Add some more leap second support

src/libiso8601/build.monolithic

@@ -11,7 +11,7 @@ then
     MONOLITHIC_SOURCE="$(echo src/libiso8601/{TopHeader,types,functions,BottomHeader}.h)"
     make_monolithic ${HDR} Ch || return 1
 
-    MONOLITHIC_SOURCE="$(echo src/libiso8601/{TopSource,c_library,calc,parser,print,manip,leap}.c)"
+    MONOLITHIC_SOURCE="$(echo src/libiso8601/{TopSource,leap,c_library,calc,parser,print,manip}.c)"
     make_monolithic ${SRC} C || return 1
 
     libiso8601_MONOLITHIC=1

src/libiso8601/functions.h

@@ -67,11 +67,14 @@ void iso8601_print(char* str, int amt, const struct iso8601_date* date,
     const struct iso8601_details* details);
 
 /* manip.c */
+int iso8601_lt(const struct iso8601_date* d1, const struct iso8601_date* d2);
+int iso8601_lte(const struct iso8601_date* d1, const struct iso8601_date* d2);
 void iso8601_add_seconds(struct iso8601_date* date, long seconds);
 
 /* leap.c */
 int iso8601_seconds_leap(const struct iso8601_date* date);
 int iso8601_valid_leap(const struct iso8601_date* date);
+int iso8601_leap_elapsed(const struct iso8601_date* start, const struct iso8601_date* end);
 
 /* options for text editors
 kate: replace-trailing-space-save true; space-indent true; tab-width 4;

src/libiso8601/leap.c

@@ -67,6 +67,29 @@ int iso8601_valid_leap(const struct iso8601_date* date)
 
 
 
+static int _leap_elapsed_day(int sday, int eday)
+{
+    int spos, epos;
+
+    for(spos = 0; (unsigned)spos < sizeof(leap_second_days) / sizeof(int); ++spos) {
+        if(sday <= leap_second_days[spos]) break;
+    }
+    for(epos = 0; (unsigned)epos < sizeof(leap_second_days) / sizeof(int); ++epos) {
+        if(eday <= leap_second_days[epos]) break;
+    }
+
+    return spos - epos;
+}
+
+
+
+int iso8601_leap_elapsed(const struct iso8601_date* start, const struct iso8601_date* end)
+{
+    return _leap_elapsed_day(start->day, end->day);
+}
+
+
+
 /* options for text editors
 kate: replace-trailing-space-save true; space-indent true; tab-width 4;
 vim: expandtab:ts=4:sw=4

src/libiso8601/manip.c

@@ -7,19 +7,56 @@
 
 
 
+int iso8601_lt(const struct iso8601_date* d1, const struct iso8601_date* d2)
+{
+    if(d1->day < d2->day) return 1;
+    if(d1->day > d2->day) return 0;
+    if(d1->sec < d2->sec) return 1;
+    if(d1->sec > d2->sec) return 0;
+    if(d1->nsec < d2->nsec) return 0;
+    return 1;
+}
+
+
+
+int iso8601_lte(const struct iso8601_date* d1, const struct iso8601_date* d2)
+{
+    if(d1->day < d2->day) return 1;
+    if(d1->day > d2->day) return 0;
+    if(d1->sec < d2->sec) return 1;
+    if(d1->sec > d2->sec) return 0;
+    if(d1->nsec < d2->nsec) return 0;
+    return d1->nsec == d2->nsec;
+}
+
+
+
 void iso8601_add_seconds(struct iso8601_date* date, long seconds)
 {
+    int sday;
     ldiv_t qr;
 
-    // TODO: leap second support
-
+    sday = date->day;
     qr = ldiv(seconds + date->sec, 86400);
     date->day += qr.quot;
+
     date->sec = qr.rem;
     if(date->sec < 0) {
         --date->day;
         date->sec += 86400;
     }
+
+    /* leap second correction */
+    if(sday != date->day) {
+        date->sec += _leap_elapsed_day(sday, date->day);
+        if(date->sec < 0) {
+            --date->day;
+            date->sec += iso8601_seconds_leap(date);
+        } else if(date->sec >= iso8601_seconds_leap(date)) {
+            date->sec -= iso8601_seconds_leap(date);
+            ++date->day;
+        }
+    }
 }
 
