atlas-probe: Fix compilation with gcc11

This uses some definitions from <sys/cdefs.h> in gcc 8.4.0, not present
in musl or gcc11.

Also use clock_gettime() instead of syscall(__NR_clock_gettime,...),
which is not currently defined.

Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>

net/atlas-probe/patches/002-Avoid-problems-with-64-bit-time_t.patch

@@ -0,0 +1,74 @@
+From b83524b19ca6e5e58dded77fad37f17a177766ff Mon Sep 17 00:00:00 2001
+From: Eneas U de Queiroz <cotequeiroz@gmail.com>
+Date: Fri, 8 Oct 2021 14:39:52 -0300
+Subject: [PATCH 1/2] Avoid problems with 64-bit time_t
+
+The clock_gettime() calls are being handled by calling
+syscall(__NR_clock_gettime, ...), which is not portable between systems
+using 32-bit and 64-bit time_t.  This is being done to avoid having to
+link agains librt.
+
+So, use the standard function, and add a test to see if we can compile
+a test without the library, including it otherwise.
+
+Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
+
+--- a/Makefile.flags
++++ b/Makefile.flags
+@@ -124,6 +124,12 @@ CFLAGS += --sysroot=$(CONFIG_SYSROOT)
+ export SYSROOT=$(CONFIG_SYSROOT)
+ endif
+ 
++# glibc versions before 2.17 need to link with -rt to use clock_gettime
++RT_NEEDED := $(shell echo -e '#include <time.h>\nint main(void){struct timespec tp; return clock_gettime(CLOCK_MONOTONIC, &tp);}' >rttest.c; $(CC) $(CFLAGS) -o /dev/null rttest.c >/dev/null 2>&1 || echo "y"; rm rttest.c)
++ifeq ($(RT_NEEDED),y)
++LDLIBS += rt
++endif
++
+ # Android has no separate crypt library
+ # gcc-4.2.1 fails if we try to feed C source on stdin:
+ #  echo 'int main(void){return 0;}' | $(CC) $(CFLAGS) -lcrypt -o /dev/null -xc -
+--- a/coreutils/date.c
++++ b/coreutils/date.c
+@@ -37,7 +37,7 @@
+ //config:config FEATURE_DATE_NANO
+ //config:	bool "Support %[num]N nanosecond format specifier"
+ //config:	default n
+-//config:	depends on DATE  # syscall(__NR_clock_gettime)
++//config:	depends on DATE  # clock_gettime()
+ //config:	select PLATFORM_LINUX
+ //config:	help
+ //config:	  Support %[num]N format specifier. Adds ~250 bytes of code.
+@@ -265,9 +265,7 @@ int date_main(int argc UNUSED_PARAM, cha
+ #endif
+ 	} else {
+ #if ENABLE_FEATURE_DATE_NANO
+-		/* libc has incredibly messy way of doing this,
+-		 * typically requiring -lrt. We just skip all this mess */
+-		syscall(__NR_clock_gettime, CLOCK_REALTIME, &ts);
++		clock_gettime(CLOCK_REALTIME, &ts);
+ #else
+ 		time(&ts.tv_sec);
+ #endif
+--- a/libbb/time.c
++++ b/libbb/time.c
+@@ -243,7 +243,7 @@ char* FAST_FUNC strftime_YYYYMMDDHHMMSS(
+  * typically requiring -lrt. We just skip all this mess */
+ static void get_mono(struct timespec *ts)
+ {
+-	if (syscall(__NR_clock_gettime, CLOCK_MONOTONIC, ts))
++	if (clock_gettime(CLOCK_MONOTONIC, ts))
+ 		bb_error_msg_and_die("clock_gettime(MONOTONIC) failed");
+ }
+ unsigned long long FAST_FUNC monotonic_ns(void)
+--- a/runit/runsv.c
++++ b/runit/runsv.c
+@@ -55,7 +55,7 @@ ADVISED OF THE POSSIBILITY OF SUCH DAMAG
+  * typically requiring -lrt. We just skip all this mess */
+ static void gettimeofday_ns(struct timespec *ts)
+ {
+-	syscall(__NR_clock_gettime, CLOCK_REALTIME, ts);
++	clock_gettime(CLOCK_REALTIME, ts);
+ }
+ #else
+ static void gettimeofday_ns(struct timespec *ts)

