Add `uio.pxd` and update some posix pxds (GH-4526)

* Add a wrapper for posix <sys/uio.h>
* Add a script to generate tests for posix pxds
* Generate `tests/compile/posix_pxds.pyx`
* Update fcntl.pxd to POSIX.1-2017
* Update urls for posix/mman.pxd
* Update urls for posix/resource.pxd
* Add url for posix/select.pxd, and remove a `const`
* Update stat.pxd to POSIX.1-2017
* Update url for posix/wait.pxd

Closes https://github.com/cython/cython/issues/4522

Cython/Includes/posix/fcntl.pxd

-# http://www.opengroup.org/onlinepubs/009695399/basedefs/fcntl.h.html
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/fcntl.h.html
+
+from posix.types cimport mode_t, off_t, pid_t
 
 cdef extern from "<fcntl.h>" nogil:
 
     enum: F_DUPFD
+    enum: F_DUPFD_CLOEXEC
     enum: F_GETFD
     enum: F_SETFD
     enum: F_GETFL
@@ -23,11 +26,14 @@ cdef extern from "<fcntl.h>" nogil:
     enum: SEEK_CUR
     enum: SEEK_END
 
+    enum: O_CLOEXEC
     enum: O_CREAT
     enum: O_DIRECT
+    enum: O_DIRECTORY
     enum: O_EXCL
     enum: O_NOCTTY
     enum: O_TRUNC
+    enum: O_TTY_INIT
 
     enum: O_APPEND
     enum: O_DSYNC
@@ -37,9 +43,17 @@ cdef extern from "<fcntl.h>" nogil:
 
     enum: O_ACCMODE # O_RDONLY|O_WRONLY|O_RDWR
 
+    enum: O_EXEC
     enum: O_RDONLY
     enum: O_WRONLY
     enum: O_RDWR
+    enum: O_SEARCH
+
+    enum: AT_FDCWD
+    enum: AT_EACCESS
+    enum: AT_SYMLINK_NOFOLLOW
+    enum: AT_SYMLINK_FOLLOW
+    enum: AT_REMOVEDIR
 
     enum: S_IFMT
     enum: S_IFBLK
@@ -50,9 +64,12 @@ cdef extern from "<fcntl.h>" nogil:
     enum: S_IFLNK
     enum: S_IFSOCK
 
-    ctypedef int    mode_t
-    ctypedef signed pid_t
-    ctypedef signed off_t
+    enum: POSIX_FADV_DONTNEED
+    enum: POSIX_FADV_NOREUSE
+    enum: POSIX_FADV_NORMAL
+    enum: POSIX_FADV_RANDOM
+    enum: POSIX_FADV_SEQUENTIAL
+    enum: POSIX_FADV_WILLNEED
 
     struct flock:
         short l_type
@@ -61,8 +78,10 @@ cdef extern from "<fcntl.h>" nogil:
         off_t l_len
         pid_t l_pid
 
-    int creat(char *, mode_t)
+    int creat(const char *, mode_t)
     int fcntl(int, int, ...)
-    int open(char *, int, ...)
-    #int open (char *, int, mode_t)
+    int open(const char *, int, ...)
+    int openat(int, const char *, int, ...)
+    int posix_fadvise(int, off_t, off_t, int)
+    int posix_fallocate(int, off_t, off_t)
 

Cython/Includes/posix/mman.pxd

-# https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/mman.h.html
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_mman.h.html
+# https://man7.org/linux/man-pages/man2/mmap.2.html
+# https://www.freebsd.org/cgi/man.cgi?query=mmap&sektion=2
 
 from posix.types cimport off_t, mode_t
 

Cython/Includes/posix/resource.pxd

-# https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/resource.h.html
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_resource.h.html
+# https://man7.org/linux/man-pages/man2/getrusage.2.html
 
 from posix.time  cimport timeval
 from posix.types cimport id_t
@@ -33,6 +34,7 @@ cdef extern from "<sys/resource.h>" nogil:
     cdef struct rusage:
         timeval ru_utime
         timeval ru_stime
+        # Linux-specific
         long    ru_maxrss
         long    ru_ixrss
         long    ru_idrss

