gotosocial/vendor/github.com/dsoprea/go-exif/v3/ifd_builder.go
2022-01-23 14:41:31 +01:00

1199 lines
29 KiB
Go

package exif
// NOTES:
//
// The thumbnail offset and length tags shouldn't be set directly. Use the
// (*IfdBuilder).SetThumbnail() method instead.
import (
"errors"
"fmt"
"strings"
"encoding/binary"
"github.com/dsoprea/go-logging"
"github.com/dsoprea/go-exif/v3/common"
"github.com/dsoprea/go-exif/v3/undefined"
)
var (
ifdBuilderLogger = log.NewLogger("exif.ifd_builder")
)
var (
ErrTagEntryNotFound = errors.New("tag entry not found")
ErrChildIbNotFound = errors.New("child IB not found")
)
type IfdBuilderTagValue struct {
valueBytes []byte
ib *IfdBuilder
}
func (ibtv IfdBuilderTagValue) String() string {
if ibtv.IsBytes() == true {
var valuePhrase string
if len(ibtv.valueBytes) <= 8 {
valuePhrase = fmt.Sprintf("%v", ibtv.valueBytes)
} else {
valuePhrase = fmt.Sprintf("%v...", ibtv.valueBytes[:8])
}
return fmt.Sprintf("IfdBuilderTagValue<BYTES=%v LEN=(%d)>", valuePhrase, len(ibtv.valueBytes))
} else if ibtv.IsIb() == true {
return fmt.Sprintf("IfdBuilderTagValue<IB=%s>", ibtv.ib)
} else {
log.Panicf("IBTV state undefined")
return ""
}
}
func NewIfdBuilderTagValueFromBytes(valueBytes []byte) *IfdBuilderTagValue {
return &IfdBuilderTagValue{
valueBytes: valueBytes,
}
}
func NewIfdBuilderTagValueFromIfdBuilder(ib *IfdBuilder) *IfdBuilderTagValue {
return &IfdBuilderTagValue{
ib: ib,
}
}
// IsBytes returns true if the bytes are populated. This is always the case
// when we're loaded from a tag in an existing IFD.
func (ibtv IfdBuilderTagValue) IsBytes() bool {
return ibtv.valueBytes != nil
}
func (ibtv IfdBuilderTagValue) Bytes() []byte {
if ibtv.IsBytes() == false {
log.Panicf("this tag is not a byte-slice value")
} else if ibtv.IsIb() == true {
log.Panicf("this tag is an IFD-builder value not a byte-slice")
}
return ibtv.valueBytes
}
func (ibtv IfdBuilderTagValue) IsIb() bool {
return ibtv.ib != nil
}
func (ibtv IfdBuilderTagValue) Ib() *IfdBuilder {
if ibtv.IsIb() == false {
log.Panicf("this tag is not an IFD-builder value")
} else if ibtv.IsBytes() == true {
log.Panicf("this tag is a byte-slice, not a IFD-builder")
}
return ibtv.ib
}
type BuilderTag struct {
// ifdPath is the path of the IFD that hosts this tag.
ifdPath string
tagId uint16
typeId exifcommon.TagTypePrimitive
// value is either a value that can be encoded, an IfdBuilder instance (for
// child IFDs), or an IfdTagEntry instance representing an existing,
// previously-stored tag.
value *IfdBuilderTagValue
// byteOrder is the byte order. It's chiefly/originally here to support
// printing the value.
