Escape necessary characters in SUMMARY on export

Escape semicolons, commas, and backslashes when exporting a calendar
item to iCal format.

Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>

1 files changed, 26 insertions, 5 deletions

diff --git a/src/ical.c b/src/ical.c
index 79b15de..2438351 100644
--- a/src/ical.c
+++ b/src/ical.c
@@ -72,6 +72,27 @@ static void ical_export_footer(FILE *);
 static const char *ical_recur_type[RECUR_TYPES] =
     { "", "DAILY", "WEEKLY", "MONTHLY", "YEARLY" };
 
+/* Escape characters in field before printing */
+static void ical_format_line(FILE * stream, char * field, char * msg)
+{
+	char * p;
+
+	fputs(field, stream);
+	for (p = msg; *p; p++) {
+		switch (*p) {
+			case ',':
+			case ';':
+			case '\\':
+				fprintf(stream, "\\%c", *p);
+				break;
+			default:
+			fputc(*p, stream);
+                break;
+		}
+	}
+	fputc('\n', stream);
+}
+
 /* iCal alarm notification. */
 static void ical_export_valarm(FILE * stream)
 {
@@ -130,7 +151,7 @@ static void ical_export_recur_events(FILE * stream, int export_uid)
 			}
 		}
 
-		fprintf(stream, "SUMMARY:%s\n", rev->mesg);
+		ical_format_line(stream, "SUMMARY:", rev->mesg);
 
 		if (export_uid) {
 			char *hash = recur_event_hash(rev);
@@ -153,7 +174,7 @@ static void ical_export_events(FILE * stream, int export_uid)
 		date_sec2date_fmt(ev->day, ICALDATEFMT, ical_date);
 		fputs("BEGIN:VEVENT\n", stream);
 		fprintf(stream, "DTSTART;VALUE=DATE:%s\n", ical_date);
-		fprintf(stream, "SUMMARY:%s\n", ev->mesg);
+		ical_format_line(stream, "SUMMARY:", ev->mesg);
 
 		if (export_uid) {
 			char *hash = event_hash(ev);
@@ -209,7 +230,7 @@ static void ical_export_recur_apoints(FILE * stream, int export_uid)
 			}
 		}
 
-		fprintf(stream, "SUMMARY:%s\n", rapt->mesg);
+		ical_format_line(stream, "SUMMARY:", rapt->mesg);
 		if (rapt->state & APOINT_NOTIFY)
 			ical_export_valarm(stream);
 
@@ -244,7 +265,7 @@ static void ical_export_apoints(FILE * stream, int export_uid)
 				(apt->dur / MININSEC) % HOURINMIN,
 				apt->dur % MININSEC);
 		}
-		fprintf(stream, "SUMMARY:%s\n", apt->mesg);
+		ical_format_line(stream, "SUMMARY:", apt->mesg);
 		if (apt->state & APOINT_NOTIFY)
 			ical_export_valarm(stream);
 
@@ -271,7 +292,7 @@ static void ical_export_todo(FILE * stream, int export_uid)
 		if (todo->completed)
 			fprintf(stream, "STATUS:COMPLETED\n");
 		fprintf(stream, "PRIORITY:%d\n", todo->id);
-		fprintf(stream, "SUMMARY:%s\n", todo->mesg);
+		ical_format_line(stream, "SUMMARY:", todo->mesg);
 
 		if (export_uid) {
 			char *hash = todo_hash(todo);