diff options
| author | Pixel <Pixel> | 2001-09-20 23:27:01 +0000 |
|---|---|---|
| committer | Pixel <Pixel> | 2001-09-20 23:27:01 +0000 |
| commit | 8346d0774d2d1e076038db27f65f1d082a460f16 (patch) | |
| tree | 132f84cf1ef45d5006a2b1d52d4d40b1e8e51abc /lib/checkargs.c | |
Initial revision
Diffstat (limited to 'lib/checkargs.c')
| -rw-r--r-- | lib/checkargs.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/lib/checkargs.c b/lib/checkargs.c new file mode 100644 index 0000000..e1c97be --- /dev/null +++ b/lib/checkargs.c @@ -0,0 +1,85 @@ +/* datedif - calculates the difference in days between two dates
+ * Copyright (C) 2000 Micael Widell contact: xeniac@linux.nu
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdlib.h> +#include <string.h> +
+int isDateArgument(char* dateString) {
+
+ const int MONTHS[] = {31,0,31,30,31,30,31,31,30,31,30,31};
+ int i, day, month, year;
+ char buffer[5];
+
+ /* 'today' is a valid date */
+ if (strcmp(dateString, "today") == 0)
+ return 1;
+
+ /* Numeric dates must be eight characters long */
+ if (8 != strlen(dateString))
+ return 0;
+
+ /* Check that the date is entirely formed of numbers */
+ for (i = 0; i < 8; i++) {
+ if (dateString[i] < '0' || dateString[i] > '9')
+ return 0;
+ }
+
+ /* Check that the date exists */
+ memset(buffer, 0, 5);
+ strncpy(buffer, dateString + 6, 2);
+ day = atoi(buffer);
+ strncpy(buffer, dateString + 4, 2);
+ month = atoi(buffer);
+ month -= 1;
+ strncpy(buffer, dateString, 4);
+ year = atoi(buffer);
+
+ /* Validate month */
+ if (month < 0 || month > 11)
+ return 0;
+
+ /* Validating dates is simple when the date does not fall into February */
+ if (1 != month) {
+ if (day < 1 || day > MONTHS[month])
+ return 0;
+ } else {
+ int feb = 28;
+
+ /* Februarys are a bit tougher issue */
+ if (0 == year % 4) {
+ if (0 == year % 100) {
+ if (0 == year % 400) {
+ feb = 29;
+ } else {
+ feb = 28;
+ }
+ } else {
+ feb = 29;
+ }
+ }
+ if (day < 1 || day > feb)
+ return 0;
+ }
+
+ /* Avoid user from using dates before 16000301, since those will result in
+ incorrect output */
+ if(16000301 > atoi(dateString))
+ return 0;
+
+ return 1;
+}
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