byteOrder binary.ByteOrder
}
func NewBuilderTag(ifdPath string, tagId uint16, typeId exifcommon.TagTypePrimitive, value *IfdBuilderTagValue, byteOrder binary.ByteOrder) *BuilderTag {
return &BuilderTag{
ifdPath: ifdPath,
tagId: tagId,
typeId: typeId,
value: value,
byteOrder: byteOrder,
}
}
func NewChildIfdBuilderTag(ifdPath string, tagId uint16, value *IfdBuilderTagValue) *BuilderTag {
return &BuilderTag{
ifdPath: ifdPath,
tagId: tagId,
typeId: exifcommon.TypeLong,
value: value,
}
}
func (bt *BuilderTag) Value() (value *IfdBuilderTagValue) {
return bt.value
}
func (bt *BuilderTag) String() string {
var valueString string
if bt.value.IsBytes() == true {
var err error
valueString, err = exifcommon.FormatFromBytes(bt.value.Bytes(), bt.typeId, false, bt.byteOrder)
log.PanicIf(err)
} else {
valueString = fmt.Sprintf("%v", bt.value)
}
return fmt.Sprintf("BuilderTag<IFD-PATH=[%s] TAG-ID=(0x%04x) TAG-TYPE=[%s] VALUE=[%s]>", bt.ifdPath, bt.tagId, bt.typeId.String(), valueString)
}
func (bt *BuilderTag) SetValue(byteOrder binary.ByteOrder, value interface{}) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
// TODO(dustin): !! Add test.
var ed exifcommon.EncodedData
if bt.typeId == exifcommon.TypeUndefined {
encodeable := value.(exifundefined.EncodeableValue)
encoded, unitCount, err := exifundefined.Encode(encodeable, byteOrder)
log.PanicIf(err)
ed = exifcommon.EncodedData{
Type: exifcommon.TypeUndefined,
Encoded: encoded,
UnitCount: unitCount,
}
} else {
ve := exifcommon.NewValueEncoder(byteOrder)
var err error
ed, err = ve.Encode(value)
log.PanicIf(err)
}
bt.value = NewIfdBuilderTagValueFromBytes(ed.Encoded)
return nil
}
// NewStandardBuilderTag constructs a `BuilderTag` instance. The type is looked
// up. `ii` is the type of IFD that owns this tag.
func NewStandardBuilderTag(ifdPath string, it *IndexedTag, byteOrder binary.ByteOrder, value interface{}) *BuilderTag {
// If there is more than one supported type, we'll go with the larger to
// encode with. It'll use the same amount of fixed-space, and we'll
// eliminate unnecessary overflows/issues.
tagType := it.GetEncodingType(value)
var rawBytes []byte
if it.DoesSupportType(exifcommon.TypeUndefined) == true {
encodeable := value.(exifundefined.EncodeableValue)
var err error
rawBytes, _, err = exifundefined.Encode(encodeable, byteOrder)
log.PanicIf(err)
} else {
ve := exifcommon.NewValueEncoder(byteOrder)
ed, err := ve.Encode(value)
log.PanicIf(err)
rawBytes = ed.Encoded
}
tagValue := NewIfdBuilderTagValueFromBytes(rawBytes)
return NewBuilderTag(
ifdPath,
it.Id,
tagType,
tagValue,
byteOrder)
}
type IfdBuilder struct {
ifdIdentity *exifcommon.IfdIdentity
byteOrder binary.ByteOrder
// Includes both normal tags and IFD tags (which point to child IFDs).
// TODO(dustin): Keep a separate list of children like with `Ifd`.
// TODO(dustin): Either rename this or `Entries` in `Ifd` to be the same thing.
tags []*BuilderTag
// existingOffset will be the offset that this IFD is currently found at if
// it represents an IFD that has previously been stored (or 0 if not).
existingOffset uint32
// nextIb represents the next link if we're chaining to another.
nextIb *IfdBuilder
// thumbnailData is populated with thumbnail data if there was thumbnail
// data. Otherwise, it's nil.
thumbnailData []byte
ifdMapping *exifcommon.IfdMapping
tagIndex *TagIndex
}
func NewIfdBuilder(ifdMapping *exifcommon.IfdMapping, tagIndex *TagIndex, ii *exifcommon.IfdIdentity, byteOrder binary.ByteOrder) (ib *IfdBuilder) {
ib = &IfdBuilder{
ifdIdentity: ii,
byteOrder: byteOrder,
tags: make([]*BuilderTag, 0),
ifdMapping: ifdMapping,
tagIndex: tagIndex,
}
return ib
}
// NewIfdBuilderWithExistingIfd creates a new IB using the same header type
// information as the given IFD.
