/Unittests/googletest/src/gtest-port.cc

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 29//
 30// Author: wan@google.com (Zhanyong Wan)
 31
 32#include <gtest/internal/gtest-port.h>
 33
 34#include <limits.h>
 35#include <stdlib.h>
 36#include <stdio.h>
 37
 38#if GTEST_OS_WINDOWS_MOBILE
 39#include <windows.h>  // For TerminateProcess()
 40#elif GTEST_OS_WINDOWS
 41#include <io.h>
 42#include <sys/stat.h>
 43#else
 44#include <unistd.h>
 45#endif  // GTEST_OS_WINDOWS_MOBILE
 46
 47#if GTEST_OS_MAC
 48#include <mach/mach_init.h>
 49#include <mach/task.h>
 50#include <mach/vm_map.h>
 51#endif  // GTEST_OS_MAC
 52
 53#include <gtest/gtest-spi.h>
 54#include <gtest/gtest-message.h>
 55#include <gtest/internal/gtest-string.h>
 56
 57// Indicates that this translation unit is part of Google Test's
 58// implementation.  It must come before gtest-internal-inl.h is
 59// included, or there will be a compiler error.  This trick is to
 60// prevent a user from accidentally including gtest-internal-inl.h in
 61// his code.
 62#define GTEST_IMPLEMENTATION_ 1
 63#include "src/gtest-internal-inl.h"
 64#undef GTEST_IMPLEMENTATION_
 65
 66namespace testing {
 67namespace internal {
 68
 69#if defined(_MSC_VER) || defined(__BORLANDC__)
 70// MSVC and C++Builder do not provide a definition of STDERR_FILENO.
 71const int kStdErrFileno = 2;
 72#else
 73const int kStdErrFileno = STDERR_FILENO;
 74#endif  // _MSC_VER
 75
 76#if GTEST_OS_MAC
 77
 78// Returns the number of threads running in the process, or 0 to indicate that
 79// we cannot detect it.
 80size_t GetThreadCount() {
 81  const task_t task = mach_task_self();
 82  mach_msg_type_number_t thread_count;
 83  thread_act_array_t thread_list;
 84  const kern_return_t status = task_threads(task, &thread_list, &thread_count);
 85  if (status == KERN_SUCCESS) {
 86    // task_threads allocates resources in thread_list and we need to free them
 87    // to avoid leaks.
 88    vm_deallocate(task,
 89                  reinterpret_cast<vm_address_t>(thread_list),
 90                  sizeof(thread_t) * thread_count);
 91    return static_cast<size_t>(thread_count);
 92  } else {
 93    return 0;
 94  }
 95}
 96
 97#else
 98
 99size_t GetThreadCount() {
100  // There's no portable way to detect the number of threads, so we just
101  // return 0 to indicate that we cannot detect it.
102  return 0;
103}
104
105#endif  // GTEST_OS_MAC
106
107#if GTEST_USES_POSIX_RE
108
109// Implements RE.  Currently only needed for death tests.
110
111RE::~RE() {
112  regfree(&partial_regex_);
113  regfree(&full_regex_);
114  free(const_cast<char*>(pattern_));
115}
116
117// Returns true iff regular expression re matches the entire str.
118bool RE::FullMatch(const char* str, const RE& re) {
119  if (!re.is_valid_) return false;
120
121  regmatch_t match;
122  return regexec(&re.full_regex_, str, 1, &match, 0) == 0;
123}
124
125// Returns true iff regular expression re matches a substring of str
126// (including str itself).
127bool RE::PartialMatch(const char* str, const RE& re) {
128  if (!re.is_valid_) return false;
129
130  regmatch_t match;
131  return regexec(&re.partial_regex_, str, 1, &match, 0) == 0;
132}
133
134// Initializes an RE from its string representation.
135void RE::Init(const char* regex) {
136  pattern_ = posix::StrDup(regex);
137
138  // Reserves enough bytes to hold the regular expression used for a
139  // full match.
