Consolidate Linux setrlimit and getrlimit implementation

This patch consolidates all Linux setrlimit and getrlimit on the default
sysdeps/unix/sysv/linux/{set,get}rlimit{64}.c.  It contains two exceptions:

  1. mips32 and mips64n32 which requires a versioned symbol for GLIBC 2.19
     and higher due a broken RLIM64_INFINITY constant.
  2. sparc32 does not define a compat symbol for getrlimit64 for old 2GB
     limit. I am not sure if it is required, but a RLIM_INFINITY fix [1]
     change its definition without adding a compat symbol.  This patch does
     not aim to address this possible issue, it follow current symbol
     export.

The default implementation uses prlimit64 for 64 bit rlim_t ({set,get}rlimit64)
and if it fails with ENOSYS it fall back to {get,set}rlimit syscall.  This
code path is only used on kernel older than 2.6.36 (basically now only x86)
and I avoid to user __ASSUME_PRLIMTI64 to simplify the implementation.  Once
x86 moves to be on par with other architectures regarding minimum kernel
supported we can get rid of using old syscalls and default path.

A new type size define is added, __RLIM_T_MATCHES_RLIM64_T, where is set as
default for 64 bits ports.  This allows the default implementation to avoid
{get,set}rlimit building and alias {get,set}rlimit64 to {get,set}rlimit.

Checked on x86_64, i386, armhf, aarch64, and powerpc64le.  I also did a
sanity build plus check-abi on all other supported architectures.

[1] Commit 9c96ff23858b0759e12ad69e3c4599931c90bee8

	Adhemerval Zanella  <adhemerval.zanella@linaro.org>
	Yury Norov  <ynorov@caviumnetworks.com>

	* bits/typesizes.h (__RLIM_T_MATCHES_RLIM64_T): define.
	* sysdeps/unix/sysv/linux/alpha/bits/typesizes.h
	(__RLIM_T_MATCHES_RLIM64_T): Likewise.
	* sysdeps/unix/sysv/linux/generic/bits/typesizes.h
	(__RLIM_T_MATCHES_RLIM64_T): Likewise.
	* sysdeps/unix/sysv/linux/s390/bits/typesizes.h [__s390x__]
	(__RLIM_T_MATCHES_RLIM64_T): Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/typesizes.h
	[__arch64__ || __sparcv9] (__RLIM_T_MATCHES_RLIM64_T): Likewise.
	* sysdeps/unix/sysv/linux/x86/bits/typesizes.h [__86_64__]
	(__RLIM_T_MATCHES_RLIM64_T): Likewise.
	* sysdeps/unix/sysv/linux/arm/Makefile [$(subdir) = resource]
	(sysdep_routines): Remove oldgetrlimit64.
	* sysdeps/unix/sysv/linux/i386/Makefile [$(subdir) = resource]
	(sysdep_routines): Likewise.
	* sysdeps/unix/sysv/linux/m68k/Makefile [$(subdir) = resource]
	(sysdep_routines): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/Makefile
	[$(subdir) = resource] (sysdep_routines): Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/Makefile
	[$(subdir) = resource] (sysdep_routines): Likewise.
	* sysdeps/unix/sysv/linux/arm/getrlimit64.c: Remove file.
	* sysdeps/unix/sysv/linux/arm/oldgetrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/hppa/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/oldgetrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/m68k/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/m68k/oldgetrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/oldgetrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/oldgetrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/sh/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/setrlimit64.c: Likewise.
	* sysdeps/sysv/linux/generic/wordsize-32/syscalls.list: Remove
	setrlimit and getrlimit.
	* sysdeps/unix/sysv/linux/hppa/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/i386/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/getrlimit.c: New file.
	* sysdeps/unix/sysv/linux/sparc/getrlimit64.c: Likewise.
	* sysdeps/unix/sysv/linux/setrlimit.c: Likewise.
	* sysdeps/unix/sysv/linux/getrlimit64.c (__getrlimit64): Handle
	__RLIM_T_MATCHES_RLIM64_T and add alias if defined.
	(__old_getrlimit64): Add compatibility symbol.
	* sysdeps/unix/sysv/linux/setrlimit64.c (__setrlimit): Likewise.

1 files changed, 64 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/setrlimit.c b/sysdeps/unix/sysv/linux/setrlimit.c
new file mode 100644
index 0000000000..78a3c33738
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/setrlimit.c
@@ -0,0 +1,64 @@
+/* Linux setrlimit implementation (32 bits off_t).
+   Copyright (C) 2016 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 <errno.h>
+#include <sys/resource.h>
+#include <sys/types.h>
+#include <shlib-compat.h>
+
+#if !__RLIM_T_MATCHES_RLIM64_T
+
+/* The compatibility symbol is meant to match the old __NR_getrlimit syscall
+   (with broken RLIM_INFINITY definition).  It should be provided iff
+   __NR_getrlimit and __NR_ugetrlimit are both defined.  */
+# ifndef __NR_ugetrlimit
+#  undef SHLIB_COMPAT
+#  define SHLIB_COMPAT(a, b, c) 0
+# endif
+
+int
+__setrlimit (enum __rlimit_resource resource, const struct rlimit *rlim)
+{
+# ifdef __NR_prlimit64
+  struct rlimit64 rlim64;
+
+  if (rlim->rlim_cur == RLIM_INFINITY)
+    rlim64.rlim_cur = RLIM64_INFINITY;
+  else
+    rlim64.rlim_cur = rlim->rlim_cur;
+  if (rlim->rlim_max == RLIM_INFINITY)
+    rlim64.rlim_max = RLIM64_INFINITY;
+  else
+    rlim64.rlim_max = rlim->rlim_max;
+
+  int res = INLINE_SYSCALL_CALL (prlimit64, 0, resource, &rlim64, NULL);
+  if (res == 0 || errno != ENOSYS)
+    return res;
+# endif
+  return INLINE_SYSCALL_CALL (setrlimit, resource, rlim);
+}
+
+# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)
+strong_alias (__setrlimit, __setrlimit_1)
+compat_symbol (libc, __setrlimit, setrlimit, GLIBC_2_0);
+versioned_symbol (libc, __setrlimit_1, setrlimit, GLIBC_2_2);
+# else
+weak_alias (__setrlimit, setrlimit)
+# endif
+
+#endif /* __RLIM_T_MATCHES_RLIM64_T  */