common/socket_close: remove now only connectd talks to peer.

connectd does this internally now using ccan/io, with appropriate
credit for ZmnSCPxj who wrote this code in the first place.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

closingd/Makefile

@@ -50,7 +50,6 @@ CLOSINGD_COMMON_OBJS :=				\
 	common/status_wiregen.o			\
 	common/read_peer_msg.o			\
 	common/setup.o				\
-	common/socket_close.o			\
 	common/status.o				\
 	common/status_wire.o			\
 	common/subdaemon.o			\

closingd/closingd.c

@@ -14,7 +14,6 @@
 #include <common/peer_io.h>
 #include <common/per_peer_state.h>
 #include <common/read_peer_msg.h>
-#include <common/socket_close.h>
 #include <common/status.h>
 #include <common/subdaemon.h>
 #include <common/type_to_string.h>
@@ -1097,10 +1096,7 @@ exit_thru_the_giftshop:
 #endif
 
 	/* We're done! */
-	/* Properly close the channel first. */
+
-	if (!socket_close(pps->peer_fd))
-		status_unusual("Closing and draining peerfd gave error: %s",
-			       strerror(errno));
 	/* Sending the below will kill us! */
 	wire_sync_write(REQ_FD, take(towire_closingd_complete(NULL)));
 	tal_free(ctx);

common/Makefile

@@ -76,7 +76,6 @@ COMMON_SRC_NOGEN :=				\
 	common/route.c				\
 	common/setup.c				\
 	common/shutdown_scriptpubkey.c		\
-	common/socket_close.c			\
 	common/sphinx.c				\
 	common/status.c				\
 	common/status_levels.c			\

common/socket_close.c

@@ -1,48 +0,0 @@
-#include "config.h"
-#include <ccan/noerr/noerr.h>
-#include <common/socket_close.h>
-#include <errno.h>
-#include <signal.h>
-#include <string.h>
-#include <sys/socket.h>
-#include <unistd.h>
-
-/* makes read() return EINTR after 5 seconds */
-static void break_read(int signum)
-{
-}
-
-bool socket_close(int fd)
-{
-	char unused[64];
-	struct sigaction act, old_act;
-	int sys_res, saved_errno;
-
-	/* We shutdown.  Usually they then shutdown too, and read() gives 0 */
-	sys_res = shutdown(fd, SHUT_WR);
-	if (sys_res < 0) {
-		close_noerr(fd);
-		return false;
-	}
-
-	/* Let's not get too enthusiastic about waiting. */
-	memset(&act, 0, sizeof(act));
-	act.sa_handler = break_read;
-	sigaction(SIGALRM, &act, &old_act);
-
-	alarm(5);
-
-	while ((sys_res = read(fd, unused, sizeof(unused))) > 0);
-	saved_errno = errno;
-
-	alarm(0);
-	sigaction(SIGALRM, &old_act, NULL);
-
-	if (sys_res < 0) {
-		close(fd);
-		errno = saved_errno;
-		return false;
-	}
-
-	return close(fd) == 0;
-}

common/socket_close.h

@@ -1,23 +0,0 @@
-/* common/socket_close - Properly close a socket,
- * ensuring that any data we write just before
- * the close has been transmitted to the other
- * side, and ignoring any data the other side
- * has sent at the time the close was started.
- *
- * Reference:
- *
- * http://ia800504.us.archive.org/3/items/TheUltimateSo_lingerPageOrWhyIsMyTcpNotReliable/the-ultimate-so_linger-page-or-why-is-my-tcp-not-reliable.html
- */
-#ifndef LIGHTNING_COMMON_SOCKET_CLOSE_H
-#define LIGHTNING_COMMON_SOCKET_CLOSE_H
-#include "config.h"
-#include <stdbool.h>
-
-/* Return false if something failed, true if
- * nothing failed.
- * If something failed, error is stored in
- * `errno.
- */
-bool socket_close(int fd);
-
-#endif /* LIGHTNING_COMMON_SOCKET_CLOSE_H */