socket: memoize common socket families in fptr->mode

This provides a minor speedup by avoiding an extra syscall

	require 'socket'
	require 'benchmark'
	nr = 100000
	msg = 'hello world'
	buf = ''
	size = msg.bytesize
	puts(Benchmark.measure do
	  UNIXSocket.pair(:SEQPACKET) do |a, b|
	    nr.times do
	      a.sendmsg_nonblock(msg, 0, exception: false)
	      b.recv(size, 0, buf)
	    end
	  end
	end)

             user     system      total        real
before:  0.330000   0.340000   0.670000 (  0.678235)
 after:  0.290000   0.240000   0.530000 (  0.534527)

* ext/socket/rubysocket.h: flags for common socket families
  (rsock_getfamily): update signature
* include/ruby/io.h: comment socket FMODE flags
* ext/socket/init.c (rsock_getfamily): memoize family
* ext/socket/basicsocket.c: adjust rsock_getfamily calls
* ext/socket/ancdata.c: ditto
  [ruby-core:69713] [Feature #11298]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51097 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 32 insertions, 7 deletions

diff --git a/ext/socket/ancdata.c b/ext/socket/ancdata.c
index d0290ba07a..da8b8160d2 100644
--- a/ext/socket/ancdata.c
+++ b/ext/socket/ancdata.c
@@ -1146,7 +1146,7 @@ bsock_sendmsg_internal(int argc, VALUE *argv, VALUE sock, int nonblock)
 
     GetOpenFile(sock, fptr);
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
-    family = rsock_getfamily(fptr->fd);
+    family = rsock_getfamily(fptr);
 #endif
 
     data = vflags = dest_sockaddr = Qnil;
@@ -1692,7 +1692,7 @@ bsock_recvmsg_internal(int argc, VALUE *argv, VALUE sock, int nonblock)
 			 );
 
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
-    family = rsock_getfamily(fptr->fd);
+    family = rsock_getfamily(fptr);
     if (mh.msg_controllen) {
 	char *msg_end = (char *)mh.msg_control + mh.msg_controllen;
         for (cmh = CMSG_FIRSTHDR(&mh); cmh != NULL; cmh = CMSG_NXTHDR(&mh, cmh)) {
diff --git a/ext/socket/basicsocket.c b/ext/socket/basicsocket.c
index 6bc1828d61..16fa12dd38 100644
--- a/ext/socket/basicsocket.c
+++ b/ext/socket/basicsocket.c
@@ -214,7 +214,7 @@ bsock_setsockopt(int argc, VALUE *argv, VALUE sock)
     }
 
     GetOpenFile(sock, fptr);
-    family = rsock_getfamily(fptr->fd);
+    family = rsock_getfamily(fptr);
     level = rsock_level_arg(family, lev);
     option = rsock_optname_arg(family, level, optname);
 
@@ -311,7 +311,7 @@ bsock_getsockopt(VALUE sock, VALUE lev, VALUE optname)
     int family;
 
     GetOpenFile(sock, fptr);
-    family = rsock_getfamily(fptr->fd);
+    family = rsock_getfamily(fptr);
     level = rsock_level_arg(family, lev);
     option = rsock_optname_arg(family, level, optname);
     len = 256;
diff --git a/ext/socket/init.c b/ext/socket/init.c
index 34f6a116f0..00e20fa308 100644
--- a/ext/socket/init.c
+++ b/ext/socket/init.c
@@ -624,15 +624,34 @@ rsock_s_accept(VALUE klass, int fd, struct sockaddr *sockaddr, socklen_t *len)
 }
 
 int
-rsock_getfamily(int sockfd)
+rsock_getfamily(rb_io_t *fptr)
 {
     union_sockaddr ss;
     socklen_t sslen = (socklen_t)sizeof(ss);
+    int cached = fptr->mode & FMODE_SOCK;
+
+    if (cached) {
+        switch (cached) {
+#ifdef AF_UNIX
+	    case FMODE_UNIX: return AF_UNIX;
+#endif
+	    case FMODE_INET: return AF_INET;
+	    case FMODE_INET6: return AF_INET6;
+	}
+    }
 
     ss.addr.sa_family = AF_UNSPEC;
-    if (getsockname(sockfd, &ss.addr, &sslen) < 0)
+    if (getsockname(fptr->fd, &ss.addr, &sslen) < 0)
         return AF_UNSPEC;
 
+    switch (ss.addr.sa_family) {
+#ifdef AF_UNIX
+      case AF_UNIX: fptr->mode |= FMODE_UNIX; break;
+#endif
+      case AF_INET: fptr->mode |= FMODE_INET; break;
+      case AF_INET6: fptr->mode |= FMODE_INET6; break;
+    }
+
     return ss.addr.sa_family;
 }
 
diff --git a/ext/socket/rubysocket.h b/ext/socket/rubysocket.h
index d03b1c5e0b..79dd78324f 100644
--- a/ext/socket/rubysocket.h
+++ b/ext/socket/rubysocket.h
@@ -232,6 +232,12 @@ extern int rsock_do_not_reverse_lookup;
 extern int rsock_cmsg_cloexec_state;
 #define FMODE_NOREVLOOKUP 0x100
 
+/* common socket families only */
+#define FMODE_UNIX        0x00200000
+#define FMODE_INET        0x00400000
+#define FMODE_INET6       0x00800000
+#define FMODE_SOCK        (FMODE_UNIX|FMODE_INET|FMODE_INET6)
+
 extern VALUE rb_cBasicSocket;
 extern VALUE rb_cIPSocket;
 extern VALUE rb_cTCPSocket;
@@ -279,7 +285,7 @@ int rsock_optname_arg(int family, int level, VALUE optname);
 int rsock_cmsg_type_arg(int family, int level, VALUE type);
 int rsock_shutdown_how_arg(VALUE how);
 
-int rsock_getfamily(int sockfd);
+int rsock_getfamily(rb_io_t *fptr);
 
 struct rb_addrinfo {
   struct addrinfo *ai;