ifd_builder_encode: Bugfixed next-IFD offsets.

- Affected sibling IFDs.
2018-05-05 02:01:18 -04:00 · 2018-05-05 02:01:18 -04:00 · 6c71ccf651
parent 887842e85a
commit 6c71ccf651
2 changed files with 86 additions and 166 deletions
--- a/ifd_builder_encode.go
+++ b/ifd_builder_encode.go
@ -2,7 +2,6 @@ package exif

 import (
    "bytes"
-    // "fmt"

    "encoding/binary"

@ -288,15 +287,18 @@ func (ibe *IfdByteEncoder) encodeIfdToBytes(ib *IfdBuilder, ifdAddressableOffset
    // N the link from this IFD to the next IFD that will be written in the
    // next cycle.
    if setNextIb == true {
-        nextIfdOffsetToWrite += dataSize
-        // fmt.Printf("SETTING NEXT-IFD FOR %s TO: (0x%04x)\n", ib.ii, nextIfdOffsetToWrite)
-    } else {
-        nextIfdOffsetToWrite = 0
-    }
+        // Write address of next IFD in chain. This will be the original
+        // allocation offset plus the size of everything we have allocated for
+        // this IFD and its child-IFDs.

-    // Write address of next IFD in chain.
-    err = bw.WriteUint32(nextIfdOffsetToWrite)
-    log.PanicIf(err)
+        offset := ifdAddressableOffset + dataSize
+
+        err := bw.WriteUint32(offset)
+        log.PanicIf(err)
+    } else {
+        err := bw.WriteUint32(0)
+        log.PanicIf(err)
+    }

    _, err = b.Write(dataBytes)
    log.PanicIf(err)
@ -336,8 +338,6 @@ func (ibe *IfdByteEncoder) encodeAndAttachIfd(ib *IfdBuilder, ifdAddressableOffs
    for thisIb := ib; thisIb != nil; thisIb = thisIb.nextIb {
        // Do a dry-run in order to pre-determine its size requirement.

-        // fmt.Printf("BUILDING IFD: %s   ifdAddressableOffset=(0x%04x)\n", ib.ii, ifdAddressableOffset)
-
        _, tableSize, allocatedDataSize, _, err := ibe.encodeIfdToBytes(ib, ifdAddressableOffset, 0, false)
        log.PanicIf(err)

--- a/ifd_builder_encode_test.go
+++ b/ifd_builder_encode_test.go
@ -5,6 +5,7 @@ import (
    "bytes"
    "reflect"
    "fmt"
+    "strings"

    "github.com/dsoprea/go-logging"
 )
@ -793,18 +794,18 @@ func Test_IfdByteEncoder_EncodeToExif_WithChildAndSibling(t *testing.T) {
    log.PanicIf(err)


-    // // Link to another IB (sibling relationship). The root/standard IFD may
-    // // occur twice in some JPEGs (for thumbnail or FlashPix images).
+    // Link to another IB (sibling relationship). The root/standard IFD may
+    // occur twice in some JPEGs (for thumbnail or FlashPix images).

-    // nextIb := NewIfdBuilder(RootIi, TestDefaultByteOrder)
+    nextIb := NewIfdBuilder(RootIi, TestDefaultByteOrder)

-    // err = nextIb.AddFromConfig(0x0101, []uint32 { 0x11223344 })
-    // log.PanicIf(err)
+    err = nextIb.AddFromConfig(0x0101, []uint32 { 0x11223344 })
+    log.PanicIf(err)

-    // err = nextIb.AddFromConfig(0x0102, []uint16 { 0x5566 })
-    // log.PanicIf(err)
+    err = nextIb.AddFromConfig(0x0102, []uint16 { 0x5566 })
+    log.PanicIf(err)

-    // ib.SetNextIb(nextIb)
+    ib.SetNextIb(nextIb)


    // Encode.
@ -824,184 +825,103 @@ func Test_IfdByteEncoder_EncodeToExif_WithChildAndSibling(t *testing.T) {

    tagsDump := index.RootIfd.DumpTree()

-    expected := []string {
-        "[ROOT]->[IFD] (0x000b)",
-        "[ROOT]->[IFD] (0x00ff)",
-        "[ROOT]->[IFD] (0x8769)",
-        "[IFD]->[Exif] (0x8827)",
-        "[IFD]->[Exif] (0x8833)",
-        "[ROOT]->[IFD] (0x0100)",
-        "[ROOT]->[IFD] (0x8825)",
-        "[IFD]->[GPSInfo] (0x0005)",
-        "[ROOT]->[IFD] (0x013e)",
-    }
+    actual := strings.Join(tagsDump, "\n")

