* MODULES.html.sh (func_all_modules):
* lib/unistd.in.h (getentropy, getrandom):
* m4/unistd_h.m4 (gl_UNISTD_H, gl_UNISTD_H_DEFAULTS):
* modules/unistd (unistd.h):
Add support for getentropy, getrandom.
* doc/glibc-functions/getentropy.texi (getentropy):
* doc/glibc-functions/getrandom.texi (getrandom):
These are now fixed on some platforms.
* lib/getentropy.c, lib/getrandom.c, lib/sys_random.in.h:
* m4/getentropy.m4, m4/getrandom.m4:
* modules/getentropy, modules/getentropy-tests:
* modules/getrandom, modules/getrandom-tests:
* tests/test-getentropy.c, tests/test-getrandom.c:
New files.
---
ChangeLog | 18 ++++++++++
MODULES.html.sh | 2 ++
doc/glibc-functions/getentropy.texi | 10 ++++--
doc/glibc-functions/getrandom.texi | 8 +++--
lib/getentropy.c | 51 ++++++++++++++++++++++++++++
lib/getrandom.c | 52 +++++++++++++++++++++++++++++
lib/sys_random.in.h | 9 +++++
lib/unistd.in.h | 34 +++++++++++++++++++
m4/getentropy.m4 | 16 +++++++++
m4/getrandom.m4 | 15 +++++++++
m4/unistd_h.m4 | 8 +++--
modules/getentropy | 29 ++++++++++++++++
modules/getentropy-tests | 12 +++++++
modules/getrandom | 44 ++++++++++++++++++++++++
modules/unistd | 4 +++
tests/test-getentropy.c | 43 ++++++++++++++++++++++++
16 files changed, 348 insertions(+), 7 deletions(-)
create mode 100644 lib/getentropy.c
create mode 100644 lib/getrandom.c
create mode 100644 lib/sys_random.in.h
create mode 100644 m4/getentropy.m4
create mode 100644 m4/getrandom.m4
create mode 100644 modules/getentropy
create mode 100644 modules/getentropy-tests
create mode 100644 modules/getrandom
create mode 100644 tests/test-getentropy.c
diff --git a/ChangeLog b/ChangeLog
index 6b2faf17e..b1acb99ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,21 @@
+2020-05-25 Paul Eggert <egg...@cs.ucla.edu>
+
+ getentropy, getrandom: new modules
+ * MODULES.html.sh (func_all_modules):
+ * lib/unistd.in.h (getentropy, getrandom):
+ * m4/unistd_h.m4 (gl_UNISTD_H, gl_UNISTD_H_DEFAULTS):
+ * modules/unistd (unistd.h):
+ Add support for getentropy, getrandom.
+ * doc/glibc-functions/getentropy.texi (getentropy):
+ * doc/glibc-functions/getrandom.texi (getrandom):
+ These are now fixed on some platforms.
+ * lib/getentropy.c, lib/getrandom.c, lib/sys_random.in.h:
+ * m4/getentropy.m4, m4/getrandom.m4:
+ * modules/getentropy, modules/getentropy-tests:
+ * modules/getrandom, modules/getrandom-tests:
+ * tests/test-getentropy.c, tests/test-getrandom.c:
+ New files.
+
2020-05-25 Bruno Haible <br...@clisp.org>
Add missing C99 dependencies.
diff --git a/MODULES.html.sh b/MODULES.html.sh
index 318a15a1d..4db2a77ec 100755
--- a/MODULES.html.sh
+++ b/MODULES.html.sh
@@ -3484,9 +3484,11 @@ func_all_modules ()
func_module forkpty
func_module getdomainname
func_module xgetdomainname
+ func_module getentropy
func_module getloadavg
func_module getpagesize
func_module getprogname
+ func_module getrandom
func_module getusershell
func_module lib-symbol-visibility
func_module login_tty
diff --git a/doc/glibc-functions/getentropy.texi
b/doc/glibc-functions/getentropy.texi
index 5ad873a71..5281dcd4e 100644
--- a/doc/glibc-functions/getentropy.texi
+++ b/doc/glibc-functions/getentropy.texi
@@ -15,15 +15,19 @@ Documentation:
@uref{https://www.kernel.org/doc/man-pages/online/pages/man3/getentropy.3.html,,man
getentropy}.
