* socklen_t data type
@ 2020-06-29 17:23 Eli Zaretskii
2020-06-30 1:07 ` Bruno Haible
0 siblings, 1 reply; 3+ messages in thread
From: Eli Zaretskii @ 2020-06-29 17:23 UTC (permalink / raw)
To: bug-gnulib
Gnulib's sys/socket.h has this:
# if @HAVE_WINSOCK2_H@
/* Include headers needed by the emulation code. */
# include <sys/types.h>
# include <io.h>
# if !GNULIB_defined_socklen_t
typedef int socklen_t;
# define GNULIB_defined_socklen_t 1
# endif
# endif
This unconditionally defines socklen_t on MS-Windows systems as a
signed int data type. Why is this unconditional? This page:
https://pubs.opengroup.org/onlinepubs/007908799/xns/syssocket.h.html
says:
<sys/socket.h> makes available a type, socklen_t, which is an
unsigned opaque integral type of length of at least 32 bits.
So socklen_t could be an unsigned data type, which would then conflict
with the above.
And in fact mingw.org's MinGW recently changed the socklen_t data type
to be unsigned int, which breaks compilation of Gnulib's
sys_socket.c. Is MinGW in error here?
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: socklen_t data type
2020-06-29 17:23 socklen_t data type Eli Zaretskii
@ 2020-06-30 1:07 ` Bruno Haible
2020-06-30 2:29 ` Eli Zaretskii
0 siblings, 1 reply; 3+ messages in thread
From: Bruno Haible @ 2020-06-30 1:07 UTC (permalink / raw)
To: bug-gnulib; +Cc: Rahul Das, Keith Marshall, Eli Zaretskii
[Ccing Keith Marshall as the reporter of <https://savannah.gnu.org/bugs/?57725>]
Hi Eli,
> Gnulib's sys/socket.h has this:
>
> # if @HAVE_WINSOCK2_H@
> /* Include headers needed by the emulation code. */
> # include <sys/types.h>
> # include <io.h>
>
> # if !GNULIB_defined_socklen_t
> typedef int socklen_t;
> # define GNULIB_defined_socklen_t 1
> # endif
>
> # endif
>
> This unconditionally defines socklen_t on MS-Windows systems as a
> signed int data type. Why is this unconditional?
Earlier, it was unconditionally needed.
> This page:
>
> https://pubs.opengroup.org/onlinepubs/007908799/xns/syssocket.h.html
>
> says:
>
> <sys/socket.h> makes available a type, socklen_t, which is an
> unsigned opaque integral type of length of at least 32 bits.
The page you cite is part of SUSv2. It has been superseded by POSIX,
first by the 2004 edition:
https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/socket.h.html
and then by the current edition:
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_socket.h.html
Please update your bookmarks.
> So socklen_t could be an unsigned data type, which would then conflict
> with the above.
>
> And in fact mingw.org's MinGW recently changed the socklen_t data type
> to be unsigned int, which breaks compilation of Gnulib's
> sys_socket.c. Is MinGW in error here?
Looking at the prototypes of the function inet_ntop [1]
it should be 'unsigned int' or 'size_t'.
Looking at the prototypes of the functions connect [2], accept [3], bind [4],
getpeername [5], getsockname [6], getsockopt [7], recvfrom [8], sendto [9],
setsockopt [10]
it should be 'int'.
But regardless how mingw defines 'socklen_t' (as 'int' or as 'unsigned int'),
none of these prototypes is POSIX compliant anyway, since all these prototypes
have the WSAAPI attribute.
So, gnulib should define socklen_t if and only if the system's header don't.
The code which does this is in m4/socklen.m4. I'm therefore applying the patch
below.
[1] https://docs.microsoft.com/en-us/windows/win32/api/ws2tcpip/nf-ws2tcpip-inet_ntop
[2] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-connect
[3] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-accept
[4] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-bind
[5] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-getpeername
[6] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-getsockname
[7] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-getsockopt
[8] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-recvfrom
[9] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-sendto
[10] https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-setsockopt
2020-06-29 Bruno Haible <bruno@clisp.org>
sys_socket: Don't define socklen_t if it is already defined on mingw.
Reported by Keith Marshall <keith.d.marshall@ntlworld.com> in
<https://savannah.gnu.org/bugs/?57725>,
by Rahul Das <bokul_4u@yahoo.com> in
<https://lists.gnu.org/archive/html/bug-gnulib/2020-04/msg00081.html>,
and by Eli Zaretskii <eliz@gnu.org> in
<https://lists.gnu.org/archive/html/bug-gnulib/2020-06/msg00068.html>.
* lib/sys_socket.in.h (socklen_t): Remove definition.
diff --git a/lib/sys_socket.in.h b/lib/sys_socket.in.h
index 948d689..577947d 100644
--- a/lib/sys_socket.in.h
+++ b/lib/sys_socket.in.h
@@ -195,12 +195,7 @@ struct sockaddr_storage
/* Include headers needed by the emulation code. */
# include <sys/types.h>
# include <io.h>
-
-# if !GNULIB_defined_socklen_t
-typedef int socklen_t;
-# define GNULIB_defined_socklen_t 1
-# endif
-
+/* If these headers don't define socklen_t, <config.h> does. */
# endif
/* Rudimentary 'struct msghdr'; this works as long as you don't try to
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: socklen_t data type
2020-06-30 1:07 ` Bruno Haible
@ 2020-06-30 2:29 ` Eli Zaretskii
0 siblings, 0 replies; 3+ messages in thread
From: Eli Zaretskii @ 2020-06-30 2:29 UTC (permalink / raw)
To: Bruno Haible; +Cc: bokul_4u, keith.d.marshall, bug-gnulib
> From: Bruno Haible <bruno@clisp.org>
> Cc: Eli Zaretskii <eliz@gnu.org>, Keith Marshall <keith.d.marshall@ntlworld.com>, Rahul Das <bokul_4u@yahoo.com>
> Date: Tue, 30 Jun 2020 03:07:39 +0200
>
> > <sys/socket.h> makes available a type, socklen_t, which is an
> > unsigned opaque integral type of length of at least 32 bits.
>
> The page you cite is part of SUSv2. It has been superseded by POSIX,
> first by the 2004 edition:
> https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/socket.h.html
> and then by the current edition:
> https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_socket.h.html
>
> Please update your bookmarks.
Right, the "unsigned" part disappeared in the later versions.
> So, gnulib should define socklen_t if and only if the system's header don't.
> The code which does this is in m4/socklen.m4. I'm therefore applying the patch
> below.
Thanks.
^ permalink raw reply [flat|nested] 3+ messages in thread
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2020-06-30 1:07 ` Bruno Haible
2020-06-30 2:29 ` Eli Zaretskii
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