utils: Wrap socket() and pipe() to reduce syscalls

Some platforms provide an implementation of socket() and pipe2() that allow the
caller to specify that the resulting file descriptors should be non-blocking.

Using these allows us to potentially elide 3 calls into 1 by avoiding extraneous
calls to fcntl() to set the O_NONBLOCK flag afterwards.

In passing, change ast_alertpipe_init() to use pipe2() directly instead of the
wrapper if it is available.

Change-Id: I3ebe654fb549587537161506c6c950f4ab298bb0

diff --git a/configure b/configure
index 061845f907c20321860cc84e72dfd11f8fbfab8e..a69ba62aba17956508f5cab61b9bd315736e273a 100755 (executable)
--- a/configure
+++ b/configure
@@ -1337,6 +1337,7 @@ infodir
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -1524,6 +1525,7 @@ datadir='${datarootdir}'
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1776,6 +1778,15 @@ do
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1913,7 +1924,7 @@ fi
 for ac_var in  exec_prefix prefix bindir sbindir libexecdir datarootdir \
                datadir sysconfdir sharedstatedir localstatedir includedir \
                oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-               libdir localedir mandir
+               libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -2066,6 +2077,7 @@ Fine tuning of the installation directories:
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -14868,7 +14880,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
                       && LARGE_OFF_T % 2147483647 == 1)
                      ? 1 : -1];
@@ -14914,7 +14926,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
                       && LARGE_OFF_T % 2147483647 == 1)
                      ? 1 : -1];
@@ -14938,7 +14950,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
                       && LARGE_OFF_T % 2147483647 == 1)
                      ? 1 : -1];
@@ -14983,7 +14995,7 @@ else
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
                       && LARGE_OFF_T % 2147483647 == 1)
                      ? 1 : -1];
@@ -15007,7 +15019,7 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
     We can't simply define LARGE_OFF_T to be 9223372036854775807,
     since some C++ compilers masquerading as C compilers
     incorrectly reject 9223372036854775807.  */
-#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+#define LARGE_OFF_T ((((off_t) 1 << 31) << 31) - 1 + (((off_t) 1 << 31) << 31))
   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
                       && LARGE_OFF_T % 2147483647 == 1)
                      ? 1 : -1];
@@ -16307,6 +16319,8 @@ main ()
     if (*(data + i) != *(data3 + i))
       return 14;
   close (fd);
+  free (data);
+  free (data3);
   return 0;
 }
 _ACEOF
@@ -16847,7 +16861,7 @@ fi
 done
 
 
-for ac_func in asprintf atexit closefrom dup2 eaccess endpwent euidaccess ffsll ftruncate getcwd gethostbyname gethostname getloadavg gettimeofday glob ioperm inet_ntoa isascii memchr memmove memset mkdir mkdtemp munmap newlocale ppoll putenv re_comp regcomp select setenv socket strcasecmp strcasestr strchr strcspn strdup strerror strlcat strlcpy strncasecmp strndup strnlen strrchr strsep strspn strstr strtod strtol strtold strtoq unsetenv uselocale utime vasprintf getpeereid sysctl swapctl malloc_trim
+for ac_func in asprintf atexit closefrom dup2 eaccess endpwent euidaccess ffsll ftruncate getcwd gethostbyname gethostname getloadavg gettimeofday glob ioperm inet_ntoa isascii memchr memmove memset mkdir mkdtemp munmap newlocale pipe2 ppoll putenv re_comp regcomp select setenv socket strcasecmp strcasestr strchr strcspn strdup strerror strlcat strlcpy strncasecmp strndup strnlen strrchr strsep strspn strstr strtod strtol strtold strtoq unsetenv uselocale utime vasprintf getpeereid sysctl swapctl malloc_trim
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -17924,6 +17938,51 @@ rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
 fi
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if socket() accepts SOCK_NONBLOCK" >&5
+$as_echo_n "checking if socket() accepts SOCK_NONBLOCK... " >&6; }
+if test "$cross_compiling" = yes; then :
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: cross-compile" >&5
+$as_echo "cross-compile" >&6; }
+
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+       #ifdef HAVE_SYS_TYPES_H
+       # include <sys/types.h>
+       #endif
+       #ifdef HAVE_SYS_SOCKET_H
+       # include <sys/socket.h>
+       #endif
+
+int
+main ()
+{
+
+          if (socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0) < 0) {
+             return 1;
+          }
+          return 0;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+$as_echo "#define HAVE_SOCK_NONBLOCK 1" >>confdefs.h
+
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking if we can increase the maximum select-able file descriptor" >&5
 $as_echo_n "checking if we can increase the maximum select-able file descriptor... " >&6; }
 if test "$cross_compiling" = yes; then :

