diff options
Diffstat (limited to 'vendor/github.com/dsoprea/go-exif/parser.go')
-rw-r--r-- | vendor/github.com/dsoprea/go-exif/parser.go | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/vendor/github.com/dsoprea/go-exif/parser.go b/vendor/github.com/dsoprea/go-exif/parser.go new file mode 100644 index 000000000..4702db2f8 --- /dev/null +++ b/vendor/github.com/dsoprea/go-exif/parser.go @@ -0,0 +1,190 @@ +package exif + +import ( + "bytes" + + "encoding/binary" + + "github.com/dsoprea/go-logging" +) + +type Parser struct { +} + +func (p *Parser) ParseBytes(data []byte, unitCount uint32) (value []uint8, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeByte.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + value = []uint8(data[:count]) + + return value, nil +} + +// ParseAscii returns a string and auto-strips the trailing NUL character. +func (p *Parser) ParseAscii(data []byte, unitCount uint32) (value string, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeAscii.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + if len(data) == 0 || data[count-1] != 0 { + s := string(data[:count]) + typeLogger.Warningf(nil, "ascii not terminated with nul as expected: [%v]", s) + + return s, nil + } else { + // Auto-strip the NUL from the end. It serves no purpose outside of + // encoding semantics. + + return string(data[:count-1]), nil + } +} + +// ParseAsciiNoNul returns a string without any consideration for a trailing NUL +// character. +func (p *Parser) ParseAsciiNoNul(data []byte, unitCount uint32) (value string, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeAscii.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + return string(data[:count]), nil +} + +func (p *Parser) ParseShorts(data []byte, unitCount uint32, byteOrder binary.ByteOrder) (value []uint16, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeShort.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + value = make([]uint16, count) + for i := 0; i < count; i++ { + value[i] = byteOrder.Uint16(data[i*2:]) + } + + return value, nil +} + +func (p *Parser) ParseLongs(data []byte, unitCount uint32, byteOrder binary.ByteOrder) (value []uint32, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeLong.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + value = make([]uint32, count) + for i := 0; i < count; i++ { + value[i] = byteOrder.Uint32(data[i*4:]) + } + + return value, nil +} + +func (p *Parser) ParseRationals(data []byte, unitCount uint32, byteOrder binary.ByteOrder) (value []Rational, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeRational.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + value = make([]Rational, count) + for i := 0; i < count; i++ { + value[i].Numerator = byteOrder.Uint32(data[i*8:]) + value[i].Denominator = byteOrder.Uint32(data[i*8+4:]) + } + + return value, nil +} + +func (p *Parser) ParseSignedLongs(data []byte, unitCount uint32, byteOrder binary.ByteOrder) (value []int32, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeSignedLong.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + b := bytes.NewBuffer(data) + + value = make([]int32, count) + for i := 0; i < count; i++ { + err := binary.Read(b, byteOrder, &value[i]) + log.PanicIf(err) + } + + return value, nil +} + +func (p *Parser) ParseSignedRationals(data []byte, unitCount uint32, byteOrder binary.ByteOrder) (value []SignedRational, err error) { + defer func() { + if state := recover(); state != nil { + err = log.Wrap(state.(error)) + } + }() + + count := int(unitCount) + + if len(data) < (TypeSignedRational.Size() * count) { + log.Panic(ErrNotEnoughData) + } + + b := bytes.NewBuffer(data) + + value = make([]SignedRational, count) + for i := 0; i < count; i++ { + err = binary.Read(b, byteOrder, &value[i].Numerator) + log.PanicIf(err) + + err = binary.Read(b, byteOrder, &value[i].Denominator) + log.PanicIf(err) + } + + return value, nil +} |