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-rw-r--r--binapi_generator/generator.go627
1 files changed, 627 insertions, 0 deletions
diff --git a/binapi_generator/generator.go b/binapi_generator/generator.go
new file mode 100644
index 0000000..0a66b37
--- /dev/null
+++ b/binapi_generator/generator.go
@@ -0,0 +1,627 @@
+// Copyright (c) 2017 Cisco and/or its affiliates.
+//
+// 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 main
+
+import (
+ "bufio"
+ "bytes"
+ "encoding/json"
+ "errors"
+ "flag"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "os"
+ "os/exec"
+ "path/filepath"
+ "strings"
+ "time"
+ "unicode"
+
+ "github.com/bennyscetbun/jsongo"
+)
+
+// MessageType represents the type of a VPP message.
+type messageType int
+
+const (
+ requestMessage messageType = iota // VPP request message
+ replyMessage // VPP reply message
+ otherMessage // other VPP message
+)
+
+const (
+ apiImportPath = "gerrit.fd.io/r/govpp/api" // import path of the govpp API
+ inputFileExt = ".json" // filename extension of files that should be processed as the input
+)
+
+// context is a structure storing details of a particular code generation task
+type context struct {
+ inputFile string // file with input JSON data
+ inputBuff *bytes.Buffer // contents of the input file
+ inputLine int // currently processed line in the input file
+ outputFile string // file with output data
+ packageName string // name of the Go package being generated
+ packageDir string // directory where the package source files are located
+ types map[string]string // map of the VPP typedef names to generated Go typedef names
+}
+
+func main() {
+ inputFile := flag.String("input-file", "", "Input JSON file.")
+ inputDir := flag.String("input-dir", ".", "Input directory with JSON files.")
+ outputDir := flag.String("output-dir", ".", "Output directory where package folders will be generated.")
+ flag.Parse()
+
+ if *inputFile == "" && *inputDir == "" {
+ fmt.Fprintln(os.Stderr, "ERROR: input-file or input-dir must be specified")
+ os.Exit(1)
+ }
+
+ var err, tmpErr error
+ if *inputFile != "" {
+ // process one input file
+ err = generateFromFile(*inputFile, *outputDir)
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "ERROR: code generation from %s failed: %v\n", *inputFile, err)
+ }
+ } else {
+ // process all files in specified directory
+ files, err := getInputFiles(*inputDir)
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "ERROR: code generation failed: %v\n", err)
+ }
+ for _, file := range files {
+ tmpErr = generateFromFile(file, *outputDir)
+ if tmpErr != nil {
+ fmt.Fprintf(os.Stderr, "ERROR: code generation from %s failed: %v\n", file, err)
+ err = tmpErr // remember that the error occurred
+ }
+ }
+ }
+ if err != nil {
+ os.Exit(1)
+ }
+}
+
+// getInputFiles returns all input files located in specified directory
+func getInputFiles(inputDir string) ([]string, error) {
+ files, err := ioutil.ReadDir(inputDir)
+ if err != nil {
+ return nil, fmt.Errorf("reading directory %s failed: %v", inputDir, err)
+ }
+ res := make([]string, 0)
+ for _, f := range files {
+ if strings.HasSuffix(f.Name(), inputFileExt) {
+ res = append(res, inputDir+"/"+f.Name())
+ }
+ }
+ return res, nil
+}
+
+// generateFromFile generates Go bindings from one input JSON file
+func generateFromFile(inputFile, outputDir string) error {
+ ctx, err := getContext(inputFile, outputDir)
+ if err != nil {
+ return err
+ }
+ // read the file
+ inputData, err := readFile(inputFile)
+ if err != nil {
+ return err
+ }
+ ctx.inputBuff = bytes.NewBuffer(inputData)
+
+ // parse JSON
+ jsonRoot, err := parseJSON(inputData)
+ if err != nil {
+ return err
+ }
+
+ // create output directory
+ err = os.MkdirAll(ctx.packageDir, 0777)
+ if err != nil {
+ return fmt.Errorf("creating output directory %s failed: %v", ctx.packageDir, err)
+ }
+
+ // open output file
+ f, err := os.Create(ctx.outputFile)
+ defer f.Close()
+ if err != nil {
+ return fmt.Errorf("creating output file %s failed: %v", ctx.outputFile, err)
+ }
+ w := bufio.NewWriter(f)
+
+ // generate Go package code
+ err = generatePackage(ctx, w, jsonRoot)
+ if err != nil {
+ return err
+ }
+
+ // go format the output file (non-fatal if fails)
+ exec.Command("gofmt", "-w", ctx.outputFile).Run()
+
+ return nil
+}
+
+// getContext returns context details of the code generation task
+func getContext(inputFile, outputDir string) (*context, error) {
+ if !strings.HasSuffix(inputFile, inputFileExt) {
+ return nil, fmt.Errorf("invalid input file name %s", inputFile)
+ }
+
+ ctx := &context{inputFile: inputFile}
+ inputFileName := filepath.Base(inputFile)
+
+ ctx.packageName = inputFileName[0:strings.Index(inputFileName, ".")]
+ if ctx.packageName == "interface" {
+ // 'interface' cannot be a package name, it is a go keyword
+ ctx.packageName = "interfaces"
+ }
+
+ ctx.packageDir = outputDir + "/" + ctx.packageName + "/"
+ ctx.outputFile = ctx.packageDir + ctx.packageName + ".go"
+
+ return ctx, nil
+}
+
+// readFile reads content of a file into memory
+func readFile(inputFile string) ([]byte, error) {
+
+ inputData, err := ioutil.ReadFile(inputFile)
+
+ if err != nil {
+ return nil, fmt.Errorf("reading data from file failed: %v", err)
+ }
+
+ return inputData, nil
+}
+
+// parseJSON parses a JSON data into an in-memory tree
+func parseJSON(inputData []byte) (*jsongo.JSONNode, error) {
+ root := jsongo.JSONNode{}
+
+ err := json.Unmarshal(inputData, &root)
+ if err != nil {
+ return nil, fmt.Errorf("JSON unmarshall failed: %v", err)
+ }
+
+ return &root, nil
+
+}
+
+// generatePackage generates Go code of a package from provided JSON
+func generatePackage(ctx *context, w *bufio.Writer, jsonRoot *jsongo.JSONNode) error {
+ // generate file header
+ generatePackageHeader(ctx, w, jsonRoot)
+
+ // generate data types
+ ctx.types = make(map[string]string)
+ types := jsonRoot.Map("types")
+ for i := 0; i < types.Len(); i++ {
+ typ := types.At(i)
+ err := generateMessage(ctx, w, typ, true)
+ if err != nil {
+ return err
+ }
+ }
+
+ // generate messages
+ messages := jsonRoot.Map("messages")
+ for i := 0; i < messages.Len(); i++ {
+ msg := messages.At(i)
+ err := generateMessage(ctx, w, msg, false)
+ if err != nil {
+ return err
+ }
+ }
+
+ // flush the data:
+ err := w.Flush()
+ if err != nil {
+ return fmt.Errorf("flushing data to %s failed: %v", ctx.outputFile, err)
+ }
+
+ return nil
+}
+
+// generateMessage generates Go code of one VPP message encoded in JSON into provided writer
+func generateMessage(ctx *context, w io.Writer, msg *jsongo.JSONNode, isType bool) error {
+ if msg.Len() == 0 || msg.At(0).GetType() != jsongo.TypeValue {
+ return errors.New("invalid JSON for message specified")
+ }
+
+ msgName, ok := msg.At(0).Get().(string)
+ if !ok {
+ return fmt.Errorf("invalid JSON for message specified, message name is %T, not a string", msg.At(0).Get())
+ }
+ structName := camelCaseName(strings.Title(msgName))
+
+ // generate struct fields into the slice & determine message type
+ fields := make([]string, 0)
+ msgType := otherMessage
+ for j := 0; j < msg.Len(); j++ {
+ if jsongo.TypeArray == msg.At(j).GetType() {
+ fld := msg.At(j)
+ err := processMessageField(ctx, &fields, fld)
+ if err != nil {
+ return err
+ }
+ // determine whether ths is a request / reply / other message
+ if j == 2 {
+ fieldName, ok := fld.At(1).Get().(string)
+ if ok {
+ if fieldName == "client_index" {
+ msgType = requestMessage
+ } else if fieldName == "context" {
+ msgType = replyMessage
+ } else {
+ msgType = otherMessage
+ }
+ }
+ }
+ }
+ }
+
+ // generate struct comment
+ generateMessageComment(ctx, w, structName, msgName, isType)
+
+ // generate struct header
+ fmt.Fprintln(w, "type", structName, "struct {")
+
+ // print out the fields
+ for _, field := range fields {
