.gitignore

@@ -1,2 +1,3 @@
 a.out
 .gitconfig
+*.o

src/Makefile

@@ -1,3 +1,22 @@
+CC = gcc
+CFLAGS = -Wall
+
+# List of all source files (assuming they're all in the same directory)
+SRC_FILES = $(wildcard *.c)
+
+# Generate a list of object files by replacing the .c extension with .o
+OBJ_FILES = $(SRC_FILES:.c=.o)
+
+ics_analyzer: $(OBJ_FILES)
+	gcc -Wall $(OBJ_FILES) -o ics_analyzer
+
+main.o: main.c
+	$(CC) $(CFLAGS) -c $<
+
+# use implicit rule to compile C source files to object files
+%.o: %.c %.h
+	$(CC) $(CFLAGS) -c $<
+
 .PHONY:all
 all:
 	gcc -Wall *.c
@@ -10,15 +29,15 @@ debug:
 .PHONY:run
 run:
 	gcc -Wall *.c
-	./a.out
+	./ics_analyzer
 
 .PHONY:install
 install: a.out
-	cp a.out /usr/local/bin/ics_analyzer
+	cp ics_analyzer /usr/local/bin/ics_analyzer
 
 .PHONY:clean
 clean:
-	-rm a.out
+	-rm ics_analyzer *.o
 
 .PHONY:uninstall
 uninstall:
@@ -26,8 +45,8 @@ uninstall:
 
 .PHONY:test
 test:
-	./a.out
+	./ics_analyzer
 	@echo
-	./a.out -h
+	./ics_analyzer -h
 	@echo
-	./a.out -f ../tests/calendar.ics
+	./ics_analyzer -f ../tests/calendar.ics

src/cli_arg_parsing.c

@@ -1,3 +1,4 @@
+#include "insert_event.h"
 #include "cli_arg_parsing.h"
 #include <stdio.h>
 #include <stdlib.h>
@@ -5,37 +6,37 @@
 #include <string.h>
 
 void usage() {
-  printf ("-h\tprint this help\n");
-  printf ("-f\tspecify ics file path\n");
-  exit(0);
+	printf ("-h\tprint this help\n");
+	printf ("-f\tspecify ics file path\n");
+	exit(0);
 }
 
 void get_cli_args(int argc, char **argv, char **file_name) {
-  int opt = 0;
+	int opt = 0;
 
-  memset(file_name, '\0', strlen(*file_name));
+	memset(file_name, '\0', strlen(*file_name));
 
-  if (argc < 2) {
-    char *home = getenv("HOME");
-    *file_name = home;
+	char *home = getenv("HOME");
+	*file_name = home;
 
-    if (home != NULL) {
-      strcat(*file_name, "/.local/share/evolution/calendar/system/calendar.ics");
-    } else {
-      printf ("Environment variable HOME is not set.\n");
-      exit(1);
-    }
-    return;
-  }
+	if (home != NULL) {
+	  strcat(*file_name, "/.local/share/evolution/calendar/system/calendar.ics");
+	} else {
+	  printf ("Environment variable HOME is not set.\n");
+	  exit(1);
+	}
 
-  while ((opt = getopt(argc, argv, "f:h")) != -1) {
-    switch(opt) {
-      case 'f':
-      *file_name = optarg;
-      break;
-      case 'h':
-      usage();
-    }
-  }
+	while ((opt = getopt(argc, argv, "f:hi")) != -1) {
+    	switch(opt) {
+		  case 'f':
+		  *file_name = optarg;
+		  break;
+		  case 'h':
+		  usage();
+		  break;
+		  case 'i':
+		  insert_event(*file_name);
+		  break;
+    	}
+	}
 }
-

src/insert_event.c

@@ -0,0 +1,33 @@
+#include "insert_event.h"
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+void insert_event(char *file_name) {
+	int myfd = open(file_name, O_APPEND | O_WRONLY);
+
+	char summary_buf[256] = "SUMMARY:";
+
+	char *input_buffer = &summary_buf[8];
+
+	printf("Insert a new event\n");
+	printf("SUMMARY: ");
+	fgets (input_buffer, (sizeof(summary_buf)-strlen(summary_buf)), stdin);
+
+	if (strchr(input_buffer, '\n') == NULL)
+		printf ("The input has been truncated to:\n%s\n", input_buffer);
+
+	// modify the string to have \r\n line ending
+	summary_buf[strlen(summary_buf)+1] = '\0';
+	summary_buf[strlen(summary_buf)-1] = '\r';
+	summary_buf[strlen(summary_buf)] = '\n';
+
+	write(myfd, "BEGIN:VEVENT\r\n", strlen("BEGIN:VEVENT\r\n"));
+	write(myfd, summary_buf, strlen(summary_buf));
+
+	close(myfd);
+
+	exit(0);
+}

src/insert_event.h

@@ -0,0 +1,3 @@
+#pragma once
+
+void insert_event(char *file_name);

src/main.c

@@ -14,8 +14,8 @@
 #include <limits.h>
 
 int main(int argc, char **argv) {
-  char *ics_path = "";
-  get_cli_args(argc, argv, &ics_path);
+	char *ics_path = "";
+	get_cli_args(argc, argv, &ics_path);
 
 	char my_line[4096] = "";