140  const size_t full_regex_len = strlen(regex) + 10;
141  char* const full_pattern = new char[full_regex_len];
142
143  snprintf(full_pattern, full_regex_len, "^(%s)$", regex);
144  is_valid_ = regcomp(&full_regex_, full_pattern, REG_EXTENDED) == 0;
145  // We want to call regcomp(&partial_regex_, ...) even if the
146  // previous expression returns false.  Otherwise partial_regex_ may
147  // not be properly initialized can may cause trouble when it's
148  // freed.
149  //
150  // Some implementation of POSIX regex (e.g. on at least some
151  // versions of Cygwin) doesn't accept the empty string as a valid
152  // regex.  We change it to an equivalent form "()" to be safe.
153  const char* const partial_regex = (*regex == '\0') ? "()" : regex;
154  is_valid_ = (regcomp(&partial_regex_, partial_regex, REG_EXTENDED) == 0)
155      && is_valid_;
156  EXPECT_TRUE(is_valid_)
157      << "Regular expression \"" << regex
158      << "\" is not a valid POSIX Extended regular expression.";
159
160  delete[] full_pattern;
161}
162
163#elif GTEST_USES_SIMPLE_RE
164
165// Returns true iff ch appears anywhere in str (excluding the
166// terminating '\0' character).
167bool IsInSet(char ch, const char* str) {
168  return ch != '\0' && strchr(str, ch) != NULL;
169}
170
171// Returns true iff ch belongs to the given classification.  Unlike
172// similar functions in <ctype.h>, these aren't affected by the
173// current locale.
174bool IsDigit(char ch) { return '0' <= ch && ch <= '9'; }
175bool IsPunct(char ch) {
176  return IsInSet(ch, "^-!\"#$%&'()*+,./:;<=>?@[\\]_`{|}~");
177}
178bool IsRepeat(char ch) { return IsInSet(ch, "?*+"); }
179bool IsWhiteSpace(char ch) { return IsInSet(ch, " \f\n\r\t\v"); }
180bool IsWordChar(char ch) {
181  return ('a' <= ch && ch <= 'z') || ('A' <= ch && ch <= 'Z') ||
182      ('0' <= ch && ch <= '9') || ch == '_';
183}
184
185// Returns true iff "\\c" is a supported escape sequence.
186bool IsValidEscape(char c) {
187  return (IsPunct(c) || IsInSet(c, "dDfnrsStvwW"));
188}
189
190// Returns true iff the given atom (specified by escaped and pattern)
191// matches ch.  The result is undefined if the atom is invalid.
192bool AtomMatchesChar(bool escaped, char pattern_char, char ch) {
193  if (escaped) {  // "\\p" where p is pattern_char.
194    switch (pattern_char) {
195      case 'd': return IsDigit(ch);
196      case 'D': return !IsDigit(ch);
197      case 'f': return ch == '\f';
198      case 'n': return ch == '\n';
199      case 'r': return ch == '\r';
200      case 's': return IsWhiteSpace(ch);
201      case 'S': return !IsWhiteSpace(ch);
202      case 't': return ch == '\t';
203      case 'v': return ch == '\v';
204      case 'w': return IsWordChar(ch);
205      case 'W': return !IsWordChar(ch);
206    }
207    return IsPunct(pattern_char) && pattern_char == ch;
208  }
209
210  return (pattern_char == '.' && ch != '\n') || pattern_char == ch;
211}
212
213// Helper function used by ValidateRegex() to format error messages.
214String FormatRegexSyntaxError(const char* regex, int index) {
215  return (Message() << "Syntax error at index " << index
216          << " in simple regular expression \"" << regex << "\": ").GetString();
217}
218
219// Generates non-fatal failures and returns false if regex is invalid;
220// otherwise returns true.
221bool ValidateRegex(const char* regex) {
222  if (regex == NULL) {
223    // TODO(wan@google.com): fix the source file location in the
224    // assertion failures to match where the regex is used in user
225    // code.
226    ADD_FAILURE() << "NULL is not a valid simple regular expression.";
227    return false;
228  }
229
230  bool is_valid = true;
231
232  // True iff ?, *, or + can follow the previous atom.
