bpo-31368: Expose preadv and pwritev in the os module (#5239)

Doc/library/os.rst

@@ -1102,6 +1102,45 @@ or `the MSDN <https://msdn.microsoft.com/en-us/library/z0kc8e3z.aspx>`_ on Windo
    .. versionadded:: 3.3
 
 
+.. function:: pwritev(fd, buffers, offset, flags=0)
+
+   Combines the functionality of :func:`os.writev` and :func:`os.pwrite`. It
+   writes the contents of *buffers* to file descriptor *fd* at offset *offset*.
+   *buffers* must be a sequence of :term:`bytes-like objects <bytes-like object>`.
+   Buffers are processed in array order. Entire contents of first buffer is written
+   before proceeding to second, and so on. The operating system may set a limit
+   (sysconf() value SC_IOV_MAX) on the number of buffers that can be used.
+   :func:`~os.pwritev` writes the contents of each object to the file descriptor
+   and returns the total number of bytes written.
+
+   The *flags* argument contains a bitwise OR of zero or more of the following
+   flags:
+
+   - RWF_DSYNC
+   - RWF_SYNC
+
+   Using non-zero flags requires Linux 4.7 or newer.
+
+   Availability: Linux (version 2.6.30), FreeBSD 6.0 and newer,
+   OpenBSD (version 2.7 and newer).
+
+   .. versionadded:: 3.7
+
+.. data:: RWF_DSYNC (since Linux 4.7)
+   Provide a per-write equivalent of the O_DSYNC open(2) flag. This flag
+   is meaningful only for pwritev2(), and its effect applies only to the
+   data range written by the system call.
+
+   .. versionadded:: 3.7
+
+.. data:: RWF_SYNC (since Linux 4.7)
+   Provide a per-write equivalent of the O_SYNC open(2) flag. This flag is
+   meaningful only for pwritev2(), and its effect applies only to the data
+   range written by the system call.
+
+   .. versionadded:: 3.7
+
+
 .. function:: read(fd, n)
 
    Read at most *n* bytes from file descriptor *fd*. Return a bytestring containing the
@@ -1196,6 +1235,51 @@ or `the MSDN <https://msdn.microsoft.com/en-us/library/z0kc8e3z.aspx>`_ on Windo
    .. versionadded:: 3.3
 
 
+.. function:: preadv(fd, buffers, offset, flags=0)
+
+   Combines the functionality of :func:`os.readv` and :func:`os.pread`. It
+   reads from a file descriptor *fd* into a number of mutable :term:`bytes-like
+   objects <bytes-like object>` *buffers*. As :func:`os.readv`, it will transfer
+   data into each buffer until it is full and then move on to the next buffer in
+   the sequence to hold the rest of the data. Its fourth argument, *offset*,
+   specifies the file offset at which the input operation is to be performed.
+   :func:`~os.preadv` return the total number of bytes read (which can be less than
+   the total capacity of all the objects).
+
+   The flags argument contains a bitwise OR of zero or more of the following
+   flags:
+
+   - RWF_HIPRI
+   - RWF_NOWAIT
+
+   Using non-zero flags requires Linux 4.6 or newer.
+
+   Availability: Linux (version 2.6.30), FreeBSD 6.0 and newer,
+   OpenBSD (version 2.7 and newer).
+
+   .. versionadded:: 3.7
+
+
+.. data:: RWF_HIPRI (since Linux 4.6)
+   High priority read/write. Allows block-based filesystems to use polling
+   of the device, which provides lower latency, but may use additional
+   resources. (Currently, this feature is usable only on a file descriptor
+   opened using the O_DIRECT flag.)
+
+   .. versionadded:: 3.7
+
+
+.. data:: RWF_NOWAIT (since Linux 4.14)
+   Do not wait for data which is not immediately available. If this flag
+   is  specified, the preadv2() system call will return instantly
+   if it would have to read data from the backing storage or wait for a lock.
+   If some data was successfully read, it will return the number of bytes
+   read. If no bytes were read, it will return -1 and set errno to EAGAIN.
+   Currently, this flag is meaningful only for preadv2().
+
+   .. versionadded:: 3.7
+
+
 .. function:: tcgetpgrp(fd)
 