Cython/Includes/posix/select.pxd

+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_select.h.html
+
 from .types cimport sigset_t
 from .time cimport timeval, timespec
 
@@ -12,7 +14,7 @@ cdef extern from "<sys/select.h>" nogil:
     void FD_ZERO(fd_set*)
 
     int select(int nfds, fd_set *readfds, fd_set *writefds,
-        fd_set *exceptfds, const timeval *timeout)
+        fd_set *exceptfds, timeval *timeout)
 
     int pselect(int nfds, fd_set *readfds, fd_set *writefds,
         fd_set *exceptfds, const timespec *timeout,

Cython/Includes/posix/stat.pxd

+# https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/stat.h.html
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_stat.h.html
+
 from posix.types cimport (blkcnt_t, blksize_t, dev_t, gid_t, ino_t, mode_t,
                           nlink_t, off_t, time_t, uid_t)
+from posix.time cimport timespec
 
 
 cdef extern from "<sys/stat.h>" nogil:
@@ -14,9 +18,14 @@ cdef extern from "<sys/stat.h>" nogil:
         off_t   st_size
         blksize_t st_blksize
         blkcnt_t st_blocks
+        # POSIX.1-2001
         time_t  st_atime
         time_t  st_mtime
         time_t  st_ctime
+        # POSIX.1-2008
+        timespec st_atim
+        timespec st_mtim
+        timespec st_ctim
 
         # st_birthtime exists on *BSD and OS X.
         # Under Linux, defining it here does not hurt. Compilation under Linux
@@ -25,12 +34,24 @@ cdef extern from "<sys/stat.h>" nogil:
 
 # POSIX prescribes including both <sys/stat.h> and <unistd.h> for these
 cdef extern from "<unistd.h>" nogil:
-    int fchmod(int, mode_t)
     int chmod(const char *, mode_t)
+    int fchmod(int, mode_t)
+    int fchmodat(int, const char *, mode_t, int flags)
 
-    int fstat(int, struct_stat *)
-    int lstat(const char *, struct_stat *)
     int stat(const char *, struct_stat *)
+    int lstat(const char *, struct_stat *)
+    int fstat(int, struct_stat *)
+    int fstatat(int, const char *, struct_stat *, int flags)
+
+    int mkdir(const char *, mode_t)
+    int mkdirat(int, const char *, mode_t)
+    int mkfifo(const char *, mode_t)
+    int mkfifoat(int, const char *, mode_t)
+    int mknod(const char *, mode_t, dev_t)
+    int mknodat(int, const char *, mode_t, dev_t)
+
+    int futimens(int, const timespec *)
+    int utimensat(int, const char *, const timespec *, int flags)
 
     # Macros for st_mode
     mode_t S_ISREG(mode_t)
@@ -69,3 +90,10 @@ cdef extern from "<unistd.h>" nogil:
     mode_t S_IROTH
     mode_t S_IWOTH
     mode_t S_IXOTH
+
+    # test file types
+    bint S_TYPEISMQ(struct_stat *buf)
+    bint S_TYPEISSEM(struct_stat *buf)
+    bint S_TYPEISSHM(struct_stat *buf)
+    bint S_TYPEISTMO(struct_stat *buf)
+

Cython/Includes/posix/uio.pxd

+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_uio.h.html
+
+from posix.types cimport off_t
+
+
+cdef extern from "<sys/uio.h>" nogil:
+
+    cdef struct iovec:
+        void  *iov_base
+        size_t iov_len
+
+    ssize_t readv (int fd, const iovec *iov, int iovcnt)
+    ssize_t writev(int fd, const iovec *iov, int iovcnt)
+
+    # Linux-specific, https://man7.org/linux/man-pages/man2/readv.2.html
+    ssize_t preadv (int fd, const iovec *iov, int iovcnt, off_t offset)
+    ssize_t pwritev(int fd, const iovec *iov, int iovcnt, off_t offset)
+
+    enum: RWF_DSYNC
+    enum: RWF_HIPRI
+    enum: RWF_SYNC
+    enum: RWF_NOWAIT
+    enum: RWF_APPEND
+
+    ssize_t preadv2 (int fd, const iovec *iov, int iovcnt, off_t offset, int flags)
+    ssize_t pwritev2(int fd, const iovec *iov, int iovcnt, off_t offset, int flags)
+