233  bool prev_repeatable = false;
234  for (int i = 0; regex[i]; i++) {
235    if (regex[i] == '\\') {  // An escape sequence
236      i++;
237      if (regex[i] == '\0') {
238        ADD_FAILURE() << FormatRegexSyntaxError(regex, i - 1)
239                      << "'\\' cannot appear at the end.";
240        return false;
241      }
242
243      if (!IsValidEscape(regex[i])) {
244        ADD_FAILURE() << FormatRegexSyntaxError(regex, i - 1)
245                      << "invalid escape sequence \"\\" << regex[i] << "\".";
246        is_valid = false;
247      }
248      prev_repeatable = true;
249    } else {  // Not an escape sequence.
250      const char ch = regex[i];
251
252      if (ch == '^' && i > 0) {
253        ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
254                      << "'^' can only appear at the beginning.";
255        is_valid = false;
256      } else if (ch == '$' && regex[i + 1] != '\0') {
257        ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
258                      << "'$' can only appear at the end.";
259        is_valid = false;
260      } else if (IsInSet(ch, "()[]{}|")) {
261        ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
262                      << "'" << ch << "' is unsupported.";
263        is_valid = false;
264      } else if (IsRepeat(ch) && !prev_repeatable) {
265        ADD_FAILURE() << FormatRegexSyntaxError(regex, i)
266                      << "'" << ch << "' can only follow a repeatable token.";
267        is_valid = false;
268      }
269
270      prev_repeatable = !IsInSet(ch, "^$?*+");
271    }
272  }
273
274  return is_valid;
275}
276
277// Matches a repeated regex atom followed by a valid simple regular
278// expression.  The regex atom is defined as c if escaped is false,
279// or \c otherwise.  repeat is the repetition meta character (?, *,
280// or +).  The behavior is undefined if str contains too many
281// characters to be indexable by size_t, in which case the test will
282// probably time out anyway.  We are fine with this limitation as
283// std::string has it too.
284bool MatchRepetitionAndRegexAtHead(
285    bool escaped, char c, char repeat, const char* regex,
286    const char* str) {
287  const size_t min_count = (repeat == '+') ? 1 : 0;
288  const size_t max_count = (repeat == '?') ? 1 :
289      static_cast<size_t>(-1) - 1;
290  // We cannot call numeric_limits::max() as it conflicts with the
291  // max() macro on Windows.
292
293  for (size_t i = 0; i <= max_count; ++i) {
294    // We know that the atom matches each of the first i characters in str.
295    if (i >= min_count && MatchRegexAtHead(regex, str + i)) {
296      // We have enough matches at the head, and the tail matches too.
297      // Since we only care about *whether* the pattern matches str
298      // (as opposed to *how* it matches), there is no need to find a
299      // greedy match.
300      return true;
301    }
302    if (str[i] == '\0' || !AtomMatchesChar(escaped, c, str[i]))
303      return false;
304  }
305  return false;
306}
307
308// Returns true iff regex matches a prefix of str.  regex must be a
309// valid simple regular expression and not start with "^", or the
310// result is undefined.
311bool MatchRegexAtHead(const char* regex, const char* str) {
312  if (*regex == '\0')  // An empty regex matches a prefix of anything.
313    return true;
314
315  // "$" only matches the end of a string.  Note that regex being
316  // valid guarantees that there's nothing after "$" in it.
317  if (*regex == '$')
318    return *str == '\0';
319
320  // Is the first thing in regex an escape sequence?
321  const bool escaped = *regex == '\\';
322  if (escaped)
323    ++regex;
324  if (IsRepeat(regex[1])) {
325    // MatchRepetitionAndRegexAtHead() calls MatchRegexAtHead(), so
326    // here's an indirect recursion.  It terminates as the regex gets
327    // shorter in each recursion.
328    return MatchRepetitionAndRegexAtHead(
329        escaped, regex[0], regex[1], regex + 2, str);
330  } else {
331    // regex isn't empty, isn't "$", and doesn't start with a
332    // repetition.  We match the first atom of regex with the first
333    // character of str and recurse.
334    return (*str != '\0') && AtomMatchesChar(escaped, *regex, *str) &&
335        MatchRegexAtHead(regex + 1, str + 1);
336  }
337}
338
339// Returns true iff regex matches any substring of str.  regex must be
340// a valid simple regular expression, or the result is undefined.
