wip host net timeout

8 files changed, 173 insertions, 25 deletions

diff --git a/libhw/CMakeLists.txt b/libhw/CMakeLists.txt
index 521e697..47ffbdd 100644
--- a/libhw/CMakeLists.txt
+++ b/libhw/CMakeLists.txt
@@ -12,11 +12,13 @@ target_link_libraries(libhw INTERFACE
 if (PICO_PLATFORM STREQUAL "rp2040")
 	target_include_directories(libhw SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/rp2040_include)
 	target_sources(libhw INTERFACE
+		rp2040_bootclock.c
 		rp2040_hwspi.c
 		w5500.c
 	)
 	target_link_libraries(libhw INTERFACE
 		pico_time
+		hardware_timer
 		hardware_gpio
 		hardware_spi
 	)
@@ -25,6 +27,7 @@ endif()
 if (PICO_PLATFORM STREQUAL "host")
 	target_include_directories(libhw SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/host_include)
 	target_sources(libhw INTERFACE
+		host_bootclock.c
 		host_net.c
 	)
 endif()
diff --git a/libhw/common_include/libhw/generic/bootclock.h b/libhw/common_include/libhw/generic/bootclock.h
new file mode 100644
index 0000000..bea5338
--- /dev/null
+++ b/libhw/common_include/libhw/generic/bootclock.h
@@ -0,0 +1,22 @@
+/* libhw/generic/bootclock.h - Device-independent clock definitions
+ *
+ * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#ifndef _LIBHW_GENERIC_BOOTCLOCK_H_
+#define _LIBHW_GENERIC_BOOTCLOCK_H_
+
+#include <stdint.h> /* for uint{n}_t and UINT{n}_C */
+
+#define NS_PER_S UINT64_C(1000000000) /* needs at least log₂(10⁹) ≈ 29.9 bits */
+#define US_PER_S UINT64_C(1000000)    /* needs at least log₂(10⁶) ≈ 19.9 bits */
+#define MS_PER_S UINT64_C(1000)       /* needs at least log₂(10³) ≈  9.9 bits */
+
+/**
+ * (2⁶⁴-1 nanoseconds is more than 500 years; there is little
+ * risk of this overflowing)
+ */
+uint64_t bootclock_get_ns(void);
+
+#endif /* _LIBHW_GENERIC_BOOTCLOCK_H_ */
diff --git a/libhw/common_include/libhw/generic/net.h b/libhw/common_include/libhw/generic/net.h
index 419a8f2..af8844f 100644
--- a/libhw/common_include/libhw/generic/net.h
+++ b/libhw/common_include/libhw/generic/net.h
@@ -61,6 +61,20 @@ struct net_stream_conn_vtable {
 	                                 void *buf, size_t count);
 
 	/**
+	 * Set a timestamp after which calls to read() will return
+	 * NET_ETIMEDOUT.  The timestamp is in nanoseconds on the
+	 * system monotonic clock, which is usually (on pico-sdk and
+	 * on the Linux kernel) nanoseconds-since-boot.
+	 *
+	 * A zero value disables the deadline.
+	 *
+	 * (2⁶⁴-1 nanoseconds is more than 500 years; there is little
+	 * risk of this overflowing)
+	 */
+	void                     (*set_read_deadline)(implements_net_stream_conn *self,
+	                                              uint64_t ns_since_boot);
+
+	/**
 	 * Return `count` on success, -errno on error; a short write *is* an
 	 * error.
 	 *
@@ -93,6 +107,8 @@ struct net_packet_conn_vtable {
 	ssize_t (*recvfrom)(implements_net_packet_conn *self,
 	                    void *buf, size_t len,
 	                    struct net_ip4_addr *ret_node, uint16_t *ret_port);
+	void    (*set_read_deadline)(implements_net_packet_conn *self,
+	                             uint64_t ns_since_boot);
 	int     (*close   )(implements_net_packet_conn *self);
 };
 
