net/ftp/ftp_util.cc

   1 // Copyright (c) 2011 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/ftp/ftp_util.h"
   6
   7 #include <map>
   8 #include <vector>
   9
  10 #include "base/i18n/case_conversion.h"
  11 #include "base/i18n/char_iterator.h"
  12 #include "base/logging.h"
  13 #include "base/memory/singleton.h"
  14 #include "base/strings/string_number_conversions.h"
  15 #include "base/strings/string_piece.h"
  16 #include "base/strings/string_split.h"
  17 #include "base/strings/string_tokenizer.h"
  18 #include "base/strings/string_util.h"
  19 #include "base/strings/utf_string_conversions.h"
  20 #include "base/time/time.h"
  21 #include "third_party/icu/source/common/unicode/uchar.h"
  22 #include "third_party/icu/source/i18n/unicode/datefmt.h"
  23 #include "third_party/icu/source/i18n/unicode/dtfmtsym.h"
  24
  25 using base::ASCIIToUTF16;
  26 using base::StringPiece16;
  27
  28 // For examples of Unix<->VMS path conversions, see the unit test file. On VMS
  29 // a path looks differently depending on whether it's a file or directory.
  30
  31 namespace net {
  32
  33 // static
  34 std::string FtpUtil::UnixFilePathToVMS(const std::string& unix_path) {
  35   if (unix_path.empty())
  36     return std::string();
  37
  38   base::StringTokenizer tokenizer(unix_path, "/");
  39   std::vector<std::string> tokens;
  40   while (tokenizer.GetNext())
  41     tokens.push_back(tokenizer.token());
  42
  43   if (unix_path[0] == '/') {
  44     // It's an absolute path.
  45
  46     if (tokens.empty()) {
  47       DCHECK_EQ(1U, unix_path.length());
  48       return "[]";
  49     }
  50
  51     if (tokens.size() == 1)
  52       return unix_path.substr(1);  // Drop the leading slash.
  53
  54     std::string result(tokens[0] + ":[");
  55     if (tokens.size() == 2) {
  56       // Don't ask why, it just works that way on VMS.
  57       result.append("000000");
  58     } else {
  59       result.append(tokens[1]);
  60       for (size_t i = 2; i < tokens.size() - 1; i++)
  61         result.append("." + tokens[i]);
  62     }
  63     result.append("]" + tokens[tokens.size() - 1]);
  64     return result;
  65   }
  66
  67   if (tokens.size() == 1)
  68     return unix_path;
  69
  70   std::string result("[");
  71   for (size_t i = 0; i < tokens.size() - 1; i++)
  72     result.append("." + tokens[i]);
  73   result.append("]" + tokens[tokens.size() - 1]);
  74   return result;
  75 }
  76
  77 // static
  78 std::string FtpUtil::UnixDirectoryPathToVMS(const std::string& unix_path) {
  79   if (unix_path.empty())
  80     return std::string();
  81
  82   std::string path(unix_path);
  83
  84   if (path[path.length() - 1] != '/')
  85     path.append("/");
  86
  87   // Reuse logic from UnixFilePathToVMS by appending a fake file name to the
  88   // real path and removing it after conversion.
  89   path.append("x");
  90   path = UnixFilePathToVMS(path);
  91   return path.substr(0, path.length() - 1);
  92 }
  93
  94 // static
  95 std::string FtpUtil::VMSPathToUnix(const std::string& vms_path) {
  96   if (vms_path.empty())
  97     return ".";
  98
  99   if (vms_path[0] == '/') {
 100     // This is not really a VMS path. Most likely the server is emulating UNIX.
 101     // Return path as-is.
 102     return vms_path;
 103   }
 104
 105   if (vms_path == "[]")
 106     return "/";
 107
 108   std::string result(vms_path);
 109   if (vms_path[0] == '[') {
 110     // It's a relative path.
 111     base::ReplaceFirstSubstringAfterOffset(
 112         &result, 0, "[.", base::StringPiece());
 113   } else {
 114     // It's an absolute path.
 115     result.insert(0, "/");
 116     base::ReplaceSubstringsAfterOffset(&result, 0, ":[000000]", "/");
 117     base::ReplaceSubstringsAfterOffset(&result, 0, ":[", "/");
 118   }
 119   std::replace(result.begin(), result.end(), '.', '/');
 120   std::replace(result.begin(), result.end(), ']', '/');
 121
 122   // Make sure the result doesn't end with a slash.
 123   if (result.length() && result[result.length() - 1] == '/')
 124     result = result.substr(0, result.length() - 1);
 125
 126   return result;
 127 }
 128
 129 namespace {
 130
 131 // Lazy-initialized map of abbreviated month names.
 132 class AbbreviatedMonthsMap {
 133  public:
 134   static AbbreviatedMonthsMap* GetInstance() {
 135     return Singleton<AbbreviatedMonthsMap>::get();
 136   }
 137
 138   // Converts abbreviated month name |text| to its number (in range 1-12).
