src/net/url_request/view_cache_helper.cc

   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.
   4
   5 #include "net/url_request/view_cache_helper.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/strings/stringprintf.h"
  10 #include "net/base/escape.h"
  11 #include "net/base/io_buffer.h"
  12 #include "net/base/net_errors.h"
  13 #include "net/disk_cache/disk_cache.h"
  14 #include "net/http/http_cache.h"
  15 #include "net/http/http_response_headers.h"
  16 #include "net/http/http_response_info.h"
  17 #include "net/url_request/url_request_context.h"
  18
  19 #define VIEW_CACHE_HEAD \
  20   "<html><meta charset=\"utf-8\">" \
  21   "<meta http-equiv=\"Content-Security-Policy\" " \
  22   "  content=\"object-src 'none'; script-src 'none' 'unsafe-eval'\">" \
  23   "<body><table>"
  24
  25 #define VIEW_CACHE_TAIL \
  26   "</table></body></html>"
  27
  28 namespace net {
  29
  30 namespace {
  31
  32 std::string FormatEntryInfo(disk_cache::Entry* entry,
  33                             const std::string& url_prefix) {
  34   std::string key = entry->GetKey();
  35   GURL url = GURL(url_prefix + key);
  36   std::string row =
  37       "<tr><td><a href=\"" + url.spec() + "\">" + EscapeForHTML(key) +
  38       "</a></td></tr>";
  39   return row;
  40 }
  41
  42 }  // namespace.
  43
  44 ViewCacheHelper::ViewCacheHelper()
  45     : context_(NULL),
  46       disk_cache_(NULL),
  47       entry_(NULL),
  48       buf_len_(0),
  49       index_(0),
  50       data_(NULL),
  51       next_state_(STATE_NONE),
  52       weak_factory_(this) {
  53 }
  54
  55 ViewCacheHelper::~ViewCacheHelper() {
  56   if (entry_)
  57     entry_->Close();
  58 }
  59
  60 int ViewCacheHelper::GetEntryInfoHTML(const std::string& key,
  61                                       const URLRequestContext* context,
  62                                       std::string* out,
  63                                       const CompletionCallback& callback) {
  64   return GetInfoHTML(key, context, std::string(), out, callback);
  65 }
  66
  67 int ViewCacheHelper::GetContentsHTML(const URLRequestContext* context,
  68                                      const std::string& url_prefix,
  69                                      std::string* out,
  70                                      const CompletionCallback& callback) {
  71   return GetInfoHTML(std::string(), context, url_prefix, out, callback);
  72 }
  73
  74 // static
  75 void ViewCacheHelper::HexDump(const char *buf, size_t buf_len,
  76                               std::string* result) {
  77   const size_t kMaxRows = 16;
  78   int offset = 0;
  79
  80   const unsigned char *p;
  81   while (buf_len) {
  82     base::StringAppendF(result, "%08x: ", offset);
  83     offset += kMaxRows;
  84
  85     p = (const unsigned char *) buf;
  86
  87     size_t i;
  88     size_t row_max = std::min(kMaxRows, buf_len);
  89
  90     // print hex codes:
  91     for (i = 0; i < row_max; ++i)
  92       base::StringAppendF(result, "%02x ", *p++);
  93     for (i = row_max; i < kMaxRows; ++i)
  94       result->append("   ");
  95     result->append(" ");
  96
  97     // print ASCII glyphs if possible:
  98     p = (const unsigned char *) buf;
  99     for (i = 0; i < row_max; ++i, ++p) {
 100       if (*p < 0x7F && *p > 0x1F) {
 101         AppendEscapedCharForHTML(*p, result);
 102       } else {
 103         result->push_back('.');
 104       }
 105     }
 106
 107     result->push_back('\n');
 108
 109     buf += row_max;
 110     buf_len -= row_max;
 111   }
 112 }
 113
 114 //-----------------------------------------------------------------------------
 115
 116 int ViewCacheHelper::GetInfoHTML(const std::string& key,
