Re: Compiler warning under cygwin/mingw
On 29/02/16 12:32, Ramsay Jones wrote:
Show 25 quoted lines
>
>
> On 29/02/16 10:40, Torsten Bögershausen wrote:
>> That compiles OK, thanks.
>>
>>
>> Sorry for high-jacking this thread, but while compiling under CYGWIN,
>> found one warning:
>>
>> LINK git-credential-store.exe
>> CC daemon.o
>> daemon.c: In function ‘drop_privileges’:
>> daemon.c:1136:15: warning: implicit declaration of function ‘initgroups’ [-Wimplicit-function-declaration]
>> if (cred && (initgroups(cred->pass->pw_name, cred->gid) ||
>
> Yeah, this has been there for a while - except it depends on which version
> of the header files you have. (Some may not see the warning).
>
> I have 'fixed' this twice before, then updated my installation and
> a change to the system headers broke it again! (The headers are
> currently 'broken'). So, I got tired of fixing it up and have left
> it a while - you never know a new update may fix it! ;-)
>
> [I personally don't use the git daemon on cygwin, so I don't know
> if this a problem in practice.]
BTW, I forgot to mention that I have had a patch in my local repo for ages which addresses this issue. However, although this patch fixes the problem for me, with the header files I currently have installed, it would just as easily _introduce_ this warning for those that don't currently see it! ;-)
I suppose that I could send a patch which sets NO_INITGROUPS in the Makefile, until the system header files are fixed. What do you think?
The correct solution is to fix the <grp.h> header file. I have been a bit reluctant to tackle that, because I'm not familiar with the cygwin project development process. Since Newlib is an upstream project to cygwin, should I go there first/instead?
Anyway, I had a quick squint at the header and I think it needs to be changed something like the diff below. (I've also attached the new grp.h file).
[Note: I didn't know what to do about _PATH_GROUP, setgrfile(), group_from_gid() and setgroupent(), so I punted on those!]
Now, If only we knew someone who could try introducing such a fix to the cygwin project ...
ATB, Ramsay Jones -- >8 --
diff --git a/usr/include/grp.h b/grp.h
index c3a5a67..f2f1902 100644
--- a/usr/include/grp.h
+++ b/grp.h
@@ -67,25 +67,27 @@ extern "C" {
#ifndef __INSIDE_CYGWIN__
struct group *getgrgid (gid_t);
struct group *getgrnam (const char *);
+#if defined __POSIX_VISIBLE || defined __BSD_VISIBLE
int getgrnam_r (const char *, struct group *,
char *, size_t, struct group **);
int getgrgid_r (gid_t, struct group *,
char *, size_t, struct group **);
-#ifndef _POSIX_SOURCE
-struct group *getgrent (void);
+#endif
+#if defined __BSD_VISIBLE || defined _XOPEN_SOURCE_EXTENDED
void setgrent (void);
+#if __XSI_VISIBLE >= 700
+struct group *getgrent (void);
void endgrent (void);
+#endif
+#endif
+#if defined __BSD_VISIBLE
+int initgroups (const char *, gid_t);
+#endif
#ifndef __CYGWIN__
-void setgrfile (const char *);
-#endif /* !__CYGWIN__ */
-#ifndef _XOPEN_SOURCE
-#ifndef __CYGWIN__
+void setgrfile (const char *); /* 4.3BSD-Reno & Minix */
char *group_from_gid (gid_t, int);
-int setgroupent (int);
+int setgroupent (int); /* 4.3BSD-Reno & Mac OS X */
#endif /* !__CYGWIN__ */
-int initgroups (const char *, gid_t);
-#endif /* !_XOPEN_SOURCE */
-#endif /* !_POSIX_SOURCE */
#endif /* !__INSIDE_CYGWIN__ */
#ifdef __cplusplus
/* $NetBSD: grp.h,v 1.7 1995/04/29 05:30:40 cgd Exp $ */
/*-
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)grp.h 8.2 (Berkeley) 1/21/94
*/
#ifndef _GRP_H_
#define _GRP_H_
#include <sys/cdefs.h>
#include <sys/types.h>
#ifdef __CYGWIN__
#include <cygwin/grp.h>
#endif
#if !defined(_POSIX_SOURCE) && !defined(_XOPEN_SOURCE)
#define _PATH_GROUP "/etc/group"
#endif
struct group {
char *gr_name; /* group name */
char *gr_passwd; /* group password */
gid_t gr_gid; /* group id */
char **gr_mem; /* group members */
};
#ifdef __cplusplus
extern "C" {
#endif
#ifndef __INSIDE_CYGWIN__
struct group *getgrgid (gid_t);
struct group *getgrnam (const char *);
#if defined __POSIX_VISIBLE || defined __BSD_VISIBLE
int getgrnam_r (const char *, struct group *,
char *, size_t, struct group **);
int getgrgid_r (gid_t, struct group *,
char *, size_t, struct group **);
#endif
#if defined __BSD_VISIBLE || defined _XOPEN_SOURCE_EXTENDED
void setgrent (void);
#if __XSI_VISIBLE >= 700
struct group *getgrent (void);
void endgrent (void);
#endif
#endif
#if defined __BSD_VISIBLE
int initgroups (const char *, gid_t);
#endif
#ifndef __CYGWIN__
void setgrfile (const char *); /* 4.3BSD-Reno & Minix */
char *group_from_gid (gid_t, int);
int setgroupent (int); /* 4.3BSD-Reno & Mac OS X */
#endif /* !__CYGWIN__ */
#endif /* !__INSIDE_CYGWIN__ */
#ifdef __cplusplus
}
#endif
#endif /* !_GRP_H_ */
Torsten Bögershausen
