add dump command to picobin

blocks.go

@@ -20,73 +20,6 @@ var (
 	endMarker   = binary.LittleEndian.AppendUint32(nil, BlockMarkerEnd)
 )
 
-type Item struct {
-	Head uint8 // [0:1]:size_flag(0 means 1 byte size, 1 means 2 byte size) [1:7]: item type.
-	// Contains size and special data.
-	// [0:8]: s0%256
-	// [8:16]: s0/256 if size_flag==1, or is type specific data for blocks that are never >256 words.
-	SizeAndSpecial uint16
-	TypeData       uint8  // Type specific data.
-	Data           []byte // Item data.
-}
-
-// HeaderBytes returns the first 4 bytes of the item header as a static array.
-func (it Item) HeaderBytes() [4]byte {
-	return [4]byte{it.Head, byte(it.SizeAndSpecial), byte(it.SizeAndSpecial >> 8), it.TypeData}
-}
-
-type ItemType uint8
-
-// ItemType definitions.
-const (
-	ItemTypeVectorTable        ItemType = 0x03 // vector table
-	ItemTypeRollingWindowDelta ItemType = 0x05 // rolling window delta
-	ItemTypeRollingLoadMap     ItemType = 0x06 // load map
-	ItemTypeSignature          ItemType = 0x09 // signature
-	ItemTypePartitionTable     ItemType = 0x0A // partition table
-	ItemTypeSalt               ItemType = 0x0C // salt
-
-	ItemTypeNextBlockOffset ItemType = 0x41 // next block offset
-	ItemTypeImageDef        ItemType = 0x42 // image def
-	ItemTypeEntryPoint      ItemType = 0x44 // entry point
-	ItemTypeHashDef         ItemType = 0x47 // hash def
-	ItemTypeVersion         ItemType = 0x48 // version
-	ItemTypeHashValue       ItemType = 0x4b // hash value
-)
-
-// ItemType definitions for 2 byte items.
-const (
-	ItemTypeIgnored ItemType = 0x7e // ignored
-	ItemTypeLast    ItemType = 0x7f // last
-)
-
-func (it Item) sizeflag() bool { return it.Head&1 != 0 }
-
-// Size returns the size in bytes of the item.
-func (it Item) Size() int {
-	return it.SizeWords() * 4
-}
-
-// SizeWords returns the size in words (4 bytes each) of the item.
-func (it Item) SizeWords() int {
-	if it.sizeflag() {
-		return int(it.SizeAndSpecial)
-	}
-	return int(it.SizeAndSpecial & 0xff)
-}
-
-func (it Item) ItemType() ItemType { return ItemType(it.Head & 0x7f) }
-
-func (it Item) String() string {
-	switch it.ItemType() {
-	case ItemTypeImageDef:
-		return ImageDef{Item: it}.String()
-	case ItemTypeRollingLoadMap:
-		return LoadMap{Item: it}.String()
-	}
-	return fmt.Sprintf("Item(%s, size=%d)", it.ItemType(), it.Size())
-}
-
 type Block struct {
 	// Items is a list of items not including the ItemTypeLast item.
 	Items []Item

cmd/picobin/picobin.go

@@ -2,12 +2,15 @@ package main
 
 import (
 	"debug/elf"
+	"encoding/hex"
 	"errors"
 	"flag"
 	"fmt"
 	"log"
+	"os"
 
 	"github.com/github.com/soypat/picobin"
+	"golang.org/x/exp/constraints"
 )
 
 const (
@@ -16,6 +19,10 @@ const (
 	MB
 )
 
+type Flags struct {
+	block int
+}
+
 func main() {
 	err := run()
 	if err != nil {
@@ -24,52 +31,126 @@ func main() {
 }
 
 func run() error {
+	var flags Flags
+	flag.Usage = func() {
+		output := flag.CommandLine.Output()
+		fmt.Fprintf(output, "Usage of %s:\n", os.Args[0])
+		fmt.Fprintf(output, "\tavailable commands: [info, dump]\n")
+		fmt.Fprintf(output, "Example:\n\tpicobin info <ELF-filename>\n")
+		flag.PrintDefaults()
+	}
+	flag.IntVar(&flags.block, "block", -1, "Specify a single block to analyze")
 	flag.Parse()
-	filename := flag.Arg(0)
-	if filename == "" {
+	command := flag.Arg(0)
+	source := flag.Arg(1)
+	// First check command argument.
+	if command == "" {
+		flag.Usage()
+		return errors.New("missing command argument")
+	}
+	var cmd func(*elf.File, Flags) error
+	switch command {
+	case "info":
+		cmd = info
+	case "dump":
+		cmd = dump
+	default:
+		flag.Usage()
+		return errors.New("uknown command: " + command)
+	}
+
+	// Next check filename.
+	if source == "" {
+		flag.Usage()
 		return errors.New("missing filename argument")
 	}
-	file, err := elf.Open(filename)
+	file, err := elf.Open(source)
 	if err != nil {
 		return err
 	}
 	defer file.Close()
 
