1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "net/http/partial_data.h"
8 #include "base/bind_helpers.h"
9 #include "base/format_macros.h"
10 #include "base/logging.h"
11 #include "base/strings/string_number_conversions.h"
12 #include "base/strings/string_util.h"
13 #include "base/strings/stringprintf.h"
14 #include "net/base/net_errors.h"
15 #include "net/disk_cache/disk_cache.h"
16 #include "net/http/http_response_headers.h"
17 #include "net/http/http_util.h"
23 // The headers that we have to process.
24 const char kLengthHeader[] = "Content-Length";
25 const char kRangeHeader[] = "Content-Range";
26 const int kDataStream = 1;
28 void AddRangeHeader(int64 start, int64 end, HttpRequestHeaders* headers) {
29 DCHECK(start >= 0 || end >= 0);
30 std::string my_start, my_end;
32 my_start = base::Int64ToString(start);
34 my_end = base::Int64ToString(end);
37 HttpRequestHeaders::kRange,
38 base::StringPrintf("bytes=%s-%s", my_start.c_str(), my_end.c_str()));
43 // A core object that can be detached from the Partialdata object at destruction
44 // so that asynchronous operations cleanup can be performed.
45 class PartialData::Core {
47 // Build a new core object. Lifetime management is automatic.
48 static Core* CreateCore(PartialData* owner) {
49 return new Core(owner);
52 // Wrapper for Entry::GetAvailableRange. If this method returns ERR_IO_PENDING
53 // PartialData::GetAvailableRangeCompleted() will be invoked on the owner
54 // object when finished (unless Cancel() is called first).
55 int GetAvailableRange(disk_cache::Entry* entry, int64 offset, int len,
58 // Cancels a pending operation. It is a mistake to call this method if there
59 // is no operation in progress; in fact, there will be no object to do so.
63 explicit Core(PartialData* owner);
66 // Pending io completion routine.
67 void OnIOComplete(int result);
72 DISALLOW_COPY_AND_ASSIGN(Core);
75 PartialData::Core::Core(PartialData* owner)
76 : owner_(owner), start_(0) {
77 DCHECK(!owner_->core_);
81 PartialData::Core::~Core() {
86 void PartialData::Core::Cancel() {
91 int PartialData::Core::GetAvailableRange(disk_cache::Entry* entry, int64 offset,
92 int len, int64* start) {
93 int rv = entry->GetAvailableRange(
94 offset, len, &start_, base::Bind(&PartialData::Core::OnIOComplete,
95 base::Unretained(this)));
96 if (rv != net::ERR_IO_PENDING) {
97 // The callback will not be invoked. Lets cleanup.
104 void PartialData::Core::OnIOComplete(int result) {
106 owner_->GetAvailableRangeCompleted(result, start_);
110 // -----------------------------------------------------------------------------
112 PartialData::PartialData()
113 : range_present_(false),
117 initial_validation_(false),
121 PartialData::~PartialData() {
126 bool PartialData::Init(const HttpRequestHeaders& headers) {
127 std::string range_header;
128 if (!headers.GetHeader(HttpRequestHeaders::kRange, &range_header))
131 std::vector<HttpByteRange> ranges;
132 if (!HttpUtil::ParseRangeHeader(range_header, &ranges) || ranges.size() != 1)
135 // We can handle this range request.
136 byte_range_ = ranges[0];
137 if (!byte_range_.IsValid())
141 current_range_start_ = byte_range_.first_byte_position();
143 DVLOG(1) << "Range start: " << current_range_start_ << " end: " <<
144 byte_range_.last_byte_position();
148 void PartialData::SetHeaders(const HttpRequestHeaders& headers) {
149 DCHECK(extra_headers_.IsEmpty());
150 extra_headers_.CopyFrom(headers);
153 void PartialData::RestoreHeaders(HttpRequestHeaders* headers) const {
154 DCHECK(current_range_start_ >= 0 || byte_range_.IsSuffixByteRange());
155 int64 end = byte_range_.IsSuffixByteRange() ?
156 byte_range_.suffix_length() : byte_range_.last_byte_position();
158 headers->CopyFrom(extra_headers_);
159 if (!truncated_ && byte_range_.IsValid())
160 AddRangeHeader(current_range_start_, end, headers);
163 int PartialData::ShouldValidateCache(disk_cache::Entry* entry,
164 const CompletionCallback& callback) {
165 DCHECK_GE(current_range_start_, 0);
167 // Scan the disk cache for the first cached portion within this range.
