gecko-dev/widget/nsHTMLFormatConverter.cpp
Neil Deakin 9c2e7458ba Bug 1776879, replace text/unicode for clipboard and drag and drop and use text/plain directly, r=edgar,mak,stransky,geckoview-reviewers,extension-reviewers,zombie,m_kato
Most usage is a straight replacement but gtk needs extra changes as it transfers plain text in UTF8 natively and needs to be converted into UTF16, and Windows uses single-byte characters for RTF and CF_HTML formats so we preserve this.

Differential Revision: https://phabricator.services.mozilla.com/D158587
2023-02-01 23:30:55 +00:00

185 lines
5.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsHTMLFormatConverter.h"
#include "nsArray.h"
#include "nsCRT.h"
#include "nsCOMPtr.h"
#include "nsITransferable.h"
#include "nsLiteralString.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
// HTML convertor stuff
#include "nsPrimitiveHelpers.h"
#include "nsIDocumentEncoder.h"
#include "nsContentUtils.h"
nsHTMLFormatConverter::nsHTMLFormatConverter() = default;
nsHTMLFormatConverter::~nsHTMLFormatConverter() = default;
NS_IMPL_ISUPPORTS(nsHTMLFormatConverter, nsIFormatConverter)
//
// GetInputDataFlavors
//
// Creates a new list and returns the list of all the flavors this converter
// knows how to import. In this case, it's just HTML.
//
NS_IMETHODIMP
nsHTMLFormatConverter::GetInputDataFlavors(nsTArray<nsCString>& aFlavors) {
aFlavors.AppendElement(nsLiteralCString(kHTMLMime));
return NS_OK;
}
//
// GetOutputDataFlavors
//
// Creates a new list and returns the list of all the flavors this converter
// knows how to export (convert). In this case, it's all sorts of things that
// HTML can be converted to.
//
NS_IMETHODIMP
nsHTMLFormatConverter::GetOutputDataFlavors(nsTArray<nsCString>& aFlavors) {
aFlavors.AppendElement(nsLiteralCString(kHTMLMime));
aFlavors.AppendElement(nsLiteralCString(kTextMime));
return NS_OK;
}
//
// CanConvert
//
// Determines if we support the given conversion. Currently, this method only
// converts from HTML to others.
//
NS_IMETHODIMP
nsHTMLFormatConverter::CanConvert(const char* aFromDataFlavor,
const char* aToDataFlavor, bool* _retval) {
if (!_retval) return NS_ERROR_INVALID_ARG;
*_retval = false;
if (!nsCRT::strcmp(aFromDataFlavor, kHTMLMime)) {
if (!nsCRT::strcmp(aToDataFlavor, kHTMLMime)) {
*_retval = true;
} else if (!nsCRT::strcmp(aToDataFlavor, kTextMime)) {
*_retval = true;
}
#if NOT_NOW
// pinkerton
// no one uses this flavor right now, so it's just slowing things down. If
// anyone cares I can put it back in.
else if (toFlavor.Equals(kAOLMailMime))
*_retval = true;
#endif
}
return NS_OK;
} // CanConvert
//
// Convert
//
// Convert data from one flavor to another. The data is wrapped in primitive
// objects so that it is accessible from JS. Currently, this only accepts HTML
// input, so anything else is invalid.
//
// XXX This method copies the data WAAAAY too many time for my liking. Grrrrrr.
// Mostly it's because
// XXX we _must_ put things into nsStrings so that the parser will accept it.
// Lame lame lame lame. We
// XXX also can't just get raw unicode out of the nsString, so we have to
// allocate heap to get
// XXX unicode out of the string. Lame lame lame.
//
NS_IMETHODIMP
nsHTMLFormatConverter::Convert(const char* aFromDataFlavor,
nsISupports* aFromData,
const char* aToDataFlavor,
nsISupports** aToData) {
if (!aToData) return NS_ERROR_INVALID_ARG;
nsresult rv = NS_OK;
*aToData = nullptr;
if (!nsCRT::strcmp(aFromDataFlavor, kHTMLMime)) {
nsAutoCString toFlavor(aToDataFlavor);
// HTML on clipboard is going to always be double byte so it will be in a
// primitive class of nsISupportsString. Also, since the data is in two byte
// chunks the length represents the length in 1-byte chars, so we need to
// divide by two.
nsCOMPtr<nsISupportsString> dataWrapper0(do_QueryInterface(aFromData));
if (!dataWrapper0) {
return NS_ERROR_INVALID_ARG;
}
nsAutoString dataStr;
dataWrapper0->GetData(dataStr); // COPY #1
// note: conversion to text/plain is done inside the clipboard. we do not
// need to worry about it here.
if (toFlavor.Equals(kHTMLMime) || toFlavor.Equals(kTextMime)) {
nsresult res;
if (toFlavor.Equals(kHTMLMime)) {
int32_t dataLen = dataStr.Length() * 2;
nsPrimitiveHelpers::CreatePrimitiveForData(toFlavor, dataStr.get(),
dataLen, aToData);
} else {
nsAutoString outStr;
res = ConvertFromHTMLToUnicode(dataStr, outStr);
if (NS_SUCCEEDED(res)) {
int32_t dataLen = outStr.Length() * 2;
nsPrimitiveHelpers::CreatePrimitiveForData(toFlavor, outStr.get(),
dataLen, aToData);
}
}
} // else if HTML or Unicode
else if (toFlavor.Equals(kAOLMailMime)) {
nsAutoString outStr;
if (NS_SUCCEEDED(ConvertFromHTMLToAOLMail(dataStr, outStr))) {
int32_t dataLen = outStr.Length() * 2;
nsPrimitiveHelpers::CreatePrimitiveForData(toFlavor, outStr.get(),
dataLen, aToData);
}
} // else if AOL mail
else {
rv = NS_ERROR_FAILURE;
}
} // if we got html mime
else
rv = NS_ERROR_FAILURE;
return rv;
} // Convert
//
// ConvertFromHTMLToUnicode
//
// Takes HTML and converts it to plain text but in unicode.
//
NS_IMETHODIMP
nsHTMLFormatConverter::ConvertFromHTMLToUnicode(const nsAutoString& aFromStr,
nsAutoString& aToStr) {
return nsContentUtils::ConvertToPlainText(
aFromStr, aToStr,
nsIDocumentEncoder::OutputSelectionOnly |
nsIDocumentEncoder::OutputAbsoluteLinks |
nsIDocumentEncoder::OutputNoScriptContent |
nsIDocumentEncoder::OutputNoFramesContent,
0);
} // ConvertFromHTMLToUnicode
NS_IMETHODIMP
nsHTMLFormatConverter::ConvertFromHTMLToAOLMail(const nsAutoString& aFromStr,
nsAutoString& aToStr) {
aToStr.AssignLiteral("<HTML>");
aToStr.Append(aFromStr);
aToStr.AppendLiteral("</HTML>");
return NS_OK;
}