 

src/tests/leap.c

@@ -0,0 +1,267 @@
+/* libiso8601/src/tests/leap.c
+ *
+ *  (c)2007, Laurence Withers, <l@lwithers.me.uk>.
+ *  Released under the GNU GPLv2. See file COPYING or
+ *  http://www.gnu.org/copyleft/gpl.html for details.
+*/
+
+#include "iso8601.h"
+
+#include <stdio.h>
+#include <string.h>
+
+
+
+int leap_diff(const char* s1, const char* s2, int* diff)
+{
+    struct iso8601_date d1, d2;
+
+    if(iso8601_parse(s1, &d1, 0, 0) || iso8601_parse(s2, &d2, 0, 0)) {
+        fprintf(stderr, "Unable to parse ``%s'' or ``%s'' (%m).", s1, s2);
+        return -1;
+    }
+
+    *diff = iso8601_leap_elapsed(&d1, &d2);
+    return 0;
+}
+
+
+
+int regression1(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2005, 12, 31);
+    oday = d.day;
+    d.sec = 0;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != oday) | (d.sec != 86400);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday + 1)) | (d.sec != 86399);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+int regression2(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2005, 12, 31);
+    oday = d.day;
+    d.sec = 86399;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != (oday + 1)) | (d.sec != 86398);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday + 2)) | (d.sec != 86398);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+int regression3(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2005, 12, 31);
+    oday = d.day;
+    d.sec = 86400;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != (oday + 1)) | (d.sec != 86399);
+
+    iso8601_add_seconds(&d, 86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday + 2)) | (d.sec != 86399);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+int regression4(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2006, 1, 1);
+    oday = d.day;
+    d.sec = 86399;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != (oday - 1)) | (d.sec != 86400);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday - 1)) | (d.sec != 0);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+int regression5(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2006, 1, 2);
+    oday = d.day;
+    d.sec = 86398;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != (oday - 1)) | (d.sec != 86398);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday - 2)) | (d.sec != 86399);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+int regression6(void)
+{
+    struct iso8601_date d;
+    char s1[30], s2[30], s3[30];
+    int ret = 0, oday;
+
+    iso8601_from_cal(&d, 2006, 1, 2);
+    oday = d.day;
+    d.sec = 86399;
+    d.nsec = 0;
+    iso8601_print(s1, sizeof(s1), &d, 0);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s2, sizeof(s2), &d, 0);
+    ret |= (d.day != (oday - 1)) | (d.sec != 86399);
+
+    iso8601_add_seconds(&d, -86400);
+    iso8601_print(s3, sizeof(s3), &d, 0);
+    ret |= (d.day != (oday - 2)) | (d.sec != 86400);
+
+    printf("%s -> %s -> %s\n", s1, s2, s3);
+
+    return ret;
+}
+
+
+
+struct regression_test {
+    const char* name;
+    int (*func)(void);
+};
+
+struct regression_test regression_tests[] = {
+    { "Start of leap day, +86400s", regression1 },
+    { "Near end of leap day, +86400s", regression2 },
+    { "End of leap day, +86400s", regression3 },
+    { "Start of post-leap day, -86400s", regression4 },
+    { "Near end of post-leap day, -86400s", regression5 },
+    { "End of post-leap day, -86400s", regression6 },
+    { 0, 0 }
+};
+
+
+
+int regression(void)
+{
+    int ret = 0;
+    struct regression_test* test;
+
+    for(test = regression_tests; test->func; ++test) {
+        if(test->func()) {
+            fprintf(stderr, "%s failed.\n", test->name);
+            ++ret;
+        }
+    }
+
+    return ret;
+}
+
+
+
+int main(int argc, char* argv[])
+{
+    int ret = 0, diff;
+
+    if(argc == 2 && !strcmp(argv[1], "--print-summary")) {
+        fputs("Leap second regression test.\n", stdout);
+        return 0;
+    }
+
+    switch(argc) {
+    case 1:
+        ret = regression();
+        fputs("Alternative use: pass two dates on commandline to see elapsed leap seconds.\n", 
+            stdout);
+        break;
+
+    case 3:
+        ret = leap_diff(argv[1], argv[2], &diff);
+        if(!ret) printf("Leap second correction: %d\n", diff);
+        break;
+
+    case 2:
+        if(!strcmp(argv[1], "--print-summary")) {
+            printf("Leap second regression test.");
+            return 0;
+        }
+        /* fall through */
+    default:
+        ret = 1;
+        fputs("Either zero or two arguments expected.\n", stderr);
+        break;
+    }
+
+    /* TODO */
+
+    return ret;
+}
+
+/* options for text editors
+kate: replace-trailing-space-save true; space-indent true; tab-width 4;
+vim: expandtab:ts=4:sw=4
+*/