linux: Use 32-bit time_t for rusage

The Linux kernel expects rusage to use a 32-bit time_t, even on archs
with a 64-bit time_t (like RV32). To address this let's convert
rusage to/from 32-bit and 64-bit to ensure the kernel always gets
a 32-bit time_t.

This means that all 32-bit architectures with a 64-bit time_t will be
able to use this generic implementation.

This code is based on similar code in alpha, but adjusted to pass the
32-bit time_t to the kernel.

We can't directly call __wait4 as it expects a struct rusage but we have
to pass in and use a struct rusage32. The same appies to __getrusage.

3 files changed, 165 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c
new file mode 100644
index 0000000000..da2a9286c8
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c
@@ -0,0 +1,39 @@
+/* getrusage -- get the rusage struct.  Linux/tv32 version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sysdep.h>
+#include <tv32-compat.h>
+
+int
+__getrusage (int who, struct rusage *usage)
+{
+#if __TIMESIZE == 64
+  struct __rusage32 usage32;
+  if (INLINE_SYSCALL_CALL (getrusage, who, &usage32) == -1)
+    return -1;
+
+  rusage32_to_rusage64 (&usage32, usage);
+  return 0;
+#else
+  return INLINE_SYSCALL_CALL (getrusage, who, usage);
+#endif
+}
+
+strong_alias (__getrusage, getrusage)
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h b/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h
index aa960a6632..4b1aca0b2f 100644
--- a/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h
@@ -24,6 +24,7 @@
 #include <bits/types.h>
 #include <bits/types/time_t.h>
 #include <bits/types/struct_timeval.h>
+#include <bits/types/struct_rusage.h>
 
 /* Structures containing 'struct timeval' with 32-bit time_t.  */
 struct itimerval32
@@ -32,4 +33,50 @@ struct itimerval32
   struct __timeval_long it_value;
 };
 
+struct __rusage32
+{
+  struct __timeval_long ru_utime;	/* user time used */
+  struct __timeval_long ru_stime;	/* system time used */
+  long ru_maxrss;		/* maximum resident set size */
+  long ru_ixrss;		/* integral shared memory size */
+  long ru_idrss;		/* integral unshared data size */
+  long ru_isrss;		/* integral unshared stack size */
+  long ru_minflt;		/* page reclaims */
+  long ru_majflt;		/* page faults */
+  long ru_nswap;		/* swaps */
+  long ru_inblock;		/* block input operations */
+  long ru_oublock;		/* block output operations */
+  long ru_msgsnd;		/* messages sent */
+  long ru_msgrcv;		/* messages received */
+  long ru_nsignals;		/* signals received */
+  long ru_nvcsw;		/* voluntary context switches */
+  long ru_nivcsw;		/* involuntary " */
+};
+
+static inline void
+rusage32_to_rusage64 (const struct __rusage32 *restrict r32,
+                      struct rusage *restrict r64)
+{
+  /* Make sure the entire output structure is cleared, including
+     padding and reserved fields.  */
+  memset (r64, 0, sizeof *r64);
+
+  r64->ru_utime    = valid_timeval_long_to_timeval64 (r32->ru_utime);
+  r64->ru_stime    = valid_timeval_long_to_timeval64 (r32->ru_stime);
+  r64->ru_maxrss   = r32->ru_maxrss;
+  r64->ru_ixrss    = r32->ru_ixrss;
+  r64->ru_idrss    = r32->ru_idrss;
+  r64->ru_isrss    = r32->ru_isrss;
+  r64->ru_minflt   = r32->ru_minflt;
+  r64->ru_majflt   = r32->ru_majflt;
+  r64->ru_nswap    = r32->ru_nswap;
+  r64->ru_inblock  = r32->ru_inblock;
+  r64->ru_oublock  = r32->ru_oublock;
+  r64->ru_msgsnd   = r32->ru_msgsnd;
+  r64->ru_msgrcv   = r32->ru_msgrcv;
+  r64->ru_nsignals = r32->ru_nsignals;
+  r64->ru_nvcsw    = r32->ru_nvcsw;
+  r64->ru_nivcsw   = r32->ru_nivcsw;
+}
+
 #endif /* tv32-compat.h */
diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c
new file mode 100644
index 0000000000..f1a98a07ad
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c
@@ -0,0 +1,79 @@
+/* wait4 -- wait for process to change state.  Linux/RV32/tv32 version.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/wait.h>
+#include <sys/resource.h>
+#include <sysdep-cancel.h>
+#include <tv32-compat.h>
+
+pid_t
+__wait4 (pid_t pid, int *stat_loc, int options, struct rusage *usage)
+{
+  struct __rusage32 usage32;
+  idtype_t idtype = P_PID;
+
+  if (pid < -1)
+    {
+      idtype = P_PGID;
+      pid *= -1;
+    }
+  else if (pid == -1)
+    idtype = P_ALL;
+  else if (pid == 0)
+    idtype = P_PGID;
+
+  options |= WEXITED;
+
+  siginfo_t infop;
+  if (SYSCALL_CANCEL (waitid, idtype, pid, &infop, options, &usage32) < 0)
+    return -1;
+
+  if (stat_loc)
+    {
+      switch (infop.si_code)
+        {
+        case CLD_EXITED:
+          *stat_loc = W_EXITCODE (infop.si_status, 0);
+          break;
+        case CLD_DUMPED:
+          *stat_loc = WCOREFLAG | infop.si_status;
+    break;
+        case CLD_KILLED:
+          *stat_loc = infop.si_status;
+          break;
+        case CLD_TRAPPED:
+        case CLD_STOPPED:
+          *stat_loc = W_STOPCODE (infop.si_status);
+          break;
+        case CLD_CONTINUED:
+          *stat_loc = __W_CONTINUED;
+          break;
+  default:
+    *stat_loc = 0;
+    break;
+        }
+    }
+
+  if (usage != NULL)
+    rusage32_to_rusage64 (&usage32, usage);
+
+  return infop.si_pid;
+}
+
+libc_hidden_def (__wait4);
+weak_alias (__wait4, wait4)