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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* nsIContentSerializer implementation that can be used with an
* nsIDocumentEncoder to convert an XML DOM to an XML string that
* could be parsed into more or less the original DOM.
*/
#ifndef nsXMLContentSerializer_h__
#define nsXMLContentSerializer_h__
#include "mozilla/Attributes.h"
#include "nsIContentSerializer.h"
#include "nsISupportsUtils.h"
#include "nsCOMPtr.h"
#include "nsTArray.h"
#include "nsString.h"
#define kIndentStr u" "_ns
#define kEndTag u"</"_ns
class nsAtom;
class nsINode;
namespace mozilla {
class Encoding;
}
class nsXMLContentSerializer : public nsIContentSerializer {
public:
nsXMLContentSerializer();
NS_DECL_ISUPPORTS
NS_IMETHOD Init(uint32_t flags, uint32_t aWrapColumn,
const mozilla::Encoding* aEncoding, bool aIsCopying,
bool aRewriteEncodingDeclaration,
bool* aNeedsPreformatScanning, nsAString& aOutput) override;
NS_IMETHOD AppendText(nsIContent* aText, int32_t aStartOffset,
int32_t aEndOffset) override;
NS_IMETHOD AppendCDATASection(nsIContent* aCDATASection, int32_t aStartOffset,
int32_t aEndOffset) override;
NS_IMETHOD AppendProcessingInstruction(
mozilla::dom::ProcessingInstruction* aPI, int32_t aStartOffset,
int32_t aEndOffset) override;
NS_IMETHOD AppendComment(mozilla::dom::Comment* aComment,
int32_t aStartOffset, int32_t aEndOffset) override;
NS_IMETHOD AppendDoctype(mozilla::dom::DocumentType* aDoctype) override;
NS_IMETHOD AppendElementStart(
mozilla::dom::Element* aElement,
mozilla::dom::Element* aOriginalElement) override;
NS_IMETHOD AppendElementEnd(mozilla::dom::Element* aElement,
mozilla::dom::Element* aOriginalElement) override;
NS_IMETHOD FlushAndFinish() override { return NS_OK; }
NS_IMETHOD Finish() override;
NS_IMETHOD GetOutputLength(uint32_t& aLength) const override;
NS_IMETHOD AppendDocumentStart(mozilla::dom::Document* aDocument) override;
NS_IMETHOD ScanElementForPreformat(mozilla::dom::Element* aElement) override {
return NS_OK;
}
NS_IMETHOD ForgetElementForPreformat(
mozilla::dom::Element* aElement) override {
return NS_OK;
}
protected:
virtual ~nsXMLContentSerializer();
/**
* Appends a char16_t character and increments the column position
*/
[[nodiscard]] bool AppendToString(const char16_t aChar,
nsAString& aOutputStr);
/**
* Appends a nsAString string and increments the column position
*/
[[nodiscard]] bool AppendToString(const nsAString& aStr,
nsAString& aOutputStr);
/**
* Appends a string by replacing all line-endings
* by mLineBreak, except in the case of raw output.
* It increments the column position.
*/
[[nodiscard]] bool AppendToStringConvertLF(const nsAString& aStr,
nsAString& aOutputStr);
/**
* Appends a string by wrapping it when necessary.
* It updates the column position.
*/
[[nodiscard]] bool AppendToStringWrapped(const nsAString& aStr,
nsAString& aOutputStr);
/**
* Appends a string by formating and wrapping it when necessary
* It updates the column position.
