489 lines
17 KiB
Go
489 lines
17 KiB
Go
// Copyright 2021 Google Inc. All rights reserved.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package android
|
|
|
|
import (
|
|
"fmt"
|
|
"reflect"
|
|
"regexp"
|
|
"sort"
|
|
"strings"
|
|
|
|
"android/soong/bazel"
|
|
"android/soong/starlark_fmt"
|
|
|
|
"github.com/google/blueprint"
|
|
)
|
|
|
|
// BazelVarExporter is a collection of configuration variables that can be exported for use in Bazel rules
|
|
type BazelVarExporter interface {
|
|
// asBazel expands strings of configuration variables into their concrete values
|
|
asBazel(Config, ExportedStringVariables, ExportedStringListVariables, ExportedConfigDependingVariables) []bazelConstant
|
|
}
|
|
|
|
// ExportedVariables is a collection of interdependent configuration variables
|
|
type ExportedVariables struct {
|
|
// Maps containing toolchain variables that are independent of the
|
|
// environment variables of the build.
|
|
exportedStringVars ExportedStringVariables
|
|
exportedStringListVars ExportedStringListVariables
|
|
exportedStringListDictVars ExportedStringListDictVariables
|
|
|
|
exportedVariableReferenceDictVars ExportedVariableReferenceDictVariables
|
|
|
|
/// Maps containing variables that are dependent on the build config.
|
|
exportedConfigDependingVars ExportedConfigDependingVariables
|
|
|
|
pctx PackageContext
|
|
}
|
|
|
|
// NewExportedVariables creats an empty ExportedVariables struct with non-nil maps
|
|
func NewExportedVariables(pctx PackageContext) ExportedVariables {
|
|
return ExportedVariables{
|
|
exportedStringVars: ExportedStringVariables{},
|
|
exportedStringListVars: ExportedStringListVariables{},
|
|
exportedStringListDictVars: ExportedStringListDictVariables{},
|
|
exportedVariableReferenceDictVars: ExportedVariableReferenceDictVariables{},
|
|
exportedConfigDependingVars: ExportedConfigDependingVariables{},
|
|
pctx: pctx,
|
|
}
|
|
}
|
|
|
|
func (ev ExportedVariables) asBazel(config Config,
|
|
stringVars ExportedStringVariables, stringListVars ExportedStringListVariables, cfgDepVars ExportedConfigDependingVariables) []bazelConstant {
|
|
ret := []bazelConstant{}
|
|
ret = append(ret, ev.exportedStringVars.asBazel(config, stringVars, stringListVars, cfgDepVars)...)
|
|
ret = append(ret, ev.exportedStringListVars.asBazel(config, stringVars, stringListVars, cfgDepVars)...)
|
|
ret = append(ret, ev.exportedStringListDictVars.asBazel(config, stringVars, stringListVars, cfgDepVars)...)
|
|
// Note: ExportedVariableReferenceDictVars collections can only contain references to other variables and must be printed last
|
|
ret = append(ret, ev.exportedVariableReferenceDictVars.asBazel(config, stringVars, stringListVars, cfgDepVars)...)
|
|
return ret
|
|
}
|
|
|
|
// ExportStringStaticVariable declares a static string variable and exports it to
|
|
// Bazel's toolchain.
|
|
func (ev ExportedVariables) ExportStringStaticVariable(name string, value string) {
|
|
ev.pctx.StaticVariable(name, value)
|
|
ev.exportedStringVars.set(name, value)
|
|
}
|
|
|
|
// ExportStringListStaticVariable declares a static variable and exports it to
|
|
// Bazel's toolchain.
|
|
func (ev ExportedVariables) ExportStringListStaticVariable(name string, value []string) {
|
|
ev.pctx.StaticVariable(name, strings.Join(value, " "))
|
|
ev.exportedStringListVars.set(name, value)
|
|
}
|
|
|
|
// ExportVariableConfigMethod declares a variable whose value is evaluated at
|
|
// runtime via a function with access to the Config and exports it to Bazel's
|
|
// toolchain.
|
|
func (ev ExportedVariables) ExportVariableConfigMethod(name string, method interface{}) blueprint.Variable {
|
|
ev.exportedConfigDependingVars.set(name, method)
|
|
return ev.pctx.VariableConfigMethod(name, method)
|
|
}
|
|
|
|
// ExportSourcePathVariable declares a static "source path" variable and exports
|
|
// it to Bazel's toolchain.