@end itemize
-Gnulib module: ---
+Gnulib module: getentropy
Portability problems fixed by Gnulib:
@itemize
+@item
+This function is missing on some platforms:
+glibc 2.24, Mac OS X 10.5, FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8,
+Solaris 11.0, Android 9.0.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@item
-This function is missing on many non-glibc platforms:
-glibc 2.24, Mac OS X 10.5, FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8,
AIX 7.1, HP-UX 11.31, IRIX 6.5, Solaris 11.0, Cygwin, mingw, MSVC 14, Android
9.0.
+This function is missing on some platforms:
+Minix 3.1.8, IRIX 6.5, mingw, MSVC 14.
@end itemize
diff --git a/doc/glibc-functions/getrandom.texi
b/doc/glibc-functions/getrandom.texi
index 25e899d63..2f4debcfe 100644
--- a/doc/glibc-functions/getrandom.texi
+++ b/doc/glibc-functions/getrandom.texi
@@ -19,11 +19,15 @@ Gnulib module: ---
Portability problems fixed by Gnulib:
@itemize
+@item
+This function is missing on some platforms:
+glibc 2.24, Mac OS X 10.5, FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8,
+Solaris 11.0, Android 9.0.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@item
-This function is missing on many non-glibc platforms:
-glibc 2.24, Mac OS X 10.5, FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8,
AIX 7.1, HP-UX 11.31, IRIX 6.5, Solaris 11.0, Cygwin, mingw, MSVC 14, Android
9.0.
+This function is missing on some platforms:
+Minix 3.1.8, IRIX 6.5, mingw, MSVC 14.
@end itemize
diff --git a/lib/getentropy.c b/lib/getentropy.c
new file mode 100644
index 000000000..2b6c3f55f
--- /dev/null
+++ b/lib/getentropy.c
@@ -0,0 +1,51 @@
+/* Fill a buffer with random bytes.
+ Copyright 2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+#include <config.h>
+
+#include <unistd.h>
+
+#include <errno.h>
+#include <sys/random.h>
+
+/* Overwrite BUFFER with random data. BUFFER contains LENGTH bytes.
+ LENGTH must be at most 256. Return 0 on success, -1 (setting
+ errno) on failure. */
+int
+getentropy (void *buffer, size_t length)
+{
+ char *buf = buffer;
+
+ if (length <= 256)
+ for (;;)
+ {
+ ssize_t bytes;
+ if (length == 0)
+ return 0;
+ while ((bytes = getrandom (buf, length, 0)) < 0)
+ if (errno != EINTR)
+ return -1;
+ if (bytes == 0)
+ break;
+ buf += bytes;
+ length -= bytes;
+ }
+
+ errno = EIO;
+ return -1;
+}
diff --git a/lib/getrandom.c b/lib/getrandom.c
new file mode 100644
index 000000000..9b6ecb43b
--- /dev/null
+++ b/lib/getrandom.c
@@ -0,0 +1,52 @@
+/* Obtain a series of random bytes.
+
+ Copyright 2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+#include <config.h>
+
+#include <sys/random.h>
+
+#include "minmax.h"
+#include <fcntl.h>
+#include <stdbool.h>
+#include <unistd.h>
+
+/* Set BUFFER (of size LENGTH) to random bytes under the control of FLAGS.
