1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/io/nsStringStream.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,407 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* vim:set ts=4 sts=4 sw=4 cin et: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +/**
1.11 + * Based on original code from nsIStringStream.cpp
1.12 + */
1.13 +
1.14 +#include "ipc/IPCMessageUtils.h"
1.15 +
1.16 +#include "nsStringStream.h"
1.17 +#include "nsStreamUtils.h"
1.18 +#include "nsReadableUtils.h"
1.19 +#include "nsISeekableStream.h"
1.20 +#include "nsISupportsPrimitives.h"
1.21 +#include "nsCRT.h"
1.22 +#include "prerror.h"
1.23 +#include "plstr.h"
1.24 +#include "nsIClassInfoImpl.h"
1.25 +#include "mozilla/Attributes.h"
1.26 +#include "mozilla/ipc/InputStreamUtils.h"
1.27 +#include "nsIIPCSerializableInputStream.h"
1.28 +
1.29 +using namespace mozilla::ipc;
1.30 +
1.31 +//-----------------------------------------------------------------------------
1.32 +// nsIStringInputStream implementation
1.33 +//-----------------------------------------------------------------------------
1.34 +
1.35 +class nsStringInputStream MOZ_FINAL : public nsIStringInputStream
1.36 + , public nsISeekableStream
1.37 + , public nsISupportsCString
1.38 + , public nsIIPCSerializableInputStream
1.39 +{
1.40 +public:
1.41 + NS_DECL_THREADSAFE_ISUPPORTS
1.42 + NS_DECL_NSIINPUTSTREAM
1.43 + NS_DECL_NSISTRINGINPUTSTREAM
1.44 + NS_DECL_NSISEEKABLESTREAM
1.45 + NS_DECL_NSISUPPORTSPRIMITIVE
1.46 + NS_DECL_NSISUPPORTSCSTRING
1.47 + NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
1.48 +
1.49 + nsStringInputStream()
1.50 + {
1.51 + Clear();
1.52 + }
1.53 +
1.54 +private:
1.55 + ~nsStringInputStream()
1.56 + {}
1.57 +
1.58 + uint32_t Length() const
1.59 + {
1.60 + return mData.Length();
1.61 + }
1.62 +
1.63 + uint32_t LengthRemaining() const
1.64 + {
1.65 + return Length() - mOffset;
1.66 + }
1.67 +
1.68 + void Clear()
1.69 + {
1.70 + mData.SetIsVoid(true);
1.71 + }
1.72 +
1.73 + bool Closed()
1.74 + {
1.75 + return mData.IsVoid();
1.76 + }
1.77 +
1.78 + nsDependentCSubstring mData;
1.79 + uint32_t mOffset;
1.80 +};
1.81 +
1.82 +// This class needs to support threadsafe refcounting since people often
1.83 +// allocate a string stream, and then read it from a background thread.
1.84 +NS_IMPL_ADDREF(nsStringInputStream)
1.85 +NS_IMPL_RELEASE(nsStringInputStream)
1.86 +
1.87 +NS_IMPL_CLASSINFO(nsStringInputStream, nullptr, nsIClassInfo::THREADSAFE,
1.88 + NS_STRINGINPUTSTREAM_CID)
1.89 +NS_IMPL_QUERY_INTERFACE_CI(nsStringInputStream,
1.90 + nsIStringInputStream,
1.91 + nsIInputStream,
1.92 + nsISupportsCString,
1.93 + nsISeekableStream,
1.94 + nsIIPCSerializableInputStream)
1.95 +NS_IMPL_CI_INTERFACE_GETTER(nsStringInputStream,
1.96 + nsIStringInputStream,
1.97 + nsIInputStream,
1.98 + nsISupportsCString,
1.99 + nsISeekableStream)
1.100 +
1.101 +/////////
1.102 +// nsISupportsCString implementation
1.103 +/////////
1.104 +
1.105 +NS_IMETHODIMP
1.106 +nsStringInputStream::GetType(uint16_t *type)
1.107 +{
1.108 + *type = TYPE_CSTRING;
1.109 + return NS_OK;
1.110 +}
1.111 +
1.112 +NS_IMETHODIMP
1.113 +nsStringInputStream::GetData(nsACString &data)
1.114 +{
1.115 + // The stream doesn't have any data when it is closed. We could fake it
1.116 + // and return an empty string here, but it seems better to keep this return
1.117 + // value consistent with the behavior of the other 'getter' methods.