diff --git a/configure.ac b/configure.ac
index e541e33b3aa19e9d9bdc4c675a0a78f426a3c74d..9a016f457b655815a43bce57add2e32ffab3a41d 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -784,7 +784,7 @@ AC_FUNC_STRNLEN
 AC_FUNC_STRTOD
 AC_FUNC_UTIME_NULL
 AC_FUNC_VPRINTF
-AC_CHECK_FUNCS([asprintf atexit closefrom dup2 eaccess endpwent euidaccess ffsll ftruncate getcwd gethostbyname gethostname getloadavg gettimeofday glob ioperm inet_ntoa isascii memchr memmove memset mkdir mkdtemp munmap newlocale ppoll putenv re_comp regcomp select setenv socket strcasecmp strcasestr strchr strcspn strdup strerror strlcat strlcpy strncasecmp strndup strnlen strrchr strsep strspn strstr strtod strtol strtold strtoq unsetenv uselocale utime vasprintf getpeereid sysctl swapctl malloc_trim])
+AC_CHECK_FUNCS([asprintf atexit closefrom dup2 eaccess endpwent euidaccess ffsll ftruncate getcwd gethostbyname gethostname getloadavg gettimeofday glob ioperm inet_ntoa isascii memchr memmove memset mkdir mkdtemp munmap newlocale pipe2 ppoll putenv re_comp regcomp select setenv socket strcasecmp strcasestr strchr strcspn strdup strerror strlcat strlcpy strncasecmp strndup strnlen strrchr strsep strspn strstr strtod strtol strtold strtoq unsetenv uselocale utime vasprintf getpeereid sysctl swapctl malloc_trim])
 
 AC_MSG_CHECKING(for htonll)
 AC_LINK_IFELSE(
@@ -1124,6 +1124,27 @@ AC_RUN_IFELSE(
        AC_MSG_RESULT(unknown)
 )
 
+AC_MSG_CHECKING([if socket() accepts SOCK_NONBLOCK])
+AC_RUN_IFELSE(
+[AC_LANG_PROGRAM([
+       #ifdef HAVE_SYS_TYPES_H
+       # include <sys/types.h>
+       #endif
+       #ifdef HAVE_SYS_SOCKET_H
+       # include <sys/socket.h>
+       #endif
+       ], [
+          if (socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0) < 0) {
+             return 1;
+          }
+          return 0;
+       ])],
+       AC_MSG_RESULT(yes)
+       AC_DEFINE([HAVE_SOCK_NONBLOCK], 1, [Define to 1 if your socket() implementation can accept SOCK_NONBLOCK.]),
+       AC_MSG_RESULT(no),
+       AC_MSG_RESULT(cross-compile)
+)
+
 AC_MSG_CHECKING(if we can increase the maximum select-able file descriptor)
 AC_RUN_IFELSE(
 [AC_LANG_PROGRAM([

diff --git a/include/asterisk/autoconfig.h.in b/include/asterisk/autoconfig.h.in
index d0141fbbb69c40dec414ee6ef336d771879a06d7..72f6ee0b87faf565b524cb69ee53756967c55e3b 100644 (file)
--- a/include/asterisk/autoconfig.h.in
+++ b/include/asterisk/autoconfig.h.in
@@ -609,6 +609,9 @@
 /* Define to indicate presence of the pg_encoding_to_char API. */
 #undef HAVE_PGSQL_pg_encoding_to_char
 
+/* Define to 1 if you have the `pipe2' function. */
+#undef HAVE_PIPE2
+
 /* Define if your system has the PJPROJECT libraries. */
 #undef HAVE_PJPROJECT
 
@@ -877,6 +880,9 @@
 /* Define to 1 if you have the `socket' function. */
 #undef HAVE_SOCKET
 