 139   // On success returns true and puts the number in |number|.
 140   bool GetMonthNumber(const base::string16& text, int* number) {
 141     // Ignore the case of the month names. The simplest way to handle that
 142     // is to make everything lowercase.
 143     base::string16 text_lower(base::i18n::ToLower(text));
 144
 145     if (map_.find(text_lower) == map_.end())
 146       return false;
 147
 148     *number = map_[text_lower];
 149     return true;
 150   }
 151
 152  private:
 153   friend struct DefaultSingletonTraits<AbbreviatedMonthsMap>;
 154
 155   // Constructor, initializes the map based on ICU data. It is much faster
 156   // to do that just once.
 157   AbbreviatedMonthsMap() {
 158     int32_t locales_count;
 159     const icu::Locale* locales =
 160         icu::DateFormat::getAvailableLocales(locales_count);
 161
 162     for (int32_t locale = 0; locale < locales_count; locale++) {
 163       UErrorCode status(U_ZERO_ERROR);
 164
 165       icu::DateFormatSymbols format_symbols(locales[locale], status);
 166
 167       // If we cannot get format symbols for some locale, it's not a fatal
 168       // error. Just try another one.
 169       if (U_FAILURE(status))
 170         continue;
 171
 172       int32_t months_count;
 173       const icu::UnicodeString* months =
 174           format_symbols.getShortMonths(months_count);
 175
 176       for (int32_t month = 0; month < months_count; month++) {
 177         base::string16 month_name(months[month].getBuffer(),
 178                             static_cast<size_t>(months[month].length()));
 179
 180         // Ignore the case of the month names. The simplest way to handle that
 181         // is to make everything lowercase.
 182         month_name = base::i18n::ToLower(month_name);
 183
 184         map_[month_name] = month + 1;
 185
 186         // Sometimes ICU returns longer strings, but in FTP listings a shorter
 187         // abbreviation is used (for example for the Russian locale). Make sure
 188         // we always have a map entry for a three-letter abbreviation.
 189         map_[month_name.substr(0, 3)] = month + 1;
 190       }
 191     }
 192
 193     // Fail loudly if the data returned by ICU is obviously incomplete.
 194     // This is intended to catch cases like http://crbug.com/177428
 195     // much earlier. Note that the issue above turned out to be non-trivial
 196     // to reproduce - crash data is much better indicator of a problem
 197     // than incomplete bug reports.
 198     CHECK_EQ(1, map_[ASCIIToUTF16("jan")]);
 199     CHECK_EQ(2, map_[ASCIIToUTF16("feb")]);
 200     CHECK_EQ(3, map_[ASCIIToUTF16("mar")]);
 201     CHECK_EQ(4, map_[ASCIIToUTF16("apr")]);
 202     CHECK_EQ(5, map_[ASCIIToUTF16("may")]);
 203     CHECK_EQ(6, map_[ASCIIToUTF16("jun")]);
 204     CHECK_EQ(7, map_[ASCIIToUTF16("jul")]);
 205     CHECK_EQ(8, map_[ASCIIToUTF16("aug")]);
 206     CHECK_EQ(9, map_[ASCIIToUTF16("sep")]);
 207     CHECK_EQ(10, map_[ASCIIToUTF16("oct")]);
 208     CHECK_EQ(11, map_[ASCIIToUTF16("nov")]);
 209     CHECK_EQ(12, map_[ASCIIToUTF16("dec")]);
 210   }
 211
 212   // Maps lowercase month names to numbers in range 1-12.
 213   std::map<base::string16, int> map_;
 214
 215   DISALLOW_COPY_AND_ASSIGN(AbbreviatedMonthsMap);
 216 };
 217
 218 }  // namespace
 219
 220 // static
 221 bool FtpUtil::AbbreviatedMonthToNumber(const base::string16& text,
 222                                        int* number) {
 223   return AbbreviatedMonthsMap::GetInstance()->GetMonthNumber(text, number);
 224 }
 225
 226 // static
 227 bool FtpUtil::LsDateListingToTime(const base::string16& month,
 228                                   const base::string16& day,
 229                                   const base::string16& rest,
 230                                   const base::Time& current_time,
 231                                   base::Time* result) {
 232   base::Time::Exploded time_exploded = { 0 };
 233
 234   if (!AbbreviatedMonthToNumber(month, &time_exploded.month)) {
 235     // Work around garbage sent by some servers in the same column
 236     // as the month. Take just last 3 characters of the string.
 237     if (month.length() < 3 ||
 238         !AbbreviatedMonthToNumber(month.substr(month.length() - 3),
 239                                   &time_exploded.month)) {
 240       return false;
 241     }
 242   }
 243
 244   if (!base::StringToInt(day, &time_exploded.day_of_month))
 245     return false;
 246   if (time_exploded.day_of_month > 31)
 247     return false;
 248
 249   if (!base::StringToInt(rest, &time_exploded.year)) {
 250     // Maybe it's time. Does it look like time? Note that it can be any of
 251     // "HH:MM", "H:MM", "HH:M" or maybe even "H:M".