|
|
func (ev ExportedVariables) ExportSourcePathVariable(name string, value string) {
|
|
ev.pctx.SourcePathVariable(name, value)
|
|
ev.exportedStringVars.set(name, value)
|
|
}
|
|
|
|
// ExportVariableFuncVariable declares a variable whose value is evaluated at
|
|
// runtime via a function and exports it to Bazel's toolchain.
|
|
func (ev ExportedVariables) ExportVariableFuncVariable(name string, f func() string) {
|
|
ev.exportedConfigDependingVars.set(name, func(config Config) string {
|
|
return f()
|
|
})
|
|
ev.pctx.VariableFunc(name, func(PackageVarContext) string {
|
|
return f()
|
|
})
|
|
}
|
|
|
|
// ExportString only exports a variable to Bazel, but does not declare it in Soong
|
|
func (ev ExportedVariables) ExportString(name string, value string) {
|
|
ev.exportedStringVars.set(name, value)
|
|
}
|
|
|
|
// ExportStringList only exports a variable to Bazel, but does not declare it in Soong
|
|
func (ev ExportedVariables) ExportStringList(name string, value []string) {
|
|
ev.exportedStringListVars.set(name, value)
|
|
}
|
|
|
|
// ExportStringListDict only exports a variable to Bazel, but does not declare it in Soong
|
|
func (ev ExportedVariables) ExportStringListDict(name string, value map[string][]string) {
|
|
ev.exportedStringListDictVars.set(name, value)
|
|
}
|
|
|
|
// ExportVariableReferenceDict only exports a variable to Bazel, but does not declare it in Soong
|
|
func (ev ExportedVariables) ExportVariableReferenceDict(name string, value map[string]string) {
|
|
ev.exportedVariableReferenceDictVars.set(name, value)
|
|
}
|
|
|
|
// ExportedConfigDependingVariables is a mapping of variable names to functions
|
|
// of type func(config Config) string which return the runtime-evaluated string
|
|
// value of a particular variable
|
|
type ExportedConfigDependingVariables map[string]interface{}
|
|
|
|
func (m ExportedConfigDependingVariables) set(k string, v interface{}) {
|
|
m[k] = v
|
|
}
|
|
|
|
// Ensure that string s has no invalid characters to be generated into the bzl file.
|
|
func validateCharacters(s string) string {
|
|
for _, c := range []string{`\n`, `"`, `\`} {
|
|
if strings.Contains(s, c) {
|
|
panic(fmt.Errorf("%s contains illegal character %s", s, c))
|
|
}
|
|
}
|
|
return s
|
|
}
|
|
|
|
type bazelConstant struct {
|
|
variableName string
|
|
internalDefinition string
|
|
sortLast bool
|
|
}
|
|
|
|
// ExportedStringVariables is a mapping of variable names to string values
|
|
type ExportedStringVariables map[string]string
|
|
|
|
func (m ExportedStringVariables) set(k string, v string) {
|
|
m[k] = v
|
|
}
|
|
|
|
func (m ExportedStringVariables) asBazel(config Config,
|
|
stringVars ExportedStringVariables, stringListVars ExportedStringListVariables, cfgDepVars ExportedConfigDependingVariables) []bazelConstant {
|
|
ret := make([]bazelConstant, 0, len(m))
|
|
for k, variableValue := range m {
|
|
expandedVar, err := expandVar(config, variableValue, stringVars, stringListVars, cfgDepVars)
|
|
if err != nil {
|
|
panic(fmt.Errorf("error expanding config variable %s: %s", k, err))
|
|
}
|
|
if len(expandedVar) > 1 {
|
|
panic(fmt.Errorf("%s expands to more than one string value: %s", variableValue, expandedVar))
|
|
}
|
|
ret = append(ret, bazelConstant{
|
|
variableName: k,
|
|
internalDefinition: fmt.Sprintf(`"%s"`, validateCharacters(expandedVar[0])),
|
|
})
|
|
}
|
|
return ret
|
|
}
|
|
|
|
// ExportedStringListVariables is a mapping of variable names to a list of strings
|
|
type ExportedStringListVariables map[string][]string
|
|
|
|
func (m ExportedStringListVariables) set(k string, v []string) {
|
|
m[k] = v
|
|
}
|
|
|
|
func (m ExportedStringListVariables) asBazel(config Config,
|
|
stringScope ExportedStringVariables, stringListScope ExportedStringListVariables,
|
|
exportedVars ExportedConfigDependingVariables) []bazelConstant {
|
|
ret := make([]bazelConstant, 0, len(m))
|
|
// For each exported variable, recursively expand elements in the variableValue
|
|
// list to ensure that interpolated variables are expanded according to their values
|
|
// in the variable scope.
