Add NaClDescIoDescMakeFromHandle

src/trusted/desc/nacl_desc_io.c

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl Service Runtime.  I/O Descriptor / Handle abstraction.  Memory
  * mapping using descriptors.
  */
@@ skipping 72 matching lines @@
     NaClLog(LOG_FATAL,
             ("NaClDescIoDescMake:"
              " NaClDescIoDescCtor(0x%08"NACL_PRIxPTR",0x%08"NACL_PRIxPTR
              ") failed\n"),
             (uintptr_t) ndp,
             (uintptr_t) nhdp);
   }
   return ndp;
 }
 
+struct NaClDesc *NaClDescIoDescMakeFromHandle(NaClHandle handle) {
+  int posix_d;
+  struct NaClHostDesc *nhdp;
+  struct NaClDescIoDesc *desc;
+
+#if NACL_WINDOWS
+  posix_d = _open_osfhandle((intptr_t) handle, _O_RDWR | _O_BINARY);
+  if (-1 == posix_d)
+    return NULL;
+#else
+  posix_d = handle;
+#endif
+  nhdp = NaClHostDescPosixMake(posix_d, NACL_ABI_O_RDWR);
+  if (NULL == nhdp)
+    return NULL;
+  desc = NaClDescIoDescMake(nhdp);
+  return &desc->base;
+}
+
 struct NaClDescIoDesc *NaClDescIoDescOpen(char  *path,
                                           int   mode,
                                           int   perms) {
   struct NaClHostDesc *nhdp;
 
   nhdp = malloc(sizeof *nhdp);
   if (NULL == nhdp) {
     NaClLog(LOG_FATAL, "NaClDescIoDescOpen: no memory for %s\n", path);
   }
   if (0 != NaClHostDescOpen(nhdp, path, mode, perms)) {
@@ skipping 242 matching lines @@
 cleanup:
   if (rv < 0) {
     free(nhdp);
     free(ndidp);
     if (NACL_INVALID_HANDLE != h) {
       (void) NaClClose(h);
     }
   }
   return rv;
 }