net/atlas-probe/patches/003-Fix-compilation-with-gcc11.patch

@@ -0,0 +1,82 @@
+From b6b3cdc16eaa50b40623f1589ea51dd43ebb456d Mon Sep 17 00:00:00 2001
+From: Eneas U de Queiroz <cotequeiroz@gmail.com>
+Date: Fri, 8 Oct 2021 14:47:08 -0300
+Subject: [PATCH 2/2] Fix compilation with gcc11
+
+Currently, libbb.h counts on __THROW and __inline being defined.  They
+are internal macros used by glibc not meant to be publicly used.  This
+causes trouble, at least with a combination of gcc11 and musl, where
+nether have them defined.
+
+Use definitions from <sys/cdefs.h> in gcc 8.4.0 if they're missing.
+
+Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
+
+--- a/include/libbb.h
++++ b/include/libbb.h
+@@ -120,6 +120,65 @@
+ #ifdef DMALLOC
+ # include <dmalloc.h>
+ #endif
++
++/* Compatibility with musl & gcc 11. Taken from <sys/cdefs.h> in gcc 8.4.0 */
++#ifndef __THROW
++#ifdef __GNUC__
++
++/* All functions, except those with callbacks or those that
++   synchronize memory, are leaf functions.  */
++# if __GNUC_PREREQ (4, 6) && !defined _LIBC
++#  define __LEAF , __leaf__
++#  define __LEAF_ATTR __attribute__ ((__leaf__))
++# else
++#  define __LEAF
++#  define __LEAF_ATTR
++# endif
++
++/* GCC can always grok prototypes.  For C++ programs we add throw()
++   to help it optimize the function calls.  But this works only with
++   gcc 2.8.x and egcs.  For gcc 3.2 and up we even mark C functions
++   as non-throwing using a function attribute since programs can use
++   the -fexceptions options for C code as well.  */
++# if !defined __cplusplus && __GNUC_PREREQ (3, 3)
++#  define __THROW	__attribute__ ((__nothrow__ __LEAF))
++#  define __THROWNL	__attribute__ ((__nothrow__))
++#  define __NTH(fct)	__attribute__ ((__nothrow__ __LEAF)) fct
++# else
++#  if defined __cplusplus && __GNUC_PREREQ (2,8)
++#   define __THROW	throw ()
++#   define __THROWNL	throw ()
++#   define __NTH(fct)	__LEAF_ATTR fct throw ()
++#  else
++#   define __THROW
++#   define __THROWNL
++#   define __NTH(fct)	fct
++#  endif
++# endif
++
++#else	/* Not GCC.  */
++
++# define __inline		/* No inline functions.  */
++
++# define __THROW
++# define __THROWNL
++# define __NTH(fct)	fct
++
++#endif	/* GCC.  */
++#endif /* __THROW */
++
++#ifndef __nonnull
++/* The nonull function attribute allows to mark pointer parameters which
++   must not be NULL.  */
++#if __GNUC_PREREQ (3,3)
++# define __nonnull(params) __attribute__ ((__nonnull__ params))
++#else
++# define __nonnull(params)
++#endif
++#endif /* __nonnull */
++
++/* End of compatibility with musl & gcc 11. */
++
+ /* Just in case libc doesn't define some of these... */
+ #ifndef _PATH_PASSWD
+ #define _PATH_PASSWD  "/etc/passwd"

net/atlas-probe/patches/004-Comment-out-librt-testing.patch

@@ -0,0 +1,32 @@
+From df50c29210f18f959186bb974c33cefff2bcc15e Mon Sep 17 00:00:00 2001
+From: Eneas U de Queiroz <cotequeiroz@gmail.com>
+Date: Fri, 8 Oct 2021 22:34:37 -0300
+Subject: [PATCH] Comment out librt testing
+
+The packages feed Ci is apparently failing to execute the test:
+
+Makefile.flags:128: *** unterminated call to function 'shell':
+    missing ')'.  Stop.
+
+The call appears to be correct, but we already know that the library
+will not be needed for openwrt, so let's just leave it out.
+
+Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
+
+--- a/Makefile.flags
++++ b/Makefile.flags
+@@ -125,10 +125,10 @@ export SYSROOT=$(CONFIG_SYSROOT)
+ endif
+ 
+ # glibc versions before 2.17 need to link with -rt to use clock_gettime
+-RT_NEEDED := $(shell echo -e '#include <time.h>\nint main(void){struct timespec tp; return clock_gettime(CLOCK_MONOTONIC, &tp);}' >rttest.c; $(CC) $(CFLAGS) -o /dev/null rttest.c >/dev/null 2>&1 || echo "y"; rm rttest.c)
+-ifeq ($(RT_NEEDED),y)
+-LDLIBS += rt
+-endif
++#RT_NEEDED := $(shell echo -e '#include <time.h>\nint main(void){struct timespec tp; return clock_gettime(CLOCK_MONOTONIC, &tp);}' >rttest.c; $(CC) $(CFLAGS) -o /dev/null rttest.c >/dev/null 2>&1 || echo "y"; rm rttest.c)
++#ifeq ($(RT_NEEDED),y)
++#LDLIBS += rt
++#endif
+ 
+ # Android has no separate crypt library
+ # gcc-4.2.1 fails if we try to feed C source on stdin: