Add tests for tzset POSIX timezone string compliance

- patch from jdbouleu <hi@jdoubleu.de>

  - create time.exp and tzset.c files in newlib/testsuite/newlib.time

2 files changed, 175 insertions, 0 deletions

diff --git a/newlib/testsuite/newlib.time/time.exp b/newlib/testsuite/newlib.time/time.exp
new file mode 100644
index 000000000..3fce2306e
--- /dev/null
+++ b/newlib/testsuite/newlib.time/time.exp
@@ -0,0 +1,12 @@
+# Copyright (C) 2022 jdoubleu. All rights reserved.
+#
+# Permission to use, copy, modify, and distribute this software
+# is freely granted, provided that this notice is preserved.
+#
+
+load_lib passfail.exp
+
+set exclude_list {
+}
+
+newlib_pass_fail_all -x $exclude_list
diff --git a/newlib/testsuite/newlib.time/tzset.c b/newlib/testsuite/newlib.time/tzset.c
new file mode 100644
index 000000000..0e5b196c6
--- /dev/null
+++ b/newlib/testsuite/newlib.time/tzset.c
@@ -0,0 +1,163 @@
+/* Test that valid POSIX timezone strings are correctly parsed by tzset(3). */

+#include <stdio.h>

+#include <stdlib.h>

+

+// BEGIN test vectors

+#include <time.h>

+#include <limits.h>

+

+#define IN_SECONDS(h, m, s) ((h) * 3600 + (m) * 60 + (s))

+#define NO_TIME INT_MIN

+

+struct tz_test {

+    const char* tzstr;

+    int offset_seconds;

+    int dst_offset_seconds;

+};

+

+extern struct tm winter_tm;

+extern struct tm summer_tm;

+extern const time_t winter_time;

+extern const time_t summer_time;

+extern struct tz_test test_timezones[];

+

+// winter time is March, 21st 2022 at 8:15pm and 20 seconds

+struct tm winter_tm = {

+    .tm_sec     = 20,

+    .tm_min     = 15,

+    .tm_hour    = 20,

+    .tm_mday    = 21,

+    .tm_mon     = 3 - 1,

+    .tm_year    = 2022 - 1900,

+    .tm_isdst   = 0

+};

+

+// summer time is July, 15th 2022 at 10:50am and 40 seconds

+struct tm summer_tm = {

+    .tm_sec     = 40,

+    .tm_min     = 50,

+    .tm_hour    = 10,

+    .tm_mday    = 15,

+    .tm_mon     = 7 - 1,

+    .tm_year    = 2022 - 1900,

+    .tm_isdst   = 1

+};

+

+// UTC unix time for the winter time

+const time_t winter_time = 1647893720;

+const time_t summer_time = 1657882240;

+

+struct tz_test test_timezones[] = {

+    /*

+     * creating test vectors based on the POSIX spec (https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03)

+     */

+    // normal std names

+    {"MAR1",         IN_SECONDS(1, 0, 0),    NO_TIME},

+    {"MAR-1",       -IN_SECONDS(1, 0, 0),    NO_TIME},

+    {"MAR+2",        IN_SECONDS(2, 0, 0),    NO_TIME},

+    {"MAR7",         IN_SECONDS(7, 0, 0),    NO_TIME},

+    {"MAR-7",       -IN_SECONDS(7, 0, 0),    NO_TIME},

+    {"MARS5",        IN_SECONDS(5, 0, 0),    NO_TIME},

+    {"MARSM5",       IN_SECONDS(5, 0, 0),    NO_TIME},

+    {"MARSMOON5",    IN_SECONDS(5, 0, 0),    NO_TIME},   // assuming TZNAME_MAX >= 8

+    {"MARS5:23:42",  IN_SECONDS(5, 23, 42),  NO_TIME},

+    {"SUN-7:14:24", -IN_SECONDS(7, 14, 24),  NO_TIME},

+    // with DST

+    {"MAR5SMAR",                IN_SECONDS(5, 0, 0), IN_SECONDS(4, 0, 0)},  // only DST name

+    {"MAR5SMAR2",               IN_SECONDS(5, 0, 0), IN_SECONDS(2, 0, 0)},  // DST name with offset

+    {"MAR3SMAR-3",              IN_SECONDS(3, 0, 0), -IN_SECONDS(3, 0, 0)},

+    {"MARSWINTER4MARSUMMER",    IN_SECONDS(4, 0, 0), IN_SECONDS(3, 0, 0)},

+    {"MARSWINTER4MARSUMMER3",   IN_SECONDS(4, 0, 0), IN_SECONDS(3, 0, 0)},

+    // with DST IN_SECONDSs

+    {"WMARS3SMARS,J80",                                 IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,J80,J134",                            IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,79",                                  IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,76,134",                              IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,76/02,134/03",                        IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,76/02:15:45,134/03:40:20",            IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+    {"WMARS3SMARS,M3.4.1/02:15:45,M8.3.1/03:40:20",     IN_SECONDS(3, 0, 0), IN_SECONDS(2, 0, 0)},

+

+    // special std names

+    {"<UNK>-1",                                 -IN_SECONDS(1, 0, 0),     NO_TIME},

+    {"<UNKNOWN>-2",                             -IN_SECONDS(2, 0, 0),     NO_TIME},                  // require TZNAME_MAX >= 7 + 1

