summaryrefslogtreecommitdiffstats
path: root/Source/cmTimestamp.cxx
blob: 2a70ed04ced90076a19c62af9a3a30e1ce009716 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
/*============================================================================
  CMake - Cross Platform Makefile Generator
  Copyright 2012 Kitware, Inc., Insight Software Consortium

  Distributed under the OSI-approved BSD License (the "License");
  see accompanying file Copyright.txt for details.

  This software is distributed WITHOUT ANY WARRANTY; without even the
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the License for more information.
============================================================================*/
#include "cmTimestamp.h"

#include <cstdlib>
#include <cstring>
#include <sstream>

#include <sys/types.h>
// include sys/stat.h after sys/types.h
#include <sys/stat.h>

std::string cmTimestamp::CurrentTime(const std::string& formatString,
                                     bool utcFlag)
{
  time_t currentTimeT = time(0);
  if (currentTimeT == time_t(-1)) {
    return std::string();
  }

  return CreateTimestampFromTimeT(currentTimeT, formatString, utcFlag);
}

std::string cmTimestamp::FileModificationTime(const char* path,
                                              const std::string& formatString,
                                              bool utcFlag)
{
  if (!cmsys::SystemTools::FileExists(path)) {
    return std::string();
  }

  time_t mtime = cmsys::SystemTools::ModifiedTime(path);
  return CreateTimestampFromTimeT(mtime, formatString, utcFlag);
}

std::string cmTimestamp::CreateTimestampFromTimeT(time_t timeT,
                                                  std::string formatString,
                                                  bool utcFlag) const
{
  if (formatString.empty()) {
    formatString = "%Y-%m-%dT%H:%M:%S";
    if (utcFlag) {
      formatString += "Z";
    }
  }

  struct tm timeStruct;
  memset(&timeStruct, 0, sizeof(timeStruct));

  struct tm* ptr = (struct tm*)0;
  if (utcFlag) {
    ptr = gmtime(&timeT);
  } else {
    ptr = localtime(&timeT);
  }

  if (ptr == 0) {
    return std::string();
  }

  timeStruct = *ptr;

  std::string result;
  for (std::string::size_type i = 0; i < formatString.size(); ++i) {
    char c1 = formatString[i];
    char c2 = (i + 1 < formatString.size()) ? formatString[i + 1]
                                            : static_cast<char>(0);

    if (c1 == '%' && c2 != 0) {
      result += AddTimestampComponent(c2, timeStruct, timeT);
      ++i;
    } else {
      result += c1;
    }
  }

  return result;
}

time_t cmTimestamp::CreateUtcTimeTFromTm(struct tm& tm) const
{
#if defined(_MSC_VER) && _MSC_VER >= 1400
  return _mkgmtime(&tm);
#else
  // From Linux timegm() manpage.

  std::string tz_old = "TZ=";
  if (const char* tz = cmSystemTools::GetEnv("TZ")) {
    tz_old += tz;
  }

  // The standard says that "TZ=" or "TZ=[UNRECOGNIZED_TZ]" means UTC.
  // It seems that "TZ=" does NOT work, at least under Windows
  // with neither MSVC nor MinGW, so let's use explicit "TZ=UTC"

  cmSystemTools::PutEnv("TZ=UTC");

  tzset();

  time_t result = mktime(&tm);

  cmSystemTools::PutEnv(tz_old);

  tzset();

  return result;
#endif
}

std::string cmTimestamp::AddTimestampComponent(char flag,
                                               struct tm& timeStruct,
                                               const time_t timeT) const
{
  std::string formatString = "%";
  formatString += flag;

  switch (flag) {
    case 'd':
    case 'H':
    case 'I':
    case 'j':
    case 'm':
    case 'M':
    case 'S':
    case 'U':
    case 'w':
    case 'y':
    case 'Y':
      break;
    case 's': // Seconds since UNIX epoch (midnight 1-jan-1970)
    {
      // Build a time_t for UNIX epoch and substract from the input "timeT":
      struct tm tmUnixEpoch;
      memset(&tmUnixEpoch, 0, sizeof(tmUnixEpoch));
      tmUnixEpoch.tm_mday = 1;
      tmUnixEpoch.tm_year = 1970 - 1900;

      const time_t unixEpoch = this->CreateUtcTimeTFromTm(tmUnixEpoch);
      if (unixEpoch == -1) {
        cmSystemTools::Error(
          "Error generating UNIX epoch in "
          "STRING(TIMESTAMP ...). Please, file a bug report aginst CMake");
        return std::string();
      }

      std::ostringstream ss;
      ss << static_cast<long int>(difftime(timeT, unixEpoch));
      return ss.str();
    }
    default: {
      return formatString;
    }
  }

  char buffer[16];

  size_t size =
    strftime(buffer, sizeof(buffer), formatString.c_str(), &timeStruct);

  return std::string(buffer, size);
}