+	// Finally run command.
+	return cmd(file, flags)
+}
+
+func info(f *elf.File, flags Flags) error {
+	blocks, start, err := getBlocks(f)
+	if err != nil {
+		return err
+	}
+	addr := start
+	for i, block := range blocks {
+		if flags.block >= 0 && i != flags.block {
+			addr += int64(block.Link)
+			continue
+		}
+		fmt.Printf("BLOCK%d @ Addr=%#x Size=%d Items=%d\n", i, addr, block.Size(), len(block.Items))
+		for _, item := range block.Items {
+			fmt.Printf("\t%s\n", item.String())
+		}
+		addr += int64(block.Link)
+	}
+	return nil
+}
+
+func dump(f *elf.File, flags Flags) error {
+	blocks, start, err := getBlocks(f)
+	if err != nil {
+		return err
+	}
+	addr := start
+	for i, block := range blocks {
+		if flags.block >= 0 && i != flags.block || len(block.Items) >= 1 && block.Items[0].ItemType() == picobin.ItemTypeIgnored {
+			addr += int64(block.Link)
+			continue
+		}
+		blockSize := block.Size()
+		dataSize := block.Link - blockSize
+		if dataSize < 0 {
+			break // Last block.
+		}
+		data := make([]byte, dataSize)
+		n, err := readAddr(f, addr+int64(blockSize), data)
+		if err != nil {
+			return err
+		} else if n == 0 {
+			return errors.New("unable to extract data after block")
+		}
+		fmt.Printf("BLOCK%d @ Addr=%#x dump:\n%s", i, addr, hex.Dump(data))
+		addr += int64(block.Link)
+	}
+	return nil
+}
+
+func getBlocks(f *elf.File) ([]picobin.Block, int64, error) {
 	var flash [2 * MB]byte
 	const flashAddr = 0x10000000
-	flashEnd, err := readAddr(file, flashAddr, flash[:])
+	flashEnd, err := readAddr(f, flashAddr, flash[:])
 	if err != nil {
-		return err
+		return nil, 0, err
 	}
 	start0, _, err := picobin.NextBlockIdx(flash[:flashEnd])
 	if err != nil {
-		return err
+		return nil, 0, err
 	}
 	var blocks []picobin.Block
-	var blkaddr []int
 	start := start0
+	startAbs := int64(start) + flashAddr
 	for {
 		absAddr := start + flashAddr
 		block, _, err := picobin.DecodeBlock(flash[start:flashEnd])
 		if err != nil {
-			return fmt.Errorf("decoding block at Addr=%#x: %w", absAddr, err)
+			return blocks, startAbs, fmt.Errorf("decoding block at Addr=%#x: %w", absAddr, err)
 		}
 		blocks = append(blocks, block)
-		blkaddr = append(blkaddr, absAddr)
 		nextStart := start + block.Link
 		if nextStart == start0 {
 			break // Found last block.
 		}
 		start = nextStart
 	}
-	for i, block := range blocks {
-		addr := blkaddr[i]
-		fmt.Printf("BLOCK%d @ Addr=%#x Size=%d Items=%d\n", i, addr, block.Size(), len(block.Items))
-		for _, item := range block.Items {
-			fmt.Printf("\t%s\n", item.String())
-		}
-	}
-	return nil
+	return blocks, startAbs, nil
 }
 
 func readAddr(f *elf.File, addr int64, b []byte) (int, error) {
@@ -78,29 +159,42 @@ func readAddr(f *elf.File, addr int64, b []byte) (int, error) {
 	maxReadIdx := 0
 	for _, section := range f.Sections {
 		saddr := int64(section.Addr)
-		if saddr >= addr && saddr < end {
+		send := saddr + int64(section.Size)
+		if aliases(addr, end, saddr, send) {
 			data, err := section.Data()
 			if err != nil {
 				return 0, err
 			}
-			off := int(saddr - addr)
-			n := copy(b[off:], data)
-			maxReadIdx = max(maxReadIdx, n+off)
+			sectOff := max(0, int(addr-saddr))
+			bOff := max(0, int(saddr-addr))
+			n := copy(b[bOff:], data[sectOff:])
+			maxReadIdx = max(maxReadIdx, n+bOff)
 		}
 	}
 	return maxReadIdx, nil
 }
 
+func aliases(start0, end0, start1, end1 int64) bool {
+	return start0 < end1 && end0 > start1
+}
+
 func clear[E any](a []E) {
 	var z E
 	for i := range a {
 		a[i] = z
 	}
 }
 
-func max(a, b int) int {
+func max[T constraints.Integer](a, b T) T {
 	if a > b {
 		return a
 	}
 	return b
 }
+
+func min[T constraints.Integer](a, b T) T {
+	if a < b {
+		return a
+	}
+	return b
+}

cmd/picobin/picobin_test.go

@@ -0,0 +1,14 @@
+package main
+
+import (
+	"debug/elf"
+	"testing"
+)
+
+func TestDump(t *testing.T) {
+	fp, err := elf.Open("../../blink.elf")
+	if err != nil {
+		t.Fatal(err)
+	}
+	dump(fp, Flags{block: 0})
+}

go.mod

@@ -1,3 +1,7 @@
 module github.com/github.com/soypat/picobin
 
-go 1.18
+go 1.22.0
+
+toolchain go1.23.0
+
+require golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 // indirect

go.sum

@@ -0,0 +1,2 @@
+golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 h1:e66Fs6Z+fZTbFBAxKfP3PALWBtpfqks2bwGcexMxgtk=
+golang.org/x/exp v0.0.0-20240909161429-701f63a606c0/go.mod h1:2TbTHSBQa924w8M6Xs1QcRcFwyucIwBGpK1p2f1YFFY=