    Return the process group associated with the terminal given by *fd* (an open

Lib/test/test_posix.py

@@ -272,6 +272,28 @@ class PosixTester(unittest.TestCase):
         finally:
             os.close(fd)
 
+    @unittest.skipUnless(hasattr(posix, 'preadv'), "test needs posix.preadv()")
+    def test_preadv(self):
+        fd = os.open(support.TESTFN, os.O_RDWR | os.O_CREAT)
+        try:
+            os.write(fd, b'test1tt2t3t5t6t6t8')
+            buf = [bytearray(i) for i in [5, 3, 2]]
+            self.assertEqual(posix.preadv(fd, buf, 3), 10)
+            self.assertEqual([b't1tt2', b't3t', b'5t'], list(buf))
+        finally:
+            os.close(fd)
+
+    @unittest.skipUnless(hasattr(posix, 'RWF_HIPRI'), "test needs posix.RWF_HIPRI")
+    def test_preadv_flags(self):
+        fd = os.open(support.TESTFN, os.O_RDWR | os.O_CREAT)
+        try:
+            os.write(fd, b'test1tt2t3t5t6t6t8')
+            buf = [bytearray(i) for i in [5, 3, 2]]
+            self.assertEqual(posix.preadv(fd, buf, 3, os.RWF_HIPRI), 10)
+            self.assertEqual([b't1tt2', b't3t', b'5t'], list(buf))
+        finally:
+            os.close(fd)
+
     @unittest.skipUnless(hasattr(posix, 'pwrite'), "test needs posix.pwrite()")
     def test_pwrite(self):
         fd = os.open(support.TESTFN, os.O_RDWR | os.O_CREAT)
@@ -283,6 +305,34 @@ class PosixTester(unittest.TestCase):
         finally:
             os.close(fd)
 
+    @unittest.skipUnless(hasattr(posix, 'pwritev'), "test needs posix.pwritev()")
+    def test_pwritev(self):
+        fd = os.open(support.TESTFN, os.O_RDWR | os.O_CREAT)
+        try:
+            os.write(fd, b"xx")
+            os.lseek(fd, 0, os.SEEK_SET)
+            n = os.pwritev(fd, [b'test1', b'tt2', b't3'], 2)
+            self.assertEqual(n, 10)
+
+            os.lseek(fd, 0, os.SEEK_SET)
+            self.assertEqual(b'xxtest1tt2t3', posix.read(fd, 100))
+        finally:
+            os.close(fd)
+
+    @unittest.skipUnless(hasattr(posix, 'os.RWF_SYNC'), "test needs os.RWF_SYNC")
+    def test_pwritev_flags(self):
+        fd = os.open(support.TESTFN, os.O_RDWR | os.O_CREAT)
+        try:
+            os.write(fd,b"xx")
+            os.lseek(fd, 0, os.SEEK_SET)
+            n = os.pwritev(fd, [b'test1', b'tt2', b't3'], 2, os.RWF_SYNC)
+            self.assertEqual(n, 10)
+
+            os.lseek(fd, 0, os.SEEK_SET)
+            self.assertEqual(b'xxtest1tt2', posix.read(fd, 100))
+        finally:
+            os.close(fd)
+
     @unittest.skipUnless(hasattr(posix, 'posix_fallocate'),
         "test needs posix.posix_fallocate()")
     def test_posix_fallocate(self):

Misc/NEWS.d/next/Core and Builtins/2018-01-19-01-54-22.bpo-31368.kzKqUR.rst

@@ -0,0 +1 @@
+Expose preadv and pwritev system calls in the os module. Patch by Pablo Galindo

Modules/clinic/posixmodule.c.h

@@ -3705,6 +3705,61 @@ exit:
 
