Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tools/config_includer/generator.go

@@ -0,0 +1,142 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+	"text/template"
+	"text/template/parse"
+)
+
+func extractIncludes(tmpl *template.Template) []string {
+	var includes []string
+	for _, node := range tmpl.Root.Nodes {
+		if n, ok := node.(*parse.TemplateNode); ok {
+			includes = append(includes, n.Name)
+		}
+	}
+	return includes
+}
+
+func absolutePath(root, fn string) (string, error) {
+	pwd, err := filepath.Abs(fn)
+	if err != nil {
+		return "", fmt.Errorf("cannot determine absolute location of %q: %w", fn, err)
+	}
+	pwd, err = filepath.Rel(root, filepath.Dir(pwd))
+	if err != nil {
+		return "", fmt.Errorf("cannot determine location of %q relative to %q: %w", pwd, root, err)
+	}
+	return string(filepath.Separator) + pwd, nil
+}
+
+func main() {
+	// Estimate Telegraf root to be able to handle absolute paths
+	cwd, err := os.Getwd()
+	if err != nil {
+		log.Fatalf("Cannot get working directory: %v", err)
+	}
+	cwd, err = filepath.Abs(cwd)
+	if err != nil {
+		log.Fatalf("Cannot resolve working directory: %v", err)
+	}
+
+	var root string
+	idx := strings.LastIndex(cwd, filepath.FromSlash("/plugins/"))
+	if idx <= 0 {
+		log.Fatalln("Cannot determine include root!")
+	}
+	root = cwd[:idx]
+
+	var parent, inputFilename, outputFilename string
+	switch len(os.Args) {
+	case 1:
+		parent = strings.TrimPrefix(filepath.ToSlash(cwd[idx:]), "/plugins/")
+		parent = strings.ReplaceAll(parent, "/", ".")
+		inputFilename = "sample.conf.in"
+		outputFilename = "sample.conf"
+	case 2:
+		parent = os.Args[1]
+		inputFilename = "sample.conf.in"
+		outputFilename = "sample.conf"
+	case 3:
+		parent = os.Args[1]
+		inputFilename = os.Args[2]
+		if !strings.HasSuffix(inputFilename, ".in") {
+			log.Fatalf("Template filename %q does not have '.in' suffix!", inputFilename)
+		}
+		outputFilename = strings.TrimSuffix(inputFilename, ".in")
+	case 4:
+		parent = os.Args[1]
+		inputFilename = os.Args[2]
+		outputFilename = os.Args[3]
+	default:
+		log.Fatalln("Invalid number of arguments")
+	}
+
+	roottmpl := template.New(inputFilename)
+	known := make(map[string]bool)
+	inroot, err := absolutePath(root, inputFilename)
+	if err != nil {
+		log.Fatal(err)
+	}
+	unresolved := map[string]string{inputFilename: filepath.Join(inroot, inputFilename)}
+	for {
+		if len(unresolved) == 0 {
+			break
+		}
+
+		newUnresolved := make(map[string]string)
+		for name, fn := range unresolved {
+			if strings.HasPrefix(filepath.ToSlash(fn), "/") {
+				fn = filepath.Join(root, fn)
+			}
+
+			if known[name] {
+				// Include already resolved, skipping
+				continue
+			}
+
+			tmpl, err := template.ParseFiles(fn)
+			if err != nil {
+				log.Fatalf("Reading template %q failed: %v", fn, err)
+			}
+			known[name] = true
+			if _, err := roottmpl.AddParseTree(name, tmpl.Tree); err != nil {
+				log.Fatalf("Adding include %q failed: %v", fn, err)
+			}
+
+			// For relative paths we need to make it relative to the include
+			pwd, err := filepath.Abs(fn)
+			if err != nil {
+				log.Fatalf("Cannot determine absolute location of %q: %v", fn, err)
+			}
+			pwd, err = filepath.Rel(root, filepath.Dir(pwd))
+			if err != nil {
+				log.Fatalf("Cannot determine location of %q relative to %q: %v", pwd, root, err)
+			}
+			pwd = string(filepath.Separator) + pwd
+			for _, iname := range extractIncludes(tmpl) {
+				if !strings.HasPrefix(iname, "/") {
+					newUnresolved[iname] = filepath.Join(pwd, iname)
+				} else {
+					newUnresolved[iname] = iname
+				}
+			}
+		}
+		unresolved = newUnresolved
+	}
+
+	defines := map[string]string{"parent": parent}
+	var buf bytes.Buffer
+	if err := roottmpl.Execute(&buf, defines); err != nil {
+		log.Fatalf("Executing template failed: %v", err)
+	}
+
+	if err := os.WriteFile(outputFilename, buf.Bytes(), 0640); err != nil {
+		log.Fatalf("Writing output %q failed: %v", outputFilename, err)
+	}
+}