func NewIfdBuilderWithExistingIfd(ifd *Ifd) (ib *IfdBuilder) {
ib = &IfdBuilder{
ifdIdentity: ifd.IfdIdentity(),
byteOrder: ifd.ByteOrder(),
existingOffset: ifd.Offset(),
ifdMapping: ifd.ifdMapping,
tagIndex: ifd.tagIndex,
}
return ib
}
// NewIfdBuilderFromExistingChain creates a chain of IB instances from an
// IFD chain generated from real data.
func NewIfdBuilderFromExistingChain(rootIfd *Ifd) (firstIb *IfdBuilder) {
var lastIb *IfdBuilder
i := 0
for thisExistingIfd := rootIfd; thisExistingIfd != nil; thisExistingIfd = thisExistingIfd.nextIfd {
newIb := NewIfdBuilder(
rootIfd.ifdMapping,
rootIfd.tagIndex,
rootIfd.ifdIdentity,
thisExistingIfd.ByteOrder())
if firstIb == nil {
firstIb = newIb
} else {
lastIb.SetNextIb(newIb)
}
err := newIb.AddTagsFromExisting(thisExistingIfd, nil, nil)
log.PanicIf(err)
lastIb = newIb
i++
}
return firstIb
}
func (ib *IfdBuilder) IfdIdentity() *exifcommon.IfdIdentity {
return ib.ifdIdentity
}
func (ib *IfdBuilder) NextIb() (nextIb *IfdBuilder, err error) {
return ib.nextIb, nil
}
func (ib *IfdBuilder) ChildWithTagId(childIfdTagId uint16) (childIb *IfdBuilder, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
for _, bt := range ib.tags {
if bt.value.IsIb() == false {
continue
}
childIbThis := bt.value.Ib()
if childIbThis.IfdIdentity().TagId() == childIfdTagId {
return childIbThis, nil
}
}
log.Panic(ErrChildIbNotFound)
// Never reached.
return nil, nil
}
func getOrCreateIbFromRootIbInner(rootIb *IfdBuilder, parentIb *IfdBuilder, currentLineage []exifcommon.IfdTagIdAndIndex) (ib *IfdBuilder, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
// TODO(dustin): !! Add test.
thisIb := rootIb
// Since we're calling ourselves recursively with incrementally different
// paths, the FQ IFD-path of the parent that called us needs to be passed
// in, in order for us to know it.
var parentLineage []exifcommon.IfdTagIdAndIndex
if parentIb != nil {
var err error
parentLineage, err = thisIb.ifdMapping.ResolvePath(parentIb.IfdIdentity().String())
log.PanicIf(err)
}
// Process the current path part.
currentItIi := currentLineage[0]
// Make sure the leftmost part of the FQ IFD-path agrees with the IB we
// were given.
expectedFqRootIfdPath := ""
if parentLineage != nil {
expectedLineage := append(parentLineage, currentItIi)
expectedFqRootIfdPath = thisIb.ifdMapping.PathPhraseFromLineage(expectedLineage)
} else {
expectedFqRootIfdPath = thisIb.ifdMapping.PathPhraseFromLineage(currentLineage[:1])
}
if expectedFqRootIfdPath != thisIb.IfdIdentity().String() {
log.Panicf("the FQ IFD-path [%s] we were given does not match the builder's FQ IFD-path [%s]", expectedFqRootIfdPath, thisIb.IfdIdentity().String())
}
// If we actually wanted a sibling (currentItIi.Index > 0) then seek to it,
// appending new siblings, as required, until we get there.
for i := 0; i < currentItIi.Index; i++ {
if thisIb.nextIb == nil {
// Generate an FQ IFD-path for the sibling. It'll use the same
// non-FQ IFD-path as the current IB.
iiSibling := thisIb.IfdIdentity().NewSibling(i + 1)
thisIb.nextIb = NewIfdBuilder(thisIb.ifdMapping, thisIb.tagIndex, iiSibling, thisIb.byteOrder)
}
thisIb = thisIb.nextIb
}
// There is no child IFD to process. We're done.
if len(currentLineage) == 1 {
return thisIb, nil
}
// Establish the next child to be processed.
