chunks := strings.Split(str, "${SRCDIR}")
	if len(chunks) < 2 {
		return str, safeCgoName(str, false)
	}
	ok := true
	for _, chunk := range chunks {
		ok = ok && (chunk == "" || safeCgoName(chunk, false))
	}
	ok = ok && (srcdir == "" || safeCgoName(srcdir, true))
	res := strings.Join(chunks, srcdir)
	return res, ok && res != ""
}

// NOTE: $ is not safe for the shell, but it is allowed here because of linker options like -Wl,$ORIGIN.
// We never pass these arguments to a shell (just to programs we construct argv for), so this should be okay.
// See golang.org/issue/6038.
const safeString = "+-.,/0123456789=ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz:$"
const safeSpaces = " "

var safeBytes = []byte(safeSpaces + safeString)

func safeCgoName(s string, spaces bool) bool {
	if s == "" {
		return false
	}
	safe := safeBytes
	if !spaces {
		safe = safe[len(safeSpaces):]
	}
	for i := 0; i < len(s); i++ {
		if c := s[i]; c < 0x80 && bytes.IndexByte(safe, c) < 0 {
			return false
		}
	}
	return true
}

// splitQuoted splits the string s around each instance of one or more consecutive
// white space characters while taking into account quotes and escaping, and
// returns an array of substrings of s or an empty list if s contains only white space.
// Single quotes and double quotes are recognized to prevent splitting within the
// quoted region, and are removed from the resulting substrings. If a quote in s
// isn't closed err will be set and r will have the unclosed argument as the
// last element.  The backslash is used for escaping.
//
// For example, the following string:
//
//     a b:"c d" 'e''f'  "g\""
//
// Would be parsed as:
//
//     []string{"a", "b:c d", "ef", `g"`}
//
func splitQuoted(s string) (r []string, err error) {
	var args []string
	arg := make([]rune, len(s))
	escaped := false
	quoted := false
	quote := '\x00'
	i := 0
	for _, rune := range s {
		switch {
		case escaped:
			escaped = false
		case rune == '\\':
			escaped = true
			continue
		case quote != '\x00':
			if rune == quote {
				quote = '\x00'
				continue
			}
		case rune == '"' || rune == '\'':
			quoted = true
			quote = rune
			continue
		case unicode.IsSpace(rune):
			if quoted || i > 0 {
				quoted = false
				args = append(args, string(arg[:i]))
				i = 0
			}
			continue
		}
		arg[i] = rune
		i++
	}
	if quoted || i > 0 {
		args = append(args, string(arg[:i]))
	}
	if quote != 0 {
		err = errors.New("unclosed quote")
	} else if escaped {
		err = errors.New("unfinished escaping")
	}
	return args, err
}