ℹ️ New Book: Build Your Own Database
redis/03/03_server.cpp
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/ip.h>
static void msg(const char *msg) {
fprintf(stderr, "%s\n", msg);
}
static void die(const char *msg) {
int err = errno;
fprintf(stderr, "[%d] %s\n", err, msg);
abort();
}
static void do_something(int connfd) {
char rbuf[64] = {};
ssize_t n = read(connfd, rbuf, sizeof(rbuf) - 1);
if (n < 0) {
msg("read() error");
return;
}
printf("client says: %s\n", rbuf);
char wbuf[] = "world";
write(connfd, wbuf, strlen(wbuf));
}
int main() {
int fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
die("socket()");
}
// this is needed for most server applications
int val = 1;
setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
// bind
struct sockaddr_in addr = {};
addr.sin_family = AF_INET;
addr.sin_port = ntohs(1234);
addr.sin_addr.s_addr = ntohl(0); // wildcard address 0.0.0.0
int rv = bind(fd, (const sockaddr *)&addr, sizeof(addr));
if (rv) {
die("bind()");
}
// listen
rv = listen(fd, SOMAXCONN);
if (rv) {
die("listen()");
}
while (true) {
// accept
struct sockaddr_in client_addr = {};
socklen_t socklen = sizeof(client_addr);
int connfd = accept(fd, (struct sockaddr *)&client_addr, &socklen);
if (connfd < 0) {
continue; // error
}
do_something(connfd);
close(connfd);
}
return 0;
}
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codecrafters.io offers “Build Your Own X” courses in many programming languages.
Including Redis, Git, SQLite, Docker, and more.
Check it out
codecrafters.io offers “Build Your Own X” courses in many programming languages.
Including Redis, Git, SQLite, Docker, and more.