childItii := currentLineage[1]
var foundChild *IfdBuilder
for _, bt := range thisIb.tags {
if bt.value.IsIb() == false {
continue
}
childIb := bt.value.Ib()
if childIb.IfdIdentity().TagId() == childItii.TagId {
foundChild = childIb
break
}
}
// If we didn't find the child, add it.
if foundChild == nil {
currentIfdTag := thisIb.IfdIdentity().IfdTag()
childIfdTag :=
exifcommon.NewIfdTag(
&currentIfdTag,
childItii.TagId,
childItii.Name)
iiChild := thisIb.IfdIdentity().NewChild(childIfdTag, 0)
foundChild =
NewIfdBuilder(
thisIb.ifdMapping,
thisIb.tagIndex,
iiChild,
thisIb.byteOrder)
err = thisIb.AddChildIb(foundChild)
log.PanicIf(err)
}
finalIb, err := getOrCreateIbFromRootIbInner(foundChild, thisIb, currentLineage[1:])
log.PanicIf(err)
return finalIb, nil
}
// GetOrCreateIbFromRootIb returns an IB representing the requested IFD, even if
// an IB doesn't already exist for it. This function may call itself
// recursively.
func GetOrCreateIbFromRootIb(rootIb *IfdBuilder, fqIfdPath string) (ib *IfdBuilder, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
// lineage is a necessity of our recursion process. It doesn't include any
// parent IFDs on its left-side; it starts with the current IB only.
lineage, err := rootIb.ifdMapping.ResolvePath(fqIfdPath)
log.PanicIf(err)
ib, err = getOrCreateIbFromRootIbInner(rootIb, nil, lineage)
log.PanicIf(err)
return ib, nil
}
func (ib *IfdBuilder) String() string {
nextIfdPhrase := ""
if ib.nextIb != nil {
// TODO(dustin): We were setting this to ii.String(), but we were getting hex-data when printing this after building from an existing chain.
nextIfdPhrase = ib.nextIb.IfdIdentity().UnindexedString()
}
return fmt.Sprintf("IfdBuilder<PATH=[%s] TAG-ID=(0x%04x) COUNT=(%d) OFF=(0x%04x) NEXT-IFD-PATH=[%s]>", ib.IfdIdentity().UnindexedString(), ib.IfdIdentity().TagId(), len(ib.tags), ib.existingOffset, nextIfdPhrase)
}
func (ib *IfdBuilder) Tags() (tags []*BuilderTag) {
return ib.tags
}
// SetThumbnail sets thumbnail data.
//
// NOTES:
//
// - We don't manage any facet of the thumbnail data. This is the
// responsibility of the user/developer.
// - This method will fail unless the thumbnail is set on a the root IFD.
// However, in order to be valid, it must be set on the second one, linked to
// by the first, as per the EXIF/TIFF specification.
// - We set the offset to (0) now but will allocate the data and properly assign
// the offset when the IB is encoded (later).
func (ib *IfdBuilder) SetThumbnail(data []byte) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if ib.IfdIdentity().UnindexedString() != exifcommon.IfdStandardIfdIdentity.UnindexedString() {
log.Panicf("thumbnails can only go into a root Ifd (and only the second one)")
}
// TODO(dustin): !! Add a test for this function.
if data == nil || len(data) == 0 {
log.Panic("thumbnail is empty")
}
ib.thumbnailData = data
ibtvfb := NewIfdBuilderTagValueFromBytes(ib.thumbnailData)
offsetBt :=
NewBuilderTag(
ib.IfdIdentity().UnindexedString(),
ThumbnailOffsetTagId,
exifcommon.TypeLong,
ibtvfb,
ib.byteOrder)
err = ib.Set(offsetBt)
log.PanicIf(err)
thumbnailSizeIt, err := ib.tagIndex.Get(ib.IfdIdentity(), ThumbnailSizeTagId)
log.PanicIf(err)
sizeBt := NewStandardBuilderTag(ib.IfdIdentity().UnindexedString(), thumbnailSizeIt, ib.byteOrder, []uint32{uint32(len(ib.thumbnailData))})
err = ib.Set(sizeBt)
log.PanicIf(err)
return nil
}
func (ib *IfdBuilder) Thumbnail() []byte {
return ib.thumbnailData
}
func (ib *IfdBuilder) printTagTree(levels int) {
indent := strings.Repeat(" ", levels*2)
i := 0
for currentIb := ib; currentIb != nil; currentIb = currentIb.nextIb {
prefix := " "
if i > 0 {
prefix = ">"
}
if levels == 0 {
fmt.Printf("%s%sIFD: %s INDEX=(%d)\n", indent, prefix, currentIb, i)
} else {
fmt.Printf("%s%sChild IFD: %s\n", indent, prefix, currentIb)
}
if len(currentIb.tags) > 0 {
fmt.Printf("\n")
for i, tag := range currentIb.tags {
isChildIb := false
_, err := ib.ifdMapping.GetChild(currentIb.IfdIdentity().UnindexedString(), tag.tagId)
if err == nil {
isChildIb = true
} else if log.Is(err, exifcommon.ErrChildIfdNotMapped) == false {
log.Panic(err)
}
tagName := ""
// If a normal tag (not a child IFD) get the name.