+ Return the number of bytes written, or -1 on error. */
+ssize_t
+getrandom (void *buffer, size_t length, unsigned int flags)
+{
+ static int randfd[2] = { -1, -1 };
+ bool devrandom = (flags & GRND_RANDOM) != 0;
+ int fd = randfd[devrandom];
+
+ if (fd < 0)
+ {
+ static char const randdevice[][MAX (sizeof NAME_OF_NONCE_DEVICE,
+ sizeof NAME_OF_RANDOM_DEVICE)]
+ = { NAME_OF_NONCE_DEVICE, NAME_OF_RANDOM_DEVICE };
+ int oflags = (O_RDONLY + O_CLOEXEC
+ + (flags & GRND_NONBLOCK ? O_NONBLOCK : 0));
+ fd = open (randdevice[devrandom], oflags);
+ if (fd < 0)
+ return fd;
+ randfd[devrandom] = fd;
+ }
+
+ return read (fd, buffer, length);
+}
diff --git a/lib/sys_random.in.h b/lib/sys_random.in.h
new file mode 100644
index 000000000..e3f308ce4
--- /dev/null
+++ b/lib/sys_random.in.h
@@ -0,0 +1,9 @@
+#ifndef _SYS_RANDOM_H
+#define _SYS_RANDOM_H 1
+
+#include <sys/types.h>
+#define GRND_NONBLOCK 1
+#define GRND_RANDOM 2
+ssize_t getrandom (void *, size_t, unsigned int);
+
+#endif
diff --git a/lib/unistd.in.h b/lib/unistd.in.h
index 1454d7e85..4a0d6655a 100644
--- a/lib/unistd.in.h
+++ b/lib/unistd.in.h
@@ -763,6 +763,22 @@ _GL_WARN_ON_USE (getdtablesize, "getdtablesize is
unportable - "
#endif
+#if @GNULIB_GETENTROPY@
+/* Fill a buffer with random bytes. */
+# if !@HAVE_GETENTROPY@
+_GL_FUNCDECL_SYS (getentropy, int, (void *buffer, size_t length));
+# endif
+_GL_CXXALIAS_SYS (getentropy, int, (void *buffer, size_t length));
+_GL_CXXALIASWARN (getentropy);
+#elif defined GNULIB_POSIXCHECK
+# undef getentropy
+# if HAVE_RAW_DECL_GETENTROPY
+_GL_WARN_ON_USE (getentropy, "getentropy is unportable - "
+ "use gnulib module getentropy for portability");
+# endif
+#endif
+
+
#if @GNULIB_GETGROUPS@
/* Return the supplemental groups that the current process belongs to.
It is unspecified whether the effective group id is in the list.
@@ -1014,6 +1030,24 @@ _GL_WARN_ON_USE (getpass, "getpass is unportable - "
#endif
+#if @GNULIB_GETRANDOM@
+/* Fill a buffer with random bytes. */
+# if !@HAVE_GETRANDOM@
+_GL_FUNCDECL_SYS (getrandom, int, (void *buffer, size_t length,
+ unsigned int flags));
+# endif
+_GL_CXXALIAS_SYS (getrandom, int, (void *buffer, size_t length,
+ unsigned int flags));
+_GL_CXXALIASWARN (getrandom);
+#elif defined GNULIB_POSIXCHECK
+# undef getrandom
+# if HAVE_RAW_DECL_GETRANDOM
+_GL_WARN_ON_USE (getrandom, "getrandom is unportable - "
+ "use gnulib module getrandom for portability");
+# endif
+#endif
+
+
#if @GNULIB_GETUSERSHELL@
/* Return the next valid login shell on the system, or NULL when the end of
the list has been reached. */
diff --git a/m4/getentropy.m4 b/m4/getentropy.m4
new file mode 100644
index 000000000..596544b2e
--- /dev/null
+++ b/m4/getentropy.m4
@@ -0,0 +1,16 @@
+# getentropy.m4
+dnl Copyright 2020 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by Paul Eggert.
+
+AC_DEFUN([gl_FUNC_GETENTROPY],
+[
+ AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+ AC_CHECK_FUNCS_ONCE([getentropy])
+ if test $ac_cv_func_getentropy = no; then
+ HAVE_GETENTROPY=0
+ fi
+])
diff --git a/m4/getrandom.m4 b/m4/getrandom.m4
new file mode 100644
index 000000000..ecb44aebf
--- /dev/null
+++ b/m4/getrandom.m4
@@ -0,0 +1,15 @@
+# getrandom.m4
+dnl Copyright 2020 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by Paul Eggert.