|
|
for k, variableValue := range m {
|
|
var expandedVars []string
|
|
for _, v := range variableValue {
|
|
expandedVar, err := expandVar(config, v, stringScope, stringListScope, exportedVars)
|
|
if err != nil {
|
|
panic(fmt.Errorf("Error expanding config variable %s=%s: %s", k, v, err))
|
|
}
|
|
expandedVars = append(expandedVars, expandedVar...)
|
|
}
|
|
// Assign the list as a bzl-private variable; this variable will be exported
|
|
// out through a constants struct later.
|
|
ret = append(ret, bazelConstant{
|
|
variableName: k,
|
|
internalDefinition: starlark_fmt.PrintStringList(expandedVars, 0),
|
|
})
|
|
}
|
|
return ret
|
|
}
|
|
|
|
// ExportedStringListDictVariables is a mapping from variable names to a
|
|
// dictionary which maps keys to lists of strings
|
|
type ExportedStringListDictVariables map[string]map[string][]string
|
|
|
|
func (m ExportedStringListDictVariables) set(k string, v map[string][]string) {
|
|
m[k] = v
|
|
}
|
|
|
|
// Since dictionaries are not supported in Ninja, we do not expand variables for dictionaries
|
|
func (m ExportedStringListDictVariables) asBazel(_ Config, _ ExportedStringVariables,
|
|
_ ExportedStringListVariables, _ ExportedConfigDependingVariables) []bazelConstant {
|
|
ret := make([]bazelConstant, 0, len(m))
|
|
for k, dict := range m {
|
|
ret = append(ret, bazelConstant{
|
|
variableName: k,
|
|
internalDefinition: starlark_fmt.PrintStringListDict(dict, 0),
|
|
})
|
|
}
|
|
return ret
|
|
}
|
|
|
|
// ExportedVariableReferenceDictVariables is a mapping from variable names to a
|
|
// dictionary which references previously defined variables. This is used to
|
|
// create a Starlark output such as:
|
|
//
|
|
// string_var1 = "string1
|
|
// var_ref_dict_var1 = {
|
|
// "key1": string_var1
|
|
// }
|
|
//
|
|
// This type of variable collection must be expanded last so that it recognizes
|
|
// previously defined variables.
|
|
type ExportedVariableReferenceDictVariables map[string]map[string]string
|
|
|
|
func (m ExportedVariableReferenceDictVariables) set(k string, v map[string]string) {
|
|
m[k] = v
|
|
}
|
|
|
|
func (m ExportedVariableReferenceDictVariables) asBazel(_ Config, _ ExportedStringVariables,
|
|
_ ExportedStringListVariables, _ ExportedConfigDependingVariables) []bazelConstant {
|
|
ret := make([]bazelConstant, 0, len(m))
|
|
for n, dict := range m {
|
|
for k, v := range dict {
|
|
matches, err := variableReference(v)
|
|
if err != nil {
|
|
panic(err)
|
|
} else if !matches.matches {
|
|
panic(fmt.Errorf("Expected a variable reference, got %q", v))
|
|
} else if len(matches.fullVariableReference) != len(v) {
|
|
panic(fmt.Errorf("Expected only a variable reference, got %q", v))
|
|
}
|
|
dict[k] = "_" + matches.variable
|
|
}
|
|
ret = append(ret, bazelConstant{
|
|
variableName: n,
|
|
internalDefinition: starlark_fmt.PrintDict(dict, 0),
|
|
sortLast: true,
|
|
})
|
|
}
|
|
return ret
|
|
}
|
|
|
|
// BazelToolchainVars expands an ExportedVariables collection and returns a string
|
|
// of formatted Starlark variable definitions
|
|
func BazelToolchainVars(config Config, exportedVars ExportedVariables) string {
|
|
results := exportedVars.asBazel(
|
|
config,
|
|
exportedVars.exportedStringVars,
|
|
exportedVars.exportedStringListVars,
|
|
exportedVars.exportedConfigDependingVars,
|
|
)
|
|
|
|
sort.Slice(results, func(i, j int) bool {
|
|
if results[i].sortLast != results[j].sortLast {
|
|
return !results[i].sortLast
|
|
}
|
|
return results[i].variableName < results[j].variableName
|
|
})
|
|
|
|
definitions := make([]string, 0, len(results))
|
|
constants := make([]string, 0, len(results))
|
|
for _, b := range results {
|
|
definitions = append(definitions,
|
|
fmt.Sprintf("_%s = %s", b.variableName, b.internalDefinition))
|
|
constants = append(constants,
|
|
fmt.Sprintf("%[1]s%[2]s = _%[2]s,", starlark_fmt.Indention(1), b.variableName))
|
|
}
|
|
|
|
// Build the exported constants struct.
