add time32 ABI compat shims, compat source tree

these files provide the symbols for the traditional 32-bit time_t ABI
on existing 32-bit archs by wrapping the real, internal versions of
the corresponding functions, which always work with 64-bit time_t.
they are written to be as agnostic as possible to the implementation
details of the real functions, so that they can be written once and
mostly forgotten, but they are aware of details of the old (and
sometimes new) ABI, which is okay since ABI is fixed and cannot
change.

a new compat tree is added, separate from src, which the Makefile does
not see or use now, but which archs will be able to add to the build
process. we could also consider moving other things that are compat
shims here, like functions which are purely for glibc-ABI-compat, with
the goal of making it optional or just cleaning up the main src tree
to make the distinction between actual implementation/API files and
ABI-compat shims clear.

1 files changed, 40 insertions, 0 deletions

diff --git a/compat/time32/wait3_time32.c b/compat/time32/wait3_time32.c
new file mode 100644
index 00000000..8fe128ed
--- /dev/null
+++ b/compat/time32/wait3_time32.c
@@ -0,0 +1,40 @@
+#define _BSD_SOURCE
+#include "time32.h"
+#include <string.h>
+#include <stddef.h>
+#include <sys/wait.h>
+
+struct compat_rusage {
+	struct timeval32 ru_utime;
+	struct timeval32 ru_stime;
+	long	ru_maxrss;
+	long	ru_ixrss;
+	long	ru_idrss;
+	long	ru_isrss;
+	long	ru_minflt;
+	long	ru_majflt;
+	long	ru_nswap;
+	long	ru_inblock;
+	long	ru_oublock;
+	long	ru_msgsnd;
+	long	ru_msgrcv;
+	long	ru_nsignals;
+	long	ru_nvcsw;
+	long	ru_nivcsw;
+};
+
+pid_t __wait3_time32(int *status, int options, struct compat_rusage *usage)
+{
+	struct rusage ru;
+	int r = wait3(status, options, usage ? &ru : 0);
+	if (!r && usage) {
+		usage->ru_utime.tv_sec = ru.ru_utime.tv_sec;
+		usage->ru_utime.tv_usec = ru.ru_utime.tv_usec;
+		usage->ru_stime.tv_sec = ru.ru_stime.tv_sec;
+		usage->ru_stime.tv_usec = ru.ru_stime.tv_usec;
+		memcpy(&usage->ru_maxrss, &ru.ru_maxrss,
+			sizeof(struct compat_rusage) -
+			offsetof(struct compat_rusage, ru_maxrss));
+	}
+	return r;
+}