-    if reflect.DeepEqual(tagsDump, expected) != true {
+    expected :=
+`> IFD [ROOT]->[IFD]:(0) TOP
+  - (0x000b)
+  - (0x00ff)
+  - (0x8769)
+  > IFD [IFD]->[Exif]:(0) TOP
+    - (0x8827)
+    - (0x8833)
+  < IFD [IFD]->[Exif]:(0) BOTTOM
+  - (0x0100)
+  - (0x8825)
+  > IFD [IFD]->[GPSInfo]:(0) TOP
+    - (0x0005)
+  < IFD [IFD]->[GPSInfo]:(0) BOTTOM
+  - (0x013e)
+< IFD [ROOT]->[IFD]:(0) BOTTOM
+* LINKING TO SIBLING IFD [IFD]:(1)
+> IFD [ROOT]->[IFD]:(1) TOP
+  - (0x8827)
+  - (0x8833)
+< IFD [ROOT]->[IFD]:(1) BOTTOM`
+
+    if actual != expected {
        fmt.Printf("\n")

        fmt.Printf("Actual:\n")
        fmt.Printf("\n")
-
-        for i, line := range tagsDump {
-            fmt.Printf("%d: %s\n", i, line)
-        }
-
+        fmt.Printf("%s\n", actual)
        fmt.Printf("\n")

        fmt.Printf("Expected:\n")
        fmt.Printf("\n")
-
-        for i, line := range expected {
-            fmt.Printf("%d: %s\n", i, line)
-        }
-
+        fmt.Printf("%s\n", expected)
        fmt.Printf("\n")

        t.Fatalf("IFD hierarchy not correct.")
    }
 }

-// func ExampleIfdByteEncoder_EncodeToExif() {
-//     // Construct an IFD.
+func ExampleIfdByteEncoder_EncodeToExif() {
+    // Construct an IFD.

-//     ib := NewIfdBuilder(RootIi, EncodeDefaultByteOrder)
+    ib := NewIfdBuilder(RootIi, EncodeDefaultByteOrder)

-//     err := ib.AddFromConfigWithName("ProcessingSoftware", "asciivalue")
-//     log.PanicIf(err)
+    err := ib.AddFromConfigWithName("ProcessingSoftware", "asciivalue")
+    log.PanicIf(err)

-//     err = ib.AddFromConfigWithName("DotRange", []uint8 { 0x11 })
-//     log.PanicIf(err)
+    err = ib.AddFromConfigWithName("DotRange", []uint8 { 0x11 })
+    log.PanicIf(err)

-//     err = ib.AddFromConfigWithName("SubfileType", []uint16 { 0x2233 })
-//     log.PanicIf(err)
+    err = ib.AddFromConfigWithName("SubfileType", []uint16 { 0x2233 })
+    log.PanicIf(err)

-//     err = ib.AddFromConfigWithName("ImageWidth", []uint32 { 0x44556677 })
-//     log.PanicIf(err)
+    err = ib.AddFromConfigWithName("ImageWidth", []uint32 { 0x44556677 })
+    log.PanicIf(err)

-//     err = ib.AddFromConfigWithName("WhitePoint", []Rational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
-//     log.PanicIf(err)
+    err = ib.AddFromConfigWithName("WhitePoint", []Rational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
+    log.PanicIf(err)

-//     err = ib.AddFromConfigWithName("ShutterSpeedValue", []SignedRational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
-//     log.PanicIf(err)
+    err = ib.AddFromConfigWithName("ShutterSpeedValue", []SignedRational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
+    log.PanicIf(err)


-//     // Encode it.
+    // Encode it.

-//     ibe := NewIfdByteEncoder()
+    ibe := NewIfdByteEncoder()

-//     exifData, err := ibe.EncodeToExif(ib)
-//     log.PanicIf(err)
+    exifData, err := ibe.EncodeToExif(ib)
+    log.PanicIf(err)


-//     // Parse it so we can see it.
+    // Parse it so we can see it.

-//     e := NewExif()
+    e := NewExif()

-//     _, index, err := e.Collect(exifData)
-//     log.PanicIf(err)
+    _, index, err := e.Collect(exifData)
+    log.PanicIf(err)

-//     // addressableData is the byte-slice where the allocated data can be
-//     // resolved (where position 0x0 will correlate with offset 0x0).
-//     addressableData := exifData[ExifAddressableAreaStart:]
+    // addressableData is the byte-slice where the allocated data can be
+    // resolved (where position 0x0 will correlate with offset 0x0).
+    addressableData := exifData[ExifAddressableAreaStart:]

-//     for i, e := range index.RootIfd.Entries {
-//         value, err := e.Value(addressableData, EncodeDefaultByteOrder)
-//         log.PanicIf(err)
+    for i, e := range index.RootIfd.Entries {
+        value, err := e.Value(addressableData, EncodeDefaultByteOrder)
+        log.PanicIf(err)

-//         fmt.Printf("%d: %s [%v]\n", i, e, value)
-//     }
+        fmt.Printf("%d: %s [%v]\n", i, e, value)
+    }

