exec.go - platform/build/kati - Gitiles

 package main

 import (
 	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
 	"syscall"
 	"time"
 )

 type Executor struct {
 	rules         map[string]*Rule
 	implicitRules []*Rule
 	suffixRules   map[string][]*Rule
 	firstRule     *Rule
 }

 func newExecutor() *Executor {
 	return &Executor{
 		rules:       make(map[string]*Rule),
 		suffixRules: make(map[string][]*Rule),
 	}
 }

 // TODO(ukai): use time.Time?
 func getTimestamp(filename string) int64 {
 	st, err := os.Stat(filename)
 	if err != nil {
 		return -2
 	}
 	return st.ModTime().Unix()
 }

 func (ex *Executor) runCommands(cmds []string, output string) error {
 Loop:
 	for _, cmd := range cmds {
 		echo := true
 		ignoreErr := false
 		for {
 			cmd = strings.TrimLeft(cmd, " \t")
 			if cmd == "" {
 				continue Loop
 			}
 			switch cmd[0] {
 			case '@':
 				echo = false
 				cmd = cmd[1:]
 				continue
 			case '-':
 				ignoreErr = true
 				cmd = cmd[1:]
 				continue
 			}
 			break
 		}
 		if echo {
 			fmt.Printf("%s\n", cmd)
 		}
 		if dryRunFlag {
 			continue
 		}

 		args := []string{"/bin/sh", "-c", cmd}
 		cmd := exec.Cmd{
 			Path: args[0],
 			Args: args,
 		}
 		out, err := cmd.CombinedOutput()
 		exit := 0
 		if err != nil {
 			exit = 1
 			if err, ok := err.(*exec.ExitError); ok {
 				if w, ok := err.ProcessState.Sys().(syscall.WaitStatus); ok {
 					exit = w.ExitStatus()
 				}
 			} else {
 				return err
 			}
 		}
 		fmt.Printf("%s", out)
 		if exit != 0 {
 			if ignoreErr {
 				fmt.Printf("[%s] Error %d (ignored)\n", output, exit)
 				continue
 			}
 			return fmt.Errorf("command failed: %q. Error %d", cmd, exit)
 		}
 	}
 	return nil
 }

 func replaceSuffix(s string, newsuf string) string {
 	// TODO: Factor out the logic around suffix rules and use
 	// it from substitution references.
 	// http://www.gnu.org/software/make/manual/make.html#Substitution-Refs
 	return fmt.Sprintf("%s.%s", stripExt(s), newsuf)
 }

 func (ex *Executor) canPickImplicitRule(rule *Rule, output string) bool {
 	outputPattern := rule.outputPatterns[0]
 	if !matchPattern(outputPattern, output) {
 		return false
 	}
 	for _, input := range rule.inputs {
 		input = substPattern(outputPattern, input, output)
 		if !exists(input) {
 			return false
 		}
 	}
 	return true
 }

 func (ex *Executor) pickRule(output string) (*Rule, bool) {
 	rule, present := ex.rules[output]
 	if present {
 		return rule, true
 	}

 	for _, rule := range ex.implicitRules {
 		if ex.canPickImplicitRule(rule, output) {
 			return rule, true
 		}
 	}

 	outputSuffix := filepath.Ext(output)
 	if len(outputSuffix) > 0 && outputSuffix[0] == '.' {
 		rules, present := ex.suffixRules[outputSuffix[1:]]
 		if present {
 			for _, rule := range rules {
 				if len(rule.inputs) != 1 {
 					panic(fmt.Sprintf("unexpected number of input for a suffix rule (%d)", len(rule.inputs)))
 				}
 				if exists(replaceSuffix(output, rule.inputs[0])) {
 					return rule, true
 				}
 			}
 		}
 	}

 	return nil, false
 }

 func (ex *Executor) build(vars *VarTab, output string) (int64, error) {
 	Log("Building: %s", output)
 	outputTs := getTimestamp(output)

 	rule, present := ex.pickRule(output)
 	if !present {
 		if outputTs >= 0 {
 			return outputTs, nil
 		}
 		return outputTs, fmt.Errorf("no rule to make target %q", output)
 	}
 	if rule.vars != nil {
 		vars = NewVarTab(vars)
 		for k, v := range rule.vars.m {
 			vars.Assign(k, v)
 		}
 	}

