test/lint/lint-locale-dependence.py

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1#!/usr/bin/env python3

3# Distributed under the MIT software license, see the accompanying

4# file COPYING or http://www.opensource.org/licenses/mit-license.php.

5#

6# Be aware that bitcoind and bitcoin-qt differ in terms of localization: Qt

7# opts in to POSIX localization by running setlocale(LC_ALL, "") on startup,

8# whereas no such call is made in bitcoind.

9#

10# Qt runs setlocale(LC_ALL, "") on initialization. This installs the locale

11# specified by the user's LC_ALL (or LC_*) environment variable as the new

12# C locale.

13#

14# In contrast, bitcoind does not opt in to localization -- no call to

15# setlocale(LC_ALL, "") is made and the environment variables LC_* are

16# thus ignored.

17#

18# This results in situations where bitcoind is guaranteed to be running

19# with the classic locale ("C") whereas the locale of bitcoin-qt will vary

20# depending on the user's environment variables.

21#

22# An example: Assuming the environment variable LC_ALL=de_DE then the

23# call std::to_string(1.23) will return "1.230000" in bitcoind but

24# "1,230000" in bitcoin-qt.

25#

26# From the Qt documentation:

27# "On Unix/Linux Qt is configured to use the system locale settings by default.

28# This can cause a conflict when using POSIX functions, for instance, when

29# converting between data types such as floats and strings, since the notation

30# may differ between locales. To get around this problem, call the POSIX function

31# setlocale(LC_NUMERIC,"C") right after initializing QApplication, QGuiApplication

32# or QCoreApplication to reset the locale that is used for number formatting to

33# "C"-locale."

34#

35# See https://doc.qt.io/qt-5/qcoreapplication.html#locale-settings and

36# https://stackoverflow.com/a/34878283 for more details.

38import re

39import sys

41from subprocess import check_output, CalledProcessError

43from lint_ignore_dirs import SHARED_EXCLUDED_SUBTREES

46KNOWN_VIOLATIONS = [

47 "src/dbwrapper.cpp:.*vsnprintf",

48 "src/span.h:.*printf",

49 "src/test/fuzz/locale.cpp:.*setlocale",

50 "src/test/util_tests.cpp:.*strtoll",

51 "src/util/syserror.cpp:.*strerror", # Outside this function use `SysErrorString`

52]

54REGEXP_EXTERNAL_DEPENDENCIES_EXCLUSIONS = [

55 "src/tinyformat.h",

56] + SHARED_EXCLUDED_SUBTREES

58LOCALE_DEPENDENT_FUNCTIONS = [

59 "alphasort", # LC_COLLATE (via strcoll)

60 "asctime", # LC_TIME (directly)

61 "asprintf", # (via vasprintf)

62 "atof", # LC_NUMERIC (via strtod)

63 "atoi", # LC_NUMERIC (via strtol)

64 "atol", # LC_NUMERIC (via strtol)

65 "atoll", # (via strtoll)

66 "atoq",

67 "btowc", # LC_CTYPE (directly)

68 "ctime", # (via asctime or localtime)

69 "dprintf", # (via vdprintf)

70 "fgetwc",

71 "fgetws",

72 "fold_case", # boost::locale::fold_case

73 "fprintf", # (via vfprintf)

74 "fputwc",

75 "fputws",

76 "fscanf", # (via __vfscanf)

77 "fwprintf", # (via __vfwprintf)