+
+AC_DEFUN([gl_FUNC_GETRANDOM],
+[
+ AC_CHECK_FUNCS_ONCE([getrandom])
+ if test "$ac_cv_func_getrandom" != yes; then
+ HAVE_GETRANDOM=0
+ fi
+])
diff --git a/m4/unistd_h.m4 b/m4/unistd_h.m4
index e776f3bd4..1f39d53e1 100644
--- a/m4/unistd_h.m4
+++ b/m4/unistd_h.m4
@@ -43,8 +43,8 @@ AC_DEFUN([gl_UNISTD_H],
#endif
]], [access chdir chown dup dup2 dup3 environ euidaccess faccessat fchdir
fchownat fdatasync fsync ftruncate getcwd getdomainname getdtablesize
- getgroups gethostname getlogin getlogin_r getpagesize getpass
- getusershell setusershell endusershell
+ getentropy getgroups gethostname getlogin getlogin_r getpagesize getpass
+ getrandom getusershell setusershell endusershell
group_member isatty lchown link linkat lseek pipe pipe2 pread pwrite
readlink readlinkat rmdir sethostname sleep symlink symlinkat
truncate ttyname_r unlink unlinkat usleep])
@@ -82,6 +82,7 @@ AC_DEFUN([gl_UNISTD_H_DEFAULTS],
GNULIB_GETCWD=0; AC_SUBST([GNULIB_GETCWD])
GNULIB_GETDOMAINNAME=0; AC_SUBST([GNULIB_GETDOMAINNAME])
GNULIB_GETDTABLESIZE=0; AC_SUBST([GNULIB_GETDTABLESIZE])
+ GNULIB_GETENTROPY=0; AC_SUBST([GNULIB_GETENTROPY])
GNULIB_GETGROUPS=0; AC_SUBST([GNULIB_GETGROUPS])
GNULIB_GETHOSTNAME=0; AC_SUBST([GNULIB_GETHOSTNAME])
GNULIB_GETLOGIN=0; AC_SUBST([GNULIB_GETLOGIN])
@@ -89,6 +90,7 @@ AC_DEFUN([gl_UNISTD_H_DEFAULTS],
GNULIB_GETOPT_POSIX=0; AC_SUBST([GNULIB_GETOPT_POSIX])
GNULIB_GETPAGESIZE=0; AC_SUBST([GNULIB_GETPAGESIZE])
GNULIB_GETPASS=0; AC_SUBST([GNULIB_GETPASS])
+ GNULIB_GETRANDOM=0; AC_SUBST([GNULIB_GETRANDOM])
GNULIB_GETUSERSHELL=0; AC_SUBST([GNULIB_GETUSERSHELL])
GNULIB_GROUP_MEMBER=0; AC_SUBST([GNULIB_GROUP_MEMBER])
GNULIB_ISATTY=0; AC_SUBST([GNULIB_ISATTY])
@@ -129,11 +131,13 @@ AC_DEFUN([gl_UNISTD_H_DEFAULTS],
HAVE_FSYNC=1; AC_SUBST([HAVE_FSYNC])
HAVE_FTRUNCATE=1; AC_SUBST([HAVE_FTRUNCATE])
HAVE_GETDTABLESIZE=1; AC_SUBST([HAVE_GETDTABLESIZE])
+ HAVE_GETENTROPY=1; AC_SUBST([HAVE_GETENTROPY])
HAVE_GETGROUPS=1; AC_SUBST([HAVE_GETGROUPS])
HAVE_GETHOSTNAME=1; AC_SUBST([HAVE_GETHOSTNAME])
HAVE_GETLOGIN=1; AC_SUBST([HAVE_GETLOGIN])
HAVE_GETPAGESIZE=1; AC_SUBST([HAVE_GETPAGESIZE])
HAVE_GETPASS=1; AC_SUBST([HAVE_GETPASS])
+ HAVE_GETRANDOM=1; AC_SUBST([HAVE_GETRANDOM])
HAVE_GROUP_MEMBER=1; AC_SUBST([HAVE_GROUP_MEMBER])
HAVE_LCHOWN=1; AC_SUBST([HAVE_LCHOWN])
HAVE_LINK=1; AC_SUBST([HAVE_LINK])
diff --git a/modules/getentropy b/modules/getentropy
new file mode 100644
index 000000000..9696c1e1d
--- /dev/null
+++ b/modules/getentropy
@@ -0,0 +1,29 @@
+Description:
+Fill buffer with random bytes.
