ryankearney/reddit.c

## reddit.c
#include <stdio.h>
#include <time.h>
#include <netinet/in.h>
typedef struct {
	int ID;
	char * title;
	char * link;
	char * date;
	int upVotes;
	int downVotes;
	void * next;
} Article;

Article * root;

char * getVal(char * query, char * key) {
	char * str = malloc(1);
	int match = 0;
	int pMatch = 0;
	char * cur = query;

	while (*cur != '\0') {
		if (pMatch >= 1 && (*cur == '&' || *cur == '\n' || *cur == ' ')) {
			break;
		} else if (pMatch >= 1) {
			str = realloc(str, pMatch+1);
			*(str+pMatch-1) = *cur; ++pMatch;
		} else if (match == strlen(key)) {
			pMatch = 1;
		} else if (*cur == key[match]) {
			++match;
		} else {
			match = 0;
		}
		cur++;
	}
	if (pMatch >= 1) {
		str[pMatch-1] = '\0';
		return str;
	}
	free(str);
	return NULL;
}

char from_hex(char ch) {
	return isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10;
}

char to_hex(char code) {
	static char hex[] = "0123456789abcdef";
	return hex[code & 15];
}

char *url_decode(char *str) {
	char *pstr = str, *buf = malloc(strlen(str) + 1), *pbuf = buf;
	while (*pstr) {
		if (*pstr == '%') {
			if (pstr[1] && pstr[2]) {
				*pbuf++ = from_hex(pstr[1]) << 4 | from_hex(pstr[2]);
				pstr += 2;
			}
		} else if (*pstr == '+') {
			*pbuf++ = ' ';
		} else {
			*pbuf++ = *pstr;
		}
		pstr++;
	}
	*pbuf = '\0';
	return buf;
}

void send_headers(FILE *f, int status, char *title, char *extra, char *mime, int length) {
	char timebuf[128];
	fprintf(f, "%s %d %s\r\n", "HTTP/1.0", status, title);
	fprintf(f, "Server: %s\r\n", "redditserver/1.0");
	if (extra) fprintf(f, "%s\r\n", extra);
	if (mime) fprintf(f, "Content-Type: %s\r\n", mime);
	if (length >= 0) fprintf(f, "Content-Length: %d\r\n", length);
	fprintf(f, "Connection: close\r\n");
	fprintf(f, "\r\n");
}

void reddit(FILE *f) {
	fprintf(f, "<HTML><HEAD><TITLE>Reddit Clone</TITLE></HEAD>\r\n");

	fprintf(f, "\
<BODY><H1>Submit</H1><form action=\"/\" method=\"get\">Title:<input type=\"text\" \
name=\"title\" /> Link:<input type=\"text\" name=\"link\" /><input type=\"submit\" \
value=\"Submit\" /></form>\r\n");

	if (root) {
		fprintf(f, "<h1>Articles</h1>");
		Article * cur = root;
		while (cur != NULL) {
			fprintf(f, "\
<p><font size=\"5\">%d<b><a href=\"/?up=%d\">&uarr</b></font><a href=\"%s\">%s</a>\
<br /><font size=\"5\">&nbsp;&nbsp;<b><a href=\"/?down=%d\">&darr</a></b>\
</font>%s -- %s</p>", cur->upVotes - cur->downVotes, cur->ID, cur->link, cur->title,
cur->ID, cur->link, cur->date);

		cur = cur->next;
		}
	}
	fprintf(f, "</BODY></HTML>\r\n");
}


int fsize(FILE * f) {
	fseek(f, 0, SEEK_END);
	int size = ftell(f);
	fseek(f, 0, SEEK_SET);
	return size;
}