 #endif /* defined(HAVE_PREAD) */
 
+#if (defined(HAVE_PREADV) || defined (HAVE_PREADV2))
+
+PyDoc_STRVAR(os_preadv__doc__,
+"preadv($module, fd, buffers, offset, flags=0, /)\n"
+"--\n"
+"\n"
+"Reads from a file descriptor into a number of mutable bytes-like objects.\n"
+"\n"
+"Combines the functionality of readv() and pread(). As readv(), it will\n"
+"transfer data into each buffer until it is full and then move on to the next\n"
+"buffer in the sequence to hold the rest of the data. Its fourth argument,\n"
+"specifies the file offset at which the input operation is to be performed. It\n"
+"will return the total number of bytes read (which can be less than the total\n"
+"capacity of all the objects).\n"
+"\n"
+"The flags argument contains a bitwise OR of zero or more of the following flags:\n"
+"\n"
+"- RWF_HIPRI\n"
+"- RWF_NOWAIT\n"
+"\n"
+"Using non-zero flags requires Linux 4.6 or newer.");
+
+#define OS_PREADV_METHODDEF    \
+    {"preadv", (PyCFunction)os_preadv, METH_FASTCALL, os_preadv__doc__},
+
+static Py_ssize_t
+os_preadv_impl(PyObject *module, int fd, PyObject *buffers, Py_off_t offset,
+               int flags);
+
+static PyObject *
+os_preadv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
+{
+    PyObject *return_value = NULL;
+    int fd;
+    PyObject *buffers;
+    Py_off_t offset;
+    int flags = 0;
+    Py_ssize_t _return_value;
+
+    if (!_PyArg_ParseStack(args, nargs, "iOO&|i:preadv",
+        &fd, &buffers, Py_off_t_converter, &offset, &flags)) {
+        goto exit;
+    }
+    _return_value = os_preadv_impl(module, fd, buffers, offset, flags);
+    if ((_return_value == -1) && PyErr_Occurred()) {
+        goto exit;
+    }
+    return_value = PyLong_FromSsize_t(_return_value);
+
+exit:
+    return return_value;
+}
+
+#endif /* (defined(HAVE_PREADV) || defined (HAVE_PREADV2)) */
+
 PyDoc_STRVAR(os_write__doc__,
 "write($module, fd, data, /)\n"
 "--\n"
@@ -3963,6 +4018,61 @@ exit:
 
 #endif /* defined(HAVE_PWRITE) */
 
+#if (defined(HAVE_PWRITEV) || defined (HAVE_PWRITEV2))
+
+PyDoc_STRVAR(os_pwritev__doc__,
+"pwritev($module, fd, buffers, offset, flags=0, /)\n"
+"--\n"
+"\n"
+"Writes the contents of bytes-like objects to a file descriptor at a given offset.\n"
+"\n"
+"Combines the functionality of writev() and pwrite(). All buffers must be a sequence\n"
+"of bytes-like objects. Buffers are processed in array order. Entire contents of first\n"
+"buffer is written before proceeding to second, and so on. The operating system may\n"
+"set a limit (sysconf() value SC_IOV_MAX) on the number of buffers that can be used.\n"
+"This function writes the contents of each object to the file descriptor and returns\n"
+"the total number of bytes written.\n"
+"\n"
+"The flags argument contains a bitwise OR of zero or more of the following flags:\n"
+"\n"
+"- RWF_DSYNC\n"
+"- RWF_SYNC\n"
+"\n"
+"Using non-zero flags requires Linux 4.7 or newer.");
+
+#define OS_PWRITEV_METHODDEF    \
+    {"pwritev", (PyCFunction)os_pwritev, METH_FASTCALL, os_pwritev__doc__},
+
+static Py_ssize_t
+os_pwritev_impl(PyObject *module, int fd, PyObject *buffers, Py_off_t offset,
+                int flags);
+
+static PyObject *
+os_pwritev(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
+{
+    PyObject *return_value = NULL;
+    int fd;
+    PyObject *buffers;
+    Py_off_t offset;
+    int flags = 0;
+    Py_ssize_t _return_value;
+
+    if (!_PyArg_ParseStack(args, nargs, "iOO&|i:pwritev",
+        &fd, &buffers, Py_off_t_converter, &offset, &flags)) {
+        goto exit;
+    }
+    _return_value = os_pwritev_impl(module, fd, buffers, offset, flags);
+    if ((_return_value == -1) && PyErr_Occurred()) {
+        goto exit;
+    }
+    return_value = PyLong_FromSsize_t(_return_value);
+
+exit:
+    return return_value;
+}
+
+#endif /* (defined(HAVE_PWRITEV) || defined (HAVE_PWRITEV2)) */
+
 #if defined(HAVE_MKFIFO)
 