if isChildIb == true {
tagName = "<Child IFD>"
} else {
it, err := ib.tagIndex.Get(ib.ifdIdentity, tag.tagId)
if log.Is(err, ErrTagNotFound) == true {
tagName = "<UNKNOWN>"
} else if err != nil {
log.Panic(err)
} else {
tagName = it.Name
}
}
value := tag.Value()
if value.IsIb() == true {
fmt.Printf("%s (%d): [%s] %s\n", indent, i, tagName, value.Ib())
} else {
fmt.Printf("%s (%d): [%s] %s\n", indent, i, tagName, tag)
}
if isChildIb == true {
if tag.value.IsIb() == false {
log.Panicf("tag-ID (0x%04x) is an IFD but the tag value is not an IB instance: %v", tag.tagId, tag)
}
fmt.Printf("\n")
childIb := tag.value.Ib()
childIb.printTagTree(levels + 1)
}
}
fmt.Printf("\n")
}
i++
}
}
func (ib *IfdBuilder) PrintTagTree() {
ib.printTagTree(0)
}
func (ib *IfdBuilder) printIfdTree(levels int) {
indent := strings.Repeat(" ", levels*2)
i := 0
for currentIb := ib; currentIb != nil; currentIb = currentIb.nextIb {
prefix := " "
if i > 0 {
prefix = ">"
}
fmt.Printf("%s%s%s\n", indent, prefix, currentIb)
if len(currentIb.tags) > 0 {
for _, tag := range currentIb.tags {
isChildIb := false
_, err := ib.ifdMapping.GetChild(currentIb.IfdIdentity().UnindexedString(), tag.tagId)
if err == nil {
isChildIb = true
} else if log.Is(err, exifcommon.ErrChildIfdNotMapped) == false {
log.Panic(err)
}
if isChildIb == true {
if tag.value.IsIb() == false {
log.Panicf("tag-ID (0x%04x) is an IFD but the tag value is not an IB instance: %v", tag.tagId, tag)
}
childIb := tag.value.Ib()
childIb.printIfdTree(levels + 1)
}
}
}
i++
}
}
func (ib *IfdBuilder) PrintIfdTree() {
ib.printIfdTree(0)
}
func (ib *IfdBuilder) dumpToStrings(thisIb *IfdBuilder, prefix string, tagId uint16, lines []string) (linesOutput []string) {
if lines == nil {
linesOutput = make([]string, 0)
} else {
linesOutput = lines
}
siblingIfdIndex := 0
for ; thisIb != nil; thisIb = thisIb.nextIb {
line := fmt.Sprintf("IFD<PARENTS=[%s] FQ-IFD-PATH=[%s] IFD-INDEX=(%d) IFD-TAG-ID=(0x%04x) TAG=[0x%04x]>", prefix, thisIb.IfdIdentity().String(), siblingIfdIndex, thisIb.IfdIdentity().TagId(), tagId)
linesOutput = append(linesOutput, line)
for i, tag := range thisIb.tags {
var childIb *IfdBuilder
childIfdName := ""
if tag.value.IsIb() == true {
childIb = tag.value.Ib()
childIfdName = childIb.IfdIdentity().UnindexedString()
}
line := fmt.Sprintf("TAG<PARENTS=[%s] FQ-IFD-PATH=[%s] IFD-TAG-ID=(0x%04x) CHILD-IFD=[%s] TAG-INDEX=(%d) TAG=[0x%04x]>", prefix, thisIb.IfdIdentity().String(), thisIb.IfdIdentity().TagId(), childIfdName, i, tag.tagId)
linesOutput = append(linesOutput, line)
if childIb == nil {
continue
}
childPrefix := ""
if prefix == "" {
childPrefix = fmt.Sprintf("%s", thisIb.IfdIdentity().UnindexedString())
} else {
childPrefix = fmt.Sprintf("%s->%s", prefix, thisIb.IfdIdentity().UnindexedString())
}
linesOutput = thisIb.dumpToStrings(childIb, childPrefix, tag.tagId, linesOutput)
}
siblingIfdIndex++
}
return linesOutput
}
func (ib *IfdBuilder) DumpToStrings() (lines []string) {
return ib.dumpToStrings(ib, "", 0, lines)
}
func (ib *IfdBuilder) SetNextIb(nextIb *IfdBuilder) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
ib.nextIb = nextIb
return nil
}
func (ib *IfdBuilder) DeleteN(tagId uint16, n int) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if n < 1 {
log.Panicf("N must be at least 1: (%d)", n)
}
for n > 0 {
j := -1
