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Address more golint recommendations #89

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This commit is contained in:
Gunnsteinn Hall 2017-08-02 18:01:31 +00:00
parent 2ecf2acce5
commit 714b4bcb60
3 changed files with 38 additions and 17 deletions
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34
pdf/core/crossrefs.go
View File

@ -25,10 +25,10 @@ const (
XREF_OBJECT_STREAM = iota
)
// Either can be in a normal xref table, or in an xref stream.
// Can point either to a file offset, or to an object stream.
// XrefFileOffset or XrefObjectStream...
// XrefObject defines a cross reference entry which is a map between object number (with generation number) and the
// location of the actual object, either as a file offset (xref table entry), or as a location within an xref
// stream object (xref object stream).
// TODO (v3): Unexport.
type XrefObject struct {
xtype int
objectNumber int
@ -40,16 +40,26 @@ type XrefObject struct {
osObjIndex int
}
// XrefTable is a map between object number and corresponding XrefObject.
// TODO (v3): Unexport.
type XrefTable map[int]XrefObject
// ObjectStream represents an object stream's information which can contain multiple indirect objects.
// The information specifies the number of objects and has information about offset locations for
// each object.
// TODO (v3): Unexport.
type ObjectStream struct {
N int
N int // TODO (v3): Unexport.
ds []byte
offsets map[int]int64
}
// ObjectStreams defines a map between object numbers (object streams only) and underlying ObjectStream information.
type ObjectStreams map[int]ObjectStream
// ObjectCache defines a map between object numbers and corresponding PdfObject. Serves as a cache for PdfObjects that
// have already been parsed.
// TODO (v3): Unexport.
type ObjectCache map[int]PdfObject
// Get an object from an object stream.
@ -114,7 +124,7 @@ func (this *PdfParser) lookupObjectViaOS(sobjNumber int, objNum int) (PdfObject,
common.Log.Trace("Parsing offset map")
// Load the offset map (relative to the beginning of the stream...)
var offsets map[int]int64 = make(map[int]int64)
offsets := map[int]int64{}
// Object list and offsets.
for i := 0; i < int(*N); i++ {
this.skipSpaces()
@ -182,11 +192,10 @@ func (this *PdfParser) lookupObjectViaOS(sobjNumber int, objNum int) (PdfObject,
return &io, nil
}
// Currently a bit messy.. multiple wrappers. Can we clean up?
// Outside interface for lookupByNumberWrapper. Default attempts
// repairs of bad xref tables.
// LookupByNumber looks up a PdfObject by object number. Returns an error on failure.
// TODO (v3): Unexport.
func (this *PdfParser) LookupByNumber(objNumber int) (PdfObject, error) {
// Outside interface for lookupByNumberWrapper. Default attempts repairs of bad xref tables.
obj, _, err := this.lookupByNumberWrapper(objNumber, true)
return obj, err
}
@ -318,13 +327,14 @@ func (this *PdfParser) lookupByNumber(objNumber int, attemptRepairs bool) (PdfOb
return nil, false, errors.New("Unknown xref type")
}
// LookupByReference
// LookupByReference looks up a PdfObject by a reference.
func (this *PdfParser) LookupByReference(ref PdfObjectReference) (PdfObject, error) {
common.Log.Trace("Looking up reference %s", ref.String())
return this.LookupByNumber(int(ref.ObjectNumber))
}
// Trace to direct object.
// Trace traces a PdfObject to direct object, looking up and resolving references as needed (unlike TraceToDirect).
// TODO (v3): Unexport.
func (this *PdfParser) Trace(obj PdfObject) (PdfObject, error) {
ref, isRef := obj.(*PdfObjectReference)
if !isRef {

9
pdf/core/stream.go
View File

@ -11,7 +11,7 @@ import (
"github.com/unidoc/unidoc/common"
)
// Creates the encoder from the stream's dictionary.
// NewEncoderFromStream creates a StreamEncoder based on the stream's dictionary.
func NewEncoderFromStream(streamObj *PdfObjectStream) (StreamEncoder, error) {
filterObj := streamObj.PdfObjectDictionary.Get("Filter")
if filterObj == nil {
@ -71,8 +71,8 @@ func NewEncoderFromStream(streamObj *PdfObjectStream) (StreamEncoder, error) {
}
}
// Decodes the stream.
// Supports FlateDecode, ASCIIHexDecode, LZW.
// DecodeStream decodes the stream data and returns the decoded data.
// An error is returned upon failure.
func DecodeStream(streamObj *PdfObjectStream) ([]byte, error) {
common.Log.Trace("Decode stream")
@ -92,8 +92,7 @@ func DecodeStream(streamObj *PdfObjectStream) ([]byte, error) {
return decoded, nil
}
// Encodes the stream.
// Uses the encoding specified by the object.
// EncodeStream encodes the stream data using the encoded specified by the stream's dictionary.
func EncodeStream(streamObj *PdfObjectStream) error {
common.Log.Trace("Encode stream")

12
pdf/core/symbols.go
View File

@ -5,6 +5,8 @@
package core
// IsWhiteSpace checks if byte represents a white space character.
// TODO (v3): Unexport.
func IsWhiteSpace(ch byte) bool {
// Table 1 white-space characters (7.2.2 Character Set)
// spaceCharacters := string([]byte{0x00, 0x09, 0x0A, 0x0C, 0x0D, 0x20})
@ -15,10 +17,14 @@ func IsWhiteSpace(ch byte) bool {
}
}
// IsFloatDigit checks if a character can be a part of a float number string.
// TODO (v3): Unexport.
func IsFloatDigit(c byte) bool {
return ('0' <= c && c <= '9') || c == '.'
}
// IsDecimalDigit checks if the character is a part of a decimal number string.
// TODO (v3): Unexport.
func IsDecimalDigit(c byte) bool {
if c >= '0' && c <= '9' {
return true
@ -27,6 +33,8 @@ func IsDecimalDigit(c byte) bool {
}
}
// IsOctalDigit checks if a character can be part of an octal digit string.
// TODO (v3): Unexport.
func IsOctalDigit(c byte) bool {
if c >= '0' && c <= '7' {
return true
@ -35,8 +43,10 @@ func IsOctalDigit(c byte) bool {
}
}
// IsPrintable checks if a character is printable.
// Regular characters that are outside the range EXCLAMATION MARK(21h)
// (!) to TILDE (7Eh) (~) should be written using the hexadecimal notation.
// TODO (v3): Unexport.
func IsPrintable(char byte) bool {
if char < 0x21 || char > 0x7E {
return false
@ -44,6 +54,8 @@ func IsPrintable(char byte) bool {
return true
}
// IsDelimiter checks if a character represents a delimiter.
// TODO (v3): Unexport.
func IsDelimiter(char byte) bool {
if char == '(' || char == ')' {
return true