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This patch is needed to allow builds with newer versions of
the GNU libc (2.16+).
commit 66712c23388e93e5c518ebc8515140fa0c807348
Author: Eric Blake <eblake@redhat.com>
Date: Thu Mar 29 13:30:41 2012 -0600
stdio: don't assume gets any more
Gnulib intentionally does not have a gets module, and now that C11
and glibc have dropped it, we should be more proactive about warning
any user on a platform that still has a declaration of this dangerous
interface.
* m4/stdio_h.m4 (gl_STDIO_H, gl_STDIO_H_DEFAULTS): Drop gets
support.
* modules/stdio (Makefile.am): Likewise.
* lib/stdio-read.c (gets): Likewise.
* tests/test-stdio-c++.cc: Likewise.
* m4/warn-on-use.m4 (gl_WARN_ON_USE_PREPARE): Fix comment.
* lib/stdio.in.h (gets): Make warning occur in more places.
* doc/posix-functions/gets.texi (gets): Update documentation.
Reported by Christer Solskogen.
Signed-off-by: Eric Blake <eblake@redhat.com>
diff --git a/gl/stdio.in.h b/gl/stdio.in.h
index aa7b599..c377b6e 100644
--- a/gl/stdio.in.h
+++ b/gl/stdio.in.h
@@ -698,22 +698,11 @@ _GL_WARN_ON_USE (getline, "getline is unportable - "
# endif
#endif
-#if @GNULIB_GETS@
-# if @REPLACE_STDIO_READ_FUNCS@ && @GNULIB_STDIO_H_NONBLOCKING@
-# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-# undef gets
-# define gets rpl_gets
-# endif
-_GL_FUNCDECL_RPL (gets, char *, (char *s) _GL_ARG_NONNULL ((1)));
-_GL_CXXALIAS_RPL (gets, char *, (char *s));
-# else
-_GL_CXXALIAS_SYS (gets, char *, (char *s));
-# undef gets
-# endif
-_GL_CXXALIASWARN (gets);
/* It is very rare that the developer ever has full control of stdin,
- so any use of gets warrants an unconditional warning. Assume it is
- always declared, since it is required by C89. */
+ so any use of gets warrants an unconditional warning; besides, C11
+ removed it. */
+#undef gets
+#if HAVE_RAW_DECL_GETS
_GL_WARN_ON_USE (gets, "gets is a security hole - use fgets instead");
#endif
@@ -1053,9 +1042,9 @@ _GL_WARN_ON_USE (snprintf, "snprintf is unportable - "
# endif
#endif
-/* Some people would argue that sprintf should be handled like gets
- (for example, OpenBSD issues a link warning for both functions),
- since both can cause security holes due to buffer overruns.
+/* Some people would argue that all sprintf uses should be warned about
+ (for example, OpenBSD issues a link warning for it),
+ since it can cause security holes due to buffer overruns.
However, we believe that sprintf can be used safely, and is more
efficient than snprintf in those safe cases; and as proof of our
belief, we use sprintf in several gnulib modules. So this header
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