341//
342// The algorithm is recursive, but the recursion depth doesn't exceed
343// the regex length, so we won't need to worry about running out of
344// stack space normally.  In rare cases the time complexity can be
345// exponential with respect to the regex length + the string length,
346// but usually it's must faster (often close to linear).
347bool MatchRegexAnywhere(const char* regex, const char* str) {
348  if (regex == NULL || str == NULL)
349    return false;
350
351  if (*regex == '^')
352    return MatchRegexAtHead(regex + 1, str);
353
354  // A successful match can be anywhere in str.
355  do {
356    if (MatchRegexAtHead(regex, str))
357      return true;
358  } while (*str++ != '\0');
359  return false;
360}
361
362// Implements the RE class.
363
364RE::~RE() {
365  free(const_cast<char*>(pattern_));
366  free(const_cast<char*>(full_pattern_));
367}
368
369// Returns true iff regular expression re matches the entire str.
370bool RE::FullMatch(const char* str, const RE& re) {
371  return re.is_valid_ && MatchRegexAnywhere(re.full_pattern_, str);
372}
373
374// Returns true iff regular expression re matches a substring of str
375// (including str itself).
376bool RE::PartialMatch(const char* str, const RE& re) {
377  return re.is_valid_ && MatchRegexAnywhere(re.pattern_, str);
378}
379
380// Initializes an RE from its string representation.
381void RE::Init(const char* regex) {
382  pattern_ = full_pattern_ = NULL;
383  if (regex != NULL) {
384    pattern_ = posix::StrDup(regex);
385  }
386
387  is_valid_ = ValidateRegex(regex);
388  if (!is_valid_) {
389    // No need to calculate the full pattern when the regex is invalid.
390    return;
391  }
392
393  const size_t len = strlen(regex);
394  // Reserves enough bytes to hold the regular expression used for a
395  // full match: we need space to prepend a '^', append a '$', and
396  // terminate the string with '\0'.
397  char* buffer = static_cast<char*>(malloc(len + 3));
398  full_pattern_ = buffer;
399
400  if (*regex != '^')
401    *buffer++ = '^';  // Makes sure full_pattern_ starts with '^'.
402
403  // We don't use snprintf or strncpy, as they trigger a warning when
404  // compiled with VC++ 8.0.
405  memcpy(buffer, regex, len);
406  buffer += len;
407
408  if (len == 0 || regex[len - 1] != '$')
409    *buffer++ = '$';  // Makes sure full_pattern_ ends with '$'.
410
411  *buffer = '\0';
412}
413
414#endif  // GTEST_USES_POSIX_RE
415
416
417GTestLog::GTestLog(GTestLogSeverity severity, const char* file, int line)
418    : severity_(severity) {
419  const char* const marker =
420      severity == GTEST_INFO ?    "[  INFO ]" :
421      severity == GTEST_WARNING ? "[WARNING]" :
422      severity == GTEST_ERROR ?   "[ ERROR ]" : "[ FATAL ]";
423  GetStream() << ::std::endl << marker << " "
424              << FormatFileLocation(file, line).c_str() << ": ";
425}
426
427// Flushes the buffers and, if severity is GTEST_FATAL, aborts the program.
428GTestLog::~GTestLog() {
429  GetStream() << ::std::endl;
430  if (severity_ == GTEST_FATAL) {
431    fflush(stderr);
432    posix::Abort();
433  }
434}
435// Disable Microsoft deprecation warnings for POSIX functions called from
436// this class (creat, dup, dup2, and close)
437#ifdef _MSC_VER
438#pragma warning(push)
439#pragma warning(disable: 4996)
440#endif  // _MSC_VER
441
442// Defines the stderr capturer.
443
444class CapturedStderr {
445 public:
446  // The ctor redirects stderr to a temporary file.
447  CapturedStderr() {
448#if GTEST_OS_WINDOWS_MOBILE
449    // Not supported on Windows CE.