 PyDoc_STRVAR(os_mkfifo__doc__,
@@ -6239,6 +6349,10 @@ exit:
     #define OS_PREAD_METHODDEF
 #endif /* !defined(OS_PREAD_METHODDEF) */
 
+#ifndef OS_PREADV_METHODDEF
+    #define OS_PREADV_METHODDEF
+#endif /* !defined(OS_PREADV_METHODDEF) */
+
 #ifndef OS_PIPE_METHODDEF
     #define OS_PIPE_METHODDEF
 #endif /* !defined(OS_PIPE_METHODDEF) */
@@ -6255,6 +6369,10 @@ exit:
     #define OS_PWRITE_METHODDEF
 #endif /* !defined(OS_PWRITE_METHODDEF) */
 
+#ifndef OS_PWRITEV_METHODDEF
+    #define OS_PWRITEV_METHODDEF
+#endif /* !defined(OS_PWRITEV_METHODDEF) */
+
 #ifndef OS_MKFIFO_METHODDEF
     #define OS_MKFIFO_METHODDEF
 #endif /* !defined(OS_MKFIFO_METHODDEF) */
@@ -6410,4 +6528,4 @@ exit:
 #ifndef OS_GETRANDOM_METHODDEF
     #define OS_GETRANDOM_METHODDEF
 #endif /* !defined(OS_GETRANDOM_METHODDEF) */
-/*[clinic end generated code: output=6345053cd5992caf input=a9049054013a1b77]*/
+/*[clinic end generated code: output=06ace805893aa10c input=a9049054013a1b77]*/

Modules/posixmodule.c

@@ -8163,6 +8163,94 @@ os_pread_impl(PyObject *module, int fd, int length, Py_off_t offset)
 }
 #endif /* HAVE_PREAD */
 