168 int len = GetNextRangeLen();
172 DVLOG(3) << "ShouldValidateCache len: " << len;
175 DCHECK(callback_.is_null());
176 Core* core = Core::CreateCore(this);
177 cached_min_len_ = core->GetAvailableRange(entry, current_range_start_, len,
180 if (cached_min_len_ == ERR_IO_PENDING) {
181 callback_ = callback;
182 return ERR_IO_PENDING;
184 } else if (!truncated_) {
185 if (byte_range_.HasFirstBytePosition() &&
186 byte_range_.first_byte_position() >= resource_size_) {
187 // The caller should take care of this condition because we should have
188 // failed IsRequestedRangeOK(), but it's better to be consistent here.
191 cached_min_len_ = len;
192 cached_start_ = current_range_start_;
195 if (cached_min_len_ < 0)
196 return cached_min_len_;
198 // Return a positive number to indicate success (versus error or finished).
202 void PartialData::PrepareCacheValidation(disk_cache::Entry* entry,
203 HttpRequestHeaders* headers) {
204 DCHECK_GE(current_range_start_, 0);
205 DCHECK_GE(cached_min_len_, 0);
207 int len = GetNextRangeLen();
209 range_present_ = false;
211 headers->CopyFrom(extra_headers_);
213 if (!cached_min_len_) {
214 // We don't have anything else stored.
217 byte_range_.HasLastBytePosition() ? current_range_start_ + len : 0;
220 if (current_range_start_ == cached_start_) {
221 // The data lives in the cache.
222 range_present_ = true;
223 if (len == cached_min_len_)
225 AddRangeHeader(current_range_start_, cached_start_ + cached_min_len_ - 1,
228 // This range is not in the cache.
229 AddRangeHeader(current_range_start_, cached_start_ - 1, headers);
233 bool PartialData::IsCurrentRangeCached() const {
234 return range_present_;
237 bool PartialData::IsLastRange() const {
241 bool PartialData::UpdateFromStoredHeaders(const HttpResponseHeaders* headers,
242 disk_cache::Entry* entry,
246 DCHECK_EQ(headers->response_code(), 200);
247 // We don't have the real length and the user may be trying to create a
248 // sparse entry so let's not write to this entry.
249 if (byte_range_.IsValid())
252 if (!headers->HasStrongValidators())
255 // Now we avoid resume if there is no content length, but that was not
256 // always the case so double check here.
257 int64 total_length = headers->GetContentLength();
258 if (total_length <= 0)
262 initial_validation_ = true;
263 sparse_entry_ = false;
264 int current_len = entry->GetDataSize(kDataStream);
265 byte_range_.set_first_byte_position(current_len);
266 resource_size_ = total_length;
267 current_range_start_ = current_len;
268 cached_min_len_ = current_len;
269 cached_start_ = current_len + 1;
273 if (headers->response_code() != 206) {
274 DCHECK(byte_range_.IsValid());
275 sparse_entry_ = false;
276 resource_size_ = entry->GetDataSize(kDataStream);
277 DVLOG(2) << "UpdateFromStoredHeaders size: " << resource_size_;
281 if (!headers->HasStrongValidators())
284 int64 length_value = headers->GetContentLength();
285 if (length_value <= 0)
286 return false; // We must have stored the resource length.
288 resource_size_ = length_value;
290 // Make sure that this is really a sparse entry.
291 return entry->CouldBeSparse();
294 void PartialData::SetRangeToStartDownload() {
296 DCHECK(!sparse_entry_);
297 current_range_start_ = 0;
299 initial_validation_ = false;
302 bool PartialData::IsRequestedRangeOK() {
303 if (byte_range_.IsValid()) {
304 if (!byte_range_.ComputeBounds(resource_size_))
309 if (current_range_start_ < 0)
310 current_range_start_ = byte_range_.first_byte_position();
312 // This is not a range request but we have partial data stored.
313 current_range_start_ = 0;
314 byte_range_.set_last_byte_position(resource_size_ - 1);
317 bool rv = current_range_start_ >= 0;
319 current_range_start_ = 0;
324 bool PartialData::ResponseHeadersOK(const HttpResponseHeaders* headers) {
325 if (headers->response_code() == 304) {
326 if (!byte_range_.IsValid() || truncated_)
329 // We must have a complete range here.
330 return byte_range_.HasFirstBytePosition() &&
331 byte_range_.HasLastBytePosition();
334 int64 start, end, total_length;
335 if (!headers->GetContentRange(&start, &end, &total_length))
337 if (total_length <= 0)
340 DCHECK_EQ(headers->response_code(), 206);
342 // A server should return a valid content length with a 206 (per the standard)
343 // but relax the requirement because some servers don't do that.
