initial OS X support

Well, support may be too concrete of a term. There is a lot that is
missing in OS X, and not everything can be implemented with portability
shims. The time APIs in OS X seem to have frozen with NeXTSTEP and never
advanced with POSIX.

Makefile.am

@@ -94,6 +94,24 @@ libcompat_la_SOURCES += compat/imsg.c
 libcompat_la_SOURCES += compat/imsg-buffer.c
 endif
 
+if !HAVE_CLOCK_GETRES
+libcompat_la_SOURCES += compat/clock_getres.c
+endif
+
+if !HAVE_SETRESGID
+libcompat_la_SOURCES += compat/bsd-setresgid.c
+endif
+
+if !HAVE_SETRESUID
+libcompat_la_SOURCES += compat/bsd-setresuid.c
+endif
+
+if !HAVE_CLOCK_GETTIME
+if HOST_DARWIN
+libcompat_la_SOURCES += compat/mach-clock_gettime.c
+endif
+endif
+
 if !HAVE_ARC4RANDOM
 libcompat_la_SOURCES += compat/arc4random.c
 

bsd-adjfreq.c

@@ -30,6 +30,23 @@
 #include "ntp.h"
 #include "ntpd.h"
 
+#ifndef NTP_ADJTIME
+
+#include <errno.h>
+
+/*
+ * Some sad but very popular platforms do not appear to provide a mechanism to
+ * adjust the time frequency at all!
+ */
+int
+adjfreq(const int64_t *freq, int64_t *oldfreq)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+#else
+
 /*
  * adjfreq (old)freq = nanosec. per seconds shifted left 32 bits
  * timex.freq is ppm / left shifted by SHIFT_USEC (16 bits), defined in timex.h
@@ -69,3 +86,5 @@ adjfreq(const int64_t *freq, int64_t *oldfreq)
 
 	return 0;
 }
+
+#endif

compat/bsd-setresgid.c

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2004, 2005 Darren Tucker (dtucker at zip com au).
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <unistd.h>
+
+int
+setresgid(gid_t rgid, gid_t egid, gid_t sgid)
+{
+	/* this is the only configuration tested */
+	if (rgid != egid || egid != sgid)
+		return -1;
+
+	# if defined(HAVE_SETREGID) && !defined(BROKEN_SETREGID)
+	if (setregid(rgid, egid) == -1)
+		return -1;
+	# else
+	if (setegid(egid) == -1)
+		return -1;
+	if (setgid(rgid)) == -1)
+		return -1;
+	# endif
+
+	return 0;
+}

compat/bsd-setresuid.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2004, 2005 Darren Tucker (dtucker at zip com au).
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+int
+setresuid(uid_t ruid, uid_t euid, uid_t suid)
+{
+	uid_t ouid;
+	int ret = -1;
+
+	/* Allow only the tested configuration. */
+	if (ruid != euid || euid != suid) {
+		errno = ENOSYS;
+		return -1;
+	}
+	ouid = getuid();
+
+# if defined(HAVE_SETREUID) && !defined(BROKEN_SETREUID)
+	if ((ret = setreuid(euid, euid)) == -1)
+		return -1;
+# else
+#  ifndef SETEUID_BREAKS_SETUID
+	if (seteuid(euid) == -1)
+		return -1;
+#  endif
+	if ((ret = setuid(ruid)) == -1)
+		return -1;
+# endif
+
+	/*
+	 * When real, effective and saved uids are the same and we have
+	 * changed uids, sanity check that we cannot restore the old uid.
+	 */
+	if (ruid == euid && euid == suid && ouid != ruid &&
+	    setuid(ouid) != -1 && seteuid(ouid) != -1) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	/*
+	 * Finally, check that the real and effective uids are what we
+	 * expect.
+	 */
+	if (getuid() != ruid || geteuid() != euid) {
+		errno = EACCES;
+		return -1;
+	}
+
+	return ret;
+}