*/
[[nodiscard]] bool AppendToStringFormatedWrapped(const nsAString& aStr,
nsAString& aOutputStr);
// used by AppendToStringWrapped
[[nodiscard]] bool AppendWrapped_WhitespaceSequence(
nsAString::const_char_iterator& aPos,
const nsAString::const_char_iterator aEnd,
const nsAString::const_char_iterator aSequenceStart,
nsAString& aOutputStr);
// used by AppendToStringFormatedWrapped
[[nodiscard]] bool AppendFormatedWrapped_WhitespaceSequence(
nsAString::const_char_iterator& aPos,
const nsAString::const_char_iterator aEnd,
const nsAString::const_char_iterator aSequenceStart,
bool& aMayIgnoreStartOfLineWhitespaceSequence, nsAString& aOutputStr);
// used by AppendToStringWrapped and AppendToStringFormatedWrapped
[[nodiscard]] bool AppendWrapped_NonWhitespaceSequence(
nsAString::const_char_iterator& aPos,
const nsAString::const_char_iterator aEnd,
const nsAString::const_char_iterator aSequenceStart,
bool& aMayIgnoreStartOfLineWhitespaceSequence,
bool& aSequenceStartAfterAWhiteSpace, nsAString& aOutputStr);
/**
* add mLineBreak to the string
* It updates the column position and other flags.
*/
[[nodiscard]] bool AppendNewLineToString(nsAString& aOutputStr);
/**
* Appends a string by translating entities
* It doesn't increment the column position
*/
[[nodiscard]] virtual bool AppendAndTranslateEntities(const nsAString& aStr,
nsAString& aOutputStr);
/**
* Helper for virtual AppendAndTranslateEntities that does the actualy work.
*
* Do not call this directly. Call it via the template helper below.
*/
private:
[[nodiscard]] static bool AppendAndTranslateEntities(
const nsAString& aStr, nsAString& aOutputStr,
const uint8_t aEntityTable[], uint16_t aMaxTableIndex,
const char* const aStringTable[]);
protected:
/**
* Helper for calling AppendAndTranslateEntities in a way that guarantees we
* don't mess up our aEntityTable sizing. This is a bit more complicated than
* it could be, becaue sometimes we don't want to use all of aEntityTable, so
* we have to allow passing the amount to use independently. But we can
* statically ensure it's not too big.
*
* The first integer template argument, which callers need to specify
* explicitly, is the index of the last entry in aEntityTable that should be
* considered for encoding as an entity reference. The second integer
* argument will be deduced from the actual table passed in.
*
* aEntityTable contains as values indices into aStringTable. Those represent
* the strings that should be used to replace the characters that are used to
* index into aEntityTable. aStringTable[0] should be nullptr, and characters
* that do not need replacement should map to 0 in aEntityTable.
*/
template <uint16_t LargestIndex, uint16_t TableLength>
[[nodiscard]] bool AppendAndTranslateEntities(
const nsAString& aStr, nsAString& aOutputStr,
const uint8_t (&aEntityTable)[TableLength],
const char* const aStringTable[]) {
static_assert(LargestIndex < TableLength,
"Largest allowed index must be smaller than table length");
return AppendAndTranslateEntities(aStr, aOutputStr, aEntityTable,
LargestIndex, aStringTable);
}
/**
* Max index that can be used with some of our entity tables.
*/
static const uint16_t kGTVal = 62;
/**
* retrieve the text content of the node and append it to the given string
* It doesn't increment the column position
*/
nsresult AppendTextData(nsIContent* aNode, int32_t aStartOffset,
int32_t aEndOffset, nsAString& aStr,
bool aTranslateEntities);
virtual nsresult PushNameSpaceDecl(const nsAString& aPrefix,
const nsAString& aURI, nsIContent* aOwner);
void PopNameSpaceDeclsFor(nsIContent* aOwner);
/**
* The problem that ConfirmPrefix fixes is that anyone can insert nodes
* through the DOM that have a namespace URI and a random or empty or
* previously existing prefix that's totally unrelated to the prefixes
* declared at that point through xmlns attributes. So what ConfirmPrefix
* does is ensure that we can map aPrefix to the namespace URI aURI (for
* example, that the prefix is not already mapped to some other namespace).