|
|
ret := bazel.GeneratedBazelFileWarning
|
|
ret += "\n\n"
|
|
ret += strings.Join(definitions, "\n\n")
|
|
ret += "\n\n"
|
|
ret += "constants = struct(\n"
|
|
ret += strings.Join(constants, "\n")
|
|
ret += "\n)"
|
|
|
|
return ret
|
|
}
|
|
|
|
type match struct {
|
|
matches bool
|
|
fullVariableReference string
|
|
variable string
|
|
}
|
|
|
|
func variableReference(input string) (match, error) {
|
|
// e.g. "${ExternalCflags}"
|
|
r := regexp.MustCompile(`\${(?:config\.)?([a-zA-Z0-9_]+)}`)
|
|
|
|
matches := r.FindStringSubmatch(input)
|
|
if len(matches) == 0 {
|
|
return match{}, nil
|
|
}
|
|
if len(matches) != 2 {
|
|
return match{}, fmt.Errorf("Expected to only match 1 subexpression in %s, got %d", input, len(matches)-1)
|
|
}
|
|
return match{
|
|
matches: true,
|
|
fullVariableReference: matches[0],
|
|
// Index 1 of FindStringSubmatch contains the subexpression match
|
|
// (variable name) of the capture group.
|
|
variable: matches[1],
|
|
}, nil
|
|
}
|
|
|
|
// expandVar recursively expand interpolated variables in the exportedVars scope.
|
|
//
|
|
// We're using a string slice to track the seen variables to avoid
|
|
// stackoverflow errors with infinite recursion. it's simpler to use a
|
|
// string slice than to handle a pass-by-referenced map, which would make it
|
|
// quite complex to track depth-first interpolations. It's also unlikely the
|
|
// interpolation stacks are deep (n > 1).
|
|
func expandVar(config Config, toExpand string, stringScope ExportedStringVariables,
|
|
stringListScope ExportedStringListVariables, exportedVars ExportedConfigDependingVariables) ([]string, error) {
|
|
|
|
// Internal recursive function.
|
|
var expandVarInternal func(string, map[string]bool) (string, error)
|
|
expandVarInternal = func(toExpand string, seenVars map[string]bool) (string, error) {
|
|
var ret string
|
|
remainingString := toExpand
|
|
for len(remainingString) > 0 {
|
|
matches, err := variableReference(remainingString)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if !matches.matches {
|
|
return ret + remainingString, nil
|
|
}
|
|
matchIndex := strings.Index(remainingString, matches.fullVariableReference)
|
|
ret += remainingString[:matchIndex]
|
|
remainingString = remainingString[matchIndex+len(matches.fullVariableReference):]
|
|
|
|
variable := matches.variable
|
|
// toExpand contains a variable.
|
|
if _, ok := seenVars[variable]; ok {
|
|
return ret, fmt.Errorf(
|
|
"Unbounded recursive interpolation of variable: %s", variable)
|
|
}
|
|
// A map is passed-by-reference. Create a new map for
|
|
// this scope to prevent variables seen in one depth-first expansion
|
|
// to be also treated as "seen" in other depth-first traversals.