 	latest := int64(-1)
 	var actualInputs []string
 	for _, input := range rule.inputs {
 		if len(rule.outputPatterns) > 0 {
 			if len(rule.outputPatterns) > 1 {
 				panic("TODO: multiple output pattern is not supported yet")
 			}
 			input = substPattern(rule.outputPatterns[0], input, output)
 		} else if rule.isSuffixRule {
 			input = replaceSuffix(output, input)
 		}
 		actualInputs = append(actualInputs, input)

 		ts, err := ex.build(vars, input)
 		if err != nil {
 			return outputTs, err
 		}
 		if latest < ts {
 			latest = ts
 		}
 	}

 	for _, input := range rule.orderOnlyInputs {
 		if exists(input) {
 			continue
 		}
 		ts, err := ex.build(vars, input)
 		if err != nil {
 			return outputTs, err
 		}
 		if latest < ts {
 			latest = ts
 		}
 	}

 	if outputTs >= latest {
 		return outputTs, nil
 	}

 	localVars := NewVarTab(vars)
 	// automatic variables.
 	localVars.Assign("@", SimpleVar{value: output, origin: "automatic"})
 	if len(actualInputs) > 0 {
 		localVars.Assign("<", SimpleVar{
 			value:  actualInputs[0],
 			origin: "automatic",
 		})
 		localVars.Assign("^", SimpleVar{
 			value:  strings.Join(actualInputs, " "),
 			origin: "automatic",
 		})
 	}
 	ev := newEvaluator(localVars)
 	ev.filename = rule.filename
 	ev.lineno = rule.cmdLineno
 	var cmds []string
 	for _, cmd := range rule.cmds {
 		if strings.IndexByte(cmd, '$') < 0 {
 			// fast path.
 			cmds = append(cmds, cmd)
 			continue
 		}
 		ecmd := ev.evalExpr(cmd)
 		Log("build eval:%q => %q", cmd, ecmd)
 		cmds = append(cmds, strings.Split(ecmd, "\n")...)
 	}

 	err := ex.runCommands(cmds, output)
 	if err != nil {
 		return outputTs, err
 	}

 	outputTs = getTimestamp(output)
 	if outputTs < 0 {
 		outputTs = time.Now().Unix()
 	}
 	return outputTs, nil
 }

 func (ex *Executor) populateSuffixRule(rule *Rule, output string) bool {
 	if len(output) == 0 || output[0] != '.' {
 		return false
 	}
 	rest := output[1:]
 	dotIndex := strings.IndexByte(rest, '.')
 	// If there is only a single dot or the third dot, this is not a
 	// suffix rule.
 	if dotIndex < 0 || strings.IndexByte(rest[dotIndex+1:], '.') >= 0 {
 		return false
 	}

 	// This is a suffix rule.
 	inputSuffix := rest[:dotIndex]
 	outputSuffix := rest[dotIndex+1:]
 	r := &Rule{}
 	*r = *rule
 	r.inputs = []string{inputSuffix}
 	r.isSuffixRule = true
 	ex.suffixRules[outputSuffix] = append([]*Rule{r}, ex.suffixRules[outputSuffix]...)
 	return true
 }

 func (ex *Executor) populateExplicitRule(rule *Rule) {
 	for _, output := range rule.outputs {
 		isSuffixRule := ex.populateSuffixRule(rule, output)