+ fmt.Fprintln(w, field)
+ }
+
+ // generate end of the struct
+ fmt.Fprintln(w, "}")
+
+ // generate name getter
+ if isType {
+ generateTypeNameGetter(w, structName, msgName)
+ } else {
+ generateMessageNameGetter(w, structName, msgName)
+ }
+
+ // generate message type getter method
+ if !isType {
+ generateMessageTypeGetter(w, structName, msgType)
+ }
+
+ // generate CRC getter
+ crcIf := msg.At(msg.Len() - 1).At("crc").Get()
+ if crc, ok := crcIf.(string); ok {
+ generateCrcGetter(w, structName, crc)
+ }
+
+ // generate message factory
+ if !isType {
+ generateMessageFactory(w, structName)
+ }
+
+ // if this is a type, save it in the map for later use
+ if isType {
+ ctx.types[fmt.Sprintf("vl_api_%s_t", msgName)] = structName
+ }
+
+ return nil
+}
+
+// processMessageField process JSON describing one message field into Go code emitted into provided slice of message fields
+func processMessageField(ctx *context, fields *[]string, fld *jsongo.JSONNode) error {
+ if fld.Len() < 2 || fld.At(0).GetType() != jsongo.TypeValue || fld.At(1).GetType() != jsongo.TypeValue {
+ return errors.New("invalid JSON for message field specified")
+ }
+ fieldVppType, ok := fld.At(0).Get().(string)
+ if !ok {
+ return fmt.Errorf("invalid JSON for message specified, field type is %T, not a string", fld.At(0).Get())
+ }
+ fieldName, ok := fld.At(1).Get().(string)
+ if !ok {
+ return fmt.Errorf("invalid JSON for message specified, field name is %T, not a string", fld.At(1).Get())
+ }
+
+ // skip internal fields
+ fieldNameLower := strings.ToLower(fieldName)
+ if fieldNameLower == "crc" || fieldNameLower == "_vl_msg_id" {
+ return nil
+ }
+ if len(*fields) == 0 && (fieldNameLower == "client_index" || fieldNameLower == "context") {
+ return nil
+ }
+
+ fieldName = strings.TrimPrefix(fieldName, "_")
+ fieldName = camelCaseName(strings.Title(fieldName))
+
+ fieldStr := ""
+ isArray := false
+ arraySize := 0
+
+ fieldStr += "\t" + fieldName + " "
+ if fld.Len() > 2 {
+ isArray = true
+ arraySize = int(fld.At(2).Get().(float64))
+ fieldStr += "[]"
+ }
+
+ dataType := translateVppType(ctx, fieldVppType, isArray)
+ fieldStr += dataType
+
+ if isArray {
+ if arraySize == 0 {
+ // variable sized array
+ if fld.Len() > 3 {
+ // array size is specified by another field
+ arraySizeField := string(fld.At(3).Get().(string))
+ arraySizeField = camelCaseName(strings.Title(arraySizeField))
+ // find & update the field that specifies the array size
+ for i, f := range *fields {
+ if strings.Contains(f, fmt.Sprintf("\t%s ", arraySizeField)) {
+ (*fields)[i] += fmt.Sprintf("\t`struc:\"sizeof=%s\"`", fieldName)
+ }
+ }
+ }
+ } else {
+ // fixed size array
+ fieldStr += fmt.Sprintf("\t`struc:\"[%d]%s\"`", arraySize, dataType)
+ }
+ }
+
+ *fields = append(*fields, fieldStr)
+ return nil
+}
+
+// generatePackageHeader generates package header into provider writer
+func generatePackageHeader(ctx *context, w io.Writer, rootNode *jsongo.JSONNode) {
+ fmt.Fprintln(w, "// Package "+ctx.packageName+" represents the VPP binary API of the '"+ctx.packageName+"' VPP module.")
