on Unix-ish platforms, apr_wait_for_io_or_timeout() can just use poll(2)

it is a perfect match for the feature set needed and avoids the setup
code at object creation time currently required to use apr_pollset_poll()
instead of poll(2)

future:
  select()-based function is trivial too

  is any platform then left needing the support in
  apr/(network_io|file_io)/unix for allocating a pollset any time we
  create a file or socket just in case apr_wait_for_io_or_timeout()
  will be called?


git-svn-id: http://svn.apache.org/repos/asf/apr/apr/trunk@64794 13f79535-47bb-0310-9956-ffa450edef68

8 files changed, 63 insertions, 13 deletions

diff --git a/configure.in b/configure.in
index 164c8c502..84f04c5e3 100644
--- a/configure.in
+++ b/configure.in
@@ -1720,6 +1720,11 @@ fi
 AC_SUBST(have_in_addr)
 AC_SUBST(file_as_socket)
 
+if test "$ac_cv_func_poll $file_as_socket" = "yes 1"; then
+    AC_DEFINE(WAITIO_USES_POLL, 1,
+              [Define if apr_wait_for_io_or_timeout() uses poll(2)])
+fi
+
 # Check the types only if we have gethostbyname_r
 if test "$ac_cv_func_gethostbyname_r" = "yes"; then
     APR_CHECK_GETHOSTBYNAME_R_STYLE
diff --git a/file_io/unix/filedup.c b/file_io/unix/filedup.c
index 04aa9a105..f89e2e5a5 100644
--- a/file_io/unix/filedup.c
+++ b/file_io/unix/filedup.c
@@ -130,11 +130,11 @@ static apr_status_t file_dup(apr_file_t **new_file,
     apr_pool_cleanup_register((*new_file)->pool, (void *)(*new_file),
                               apr_unix_file_cleanup, 
                               apr_unix_file_cleanup);
-
+#ifndef WAITIO_USES_POLL
     /* Create a pollset with room for one descriptor. */
     /* ### check return codes */
     (void) apr_pollset_create(&(*new_file)->pollset, 1, p, 0);
-
+#endif
     return APR_SUCCESS;
 }
 
@@ -187,10 +187,10 @@ APR_DECLARE(apr_status_t) apr_file_setaside(apr_file_t **new_file,
     old_file->filedes = -1;
     apr_pool_cleanup_kill(old_file->pool, (void *)old_file,
                           apr_unix_file_cleanup);
-
+#ifndef WAITIO_USES_POLL
     /* Create a pollset with room for one descriptor. */
     /* ### check return codes */
     (void) apr_pollset_create(&(*new_file)->pollset, 1, p, 0);
-
+#endif
     return APR_SUCCESS;
 }
diff --git a/file_io/unix/open.c b/file_io/unix/open.c
index df67b765b..54775e3c8 100644
--- a/file_io/unix/open.c
+++ b/file_io/unix/open.c
@@ -188,11 +188,11 @@ APR_DECLARE(apr_status_t) apr_file_open(apr_file_t **new,
     (*new)->bufpos = 0;
     (*new)->dataRead = 0;
     (*new)->direction = 0;
-
+#ifndef WAITIO_USES_POLL
     /* Create a pollset with room for one descriptor. */
     /* ### check return codes */
     (void) apr_pollset_create(&(*new)->pollset, 1, pool, 0);
-
+#endif
     if (!(flag & APR_FILE_NOCLEANUP)) {
         apr_pool_cleanup_register((*new)->pool, (void *)(*new), 
                                   apr_unix_file_cleanup, 
diff --git a/file_io/unix/pipe.c b/file_io/unix/pipe.c
index 140c98f8e..5ab52cbdd 100644
--- a/file_io/unix/pipe.c
+++ b/file_io/unix/pipe.c
@@ -198,10 +198,11 @@ APR_DECLARE(apr_status_t) apr_os_pipe_put_ex(apr_file_t **file,
                                   apr_unix_file_cleanup,
                                   apr_pool_cleanup_null);
     }
-
+#ifndef WAITIO_USES_POLL
     /* Create a pollset with room for one descriptor. */
     /* ### check return codes */
     (void) apr_pollset_create(&(*file)->pollset, 1, pool, 0);
+#endif
     return APR_SUCCESS;
 }
 
