all unit tests successful, might have fixed bug

src/date_time_handling.c

@@ -5,37 +5,87 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <assert.h>
 
 // buffer needs to contain a string with a strlen of 15 (format: "xxxxxxxxTxxxxxx")
 // or a strlen of 16 (format: "YYYYmmddTHHMMSSZ")
-void get_date(char buffer[]) {
+void get_date (char buffer[]) {
 	// add 1 because strlen does not include the null character
-	size_t buffer_size = strlen(buffer) + 1;
+	size_t buffer_size = strlen (buffer) + 1;
-	time_t my_unix_ts = time(NULL);
+	time_t my_unix_ts = time (NULL);
-	struct tm* my_tm_local = localtime(&my_unix_ts);
+	struct tm* my_tm_local = localtime (&my_unix_ts);
-	if (strlen(buffer) == 15) {
+	if (strlen (buffer) == 15) {
-		strftime(buffer, buffer_size, "%Y%m%dT%H%M%S", my_tm_local);
+		strftime (buffer, buffer_size, "%Y%m%dT%H%M%S", my_tm_local);
-	} else if (strlen(buffer) == 16) {
+	}
-		strftime(buffer, buffer_size, "%Y%m%dT%H%M%SZ", my_tm_local);
+	else if (strlen (buffer) == 16) {
+		strftime (buffer, buffer_size, "%Y%m%dT%H%M%SZ", my_tm_local);
 	}
 }
 
 // 20230823T194138 -> 2023-08-23 19:41:38
-void pretty_print_date_time(char date_time[]) {
+// 20230823T194138Z -> 2023-08-23 19:41:38
+// 20241209 -> 2024-12-09
+// caller has to free() the returned char array
+char* pretty_date_time (char date_time[]) {
+	int pdt_len = 20;
+	if (!strchr (date_time, 'T')) {
+		pdt_len = 11;
+	}
+
+	char* pretty_dt = malloc (pdt_len);
+	memset(pretty_dt, '\0', pdt_len);
+	int dt_counter = 0;
+
+	if (!strcmp(date_time, "")) {
+		return pretty_dt;
+	}
+
+	for (int i = 0; i < (pdt_len-1); i++) {
+		if (i == 4 || i == 7) {
+			pretty_dt[i] = '-';
+			continue;
+		}
+		if (i == 13 || i == 16) {
+			pretty_dt[i] = ':';
+			continue;
+		}
+
+		if (date_time[dt_counter] == 'T') {
+			pretty_dt[i] = ' ';
+		} else {
+			pretty_dt[i] = date_time[dt_counter];
+		}
+		dt_counter++;
+	}
+
+	// null-terminate string
+	pretty_dt[strlen(pretty_dt)] = '\0';
+
+	return pretty_dt;
+}
+
+// 20230823T194138 -> 2023-08-23 19:41:38
+void pretty_print_date_time (char date_time[]) {
+	char* pdt = pretty_date_time(date_time);
+
+	printf("%s", pdt);
+
+	free(pdt);
+	/*
 	// copy date_time because strtok will destroy it
 	char date_time_copy[15] = "";
-	strcpy(date_time_copy, date_time);
+	strcpy (date_time_copy, date_time);
 
-	char *date = strtok(date_time, "T");
+	char* date = strtok (date_time, "T");
-	char *time = strtok(NULL, "T");
+	char* time = strtok (NULL, "T");
 	if (date == NULL) {
 		printf ("\nError: date points to NULL!\n");
-		exit(1);
+		exit (1);
 	}
 	printf ("%c%c%c%c-", date[0], date[1], date[2], date[3]);
 	printf ("%c%c-", date[4], date[5]);
 	printf ("%c%c", date[6], date[7]);
-	
+
 	if (time != NULL) {
 		printf (" %c%c:", time[0], time[1]);
 		printf ("%c%c:", time[2], time[3]);
@@ -43,63 +93,71 @@ void pretty_print_date_time(char date_time[]) {
 	}
 
 	// put variable date_time back together
-	strcpy(date_time, date_time_copy);
+	strcpy (date_time, date_time_copy);
+	*/
 }
 
