calendarspec: allow ranges in date and time specifications

Resolves #3042

1 files changed, 45 insertions, 19 deletions

diff --git a/src/basic/calendarspec.c b/src/basic/calendarspec.c
index 6e0bab9b94..54ab909ddf 100644
--- a/src/basic/calendarspec.c
+++ b/src/basic/calendarspec.c
@@ -32,6 +32,8 @@
 #include "parse-util.h"
 #include "string-util.h"
 
+/* Longest valid date/time range is 1970..2199 */
+#define MAX_RANGE_LEN   230
 #define BITS_WEEKDAYS   127
 
 static void free_chain(CalendarComponent *c) {
@@ -448,8 +450,26 @@ static int parse_component_decimal(const char **p, bool usec, unsigned long *res
         return 0;
 }
 
+static int const_chain(int value, CalendarComponent **c) {
+        CalendarComponent *cc = NULL;
+
+        assert(c);
+
+        cc = new0(CalendarComponent, 1);
+        if (!cc)
+                return -ENOMEM;
+
+        cc->value = value;
+        cc->repeat = 0;
+        cc->next = *c;
+
+        *c = cc;
+
+        return 0;
+}
+
 static int prepend_component(const char **p, bool usec, CalendarComponent **c) {
-        unsigned long value, repeat = 0;
+        unsigned long i, value, range_end, range_inc, repeat = 0;
         CalendarComponent *cc;
         int r;
         const char *e;
@@ -471,6 +491,30 @@ static int prepend_component(const char **p, bool usec, CalendarComponent **c) {
 
                 if (repeat == 0)
                         return -ERANGE;
+        } else if (e[0] == '.' && e[1] == '.') {
+                e += 2;
+                r = parse_component_decimal(&e, usec, &range_end);
+                if (r < 0)
+                        return r;
+
+                if (value >= range_end)
+                        return -EINVAL;
+
+                range_inc = usec ? USEC_PER_SEC : 1;
+
+                /* Don't allow impossibly large ranges... */
+                if (range_end - value >= MAX_RANGE_LEN * range_inc)
+                        return -EINVAL;
+
+                /* ...or ranges with only a single element */
+                if (range_end - value < range_inc)
+                        return -EINVAL;
+
+                for (i = value; i <= range_end; i += range_inc) {
+                        r = const_chain(i, c);
+                        if (r < 0)
+                                return r;
+                }
         }
 
         if (*e != 0 && *e != ' ' && *e != ',' && *e != '-' && *e != ':')
@@ -495,24 +539,6 @@ static int prepend_component(const char **p, bool usec, CalendarComponent **c) {
         return 0;
 }
 
-static int const_chain(int value, CalendarComponent **c) {
-        CalendarComponent *cc = NULL;
-
-        assert(c);
-
-        cc = new0(CalendarComponent, 1);
-        if (!cc)
-                return -ENOMEM;
-
-        cc->value = value;
-        cc->repeat = 0;
-        cc->next = *c;
-
-        *c = cc;
-
-        return 0;
-}
-
 static int parse_chain(const char **p, bool usec, CalendarComponent **c) {
         const char *t;
         CalendarComponent *cc = NULL;