+#if defined(HAVE_PREADV) || defined (HAVE_PREADV2)
+/*[clinic input]
+os.preadv -> Py_ssize_t
+
+    fd: int
+    buffers: object
+    offset: Py_off_t
+    flags: int = 0
+    /
+
+Reads from a file descriptor into a number of mutable bytes-like objects.
+
+Combines the functionality of readv() and pread(). As readv(), it will
+transfer data into each buffer until it is full and then move on to the next
+buffer in the sequence to hold the rest of the data. Its fourth argument,
+specifies the file offset at which the input operation is to be performed. It
+will return the total number of bytes read (which can be less than the total
+capacity of all the objects).
+
+The flags argument contains a bitwise OR of zero or more of the following flags:
+
+- RWF_HIPRI
+- RWF_NOWAIT
+
+Using non-zero flags requires Linux 4.6 or newer.
+[clinic start generated code]*/
+
+static Py_ssize_t
+os_preadv_impl(PyObject *module, int fd, PyObject *buffers, Py_off_t offset,
+               int flags)
+/*[clinic end generated code: output=26fc9c6e58e7ada5 input=4173919dc1f7ed99]*/
+{
+    Py_ssize_t cnt, n;
+    int async_err = 0;
+    struct iovec *iov;
+    Py_buffer *buf;
+
+    if (!PySequence_Check(buffers)) {
+        PyErr_SetString(PyExc_TypeError,
+            "preadv2() arg 2 must be a sequence");
+        return -1;
+    }
+
+    cnt = PySequence_Size(buffers);
+    if (cnt < 0) {
+        return -1;
+    }
+
+#ifndef HAVE_PREADV2
+    if(flags != 0) {
+        argument_unavailable_error("preadv2", "flags");
+        return -1;
+    }
+#endif
+
+    if (iov_setup(&iov, &buf, buffers, cnt, PyBUF_WRITABLE) < 0) {
+        return -1;
+    }
+#ifdef HAVE_PREADV2
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        _Py_BEGIN_SUPPRESS_IPH
+        n = preadv2(fd, iov, cnt, offset, flags);
+        _Py_END_SUPPRESS_IPH
+        Py_END_ALLOW_THREADS
+    } while (n < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
+#else
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        _Py_BEGIN_SUPPRESS_IPH
+        n = preadv(fd, iov, cnt, offset);
+        _Py_END_SUPPRESS_IPH
+        Py_END_ALLOW_THREADS
+    } while (n < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
+#endif
+
+    iov_cleanup(iov, buf, cnt);
+    if (n < 0) {
+        if (!async_err) {
+            posix_error();
+        }
+        return -1;
+    }
+
+    return n;
+}
+#endif /* HAVE_PREADV */
+
 
 /*[clinic input]
 os.write -> Py_ssize_t
@@ -8613,6 +8701,97 @@ os_pwrite_impl(PyObject *module, int fd, Py_buffer *buffer, Py_off_t offset)
 }
 #endif /* HAVE_PWRITE */
 
+#if defined(HAVE_PWRITEV) || defined (HAVE_PWRITEV2)
+/*[clinic input]
+os.pwritev -> Py_ssize_t
+
+    fd: int
+    buffers: object
+    offset: Py_off_t
+    flags: int = 0
+    /
+
+Writes the contents of bytes-like objects to a file descriptor at a given offset.
+
+Combines the functionality of writev() and pwrite(). All buffers must be a sequence
+of bytes-like objects. Buffers are processed in array order. Entire contents of first
+buffer is written before proceeding to second, and so on. The operating system may
+set a limit (sysconf() value SC_IOV_MAX) on the number of buffers that can be used.
+This function writes the contents of each object to the file descriptor and returns
+the total number of bytes written.
+
+The flags argument contains a bitwise OR of zero or more of the following flags:
+
+- RWF_DSYNC
+- RWF_SYNC
+
+Using non-zero flags requires Linux 4.7 or newer.
+[clinic start generated code]*/
+
+static Py_ssize_t
+os_pwritev_impl(PyObject *module, int fd, PyObject *buffers, Py_off_t offset,
+                int flags)
+/*[clinic end generated code: output=e3dd3e9d11a6a5c7 input=803dc5ddbf0cfd3b]*/
+{
+    Py_ssize_t cnt;
+    Py_ssize_t result;
+    int async_err = 0;
+    struct iovec *iov;
+    Py_buffer *buf;
+
+    if (!PySequence_Check(buffers)) {
+        PyErr_SetString(PyExc_TypeError,
+            "pwritev() arg 2 must be a sequence");
+        return -1;
+    }
+
+    cnt = PySequence_Size(buffers);
+    if (cnt < 0) {
+        return -1;
+    }
+
+#ifndef HAVE_PWRITEV2
+    if(flags != 0) {
+        argument_unavailable_error("pwritev2", "flags");
+        return -1;
+    }
+#endif
+
+    if (iov_setup(&iov, &buf, buffers, cnt, PyBUF_SIMPLE) < 0) {
+        return -1;
+    }
+#ifdef HAVE_PWRITEV2
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        _Py_BEGIN_SUPPRESS_IPH
+        result = pwritev2(fd, iov, cnt, offset, flags);
+        _Py_END_SUPPRESS_IPH
+        Py_END_ALLOW_THREADS
+    } while (result < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
+#else
+    do {
+        Py_BEGIN_ALLOW_THREADS
+        _Py_BEGIN_SUPPRESS_IPH
+        result = pwritev(fd, iov, cnt, offset);
+        _Py_END_SUPPRESS_IPH
+        Py_END_ALLOW_THREADS
+    } while (result < 0 && errno == EINTR && !(async_err = PyErr_CheckSignals()));
+#endif
+
+    iov_cleanup(iov, buf, cnt);
+    if (result < 0) {
+        if (!async_err) {
+            posix_error();
+        }
+        return -1;
+    }
+
+    return result;
+}
+#endif /* HAVE_PWRITEV */
+
+
+
 