 		if oldRule, present := ex.rules[output]; present {
 			if oldRule.vars != nil || rule.vars != nil {
 				oldRule.isDoubleColon = rule.isDoubleColon
 				switch {
 				case rule.vars == nil && oldRule.vars != nil:
 					rule.vars = oldRule.vars
 				case rule.vars != nil && oldRule.vars == nil:
 				case rule.vars != nil && oldRule.vars != nil:
 					// parent would be the same vars?
 					for k, v := range rule.vars.m {
 						oldRule.vars.m[k] = v
 					}
 					rule.vars = oldRule.vars
 				}
 			}
 			if oldRule.isDoubleColon != rule.isDoubleColon {
 				Error(rule.filename, rule.lineno, "*** target file %q has both : and :: entries.", output)
 			}
 			if len(oldRule.cmds) > 0 && len(rule.cmds) > 0 && !isSuffixRule && !rule.isDoubleColon {
 				Warn(rule.filename, rule.cmdLineno, "overriding commands for target %q", output)
 				Warn(oldRule.filename, oldRule.cmdLineno, "ignoring old commands for target %q", output)
 			}
 			r := &Rule{}
 			*r = *rule
 			if rule.isDoubleColon {
 				r.cmds = append(oldRule.cmds, r.cmds...)
 			}
 			r.inputs = append(r.inputs, oldRule.inputs...)
 			ex.rules[output] = r
 		} else {
 			ex.rules[output] = rule
 			if ex.firstRule == nil && !isSuffixRule {
 				ex.firstRule = rule
 			}
 		}
 	}
 }

 func (ex *Executor) populateImplicitRule(rule *Rule) {
 	for _, outputPattern := range rule.outputPatterns {
 		r := &Rule{}
 		*r = *rule
 		r.outputPatterns = []string{outputPattern}
 		ex.implicitRules = append(ex.implicitRules, r)
 	}
 }

 func (ex *Executor) populateRules(er *EvalResult) {
 	for _, rule := range er.rules {
 		ex.populateExplicitRule(rule)

 		if len(rule.outputs) == 0 {
 			ex.populateImplicitRule(rule)
 		}
 	}

 	// Reverse the implicit rule for easier lookup.
 	for i, r := range ex.implicitRules {
 		if i >= len(ex.implicitRules)/2 {
 			break
 		}
 		j := len(ex.implicitRules) - i - 1
 		ex.implicitRules[i] = ex.implicitRules[j]
 		ex.implicitRules[j] = r
 	}
 }

 func (ex *Executor) exec(er *EvalResult, targets []string, vars *VarTab) error {
 	ex.populateRules(er)

 	if len(targets) == 0 {
 		if ex.firstRule == nil {
 			ErrorNoLocation("*** No targets.")
 		}
 		targets = append(targets, ex.firstRule.outputs[0])
 	}

 	for _, target := range targets {
 		_, err := ex.build(vars, target)
 		if err != nil {
 			return err
 		}
 	}
 	return nil
 }

 func Exec(er *EvalResult, targets []string, vars *VarTab) error {
 	ex := newExecutor()
 	return ex.exec(er, targets, vars)
 }
	package main

	import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"syscall"
	"time"
	)

	type Executor struct {
	rules map[string]*Rule
	implicitRules []*Rule
	suffixRules map[string][]*Rule
	firstRule *Rule
	}

	func newExecutor() *Executor {
	return &Executor{
	rules: make(map[string]*Rule),
	suffixRules: make(map[string][]*Rule),
	}
	}

	// TODO(ukai): use time.Time?
	func getTimestamp(filename string) int64 {
	st, err := os.Stat(filename)
	if err != nil {
	return -2
	}
	return st.ModTime().Unix()
	}

	func (ex *Executor) runCommands(cmds []string, output string) error {
	Loop:
	for _, cmd := range cmds {
	echo := true
	ignoreErr := false
	for {
	cmd = strings.TrimLeft(cmd, " \t")
	if cmd == "" {
	continue Loop
	}
	switch cmd[0] {
	case '@':
	echo = false
	cmd = cmd[1:]
	continue
	case '-':
	ignoreErr = true
	cmd = cmd[1:]
	continue
	}
	break
	}
	if echo {
	fmt.Printf("%s\n", cmd)
	}
	if dryRunFlag {
	continue
	}

	args := []string{"/bin/sh", "-c", cmd}
	cmd := exec.Cmd{
	Path: args[0],
	Args: args,
	}
	out, err := cmd.CombinedOutput()
	exit := 0
	if err != nil {
	exit = 1
	if err, ok := err.(*exec.ExitError); ok {
	if w, ok := err.ProcessState.Sys().(syscall.WaitStatus); ok {
	exit = w.ExitStatus()
	}
	} else {
	return err
	}
	}
	fmt.Printf("%s", out)
	if exit != 0 {
	if ignoreErr {
	fmt.Printf("[%s] Error %d (ignored)\n", output, exit)
	continue
	}
	return fmt.Errorf("command failed: %q. Error %d", cmd, exit)
	}
	}
	return nil
	}