 117                                  const URLRequestContext* context,
 118                                  const std::string& url_prefix,
 119                                  std::string* out,
 120                                  const CompletionCallback& callback) {
 121   DCHECK(callback_.is_null());
 122   DCHECK(context);
 123   key_ = key;
 124   context_ = context;
 125   url_prefix_ = url_prefix;
 126   data_ = out;
 127   next_state_ = STATE_GET_BACKEND;
 128   int rv = DoLoop(OK);
 129
 130   if (rv == ERR_IO_PENDING)
 131     callback_ = callback;
 132
 133   return rv;
 134 }
 135
 136 void ViewCacheHelper::DoCallback(int rv) {
 137   DCHECK_NE(ERR_IO_PENDING, rv);
 138   DCHECK(!callback_.is_null());
 139
 140   callback_.Run(rv);
 141   callback_.Reset();
 142 }
 143
 144 void ViewCacheHelper::HandleResult(int rv) {
 145   DCHECK_NE(ERR_IO_PENDING, rv);
 146   DCHECK_NE(ERR_FAILED, rv);
 147   context_ = NULL;
 148   if (!callback_.is_null())
 149     DoCallback(rv);
 150 }
 151
 152 int ViewCacheHelper::DoLoop(int result) {
 153   DCHECK(next_state_ != STATE_NONE);
 154
 155   int rv = result;
 156   do {
 157     State state = next_state_;
 158     next_state_ = STATE_NONE;
 159     switch (state) {
 160       case STATE_GET_BACKEND:
 161         DCHECK_EQ(OK, rv);
 162         rv = DoGetBackend();
 163         break;
 164       case STATE_GET_BACKEND_COMPLETE:
 165         rv = DoGetBackendComplete(rv);
 166         break;
 167       case STATE_OPEN_NEXT_ENTRY:
 168         DCHECK_EQ(OK, rv);
 169         rv = DoOpenNextEntry();
 170         break;
 171       case STATE_OPEN_NEXT_ENTRY_COMPLETE:
 172         rv = DoOpenNextEntryComplete(rv);
 173         break;
 174       case STATE_OPEN_ENTRY:
 175         DCHECK_EQ(OK, rv);
 176         rv = DoOpenEntry();
 177         break;
 178       case STATE_OPEN_ENTRY_COMPLETE:
 179         rv = DoOpenEntryComplete(rv);
 180         break;
 181       case STATE_READ_RESPONSE:
 182         DCHECK_EQ(OK, rv);
 183         rv = DoReadResponse();
 184         break;
 185       case STATE_READ_RESPONSE_COMPLETE:
 186         rv = DoReadResponseComplete(rv);
 187         break;
 188       case STATE_READ_DATA:
 189         DCHECK_EQ(OK, rv);
 190         rv = DoReadData();
 191         break;
 192       case STATE_READ_DATA_COMPLETE:
 193         rv = DoReadDataComplete(rv);
 194         break;
 195
 196       default:
 197         NOTREACHED() << "bad state";
 198         rv = ERR_FAILED;
 199         break;
 200     }
 201   } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
 202
 203   if (rv != ERR_IO_PENDING)
 204     HandleResult(rv);
 205
 206   return rv;
 207 }
 208
 209 int ViewCacheHelper::DoGetBackend() {
 210   next_state_ = STATE_GET_BACKEND_COMPLETE;
 211
 212   if (!context_->http_transaction_factory())
 213     return ERR_FAILED;
 214
 215   HttpCache* http_cache = context_->http_transaction_factory()->GetCache();
 216   if (!http_cache)
 217     return ERR_FAILED;
 218
 219   return http_cache->GetBackend(
 220       &disk_cache_, base::Bind(&ViewCacheHelper::OnIOComplete,
 221                                base::Unretained(this)));
 222 }
 223
 224 int ViewCacheHelper::DoGetBackendComplete(int result) {
 225   if (result == ERR_FAILED) {
 226     data_->append("no disk cache");
 227     return OK;
 228   }
 229
 230   DCHECK_EQ(OK, result);
 231   if (key_.empty()) {
 232     data_->assign(VIEW_CACHE_HEAD);
 233     DCHECK(!iter_);
 234     next_state_ = STATE_OPEN_NEXT_ENTRY;
 235     return OK;
 236   }
 237
 238   next_state_ = STATE_OPEN_ENTRY;
 239   return OK;
 240 }
 241
 242 int ViewCacheHelper::DoOpenNextEntry() {
 243   next_state_ = STATE_OPEN_NEXT_ENTRY_COMPLETE;
 244   if (!iter_)
