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+/*
+ * Copyright (C) 2012 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.
+ */
+
+#ifndef _LIBSPARSE_SPARSE_H_
+#define _LIBSPARSE_SPARSE_H_
+
+#include <stdbool.h>
+#include <stdint.h>
+
+struct sparse_file;
+
+/**
+ * sparse_file_new - create a new sparse file cookie
+ *
+ * @block_size - minimum size of a chunk
+ * @len - size of the expanded sparse file.
+ *
+ * Creates a new sparse_file cookie that can be used to associate data
+ * blocks. Can later be written to a file with a variety of options.
+ * block_size specifies the minimum size of a chunk in the file. The maximum
+ * size of the file is 2**32 * block_size (16TB for 4k block size).
+ *
+ * Returns the sparse file cookie, or NULL on error.
+ */
+struct sparse_file *sparse_file_new(unsigned int block_size, int64_t len);
+
+/**
+ * sparse_file_destroy - destroy a sparse file cookie
+ *
+ * @s - sparse file cookie
+ *
+ * Destroys a sparse file cookie. After destroy, all memory passed in to
+ * sparse_file_add_data can be freed by the caller
+ */
+void sparse_file_destroy(struct sparse_file *s);
+
+/**
+ * sparse_file_add_data - associate a data chunk with a sparse file
+ *
+ * @s - sparse file cookie
+ * @data - pointer to data block
+ * @len - length of the data block
+ * @block - offset in blocks into the sparse file to place the data chunk
+ *
+ * Associates a data chunk with a sparse file cookie. The region
+ * [block * block_size : block * block_size + len) must not already be used in
+ * the sparse file. If len is not a multiple of the block size the data
+ * will be padded with zeros.
+ *
+ * The data pointer must remain valid until the sparse file is closed or the
+ * data block is removed from the sparse file.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int sparse_file_add_data(struct sparse_file *s,
+ void *data, unsigned int len, unsigned int block);
+
+/**
+ * sparse_file_add_fill - associate a fill chunk with a sparse file
+ *
+ * @s - sparse file cookie
+ * @fill_val - 32 bit fill data
+ * @len - length of the fill block
+ * @block - offset in blocks into the sparse file to place the fill chunk
+ *
+ * Associates a chunk filled with fill_val with a sparse file cookie.
+ * The region [block * block_size : block * block_size + len) must not already
+ * be used in the sparse file. If len is not a multiple of the block size the
+ * data will be padded with zeros.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int sparse_file_add_fill(struct sparse_file *s,
+ uint32_t fill_val, unsigned int len, unsigned int block);
+
+/**
+ * sparse_file_add_file - associate a chunk of a file with a sparse file
+ *
+ * @s - sparse file cookie
+ * @filename - filename of the file to be copied
+ * @file_offset - offset into the copied file
+ * @len - length of the copied block
+ * @block - offset in blocks into the sparse file to place the file chunk
+ *
+ * Associates a chunk of an existing file with a sparse file cookie.
+ * The region [block * block_size : block * block_size + len) must not already
+ * be used in the sparse file. If len is not a multiple of the block size the
+ * data will be padded with zeros.
+ *
+ * Allows adding large amounts of data to a sparse file without needing to keep
+ * it all mapped. File size is limited by available virtual address space,
+ * exceptionally large files may need to be added in multiple chunks.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int sparse_file_add_file(struct sparse_file *s,
+ const char *filename, int64_t file_offset, unsigned int len,
+ unsigned int block);
+
+/**
+ * sparse_file_write - write a sparse file to a file
+ *
+ * @s - sparse file cookie
+ * @fd - file descriptor to write to
+ * @gz - write a gzipped file
+ * @sparse - write in the Android sparse file format
+ * @crc - append a crc chunk
+ *
+ * Writes a sparse file to a file. If gz is true, the data will be passed
+ * through zlib. If sparse is true, the file will be written in the Android
+ * sparse file format. If sparse is false, the file will be written by seeking
+ * over unused chunks, producing a smaller file if the filesystem supports
+ * sparse files. If crc is true, the crc of the expanded data will be
+ * calculated and appended in a crc chunk.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int sparse_file_write(struct sparse_file *s, int fd, bool gz, bool sparse,
+ bool crc);
+
+#endif