-void marshall_date_time(char date_time[]) {
+void marshall_date_time (char date_time[]) {
-	char transformed_string[strlen(date_time)];
+	char transformed_string[strlen (date_time)];
 	int j = 0;
-	remove_nl_and_cr(date_time);
+	remove_nl_and_cr (date_time);
-	for (int i = 0; i<=strlen(date_time); i++) {
+	for (int i = 0; i <= strlen (date_time); i++) {
 		if (date_time[i] != ':' && date_time[i] != '-') {
 			if (date_time[i] == ' ') {
 				transformed_string[j] = 'T';
-			} else {
+			}
+			else {
 				transformed_string[j] = date_time[i];
 			}
-			
+
 			j++;
 		}
-	
+
 	}
-	memset(date_time, '\0', strlen(date_time));
+	memset (date_time, '\0', strlen (date_time));
-	strcpy(date_time, transformed_string);
+	strcpy (date_time, transformed_string);
 }
 
-void print_end_date(char end_date[], char start_date[]) {
+void print_end_date (char end_date[], char start_date[]) {
-	time_t start_uts = transform_date_to_unix_ts(start_date);
+	time_t start_uts = transform_date_to_unix_ts (start_date);
-	time_t end_uts = transform_date_to_unix_ts(end_date);
+	time_t end_uts = transform_date_to_unix_ts (end_date);
-	double time_difference = difftime(end_uts, start_uts);
+	double time_difference = difftime (end_uts, start_uts);
 
 	// end_date is all day event
-	if (strlen(end_date) == 8) {
+	if (strlen (end_date) == 8) {
 		if (time_difference == 86400) {
 			return;
-		} else {
+		}
+		else {
 			printf (" - ");
 			end_uts -= 86400;
-			char *end_date_minus_one = transform_unix_ts_to_date(end_uts);
+			char* end_date_minus_one =
-			pretty_print_date_time(end_date_minus_one);
+				transform_unix_ts_to_date (end_uts);
-			free(end_date_minus_one);
+			pretty_print_date_time (end_date_minus_one);
+			free (end_date_minus_one);
 			return;
 		}
-	} else {
+	}
+	else {
 		// end_date is not an all day event
 
-		char *end_date_chunk = strtok(end_date, "T");
+		char* end_date_chunk = strtok (end_date, "T");
-		char *end_time_chunk = strtok(NULL, "T");
+		char* end_time_chunk = strtok (NULL, "T");
-		char *start_date_chunk = strtok(start_date, "T");
+		char* start_date_chunk = strtok (start_date, "T");
 
 		printf (" - ");
 
 		// only print the end date if it is not the same as the start date
-		if (strcmp(start_date_chunk, end_date_chunk) != 0) {
+		if (strcmp (start_date_chunk, end_date_chunk) != 0) {
-			printf("%c%c%c%c-", end_date_chunk[0], end_date_chunk[1], \
+			printf ("%c%c%c%c-", end_date_chunk[0],
-			end_date_chunk[2], end_date_chunk[3]);
+				end_date_chunk[1], end_date_chunk[2],
-			printf("%c%c-", end_date_chunk[4], end_date_chunk[5]);
+				end_date_chunk[3]);
-			printf("%c%c ", end_date_chunk[6], end_date_chunk[7]);
+			printf ("%c%c-", end_date_chunk[4],
+				end_date_chunk[5]);
+			printf ("%c%c ", end_date_chunk[6],
+				end_date_chunk[7]);
 		}
-		
+
 		printf ("%c%c:", end_time_chunk[0], end_time_chunk[1]);
 		printf ("%c%c:", end_time_chunk[2], end_time_chunk[3]);
 		printf ("%c%c", end_time_chunk[4], end_time_chunk[5]);
@@ -107,40 +165,41 @@ void print_end_date(char end_date[], char start_date[]) {
 }
 
 // YYYYmmdd -> unix timestamp
-time_t transform_date_to_unix_ts(char date_str[]) {
+time_t transform_date_to_unix_ts (char date_str[]) {
 	time_t unix_stamp = 0;
-	int date_only = atoi(date_str);
+	int date_only = atoi (date_str);
-	struct tm my_tm = {0};
+	struct tm my_tm = { 0 };
 	my_tm.tm_year = date_only / 10000 - 1900;
 	my_tm.tm_mon = (date_only % 10000) / 100 - 1;
 	my_tm.tm_mday = date_only % 100;
 
-	unix_stamp = mktime(&my_tm);
+	unix_stamp = mktime (&my_tm);
 
 	return unix_stamp;
 }
 
 // unix timestamp -> YYYYmmdd
 // make sure to free the returned buffer
-char *transform_unix_ts_to_date(time_t unix_ts) {
+char* transform_unix_ts_to_date (time_t unix_ts) {
-	char *date_buffer = malloc(9);
+	char* date_buffer = malloc (9);
-	struct tm *my_tm;
+	struct tm* my_tm;
-	my_tm = localtime(&unix_ts);
+	my_tm = localtime (&unix_ts);
-	strftime(date_buffer, 9, "%Y%m%d", my_tm);
+	strftime (date_buffer, 9, "%Y%m%d", my_tm);
 
 	return date_buffer;
 }
 
-char *get_tz() {
+char* get_tz () {
-	char *timezone_path = malloc(256);
+	char* timezone_path = malloc (256);
-	ssize_t bytes_read = readlink("/etc/localtime", timezone_path, 255);
+	ssize_t bytes_read = readlink ("/etc/localtime", timezone_path, 255);
 
 	if (bytes_read != -1) {
 		// Null-terminate the string
-    	timezone_path[bytes_read] = '\0';
+		timezone_path[bytes_read] = '\0';
-	} else {
+	}
-		perror("readlink");
+	else {
-		exit(1);
+		perror ("readlink");
+		exit (1);
 	}
 
 	return timezone_path;

src/date_time_handling.h

@@ -5,6 +5,7 @@
 
 void get_date(char buffer[]);
 char *get_tz();
+char* pretty_date_time(char date_time[]);
 void pretty_print_date_time(char date_time[]);
 void marshall_date_time(char date_time[]);
 void print_end_date(char end_date[], char start_date[]);

unit-tests/test_pretty_print_date_time.c

@@ -1,7 +1,38 @@
 #include "../src/date_time_handling.h"
 #include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
 
 int main() {
+	// 1
+	char* pdt = pretty_date_time("20251215T080000Z");
+
+	assert(!strcmp(pdt, "2025-12-15 08:00:00"));
+
+	free(pdt);
+
+	// 2
+	char* pdt2 = pretty_date_time("20251215T080000");
+
+	assert(!strcmp(pdt2, "2025-12-15 08:00:00"));
+
+	free(pdt2);
+
+	// 3
+	char* pdt3 = pretty_date_time("");
+
+	assert(!strcmp(pdt3, ""));
+
+	free(pdt3);
+
+	// 4
+	char* pdt4 = pretty_date_time("20251215");
+
+	assert(!strcmp(pdt4, "2025-12-15"));
+
+	free(pdt4);
+
+	// 5
 	char current_date[] = "20240710T103000";
 
 	printf("current_date: %s\n", current_date);
@@ -13,6 +44,7 @@ int main() {
 	printf("strlen(current_date): %ld\n", strlen(current_date));
 
 	pretty_print_date_time("20251215T080000Z");
+	printf("\n");
 
 	return 0;
 }

unit-tests/test_print_upcoming.c

@@ -6,6 +6,8 @@ int main() {
 	// initialize empty list
 	struct event *head = NULL;
 
+	// 1
+	printf("\nTesting tests/failed_cal.ics:\n\n");
 	char *current_date = "20240710T113000";
 
 	printf("DEBUG - current_date: %s\n\n", current_date);
@@ -13,4 +15,10 @@ int main() {
 	parse_ics_file("../../tests/failed_cal.ics", &head);
 
 	print_upcoming(head, current_date, 0);
+
+	// 2
+	printf("\nTesting tests/calendar.ics:\n\n");
+	parse_ics_file("../../tests/calendar.ics", &head);
+
+	print_upcoming(head, current_date, 0);
 }