compat/clock_getres.c

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 1999-2004 Damien Miller <djm@mindrot.org>
+ * Copyright (c) 2004 Darren Tucker <dtucker at zip com au>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/time.h>
+
+#ifdef HAVE_ADJTIMEX
+#include <sys/timex.h>
+#endif
+
+int
+clock_getres(clockid_t clk_id, struct timespec *tp)
+{
+# ifdef HAVE_ADJTIMEX
+        struct timex tmx;
+# endif
+
+        if (clk_id != CLOCK_REALTIME)
+                return -1;      /* not implemented */
+
+        tp->tv_sec = 0;
+
+# ifdef HAVE_ADJTIMEX
+        tmx.modes = 0;
+        if (adjtimex(&tmx) == -1)
+                return -1;
+        else
+                tp->tv_nsec = tmx.precision * 1000;     /* usec -> nsec */
+# else
+        /* assume default 10ms tick */
+        tp->tv_nsec = 10000000;
+# endif
+        return 0;
+}

compat/mach-clock_gettime.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 1999-2004 Damien Miller <djm@mindrot.org>
+ * Copyright (c) 2014 Brent Cook <bcook@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <mach/mach_time.h>
+#include <sys/time.h>
+
+#include <stdint.h>
+#include <time.h>
+
+int
+clock_gettime(clockid_t clk_id, struct timespec *ts)
+{
+	static uint64_t timebase_factor = 0;
+	mach_timebase_info_data_t timebase_info;
+	uint64_t nsec;
+
+        if (clk_id != CLOCK_REALTIME)
+                return -1;      /* not implemented */
+
+	if (timebase_factor == 0) {
+		mach_timebase_info(&timebase_info);
+		timebase_factor = timebase_info.numer / timebase_info.denom;
+	}
+
+	nsec = mach_absolute_time() * timebase_factor;
+	ts->tv_sec  = nsec / 1000000000UL;
+	ts->tv_nsec = nsec % 1000000000UL;
+
+	return 0;
+}

configure.ac

@@ -12,6 +12,10 @@ CFLAGS="$CFLAGS -Wall -std=gnu99 -g"
 case $host_os in
 	*darwin*)
 		HOST_OS=darwin
+		AC_DEFINE(SETEUID_BREAKS_SETUID,[],[setuid after seteuid doesn't work])
+		AC_DEFINE(BROKEN_SETREUID,[], [Broken setreuid])
+		AC_DEFINE(BROKEN_SETREGID,[], [Broken setregid])
+		AC_DEFINE(YYSTYPE_IS_DECLARED,[], [Broken bison])
 		;;
 	*freebsd*)
 		HOST_OS=freebsd
@@ -41,6 +45,9 @@ AM_CONDITIONAL([HOST_SOLARIS], [test x$HOST_OS = xsolaris])
 AC_CHECK_FUNC([clock_gettime],,
 	[AC_SEARCH_LIBS([clock_gettime],[rt posix4])])
 
+AC_CHECK_FUNC([clock_getres],,
+	[AC_SEARCH_LIBS([clock_getres],[rt posix4])])
+
 AC_CHECK_FUNC([dl_iterate_phdr],,
 	[AC_SEARCH_LIBS([dl_iterate_phdr],[dl])])
 
@@ -74,9 +81,11 @@ CFLAGS="$CFLAGS $CLANG_CFLAGS"
 LDFLAGS="$LDFLAGS $CLANG_FLAGS"
 
 # check functions that are expected to be in libc
-AC_CHECK_FUNCS([adjfreq arc4random_uniform asprintf explicit_bzero])
+AC_CHECK_FUNCS([adjfreq ntp_adjtime adjtimex])
+AC_CHECK_FUNCS([arc4random_uniform asprintf explicit_bzero])
 AC_CHECK_FUNCS([getentropy memmem poll reallocarray])
 AC_CHECK_FUNCS([setproctitle setgroups])
+AC_CHECK_FUNCS([setregid setresgid setreuid setresuid])
 AC_CHECK_FUNCS([strlcat strlcpy strndup strnlen strtonum])
 