|
|
newSeenVars := map[string]bool{}
|
|
for k := range seenVars {
|
|
newSeenVars[k] = true
|
|
}
|
|
newSeenVars[variable] = true
|
|
if unexpandedVars, ok := stringListScope[variable]; ok {
|
|
expandedVars := []string{}
|
|
for _, unexpandedVar := range unexpandedVars {
|
|
expandedVar, err := expandVarInternal(unexpandedVar, newSeenVars)
|
|
if err != nil {
|
|
return ret, err
|
|
}
|
|
expandedVars = append(expandedVars, expandedVar)
|
|
}
|
|
ret += strings.Join(expandedVars, " ")
|
|
} else if unexpandedVar, ok := stringScope[variable]; ok {
|
|
expandedVar, err := expandVarInternal(unexpandedVar, newSeenVars)
|
|
if err != nil {
|
|
return ret, err
|
|
}
|
|
ret += expandedVar
|
|
} else if unevaluatedVar, ok := exportedVars[variable]; ok {
|
|
evalFunc := reflect.ValueOf(unevaluatedVar)
|
|
validateVariableMethod(variable, evalFunc)
|
|
evaluatedResult := evalFunc.Call([]reflect.Value{reflect.ValueOf(config)})
|
|
evaluatedValue := evaluatedResult[0].Interface().(string)
|
|
expandedVar, err := expandVarInternal(evaluatedValue, newSeenVars)
|
|
if err != nil {
|
|
return ret, err
|
|
}
|
|
ret += expandedVar
|
|
} else {
|
|
return "", fmt.Errorf("Unbound config variable %s", variable)
|
|
}
|
|
}
|
|
return ret, nil
|
|
}
|
|
var ret []string
|
|
stringFields := splitStringKeepingQuotedSubstring(toExpand, ' ')
|
|
for _, v := range stringFields {
|
|
val, err := expandVarInternal(v, map[string]bool{})
|
|
if err != nil {
|
|
return ret, err
|
|
}
|
|
ret = append(ret, val)
|
|
}
|
|
|
|
return ret, nil
|
|
}
|
|
|
|
// splitStringKeepingQuotedSubstring splits a string on a provided separator,
|
|
// but it will not split substrings inside unescaped double quotes. If the double
|
|
// quotes are escaped, then the returned string will only include the quote, and
|
|
// not the escape.
|
|
func splitStringKeepingQuotedSubstring(s string, delimiter byte) []string {
|
|
var ret []string
|
|
quote := byte('"')
|
|
|
|
var substring []byte
|
|
quoted := false
|
|
escaped := false
|
|
|
|
for i := range s {
|
|
if !quoted && s[i] == delimiter {
|
|
ret = append(ret, string(substring))
|
|
substring = []byte{}
|
|
continue
|
|
}
|
|
|
|
characterIsEscape := i < len(s)-1 && s[i] == '\\' && s[i+1] == quote
|
|
if characterIsEscape {
|
|
escaped = true
|
|
continue
|
|
}
|
|
|
|
if s[i] == quote {
|
|
if !escaped {
|
|
quoted = !quoted
|
|
}
|
|
escaped = false
|
|
}
|
|
|
|
substring = append(substring, s[i])
|
|
}
|
|
|
|
ret = append(ret, string(substring))
|
|
|
|
return ret
|
|
}
|
|
|
|
func validateVariableMethod(name string, methodValue reflect.Value) {
|
|
methodType := methodValue.Type()
|
|
if methodType.Kind() != reflect.Func {
|
|
panic(fmt.Errorf("method given for variable %s is not a function",
|
|
name))
|
|
}
|
|
if n := methodType.NumIn(); n != 1 {
|
|
panic(fmt.Errorf("method for variable %s has %d inputs (should be 1)",
|
|
name, n))
|
|
}
|
|
if n := methodType.NumOut(); n != 1 {
|
|
panic(fmt.Errorf("method for variable %s has %d outputs (should be 1)",
|
|
name, n))
|
|
}
|
|
if kind := methodType.Out(0).Kind(); kind != reflect.String {
|
|
panic(fmt.Errorf("method for variable %s does not return a string",
|
|
name))
|
|
}
|
|
}
|