--- IO-AIO/AIO.xs	2017/06/23 22:33:06	1.248
+++ IO-AIO/AIO.xs	2017/09/22 05:20:39	1.250
@@ -106,6 +106,13 @@
 
 /*****************************************************************************/
 
+#include "libeio/config.h"
+
+#if HAVE_RLIMITS
+  #include <sys/time.h>
+  #include <sys/resource.h>
+#endif
+
 typedef SV SV8; /* byte-sv, used for argument-checking */
 typedef int aio_rfd; /* read file desriptor */
 typedef int aio_wfd; /* write file descriptor */
@@ -121,7 +128,6 @@
 
 #define EIO_NO_WRAPPERS 1
 
-#include "libeio/config.h"
 #include "libeio/eio.h"
 
 static int req_invoke    (eio_req *req);
@@ -1102,7 +1108,7 @@
     const_eio (FALLOC_FL_PUNCH_HOLE)
     const_eio (FALLOC_FL_COLLAPSE_RANGE)
     const_eio (FALLOC_FL_ZERO_RANGE)
-    const_eio (FALLOC_FL_INSET_RANGE)
+    const_eio (FALLOC_FL_INSERT_RANGE)
     const_eio (FALLOC_FL_UNSHARE_RANGE)
 
     const_eio (RENAME_NOREPLACE)
@@ -2051,6 +2057,78 @@
           }
 }
 
+UV
+get_fdlimit ()
+	CODE:
+#if HAVE_RLIMITS
+        struct rlimit rl;
+        if (0 == getrlimit (RLIMIT_NOFILE, &rl))
+	  XSRETURN_UV (rl.rlim_cur == RLIM_INFINITY ? (UV)-1 : rl.rlim_cur);
+#endif
+        XSRETURN_UNDEF;
+	OUTPUT:
+        RETVAL
+
+void
+min_fdlimit (UV limit = 0x7fffffffU)
+	CODE:
+{
+#if HAVE_RLIMITS
+        struct rlimit rl;
+        rlim_t orig_rlim_max;
+        UV bit;
+
+        if (0 != getrlimit (RLIMIT_NOFILE, &rl))
+          goto fail;
+
+        if (rl.rlim_cur == RLIM_INFINITY)
+          XSRETURN_YES;
+
+        orig_rlim_max = rl.rlim_max == RLIM_INFINITY ? ((rlim_t)0)-1 : rl.rlim_max;
+
+        if (rl.rlim_cur < limit)
+          {
+            rl.rlim_cur = limit;
+
+            if (rl.rlim_max < rl.rlim_cur && rl.rlim_max != RLIM_INFINITY)
+              rl.rlim_max = rl.rlim_cur;
+          }
+
+        if (0 == setrlimit (RLIMIT_NOFILE, &rl))
+          XSRETURN_YES;
+
+        if (errno == EPERM)
+          {
+            /* setlimit failed with EPERM - maybe we can't raise the hardlimit, or maybe */
+            /* our limit overflows a system-wide limit */
+            /* try an adaptive algorithm, but do not lower the hardlimit */
+            rl.rlim_max = 0;
+            for (bit = 0x40000000U; bit; bit >>= 1)
+              {
+                rl.rlim_max |= bit;
+                rl.rlim_cur = rl.rlim_max;
+
+                /* nevr decrease the hard limit */
+                if (rl.rlim_max < orig_rlim_max)
+                  break;
+
+                if (0 != setrlimit (RLIMIT_NOFILE, &rl))
+                  rl.rlim_max &= ~bit; /* too high, remove bit again */
+              }
+
+            /* now, raise the soft limit to the max permitted */
+            if (0 == getrlimit (RLIMIT_NOFILE, &rl))
+              {
+                rl.rlim_cur = rl.rlim_max;
+                if (0 == setrlimit (RLIMIT_NOFILE, &rl))
+                  errno = EPERM;
+              }
+	  }
+#endif
+        fail:
+        XSRETURN_UNDEF;
+}
+
 void _on_next_submit (SV *cb)
 	CODE:
         SvREFCNT_dec (on_next_submit);