for i, bt := range ib.tags {
if bt.tagId == tagId {
j = i
break
}
}
if j == -1 {
log.Panic(ErrTagEntryNotFound)
}
ib.tags = append(ib.tags[:j], ib.tags[j+1:]...)
n--
}
return nil
}
func (ib *IfdBuilder) DeleteFirst(tagId uint16) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
err = ib.DeleteN(tagId, 1)
log.PanicIf(err)
return nil
}
func (ib *IfdBuilder) DeleteAll(tagId uint16) (n int, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
for {
err = ib.DeleteN(tagId, 1)
if log.Is(err, ErrTagEntryNotFound) == true {
break
} else if err != nil {
log.Panic(err)
}
n++
}
return n, nil
}
func (ib *IfdBuilder) ReplaceAt(position int, bt *BuilderTag) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if position < 0 {
log.Panicf("replacement position must be 0 or greater")
} else if position >= len(ib.tags) {
log.Panicf("replacement position does not exist")
}
ib.tags[position] = bt
return nil
}
func (ib *IfdBuilder) Replace(tagId uint16, bt *BuilderTag) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
position, err := ib.Find(tagId)
log.PanicIf(err)
ib.tags[position] = bt
return nil
}
// Set will add a new entry or update an existing entry.
func (ib *IfdBuilder) Set(bt *BuilderTag) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
position, err := ib.Find(bt.tagId)
if err == nil {
ib.tags[position] = bt
} else if log.Is(err, ErrTagEntryNotFound) == true {
err = ib.add(bt)
log.PanicIf(err)
} else {
log.Panic(err)
}
return nil
}
func (ib *IfdBuilder) FindN(tagId uint16, maxFound int) (found []int, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
found = make([]int, 0)
for i, bt := range ib.tags {
if bt.tagId == tagId {
found = append(found, i)
if maxFound == 0 || len(found) >= maxFound {
break
}
}
}
return found, nil
}
func (ib *IfdBuilder) Find(tagId uint16) (position int, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
found, err := ib.FindN(tagId, 1)
log.PanicIf(err)
if len(found) == 0 {
log.Panic(ErrTagEntryNotFound)
}
return found[0], nil
}
func (ib *IfdBuilder) FindTag(tagId uint16) (bt *BuilderTag, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
found, err := ib.FindN(tagId, 1)
log.PanicIf(err)
if len(found) == 0 {
log.Panic(ErrTagEntryNotFound)
}
position := found[0]
return ib.tags[position], nil
}
func (ib *IfdBuilder) FindTagWithName(tagName string) (bt *BuilderTag, err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
it, err := ib.tagIndex.GetWithName(ib.IfdIdentity(), tagName)
log.PanicIf(err)
found, err := ib.FindN(it.Id, 1)
log.PanicIf(err)
if len(found) == 0 {
log.Panic(ErrTagEntryNotFound)
}
position := found[0]
return ib.tags[position], nil
}
func (ib *IfdBuilder) add(bt *BuilderTag) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if bt.ifdPath == "" {
log.Panicf("BuilderTag ifdPath is not set: %s", bt)
} else if bt.typeId == 0x0 {
log.Panicf("BuilderTag type-ID is not set: %s", bt)
} else if bt.value == nil {
log.Panicf("BuilderTag value is not set: %s", bt)
}
ib.tags = append(ib.tags, bt)
return nil
}
func (ib *IfdBuilder) Add(bt *BuilderTag) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if bt.value.IsIb() == true {
log.Panicf("child IfdBuilders must be added via AddChildIb() or AddTagsFromExisting(), not Add()")
}
err = ib.add(bt)
log.PanicIf(err)
return nil
}
// AddChildIb adds a tag that branches to a new IFD.