 252     if (rest.length() > 5)
 253       return false;
 254
 255     size_t colon_pos = rest.find(':');
 256     if (colon_pos == base::string16::npos)
 257       return false;
 258     if (colon_pos > 2)
 259       return false;
 260
 261     if (!base::StringToInt(
 262             StringPiece16(rest.begin(), rest.begin() + colon_pos),
 263             &time_exploded.hour)) {
 264       return false;
 265     }
 266     if (!base::StringToInt(
 267             StringPiece16(rest.begin() + colon_pos + 1, rest.end()),
 268             &time_exploded.minute)) {
 269       return false;
 270     }
 271
 272     // Guess the year.
 273     base::Time::Exploded current_exploded;
 274     current_time.LocalExplode(&current_exploded);
 275
 276     // If it's not possible for the parsed date to be in the current year,
 277     // use the previous year.
 278     if (time_exploded.month > current_exploded.month ||
 279         (time_exploded.month == current_exploded.month &&
 280          time_exploded.day_of_month > current_exploded.day_of_month)) {
 281       time_exploded.year = current_exploded.year - 1;
 282     } else {
 283       time_exploded.year = current_exploded.year;
 284     }
 285   }
 286
 287   // We don't know the time zone of the listing, so just use local time.
 288   *result = base::Time::FromLocalExploded(time_exploded);
 289   return true;
 290 }
 291
 292 // static
 293 bool FtpUtil::WindowsDateListingToTime(const base::string16& date,
 294                                        const base::string16& time,
 295                                        base::Time* result) {
 296   base::Time::Exploded time_exploded = { 0 };
 297
 298   // Date should be in format MM-DD-YY[YY].
 299   std::vector<base::StringPiece16> date_parts =
 300       base::SplitStringPiece(date, base::ASCIIToUTF16("-"),
 301                              base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 302   if (date_parts.size() != 3)
 303     return false;
 304   if (!base::StringToInt(date_parts[0], &time_exploded.month))
 305     return false;
 306   if (!base::StringToInt(date_parts[1], &time_exploded.day_of_month))
 307     return false;
 308   if (!base::StringToInt(date_parts[2], &time_exploded.year))
 309     return false;
 310   if (time_exploded.year < 0)
 311     return false;
 312   // If year has only two digits then assume that 00-79 is 2000-2079,
 313   // and 80-99 is 1980-1999.
 314   if (time_exploded.year < 80)
 315     time_exploded.year += 2000;
 316   else if (time_exploded.year < 100)
 317     time_exploded.year += 1900;
 318
 319   // Time should be in format HH:MM[(AM|PM)]
 320   if (time.length() < 5)
 321     return false;
 322
 323   std::vector<base::StringPiece16> time_parts = base::SplitStringPiece(
 324       base::StringPiece16(time).substr(0, 5), base::ASCIIToUTF16(":"),
 325       base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
 326   if (time_parts.size() != 2)
 327     return false;
 328   if (!base::StringToInt(time_parts[0], &time_exploded.hour))
 329     return false;
 330   if (!base::StringToInt(time_parts[1], &time_exploded.minute))
 331     return false;
 332   if (!time_exploded.HasValidValues())
 333     return false;
 334
 335   if (time.length() > 5) {
 336     if (time.length() != 7)
 337       return false;
 338     base::string16 am_or_pm(time.substr(5, 2));
 339     if (base::EqualsASCII(am_or_pm, "PM")) {
 340       if (time_exploded.hour < 12)
 341         time_exploded.hour += 12;
 342     } else if (base::EqualsASCII(am_or_pm, "AM")) {
 343       if (time_exploded.hour == 12)
 344         time_exploded.hour = 0;
 345     } else {
 346       return false;
 347     }
 348   }
 349
 350   // We don't know the time zone of the server, so just use local time.
 351   *result = base::Time::FromLocalExploded(time_exploded);
 352   return true;
 353 }
 354
 355 // static
 356 base::string16 FtpUtil::GetStringPartAfterColumns(const base::string16& text,
 357                                                   int columns) {
 358   base::i18n::UTF16CharIterator iter(&text);
 359
 360   // TODO(jshin): Is u_isspace the right function to use here?
 361   for (int i = 0; i < columns; i++) {
 362     // Skip the leading whitespace.
 363     while (!iter.end() && u_isspace(iter.get()))
 364       iter.Advance();
 365
 366     // Skip the actual text of i-th column.
 367     while (!iter.end() && !u_isspace(iter.get()))
 368       iter.Advance();
 369   }
 370
 371   base::string16 result(text.substr(iter.array_pos()));
 372   base::TrimWhitespace(result, base::TRIM_ALL, &result);
 373   return result;
 374 }
 375
 376 }  // namespace