feat: support generic bin and intel hex firmware

internal/firmware/firmware.go

@@ -2,7 +2,6 @@ package firmware
 
 import (
 	"fmt"
-	"io"
 	"os"
 	"strings"
 )
@@ -35,9 +34,14 @@ func ExtractFileFormatFromCommand(cmd string) string {
 
 // ConvertFormats processes format conversions for embedded targets only
 func ConvertFormats(binFmt, fmtDetail string, envMap map[string]string) error {
+	var err error
 	// Convert to bin format first (needed for img)
 	if envMap["bin"] != "" {
-		err := makeFirmwareImage(envMap["out"], envMap["bin"], binFmt, fmtDetail)
+		if strings.HasPrefix(binFmt, "esp") {
+			err = makeFirmwareImage(envMap["out"], envMap["bin"], binFmt, fmtDetail)
+		} else {
+			err = objcopy(envMap["out"], envMap["bin"], "bin")
+		}
 		if err != nil {
 			return fmt.Errorf("failed to convert to bin format: %w", err)
 		}
@@ -45,7 +49,7 @@ func ConvertFormats(binFmt, fmtDetail string, envMap map[string]string) error {
 
 	// Convert to hex format
 	if envMap["hex"] != "" {
-		err := makeFirmwareImage(envMap["out"], envMap["hex"], binFmt, fmtDetail)
+		err := objcopy(envMap["out"], envMap["hex"], "hex")
 		if err != nil {
 			return fmt.Errorf("failed to convert to hex format: %w", err)
 		}
@@ -53,7 +57,7 @@ func ConvertFormats(binFmt, fmtDetail string, envMap map[string]string) error {
 
 	// Convert to img format
 	if envMap["img"] != "" {
-		err := makeFirmwareImage(envMap["out"], envMap["img"], binFmt+"-img", fmtDetail)
+		err = makeFirmwareImage(envMap["out"], envMap["img"], binFmt+"-img", fmtDetail)
 		if err != nil {
 			return fmt.Errorf("failed to convert to img format: %w", err)
 		}
@@ -77,38 +81,3 @@ func ConvertFormats(binFmt, fmtDetail string, envMap map[string]string) error {
 
 	return nil
 }
-
-// convertToHex converts binary file to hex format (each byte as two hex characters)
-func convertToHex(infile, outfile string) error {
-	srcFile, err := os.Open(infile)
-	if err != nil {
-		return err
-	}
-	defer srcFile.Close()
-
-	dstFile, err := os.Create(outfile)
-	if err != nil {
-		return err
-	}
-	defer dstFile.Close()
-
-	// Read input file and convert each byte to two hex characters
-	buf := make([]byte, 4096) // Read in chunks
-	for {
-		n, err := srcFile.Read(buf)
-		if n > 0 {
-			for i := 0; i < n; i++ {
-				if _, writeErr := fmt.Fprintf(dstFile, "%02x", buf[i]); writeErr != nil {
-					return writeErr
-				}
-			}
-		}
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			return err
-		}
-	}
-	return nil
-}

internal/firmware/objcopy.go

@@ -4,8 +4,12 @@ package firmware
 
 import (
 	"debug/elf"
+	"fmt"
 	"io"
+	"os"
 	"sort"
+
+	"github.com/marcinbor85/gohex"
 )
 
 // maxPadBytes is the maximum allowed bytes to be padded in a rom extraction
@@ -103,3 +107,41 @@ func extractROM(path string) (uint64, []byte, error) {
 		return progs[0].Paddr, rom, nil
 	}
 }
+
+// From tinygo/builder/builder/objcopy.go objcopy
+// objcopy converts an ELF file to a different (simpler) output file format:
+// .bin or .hex. It extracts only the .text section.
+func objcopy(infile, outfile, binaryFormat string) error {
+	f, err := os.OpenFile(outfile, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	// Read the .text segment.
+	addr, data, err := extractROM(infile)
+	if err != nil {
+		return err
+	}
+
+	// Write to the file, in the correct format.
+	switch binaryFormat {
+	case "hex":
+		fmt.Fprintf(os.Stderr, "Converting firmware format: %s -> %s (intel hex format: %s)\n", infile, outfile, binaryFormat)
+		// Intel hex file, includes the firmware start address.
+		mem := gohex.NewMemory()
+		err := mem.AddBinary(uint32(addr), data)
+		if err != nil {
+			return objcopyError{"failed to create .hex file", err}
+		}
+		return mem.DumpIntelHex(f, 16)
+	case "bin":
+		fmt.Fprintf(os.Stderr, "Converting firmware format: %s -> %s (format: %s)\n", infile, outfile, binaryFormat)
+		// The start address is not stored in raw firmware files (therefore you
+		// should use .hex files in most cases).
+		_, err := f.Write(data)
+		return err
+	default:
+		panic("unreachable")
+	}
+}