func (ib *IfdBuilder) AddChildIb(childIb *IfdBuilder) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
if childIb.IfdIdentity().TagId() == 0 {
log.Panicf("IFD can not be used as a child IFD (not associated with a tag-ID): %v", childIb)
} else if childIb.byteOrder != ib.byteOrder {
log.Panicf("Child IFD does not have the same byte-order: [%s] != [%s]", childIb.byteOrder, ib.byteOrder)
}
// Since no standard IFDs supports occur`ring more than once, check that a
// tag of this type has not been previously added. Note that we just search
// the current IFD and *not every* IFD.
for _, bt := range childIb.tags {
if bt.tagId == childIb.IfdIdentity().TagId() {
log.Panicf("child-IFD already added: %v", childIb.IfdIdentity().UnindexedString())
}
}
bt := ib.NewBuilderTagFromBuilder(childIb)
ib.tags = append(ib.tags, bt)
return nil
}
func (ib *IfdBuilder) NewBuilderTagFromBuilder(childIb *IfdBuilder) (bt *BuilderTag) {
defer func() {
if state := recover(); state != nil {
err := log.Wrap(state.(error))
log.Panic(err)
}
}()
value := NewIfdBuilderTagValueFromIfdBuilder(childIb)
bt = NewChildIfdBuilderTag(
ib.IfdIdentity().UnindexedString(),
childIb.IfdIdentity().TagId(),
value)
return bt
}
// AddTagsFromExisting does a verbatim copy of the entries in `ifd` to this
// builder. It excludes child IFDs. These must be added explicitly via
// `AddChildIb()`.
func (ib *IfdBuilder) AddTagsFromExisting(ifd *Ifd, includeTagIds []uint16, excludeTagIds []uint16) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
thumbnailData, err := ifd.Thumbnail()
if err == nil {
err = ib.SetThumbnail(thumbnailData)
log.PanicIf(err)
} else if log.Is(err, ErrNoThumbnail) == false {
log.Panic(err)
}
for i, ite := range ifd.Entries() {
if ite.IsThumbnailOffset() == true || ite.IsThumbnailSize() {
// These will be added on-the-fly when we encode.
continue
}
if excludeTagIds != nil && len(excludeTagIds) > 0 {
found := false
for _, excludedTagId := range excludeTagIds {
if excludedTagId == ite.TagId() {
found = true
}
}
if found == true {
continue
}
}
if includeTagIds != nil && len(includeTagIds) > 0 {
// Whether or not there was a list of excludes, if there is a list
// of includes than the current tag has to be in it.
found := false
for _, includedTagId := range includeTagIds {
if includedTagId == ite.TagId() {
found = true
break
}
}
if found == false {
continue
}
}
var bt *BuilderTag
if ite.ChildIfdPath() != "" {
// If we want to add an IFD tag, we'll have to build it first and
// *then* add it via a different method.
