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, 36 insertions, 12 deletions

diff --git a/sysdeps/unix/sysv/linux/setrlimit64.c b/sysdeps/unix/sysv/linux/setrlimit64.c
index 5f444d2ae7..8d2f7c6e53 100644
--- a/sysdeps/unix/sysv/linux/setrlimit64.c
+++ b/sysdeps/unix/sysv/linux/setrlimit64.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2010-2016 Free Software Foundation, Inc.
+/* Linux setrlimit64 implementation (64 bits off_t).
+   Copyright (C) 2010-2016 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
@@ -16,25 +17,37 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
-#include <sys/resource.h>
 #include <sys/types.h>
-#include <sysdep.h>
-#include <kernel-features.h>
+#include <shlib-compat.h>
+
+/* Add this redirection so the strong_alias for __RLIM_T_MATCHES_RLIM64_T
+   linking setlimit64 to {__}setrlimit does not throw a type error.  */
+#undef settrlimit
+#undef __sttrlimit
+#define setrlimit setrlimit_redirect
+#define __setrlimit __setrlimit_redirect
+#include <sys/resource.h>
+#undef setrlimit
+#undef __setrlimit
 
 /* Set the soft and hard limits for RESOURCE to *RLIMITS.
    Only the super-user can increase hard limits.
    Return 0 if successful, -1 if not (and sets errno).  */
 int
-setrlimit64 (enum __rlimit_resource resource, const struct rlimit64 *rlimits)
+__setrlimit64 (enum __rlimit_resource resource, const struct rlimit64 *rlimits)
 {
-#ifdef __ASSUME_PRLIMIT64
-  return INLINE_SYSCALL (prlimit64, 4, 0, resource, rlimits, NULL);
-#else
-# ifdef __NR_prlimit64
-  int res = INLINE_SYSCALL (prlimit64, 4, 0, resource, rlimits, NULL);
+  int res;
+
+#ifdef __NR_prlimit64
+  res = INLINE_SYSCALL_CALL (prlimit64, 0, resource, rlimits, NULL);
   if (res == 0 || errno != ENOSYS)
     return res;
-# endif
+#endif
+
+/* The fallback code only makes sense if the platform supports
+   __NR_setrlimit.  */
+#ifdef __NR_setrlimit
+# if !__RLIM_T_MATCHES_RLIM64_T
   struct rlimit rlimits32;
 
   if (rlimits->rlim_cur >= RLIM_INFINITY)
@@ -45,7 +58,18 @@ setrlimit64 (enum __rlimit_resource resource, const struct rlimit64 *rlimits)
     rlimits32.rlim_max = RLIM_INFINITY;
   else
     rlimits32.rlim_max = rlimits->rlim_max;
+# else
+#  define rlimits32 (*rlimits)
+# endif
 
-  return __setrlimit (resource, &rlimits32);
+  res = INLINE_SYSCALL_CALL (setrlimit, resource, &rlimits32);
 #endif
+
+  return res;
 }
+weak_alias (__setrlimit64, setrlimit64)
+
+#if __RLIM_T_MATCHES_RLIM64_T
+strong_alias (__setrlimit64, __setrlimit)
+weak_alias (__setrlimit64, setrlimit)
+#endif