Add initial server functionality and clean up

http/README.md

@@ -15,6 +15,11 @@ the URL. The transmitted content of that file is written to `stdout`, to a file
 
 ## server
 
-Not implemented yet
+The server takes a document root as input, reads it and serves it on the port specified(`8080` by default). If the `-i` flag is specified, the server uses its value as an index file. If not, it takes index.html as a default. The server supports **ONLY** GET requests. If it receives another request type it will return a response status **501** (Not implemented). If the file requested is not found, the server returns a response status **404** (Not found).
+
+    SYNOPSIS
+    server [-p PORT] [-i INDEX] DOC_ROOT
+    EXAMPLE
+    server -p 1280 -i index.html ./public/
 
 **Note: The description is from the task I got from TU.**

http/client.c

@@ -56,7 +56,6 @@ int main(int argc, char *argv[]) {
                 printf("Command usage:\n");
                 print_usage();
                 exit(EXIT_SUCCESS);
-                break;
             case '?':
                 print_usage();
                 exit(EXIT_FAILURE);
@@ -116,6 +115,8 @@ int main(int argc, char *argv[]) {
     process_response(reply, ofile, dir);
 
     freeaddrinfo(config); //< Free the addrinfo struct
+
+    exit(EXIT_SUCCESS); //< Exit with success
 }
 
 static void print_usage(void) {
@@ -177,7 +178,7 @@ static struct addrinfo* get_host_info(const char *hostname, char *port) {
 }
 
 /**
- * @brief Function to create a socker using the supplied configuration
+ * @brief Function to create a socket using the supplied configuration
  * @details Creates a socket using the supplied configuration
  *          If there was no error, it returns the socket
  *          If there was an error, it exits and displays an error message
@@ -219,9 +220,7 @@ static void process_response(char reply[sizeof(int32_t)], char *ofile, char *dir
             exit(EXIT_FAILURE);
         } else if (response_code != 200) {
             printf("%s\n", strtok(reply, "\r\n")); //< Get the first line
-            exit(EXIT_SUCCESS);
+        } else {
-        }
-
             char *body = strstr(reply, "\r\n\r\n") + 4;
             if(ofile == NULL && dir == NULL) printf("%s", body); //< Print the body of the response
             else {
@@ -236,7 +235,6 @@ static void process_response(char reply[sizeof(int32_t)], char *ofile, char *dir
                         fprintf(out, "%s", body);
                         fclose(out);
                         printf("File ./%s successfully written.\n", ofile);
-                    exit(EXIT_SUCCESS);
                     }
                 } else if(dir != NULL) {
                     FILE *out = NULL;
@@ -263,12 +261,10 @@ static void process_response(char reply[sizeof(int32_t)], char *ofile, char *dir
                             printf("File %sresult.html successfully written.\n", dir);
                         else
                             printf("File %s/result.html successfully written.\n", dir);
-
-                    exit(EXIT_SUCCESS);
                     }
                 }
             }
-
+        }
     } else {
         fprintf(stderr, "ERROR: Protocol error.\n");
         exit(EXIT_FAILURE);