diff --git a/libhw/host_bootclock.c b/libhw/host_bootclock.c
new file mode 100644
index 0000000..ca9565c
--- /dev/null
+++ b/libhw/host_bootclock.c
@@ -0,0 +1,20 @@
+/* libhw/host_bootclock.c - <libhw/generic/bootclock.h> implementation for POSIX hosts
+ *
+ * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#include <assert.h>
+#include <time.h> /* for clock_gettime(), CLOCK_MONOTONIC, struct timespec */
+
+#include <libhw/generic/bootclock.h>
+
+uint64_t bootclock_get_ns(void) {
+	struct timespec ts;
+	int r;
+
+	r = clock_gettime(CLOCK_MONOTONIC, &ts);
+	assert(r == 0);
+
+	return (((uint64_t)ts.tv_sec) * NS_PER_S) + (uint64_t)ts.tv_nsec;
+}
diff --git a/libhw/host_include/libhw/host_net.h b/libhw/host_include/libhw/host_net.h
index 7a0dff4..1b1ba7a 100644
--- a/libhw/host_include/libhw/host_net.h
+++ b/libhw/host_include/libhw/host_net.h
@@ -15,13 +15,14 @@ struct _hostnet_tcp_conn {
 	implements_net_stream_conn;
 
 	int                              fd;
+	uint64_t                         read_deadline_ns;
 };
 
 struct hostnet_tcp_listener {
 	implements_net_stream_listener;
 
 	int                              fd;
-	struct _hostnet_tcp_conn            active_conn;
+	struct _hostnet_tcp_conn         active_conn;
 };
 
 void hostnet_tcp_listener_init(struct hostnet_tcp_listener *self, uint16_t port);
@@ -30,6 +31,7 @@ struct hostnet_udp_conn {
 	implements_net_packet_conn;
 
 	int                              fd;
+	uint64_t                         read_deadline_ns;
 };
 
 void hostnet_udp_conn_init(struct hostnet_udp_conn *self, uint16_t port);
diff --git a/libhw/host_net.c b/libhw/host_net.c
index fcdac57..1563ced 100644
--- a/libhw/host_net.c
+++ b/libhw/host_net.c
@@ -22,6 +22,7 @@
 #include <libcr/coroutine.h>
 #include <libmisc/vcall.h>
 
+#include <libhw/generic/bootclock.h>
 #include <libhw/host_net.h>
 
 /* common *********************************************************************/
@@ -86,18 +87,20 @@ static inline ssize_t hostnet_map_errno(ssize_t v) {
 /* TCP init() ( AKA socket(3) + listen(3) )************************************/
 
 static implements_net_stream_conn *hostnet_tcp_accept(implements_net_stream_listener *_listener);
+static void    hostnet_tcp_set_read_deadline(implements_net_stream_conn *conn, uint64_t ts_ns);
 static ssize_t hostnet_tcp_read(implements_net_stream_conn *conn, void *buf, size_t count);
 static ssize_t hostnet_tcp_write(implements_net_stream_conn *conn, void *buf, size_t count);
-static int hostnet_tcp_close(implements_net_stream_conn *conn, bool rd, bool wr);
+static int     hostnet_tcp_close(implements_net_stream_conn *conn, bool rd, bool wr);
 
 static struct net_stream_listener_vtable hostnet_tcp_listener_vtable = {
 	.accept = hostnet_tcp_accept,
 };
 
 static struct net_stream_conn_vtable hostnet_tcp_conn_vtable = {
-	.read  = hostnet_tcp_read,
-	.write = hostnet_tcp_write,
-	.close = hostnet_tcp_close,
+	.set_read_deadline = hostnet_tcp_set_read_deadline,
+	.read              = hostnet_tcp_read,
+	.write             = hostnet_tcp_write,
+	.close             = hostnet_tcp_close,
 };
 
 void hostnet_tcp_listener_init(struct hostnet_tcp_listener *self, uint16_t port) {
@@ -145,7 +148,7 @@ static void *hostnet_pthread_accept(void *_args) {
 		*(args->ret_connfd) = -errno;
 	WAKE_COROUTINE(args);
 	return NULL;
-};
+}
 
 static implements_net_stream_conn *hostnet_tcp_accept(implements_net_stream_listener *_listener) {
 	struct hostnet_tcp_listener *listener =
@@ -169,11 +172,20 @@ static implements_net_stream_conn *hostnet_tcp_accept(implements_net_stream_list
 