+    {"<003>3",                                   IN_SECONDS(3, 0, 0),     NO_TIME},

+    {"<+04>4",                                   IN_SECONDS(4, 0, 0),     NO_TIME},

+    {"<-05>-5",                                 -IN_SECONDS(5, 0, 0),     NO_TIME},

+    {"<A-5>6",                                   IN_SECONDS(6, 0, 0),     NO_TIME},

+    {"<+A5>-7",                                 -IN_SECONDS(7, 0, 0),     NO_TIME},

+    {"<0123456>8",                               IN_SECONDS(8, 0, 0),     NO_TIME},

+    {"<0A1B2C3>9",                               IN_SECONDS(9, 0, 0),     NO_TIME},

+    {"<RD-04>-4<RD+005>5",                      -IN_SECONDS(4, 0, 0),     IN_SECONDS(5, 0, 0)},

+    {"<WINT+03>3<SUM+02>",                       IN_SECONDS(3, 0, 0),     IN_SECONDS(2, 0, 0)},

+    {"<WINT+03>3<SUM+02>2",                      IN_SECONDS(3, 0, 0),     IN_SECONDS(2, 0, 0)},

+    {"<WINT+03>3:15<SUM+02>2:30:15",             IN_SECONDS(3, 15, 0),    IN_SECONDS(2, 30, 15)},

+    {"<H3M15>3:15<H2M30S15>2:30:15",             IN_SECONDS(3, 15, 0),    IN_SECONDS(2, 30, 15)},   // requires TZNAME_MAX >= 8 + 1

+    {"<+H6M20S12>6:20:12<-H4M40S14>-4:40:14",    IN_SECONDS(6, 20, 12),  -IN_SECONDS(4, 40, 14)},   // requires TZNAME_MAX >= 9 + 1

+    {"<+0123456789ABCDEF>3:33:33",               IN_SECONDS(3, 33, 33),   NO_TIME},                 // truncates the name (17 + 1)

+

+    /* 

+     * real-world test vectors.

+     * IN_SECONDSzones extracted from the tzdb (https://github.com/eggert/tz#2019e).

+     * The IN_SECONDSzone strings can also be obtained from https://raw.githubusercontent.com/nayarsystems/posix_tz_db/master/zones.csv.

+     */

+    { /* Etc/GMT-14 */              "<+14>-14",                        -IN_SECONDS(14, 0, 0),     NO_TIME},

+    { /* Etc/GMT+12 */              "<-12>12",                          IN_SECONDS(12, 0, 0),     NO_TIME},

+    { /* Africa/Casablanca */       "<+01>-1",                         -IN_SECONDS(1, 0, 0),      NO_TIME},

+    { /* America/Araguaina */       "<-03>3",                           IN_SECONDS(3, 0, 0),      NO_TIME},

+    { /* America/Asuncion */        "<-04>4<-03>,M10.1.0/0,M3.4.0/0",   IN_SECONDS(4, 0, 0),      IN_SECONDS(3, 0, 0)},

+    { /* America/Los_Angeles */     "PST8PDT,M3.2.0,M11.1.0",           IN_SECONDS(8, 0, 0),      IN_SECONDS(7, 0, 0)},

+    { /* America/New_York */        "EST5EDT,M3.2.0,M11.1.0",           IN_SECONDS(5, 0, 0),      IN_SECONDS(4, 0, 0)},

+    { /* America/Scoresbysund */    "<-01>1<+00>,M3.5.0/0,M10.5.0/1",   IN_SECONDS(1, 0, 0),      IN_SECONDS(0, 0, 0)},

+    { /* Asia/Colombo */            "<+0530>-5:30",                    -IN_SECONDS(5, 30, 0),     NO_TIME},

+    { /* Europe/Berlin */           "CET-1CEST,M3.5.0,M10.5.0/3",      -IN_SECONDS(1, 0, 0),     -IN_SECONDS(2, 0, 0)},

+

+    // END of list

+    {NULL, NO_TIME, NO_TIME}

+};

+

+// helper macros

+#define FOR_TIMEZONES(iter_name) for (struct tz_test* iter_name = test_timezones; iter_name->tzstr != NULL; ++iter_name)

+

+// END test vectors

+

+static int failed = 0;

+

+#define TEST_ASSERT_EQUAL_INT_MESSAGE(...) assert_equal(__VA_ARGS__)

+void assert_equal(int lhs, int rhs, const char* msg)

+{

+    if (lhs != rhs)

+    {

+        printf("Assertion failed! Expected %d to equal %d. %s\n", lhs, rhs, msg);

+        ++failed;

+    }

+}

+

+void test_TimezoneStrings(void)

+{

+    char buffer[128];

+

+    FOR_TIMEZONES(ptr)

+    {

+        setenv("TZ", ptr->tzstr, 1);

+        tzset();

+

+        snprintf(buffer, 128, "winter time, timezone = \"%s\"", ptr->tzstr);

+

+        struct tm winter_tm_copy = winter_tm; // copy

+        TEST_ASSERT_EQUAL_INT_MESSAGE(winter_time + ptr->offset_seconds, mktime(&winter_tm_copy), buffer);

+

+        if (ptr->dst_offset_seconds != NO_TIME)

+        {

+            snprintf(buffer, 128, "summer time, timezone = \"%s\"", ptr->tzstr);

+

+            struct tm summer_tm_copy = summer_tm; // copy

+            TEST_ASSERT_EQUAL_INT_MESSAGE(summer_time + ptr->dst_offset_seconds, mktime(&summer_tm_copy), buffer);

+        }

+    }

+}

+

+int main()

+{

+    test_TimezoneStrings();

+    exit (failed);

+}
\ No newline at end of file