	func replaceSuffix(s string, newsuf string) string {
	// TODO: Factor out the logic around suffix rules and use
	// it from substitution references.
	// http://www.gnu.org/software/make/manual/make.html#Substitution-Refs
	return fmt.Sprintf("%s.%s", stripExt(s), newsuf)
	}

	func (ex Executor) canPickImplicitRule(rule Rule, output string) bool {
	outputPattern := rule.outputPatterns[0]
	if !matchPattern(outputPattern, output) {
	return false
	}
	for _, input := range rule.inputs {
	input = substPattern(outputPattern, input, output)
	if !exists(input) {
	return false
	}
	}
	return true
	}

	func (ex Executor) pickRule(output string) (Rule, bool) {
	rule, present := ex.rules[output]
	if present {
	return rule, true
	}

	for _, rule := range ex.implicitRules {
	if ex.canPickImplicitRule(rule, output) {
	return rule, true
	}
	}

	outputSuffix := filepath.Ext(output)
	if len(outputSuffix) > 0 && outputSuffix[0] == '.' {
	rules, present := ex.suffixRules[outputSuffix[1:]]
	if present {
	for _, rule := range rules {
	if len(rule.inputs) != 1 {
	panic(fmt.Sprintf("unexpected number of input for a suffix rule (%d)", len(rule.inputs)))
	}
	if exists(replaceSuffix(output, rule.inputs[0])) {
	return rule, true
	}
	}
	}
	}

	return nil, false
	}

	func (ex Executor) build(vars VarTab, output string) (int64, error) {
	Log("Building: %s", output)
	outputTs := getTimestamp(output)

	rule, present := ex.pickRule(output)
	if !present {
	if outputTs >= 0 {
	return outputTs, nil
	}
	return outputTs, fmt.Errorf("no rule to make target %q", output)
	}
	if rule.vars != nil {
	vars = NewVarTab(vars)
	for k, v := range rule.vars.m {
	vars.Assign(k, v)
	}
	}

	latest := int64(-1)
	var actualInputs []string
	for _, input := range rule.inputs {
	if len(rule.outputPatterns) > 0 {
	if len(rule.outputPatterns) > 1 {
	panic("TODO: multiple output pattern is not supported yet")
	}
	input = substPattern(rule.outputPatterns[0], input, output)
	} else if rule.isSuffixRule {
	input = replaceSuffix(output, input)
	}
	actualInputs = append(actualInputs, input)

	ts, err := ex.build(vars, input)
	if err != nil {
	return outputTs, err
	}
	if latest < ts {
	latest = ts
	}
	}

	for _, input := range rule.orderOnlyInputs {
	if exists(input) {
	continue
	}
	ts, err := ex.build(vars, input)
	if err != nil {
	return outputTs, err
	}
	if latest < ts {
	latest = ts
	}
	}

	if outputTs >= latest {
	return outputTs, nil
	}

	localVars := NewVarTab(vars)
	// automatic variables.
	localVars.Assign("@", SimpleVar{value: output, origin: "automatic"})
	if len(actualInputs) > 0 {
	localVars.Assign("<", SimpleVar{
	value: actualInputs[0],
	origin: "automatic",
	})
	localVars.Assign("^", SimpleVar{
	value: strings.Join(actualInputs, " "),
	origin: "automatic",
	})
	}
	ev := newEvaluator(localVars)
	ev.filename = rule.filename
	ev.lineno = rule.cmdLineno
	var cmds []string
	for _, cmd := range rule.cmds {
	if strings.IndexByte(cmd, '$') < 0 {
	// fast path.
	cmds = append(cmds, cmd)
	continue
	}
	ecmd := ev.evalExpr(cmd)
	Log("build eval:%q => %q", cmd, ecmd)
	cmds = append(cmds, strings.Split(ecmd, "\n")...)
	}

