utils: diff between two calendar times in strings

diff --git a/daemon/lua/kres-gen.lua b/daemon/lua/kres-gen.lua
index a041ed603eb6acbbcb49d2348c9c03686ac36e17..eeb8ff7cad122f2255e101ebf6110ad449f53fea 100644 (file)
--- a/daemon/lua/kres-gen.lua
+++ b/daemon/lua/kres-gen.lua
@@ -315,6 +315,7 @@ int kr_zonecut_add(struct kr_zonecut *, const knot_dname_t *, const void *, int)
 _Bool kr_zonecut_is_empty(struct kr_zonecut *);
 void kr_zonecut_set(struct kr_zonecut *, const knot_dname_t *);
 uint64_t kr_now();
+const char *kr_strptime_diff(const char *, const char *, const char *, double *);
 void lru_free_items_impl(struct lru *);
 struct lru *lru_create_impl(unsigned int, knot_mm_t *, knot_mm_t *);
 void *lru_get_impl(struct lru *, const char *, unsigned int, unsigned int, _Bool, _Bool *);

diff --git a/daemon/lua/kres-gen.sh b/daemon/lua/kres-gen.sh
index 661a001f1262543c257fed00324e25802c086bad..538fe239e16d46c91b37966e066de877fc774060 100755 (executable)
--- a/daemon/lua/kres-gen.sh
+++ b/daemon/lua/kres-gen.sh
@@ -169,6 +169,7 @@ EOF
        kr_zonecut_is_empty
        kr_zonecut_set
        kr_now
+       kr_strptime_diff
        lru_free_items_impl
        lru_create_impl
        lru_get_impl

diff --git a/lib/utils.c b/lib/utils.c
index 1d4be296ff33b134efeb56f9d61ab8958670513f..fe9ab03b5895fcdae569d4d0aa3cdce955fd5dad 100644 (file)
--- a/lib/utils.c
+++ b/lib/utils.c
@@ -948,6 +948,38 @@ uint64_t kr_now()
        return uv_now(uv_default_loop());
 }
 
+const char *kr_strptime_diff(const char *format, const char *time1_str,
+                            const char *time0_str, double *diff) {
+       assert(format != NULL);
+       assert(time1_str != NULL);
+       assert(time0_str != NULL);
+       assert(diff != NULL);
+
+       struct tm time1_tm;
+       time_t time1_u;
+       struct tm time0_tm;
+       time_t time0_u;
+
+       char *err = strptime(time1_str, format, &time1_tm);
+       if (err == NULL || err != time1_str + strlen(time1_str))
+               return "strptime failed for time1";
+       time1_tm.tm_isdst = -1; /* determine if DST is active or not */
+       time1_u = mktime(&time1_tm);
+       if (time1_u == (time_t)-1)
+               return "mktime failed for time1";
+
+       err = strptime(time0_str, format, &time0_tm);
+       if (err == NULL || err != time0_str + strlen(time0_str))
+               return "strptime failed for time0";
+       time0_tm.tm_isdst = -1; /* determine if DST is active or not */
+       time0_u = mktime(&time0_tm);
+       if (time0_u == (time_t)-1)
+               return "mktime failed for time0";
+       *diff = difftime(time1_u, time0_u);
+
+       return NULL;
+}
+
 int knot_dname_lf2wire(knot_dname_t * const dst, uint8_t len, const uint8_t *lf)
 {
        knot_dname_t *d = dst; /* moving "cursor" as we write it out */

diff --git a/lib/utils.h b/lib/utils.h
index 8e4e1ad4bae36cfd1a876c6eaf6cf3c9909c9522..21eabac80a7ceefd3facc83ceebca18ea28d6d64 100644 (file)
--- a/lib/utils.h
+++ b/lib/utils.h
@@ -476,6 +476,15 @@ static inline int kr_dname_lf(uint8_t *dst, const knot_dname_t *src, bool add_wi
        return KNOT_EOK;
 }
 
+/**
+ * Difference between two calendar times specified as strings.
+ * \param format[in] format for strptime
+ * \param diff[out] result from C difftime(time1, time0)
+ */
+KR_EXPORT
+const char *kr_strptime_diff(const char *format, const char *time1_str,
+                            const char *time0_str, double *diff);
+
 /* Trivial non-inline wrappers, to be used in lua. */
 KR_EXPORT void kr_rrset_init(knot_rrset_t *rrset, knot_dname_t *owner,
                                uint16_t type, uint16_t rclass, uint32_t ttl);

diff --git a/tests/test_utils.c b/tests/test_utils.c
index 07856560eba064c57678ba8ecde226c3a25d0776..e6371c300f852275d1a549f679568d66d9411967 100644 (file)
--- a/tests/test_utils.c
+++ b/tests/test_utils.c
@@ -79,11 +79,44 @@ static void test_straddr(void **state)
        assert_int_not_equal(test_bitcmp(ip6_sub, ip6_out, 4), 0);
 }
 
+static void test_strptime_diff(void **state)
+{
+       char *format = "%Y-%m-%dT%H:%M:%S";
+       const char *errmsg = NULL;
+       double output;
+
+       errmsg = kr_strptime_diff(format,
+               "2019-01-09T12:06:04",
+               "2019-01-09T12:06:04", &output);
+       assert_true(errmsg == NULL);
+       /* double type -> equality is not reliable */
+       assert_true(output > -0.01 && output < 0.01);
+
+       errmsg = kr_strptime_diff(format,
+               "2019-01-09T12:06:04",
+               "2019-01-09T11:06:04", &output);
+       assert_true(errmsg == NULL);
+       /* double type -> equality is not reliable */
+       assert_true(output > -3600.01 && output < 3600.01);
+
+       /* invalid inputs */
+       errmsg = kr_strptime_diff(format,
+               "2019-01-09T25:06:04",
+               "2019-01-09T11:06:04", &output);
+       assert_true(errmsg != NULL);
+
+       errmsg = kr_strptime_diff("fail",
+               "2019-01-09T23:06:04",
+               "2019-01-09T11:06:04", &output);
+       assert_true(errmsg != NULL);
+}
+
 int main(void)
 {
        const UnitTest tests[] = {
                unit_test(test_strcatdup),
                unit_test(test_straddr),
+               unit_test(test_strptime_diff),
        };
 
        return run_tests(tests);