upload android base code part6

android/system/extras/squashfs_utils/squashfs_utils.c

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2015 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 "squashfs_utils.h"
+
+#include <cutils/fs.h>
+#include <cutils/klog.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "squashfs_fs.h"
+
+#ifdef SQUASHFS_NO_KLOG
+#include <stdio.h>
+#define ERROR(x...)   fprintf(stderr, x)
+#else
+#define ERROR(x...)   KLOG_ERROR("squashfs_utils", x)
+#endif
+
+size_t squashfs_get_sb_size()
+{
+    return sizeof(struct squashfs_super_block);
+}
+
+int squashfs_parse_sb_buffer(const void *buf, struct squashfs_info *info)
+{
+    const struct squashfs_super_block *sb =
+        (const struct squashfs_super_block *)buf;
+
+    if (sb->s_magic != SQUASHFS_MAGIC) {
+        return -1;
+    }
+
+    info->block_size = sb->block_size;
+    info->inodes = sb->inodes;
+    info->bytes_used = sb->bytes_used;
+    // by default mksquashfs pads the filesystem to 4K blocks
+    info->bytes_used_4K_padded =
+        sb->bytes_used + (4096 - (sb->bytes_used & (4096 - 1)));
+
+    return 0;
+}
+
+int squashfs_parse_sb(const char *blk_device, struct squashfs_info *info)
+{
+    int ret = 0;
+    struct squashfs_super_block sb;
+    int data_device;
+
+    data_device = TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC));
+    if (data_device == -1) {
+        ERROR("Error opening block device (%s)\n", strerror(errno));
+        return -1;
+    }
+
+    if (TEMP_FAILURE_RETRY(read(data_device, &sb, sizeof(sb)))
+            != sizeof(sb)) {
+        ERROR("Error reading superblock\n");
+        ret = -1;
+        goto cleanup;
+    }
+
+    if (squashfs_parse_sb_buffer(&sb, info) == -1) {
+        ERROR("Not a valid squashfs filesystem\n");
+        ret = -1;
+        goto cleanup;
+    }
+
+cleanup:
+    close(data_device);
+    return ret;
+}