450    posix::Abort();
451#else
452    uncaptured_fd_ = dup(kStdErrFileno);
453
454#if GTEST_OS_WINDOWS
455    char temp_dir_path[MAX_PATH + 1] = { '\0' };  // NOLINT
456    char temp_file_path[MAX_PATH + 1] = { '\0' };  // NOLINT
457
458    ::GetTempPathA(sizeof(temp_dir_path), temp_dir_path);
459    ::GetTempFileNameA(temp_dir_path, "gtest_redir", 0, temp_file_path);
460    const int captured_fd = creat(temp_file_path, _S_IREAD | _S_IWRITE);
461    filename_ = temp_file_path;
462#else
463    // There's no guarantee that a test has write access to the
464    // current directory, so we create the temporary file in the /tmp
465    // directory instead.
466    char name_template[] = "/tmp/captured_stderr.XXXXXX";
467    const int captured_fd = mkstemp(name_template);
468    filename_ = name_template;
469#endif  // GTEST_OS_WINDOWS
470    fflush(NULL);
471    dup2(captured_fd, kStdErrFileno);
472    close(captured_fd);
473#endif  // GTEST_OS_WINDOWS_MOBILE
474  }
475
476  ~CapturedStderr() {
477#if !GTEST_OS_WINDOWS_MOBILE
478    remove(filename_.c_str());
479#endif  // !GTEST_OS_WINDOWS_MOBILE
480  }
481
482  // Stops redirecting stderr.
483  void StopCapture() {
484#if !GTEST_OS_WINDOWS_MOBILE
485    // Restores the original stream.
486    fflush(NULL);
487    dup2(uncaptured_fd_, kStdErrFileno);
488    close(uncaptured_fd_);
489    uncaptured_fd_ = -1;
490#endif  // !GTEST_OS_WINDOWS_MOBILE
491  }
492
493  // Returns the name of the temporary file holding the stderr output.
494  // GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we
495  // can use it here.
496  ::std::string filename() const { return filename_; }
497
498 private:
499  int uncaptured_fd_;
500  ::std::string filename_;
501};
502
503#ifdef _MSC_VER
504#pragma warning(pop)
505#endif  // _MSC_VER
506
507static CapturedStderr* g_captured_stderr = NULL;
508
509// Returns the size (in bytes) of a file.
510static size_t GetFileSize(FILE * file) {
511  fseek(file, 0, SEEK_END);
512  return static_cast<size_t>(ftell(file));
513}
514
515// Reads the entire content of a file as a string.
516static String ReadEntireFile(FILE * file) {
517  const size_t file_size = GetFileSize(file);
518  char* const buffer = new char[file_size];
519
520  size_t bytes_last_read = 0;  // # of bytes read in the last fread()
521  size_t bytes_read = 0;       // # of bytes read so far
522
523  fseek(file, 0, SEEK_SET);
524
525  // Keeps reading the file until we cannot read further or the
526  // pre-determined file size is reached.
527  do {
528    bytes_last_read = fread(buffer+bytes_read, 1, file_size-bytes_read, file);
529    bytes_read += bytes_last_read;
530  } while (bytes_last_read > 0 && bytes_read < file_size);
531
532  const String content(buffer, bytes_read);
533  delete[] buffer;
534
535  return content;
536}
537
538// Starts capturing stderr.
539void CaptureStderr() {
540  if (g_captured_stderr != NULL) {
541    GTEST_LOG_(FATAL) << "Only one stderr capturer can exist at one time.";
542  }
543  g_captured_stderr = new CapturedStderr;
544}
545
546// Stops capturing stderr and returns the captured string.
547// GTEST_HAS_DEATH_TEST implies that we have ::std::string, so we can
548// use it here.
549String GetCapturedStderr() {
550  g_captured_stderr->StopCapture();
551
552  FILE* const file = posix::FOpen(g_captured_stderr->filename().c_str(), "r");
553  const String content = ReadEntireFile(file);
554  posix::FClose(file);
555
556  delete g_captured_stderr;
557  g_captured_stderr = NULL;
558
559  return content;
560}
561
562#if GTEST_HAS_DEATH_TEST
563
564// A copy of all command line arguments.  Set by InitGoogleTest().
565::std::vector<String> g_argvs;
566
567// Returns the command line as a vector of strings.
