var

CMakeLists.txt

@@ -7,6 +7,9 @@ project(
   LANGUAGES CXX
 )
 
+# Enable clang-tidy option
+option(ENABLE_CLANG_TIDY "Enable clang-tidy checks" OFF)
+
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED On)
 set(CMAKE_CXX_EXTENSIONS Off)
@@ -26,6 +29,23 @@ add_compile_definitions(
   $<$<CONFIG:Debug>:DEBUG>
 )
 
+# clang-tidy (targets that follow will be checked)
+if(ENABLE_CLANG_TIDY)
+  set(CMAKE_CXX_CLANG_TIDY "clang-tidy;-checks=bugprone-*,\
+  clang-analyzer-*,\
+  cppcoreguidelines-*,\
+  llvm-*,\
+  modernize-*,\
+  performance-*,\
+  -modernize-use-trailing-return-type,\
+  -cppcoreguidelines-pro-bounds-pointer-arithmetic,\
+  -cppcoreguidelines-pro-bounds-constant-array-index,\
+  -cppcoreguidelines-pro-type-vararg")
+  message(STATUS "clang-tidy is enabled.")
+else()
+  message(STATUS "clang-tidy is disabled. To enable it, use -DENABLE_CLANG_TIDY=ON.")
+endif()
+
 add_library(datetime)
 target_include_directories(datetime PUBLIC
   $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include/>
@@ -34,13 +54,19 @@ target_include_directories(datetime PUBLIC
 
 add_subdirectory(src)
 
+# disable clang-tidy (targets that follow will not be checked)
+set(CMAKE_CXX_CLANG_TIDY "")
+
 # The tests
 include(CTest)
 add_subdirectory(test/unit_tests)
 add_subdirectory(test/should_not_compile)
 find_library(sofa sofa_c)
 if (sofa)
   add_subdirectory(test/sofa)
+  message(STATUS "found sofa lib, will compile relevant tests")
+else()
+  message(STATUS "sofa lib not found; tests in test/sofa will not be compiled.")
 endif()
 enable_testing()
 

include/cdatetime.hpp

@@ -8,10 +8,10 @@
 namespace dso {
 
 /** Jan 1st 1980 for GPS Time */
-constexpr const long JAN61980 = 44'244L;
+constexpr const int JAN61980 = 44'244L;
 
 /** */
-constexpr const long JAN11901 = 15'385L;
+constexpr const int JAN11901 = 15'385L;
 
 /** @brief Seconds per day.
  * @warning This is not always true in case of UTC dates; the day a leap

include/dtfund.hpp

@@ -16,6 +16,7 @@
 #include <cstdio>
 #include <limits>
 #include <stdexcept>
+#include <cstdint>
 
 namespace dso {
 
@@ -37,7 +38,7 @@ class nanoseconds;
 
 namespace core {
 /** Number of days past at the end of non-leap and leap years. */
-constexpr const long month_day[2][13] = {
+constexpr const int month_day[2][13] = {
     {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
     {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}};
 
@@ -560,11 +561,15 @@ class month {
   constexpr static const char *short_names[] = {"Jan", "Feb", "Mar", "Apr",
                                                 "May", "Jun", "Jul", "Aug",
                                                 "Sep", "Oct", "Nov", "Dec"};
+  constexpr static const int SHORT_NAMES_LEN =
+      sizeof(short_names) / sizeof(short_names[0]);
 
   /** long month names. */
   constexpr static const char *long_names[] = {
       "January", "February", "March",     "April",   "May",      "June",
       "July",    "August",   "September", "October", "November", "December"};
+  constexpr static const int LONG_NAMES_LEN =
+      sizeof(short_names) / sizeof(short_names[0]);
 
   /** The month as underlying_type. */
   underlying_type m_month;
@@ -982,8 +987,14 @@ constexpr ymd_date mjd2ymd(long mjd) noexcept {
  */
 class modified_julian_day {
 public:
-  /** MJDs are represented as long ints. */
-  typedef long underlying_type;
+  /** Decide on the INT (underlying) type of modified_julian_day.
+   *
+   * underlying_type should be at least as long as int_32_t. Else 
+   * underlying_type will be a long.
+   * A 32bit int, has a range of -2147483648 to 2147483647. Should be enough!
+   */
+  typedef std::conditional<sizeof(int) >= sizeof(int32_t), int, int64_t>::type
+      underlying_type;
 
   /** Is fundamental datetime type */
   static constexpr bool is_dt_fundamental_type = true;

src/dat.cpp

@@ -4,12 +4,19 @@
 #include <cassert>
 #include <cstdio>
 
+namespace {
+/** just so we do not have magic numbers */
+constexpr const int MONTHS_IN_YEAR = 12;
+} /* unnamed namespace */
+
 namespace calendar_dat {
 /** Dates and Delta(AT)s */
 struct change {
   int iyear, month, delat;
   /** Combine year and month to form a date-ordered integer */
-  int ordered_int() const noexcept { return 12 * iyear + month; }
+  [[nodiscard]] int ordered_int() const noexcept {
+    return MONTHS_IN_YEAR * iyear + month;
+  }
 };
 constexpr const std::array<change, 28> changes = {
     {{1972, 1, 10}, {1972, 7, 11}, {1973, 1, 12}, {1974, 1, 13}, {1975, 1, 14},
@@ -42,7 +49,7 @@ int dso::dat(dso::year iy, dso::month im) noexcept {
   assert(iy >= dso::year(1972));
 
   /* Combine year and month to form a date-ordered integer... */
-  int m = 12 * iy.as_underlying_type() + im.as_underlying_type();
+  int m = MONTHS_IN_YEAR * iy.as_underlying_type() + im.as_underlying_type();
 
