more select-tests updates

[Bruno Haible]

Hi Paolo,

While looking at tests/test-select.c for the OSF/1 failure, I found a couple
of small tweaks. Can you agree to these 4 patches?


1) The code for pipe() on Win32 is now in module 'pipe-posix'. And 'pipe-posix'
depends on 'unistd'.

2010-12-24  Bruno Haible  <address@hidden>

        select tests: Use existing modules.
        * modules/select-tests (Depends-on): Add pipe-posix, unistd.
        (configure.ac): Don't test for unistd.h.
        * tests/test-select.c: Include <unistd.h> always. Use pipe() as
        declared in <unistd.h>.

--- modules/select-tests.orig   Sat Dec 25 01:33:20 2010
+++ modules/select-tests        Sat Dec 25 01:33:15 2010
@@ -11,11 +11,13 @@
 stdbool
 netinet_in
 arpa_inet
+unistd
 sys_ioctl
 extensions
 inet_pton
 errno
 perror
+pipe-posix
 socket
 bind
 setsockopt
@@ -27,7 +29,7 @@
 gettimeofday
 
 configure.ac:
-AC_CHECK_HEADERS_ONCE([unistd.h sys/wait.h])
+AC_CHECK_HEADERS_ONCE([sys/wait.h])
 
 Makefile.am:
 TESTS += test-select test-select-in.sh test-select-out.sh
--- tests/test-select.c.orig    Sat Dec 25 01:33:20 2010
+++ tests/test-select.c Sat Dec 25 01:32:02 2010
@@ -42,6 +42,7 @@
 #include <string.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <unistd.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <stdbool.h>
@@ -56,25 +57,18 @@
 # define WIN32_NATIVE
 #endif
 
-#ifdef WIN32_NATIVE
-#include <io.h>
-#define pipe(x) _pipe(x, 256, O_BINARY)
-#endif
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
 #ifdef HAVE_SYS_WAIT_H
-#include <sys/wait.h>
+# include <sys/wait.h>
 #endif
 
 #ifndef SO_REUSEPORT
-#define SO_REUSEPORT    SO_REUSEADDR
+# define SO_REUSEPORT    SO_REUSEADDR
 #endif
 
 #define TEST_PORT       12345


2) The arguments passed to function connect_to_socket() are true and false.
So it's actually a 'bool' argument.

2010-12-24  Bruno Haible  <address@hidden>

        select tests: Use 'bool' where appropriate.
        * tests/test-select.c (connect_to_socket): Change argument type to
        'bool'.

--- tests/test-select.c.orig    Sat Dec 25 01:33:20 2010
+++ tests/test-select.c Sat Dec 25 01:32:02 2010
@@ -134,7 +126,7 @@
 }
 
 static int
-connect_to_socket (int blocking)
+connect_to_socket (bool blocking)
 {
   int s;
   struct sockaddr_in ia;


3) Because at least some Linux versions return in the timeout parameter the
unslept time (see <http://linux.die.net/man/2/select>), it is good practice
to not reuse a 'struct timeval' from a previous select() call for the next
select() call. Even though in this case the unslept time is probably
always zero, better use the safe way of coding.

2010-12-24  Bruno Haible  <address@hidden>

        select tests: Safer way of handling timeout.
        * tests/test-select.c (do_select_nowait): Zero-initialize the timeout
        at every invocation.

--- tests/test-select.c.orig    Sat Dec 25 01:33:20 2010
+++ tests/test-select.c Sat Dec 25 01:32:02 2010
@@ -210,7 +212,9 @@
 static int
 do_select_nowait (int fd, int ev)
 {
-  static struct timeval tv0;
+  struct timeval tv0;
+  tv0.tv_sec = 0;
+  tv0.tv_usec = 0;
   return do_select (fd, ev, &tv0);
 }
 


4) A couple of comments for do_select(), since this function is used in all
the tests. (The reader may not be familiar with poll().)

2010-12-24  Bruno Haible  <address@hidden>

        select tests: Improve comments.
        * tests/test-select.c (do_select): Add comments.

--- tests/test-select.c.orig    Sat Dec 25 01:33:20 2010
+++ tests/test-select.c Sat Dec 25 01:32:02 2010
@@ -50,8 +51,6 @@
 
 #include "macros.h"
 
-enum { SEL_IN = 1, SEL_OUT = 2, SEL_EXC = 4 };
-
 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 # define WIN32_NATIVE
 #endif
@@ -171,10 +163,20 @@
 }
 
 
-/* A slightly more convenient interface to select(2).  */
+/* A slightly more convenient interface to select(2).
+   Waits until a specific event occurs on a file descriptor FD.
+   EV is a bit mask of events to look for:
+     SEL_IN - input can be polled without blocking,
+     SEL_OUT - output can be provided without blocking,
+     SEL_EXC - an exception occurred,
+   A maximum wait time is specified by TIMEOUT.
+   *TIMEOUT = { 0, 0 } means to return immediately,
+   TIMEOUT = NULL means to wait indefinitely.  */
+
+enum { SEL_IN = 1, SEL_OUT = 2, SEL_EXC = 4 };
 
 static int
-do_select (int fd, int ev, struct timeval *tv)
+do_select (int fd, int ev, struct timeval *timeout)
 {
   fd_set rfds, wfds, xfds;
   int r, rev;
@@ -188,7 +190,7 @@
     FD_SET (fd, &wfds);
   if (ev & SEL_EXC)
     FD_SET (fd, &xfds);
-  r = select (fd + 1, &rfds, &wfds, &xfds, tv);
+  r = select (fd + 1, &rfds, &wfds, &xfds, timeout);
   if (r < 0)
     return r;
 
@@ -221,7 +225,7 @@
 }
 
 
-/* Test poll(2) for TTYs.  */
+/* Test select(2) for TTYs.  */
 
 #ifdef INTERACTIVE
 static void
@@ -242,7 +246,7 @@
 #endif
 
 
-/* Test poll(2) for unconnected nonblocking sockets.  */
+/* Test select(2) for unconnected nonblocking sockets.  */
 
 static void
 test_connect_first (void)
@@ -271,7 +275,7 @@
 }
 
 
-/* Test poll(2) for unconnected blocking sockets.  */
+/* Test select(2) for unconnected blocking sockets.  */
 
 static void
 test_accept_first (void)
@@ -337,7 +341,7 @@
 }
 
 
-/* Test poll(2) on connected sockets.  */
+/* Test select(2) on connected sockets.  */
 
 static void
 test_socket_pair (void)
@@ -358,7 +362,7 @@
 }
 
 
-/* Test poll(2) on pipes.  */
+/* Test select(2) on pipes.  */
 
 static void
 test_pipe (void)