1.118 + if (NS_WARN_IF(Closed()))
1.119 + return NS_BASE_STREAM_CLOSED;
1.120 +
1.121 + data.Assign(mData);
1.122 + return NS_OK;
1.123 +}
1.124 +
1.125 +NS_IMETHODIMP
1.126 +nsStringInputStream::SetData(const nsACString &data)
1.127 +{
1.128 + mData.Assign(data);
1.129 + mOffset = 0;
1.130 + return NS_OK;
1.131 +}
1.132 +
1.133 +NS_IMETHODIMP
1.134 +nsStringInputStream::ToString(char **result)
1.135 +{
1.136 + // NOTE: This method may result in data loss, so we do not implement it.
1.137 + return NS_ERROR_NOT_IMPLEMENTED;
1.138 +}
1.139 +
1.140 +/////////
1.141 +// nsIStringInputStream implementation
1.142 +/////////
1.143 +
1.144 +NS_IMETHODIMP
1.145 +nsStringInputStream::SetData(const char *data, int32_t dataLen)
1.146 +{
1.147 + if (NS_WARN_IF(!data))
1.148 + return NS_ERROR_INVALID_ARG;
1.149 + mData.Assign(data, dataLen);
1.150 + mOffset = 0;
1.151 + return NS_OK;
1.152 +}
1.153 +
1.154 +NS_IMETHODIMP
1.155 +nsStringInputStream::AdoptData(char *data, int32_t dataLen)
1.156 +{
1.157 + if (NS_WARN_IF(!data))
1.158 + return NS_ERROR_INVALID_ARG;
1.159 + mData.Adopt(data, dataLen);
1.160 + mOffset = 0;
1.161 + return NS_OK;
1.162 +}
1.163 +
1.164 +NS_IMETHODIMP
1.165 +nsStringInputStream::ShareData(const char *data, int32_t dataLen)
1.166 +{
1.167 + if (NS_WARN_IF(!data))
1.168 + return NS_ERROR_INVALID_ARG;
1.169 +
1.170 + if (dataLen < 0)
1.171 + dataLen = strlen(data);
1.172 +
1.173 + mData.Rebind(data, dataLen);
1.174 + mOffset = 0;
1.175 + return NS_OK;
1.176 +}
1.177 +
1.178 +/////////
1.179 +// nsIInputStream implementation
1.180 +/////////
1.181 +
1.182 +NS_IMETHODIMP
1.183 +nsStringInputStream::Close()
1.184 +{
1.185 + Clear();
1.186 + return NS_OK;
1.187 +}
1.188 +
1.189 +NS_IMETHODIMP
1.190 +nsStringInputStream::Available(uint64_t *aLength)
1.191 +{
1.192 + NS_ASSERTION(aLength, "null ptr");
1.193 +
1.194 + if (Closed())
1.195 + return NS_BASE_STREAM_CLOSED;
1.196 +
1.197 + *aLength = LengthRemaining();
1.198 + return NS_OK;
1.199 +}
1.200 +
1.201 +NS_IMETHODIMP
1.202 +nsStringInputStream::Read(char* aBuf, uint32_t aCount, uint32_t *aReadCount)
1.203 +{
1.204 + NS_ASSERTION(aBuf, "null ptr");
1.205 + return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount);
1.206 +}
1.207 +
1.208 +NS_IMETHODIMP
1.209 +nsStringInputStream::ReadSegments(nsWriteSegmentFun writer, void *closure,
1.210 + uint32_t aCount, uint32_t *result)
1.211 +{
1.212 + NS_ASSERTION(result, "null ptr");
1.213 + NS_ASSERTION(Length() >= mOffset, "bad stream state");
1.214 +
1.215 + if (Closed())
1.216 + return NS_BASE_STREAM_CLOSED;
1.217 +
1.218 + // We may be at end-of-file
1.219 + uint32_t maxCount = LengthRemaining();
1.220 + if (maxCount == 0) {
1.221 + *result = 0;
1.222 + return NS_OK;
1.223 + }
1.224 +
1.225 + if (aCount > maxCount)
1.226 + aCount = maxCount;
1.227 + nsresult rv = writer(this, closure, mData.BeginReading() + mOffset, 0, aCount, result);
1.228 + if (NS_SUCCEEDED(rv)) {
1.229 + NS_ASSERTION(*result <= aCount,
1.230 + "writer should not write more than we asked it to write");
1.231 + mOffset += *result;
1.232 + }
1.233 +
1.234 + // errors returned from the writer end here!