// Figure out which of the child-IFDs that are associated with
// this IFD represents this specific child IFD.
var childIfd *Ifd
for _, thisChildIfd := range ifd.Children() {
if thisChildIfd.ParentTagIndex() != i {
continue
} else if thisChildIfd.ifdIdentity.TagId() != 0xffff && thisChildIfd.ifdIdentity.TagId() != ite.TagId() {
log.Panicf("child-IFD tag is not correct: TAG-POSITION=(%d) ITE=%s CHILD-IFD=%s", thisChildIfd.ParentTagIndex(), ite, thisChildIfd)
}
childIfd = thisChildIfd
break
}
if childIfd == nil {
childTagIds := make([]string, len(ifd.Children()))
for j, childIfd := range ifd.Children() {
childTagIds[j] = fmt.Sprintf("0x%04x (parent tag-position %d)", childIfd.ifdIdentity.TagId(), childIfd.ParentTagIndex())
}
log.Panicf("could not find child IFD for child ITE: IFD-PATH=[%s] TAG-ID=(0x%04x) CURRENT-TAG-POSITION=(%d) CHILDREN=%v", ite.IfdPath(), ite.TagId(), i, childTagIds)
}
childIb := NewIfdBuilderFromExistingChain(childIfd)
bt = ib.NewBuilderTagFromBuilder(childIb)
} else {
// Non-IFD tag.
rawBytes, err := ite.GetRawBytes()
log.PanicIf(err)
value := NewIfdBuilderTagValueFromBytes(rawBytes)
bt = NewBuilderTag(
ifd.ifdIdentity.UnindexedString(),
ite.TagId(),
ite.TagType(),
value,
ib.byteOrder)
}
err := ib.add(bt)
log.PanicIf(err)
}
return nil
}
// AddStandard quickly and easily composes and adds the tag using the
// information already known about a tag. Only works with standard tags.
func (ib *IfdBuilder) AddStandard(tagId uint16, value interface{}) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
it, err := ib.tagIndex.Get(ib.IfdIdentity(), tagId)
log.PanicIf(err)
bt := NewStandardBuilderTag(ib.IfdIdentity().UnindexedString(), it, ib.byteOrder, value)
err = ib.add(bt)
log.PanicIf(err)
return nil
}
// AddStandardWithName quickly and easily composes and adds the tag using the
// information already known about a tag (using the name). Only works with
// standard tags.
func (ib *IfdBuilder) AddStandardWithName(tagName string, value interface{}) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
it, err := ib.tagIndex.GetWithName(ib.IfdIdentity(), tagName)
log.PanicIf(err)
bt := NewStandardBuilderTag(ib.IfdIdentity().UnindexedString(), it, ib.byteOrder, value)
err = ib.add(bt)
log.PanicIf(err)
return nil
}
// SetStandard quickly and easily composes and adds or replaces the tag using
// the information already known about a tag. Only works with standard tags.
func (ib *IfdBuilder) SetStandard(tagId uint16, value interface{}) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
// TODO(dustin): !! Add test for this function.
it, err := ib.tagIndex.Get(ib.IfdIdentity(), tagId)
log.PanicIf(err)
bt := NewStandardBuilderTag(ib.IfdIdentity().UnindexedString(), it, ib.byteOrder, value)
i, err := ib.Find(tagId)
if err != nil {
if log.Is(err, ErrTagEntryNotFound) == false {
log.Panic(err)
}
ib.tags = append(ib.tags, bt)
} else {
ib.tags[i] = bt
}
return nil
}
// SetStandardWithName quickly and easily composes and adds or replaces the
// tag using the information already known about a tag (using the name). Only
// works with standard tags.
func (ib *IfdBuilder) SetStandardWithName(tagName string, value interface{}) (err error) {
defer func() {
if state := recover(); state != nil {
err = log.Wrap(state.(error))
}
}()
// TODO(dustin): !! Add test for this function.
it, err := ib.tagIndex.GetWithName(ib.IfdIdentity(), tagName)
log.PanicIf(err)
bt := NewStandardBuilderTag(ib.IfdIdentity().UnindexedString(), it, ib.byteOrder, value)
i, err := ib.Find(bt.tagId)
if err != nil {
if log.Is(err, ErrTagEntryNotFound) == false {
log.Panic(err)
}
ib.tags = append(ib.tags, bt)
} else {
ib.tags[i] = bt
}
return nil
}