-//     // Output:
-//     //
-//     // 0: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x0b) TAG-TYPE=[ASCII] UNIT-COUNT=(11)> [asciivalue]
-//     // 1: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x150) TAG-TYPE=[BYTE] UNIT-COUNT=(1)> [[17]]
-//     // 2: IfdTagEntry<TAG-IFD=[] TAG-ID=(0xff) TAG-TYPE=[SHORT] UNIT-COUNT=(1)> [[8755]]
-//     // 3: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x100) TAG-TYPE=[LONG] UNIT-COUNT=(1)> [[1146447479]]
-//     // 4: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x13e) TAG-TYPE=[RATIONAL] UNIT-COUNT=(1)> [[{286335522 858997828}]]
-//     // 5: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x9201) TAG-TYPE=[SRATIONAL] UNIT-COUNT=(1)> [[{286335522 858997828}]]
-// }
-
-
-
-
-
-
-
-
-
-// func ExampleIfdByteEncoder_EncodeToExif_WithChild() {
-//     // Construct an IFD.
-
-//     ib := NewIfdBuilder(RootIi, EncodeDefaultByteOrder)
-
-//     err := ib.AddFromConfigWithName("ProcessingSoftware", "asciivalue")
-//     log.PanicIf(err)
-
-//     err = ib.AddFromConfigWithName("DotRange", []uint8 { 0x11 })
-//     log.PanicIf(err)
-
-//     err = ib.AddFromConfigWithName("SubfileType", []uint16 { 0x2233 })
-//     log.PanicIf(err)
-
-
-//     // Add a child IB right in the middle.
-
-//     childIb := NewIfdBuilder(ExifIi, EncodeDefaultByteOrder)
-
-//     err = childIb.AddFromConfigWithName("ISOSpeedRatings", []uint16 { 0x1122 })
-//     log.PanicIf(err)
-
-//     err = childIb.AddFromConfigWithName("ISOSpeed", []uint32 { 0x33445566 })
-//     log.PanicIf(err)
-
-//     err = ib.AddChildIb(childIb)
-//     log.PanicIf(err)
-
-
-//     err = ib.AddFromConfigWithName("ImageWidth", []uint32 { 0x44556677 })
-//     log.PanicIf(err)
-
-//     err = ib.AddFromConfigWithName("WhitePoint", []Rational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
-//     log.PanicIf(err)
-
-//     err = ib.AddFromConfigWithName("ShutterSpeedValue", []SignedRational { { Numerator: 0x11112222, Denominator: 0x33334444 } })
-//     log.PanicIf(err)
-
-
-//     // Encode it.
-
-//     ibe := NewIfdByteEncoder()
-
-//     exifData, err := ibe.EncodeToExif(ib)
-//     log.PanicIf(err)
-
-
-//     // Parse it so we can see it.
-
-//     e := NewExif()
-
-//     _, index, err := e.Collect(exifData)
-//     log.PanicIf(err)
-
-//     // addressableData is the byte-slice where the allocated data can be
-//     // resolved (where position 0x0 will correlate with offset 0x0).
-//     addressableData := exifData[ExifAddressableAreaStart:]
-
-//     for i, e := range index.RootIfd.Entries {
-//         value, err := e.Value(addressableData, EncodeDefaultByteOrder)
-//         log.PanicIf(err)
-
-//         fmt.Printf("%d: %s %v\n", i, e, value)
-//     }
-
-//     // Output:
-//     //
-//     // 0: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x0b) TAG-TYPE=[ASCII] UNIT-COUNT=(11)> asciivalue
-//     // 1: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x150) TAG-TYPE=[BYTE] UNIT-COUNT=(1)> [17]
-//     // 2: IfdTagEntry<TAG-IFD=[] TAG-ID=(0xff) TAG-TYPE=[SHORT] UNIT-COUNT=(1)> [8755]
-//     // 3: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x100) TAG-TYPE=[LONG] UNIT-COUNT=(1)> [1146447479]
-//     // 4: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x13e) TAG-TYPE=[RATIONAL] UNIT-COUNT=(1)> [{286335522 858997828}]
-//     // 5: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x9201) TAG-TYPE=[SRATIONAL] UNIT-COUNT=(1)> [{286335522 858997828}]
-// }
-
-// TODO(dustin): !! Write test with both chained and child IFDs
+    // Output:
+    //
+    // 0: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x0b) TAG-TYPE=[ASCII] UNIT-COUNT=(11)> [asciivalue]
+    // 1: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x150) TAG-TYPE=[BYTE] UNIT-COUNT=(1)> [[17]]
+    // 2: IfdTagEntry<TAG-IFD=[] TAG-ID=(0xff) TAG-TYPE=[SHORT] UNIT-COUNT=(1)> [[8755]]
+    // 3: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x100) TAG-TYPE=[LONG] UNIT-COUNT=(1)> [[1146447479]]
+    // 4: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x13e) TAG-TYPE=[RATIONAL] UNIT-COUNT=(1)> [[{286335522 858997828}]]
+    // 5: IfdTagEntry<TAG-IFD=[] TAG-ID=(0x9201) TAG-TYPE=[SRATIONAL] UNIT-COUNT=(1)> [[{286335522 858997828}]]
+}