 245     iter_ = disk_cache_->CreateIterator();
 246   return
 247       iter_->OpenNextEntry(&entry_, base::Bind(&ViewCacheHelper::OnIOComplete,
 248                                                base::Unretained(this)));
 249 }
 250
 251 int ViewCacheHelper::DoOpenNextEntryComplete(int result) {
 252   if (result == ERR_FAILED) {
 253     data_->append(VIEW_CACHE_TAIL);
 254     return OK;
 255   }
 256
 257   DCHECK_EQ(OK, result);
 258   data_->append(FormatEntryInfo(entry_, url_prefix_));
 259   entry_->Close();
 260   entry_ = NULL;
 261
 262   next_state_ = STATE_OPEN_NEXT_ENTRY;
 263   return OK;
 264 }
 265
 266 int ViewCacheHelper::DoOpenEntry() {
 267   next_state_ = STATE_OPEN_ENTRY_COMPLETE;
 268   return disk_cache_->OpenEntry(
 269       key_, &entry_,
 270       base::Bind(&ViewCacheHelper::OnIOComplete, base::Unretained(this)));
 271 }
 272
 273 int ViewCacheHelper::DoOpenEntryComplete(int result) {
 274   if (result == ERR_FAILED) {
 275     data_->append("no matching cache entry for: " + EscapeForHTML(key_));
 276     return OK;
 277   }
 278
 279   data_->assign(VIEW_CACHE_HEAD);
 280   data_->append(EscapeForHTML(entry_->GetKey()));
 281   next_state_ = STATE_READ_RESPONSE;
 282   return OK;
 283 }
 284
 285 int ViewCacheHelper::DoReadResponse() {
 286   next_state_ = STATE_READ_RESPONSE_COMPLETE;
 287   buf_len_ = entry_->GetDataSize(0);
 288   if (!buf_len_)
 289     return buf_len_;
 290
 291   buf_ = new IOBuffer(buf_len_);
 292   return entry_->ReadData(
 293       0,
 294       0,
 295       buf_.get(),
 296       buf_len_,
 297       base::Bind(&ViewCacheHelper::OnIOComplete, weak_factory_.GetWeakPtr()));
 298 }
 299
 300 int ViewCacheHelper::DoReadResponseComplete(int result) {
 301   if (result && result == buf_len_) {
 302     HttpResponseInfo response;
 303     bool truncated;
 304     if (HttpCache::ParseResponseInfo(
 305             buf_->data(), buf_len_, &response, &truncated) &&
 306         response.headers.get()) {
 307       if (truncated)
 308         data_->append("<pre>RESPONSE_INFO_TRUNCATED</pre>");
 309
 310       data_->append("<hr><pre>");
 311       data_->append(EscapeForHTML(response.headers->GetStatusLine()));
 312       data_->push_back('\n');
 313
 314       void* iter = NULL;
 315       std::string name, value;
 316       while (response.headers->EnumerateHeaderLines(&iter, &name, &value)) {
 317         data_->append(EscapeForHTML(name));
 318         data_->append(": ");
 319         data_->append(EscapeForHTML(value));
 320         data_->push_back('\n');
 321       }
 322       data_->append("</pre>");
 323     }
 324   }
 325
 326   index_ = 0;
 327   next_state_ = STATE_READ_DATA;
 328   return OK;
 329 }
 330
 331 int ViewCacheHelper::DoReadData() {
 332   data_->append("<hr><pre>");
 333
 334   next_state_ = STATE_READ_DATA_COMPLETE;
 335   buf_len_ = entry_->GetDataSize(index_);
 336   if (!buf_len_)
 337     return buf_len_;
 338
 339   buf_ = new IOBuffer(buf_len_);
 340   return entry_->ReadData(
 341       index_,
 342       0,
 343       buf_.get(),
 344       buf_len_,
 345       base::Bind(&ViewCacheHelper::OnIOComplete, weak_factory_.GetWeakPtr()));
 346 }
 347
 348 int ViewCacheHelper::DoReadDataComplete(int result) {
 349   if (result && result == buf_len_) {
 350     HexDump(buf_->data(), buf_len_, data_);
 351   }
 352   data_->append("</pre>");
 353   index_++;
 354   if (index_ < HttpCache::kNumCacheEntryDataIndices) {
 355     next_state_ = STATE_READ_DATA;
 356   } else {
 357     data_->append(VIEW_CACHE_TAIL);
 358     entry_->Close();
 359     entry_ = NULL;
 360   }
 361   return OK;
 362 }
 363
 364 void ViewCacheHelper::OnIOComplete(int result) {
 365   DoLoop(result);
 366 }
 367
 368 }  // namespace net.