* aPrefix will be adjusted, if necessary, so the value of the prefix
* _after_ this call is what should be serialized.
* @param aPrefix the prefix that may need adjusting
* @param aURI the namespace URI we want aPrefix to point to
* @param aElement the element we're working with (needed for proper default
* namespace handling)
* @param aIsAttribute true if we're confirming a prefix for an attribute.
* @return true if we need to push the (prefix, uri) pair on the namespace
* stack (note that this can happen even if the prefix is
* empty).
*/
bool ConfirmPrefix(nsAString& aPrefix, const nsAString& aURI,
nsIContent* aElement, bool aIsAttribute);
/**
* GenerateNewPrefix generates a new prefix and writes it to aPrefix
*/
void GenerateNewPrefix(nsAString& aPrefix);
uint32_t ScanNamespaceDeclarations(mozilla::dom::Element* aContent,
mozilla::dom::Element* aOriginalElement,
const nsAString& aTagNamespaceURI);
[[nodiscard]] virtual bool SerializeAttributes(
mozilla::dom::Element* aContent, mozilla::dom::Element* aOriginalElement,
nsAString& aTagPrefix, const nsAString& aTagNamespaceURI,
nsAtom* aTagName, nsAString& aStr, uint32_t aSkipAttr, bool aAddNSAttr);
[[nodiscard]] bool SerializeAttr(const nsAString& aPrefix,
const nsAString& aName,
const nsAString& aValue, nsAString& aStr,
bool aDoEscapeEntities);
bool IsJavaScript(nsIContent* aContent, nsAtom* aAttrNameAtom,
int32_t aAttrNamespaceID, const nsAString& aValueString);
/**
* This method can be redefined to check if the element can be serialized.
* It is called when the serialization of the start tag is asked
* (AppendElementStart)
* In this method you can also force the formating
* by setting aForceFormat to true.
* @return boolean true if the element can be output
*/
virtual bool CheckElementStart(mozilla::dom::Element* aElement,
bool& aForceFormat, nsAString& aStr,
nsresult& aResult);
/**
* This method is responsible for appending the '>' at the end of the start
* tag, possibly preceded by '/' and maybe a ' ' before that too.
*
* aElement and aOriginalElement are the same as the corresponding arguments
* to AppendElementStart.
*/
[[nodiscard]] bool AppendEndOfElementStart(
mozilla::dom::Element* aEleemnt, mozilla::dom::Element* aOriginalElement,
nsAString& aStr);
/**
* This method can be redefine to serialize additional things just after
* the serialization of the start tag.
* (called at the end of AppendElementStart)
*/
[[nodiscard]] virtual bool AfterElementStart(nsIContent* aContent,
nsIContent* aOriginalElement,
nsAString& aStr) {
return true;
};
/**
* This method can be redefined to check if the element can be serialized.
* It is called when the serialization of the end tag is asked
* (AppendElementEnd)
* In this method you can also force the formating
* by setting aForceFormat to true.
* @return boolean true if the element can be output
*/
virtual bool CheckElementEnd(mozilla::dom::Element* aElement,
mozilla::dom::Element* aOriginalElement,
bool& aForceFormat, nsAString& aStr);
/**
* This method can be redefine to serialize additional things just after
* the serialization of the end tag.
* (called at the end of AppendElementStart)
*/
virtual void AfterElementEnd(nsIContent* aContent, nsAString& aStr){};
/**
* Returns true if a line break should be inserted before an element open tag
*/
virtual bool LineBreakBeforeOpen(int32_t aNamespaceID, nsAtom* aName);
/**
* Returns true if a line break should be inserted after an element open tag
*/
virtual bool LineBreakAfterOpen(int32_t aNamespaceID, nsAtom* aName);
/**
* Returns true if a line break should be inserted after an element close tag
*/
virtual bool LineBreakBeforeClose(int32_t aNamespaceID, nsAtom* aName);
/**
* Returns true if a line break should be inserted after an element close tag
*/
virtual bool LineBreakAfterClose(int32_t aNamespaceID, nsAtom* aName);
/**
* add intendation. Call only in the case of formating and if the current
* position is at 0. It updates the column position.
