Easily create web apps on Windows.

easy-http-server.c

#include <winsock2.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/*///////////////////////////////////
	
		easy-string
		
///////////////////////////////////*/

int indexOf(char* source, char* key, int pos) {
	int i, j, dest;
	
	assert(pos > -1);
		
	for (i=0, j=0, dest=0; i<strlen(source); i++) {
		
		(source[i] == key[j]) ? (j++) : (j=0);
		
		if (j == strlen(key)) {
			j = 0;
			dest = i;
			if (pos == 0) return dest - strlen(key) +1;
			pos--;
		}
	}
	
	return -1;
}

char* substring(char* source, int start, int end) {
	char *dest, *back;
	
	assert(start > -1);
	assert(end > -1);
	assert(start <= end);
	
	dest = malloc(sizeof(char) * strlen(source) +1);
	assert(dest != NULL);
	strcpy(dest, source);
	back = dest;
	
	dest = dest + start;
	*(dest + end - start + 1) = 0;
	
	strcpy(back, dest);
	return back;
}

void toLower(char *string) {
	while (*string++) {
		if (*string > 64 && *string < 91) {
		    *string = tolower(*string);
		}		
	}
}

/*///////////////////////////////////
	
		declaration
		
///////////////////////////////////*/

#ifndef ROUTES_MAX
#define ROUTES_MAX 50
#endif

typedef struct {
	
	char *method;
	char *page;
	char *http_version;
	char *headers;
	char *body;
	SOCKET connected_client;
	char client_ip[20];
	int client_port;
} Request;

struct ROUTES {
	char *page;
	void (*route_function)(Request *r);
} Route[ROUTES_MAX];

size_t route_count = 0;
void (*route_default_pointer)(Request*) = NULL;

void listenTo(char *ip, int port);
void route(char *page, void (*function)(Request *r));
void route_default(void (*function)(Request *r));
void sendTo(Request *r, char *body, char *headers, char *statusline);
void free_request(Request *r);

/*///////////////////////////////////
	
		implementetion
		
///////////////////////////////////*/

void route_default(void (*function)(Request *r)) {
	route_default_pointer = function;
}

void route(char *page, void (*function)(Request *r)) {
	assert(route_count < ROUTES_MAX);
	
	Route[route_count].route_function = function;
	Route[route_count].page = page;
	route_count++;
}

void sendTo(Request *r, char *body, char *headers, char *statusline) {
	size_t content_length;
	char *response;
	
	if (statusline[0] == 0) {
		statusline = "200 OK";
	}
	
	if (headers[0] == 0) {
		headers = "Content-Type: text/html\n"
			  	  "Connection: close\n";
	}
	
	content_length = strlen(body);
	
	response = (char*)malloc(
				  (sizeof(char) * strlen(statusline))
				+ (sizeof(char) * strlen(headers))
				+ (sizeof(char) * strlen(body))
				+ (sizeof(int)) //content-length
				+ 50);
	
	assert(response != NULL);
	
	sprintf(response, "HTTP/1.1 %s\n"
			  "Content-Length: %i\n"
			  "Connection: close\n"
			  "%s\n"
			  "%s", statusline, content_length, headers, body);
	
	if (send(r->connected_client, response, strlen(response), 0) == SOCKET_ERROR ) {
		fprintf(stderr, "Couldn't send data with error %i\n", WSAGetLastError());
	}
	
	free(response);
}

void free_request(Request *r) {
	free(r->body);
	free(r->headers);
	free(r->http_version);
	free(r->page);
	free(r->method);
}

void listenTo(char *ip, int port) {
	WSADATA wsa;
	SOCKET server_socket, client_socket;
	struct sockaddr_in server_addr, client_addr;
	int s, bytes_recieved;
	char request[4096] = {0};
	
	if (WSAStartup(MAKEWORD(2,2), &wsa) != 0) {
		fprintf(stderr, "Couldn't start winsock with error %i\n", WSAGetLastError());
		return;
	}
	
	if ((server_socket = socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) {
		fprintf(stderr, "Couldn't create a socket with error %i\n", WSAGetLastError());
		return;
	}
	
	toLower(ip);
	
	if (strcmp(ip, "localhost") == 0)
		server_addr.sin_addr.s_addr = INADDR_ANY;
	else
		server_addr.sin_addr.s_addr = inet_addr(ip);
	
	server_addr.sin_family = AF_INET;
	server_addr.sin_port = htons(port);
	
	if (bind(server_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) == SOCKET_ERROR) {
		fprintf(stderr, "Couldn't bind ip to socket with error %i\n", WSAGetLastError());
		return;
	}
	
	if (listen(server_socket, SOMAXCONN) == SOCKET_ERROR) {
		fprintf(stderr, "Couldn't made the socket listen with error %i\n", WSAGetLastError());
		return;
	}
	
	s = sizeof(client_addr);
	while ((client_socket = accept(server_socket, (struct sockaddr*)&client_addr, &s)) != INVALID_SOCKET) {
		
		memset(request, 0, sizeof(request));
		bytes_recieved = recv(client_socket, request, sizeof(request)-1, 0);
		
		if (bytes_recieved == SOCKET_ERROR) {
			fprintf(stderr, "Couldn't completely received request with error %i\n", WSAGetLastError());
			closesocket(client_socket);
			continue;
		}
		
		if (bytes_recieved == 0) {
			fprintf(stderr, "Connection successfully closed\n");
			continue;
		}
		
		Request r;
		
		//getting method
		if (indexOf(request, " ", 0) != -1) {
			r.method = substring(request, 0, indexOf(request, " ", 0)-1);
		}
		
		//getting resource
		if (indexOf(request, " ", 1) != -1) {
			r.page = substring(request, indexOf(request, " ", 0)+1,
							   indexOf(request, " ", 1)-1);
		}
		
		//getting http version
		if (indexOf(request, "\n", 0) != -1) {
			r.http_version = substring(request, indexOf(request, " ", 1)+1,
									   indexOf(request, "\n", 0)-1);
		}
		
		//getting headers
		if (indexOf(request, "\n\r", 0) != -1) {
			r.headers = substring(request, indexOf(request, "\n", 0)+1,
								  indexOf(request, "\n\r", 0)-2);
		}
		
		//getting body
		r.body = substring(request, indexOf(request, "\n\r", 0)+2,
									strlen(request)-1);
		
		//setting client info
		r.connected_client = client_socket;
		r.client_port = htons(client_addr.sin_port);
		strncpy(r.client_ip, inet_ntoa(client_addr.sin_addr), 19);
		
		int i;
		for (i=0; i<route_count; i++)
			if (strcmp(Route[i].page, r.page) == 0) {
				Route[i].route_function(&r);
				break;
			}
		
		if (i >= route_count && route_default_pointer != NULL) route_default_pointer(&r);
		
		free_request(&r);
		closesocket(client_socket);
	}
	
	WSACleanup();
}
/*///////////////////////////////////
	
		testing
		
///////////////////////////////////*/

void index_page(Request *r) {
	printf("Connected to %s:%i\n", r->client_ip, r->client_port);
	printf("%s %s %s\n%s\n%s\n\n", r->method, r->page, r->http_version,
			r->headers, r->body);
			
	sendTo(r, "Hello, World!", "", "");
}

void foo(Request *r) {
	sendTo(r, "<!DOCTYPE html><html><head><title>"
		  "404 Not Found</title></head><body>"
		  "<h1>Not Found</h1>The requested URL was not found"
	          " on this server.</body></html>", "", "404 NOT FOUND");

}

int main() {
	route_default(foo);
	route("/", index_page);
	listenTo("localhost", 80);
	
	return 0;
}