1.235 + return NS_OK;
1.236 +}
1.237 +
1.238 +NS_IMETHODIMP
1.239 +nsStringInputStream::IsNonBlocking(bool *aNonBlocking)
1.240 +{
1.241 + *aNonBlocking = true;
1.242 + return NS_OK;
1.243 +}
1.244 +
1.245 +/////////
1.246 +// nsISeekableStream implementation
1.247 +/////////
1.248 +
1.249 +NS_IMETHODIMP
1.250 +nsStringInputStream::Seek(int32_t whence, int64_t offset)
1.251 +{
1.252 + if (Closed())
1.253 + return NS_BASE_STREAM_CLOSED;
1.254 +
1.255 + // Compute new stream position. The given offset may be a negative value.
1.256 +
1.257 + int64_t newPos = offset;
1.258 + switch (whence) {
1.259 + case NS_SEEK_SET:
1.260 + break;
1.261 + case NS_SEEK_CUR:
1.262 + newPos += mOffset;
1.263 + break;
1.264 + case NS_SEEK_END:
1.265 + newPos += Length();
1.266 + break;
1.267 + default:
1.268 + NS_ERROR("invalid whence");
1.269 + return NS_ERROR_INVALID_ARG;
1.270 + }
1.271 +
1.272 + if (NS_WARN_IF(newPos < 0) || NS_WARN_IF(newPos > Length()))
1.273 + return NS_ERROR_INVALID_ARG;
1.274 +
1.275 + mOffset = (uint32_t)newPos;
1.276 + return NS_OK;
1.277 +}
1.278 +
1.279 +NS_IMETHODIMP
1.280 +nsStringInputStream::Tell(int64_t* outWhere)
1.281 +{
1.282 + if (Closed())
1.283 + return NS_BASE_STREAM_CLOSED;
1.284 +
1.285 + *outWhere = mOffset;
1.286 + return NS_OK;
1.287 +}
1.288 +
1.289 +NS_IMETHODIMP
1.290 +nsStringInputStream::SetEOF()
1.291 +{
1.292 + if (Closed())
1.293 + return NS_BASE_STREAM_CLOSED;
1.294 +
1.295 + mOffset = Length();
1.296 + return NS_OK;
1.297 +}
1.298 +
1.299 +void
1.300 +nsStringInputStream::Serialize(InputStreamParams& aParams,
1.301 + FileDescriptorArray& /* aFDs */)
1.302 +{
1.303 + StringInputStreamParams params;
1.304 + params.data() = PromiseFlatCString(mData);
1.305 + aParams = params;
1.306 +}
1.307 +
1.308 +bool
1.309 +nsStringInputStream::Deserialize(const InputStreamParams& aParams,
1.310 + const FileDescriptorArray& /* aFDs */)
1.311 +{
1.312 + if (aParams.type() != InputStreamParams::TStringInputStreamParams) {
1.313 + NS_ERROR("Received unknown parameters from the other process!");
1.314 + return false;
1.315 + }
1.316 +
1.317 + const StringInputStreamParams& params =
1.318 + aParams.get_StringInputStreamParams();
1.319 +
1.320 + if (NS_FAILED(SetData(params.data()))) {
1.321 + NS_WARNING("SetData failed!");
1.322 + return false;
1.323 + }
1.324 +
1.325 + return true;
1.326 +}
1.327 +
1.328 +nsresult