+ fmt.Fprintln(w, "// DO NOT EDIT. Generated from '"+ctx.inputFile+"' on "+time.Now().Format(time.RFC1123)+".")
+
+ fmt.Fprintln(w, "package "+ctx.packageName)
+
+ fmt.Fprintln(w, "import \""+apiImportPath+"\"")
+
+ fmt.Fprintln(w)
+ fmt.Fprintln(w, "// VlApiVersion contains version of the API.")
+ vlAPIVersion := rootNode.Map("vl_api_version")
+ if vlAPIVersion != nil {
+ fmt.Fprintln(w, "const VlAPIVersion = ", vlAPIVersion.Get())
+ }
+ fmt.Fprintln(w)
+}
+
+// generateMessageComment generates comment for a message into provider writer
+func generateMessageComment(ctx *context, w io.Writer, structName string, msgName string, isType bool) {
+ fmt.Fprintln(w)
+ if isType {
+ fmt.Fprintln(w, "// "+structName+" represents the VPP binary API data type '"+msgName+"'.")
+ } else {
+ fmt.Fprintln(w, "// "+structName+" represents the VPP binary API message '"+msgName+"'.")
+ }
+
+ // print out the source of the generated message - the JSON
+ msgFound := false
+ for {
+ lineBuff, err := ctx.inputBuff.ReadBytes('\n')
+ if err != nil {
+ break
+ }
+ ctx.inputLine++
+ line := string(lineBuff)
+
+ if !msgFound {
+ if strings.Contains(line, msgName) {
+ fmt.Fprintf(w, "// Generated from '%s', line %d:\n", ctx.inputFile, ctx.inputLine)
+ fmt.Fprintln(w, "//")
+ fmt.Fprint(w, "//", line)
+ msgFound = true
+ }
+ } else {
+ fmt.Fprint(w, "//", line)
+ if len(strings.Trim(line, " ")) < 4 {
+ break // end of the message in JSON
+ }
+ }
+ }
+ fmt.Fprintln(w, "//")
+}
+
+// generateMessageNameGetter generates getter for original VPP message name into the provider writer
+func generateMessageNameGetter(w io.Writer, structName string, msgName string) {
+ fmt.Fprintln(w, "func (*"+structName+") GetMessageName() string {")
+ fmt.Fprintln(w, "\treturn \""+msgName+"\"")
+ fmt.Fprintln(w, "}")
+}
+
+// generateTypeNameGetter generates getter for original VPP type name into the provider writer
+func generateTypeNameGetter(w io.Writer, structName string, msgName string) {
+ fmt.Fprintln(w, "func (*"+structName+") GetTypeName() string {")
+ fmt.Fprintln(w, "\treturn \""+msgName+"\"")
+ fmt.Fprintln(w, "}")
+}
+
+// generateMessageTypeGetter generates message factory for the generated message into the provider writer
+func generateMessageTypeGetter(w io.Writer, structName string, msgType messageType) {
+ fmt.Fprintln(w, "func (*"+structName+") GetMessageType() api.MessageType {")
+ if msgType == requestMessage {
+ fmt.Fprintln(w, "\treturn api.RequestMessage")
+ } else if msgType == replyMessage {
+ fmt.Fprintln(w, "\treturn api.ReplyMessage")
+ } else {
+ fmt.Fprintln(w, "\treturn api.OtherMessage")
+ }
+ fmt.Fprintln(w, "}")
+}
+
+// generateCrcGetter generates getter for CRC checksum of the message definition into the provider writer
+func generateCrcGetter(w io.Writer, structName string, crc string) {
+ crc = strings.TrimPrefix(crc, "0x")
+ fmt.Fprintln(w, "func (*"+structName+") GetCrcString() string {")
+ fmt.Fprintln(w, "\treturn \""+crc+"\"")
+ fmt.Fprintln(w, "}")
+}
+
+// generateMessageFactory generates message factory for the generated message into the provider writer
+func generateMessageFactory(w io.Writer, structName string) {
+ fmt.Fprintln(w, "func New"+structName+"() api.Message {")
+ fmt.Fprintln(w, "\treturn &"+structName+"{}")
+ fmt.Fprintln(w, "}")
+}
+
+// translateVppType translates the VPP data type into Go data type
+func translateVppType(ctx *context, vppType string, isArray bool) string {
+ // basic types
+ switch vppType {
+ case "u8":
+ if isArray {
+ return "byte"
+ }
+ return "uint8"
+ case "i8":
+ return "int8"
+ case "u16":
+ return "uint16"
+ case "i16":
+ return "int16"
+ case "u32":
+ return "uint32"
+ case "i32":
+ return "int32"
+ case "u64":
+ return "uint64"
+ case "i64":
+ return "int64"
+ case "f64":
+ return "float64"
+ }
+
+ // typedefs
+ typ, ok := ctx.types[vppType]
+ if ok {
+ return typ
+ }
+
+ panic(fmt.Sprintf("Unknown VPP type %s", vppType))
+}
+
+// camelCaseName returns correct name identifier (camelCase).
