From b8b69255e347eb9001f94236ea21384ea04b6099 Mon Sep 17 00:00:00 2001
From: "K. Lange" <klange@toaruos.org>
Date: Tue, 18 Apr 2023 19:38:25 +0900
Subject: [PATCH] net: Support ioctl FIONBIO to set non-blocking

---
 base/usr/include/kernel/net/netif.h |  1 +
 base/usr/include/sys/ioctl.h        |  1 +
 kernel/net/ipv4.c                   |  6 ++++++
 kernel/net/socket.c                 | 13 +++++++++++++
 4 files changed, 21 insertions(+)

diff --git a/base/usr/include/kernel/net/netif.h b/base/usr/include/kernel/net/netif.h
index 9393214a..8ddfc12c 100644
--- a/base/usr/include/kernel/net/netif.h
+++ b/base/usr/include/kernel/net/netif.h
@@ -35,6 +35,7 @@ typedef struct SockData {
 
 	size_t unread;
 	char * buf;
+	int nonblocking;
 } sock_t;
 
 void net_sock_alert(sock_t * sock);
diff --git a/base/usr/include/sys/ioctl.h b/base/usr/include/sys/ioctl.h
index 65f8b35b..d51ab55e 100644
--- a/base/usr/include/sys/ioctl.h
+++ b/base/usr/include/sys/ioctl.h
@@ -14,4 +14,5 @@
 
 #define IOCTL_PACKETFS_QUEUED 0x5050
 
+#define FIONBIO  0x4e424c4b
 
diff --git a/kernel/net/ipv4.c b/kernel/net/ipv4.c
index 3721613b..fe4ad8de 100644
--- a/kernel/net/ipv4.c
+++ b/kernel/net/ipv4.c
@@ -207,6 +207,8 @@ static long sock_icmp_recv(sock_t * sock, struct msghdr * msg, int flags) {
 	}
 	if (msg->msg_iovlen == 0) return 0;
 
+	if (!sock->rx_queue->length && sock->nonblocking) return -EAGAIN;
+
 	char * packet = net_sock_get(sock);
 	if (!packet) return -EINTR;
 	size_t packet_size = *(size_t*)packet - sizeof(struct ipv4_packet);
@@ -536,6 +538,8 @@ static long sock_udp_recv(sock_t * sock, struct msghdr * msg, int flags) {
 	}
 	if (msg->msg_iovlen == 0) return 0;
 
+	if (!sock->rx_queue->length && sock->nonblocking) return -EAGAIN;
+
 	char * packet = net_sock_get(sock);
 	if (!packet) return -EINTR;
 	struct ipv4_packet * data = (struct ipv4_packet*)(packet + sizeof(size_t));
@@ -698,6 +702,8 @@ static long sock_tcp_recv(sock_t * sock, struct msghdr * msg, int flags) {
 		return 0; /* EOF */
 	}
 
+	if (!sock->rx_queue->length && sock->nonblocking) return -EAGAIN;
+
 	while (!sock->rx_queue->length) {
 		process_wait_nodes((process_t *)this_core->current_process, (fs_node_t*[]){(fs_node_t*)sock,NULL}, 200);
 	}
diff --git a/kernel/net/socket.c b/kernel/net/socket.c
index ff65de69..fe55d3e8 100644
--- a/kernel/net/socket.c
+++ b/kernel/net/socket.c
@@ -105,6 +105,18 @@ void sock_generic_close(fs_node_t *node) {
 	printf("net: socket closed\n");
 }
 
+int sock_generic_ioctl(fs_node_t * node, unsigned long request, void * argp) {
+	sock_t * sock = (sock_t*)node;
+	switch (request) {
+		case FIONBIO: {
+			if (!mmu_validate_user_pointer(argp, sizeof(int), 0)) return -EFAULT;
+			sock->nonblocking = (!!*(int*)argp);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
 sock_t * net_sock_create(void) {
 	sock_t * sock = calloc(sizeof(struct SockData),1);
 	sock->_fnode.flags = FS_SOCKET; /* uh, FS_SOCKET? */
@@ -113,6 +125,7 @@ sock_t * net_sock_create(void) {
 	sock->_fnode.selectcheck = sock_generic_check;
 	sock->_fnode.selectwait = sock_generic_wait;
 	sock->_fnode.close = sock_generic_close;
+	sock->_fnode.ioctl = sock_generic_ioctl;
 	sock->alert_wait = list_create("socket alert wait", sock);
 	sock->rx_wait    = list_create("socket rx wait", sock);
 	sock->rx_queue   = list_create("socket rx queue", sock);