 /* TCP read() *****************************************************************/
 
+static void hostnet_tcp_set_read_deadline(implements_net_stream_conn *_conn, uint64_t ts_ns) {
+	struct _hostnet_tcp_conn *conn =
+		VCALL_SELF(struct _hostnet_tcp_conn, implements_net_stream_conn, _conn);
+	assert(conn);
+
+	conn->read_deadline_ns = ts_ns;
+}
+
 struct hostnet_pthread_read_args {
 	pthread_t        cr_thread;
 	cid_t            cr_coroutine;
 
 	int              connfd;
+	struct timeval   timeout;
 	void            *buf;
 	size_t           count;
 
@@ -182,12 +194,22 @@ struct hostnet_pthread_read_args {
 
 static void *hostnet_pthread_read(void *_args) {
 	struct hostnet_pthread_read_args *args = _args;
+
+	*(args->ret) = setsockopt(args->connfd, SOL_SOCKET, SO_RCVTIMEO,
+	                          &args->timeout, sizeof(args->timeout));
+	if (*(args->ret) < 0)
+		goto end;
+
 	*(args->ret) = read(args->connfd, args->buf, args->count);
 	if (*(args->ret) < 0)
+		goto end;
+
+ end:
+	if (*(args->ret) < 0)
 		*(args->ret) = hostnet_map_errno(-errno);
 	WAKE_COROUTINE(args);
 	return NULL;
-};
+}
 
 static ssize_t hostnet_tcp_read(implements_net_stream_conn *_conn, void *buf, size_t count) {
 	struct _hostnet_tcp_conn *conn =
@@ -205,6 +227,20 @@ static ssize_t hostnet_tcp_read(implements_net_stream_conn *_conn, void *buf, si
 
 		.ret          = &ret,
 	};
+	if (conn->read_deadline_ns) {
+		uint64_t now_ns = bootclock_get_ns();
+		if (conn->read_deadline_ns < now_ns)
+			return -NET_ETIMEDOUT;
+		uint64_t timeout_ns = conn->read_deadline_ns-now_ns;
+		args.timeout.tv_sec = timeout_ns
+			/NS_PER_S;
+		args.timeout.tv_usec = (timeout_ns - ((uint64_t)args.timeout.tv_sec)*NS_PER_S)
+			/(NS_PER_S/US_PER_S);
+	} else {
+		args.timeout.tv_sec = 0;
+		args.timeout.tv_usec = 0;
+	}
+
 	if (RUN_PTHREAD(hostnet_pthread_read, &args))
 		return -NET_ETHREAD;
 	return ret;
@@ -238,7 +274,7 @@ static void *hostnet_pthread_write(void *_args) {
 		*(args->ret) = done;
 	WAKE_COROUTINE(args);
 	return NULL;
-};
+}
 
 static ssize_t hostnet_tcp_write(implements_net_stream_conn *_conn, void *buf, size_t count) {
 	struct _hostnet_tcp_conn *conn =
@@ -282,6 +318,8 @@ static int hostnet_tcp_close(implements_net_stream_conn *_conn, bool rd, bool wr
 
 /* UDP init() *****************************************************************/
 
+static void    hostnet_udp_set_read_deadline(implements_net_packet_conn *self,
+                                             uint64_t ts_ns);
 static ssize_t hostnet_udp_sendto(implements_net_packet_conn *self, void *buf, size_t len,
                                   struct net_ip4_addr addr, uint16_t port);
 static ssize_t hostnet_udp_recvfrom(implements_net_packet_conn *self, void *buf, size_t len,
@@ -289,9 +327,10 @@ static ssize_t hostnet_udp_recvfrom(implements_net_packet_conn *self, void *buf,
 static int     hostnet_udp_close(implements_net_packet_conn *self);
 
 static struct net_packet_conn_vtable hostnet_udp_conn_vtable = {
-	.sendto   = hostnet_udp_sendto,
-	.recvfrom = hostnet_udp_recvfrom,
-	.close    = hostnet_udp_close,
+	.set_read_deadline = hostnet_udp_set_read_deadline,
+	.sendto            = hostnet_udp_sendto,
+	.recvfrom          = hostnet_udp_recvfrom,
+	.close             = hostnet_udp_close,
 };
 
 void hostnet_udp_conn_init(struct hostnet_udp_conn *self, uint16_t port) {
@@ -354,7 +393,7 @@ static void *hostnet_pthread_sendto(void *_args) {
 }
 
 static ssize_t hostnet_udp_sendto(implements_net_packet_conn *_conn, void *buf, size_t count,
-                               struct net_ip4_addr node, uint16_t port) {
+                                  struct net_ip4_addr node, uint16_t port) {
 	struct hostnet_udp_conn *conn =
 		VCALL_SELF(struct hostnet_udp_conn, implements_net_packet_conn, _conn);
 	assert(conn);
@@ -379,11 +418,21 @@ static ssize_t hostnet_udp_sendto(implements_net_packet_conn *_conn, void *buf,
 
 /* UDP recvfrom() *************************************************************/
 
+static void hostnet_udp_set_read_deadline(implements_net_packet_conn *_conn,
+                                          uint64_t ts_ns) {
+	struct hostnet_udp_conn *conn =
+		VCALL_SELF(struct hostnet_udp_conn, implements_net_packet_conn, _conn);
+	assert(conn);
+
+	conn->read_deadline_ns = ts_ns;
+}
+
 struct hostnet_pthread_recvfrom_args {
 	pthread_t                cr_thread;
 	cid_t                    cr_coroutine;
 
 	int                      connfd;
+	struct timeval           timeout;
 	void                    *buf;
 	size_t                   count;
 
@@ -402,26 +451,35 @@ static void *hostnet_pthread_recvfrom(void *_args) {
 	} addr = { 0 };
 	socklen_t addr_size;
 
+	*(args->ret_size) = setsockopt(args->connfd, SOL_SOCKET, SO_RCVTIMEO,
+	                               &args->timeout, sizeof(args->timeout));
+	if (*(args->ret_size) < 0)
+		goto end;
+
 	*(args->ret_size) = recvfrom(args->connfd, args->buf, args->count, 0, &addr.gen, &addr_size);
 	if (*(args->ret_size) < 0)
-		*(args->ret_size) = hostnet_map_errno(-errno);
-	else {
-		assert(addr.in.sin_family == AF_INET);
-		if (args->ret_node) {
-			args->ret_node->octets[0] = (addr.in.sin_addr.s_addr >> 24) & 0xFF;
-			args->ret_node->octets[1] = (addr.in.sin_addr.s_addr >> 16) & 0xFF;
-			args->ret_node->octets[2] = (addr.in.sin_addr.s_addr >>  8) & 0xFF;
-			args->ret_node->octets[3] = (addr.in.sin_addr.s_addr >>  0) & 0xFF;
-		}
-		if (args->ret_port)
-			(*args->ret_port) = ntohs(addr.in.sin_port);
+		goto end;
+
+	assert(addr.in.sin_family == AF_INET);
+	if (args->ret_node) {
+		args->ret_node->octets[0] = (addr.in.sin_addr.s_addr >> 24) & 0xFF;
+		args->ret_node->octets[1] = (addr.in.sin_addr.s_addr >> 16) & 0xFF;
+		args->ret_node->octets[2] = (addr.in.sin_addr.s_addr >>  8) & 0xFF;
+		args->ret_node->octets[3] = (addr.in.sin_addr.s_addr >>  0) & 0xFF;
 	}
+	if (args->ret_port) {
+		(*args->ret_port) = ntohs(addr.in.sin_port);
+	}
+
+ end:
+	if (*(args->ret_size) < 0)
+		*(args->ret_size) = hostnet_map_errno(-errno);
 	WAKE_COROUTINE(args);
 	return NULL;
 }
 
