Add comments to mygrep, begin implementing the http client

.gitignore

@@ -1,2 +1,3 @@
 .vscode/
 *.out
+*.o

http/Makefile

@@ -0,0 +1,27 @@
+CC = gcc
+CFLAGS = -std=c99 -pedantic -Wall -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_SVID_SOURCE -D_POSIX_C_SOURCE=200809L -g -c
+TARGET_1 = client
+TARGET_2 = server
+
+all: $(TARGET_1).c $(TARGET_2).c
+	$(CC) $(CFLAGS) $(TARGET_1).c $(TARGET_2).c
+	$(CC) $(TARGET_1).o -o $(TARGET_1)
+	$(CC) $(TARGET_2).o -o $(TARGET_2)
+
+client: $(TARGET_1).c
+	$(CC) $(CFLAGS) $(TARGET_1).c
+	$(CC) $(TARGET_1).o -o $(TARGET_1)
+
+server: $(TARGET_2).c
+	$(CC) $(CFLAGS) $(TARGET_2).c
+	$(CC) $(TARGET_2).o -o $(TARGET_2)
+
+install:
+	cp $(TARGET_1) /usr/local/bin/myhttp-$(TARGET_1)
+	cp $(TARGET_2) /usr/local/bin/myhttp-$(TARGET_2)
+
+clean:
+	$(RM) $(TARGET_1).o
+	$(RM) $(TARGET_1)
+	$(RM) $(TARGET_2).o
+	$(RM) $(TARGET_2)

http/client.c

@@ -0,0 +1,84 @@
+#define _GNU_SOURCE ///< in order for optarg to be defined
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include "shared/http.h"
+
+int main(int argc, char *argv[]) {
+    check_opts_number(argc);
+
+    int port = 80;
+    char *ofile = NULL;
+    char *dir = NULL;
+    char *url = NULL;
+    int c;
+
+    /// Process the options
+    while((c = getopt(argc, argv, "p:o:d:h")) != -1) {
+        switch(c) {
+            case 'p':
+                port = atoi(optarg);
+                break;
+            case 'o':
+                ofile = optarg;
+                break;
+            case 'd':
+                dir = optarg;
+                break;
+            case 'h':
+                printf("Command usage:\n");
+                print_usage();
+                exit(EXIT_SUCCESS);
+                break;
+            case '?':
+                print_usage();
+                exit(EXIT_FAILURE);
+            default:
+                abort();
+        }
+    }
+
+    /// Check for the case that both output file and directory are set
+    if(ofile != NULL && dir != NULL) {
+        printf("Either output file or directory is specified. You cannot use both.\n");
+        print_usage();
+        exit(EXIT_FAILURE);
+    }
+
+    /// Check if the required argument is there
+    if(argv[optind] == NULL) {
+        fprintf(stderr, "Mandatory argument 'url' missing.\n");
+        print_usage();
+        exit(EXIT_FAILURE);
+    } else {
+        url = argv[optind];
+    }
+
+    const char *full_url = strstr(url, "http://") + 7; //< the full url starts after http://
+    const char *path = strstr(full_url, "/");
+}
+
+static void print_usage(void) {
+    printf("client [-p PORT] [ -o FILE | -d DIR ] URL\n");
+}
+
+/**
+ * @brief Function to check the number of arguments
+ * @details Checks the number of arguments supplied to the command line.
+ *          If the arguments are less than the required or more than possible, it exits
+ * @param argc Number of arguments obtained from the command line
+ * @return none
+ *
+ **/
+static void check_opts_number(int argc) {
+    if(argc <= 1) {
+        fprintf(stderr, "At least one argument expected.\n");
+        print_usage();
+        exit(EXIT_FAILURE);
+    } else if(argc > 6) {
+        fprintf(stderr, "Too many arguments supplied.\n");
+        print_usage();
+        exit(EXIT_FAILURE);
+    }
+}

http/shared/http.h

@@ -0,0 +1,7 @@
+#ifndef HTTP_HEADER_FILE
+#define HTTP_HEADER_FILE
+
+static void print_usage();
+static void check_opts_number(int argc);
+
+#endif

mygrep/Makefile

@@ -2,7 +2,7 @@ CC = gcc
 CFLAGS = -std=c99 -pedantic -Wall -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_SVID_SOURCE -D_POSIX_C_SOURCE=200809L -g -c
 TARGET = mygrep
 
-all: $(TARGET).c 
+all: $(TARGET).c
 	$(CC) $(CFLAGS) $(TARGET).c
 	$(CC) $(TARGET).o -o $(TARGET)
 

mygrep/mygrep.c

@@ -1,3 +1,32 @@
+/**
+ * @file mygrep.c
+ * @author Ivaylo Ivanov 11777707
+ * @date 03.11.2018
+ *
+ * @brief Main program module.
+ *
+ * A reduced variation of the Unix-command `grep`.
+ * It reads in several files and prints all lines containing a keyword.
+ *
+ *    SYNOPSIS
+ *    mygrep [-i] [-o outfile] keyword [file...]
+ *
+ * The program `mygrep` reads files line by line and for each line checks whether it contains the search
+ * term keyword. The line is printed if it contains the keyword, otherwise it is not printed.
+ * The program accepts lines of any length.
+ *
+ * If one or multiple input files are specified (given as positional arguments after keyword), then mygrep
+ * reads each of them in the order they are given. If no input file is specified, the program reads from
+ * `stdin`.
+ *
+ * If the option `-o` is given, the output is written to the specified file (outfile). Otherwise, the output is
+ * written to `stdout`.
+ *
+ * If the option `-i` is given, the program does not differentiate between lower and upper case letters, i.e.
+ * the search for the keyword in a line is case insensitive.
+ *
+ **/
+
 #define _GNU_SOURCE ///< in order for strcasestr to work
 #include <stdio.h>
 #include <stdlib.h>
@@ -85,11 +114,11 @@ static void print_usage(void) {
 
 /**
  * @brief Function to check the number of arguments
- * @details Checks the number of arguments supplied to the command line. 
+ * @details Checks the number of arguments supplied to the command line.
  *          If the arguments are less than the required or more than possible, it exits
  * @param argc Number of arguments obtained from the command line
- * @return none 
- * 
+ * @return none
+ *
  **/
 static void check_opts_number(int argc) {
     if(argc <= 1) {
@@ -105,17 +134,17 @@ static void check_opts_number(int argc) {
 
 /**
  * @brief Function to check whether or not a string is contained in another string
- * @details Checks whether or not a substring is contained in a line. 
+ * @details Checks whether or not a substring is contained in a line.
  *          If it is there and no output file is passed, it will print the line to stdout
  *          If it is there and an output file is passed, it will append the line to the end of the output file
- * 
+ *
  * @param
  *      to_check: String to be checked against
  *      to_find: String to search for
  *      iflag: Whether or not to ignore the casing of the letters
  *      ofile: The file to append the output to
  * @return none
- * 
+ *
  **/
 static void check_for_string(char *to_check, char *to_find, int iflag, char *ofile) {
     if(ofile == NULL) {