1.329 +NS_NewByteInputStream(nsIInputStream** aStreamResult,
1.330 + const char* aStringToRead, int32_t aLength,
1.331 + nsAssignmentType aAssignment)
1.332 +{
1.333 + NS_PRECONDITION(aStreamResult, "null out ptr");
1.334 +
1.335 + nsStringInputStream* stream = new nsStringInputStream();
1.336 + if (! stream)
1.337 + return NS_ERROR_OUT_OF_MEMORY;
1.338 +
1.339 + NS_ADDREF(stream);
1.340 +
1.341 + nsresult rv;
1.342 + switch (aAssignment) {
1.343 + case NS_ASSIGNMENT_COPY:
1.344 + rv = stream->SetData(aStringToRead, aLength);
1.345 + break;
1.346 + case NS_ASSIGNMENT_DEPEND:
1.347 + rv = stream->ShareData(aStringToRead, aLength);
1.348 + break;
1.349 + case NS_ASSIGNMENT_ADOPT:
1.350 + rv = stream->AdoptData(const_cast<char*>(aStringToRead), aLength);
1.351 + break;
1.352 + default:
1.353 + NS_ERROR("invalid assignment type");
1.354 + rv = NS_ERROR_INVALID_ARG;
1.355 + }
1.356 +
1.357 + if (NS_FAILED(rv)) {
1.358 + NS_RELEASE(stream);
1.359 + return rv;
1.360 + }
1.361 +
1.362 + *aStreamResult = stream;
1.363 + return NS_OK;
1.364 +}
1.365 +
1.366 +nsresult
1.367 +NS_NewStringInputStream(nsIInputStream** aStreamResult,
1.368 + const nsAString& aStringToRead)
1.369 +{
1.370 + NS_LossyConvertUTF16toASCII data(aStringToRead); // truncates high-order bytes
1.371 + return NS_NewCStringInputStream(aStreamResult, data);
1.372 +}
1.373 +
1.374 +nsresult
1.375 +NS_NewCStringInputStream(nsIInputStream** aStreamResult,
1.376 + const nsACString& aStringToRead)
1.377 +{
1.378 + NS_PRECONDITION(aStreamResult, "null out ptr");
1.379 +
1.380 + nsStringInputStream* stream = new nsStringInputStream();
1.381 + if (! stream)
1.382 + return NS_ERROR_OUT_OF_MEMORY;
1.383 +
1.384 + NS_ADDREF(stream);
1.385 +
1.386 + stream->SetData(aStringToRead);
1.387 +
1.388 + *aStreamResult = stream;
1.389 + return NS_OK;
1.390 +}
1.391 +
1.392 +// factory method for constructing a nsStringInputStream object
1.393 +nsresult
1.394 +nsStringInputStreamConstructor(nsISupports *outer, REFNSIID iid, void **result)
1.395 +{
1.396 + *result = nullptr;
1.397 +
1.398 + if (NS_WARN_IF(outer))
1.399 + return NS_ERROR_NO_AGGREGATION;
1.400 +
1.401 + nsStringInputStream *inst = new nsStringInputStream();
1.402 + if (!inst)
1.403 + return NS_ERROR_OUT_OF_MEMORY;
1.404 +
1.405 + NS_ADDREF(inst);
1.406 + nsresult rv = inst->QueryInterface(iid, result);
1.407 + NS_RELEASE(inst);
1.408 +
1.409 + return rv;
1.410 +}