+func camelCaseName(name string) (should string) {
+ // Fast path for simple cases: "_" and all lowercase.
+ if name == "_" {
+ return name
+ }
+ allLower := true
+ for _, r := range name {
+ if !unicode.IsLower(r) {
+ allLower = false
+ break
+ }
+ }
+ if allLower {
+ return name
+ }
+
+ // Split camelCase at any lower->upper transition, and split on underscores.
+ // Check each word for common initialisms.
+ runes := []rune(name)
+ w, i := 0, 0 // index of start of word, scan
+ for i+1 <= len(runes) {
+ eow := false // whether we hit the end of a word
+ if i+1 == len(runes) {
+ eow = true
+ } else if runes[i+1] == '_' {
+ // underscore; shift the remainder forward over any run of underscores
+ eow = true
+ n := 1
+ for i+n+1 < len(runes) && runes[i+n+1] == '_' {
+ n++
+ }
+
+ // Leave at most one underscore if the underscore is between two digits
+ if i+n+1 < len(runes) && unicode.IsDigit(runes[i]) && unicode.IsDigit(runes[i+n+1]) {
+ n--
+ }
+
+ copy(runes[i+1:], runes[i+n+1:])
+ runes = runes[:len(runes)-n]
+ } else if unicode.IsLower(runes[i]) && !unicode.IsLower(runes[i+1]) {
+ // lower->non-lower
+ eow = true
+ }
+ i++
+ if !eow {
+ continue
+ }
+
+ // [w,i) is a word.
+ word := string(runes[w:i])
+ if u := strings.ToUpper(word); commonInitialisms[u] {
+ // Keep consistent case, which is lowercase only at the start.
+ if w == 0 && unicode.IsLower(runes[w]) {
+ u = strings.ToLower(u)
+ }
+ // All the common initialisms are ASCII,
+ // so we can replace the bytes exactly.
+ copy(runes[w:], []rune(u))
+ } else if w > 0 && strings.ToLower(word) == word {
+ // already all lowercase, and not the first word, so uppercase the first character.
+ runes[w] = unicode.ToUpper(runes[w])
+ }
+ w = i
+ }
+ return string(runes)
+}
+
+// commonInitialisms is a set of common initialisms that need to stay in upper case.
+var commonInitialisms = map[string]bool{
+ "ACL": true,
+ "API": true,
+ "ASCII": true,
+ "CPU": true,
+ "CSS": true,
+ "DNS": true,
+ "EOF": true,
+ "GUID": true,
+ "HTML": true,
+ "HTTP": true,
+ "HTTPS": true,
+ "ID": true,
+ "IP": true,
+ "ICMP": true,
+ "JSON": true,
+ "LHS": true,
+ "QPS": true,
+ "RAM": true,
+ "RHS": true,
+ "RPC": true,
+ "SLA": true,
+ "SMTP": true,
+ "SQL": true,
+ "SSH": true,
+ "TCP": true,
+ "TLS": true,
+ "TTL": true,
+ "UDP": true,
+ "UI": true,
+ "UID": true,
+ "UUID": true,
+ "URI": true,
+ "URL": true,
+ "UTF8": true,
+ "VM": true,
+ "XML": true,
+ "XMPP": true,
+ "XSRF": true,
+ "XSS": true,
+}