*/
[[nodiscard]] bool AppendIndentation(nsAString& aStr);
[[nodiscard]] bool IncrIndentation(nsAtom* aName);
void DecrIndentation(nsAtom* aName);
// Functions to check for newlines that needs to be added between nodes in
// the root of a document. See mAddNewlineForRootNode
[[nodiscard]] bool MaybeAddNewlineForRootNode(nsAString& aStr);
void MaybeFlagNewlineForRootNode(nsINode* aNode);
// Functions to check if we enter in or leave from a preformated content
virtual void MaybeEnterInPreContent(nsIContent* aNode);
virtual void MaybeLeaveFromPreContent(nsIContent* aNode);
bool ShouldMaintainPreLevel() const;
int32_t PreLevel() const {
MOZ_ASSERT(ShouldMaintainPreLevel());
return mPreLevel;
}
int32_t& PreLevel() {
MOZ_ASSERT(ShouldMaintainPreLevel());
return mPreLevel;
}
bool MaybeSerializeIsValue(mozilla::dom::Element* aElement, nsAString& aStr);
int32_t mPrefixIndex;
struct NameSpaceDecl {
nsString mPrefix;
nsString mURI;
nsIContent* mOwner;
};
nsTArray<NameSpaceDecl> mNameSpaceStack;
// nsIDocumentEncoder flags
MOZ_INIT_OUTSIDE_CTOR uint32_t mFlags;
// characters to use for line break
nsString mLineBreak;
// The charset that was passed to Init()
nsCString mCharset;
// current column position on the current line
uint32_t mColPos;
// true = pretty formating should be done (OutputFormated flag)
MOZ_INIT_OUTSIDE_CTOR bool mDoFormat;
// true = no formatting,(OutputRaw flag)
// no newline convertion and no rewrap long lines even if OutputWrap is set.
MOZ_INIT_OUTSIDE_CTOR bool mDoRaw;
// true = wrapping should be done (OutputWrap flag)
MOZ_INIT_OUTSIDE_CTOR bool mDoWrap;
// true = we can break lines (OutputDisallowLineBreaking flag)
MOZ_INIT_OUTSIDE_CTOR bool mAllowLineBreaking;
// number of maximum column in a line, in the wrap mode
MOZ_INIT_OUTSIDE_CTOR uint32_t mMaxColumn;
// current indent value
nsString mIndent;
// this is the indentation level after the indentation reached
// the maximum length of indentation
int32_t mIndentOverflow;
// says if the indentation has been already added on the current line
bool mIsIndentationAddedOnCurrentLine;
// the string which is currently added is in an attribute
bool mInAttribute;
// true = a newline character should be added. It's only
// useful when serializing root nodes. see MaybeAddNewlineForRootNode and
// MaybeFlagNewlineForRootNode
bool mAddNewlineForRootNode;
// Indicates that a space will be added if and only if content is
// continued on the same line while serializing source. Otherwise,
// the newline character acts as the whitespace and no space is needed.
// used when mDoFormat = true
bool mAddSpace;
// says that if the next string to add contains a newline character at the
// begining, then this newline character should be ignored, because a
// such character has already been added into the output string
bool mMayIgnoreLineBreakSequence;
bool mBodyOnly;
int32_t mInBody;
// Non-owning.
nsAString* mOutput;
private:
// number of nested elements which have preformated content
MOZ_INIT_OUTSIDE_CTOR int32_t mPreLevel;
static const uint8_t kEntities[];
static const uint8_t kAttrEntities[];
static const char* const kEntityStrings[];
};
nsresult NS_NewXMLContentSerializer(nsIContentSerializer** aSerializer);
#endif