http/server.c

@@ -0,0 +1,223 @@
+#define _GNU_SOURCE ///< in order for optarg to be defined
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include "shared/http.h"
+
+#define LISTEN_BACKLOG 5 //< Define maximum size of the input queue
+
+static int create_server_socket(uint16_t port, struct sockaddr_in incoming);
+static char * get_file_contents(char *dir, char *file);
+
+int main(int argc, char *argv[]) {
+    check_opts_number(argc);
+
+    char *cport = "8080";
+    char *ifile = "index.html";
+    char *dir = NULL;
+    char response[sizeof(int32_t)]; //< To hold the server response
+    int c;
+
+    /// Process the options
+    while((c = getopt(argc, argv, "p:i:h")) != -1) {
+        switch(c) {
+            case 'p':
+                cport = optarg;
+                break;
+            case 'i':
+                ifile = optarg;
+                break;
+            case 'h':
+                printf("Command usage:\n");
+                print_usage();
+                exit(EXIT_SUCCESS);
+            case '?':
+                print_usage();
+                exit(EXIT_FAILURE);
+            default:
+                abort();
+        }
+    }
+
+    /// Check if the required argument is there
+    if(argv[optind] == NULL) {
+        fprintf(stderr, "Mandatory argument 'doc_root' missing.\n");
+        print_usage();
+        exit(EXIT_FAILURE);
+    } else {
+        dir = argv[optind];
+    }
+
+    uint16_t port = atoi(cport); //< Convert the argument to integer
+
+    struct sockaddr_in incoming; //< Basic incoming config
+
+    incoming.sin_addr.s_addr = INADDR_ANY; //< Allow 0.0.0.0 to access the server
+	incoming.sin_port = htons(port); //< Set the port to work on
+	incoming.sin_family = AF_INET; //< Use IPv4
+
+    int sockfd = create_server_socket(port, incoming); //< Define a server socket
+
+    socklen_t peer_addr_size = sizeof(struct sockaddr_in);
+
+    /// Start accepting connections
+    int current_session = accept(sockfd, (struct sockaddr*) &incoming, &peer_addr_size); //< Save the current session
+
+    if(current_session < 0) {
+        (void) fprintf(stderr, "ERROR: Could not start accepting connections\n");
+        close(sockfd);
+		exit(EXIT_FAILURE);
+    } else {
+        char request[sizeof(int32_t)];
+
+        if(recv(current_session, request, strlen(request) - 1, 0) < 0) {
+            (void) fprintf(stderr, "ERROR: Could not receive connection from client\n");
+            close(current_session);
+            close(sockfd);
+            exit(EXIT_FAILURE);
+        } else {
+            char method[4];
+            strncpy(method, request, 4); //< Get the request type
+            method[3] = 0; //< Add terminating char
+
+            if(strcmp(method, "GET") == 0) {
+                (void) fprintf(stdout, "Got here\n");
+                close(current_session);
+                close(sockfd);
+            } else {
+                fprintf(stderr, "ERROR: Unhandled HTTP request method received\n");
+                char header[sizeof(int8_t) + 100];
+                time_t t = time(NULL);
+                struct tm tm = *localtime(&t);
+                snprintf(
+                    header,
+                    sizeof header,
+                    "HTTP/1.1 501 Not Implemented\r\nDate: %d, %d %d %d %d:%d:%d %s\r\nContent-Length: 0\r\nConnection: close\r\n\r\n",
+                    tm.tm_wday, tm.tm_mday, tm.tm_mon, tm.tm_year + 1900, tm.tm_hour, tm.tm_min, tm.tm_sec, tm.tm_zone
+                ); //< Build the header
+
+                puts(header);
+                strncpy(response, header, sizeof(header));
+            }
+            close(current_session);
+            close(sockfd);
+        }
+    }
+
+    /// Send the response to the client
+    if(send(current_session, response, strlen(response) + 1, 0) < 0) {
+        (void) fprintf(stderr, "ERROR: Could not send the response to the client\n");
+        close(current_session);
+        close(sockfd);
+        exit(EXIT_FAILURE);
+    }
+
+    close(current_session);
+    close(sockfd);
+    exit(EXIT_SUCCESS);
+}
+
+static void print_usage(void) {
+    printf("server [-p PORT] [ -i INDEX ] DOC_ROOT\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);
+    }
+}
+
+/**
+ * @brief Function to create a socket using a default configuration for a server
+ * @details Creates a socket using a default configuration for a server
+ *          If there was no error, it returns the socket
+ *          If there was an error, it exits and displays an error message
+ * @param port     - the port to bind the server to
+ *        incoming - basic incoming sockaddr config
+ * @return sockfd - The socket obtained from the socket creation
+ **/
+static int create_server_socket(uint16_t port, struct sockaddr_in incoming) {
+    int sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); //< Define socket with default configuration
+
+    if(sockfd < 0) {
+		(void) fprintf(stderr, "ERROR: Socket creation failed.\n");
+		exit(EXIT_FAILURE);
+	}
+
+    /// Bind to a port
+    if(bind(sockfd, (struct sockaddr*) &incoming, sizeof(struct sockaddr_in)) < 0) {
+		(void) fprintf(stderr, "ERROR: Could not bind server to port %d!\n", port);
+		close(sockfd);
+		exit(EXIT_FAILURE);
+	}
+
+    /// Start listening on the socket
+	if(listen(sockfd, LISTEN_BACKLOG) < 0)
+	{
+		(void) fprintf(stderr, "ERROR: Could not start listening\n");
+		close(sockfd);
+		exit(EXIT_FAILURE);
+	} else {
+        (void) fprintf(stdout, "Listening on port %d...\n", port);
+    }
+
+    return sockfd;
+}
+
+/**
+ * @brief Function to take the contents of a specified file
+ * @details Gets the contents of the file specified
+ *          If there is no file, it returns NULL
+ *          If the file is empty, it returns " "
+ *          If the file is not empty, it returns its contents
+ * @param dir      - the directory of the file
+ *        filename - the name of the file
+ * @return res - The contents of the file, formatted as a string
+ **/
+static char * get_file_contents(char *dir, char *filename) {
+    char *path = strcpy(dir, filename);
+
+    FILE *file = NULL;
+
+    file = fopen(path, "r");
+
+    if(file == NULL) {
+        return NULL;
+    } else {
+        char *res = 0;
+
+        fseek(file, 0, SEEK_END); //< Set position to end of stream
+        int file_length = ftell(file); //< Get file length
+        fseek(file, 0, SEEK_SET); //< Set the position to begining of stream
+        res = malloc(file_length); //< Allocate memory for the file contents
+
+        if(res != 0) {
+            fread(res, 1, file_length, file); //< Read the contents into res
+        } else {
+            return " ";
+        }
+
+        return res;
+    }
+}

mygrep/mygrep.c

@@ -59,7 +59,6 @@ int main(int argc, char *argv[]) {
                 printf("Command usage:\n");
                 print_usage();
                 exit(EXIT_SUCCESS);
-                break;
             case '?':
                 print_usage();
                 exit(EXIT_FAILURE);