@@ -233,8 +234,9 @@ APR_DECLARE(apr_status_t) apr_file_pipe_create(apr_file_t **in, apr_file_t **out
 #if APR_HAS_THREADS
     (*in)->thlock = NULL;
 #endif
+#ifndef WAITIO_USES_POLL
     (void) apr_pollset_create(&(*in)->pollset, 1, pool, 0);
-
+#endif
     (*out) = (apr_file_t *)apr_pcalloc(pool, sizeof(apr_file_t));
     (*out)->pool = pool;
     (*out)->filedes = filedes[1];
@@ -247,8 +249,9 @@ APR_DECLARE(apr_status_t) apr_file_pipe_create(apr_file_t **in, apr_file_t **out
 #if APR_HAS_THREADS
     (*out)->thlock = NULL;
 #endif
+#ifndef WAITIO_USES_POLL
     (void) apr_pollset_create(&(*out)->pollset, 1, pool, 0);
-
+#endif
     apr_pool_cleanup_register((*in)->pool, (void *)(*in), apr_unix_file_cleanup,
                          apr_pool_cleanup_null);
     apr_pool_cleanup_register((*out)->pool, (void *)(*out), apr_unix_file_cleanup,
diff --git a/include/arch/unix/apr_arch_file_io.h b/include/arch/unix/apr_arch_file_io.h
index aea12e791..3ee5ab8b0 100644
--- a/include/arch/unix/apr_arch_file_io.h
+++ b/include/arch/unix/apr_arch_file_io.h
@@ -64,7 +64,9 @@
 #include "apr_errno.h"
 #include "apr_lib.h"
 #include "apr_thread_mutex.h"
+#ifndef WAITIO_USES_POLL
 #include "apr_poll.h"
+#endif
 
 /* System headers the file I/O library needs */
 #if APR_HAVE_FCNTL_H
@@ -131,10 +133,10 @@ struct apr_file_t {
     int buffered;
     enum {BLK_UNKNOWN, BLK_OFF, BLK_ON } blocking;
     int ungetchar;    /* Last char provided by an unget op. (-1 = no char)*/
-
+#ifndef WAITIO_USES_POLL
     /* if there is a timeout set, then this pollset is used */
     apr_pollset_t *pollset;
-
+#endif
     /* Stuff for buffered mode */
     char *buffer;
     int bufpos;               /* Read/Write position in buffer */
diff --git a/include/arch/unix/apr_arch_networkio.h b/include/arch/unix/apr_arch_networkio.h
index 4938cf6bc..ef5027354 100644
--- a/include/arch/unix/apr_arch_networkio.h
+++ b/include/arch/unix/apr_arch_networkio.h
@@ -61,7 +61,9 @@
 #include "apr_errno.h"
 #include "apr_general.h"
 #include "apr_lib.h"
+#ifndef WAITIO_USES_POLL
 #include "apr_poll.h"
+#endif
 
 /* System headers the network I/O library needs */
 #if APR_HAVE_SYS_TYPES_H
@@ -153,9 +155,10 @@ struct apr_socket_t {
     apr_int32_t options;
     apr_int32_t inherit;
     sock_userdata_t *userdata;
-
+#ifndef WAITIO_USES_POLL
     /* if there is a timeout set, then this pollset is used */
     apr_pollset_t *pollset;
+#endif
 };
 
 const char *apr_inet_ntop(int af, const void *src, char *dst, apr_size_t size);
diff --git a/network_io/unix/sockets.c b/network_io/unix/sockets.c
index 342f619cc..1c1638932 100644
--- a/network_io/unix/sockets.c
+++ b/network_io/unix/sockets.c
@@ -103,10 +103,11 @@ static void alloc_socket(apr_socket_t **new, apr_pool_t *p)
     (*new)->remote_addr = (apr_sockaddr_t *)apr_pcalloc((*new)->cntxt,
                                                         sizeof(apr_sockaddr_t));
     (*new)->remote_addr->pool = p;
-
+#ifndef WAITIO_USES_POLL
     /* Create a pollset with room for one descriptor. */
     /* ### check return codes */
     (void) apr_pollset_create(&(*new)->pollset, 1, p, 0);
+#endif
 }
 
 apr_status_t apr_socket_protocol_get(apr_socket_t *sock, int *protocol)
diff --git a/support/unix/waitio.c b/support/unix/waitio.c
index 84a8483c7..be918b13d 100644
--- a/support/unix/waitio.c
+++ b/support/unix/waitio.c
@@ -66,6 +66,41 @@
 
 #ifdef USE_WAIT_FOR_IO
 
+#ifdef WAITIO_USES_POLL
+
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
+#ifdef HAVE_SYS_POLL_H
+#include <sys/poll.h>
+#endif
+
+apr_status_t apr_wait_for_io_or_timeout(apr_file_t *f, apr_socket_t *s,
+                                        int for_read)
+{
+    struct pollfd pfd;
+    int rc, timeout;
+
+    timeout    = f        ? f->timeout / 1000 : s->timeout / 1000;
+    pfd.fd     = f        ? f->filedes        : s->socketdes;
+    pfd.events = for_read ? POLLIN            : POLLOUT;
+
+    do {
+        rc = poll(&pfd, 1, timeout);
+    } while (rc == -1 && errno == EINTR);
+    if (rc == 0) {
+        return APR_TIMEUP;
+    }
+    else if (rc > 0) {
+        return APR_SUCCESS;
+    }
+    else {
+        return errno;
+    }
+}
+
+#else
+
 apr_status_t apr_wait_for_io_or_timeout(apr_file_t *f, apr_socket_t *s,
                                         int for_read)
 {
@@ -114,5 +149,6 @@ apr_status_t apr_wait_for_io_or_timeout(apr_file_t *f, apr_socket_t *s,
 
     return status;
 }
+#endif /* WAITIO_USES_POLL */
 
 #endif /* USE_WAIT_FOR_IO */