standards/48339: _POSIX_C_SOURCE and <dev/usb/usb.h> don't mix

[rhialto%falu.nl@localhost]

>Number:         48339
>Category:       standards
>Synopsis:       _POSIX_C_SOURCE and <dev/usb/usb.h> don't mix
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    standards-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Oct 24 19:40:00 +0000 2013
>Originator:     Rhialto
>Release:        NetBSD 6.1.1
>Organization:
        
>Environment:
        
        
System: NetBSD murthe.falu.nl 6.1.1 NetBSD 6.1.1 (MURTHE6.1.1) #4: Sat Sep 28 
12:38:49 CEST 2013 
rhialto%murthe.falu.nl@localhost:/usr/src/sys/arch/amd64/compile/MURTHE6.1.1 
amd64
Architecture: x86_64
Machine: amd64
>Description:
        
        The following small program fails to compile:

$ cat j.c
#define _POSIX_C_SOURCE
#include <dev/usb/usb.h>

int main(int argc, char *argv[])
{
    return 0;
}
$ gcc j.c
In file included from j.c:2:0:
/usr/include/dev/usb/usb.h:663:2: error: expected specifier-qualifier-list 
before 'u_int'
/usr/include/dev/usb/usb.h:675:2: error: expected specifier-qualifier-list 
before 'u_char'
/usr/include/dev/usb/usb.h:735:2: error: expected specifier-qualifier-list 
before 'u_char'
/usr/include/dev/usb/usb.h:739:2: error: expected specifier-qualifier-list 
before 'u_long'
/usr/include/dev/usb/usb.h:743:2: error: expected specifier-qualifier-list 
before 'u_int'
>How-To-Repeat:
        See above.

        Analysis:

        <dev/usb/usb.h> does include <sys/types.h> so one expects u_int,
        u_char and u_long to be defined.

 38 #include <sys/types.h>
...
661 struct usb_full_desc {
662         int     ufd_config_index;
663         u_int   ufd_size;
664         u_char  *ufd_data;
665 };
...
673 struct usb_ctl_report_desc {
674         int     ucrd_size;
675         u_char  ucrd_data[1024];        /* filled data size will vary */
676 };
...

        However, it turns out that <sys/types.h> protects these
        definitions by a _NETBSD_SOURCE:


100 #if defined(_NETBSD_SOURCE)
101 typedef unsigned char   u_char;
102 typedef unsigned short  u_short;
103 typedef unsigned int    u_int;
104 typedef unsigned long   u_long;
...
110 #endif

        Normally, _NETBSD_SOURCE is #defined in <sys/featuretest.h>,
        which is #included from <sys/types.h>

 42 #include <sys/featuretest.h>

        However, _NETBSD_SOURCE is not always defined. If certain
        *_SOURCE symbols are defined, _NETBSD_SOURCE won't be:

 63 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
 64 #define _POSIX_C_SOURCE 1L
 65 #endif
 66 
 67 #if !defined(_ANSI_SOURCE) && !defined(_POSIX_C_SOURCE) && \
 68     !defined(_XOPEN_SOURCE) && !defined(_NETBSD_SOURCE)
 69 #define _NETBSD_SOURCE 1
 70 #endif

>Fix:
        Probably <dev/usb/usb.h> should use more (standard or at least
        certain to be defined) types, such as uint{8,16,32}_t or plain
        unsigned char, unsigned int and unsigned long.

        It uses both {u,}int{8,16,32}_t and char,int,long in plenty of
        places already.

-Olaf.
-- 
___ Olaf 'Rhialto' Seibert  -- The Doctor: No, 'eureka' is Greek for
\X/ rhialto/at/xs4all.nl    -- 'this bath is too hot.'

>Unformatted: