A simple http server in C

webserver.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <fcntl.h>

#define WEBROOT "./webroot" // the web server's root directory
#define PORT = 8080;

void handle_connection(int, struct sockaddr_in*);
int get_file_size(int);

int main()
{
    int sockfd, clientfd;
    socklen_t cliaddr_len;
    struct sockaddr_in server_addr, client_addr;

    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    if(sockfd == -1)
    {
       printf("Error!");
       exit(1);
    }

    bzero(&server_addr, sizeof(server_addr));

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    int br = bind(sockfd, (struct sockaddr *) &server_addr, sizeof(server_addr));

    if(br == -1)
    {
        printf("Error!");
        exit(1);
    }

    if((listen(sockfd, 20)) == -1)
    {
        printf("Error");
        exit(1);
    }

    while(1)
    {
        clientfd = accept(sockfd, (struct sockaddr *) &client_addr, &cliaddr_len);
        if(clientfd == -1)
        {
            printf("waiting for connection.");
        }
        handle_connection(clientfd, &client_addr);
    }

    return 1;
}

void handle_connection(int sockfd, struct sockaddr_in *client_addr_ptr)
{
    unsigned char *ptr, request[500], resource[500];
    int fd, length;

    length = recv(sockfd, request, 500, 0);

    printf("Got request from %s:%d \"%s\"\n", inet_ntoa(client_addr_ptr->sin_addr), ntohs(client_addr_ptr->sin_port), request);
   
    ptr = strstr(request, " HTTP/");
    if(ptr == NULL)
    {
        printf(" NOT HTTP!\n");
    } else {
        *ptr = 0;
        ptr = NULL;
        if(strncmp(request, "GET ", 4) == 0)
            ptr = request + 4;
        if(strncmp(request, "HEAD ", 5) == 0)
            ptr = request + 5;

        if(ptr == NULL) {
            printf("\tUNKNOWN REQUEST!\n");
        } else {
            if (ptr[strlen(ptr) - 1] == '/')
                strcat(ptr, "index.html");
            strcpy(resource, WEBROOT);
            strcat(resource, ptr);
            fd = open(resource, O_RDONLY, 0);
            printf("\tOpening \'%s\'\t", resource);
            if(fd == -1) {
                printf(" 404 Not Found\n");
                send(sockfd, "HTTP/1.0 404 NOT FOUND\r\n", 24, 0);
            } else {
                printf(" 200 OK\n");
                send(sockfd, "HTTP/1.0 200 OK\r\n", 17, 0);
                send(sockfd, "Server: C\r\n\r\n", 13, 0);
                if(ptr == request + 4) {
                    if( (length = get_file_size(fd)) == -1)
                    {
                        printf("getting resource file size");
                        exit(1);
                    }
                    if( (ptr = (unsigned char *) malloc(length)) == NULL)
                    {
                        printf("allocating memory for reading resource");
                        exit(1);
                    }
                    read(fd, ptr, length);
                    send(sockfd, ptr, length, 0)
                    free(ptr);
            }
            close(fd);
         }
      }
   }
   shutdown(sockfd, SHUT_RDWR);
}

int get_file_size(int fd) {
   struct stat stat_struct;
   if(fstat(fd, &stat_struct) == -1)
      return -1;
   return (int) stat_struct.st_size;
}