+
+Files:
+lib/getentropy.c
+m4/getentropy.m4
+
+Depends-on:
+getrandom [test $HAVE_GETENTROPY = 0]
+extensions
+unistd
+
+configure.ac:
+gl_FUNC_GETENTROPY
+if test $HAVE_GETENTROPY = 0; then
+ AC_LIBOBJ([getentropy])
+fi
+gl_UNISTD_MODULE_INDICATOR([getentropy])
+
+Makefile.am:
+
+Include:
+<unistd.h>
+
+License:
+LGPL
+
+Maintainer:
+all
diff --git a/modules/getentropy-tests b/modules/getentropy-tests
new file mode 100644
index 000000000..b5c4b1144
--- /dev/null
+++ b/modules/getentropy-tests
@@ -0,0 +1,12 @@
+Files:
+tests/test-getentropy.c
+tests/signature.h
+tests/macros.h
+
+Depends-on:
+
+configure.ac:
+
+Makefile.am:
+TESTS += test-getentropy
+check_PROGRAMS += test-getentropy
diff --git a/modules/getrandom b/modules/getrandom
new file mode 100644
index 000000000..2ae374f61
--- /dev/null
+++ b/modules/getrandom
@@ -0,0 +1,44 @@
+Description:
+Fill buffer with random bytes.
+
+Files:
+lib/getrandom.c
+lib/sys_random.in.h
+m4/getrandom.m4
+
+Depends-on:
+crypto/gc-random [test $HAVE_GETRANDOM = 0]
+fcntl-h [test $HAVE_GETRANDOM = 0]
+minmax [test $HAVE_GETRANDOM = 0]
+open [test $HAVE_GETRANDOM = 0]
+
+configure.ac:
+gl_FUNC_GETRANDOM
+if test $HAVE_GETRANDOM = 0; then
+ AC_LIBOBJ([getrandom])
+fi
+gl_UNISTD_MODULE_INDICATOR([getrandom])
+
+Makefile.am:
+BUILT_SOURCES += sys/random.h
+
+# We need the following in order to create <sys/random.h> when the system
+# doesn't have one that works with the given compiler.
+sys/random.h: sys_random.in.h $(top_builddir)/config.status $(CXXDEFS_H)
$(WARN_ON_USE_H) $(ARG_NONNULL_H)
+ $(AM_V_at)$(MKDIR_P) sys
+ $(AM_V_GEN)rm -f $@-t $@ && \
+ { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
+ cat $(srcdir)/sys_random.in.h; \
+ } > $@-t && \
+ mv -f $@-t $@
+MOSTLYCLEANFILES += sys/random.h sys/random.h-t
+MOSTLYCLEANDIRS += sys
+
+Include:
+<sys/random.h>
+
+License:
+LGPL
+
+Maintainer:
+all
diff --git a/modules/unistd b/modules/unistd
index 3c28f36ca..dc32ce056 100644
--- a/modules/unistd
+++ b/modules/unistd
@@ -55,6 +55,7 @@ unistd.h: unistd.in.h $(top_builddir)/config.status
$(CXXDEFS_H) $(ARG_NONNULL_H
-e 's/@''GNULIB_GETCWD''@/$(GNULIB_GETCWD)/g' \
-e 's/@''GNULIB_GETDOMAINNAME''@/$(GNULIB_GETDOMAINNAME)/g' \
-e 's/@''GNULIB_GETDTABLESIZE''@/$(GNULIB_GETDTABLESIZE)/g' \
