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#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <pthread.h>
#include "urweb.h"
int lw_port = 8080;
int lw_backlog = 10;
int lw_bufsize = 1024;
typedef struct node {
int fd;
struct node *next;
} *node;
static node front = NULL, back = NULL;
static int empty() {
return front == NULL;
}
static void enqueue(int fd) {
node n = malloc(sizeof(struct node));
n->fd = fd;
n->next = NULL;
if (back)
back->next = n;
else
front = n;
back = n;
}
static int dequeue() {
int ret = front->fd;
front = front->next;
if (!front)
back = NULL;
return ret;
}
static pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t queue_cond = PTHREAD_COND_INITIALIZER;
#define MAX_RETRIES 5
static void *worker(void *data) {
int me = *(int *)data;
lw_context ctx = lw_init(1024, 1024);
while (1) {
char buf[lw_bufsize+1], *back = buf, *s;
int sock;
pthread_mutex_lock(&queue_mutex);
while (empty())
pthread_cond_wait(&queue_cond, &queue_mutex);
sock = dequeue();
pthread_mutex_unlock(&queue_mutex);
printf("Handling connection with thread #%d.\n", me);
while (1) {
unsigned retries_left = MAX_RETRIES;
int r = recv(sock, back, lw_bufsize - (back - buf), 0);
if (r < 0) {
fprintf(stderr, "Recv failed\n");
break;
}
if (r == 0) {
printf("Connection closed.\n");
break;
}
printf("Received %d bytes.\n", r);
back += r;
*back = 0;
if (s = strstr(buf, "\r\n\r\n")) {
char *cmd, *path, *inputs;
*s = 0;
printf("Read: %s\n", buf);
if (!(s = strstr(buf, "\r\n"))) {
fprintf(stderr, "No newline in buf\n");
break;
}
*s = 0;
cmd = s = buf;
if (!strsep(&s, " ")) {
fprintf(stderr, "No first space in HTTP command\n");
break;
}
if (strcmp(cmd, "GET")) {
fprintf(stderr, "Not ready for non-get command: %s\n", cmd);
break;
}
path = s;
if (!strsep(&s, " ")) {
fprintf(stderr, "No second space in HTTP command\n");
break;
}
if (inputs = strchr(path, '?')) {
char *name, *value;
*inputs++ = 0;
while (*inputs) {
name = inputs;
if (inputs = strchr(inputs, '&'))
*inputs++ = 0;
else
inputs = strchr(name, 0);
if (value = strchr(name, '=')) {
*value++ = 0;
lw_set_input(ctx, name, value);
}
else
lw_set_input(ctx, name, "");
}
}
printf("Serving URI %s....\n", path);
while (1) {
failure_kind fk;
lw_write(ctx, "HTTP/1.1 200 OK\r\n");
lw_write(ctx, "Content-type: text/html\r\n\r\n");
lw_write(ctx, "<html>");
fk = lw_begin(ctx, path);
if (fk == SUCCESS) {
lw_write(ctx, "</html>");
break;
} else if (fk == BOUNDED_RETRY) {
if (retries_left) {
printf("Error triggers bounded retry: %s\n", lw_error_message(ctx));
--retries_left;
}
else {
printf("Fatal error (out of retries): %s\n", lw_error_message(ctx));
lw_reset_keep_error_message(ctx);
lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r");
lw_write(ctx, "Content-type: text/plain\r\n\r\n");
lw_write(ctx, "Fatal error (out of retries): ");
lw_write(ctx, lw_error_message(ctx));
lw_write(ctx, "\n");
}
} else if (fk == UNLIMITED_RETRY)
printf("Error triggers unlimited retry: %s\n", lw_error_message(ctx));
else if (fk == FATAL) {
printf("Fatal error: %s\n", lw_error_message(ctx));
lw_reset_keep_error_message(ctx);
lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r");
lw_write(ctx, "Content-type: text/plain\r\n\r\n");
lw_write(ctx, "Fatal error: ");
lw_write(ctx, lw_error_message(ctx));
lw_write(ctx, "\n");
break;
} else {
printf("Unknown lw_handle return code!\n");
lw_reset_keep_request(ctx);
lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r");
lw_write(ctx, "Content-type: text/plain\r\n\r\n");
lw_write(ctx, "Unknown lw_handle return code!\n");
break;
}
lw_reset_keep_request(ctx);
}
lw_send(ctx, sock);
printf("Done with client.\n\n");
break;
}
}
close(sock);
lw_reset(ctx);
}
}
int main(int argc, char *argv[]) {
// The skeleton for this function comes from Beej's sockets tutorial.
int sockfd; // listen on sock_fd
struct sockaddr_in my_addr;
struct sockaddr_in their_addr; // connector's address information
int sin_size, yes = 1;
int nthreads, i, *names;
if (argc < 2) {
fprintf(stderr, "No thread count specified\n");
return 1;
}
nthreads = atoi(argv[1]);
if (nthreads <= 0) {
fprintf(stderr, "Invalid thread count\n");
return 1;
}
names = calloc(nthreads, sizeof(int));
sockfd = socket(PF_INET, SOCK_STREAM, 0); // do some error checking!
if (sockfd < 0) {
fprintf(stderr, "Listener socket creation failed\n");
return 1;
}
if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) < 0) {
fprintf(stderr, "Listener socket option setting failed\n");
return 1;
}
my_addr.sin_family = AF_INET; // host byte order
my_addr.sin_port = htons(lw_port); // short, network byte order
my_addr.sin_addr.s_addr = INADDR_ANY; // auto-fill with my IP
memset(my_addr.sin_zero, '\0', sizeof my_addr.sin_zero);
if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof my_addr) < 0) {
fprintf(stderr, "Listener socket bind failed\n");
return 1;
}
if (listen(sockfd, lw_backlog) < 0) {
fprintf(stderr, "Socket listen failed\n");
return 1;
}
sin_size = sizeof their_addr;
printf("Listening on port %d....\n", lw_port);
for (i = 0; i < nthreads; ++i) {
pthread_t thread;
names[i] = i;
if (pthread_create(&thread, NULL, worker, &names[i])) {
fprintf(stderr, "Error creating worker thread #%d\n", i);
return 1;
}
}
while (1) {
int new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size);
if (new_fd < 0) {
fprintf(stderr, "Socket accept failed\n");
return 1;
}
printf("Accepted connection.\n");
pthread_mutex_lock(&queue_mutex);
enqueue(new_fd);
pthread_cond_broadcast(&queue_cond);
pthread_mutex_unlock(&queue_mutex);
}
}
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