Try to use secure_getenv() in preference to __secure_getenv()

If secure_getenv() use it in preference to __secure_getenv().
Starting with (e)glibc version 2.17, secure_getenv() exists, while
__secure_getenv() only works with shared library links (where it is a
weak symbol), but not for static links with /lib/libc.a

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

configure

@@ -11010,7 +11010,7 @@ if test "$ac_res" != no; then :
 fi
 
 fi
-for ac_func in  	__secure_getenv 	backtrace 	blkid_probe_get_topology 	chflags 	fallocate 	fallocate64 	fchown 	fdatasync 	fstat64 	ftruncate64 	getdtablesize 	getmntinfo 	getpwuid_r 	getrlimit 	getrusage 	jrand48 	llseek 	lseek64 	mallinfo 	mbstowcs 	memalign 	mmap 	msync 	nanosleep 	open64 	pathconf 	posix_fadvise 	posix_memalign 	prctl 	setmntent 	setresgid 	setresuid 	srandom 	strcasecmp 	strdup 	strnlen 	strptime 	strtoull 	sync_file_range 	sysconf 	usleep 	utime 	valloc
+for ac_func in  	__secure_getenv 	backtrace 	blkid_probe_get_topology 	chflags 	fallocate 	fallocate64 	fchown 	fdatasync 	fstat64 	ftruncate64 	getdtablesize 	getmntinfo 	getpwuid_r 	getrlimit 	getrusage 	jrand48 	llseek 	lseek64 	mallinfo 	mbstowcs 	memalign 	mmap 	msync 	nanosleep 	open64 	pathconf 	posix_fadvise 	posix_memalign 	prctl 	secure_getenv 	setmntent 	setresgid 	setresuid 	srandom 	strcasecmp 	strdup 	strnlen 	strptime 	strtoull 	sync_file_range 	sysconf 	usleep 	utime 	valloc
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

configure.in

@@ -1025,6 +1025,7 @@ AC_CHECK_FUNCS(m4_flatten([
 	posix_fadvise
 	posix_memalign
 	prctl
+	secure_getenv
 	setmntent
 	setresgid
 	setresuid

lib/blkid/cache.c

@@ -11,6 +11,9 @@
  */
 
 #include "config.h"
+#if HAVE_SECURE_GETENV
+#define _GNU_SOURCE
+#endif
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -49,7 +52,9 @@ static char *safe_getenv(const char *arg)
 #endif
 #endif
 
-#ifdef HAVE___SECURE_GETENV
+#if defined(HAVE_SECURE_GETENV)
+	return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
 	return __secure_getenv(arg);
 #else
 	return getenv(arg);

lib/config.h.in

@@ -296,6 +296,9 @@
 /* Define to 1 if if struct sockaddr contains sa_len */
 #undef HAVE_SA_LEN
 
+/* Define to 1 if you have the `secure_getenv' function. */
+#undef HAVE_SECURE_GETENV
+
 /* Define to 1 if you have the <semaphore.h> header file. */
 #undef HAVE_SEMAPHORE_H
 

lib/et/error_message.c

@@ -17,6 +17,9 @@
  */
 
 #include "config.h"
+#if HAVE_SECURE_GETENV
+#define _GNU_SOURCE
+#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -209,7 +212,9 @@ static char *safe_getenv(const char *arg)
 #endif
 #endif
 
-#ifdef HAVE___SECURE_GETENV
+#if defined(HAVE_SECURE_GETENV)
+	return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
 	return __secure_getenv(arg);
 #else
 	return getenv(arg);

lib/ext2fs/test_io.c

@@ -10,6 +10,12 @@
  */
 
 #include "config.h"
+#if HAVE_SECURE_GETENV
+#define _GNU_SOURCE
+#endif
+#if HAVE_SECURE_GETENV
+#define _GNU_SOURCE
+#endif
 #include <stdio.h>
 #include <string.h>
 #if HAVE_UNISTD_H
@@ -173,7 +179,9 @@ static char *safe_getenv(const char *arg)
 #endif
 #endif
 
-#ifdef HAVE___SECURE_GETENV
+#if defined(HAVE_SECURE_GETENV)
+	return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
 	return __secure_getenv(arg);
 #else
 	return getenv(arg);

lib/ss/pager.c

@@ -15,6 +15,9 @@
  */
 
 #include "config.h"
+#if HAVE_SECURE_GETENV
+#define _GNU_SOURCE
+#endif
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -56,7 +59,9 @@ char *ss_safe_getenv(const char *arg)
 #endif
 #endif
 
-#ifdef HAVE___SECURE_GETENV
+#if defined(HAVE_SECURE_GETENV)
+	return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
 	return __secure_getenv(arg);
 #else
 	return getenv(arg);