 static ssize_t hostnet_udp_recvfrom(implements_net_packet_conn *_conn, void *buf, size_t count,
-                                 struct net_ip4_addr *ret_node, uint16_t *ret_port) {
+                                    struct net_ip4_addr *ret_node, uint16_t *ret_port) {
 	struct hostnet_udp_conn *conn =
 		VCALL_SELF(struct hostnet_udp_conn, implements_net_packet_conn, _conn);
 	assert(conn);
@@ -439,6 +497,20 @@ static ssize_t hostnet_udp_recvfrom(implements_net_packet_conn *_conn, void *buf
 		.ret_node     = ret_node,
 		.ret_port     = ret_port,
 	};
+	if (conn->read_deadline_ns) {
+		uint64_t now_ns = bootclock_get_ns();
+		if (conn->read_deadline_ns < now_ns)
+			return -NET_ETIMEDOUT;
+		uint64_t timeout_ns = conn->read_deadline_ns-now_ns;
+		args.timeout.tv_sec = timeout_ns
+			/NS_PER_S;
+		args.timeout.tv_usec = (timeout_ns - ((uint64_t)args.timeout.tv_sec)*NS_PER_S)
+			/(NS_PER_S/US_PER_S);
+	} else {
+		args.timeout.tv_sec = 0;
+		args.timeout.tv_usec = 0;
+	}
+
 	if (RUN_PTHREAD(hostnet_pthread_recvfrom, &args))
 		return -NET_ETHREAD;
 	return ret;
diff --git a/libhw/rp2040_bootclock.c b/libhw/rp2040_bootclock.c
new file mode 100644
index 0000000..0484910
--- /dev/null
+++ b/libhw/rp2040_bootclock.c
@@ -0,0 +1,13 @@
+/* libhw/rp2040_bootclock.c - <libhw/generic/bootclock.h> implementation for pico-sdk
+ *
+ * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#include <hardware/timer.h> /* pico-sdk:hardware_timer */
+
+#include <libhw/generic/bootclock.h>
+
+uint64_t bootclock_get_ns(void) {
+	return time_us_64()*(NS_PER_S/US_PER_S);
+}
diff --git a/notes.md b/notes.md
index 255b765..5ecb152 100644
--- a/notes.md
+++ b/notes.md
@@ -15,7 +15,7 @@ Which file to include:
 | `U{CHAR,SHRT,INT,LONG,LLONG}_MAX`        | `<limits.h>`                      |                                |
 |------------------------------------------|-----------------------------------|--------------------------------|
 | C SIZED INTS                             |                                   |                                |
-| `(C u)int{n}_t` (and `_{MIN,MAX,C}`)     | `<stdint.h>`                      | exact                          |
+| `(u)int{n}_t` (and `_{MIN,MAX,C}`)       | `<stdint.h>`                      | exact                          |
 | `(u)int_least{n}_t` (and `_{MIN,MAX,C}`) | `<stdint.h>`                      | type may be more than `n` bits |
 | `(u)int_fast{n}_t` (and `_{MIN,MAX,C}`)  | `<stdint.h>`                      | type may be more than `n` bits |
 | `(u)intptr_t` (and `_{MIN,MAX,C}`)       | `<stdint.h>`                      |                                |