	err := ex.runCommands(cmds, output)
	if err != nil {
	return outputTs, err
	}

	outputTs = getTimestamp(output)
	if outputTs < 0 {
	outputTs = time.Now().Unix()
	}
	return outputTs, nil
	}

	func (ex Executor) populateSuffixRule(rule Rule, output string) bool {
	if len(output) == 0 \|\| output[0] != '.' {
	return false
	}
	rest := output[1:]
	dotIndex := strings.IndexByte(rest, '.')
	// If there is only a single dot or the third dot, this is not a
	// suffix rule.
	if dotIndex < 0 \|\| strings.IndexByte(rest[dotIndex+1:], '.') >= 0 {
	return false
	}

	// This is a suffix rule.
	inputSuffix := rest[:dotIndex]
	outputSuffix := rest[dotIndex+1:]
	r := &Rule{}
	r = rule
	r.inputs = []string{inputSuffix}
	r.isSuffixRule = true
	ex.suffixRules[outputSuffix] = append([]*Rule{r}, ex.suffixRules[outputSuffix]...)
	return true
	}

	func (ex Executor) populateExplicitRule(rule Rule) {
	for _, output := range rule.outputs {
	isSuffixRule := ex.populateSuffixRule(rule, output)

	if oldRule, present := ex.rules[output]; present {
	if oldRule.vars != nil \|\| rule.vars != nil {
	oldRule.isDoubleColon = rule.isDoubleColon
	switch {
	case rule.vars == nil && oldRule.vars != nil:
	rule.vars = oldRule.vars
	case rule.vars != nil && oldRule.vars == nil:
	case rule.vars != nil && oldRule.vars != nil:
	// parent would be the same vars?
	for k, v := range rule.vars.m {
	oldRule.vars.m[k] = v
	}
	rule.vars = oldRule.vars
	}
	}
	if oldRule.isDoubleColon != rule.isDoubleColon {
	Error(rule.filename, rule.lineno, "*** target file %q has both : and :: entries.", output)
	}
	if len(oldRule.cmds) > 0 && len(rule.cmds) > 0 && !isSuffixRule && !rule.isDoubleColon {
	Warn(rule.filename, rule.cmdLineno, "overriding commands for target %q", output)
	Warn(oldRule.filename, oldRule.cmdLineno, "ignoring old commands for target %q", output)
	}
	r := &Rule{}
	r = rule
	if rule.isDoubleColon {
	r.cmds = append(oldRule.cmds, r.cmds...)
	}
	r.inputs = append(r.inputs, oldRule.inputs...)
	ex.rules[output] = r
	} else {
	ex.rules[output] = rule
	if ex.firstRule == nil && !isSuffixRule {
	ex.firstRule = rule
	}
	}
	}
	}

	func (ex Executor) populateImplicitRule(rule Rule) {
	for _, outputPattern := range rule.outputPatterns {
	r := &Rule{}
	r = rule
	r.outputPatterns = []string{outputPattern}
	ex.implicitRules = append(ex.implicitRules, r)
	}
	}

	func (ex Executor) populateRules(er EvalResult) {
	for _, rule := range er.rules {
	ex.populateExplicitRule(rule)

	if len(rule.outputs) == 0 {
	ex.populateImplicitRule(rule)
	}
	}

	// Reverse the implicit rule for easier lookup.
	for i, r := range ex.implicitRules {
	if i >= len(ex.implicitRules)/2 {
	break
	}
	j := len(ex.implicitRules) - i - 1
	ex.implicitRules[i] = ex.implicitRules[j]
	ex.implicitRules[j] = r
	}
	}

	func (ex Executor) exec(er EvalResult, targets []string, vars *VarTab) error {
	ex.populateRules(er)

	if len(targets) == 0 {
	if ex.firstRule == nil {
	ErrorNoLocation("*** No targets.")
	}
	targets = append(targets, ex.firstRule.outputs[0])
	}

	for _, target := range targets {
	_, err := ex.build(vars, target)
	if err != nil {
	return err
	}
	}
	return nil
	}

	func Exec(er EvalResult, targets []string, vars VarTab) error {
	ex := newExecutor()
	return ex.exec(er, targets, vars)
	}