568const ::std::vector<String>& GetArgvs() { return g_argvs; }
569
570#endif  // GTEST_HAS_DEATH_TEST
571
572#if GTEST_OS_WINDOWS_MOBILE
573namespace posix {
574void Abort() {
575  DebugBreak();
576  TerminateProcess(GetCurrentProcess(), 1);
577}
578}  // namespace posix
579#endif  // GTEST_OS_WINDOWS_MOBILE
580
581// Returns the name of the environment variable corresponding to the
582// given flag.  For example, FlagToEnvVar("foo") will return
583// "GTEST_FOO" in the open-source version.
584static String FlagToEnvVar(const char* flag) {
585  const String full_flag =
586      (Message() << GTEST_FLAG_PREFIX_ << flag).GetString();
587
588  Message env_var;
589  for (size_t i = 0; i != full_flag.length(); i++) {
590    env_var << static_cast<char>(toupper(full_flag.c_str()[i]));
591  }
592
593  return env_var.GetString();
594}
595
596// Parses 'str' for a 32-bit signed integer.  If successful, writes
597// the result to *value and returns true; otherwise leaves *value
598// unchanged and returns false.
599bool ParseInt32(const Message& src_text, const char* str, Int32* value) {
600  // Parses the environment variable as a decimal integer.
601  char* end = NULL;
602  const long long_value = strtol(str, &end, 10);  // NOLINT
603
604  // Has strtol() consumed all characters in the string?
605  if (*end != '\0') {
606    // No - an invalid character was encountered.
607    Message msg;
608    msg << "WARNING: " << src_text
609        << " is expected to be a 32-bit integer, but actually"
610        << " has value \"" << str << "\".\n";
611    printf("%s", msg.GetString().c_str());
612    fflush(stdout);
613    return false;
614  }
615
616  // Is the parsed value in the range of an Int32?
617  const Int32 result = static_cast<Int32>(long_value);
618  if (long_value == LONG_MAX || long_value == LONG_MIN ||
619      // The parsed value overflows as a long.  (strtol() returns
620      // LONG_MAX or LONG_MIN when the input overflows.)
621      result != long_value
622      // The parsed value overflows as an Int32.
623      ) {
624    Message msg;
625    msg << "WARNING: " << src_text
626        << " is expected to be a 32-bit integer, but actually"
627        << " has value " << str << ", which overflows.\n";
628    printf("%s", msg.GetString().c_str());
629    fflush(stdout);
630    return false;
631  }
632
633  *value = result;
634  return true;
635}
636
637// Reads and returns the Boolean environment variable corresponding to
638// the given flag; if it's not set, returns default_value.
639//
640// The value is considered true iff it's not "0".
641bool BoolFromGTestEnv(const char* flag, bool default_value) {
642  const String env_var = FlagToEnvVar(flag);
643  const char* const string_value = posix::GetEnv(env_var.c_str());
644  return string_value == NULL ?
645      default_value : strcmp(string_value, "0") != 0;
646}
647
648// Reads and returns a 32-bit integer stored in the environment
649// variable corresponding to the given flag; if it isn't set or
650// doesn't represent a valid 32-bit integer, returns default_value.
651Int32 Int32FromGTestEnv(const char* flag, Int32 default_value) {
652  const String env_var = FlagToEnvVar(flag);
653  const char* const string_value = posix::GetEnv(env_var.c_str());
654  if (string_value == NULL) {
655    // The environment variable is not set.
656    return default_value;
657  }
658
659  Int32 result = default_value;
660  if (!ParseInt32(Message() << "Environment variable " << env_var,
661                  string_value, &result)) {
662    printf("The default value %s is used.\n",
663           (Message() << default_value).GetString().c_str());
664    fflush(stdout);
665    return default_value;
666  }
667
668  return result;
669}
670
671// Reads and returns the string environment variable corresponding to
672// the given flag; if it's not set, returns default_value.
673const char* StringFromGTestEnv(const char* flag, const char* default_value) {
674  const String env_var = FlagToEnvVar(flag);
675  const char* const value = posix::GetEnv(env_var.c_str());
676  return value == NULL ? default_value : value;
677}
678
679}  // namespace internal
680}  // namespace testing