78 "getdate", # via __getdate_r => isspace // __localtime_r

79 "getwc",

80 "getwchar",

81 "is_digit", # boost::algorithm::is_digit

82 "is_space", # boost::algorithm::is_space

83 "isalnum", # LC_CTYPE

84 "isalpha", # LC_CTYPE

85 "isblank", # LC_CTYPE

86 "iscntrl", # LC_CTYPE

87 "isctype", # LC_CTYPE

88 "isdigit", # LC_CTYPE

89 "isgraph", # LC_CTYPE

90 "islower", # LC_CTYPE

91 "isprint", # LC_CTYPE

92 "ispunct", # LC_CTYPE

93 "isspace", # LC_CTYPE

94 "isupper", # LC_CTYPE

95 "iswalnum", # LC_CTYPE

96 "iswalpha", # LC_CTYPE

97 "iswblank", # LC_CTYPE

98 "iswcntrl", # LC_CTYPE

99 "iswctype", # LC_CTYPE

100 "iswdigit", # LC_CTYPE

101 "iswgraph", # LC_CTYPE

102 "iswlower", # LC_CTYPE

103 "iswprint", # LC_CTYPE

104 "iswpunct", # LC_CTYPE

105 "iswspace", # LC_CTYPE

106 "iswupper", # LC_CTYPE

107 "iswxdigit", # LC_CTYPE

108 "isxdigit", # LC_CTYPE

109 "localeconv", # LC_NUMERIC + LC_MONETARY

110 "mblen", # LC_CTYPE

111 "mbrlen",

112 "mbrtowc",

113 "mbsinit",

114 "mbsnrtowcs",

115 "mbsrtowcs",

116 "mbstowcs", # LC_CTYPE

117 "mbtowc", # LC_CTYPE

118 "mktime",

119 "normalize", # boost::locale::normalize

120 "printf", # LC_NUMERIC

121 "putwc",

122 "putwchar",

123 "scanf", # LC_NUMERIC

124 "setlocale",

125 "snprintf",

126 "sprintf",

127 "sscanf",

128 "std::locale::global",

129 "std::to_string",

130 "stod",

131 "stof",

132 "stoi",

133 "stol",

134 "stold",

135 "stoll",

136 "stoul",

137 "stoull",

138 "strcasecmp",

139 "strcasestr",

140 "strcoll", # LC_COLLATE

141 "strerror",

142 "strfmon",

143 "strftime", # LC_TIME

144 "strncasecmp",

145 "strptime",

146 "strtod", # LC_NUMERIC

147 "strtof",

148 "strtoimax",

149 "strtol", # LC_NUMERIC

150 "strtold",

151 "strtoll",

152 "strtoq",

153 "strtoul", # LC_NUMERIC

154 "strtoull",

155 "strtoumax",

156 "strtouq",

157 "strxfrm", # LC_COLLATE

158 "swprintf",

159 "to_lower", # boost::locale::to_lower

160 "to_title", # boost::locale::to_title

161 "to_upper", # boost::locale::to_upper

162 "tolower", # LC_CTYPE

163 "toupper", # LC_CTYPE

164 "towctrans",

165 "towlower", # LC_CTYPE

166 "towupper", # LC_CTYPE

167 "trim", # boost::algorithm::trim

168 "trim_left", # boost::algorithm::trim_left

169 "trim_right", # boost::algorithm::trim_right

170 "ungetwc",

171 "vasprintf",

172 "vdprintf",

173 "versionsort",

174 "vfprintf",

175 "vfscanf",

176 "vfwprintf",

177 "vprintf",

178 "vscanf",

179 "vsnprintf",

180 "vsprintf",

181 "vsscanf",

182 "vswprintf",

183 "vwprintf",

184 "wcrtomb",

185 "wcscasecmp",

186 "wcscoll", # LC_COLLATE

187 "wcsftime", # LC_TIME

188 "wcsncasecmp",

189 "wcsnrtombs",

190 "wcsrtombs",

191 "wcstod", # LC_NUMERIC

192 "wcstof",

193 "wcstoimax",

194 "wcstol", # LC_NUMERIC

195 "wcstold",

196 "wcstoll",

197 "wcstombs", # LC_CTYPE

198 "wcstoul", # LC_NUMERIC

199 "wcstoull",

200 "wcstoumax",

201 "wcswidth",

202 "wcsxfrm", # LC_COLLATE

203 "wctob",

204 "wctomb", # LC_CTYPE

205 "wctrans",

206 "wctype",

207 "wcwidth",

208 "wprintf"

209]

210

211

212def find_locale_dependent_function_uses():

213 regexp_locale_dependent_functions = "|".join(LOCALE_DEPENDENT_FUNCTIONS)

214 exclude_args = [":(exclude)" + excl for excl in REGEXP_EXTERNAL_DEPENDENCIES_EXCLUSIONS]

215 git_grep_command = ["git", "grep", "--extended-regexp", "[^a-zA-Z0-9_\\`'\"<>](" + regexp_locale_dependent_functions + ")(_r|_s)?\\(", "--", "*.cpp", "*.h"] + exclude_args

216 git_grep_output = list()

217

218 try:

219 git_grep_output = check_output(git_grep_command, text=True).splitlines()

220 except CalledProcessError as e:

221 if e.returncode > 1:

222 raise e

223

224 return git_grep_output

225

226

227def main():

228 exit_code = 0

229

230 regexp_ignore_known_violations = "|".join(KNOWN_VIOLATIONS)

231 git_grep_output = find_locale_dependent_function_uses()

232

233 for locale_dependent_function in LOCALE_DEPENDENT_FUNCTIONS:

234 matches = [line for line in git_grep_output

235 if re.search("[^a-zA-Z0-9_\\`'\"<>]" + locale_dependent_function + "(_r|_s)?\\(", line)

236 and not re.search("\\.(c|cpp|h):\\s*//.*" + locale_dependent_function, line)

237 and not re.search(regexp_ignore_known_violations, line)]

238 if matches:

239 print(f"The locale dependent function {locale_dependent_function}(...) appears to be used:")

240 for match in matches:

241 print(match)

242 print("")

243 exit_code = 1

244

245 if exit_code == 1:

246 print("Unnecessary locale dependence can cause bugs that are very tricky to isolate and fix. Please avoid using locale-dependent functions if possible.\n")

247 print(f"Advice not applicable in this specific case? Add an exception by updating the ignore list in {sys.argv[0]}")

248

249 sys.exit(exit_code)

250