344 int64 content_length = headers->GetContentLength();
345 if (content_length > 0 && content_length != end - start + 1)
348 if (!resource_size_) {
349 // First response. Update our values with the ones provided by the server.
350 resource_size_ = total_length;
351 if (!byte_range_.HasFirstBytePosition()) {
352 byte_range_.set_first_byte_position(start);
353 current_range_start_ = start;
355 if (!byte_range_.HasLastBytePosition())
356 byte_range_.set_last_byte_position(end);
357 } else if (resource_size_ != total_length) {
362 if (!byte_range_.HasLastBytePosition())
363 byte_range_.set_last_byte_position(end);
366 if (start != current_range_start_)
369 if (byte_range_.IsValid() && end > byte_range_.last_byte_position())
375 // We are making multiple requests to complete the range requested by the user.
376 // Just assume that everything is fine and say that we are returning what was
378 void PartialData::FixResponseHeaders(HttpResponseHeaders* headers,
383 headers->RemoveHeader(kLengthHeader);
384 headers->RemoveHeader(kRangeHeader);
386 int64 range_len, start, end;
387 if (byte_range_.IsValid()) {
390 headers->ReplaceStatusLine("HTTP/1.1 206 Partial Content");
392 DCHECK(byte_range_.HasFirstBytePosition());
393 DCHECK(byte_range_.HasLastBytePosition());
394 start = byte_range_.first_byte_position();
395 end = byte_range_.last_byte_position();
396 range_len = end - start + 1;
398 headers->ReplaceStatusLine(
399 "HTTP/1.1 416 Requested Range Not Satisfiable");
406 base::StringPrintf("%s: bytes %" PRId64 "-%" PRId64 "/%" PRId64,
407 kRangeHeader, start, end, resource_size_));
409 // TODO(rvargas): Is it safe to change the protocol version?
410 headers->ReplaceStatusLine("HTTP/1.1 200 OK");
411 DCHECK_NE(resource_size_, 0);
412 range_len = resource_size_;
415 headers->AddHeader(base::StringPrintf("%s: %" PRId64, kLengthHeader,
419 void PartialData::FixContentLength(HttpResponseHeaders* headers) {
420 headers->RemoveHeader(kLengthHeader);
421 headers->AddHeader(base::StringPrintf("%s: %" PRId64, kLengthHeader,
425 int PartialData::CacheRead(
426 disk_cache::Entry* entry, IOBuffer* data, int data_len,
427 const net::CompletionCallback& callback) {
428 int read_len = std::min(data_len, cached_min_len_);
434 rv = entry->ReadSparseData(current_range_start_, data, read_len,
437 if (current_range_start_ > kint32max)
438 return ERR_INVALID_ARGUMENT;
440 rv = entry->ReadData(kDataStream, static_cast<int>(current_range_start_),
441 data, read_len, callback);
446 int PartialData::CacheWrite(
447 disk_cache::Entry* entry, IOBuffer* data, int data_len,
448 const net::CompletionCallback& callback) {
449 DVLOG(3) << "To write: " << data_len;
451 return entry->WriteSparseData(
452 current_range_start_, data, data_len, callback);
454 if (current_range_start_ > kint32max)
455 return ERR_INVALID_ARGUMENT;
457 return entry->WriteData(kDataStream, static_cast<int>(current_range_start_),
458 data, data_len, callback, true);
462 void PartialData::OnCacheReadCompleted(int result) {
463 DVLOG(3) << "Read: " << result;
465 current_range_start_ += result;
466 cached_min_len_ -= result;
467 DCHECK_GE(cached_min_len_, 0);
471 void PartialData::OnNetworkReadCompleted(int result) {
473 current_range_start_ += result;
476 int PartialData::GetNextRangeLen() {
478 byte_range_.HasLastBytePosition() ?
479 byte_range_.last_byte_position() - current_range_start_ + 1 :
481 if (range_len > kint32max)
482 range_len = kint32max;
483 return static_cast<int32>(range_len);
486 void PartialData::GetAvailableRangeCompleted(int result, int64 start) {
487 DCHECK(!callback_.is_null());
488 DCHECK_NE(ERR_IO_PENDING, result);
490 cached_start_ = start;
491 cached_min_len_ = result;
493 result = 1; // Return success, go ahead and validate the entry.
495 CompletionCallback cb = callback_;