Make Skia for Android libjpeg use ashmem

platform_tools/android/third_party/ashmem/cutils/ashmem-dev.c

+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * 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 <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 "ashmem.h"
+
+#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)
+{
+        int fd, ret;
+
+        fd = open(ASHMEM_DEVICE, O_RDWR);
+        if (fd < 0)
+                return fd;
+
+        if (name) {
+                char buf[ASHMEM_NAME_LEN];
+
+                strlcpy(buf, name, sizeof(buf));
+                ret = ioctl(fd, ASHMEM_SET_NAME, buf);
+                if (ret < 0)
+                        goto error;
+        }
+
+        ret = ioctl(fd, ASHMEM_SET_SIZE, size);
+        if (ret < 0)
+                goto error;
+
+        return fd;
+
+error:
+        close(fd);
+        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 };
+        return ioctl(fd, ASHMEM_PIN, &pin);
+}
+
+int ashmem_unpin_region(int fd, size_t offset, size_t len)
+{
+        struct ashmem_pin pin = { offset, 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(void)
+{
+  const int fd = open(ASHMEM_DEVICE, O_RDWR);
+  if (fd < 0)
+    return fd;
+  const int ret = ioctl(fd, ASHMEM_PURGE_ALL_CACHES, 0);
+  close(fd);
+  return ret;
+}