 #ifdef HAVE_MKFIFO
 /*[clinic input]
@@ -12506,9 +12685,11 @@ static PyMethodDef posix_methods[] = {
     OS_READ_METHODDEF
     OS_READV_METHODDEF
     OS_PREAD_METHODDEF
+    OS_PREADV_METHODDEF
     OS_WRITE_METHODDEF
     OS_WRITEV_METHODDEF
     OS_PWRITE_METHODDEF
+    OS_PWRITEV_METHODDEF
 #ifdef HAVE_SENDFILE
     {"sendfile",        (PyCFunction)posix_sendfile, METH_VARARGS | METH_KEYWORDS,
                             posix_sendfile__doc__},
@@ -12953,6 +13134,19 @@ all_ins(PyObject *m)
     if (PyModule_AddIntMacro(m, F_TEST)) return -1;
 #endif
 
+#ifdef RWF_DSYNC
+    if (PyModule_AddIntConstant(m, "RWF_DSYNC", RWF_DSYNC)) return -1;
+#endif
+#ifdef RWF_HIPRI
+    if (PyModule_AddIntConstant(m, "RWF_HIPRI", RWF_HIPRI)) return -1;
+#endif
+#ifdef RWF_SYNC
+    if (PyModule_AddIntConstant(m, "RWF_SYNC", RWF_SYNC)) return -1;
+#endif
+#ifdef RWF_NOWAIT
+    if (PyModule_AddIntConstant(m, "RWF_NOWAIT", RWF_NOWAIT)) return -1;
+#endif
+
 #ifdef HAVE_SPAWNV
     if (PyModule_AddIntConstant(m, "P_WAIT", _P_WAIT)) return -1;
     if (PyModule_AddIntConstant(m, "P_NOWAIT", _P_NOWAIT)) return -1;

aclocal.m4

@@ -13,7 +13,7 @@
 
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
 # pkg.m4 - Macros to locate and utilise pkg-config.   -*- Autoconf -*-
-# serial 11 (pkg-config-0.29.1)
+# serial 12 (pkg-config-0.29.2)
 
 dnl Copyright © 2004 Scott James Remnant <scott@netsplit.com>.
 dnl Copyright © 2012-2015 Dan Nicholson <dbn.lists@gmail.com>
@@ -55,7 +55,7 @@ dnl
 dnl See the "Since" comment for each macro you use to see what version
 dnl of the macros you require.
 m4_defun([PKG_PREREQ],
-[m4_define([PKG_MACROS_VERSION], [0.29.1])
+[m4_define([PKG_MACROS_VERSION], [0.29.2])
 m4_if(m4_version_compare(PKG_MACROS_VERSION, [$1]), -1,
     [m4_fatal([pkg.m4 version $1 or higher is required but ]PKG_MACROS_VERSION[ found])])
 ])dnl PKG_PREREQ
@@ -156,7 +156,7 @@ AC_ARG_VAR([$1][_CFLAGS], [C compiler flags for $1, overriding pkg-config])dnl
 AC_ARG_VAR([$1][_LIBS], [linker flags for $1, overriding pkg-config])dnl
 
 pkg_failed=no
-AC_MSG_CHECKING([for $1])
+AC_MSG_CHECKING([for $2])
 
 _PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
 _PKG_CONFIG([$1][_LIBS], [libs], [$2])
@@ -166,11 +166,11 @@ and $1[]_LIBS to avoid the need to call pkg-config.
 See the pkg-config man page for more details.])
 
 if test $pkg_failed = yes; then
-   	AC_MSG_RESULT([no])
+        AC_MSG_RESULT([no])
         _PKG_SHORT_ERRORS_SUPPORTED
         if test $_pkg_short_errors_supported = yes; then
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "$2" 2>&1`
-        else 
+        else
 	        $1[]_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "$2" 2>&1`
         fi
 	# Put the nasty error message in config.log where it belongs
@@ -187,7 +187,7 @@ installed software in a non-standard prefix.
 _PKG_TEXT])[]dnl
         ])
 elif test $pkg_failed = untried; then
-     	AC_MSG_RESULT([no])
+        AC_MSG_RESULT([no])
 	m4_default([$4], [AC_MSG_FAILURE(
 [The pkg-config script could not be found or is too old.  Make sure it
 is in your PATH or set the PKG_CONFIG environment variable to the full
@@ -288,72 +288,4 @@ AS_VAR_COPY([$1], [pkg_cv_][$1])
 AS_VAR_IF([$1], [""], [$5], [$4])dnl
 ])dnl PKG_CHECK_VAR
 
-dnl PKG_WITH_MODULES(VARIABLE-PREFIX, MODULES,
-dnl   [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND],
-dnl   [DESCRIPTION], [DEFAULT])
-dnl ------------------------------------------
-dnl
-dnl Prepare a "--with-" configure option using the lowercase
-dnl [VARIABLE-PREFIX] name, merging the behaviour of AC_ARG_WITH and
-dnl PKG_CHECK_MODULES in a single macro.
-AC_DEFUN([PKG_WITH_MODULES],
-[
-m4_pushdef([with_arg], m4_tolower([$1]))
-
-m4_pushdef([description],
-           [m4_default([$5], [build with ]with_arg[ support])])
-
-m4_pushdef([def_arg], [m4_default([$6], [auto])])
-m4_pushdef([def_action_if_found], [AS_TR_SH([with_]with_arg)=yes])
-m4_pushdef([def_action_if_not_found], [AS_TR_SH([with_]with_arg)=no])
-
-m4_case(def_arg,
-            [yes],[m4_pushdef([with_without], [--without-]with_arg)],
-            [m4_pushdef([with_without],[--with-]with_arg)])
-
-AC_ARG_WITH(with_arg,
-     AS_HELP_STRING(with_without, description[ @<:@default=]def_arg[@:>@]),,
-    [AS_TR_SH([with_]with_arg)=def_arg])
-
-AS_CASE([$AS_TR_SH([with_]with_arg)],
-            [yes],[PKG_CHECK_MODULES([$1],[$2],$3,$4)],
-            [auto],[PKG_CHECK_MODULES([$1],[$2],
-                                        [m4_n([def_action_if_found]) $3],
-                                        [m4_n([def_action_if_not_found]) $4])])
-
-m4_popdef([with_arg])
-m4_popdef([description])
-m4_popdef([def_arg])
-
-])dnl PKG_WITH_MODULES
-
-dnl PKG_HAVE_WITH_MODULES(VARIABLE-PREFIX, MODULES,
-dnl   [DESCRIPTION], [DEFAULT])
-dnl -----------------------------------------------
-dnl
-dnl Convenience macro to trigger AM_CONDITIONAL after PKG_WITH_MODULES
-dnl check._[VARIABLE-PREFIX] is exported as make variable.
-AC_DEFUN([PKG_HAVE_WITH_MODULES],
-[
-PKG_WITH_MODULES([$1],[$2],,,[$3],[$4])
-
-AM_CONDITIONAL([HAVE_][$1],
-               [test "$AS_TR_SH([with_]m4_tolower([$1]))" = "yes"])
-])dnl PKG_HAVE_WITH_MODULES
-
-dnl PKG_HAVE_DEFINE_WITH_MODULES(VARIABLE-PREFIX, MODULES,
-dnl   [DESCRIPTION], [DEFAULT])
-dnl ------------------------------------------------------
-dnl
-dnl Convenience macro to run AM_CONDITIONAL and AC_DEFINE after
-dnl PKG_WITH_MODULES check. HAVE_[VARIABLE-PREFIX] is exported as make
-dnl and preprocessor variable.
-AC_DEFUN([PKG_HAVE_DEFINE_WITH_MODULES],
-[
-PKG_HAVE_WITH_MODULES([$1],[$2],[$3],[$4])
-
-AS_IF([test "$AS_TR_SH([with_]m4_tolower([$1]))" = "yes"],
-        [AC_DEFINE([HAVE_][$1], 1, [Enable ]m4_tolower([$1])[ support])])
-])dnl PKG_HAVE_DEFINE_WITH_MODULES
-
 m4_include([m4/ax_check_openssl.m4])

configure

@@ -11197,8 +11197,8 @@ for ac_func in alarm accept4 setitimer getitimer bind_textdomain_codeset chown \
  initgroups kill killpg lchmod lchown lockf linkat lstat lutimes mmap \
  memrchr mbrtowc mkdirat mkfifo \
  mkfifoat mknod mknodat mktime mremap nice openat pathconf pause pipe2 plock poll \
- posix_fallocate posix_fadvise pread \
+ posix_fallocate posix_fadvise pread preadv preadv2 \
- pthread_init pthread_kill putenv pwrite readlink readlinkat readv realpath renameat \
+ pthread_init pthread_kill putenv pwrite pwritev pwritev2 readlink readlinkat readv realpath renameat \
  sem_open sem_timedwait sem_getvalue sem_unlink sendfile setegid seteuid \
  setgid sethostname \
  setlocale setregid setreuid setresuid setresgid setsid setpgid setpgrp setpriority setuid setvbuf \

configure.ac

@@ -3431,8 +3431,8 @@ AC_CHECK_FUNCS(alarm accept4 setitimer getitimer bind_textdomain_codeset chown \
  initgroups kill killpg lchmod lchown lockf linkat lstat lutimes mmap \
  memrchr mbrtowc mkdirat mkfifo \
  mkfifoat mknod mknodat mktime mremap nice openat pathconf pause pipe2 plock poll \
- posix_fallocate posix_fadvise pread \
+ posix_fallocate posix_fadvise pread preadv preadv2 \
- pthread_init pthread_kill putenv pwrite readlink readlinkat readv realpath renameat \
+ pthread_init pthread_kill putenv pwrite pwritev pwritev2 readlink readlinkat readv realpath renameat \
  sem_open sem_timedwait sem_getvalue sem_unlink sendfile setegid seteuid \
  setgid sethostname \
  setlocale setregid setreuid setresuid setresgid setsid setpgid setpgrp setpriority setuid setvbuf \

pyconfig.h.in

@@ -710,6 +710,12 @@
 /* Define to 1 if you have the `pread' function. */
 #undef HAVE_PREAD
 
+/* Define to 1 if you have the `preadv' function. */
+#undef HAVE_PREADV
+
+/* Define to 1 if you have the `preadv2' function. */
+#undef HAVE_PREADV2
+
 /* Define if you have the 'prlimit' functions. */
 #undef HAVE_PRLIMIT
 
@@ -746,6 +752,12 @@
 /* Define to 1 if you have the `pwrite' function. */
 #undef HAVE_PWRITE
 
+/* Define to 1 if you have the `pwritev' function. */
+#undef HAVE_PWRITEV
+
+/* Define to 1 if you have the `pwritev2' function. */
+#undef HAVE_PWRITEV2
+
 /* Define to 1 if you have the `readlink' function. */
 #undef HAVE_READLINK