int main(int argc, char *argv[]) {
	int sock;
	int port = 1337;
	struct sockaddr_in sin;
	sock = socket(AF_INET, SOCK_STREAM, 0);
	sin.sin_family = AF_INET;
	sin.sin_addr.s_addr = INADDR_ANY;
	sin.sin_port = htons(port);
	while (bind(sock, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
		printf("Failed bind\n"); sleep(2);
	}
	listen(sock, 5);
	printf("HTTP server listening on port %d\n", port);
	root = NULL;
	while (1) {
		int s;
		int size;
		int hsize;
		char * buff;
		FILE * t;
		FILE * ht;
		FILE * f;
		s = accept(sock, NULL, NULL);
		if (s < 0) break;
		char * header = calloc(255, 1);
		size = read(s, header, 255);
		char * titleEnc = getVal(header, "title");
		char * linkEnc = getVal(header, "link");
		if (titleEnc && linkEnc) {
			char * title = url_decode(titleEnc);
			char * link =  url_decode(linkEnc);
			free(linkEnc);
			free(titleEnc);
			printf("Title: %s -- Link: %s\n", title, link);
			char  * s = malloc(30);
			size_t i;
			struct tm tim;
			time_t now;
			now = time(NULL);
			tim = *(localtime(&now));
			i = strftime(s,30,"%b %d, %Y; %H:%M:%S\n",&tim);
			Article * new = malloc(sizeof(Article));
			new->title = title;
			new->link = link;
			new->next = NULL;
			new->date = s;
			new->upVotes = 0;
			new->downVotes = 0;
			if (!root) {
				root = new;
				new->ID = 0;
			} else {
				int dupe = 0;
				Article * cur = root;
				Article * prev = NULL;
				while (cur != NULL) {
					if (strcmp(cur->title, new->title) == 0 || strcmp(cur->link, new->link) == 0) {
						dupe = 1;
					}
					prev = cur;
					cur = cur->next;
				}
				if (dupe == 0) {
					new->ID = prev->ID + 1;
					prev->next = new;
				} else free(new);
			}
		}
		char * upID = getVal(header, "up");
		if (upID) {
			int ID = atoi(upID);
			Article * cur = root;
			while (cur != NULL) {
				if (cur->ID == ID) {
					cur->upVotes++; break;
				}
				cur = cur->next;
			}
		}
		char * dID = getVal(header, "down");
		if (dID) {
			int ID = atoi(dID);
			Article * cur = root;
			while (cur != NULL) {
				if (cur->ID == ID) {
					cur->downVotes++;
					break;
				}
				cur = cur->next;
			}
		}
		t = tmpfile();
		ht = tmpfile();
		reddit(t);
		size = fsize(t);
		send_headers(ht, 200, "Ok", NULL, "text/html", size);
		hsize = fsize(ht);
		buff = malloc(hsize);
		fread(buff, 1, hsize, ht);
		write(s,buff,hsize);
		free(buff);
		buff = malloc(size);
		fread(buff, 1, size, t);
		write(s,buff,size);
		free(buff);
		fclose(t);
	}
}
	#include <stdio.h>
	#include <time.h>
	#include <netinet/in.h>
	typedef struct {
	int ID;
	char * title;
	char * link;
	char * date;
	int upVotes;
	int downVotes;
	void * next;
	} Article;

	Article * root;

	char * getVal(char * query, char * key) {
	char * str = malloc(1);
	int match = 0;
	int pMatch = 0;
	char * cur = query;

	while (*cur != '\0') {
	if (pMatch >= 1 && (cur == '&' \|\| cur == '\n' \|\| *cur == ' ')) {
	break;
	} else if (pMatch >= 1) {
	str = realloc(str, pMatch+1);
	(str+pMatch-1) = cur; ++pMatch;
	} else if (match == strlen(key)) {
	pMatch = 1;
	} else if (*cur == key[match]) {
	++match;
	} else {
	match = 0;
	}
	cur++;
	}
	if (pMatch >= 1) {
	str[pMatch-1] = '\0';
	return str;
	}
	free(str);
	return NULL;
	}

	char from_hex(char ch) {
	return isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10;
	}

	char to_hex(char code) {
	static char hex[] = "0123456789abcdef";
	return hex[code & 15];
	}

	char url_decode(char str) {
	char pstr = str, buf = malloc(strlen(str) + 1), *pbuf = buf;
	while (*pstr) {
	if (*pstr == '%') {
	if (pstr[1] && pstr[2]) {
	*pbuf++ = from_hex(pstr[1]) << 4 \| from_hex(pstr[2]);
	pstr += 2;
	}
	} else if (*pstr == '+') {
	*pbuf++ = ' ';
	} else {
	pbuf++ = pstr;
	}
	pstr++;
	}
	*pbuf = '\0';
	return buf;
	}

	void send_headers(FILE f, int status, char title, char extra, char mime, int length) {
	char timebuf[128];
	fprintf(f, "%s %d %s\r\n", "HTTP/1.0", status, title);
	fprintf(f, "Server: %s\r\n", "redditserver/1.0");
	if (extra) fprintf(f, "%s\r\n", extra);
	if (mime) fprintf(f, "Content-Type: %s\r\n", mime);
	if (length >= 0) fprintf(f, "Content-Length: %d\r\n", length);
	fprintf(f, "Connection: close\r\n");
	fprintf(f, "\r\n");
	}

	void reddit(FILE *f) {
	fprintf(f, "<HTML><HEAD><TITLE>Reddit Clone</TITLE></HEAD>\r\n");

	fprintf(f, "\
	<BODY><H1>Submit</H1><form action=\"/\" method=\"get\">Title:<input type=\"text\" \
	name=\"title\" /> Link:<input type=\"text\" name=\"link\" /><input type=\"submit\" \
	value=\"Submit\" /></form>\r\n");

	if (root) {
	fprintf(f, "<h1>Articles</h1>");
	Article * cur = root;
	while (cur != NULL) {
	fprintf(f, "\
	<p><font size=\"5\">%d<b><a href=\"/?up=%d\">&uarr</b></font><a href=\"%s\">%s</a>\
	<br /><font size=\"5\">  <b><a href=\"/?down=%d\">&darr</a></b>\
	</font>%s -- %s</p>", cur->upVotes - cur->downVotes, cur->ID, cur->link, cur->title,
	cur->ID, cur->link, cur->date);

	cur = cur->next;
	}
	}
	fprintf(f, "</BODY></HTML>\r\n");
	}


	int fsize(FILE * f) {
	fseek(f, 0, SEEK_END);
	int size = ftell(f);
	fseek(f, 0, SEEK_SET);
	return size;
	}

	int main(int argc, char *argv[]) {
	int sock;
	int port = 1337;
	struct sockaddr_in sin;
	sock = socket(AF_INET, SOCK_STREAM, 0);
	sin.sin_family = AF_INET;
	sin.sin_addr.s_addr = INADDR_ANY;
	sin.sin_port = htons(port);
	while (bind(sock, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
	printf("Failed bind\n"); sleep(2);
	}
	listen(sock, 5);
	printf("HTTP server listening on port %d\n", port);
	root = NULL;
	while (1) {
	int s;
	int size;
	int hsize;
	char * buff;
	FILE * t;
	FILE * ht;
	FILE * f;
	s = accept(sock, NULL, NULL);
	if (s < 0) break;
	char * header = calloc(255, 1);
	size = read(s, header, 255);
	char * titleEnc = getVal(header, "title");
	char * linkEnc = getVal(header, "link");
	if (titleEnc && linkEnc) {
	char * title = url_decode(titleEnc);
	char * link = url_decode(linkEnc);
	free(linkEnc);
	free(titleEnc);
	printf("Title: %s -- Link: %s\n", title, link);
	char * s = malloc(30);
	size_t i;
	struct tm tim;
	time_t now;
	now = time(NULL);
	tim = *(localtime(&now));
	i = strftime(s,30,"%b %d, %Y; %H:%M:%S\n",&tim);
	Article * new = malloc(sizeof(Article));
	new->title = title;
	new->link = link;
	new->next = NULL;
	new->date = s;
	new->upVotes = 0;
	new->downVotes = 0;
	if (!root) {
	root = new;
	new->ID = 0;
	} else {
	int dupe = 0;
	Article * cur = root;
	Article * prev = NULL;
	while (cur != NULL) {
	if (strcmp(cur->title, new->title) == 0 \|\| strcmp(cur->link, new->link) == 0) {
	dupe = 1;
	}
	prev = cur;
	cur = cur->next;
	}
	if (dupe == 0) {
	new->ID = prev->ID + 1;
	prev->next = new;
	} else free(new);
	}
	}
	char * upID = getVal(header, "up");
	if (upID) {
	int ID = atoi(upID);
	Article * cur = root;
	while (cur != NULL) {
	if (cur->ID == ID) {
	cur->upVotes++; break;
	}
	cur = cur->next;
	}
	}
	char * dID = getVal(header, "down");
	if (dID) {
	int ID = atoi(dID);
	Article * cur = root;
	while (cur != NULL) {
	if (cur->ID == ID) {
	cur->downVotes++;
	break;
	}
	cur = cur->next;
	}
	}
	t = tmpfile();
	ht = tmpfile();
	reddit(t);
	size = fsize(t);
	send_headers(ht, 200, "Ok", NULL, "text/html", size);
	hsize = fsize(ht);
	buff = malloc(hsize);
	fread(buff, 1, hsize, ht);
	write(s,buff,hsize);
	free(buff);
	buff = malloc(size);
	fread(buff, 1, size, t);
	write(s,buff,size);
	free(buff);
	fclose(t);
	}
	}