Move libcutils source to C++.

Just the minimial changes to get this to actually build, because otherwise
we always bog down trying to rewrite everything (when the real answer
is usually "stop using libcutils, it's awful").

This doesn't move a handful of files: two are basically just BSD libc
source, a couple have outstanding code reviews, and one can be deleted
(but I'll do that in a separate change).

I'm also skipping the presubmit hooks because otherwise clang-format
wants to reformat everything. I'll follow up with that...

Bug: N/A
Test: builds
Change-Id: I06403f465b67c8e493bad466dd76b1151eed5993

1 files changed, 93 insertions, 0 deletions

diff --git a/libcutils/ashmem-host.cpp b/libcutils/ashmem-host.cpp
new file mode 100644
index 000000000..d2c28f393
--- /dev/null
+++ b/libcutils/ashmem-host.cpp
@@ -0,0 +1,93 @@
+/*
+ * 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.
+ */
+
+#include <cutils/ashmem.h>
+
+/*
+ * Implementation of the user-space ashmem API for the simulator, which lacks
+ * an ashmem-enabled kernel. See ashmem-dev.c for the real ashmem-based version.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <utils/Compat.h>
+
+#ifndef __unused
+#define __unused __attribute__((__unused__))
+#endif
+
+int ashmem_create_region(const char *ignored __unused, size_t size)
+{
+    char pattern[PATH_MAX];
+    snprintf(pattern, sizeof(pattern), "/tmp/android-ashmem-%d-XXXXXXXXX", getpid());
+    int fd = mkstemp(pattern);
+    if (fd == -1) return -1;
+
+    unlink(pattern);
+
+    if (TEMP_FAILURE_RETRY(ftruncate(fd, size)) == -1) {
+      close(fd);
+      return -1;
+    }
+
+    return fd;
+}
+
+int ashmem_set_prot_region(int fd __unused, int prot __unused)
+{
+    return 0;
+}
+
+int ashmem_pin_region(int fd __unused, size_t offset __unused, size_t len __unused)
+{
+    return 0 /*ASHMEM_NOT_PURGED*/;
+}
+
+int ashmem_unpin_region(int fd __unused, size_t offset __unused, size_t len __unused)
+{
+    return 0 /*ASHMEM_IS_UNPINNED*/;
+}
+
+int ashmem_get_size_region(int fd)
+{
+    struct stat buf;
+    int result = fstat(fd, &buf);
+    if (result == -1) {
+        return -1;
+    }
+
+    /*
+     * Check if this is an "ashmem" region.
+     * TODO: This is very hacky, and can easily break.
+     * We need some reliable indicator.
+     */
+    if (!(buf.st_nlink == 0 && S_ISREG(buf.st_mode))) {
+        errno = ENOTTY;
+        return -1;
+    }
+
+    return buf.st_size;
+}