 # check auxiliary libraries that might contain other functions
@@ -92,21 +101,25 @@ AM_CONDITIONAL([HAVE_ADJFREQ], [test "x$ac_cv_func_adjfreq" = xyes])
 AM_CONDITIONAL([HAVE_ARC4RANDOM], [test "x$ac_cv_func_arc4random" = xyes])
 AM_CONDITIONAL([HAVE_ARC4RANDOM_UNIFORM], [test "x$ac_cv_func_arc4random_uniform" = xyes])
 AM_CONDITIONAL([HAVE_ASPRINTF], [test "x$ac_cv_func_asprintf" = xyes])
+AM_CONDITIONAL([HAVE_CLOCK_GETRES], [test "x$ac_cv_func_clock_getres" = xyes])
+AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "x$ac_cv_func_clock_gettime" = xyes])
 AM_CONDITIONAL([HAVE_EXPLICIT_BZERO], [test "x$ac_cv_func_explicit_bzero" = xyes])
 AM_CONDITIONAL([HAVE_GETENTROPY], [test "x$ac_cv_func_getentropy" = xyes])
+AM_CONDITIONAL([HAVE_IMSG], [test "x$ac_cv_func_ibuf_open" = xyes])
+AM_CONDITIONAL([HAVE_MD5], [test "x$ac_cv_func_MD5Init" = xyes])
 AM_CONDITIONAL([HAVE_MEMMEM], [test "x$ac_cv_func_memmem" = xyes])
 AM_CONDITIONAL([HAVE_POLL], [test "x$ac_cv_func_poll" = xyes])
 AM_CONDITIONAL([HAVE_REALLOCARRAY], [test "x$ac_cv_func_reallocarray" = xyes])
 AM_CONDITIONAL([HAVE_SETGROUPS], [test "x$ac_cv_func_setgroups" = xyes])
+AM_CONDITIONAL([HAVE_SETRESGID], [test "x$ac_cv_func_setresgid" = xyes])
+AM_CONDITIONAL([HAVE_SETRESUID], [test "x$ac_cv_func_setresuid" = xyes])
 AM_CONDITIONAL([HAVE_SETPROCTITLE], [test "x$ac_cv_func_setproctitle" = xyes])
+AM_CONDITIONAL([HAVE_SHA512], [test "x$ac_cv_func_SHA512Init" = xyes])
 AM_CONDITIONAL([HAVE_STRLCAT], [test "x$ac_cv_func_strlcat" = xyes])
 AM_CONDITIONAL([HAVE_STRLCPY], [test "x$ac_cv_func_strlcpy" = xyes])
 AM_CONDITIONAL([HAVE_STRNDUP], [test "x$ac_cv_func_strndup" = xyes])
 AM_CONDITIONAL([HAVE_STRNLEN], [test "x$ac_cv_func_strnlen" = xyes])
 AM_CONDITIONAL([HAVE_STRTONUM], [test "x$ac_cv_func_strtonum" = xyes])
-AM_CONDITIONAL([HAVE_MD5], [test "x$ac_cv_func_MD5Init" = xyes])
-AM_CONDITIONAL([HAVE_SHA512], [test "x$ac_cv_func_SHA512Init" = xyes])
-AM_CONDITIONAL([HAVE_IMSG], [test "x$ac_cv_func_ibuf_open" = xyes])
 
 # overrides for arc4random_buf implementations with known issues
 AM_CONDITIONAL([HAVE_ARC4RANDOM],

include/time.h

@@ -0,0 +1,25 @@
+/*
+ * Public domain
+ * time.h compatibility shim
+ */
+
+#include_next <time.h>
+
+#ifndef LIBCOMPAT_TIME_H
+#define LIBCOMPAT_TIME_H
+
+#ifndef CLOCK_REALTIME
+typedef int clockid_t;
+#define CLOCK_REALTIME  1
+#define CLOCK_MONOTONIC 2	
+#endif
+
+#ifndef HAVE_CLOCK_GETRES
+int clock_getres(clockid_t clk_id, struct timespec *res);
+#endif
+
+#ifndef HAVE_CLOCK_GETTIME
+int clock_gettime(clockid_t clk_id, struct timespec *ts);
+#endif
+
+#endif

include/unistd.h

@@ -18,4 +18,12 @@ int getentropy(void *buf, size_t buflen);
 int setgroups(int ngroups, const gid_t *gidset);
 #endif
 
+#ifndef HAVE_SETRESGID
+int setresgid(gid_t rgid, gid_t egid, gid_t sgid);
+#endif
+
+#ifndef HAVE_SETRESUID
+int setresuid(uid_t ruid, uid_t euid, uid_t suid);
+#endif
+
 #endif