+/* Define to 1 if your socket() implementation can accept SOCK_NONBLOCK. */
+#undef HAVE_SOCK_NONBLOCK
+
 /* Define to 1 if your system has soxmix application. */
 #undef HAVE_SOXMIX
 

diff --git a/include/asterisk/utils.h b/include/asterisk/utils.h
index f459b319db18de47e41e95a413203414a0c9454e..c0cce98ae232203c5f953227667e1833d6ebf0d8 100644 (file)
--- a/include/asterisk/utils.h
+++ b/include/asterisk/utils.h
@@ -913,6 +913,40 @@ enum ast_fd_flag_operation {
 int __ast_fd_set_flags(int fd, int flags, enum ast_fd_flag_operation op,
        const char *file, int lineno, const char *function);
 
+/*!
+ * \brief Create a non-blocking socket
+ * \since 13.25
+ *
+ * Wrapper around socket(2) that sets the O_NONBLOCK flag on the resulting
+ * socket.
+ *
+ * \details
+ * For parameter and return information, see the man page for
+ * socket(2).
+ */
+#ifdef HAVE_SOCK_NONBLOCK
+# define ast_socket_nonblock(domain, type, protocol) socket((domain), (type) | SOCK_NONBLOCK, (protocol))
+#else
+int ast_socket_nonblock(int domain, int type, int protocol);
+#endif
+
+/*!
+ * \brief Create a non-blocking pipe
+ * \since 13.25
+ *
+ * Wrapper around pipe(2) that sets the O_NONBLOCK flag on the resulting
+ * file descriptors.
+ *
+ * \details
+ * For parameter and return information, see the man page for
+ * pipe(2).
+ */
+#ifdef HAVE_PIPE2
+# define ast_pipe_nonblock(filedes) pipe2((filedes), O_NONBLOCK)
+#else
+int ast_pipe_nonblock(int filedes[2]);
+#endif
+
 /*!
  * \brief Set the current thread's user interface status.
  *

diff --git a/main/alertpipe.c b/main/alertpipe.c
index 7932a7346846ced08e8c0616c78acaaecc842a03..9ff399dfd6c2e10175e9a26d76577232c619958e 100644 (file)
--- a/main/alertpipe.c
+++ b/main/alertpipe.c
@@ -51,6 +51,15 @@ int ast_alertpipe_init(int alert_pipe[2])
 
 #endif
 
+#ifdef HAVE_PIPE2
+
+       if (pipe2(alert_pipe, O_NONBLOCK)) {
+               ast_log(LOG_WARNING, "Failed to create alert pipe: %s\n", strerror(errno));
+               return -1;
+       }
+
+#else
+
        if (pipe(alert_pipe)) {
                ast_log(LOG_WARNING, "Failed to create alert pipe: %s\n", strerror(errno));
                return -1;
@@ -62,6 +71,8 @@ int ast_alertpipe_init(int alert_pipe[2])
                }
        }
 
+#endif
+
        return 0;
 }
 

diff --git a/main/utils.c b/main/utils.c
index a0627634b21227e399c5a3d76751e8ca582125d7..e0b8a6ec029eb95c78b648900bda3545a6496675 100644 (file)
--- a/main/utils.c
+++ b/main/utils.c
@@ -2750,6 +2750,42 @@ int __ast_fd_set_flags(int fd, int flags, enum ast_fd_flag_operation op,
        return 0;
 }
 
+#ifndef HAVE_SOCK_NONBLOCK
+int ast_socket_nonblock(int domain, int type, int protocol)
+{
+       int s = socket(domain, type, protocol);
+       if (s < 0) {
+               return -1;
+       }
+
+       if (ast_fd_set_flags(s, O_NONBLOCK)) {
+               close(s);
+               return -1;
+       }
+
+       return s;
+}
+#endif
+
+#ifndef HAVE_PIPE2
+int ast_pipe_nonblock(int filedes[2])
+{
+       int p = pipe(filedes);
+       if (p < 0) {
+               return -1;
+       }
+
+       if (ast_fd_set_flags(filedes[0], O_NONBLOCK)
+          || ast_fd_set_flags(filedes[1], O_NONBLOCK)) {
+               close(filedes[0]);
+               close(filedes[1]);
+               return -1;
+       }
+
+       return 0;
+}
+#endif
+
 /*!
  * \brief A thread local indicating whether the current thread is a user interface.
  */