Ashmem functions compile when size_t != __u32

src/utils/android/ashmem.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * Implementation of the user-space ashmem API for devices, which have our
  * ashmem-enabled kernel. See ashmem-sim.c for the "fake" tmp-based version,
  * used by the simulator.
  */
 
 #include <android/ashmem.h>
 
 #include <unistd.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
 #include <fcntl.h>
 
 #include <linux/ashmem.h>
 
+#include <SkTypes.h>  // SkASSERT
+
 #define ASHMEM_DEVICE   "/dev/ashmem"
 
 /*
  * ashmem_create_region - creates a new ashmem region and returns the file
  * descriptor, or <0 on error
  *
  * `name' is an optional label to give the region (visible in /proc/pid/maps)
  * `size' is the size of the region, in page-aligned bytes
  */
 int ashmem_create_region(const char *name, size_t size)
@@ skipping 24 matching lines @@
     return ret;
 }
 
 int ashmem_set_prot_region(int fd, int prot)
 {
     return ioctl(fd, ASHMEM_SET_PROT_MASK, prot);
 }
 
 int ashmem_pin_region(int fd, size_t offset, size_t len)
 {
-    struct ashmem_pin pin = { offset, len };
+    // Skia only calls this when offset=len=0.
+    struct ashmem_pin pin = { static_cast<__u32>(offset),
+                              static_cast<__u32>(len) };
+    SkASSERT(pin.offset == offset && pin.len == len);
     return ioctl(fd, ASHMEM_PIN, &pin);
 }
 
 int ashmem_unpin_region(int fd, size_t offset, size_t len)
 {
-    struct ashmem_pin pin = { offset, len };
+    // Skia only calls this when offset=len=0.
+    struct ashmem_pin pin = { static_cast<__u32>(offset),
+                              static_cast<__u32>(len) };
+    SkASSERT(pin.offset == offset && pin.len == len);
     return ioctl(fd, ASHMEM_UNPIN, &pin);
 }
 
 int ashmem_get_size_region(int fd)
 {
   return ioctl(fd, ASHMEM_GET_SIZE, NULL);
 }
 
 int ashmem_purge_all_caches(int fd)
 {
   return ioctl(fd, ASHMEM_PURGE_ALL_CACHES, NULL);
 }