Add support for prlimit and prlimit64 on Linux.

1 files changed, 92 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/prlimit.c b/sysdeps/unix/sysv/linux/prlimit.c
new file mode 100644
index 0000000..6d61e9a
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/prlimit.c
@@ -0,0 +1,92 @@
+/* Copyright (C) 2010 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <sys/resource.h>
+#include <sys/syscall.h>
+
+
+#ifdef __NR_prlimit64
+int
+prlimit (__pid_t pid, enum __rlimit_resource resource,
+	 __const struct rlimit *new_limit, struct rlimit *old_limit)
+{
+  struct rlimit64 new_rlimit64_mem;
+  struct rlimit64 *new_rlimit64 = NULL;
+  struct rlimit64 old_rlimit64_mem;
+  struct rlimit64 *old_rlimit64 = (old_rlimiit != NULL
+				   ? &old_rlimit64_mem : NULL);
+
+  if (new_rlimit != NULL)
+    {
+      if (new_rlimit->rlim_cur == RLIM_INFINITY)
+	new_rlimit64_mem.rlim_cur = RLIM64_INFINITY;
+      else
+	new_rlimit64_mem.rlim_cur = new_rlimit->rlim_cur;
+      if (new_rlimit->rlim_max == RLIM_INFINITY)
+	new_rlimit64_mem.rlim_max =  = RLIM64_INFINITY;
+      else
+	new_rlimit64_mem.rlim_max = new_rlimit->rlim_max;
+      new_rlimit64 = &new_rlimit64_mem;
+    }
+
+  int res = INLINE_SYSCALL (prlimit64, 4, pid, resource, new_rlimit64,
+			    old_rlimit64);
+
+  if (res == 0 && old_limit != NULL)
+    {
+      /* The prlimit64 syscall is ill-designed for 32-bit machines.
+	 We have to provide a 32-bit variant since otherwise the LFS
+	 system would not work.  But what shall we do if the syscall
+	 succeeds but the old values do not fit into a rlimit
+	 structure?  We cannot return an error because the operation
+	 itself worked.  Best is perhaps to return RLIM_INFINITY.  */
+      old_rlimit->rlim_cur = old_rlimit64_mem.rlim_cur;
+      if (old_rlimit->rlim_cur != old_rlimit64_mem.rlim_cur)
+	{
+	  if (new_limit == NULL)
+	    {
+	      __set_errno (EOVERFLOW);
+	      return -1;
+	    }
+	  old_rlimit->rlim_cur = RLIM_INFINITY;
+	}
+      old_rlimit->rlim_max = old_rlimit64_mem.rlim_max;
+      if (old_rlimit->rlim_max != old_rlimit64_mem.rlim_max)
+	{
+	  if (new_limit == NULL)
+	    {
+	      __set_errno (EOVERFLOW);
+	      return -1;
+	    }
+	  old_rlimit->rlim_max = RLIM_INFINITY;
+	}
+    }
+
+  return res;
+}
+#else
+int
+prlimit (__pid_t pid, enum __rlimit_resource resource,
+	 __const struct rlimit *new_limit, struct rlimit *old_limit)
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+stub_warning (prlimit)
+#endif