Cython/Includes/posix/wait.pxd

-# https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/wait.h.html
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_wait.h.html
 
 from posix.types cimport pid_t, id_t
 from posix.signal cimport siginfo_t

Tools/gen_tests_for_posix_pxds.py

+#!/usr/bin/python3
+
+from pathlib import Path
+
+PROJECT_ROOT = Path(__file__) / "../.."
+POSIX_PXDS_DIR = PROJECT_ROOT / "Cython/Includes/posix"
+TEST_PATH = PROJECT_ROOT / "tests/compile/posix_pxds.pyx"
+
+def main():
+    datas = [
+        "# tag: posix\n"
+        "# mode: compile\n"
+        "\n"
+        "# This file is generated by `Tools/gen_tests_for_posix_pxds.py`.\n"
+        "\n"
+        "cimport posix\n"
+    ]
+
+    filenames = sorted(map(lambda path: path.name, POSIX_PXDS_DIR.iterdir()))
+
+    for name in filenames:
+        if name == "__init__.pxd":
+            continue
+        if name.endswith(".pxd"):
+            name = name[:-4]
+        else:
+            continue
+
+        s = (
+            "cimport posix.{name}\n"
+            "from posix cimport {name}\n"
+            "from posix.{name} cimport *\n"
+        ).format(name=name)
+
+        datas.append(s)
+
+    with open(TEST_PATH, "w", encoding="utf-8", newline="\n") as f:
+        f.write("\n".join(datas))
+
+if __name__ == "__main__":
+    main()

tests/compile/posix_pxds.pyx

 # tag: posix
 # mode: compile
 
+# This file is generated by `Tools/gen_tests_for_posix_pxds.py`.
+
 cimport posix
 
-cimport posix.unistd
-from posix cimport unistd
-from posix.unistd cimport *
+cimport posix.dlfcn
+from posix cimport dlfcn
+from posix.dlfcn cimport *
 
 cimport posix.fcntl
 from posix cimport fcntl
-from posix.fcntl  cimport *
+from posix.fcntl cimport *
 
-cimport posix.types
-from posix cimport types
-from posix.types cimport *
+cimport posix.ioctl
+from posix cimport ioctl
+from posix.ioctl cimport *
+
+cimport posix.mman
+from posix cimport mman
+from posix.mman cimport *
+
+cimport posix.resource
+from posix cimport resource
+from posix.resource cimport *
+
+cimport posix.select
+from posix cimport select
+from posix.select cimport *
 
 cimport posix.signal
 from posix cimport signal
@@ -31,22 +45,26 @@ cimport posix.stdlib
 from posix cimport stdlib
 from posix.stdlib cimport *
 
+cimport posix.strings
+from posix cimport strings
+from posix.strings cimport *
+
 cimport posix.time
 from posix cimport time
 from posix.time cimport *
 
-cimport posix.resource
-from posix cimport resource
-from posix.resource cimport *
+cimport posix.types
+from posix cimport types
+from posix.types cimport *
+
+cimport posix.uio
+from posix cimport uio
+from posix.uio cimport *
+
+cimport posix.unistd
+from posix cimport unistd
+from posix.unistd cimport *
 
 cimport posix.wait
 from posix cimport wait
 from posix.wait cimport *
-
-cimport posix.mman
-from posix cimport mman
-from posix.mman cimport *
-
-cimport posix.dlfcn
-from posix cimport dlfcn
-from posix.dlfcn cimport *