   /* ...and use it to find the preceding table entry. */
   auto it = std::find_if(

src/datetime_io_core.cpp

@@ -3,6 +3,11 @@
 #include <charconv>
 #include <cstdio>
 
+namespace {
+  /** just so it is not a magic number */
+  constexpr const int MONTHS_IN_YEAR = 12;
+}/* unnamed namespace */
+
 inline const char *skipws(const char *line) noexcept {
   const char *c = line;
   while (*c && (*c == ' ' || *c == '/' || *c == '-' || *c == 'T' || *c == ':' ||
@@ -31,11 +36,10 @@ inline int count_decimal_digits(const char *fltstr) noexcept {
     const char *dgtc = fltstr;
     while (std::isdigit(*dgtc))
       ++dgtc;
-    return (dgtc - fltstr);
-  } else {
-    /* no decimal digits */
-    return 0;
+    return (int)(dgtc - fltstr);
   }
+  /* no decimal digits */
+  return 0;
 }
 
 int dso::datetime_io_core::get_one_int(const char *str, int *ints,
@@ -151,7 +155,7 @@ int dso::datetime_io_core::get_two_ints_double(const char *str, int *ints,
   /* before parsing the next floating point number, count its decimal digits
    * If more than nanoseconds, issue a warning
    */
-  if (count_decimal_digits(skipws(c)) > 12) {
+  if (count_decimal_digits(skipws(c)) > MONTHS_IN_YEAR) {
     fprintf(stderr, "[WARNING] Reading in date with resolution larger than "
                     "nanoseconds will lead to loss of precision!\n");
     fprintf(stderr,

src/modified_julian_day.cpp

@@ -1,12 +1,17 @@
 #include "dtfund.hpp"
 
+namespace {
+  /** avoid magic numbers */
+  constexpr const int DAYS_IN_YEAR = 365;
+} /* unnamed namespace */
+
 dso::ydoy_date dso::modified_julian_day::to_ydoy() const noexcept {
-  const long days_fr_jan1_1901 = m_mjd - dso::JAN11901;
-  const long num_four_yrs = days_fr_jan1_1901 / 1461L;
-  const long years_so_far = 1901L + 4 * num_four_yrs;
-  const long days_left = days_fr_jan1_1901 - 1461 * num_four_yrs;
-  const long delta_yrs = days_left / 365 - days_left / 1460;
+  const int days_fr_jan1_1901 = m_mjd - dso::JAN11901;
+  const int num_four_yrs = days_fr_jan1_1901 / 1461;
+  const int years_so_far = 1901 + 4 * num_four_yrs;
+  const int days_left = days_fr_jan1_1901 - 1461 * num_four_yrs;
+  const int delta_yrs = days_left / DAYS_IN_YEAR - days_left / 1460;
 
-  return dso::ydoy_date(dso::year(years_so_far + delta_yrs),
-                        dso::day_of_year(days_left - 365 * delta_yrs + 1));
+  return {dso::year(years_so_far + delta_yrs),
+          dso::day_of_year(days_left - DAYS_IN_YEAR * delta_yrs + 1)};
 }

src/strmonth.cpp

@@ -9,14 +9,14 @@
 
 dso::month::month(const char *str) : m_month(0) {
   if (std::strlen(str) == 3) {
-    for (int i = 0; i < 12; i++) {
+    for (int i = 0; i < SHORT_NAMES_LEN; i++) {
       if (!strcasecmp(str, short_names[i])) {
         m_month = i + 1;
         break;
       }
     }
   } else if (std::strlen(str) > 3) {
-    for (int i = 0; i < 12; ++i) {
+    for (int i = 0; i < LONG_NAMES_LEN; ++i) {
       if (!strcasecmp(str, long_names[i])) {
         m_month = i + 1;
         break;

src/utc2tai.cpp

@@ -1,13 +1,13 @@
 #include "tpdate.hpp"
 
 dso::TwoPartDate dso::TwoPartDateUTC::utc2tai() const noexcept {
-  FDOUBLE taisec;
+  FDOUBLE taisec=0e0;
   int taimjd = this->utc2tai(taisec);
   return dso::TwoPartDate(taimjd, dso::FractionalSeconds{taisec});
 }
 
 dso::TwoPartDate dso::TwoPartDateUTC::utc2tt() const noexcept {
-  FDOUBLE ttsec;
+  FDOUBLE ttsec=0e0;
   int ttmjd = this->utc2tai(ttsec);
   return dso::TwoPartDate(ttmjd, dso::FractionalSeconds{ttsec});
 }

src/ydoy_date.cpp

@@ -1,7 +1,7 @@
 #include "dtfund.hpp"
 
 dso::ymd_date dso::ydoy_date::to_ymd() const noexcept {
-  int guess = static_cast<int>(__doy.as_underlying_type() * 0.032);
+  int guess = __doy.as_underlying_type() * 0.032;
   int leap = yr().is_leap();
   int more =
       ((dy().as_underlying_type() - dso::core::month_day[leap][guess + 1]) > 0);

src/ymd_date.cpp

@@ -23,6 +23,6 @@ dso::ydoy_date dso::ymd_date::to_ydoy() const {
   }
   int leap = yr().is_leap();
   int md = mn().as_underlying_type() - 1;
-  return dso::ydoy_date(yr(), dso::day_of_year(core::month_day[leap][md] +
-                                               dm().as_underlying_type()));
+  return {yr(), dso::day_of_year(core::month_day[leap][md] +
+                                               dm().as_underlying_type())};
 }