+ -e 's/@''GNULIB_GETENTROPY''@/$(GNULIB_GETENTROPY)/g' \
-e 's/@''GNULIB_GETGROUPS''@/$(GNULIB_GETGROUPS)/g' \
-e 's/@''GNULIB_GETHOSTNAME''@/$(GNULIB_GETHOSTNAME)/g' \
-e 's/@''GNULIB_GETLOGIN''@/$(GNULIB_GETLOGIN)/g' \
@@ -62,6 +63,7 @@ unistd.h: unistd.in.h $(top_builddir)/config.status
$(CXXDEFS_H) $(ARG_NONNULL_H
-e 's/@''GNULIB_GETOPT_POSIX''@/$(GNULIB_GETOPT_POSIX)/g' \
-e 's/@''GNULIB_GETPAGESIZE''@/$(GNULIB_GETPAGESIZE)/g' \
-e 's/@''GNULIB_GETPASS''@/$(GNULIB_GETPASS)/g' \
+ -e 's/@''GNULIB_GETRANDOM''@/$(GNULIB_GETRANDOM)/g' \
-e 's/@''GNULIB_GETUSERSHELL''@/$(GNULIB_GETUSERSHELL)/g' \
-e 's/@''GNULIB_GROUP_MEMBER''@/$(GNULIB_GROUP_MEMBER)/g' \
-e 's/@''GNULIB_ISATTY''@/$(GNULIB_ISATTY)/g' \
@@ -103,10 +105,12 @@ unistd.h: unistd.in.h $(top_builddir)/config.status
$(CXXDEFS_H) $(ARG_NONNULL_H
-e 's|@''HAVE_FSYNC''@|$(HAVE_FSYNC)|g' \
-e 's|@''HAVE_FTRUNCATE''@|$(HAVE_FTRUNCATE)|g' \
-e 's|@''HAVE_GETDTABLESIZE''@|$(HAVE_GETDTABLESIZE)|g' \
+ -e 's|@''HAVE_GETENTROPY''@|$(HAVE_GETENTROPY)|g' \
-e 's|@''HAVE_GETGROUPS''@|$(HAVE_GETGROUPS)|g' \
-e 's|@''HAVE_GETHOSTNAME''@|$(HAVE_GETHOSTNAME)|g' \
-e 's|@''HAVE_GETPAGESIZE''@|$(HAVE_GETPAGESIZE)|g' \
-e 's|@''HAVE_GETPASS''@|$(HAVE_GETPASS)|g' \
+ -e 's|@''HAVE_GETRANDOM''@|$(HAVE_GETRANDOM)|g' \
-e 's|@''HAVE_GROUP_MEMBER''@|$(HAVE_GROUP_MEMBER)|g' \
-e 's|@''HAVE_LCHOWN''@|$(HAVE_LCHOWN)|g' \
-e 's|@''HAVE_LINK''@|$(HAVE_LINK)|g' \
diff --git a/tests/test-getentropy.c b/tests/test-getentropy.c
new file mode 100644
index 000000000..845c5dcaf
--- /dev/null
+++ b/tests/test-getentropy.c
@@ -0,0 +1,43 @@
+/* Test the getentropy function.
+ Copyright 2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Paul Eggert. */
+
+#include <config.h>
+
+#include <unistd.h>
+
+#include <string.h>
+
+#include "signature.h"
+SIGNATURE_CHECK (getentropy, int, (void *, size_t));
+
+#include "macros.h"
+
+char empty_buf[256];
+char buf[256];
+
+int
+main (int argc, char *argv[])
+{
+ /* If this test fails, there's something wrong with the setup anyway. */
+ ASSERT (getentropy (buf, sizeof buf) == 0);
+
+ /* This test fails with probability 2**-2048. (Run it again if so. :-) */
+ ASSERT (memcmp (buf, empty_buf, sizeof buf) != 0);
+
+ return 0;
+}
--
2.17.1
