Marked libisofs SVN copy as outdated (use bzr on lp)

libisofs_outdated/attic/libisofs/file_src.h

@@ -0,0 +1,94 @@
+
+/*
+ * Class for reading data from files, with base implementations
+ * for reading local filesystem files and previous session files.
+ * 
+ * TODO this is kept private for now, it can be useful to make that
+ * public later.
+ */
+
+#ifndef FILE_SRC_H_
+#define FILE_SRC_H_
+
+#include <sys/types.h>
+
+struct data_source;
+
+struct iso_file_src {
+	
+	/**
+	 * Opens the file. 
+	 * This should be called before any call to read_block().
+	 * @return 1 on success, <= 0 on error
+	 */
+	int (*open)(struct iso_file_src *src);
+	
+	/**
+	 * Close the file.
+	 * This should be called when the iso_file_src is no more needed.
+	 */
+	void (*close)(struct iso_file_src *src);
+	
+	/** 
+	 * Read data from the file in 2048 bytes chunks.
+	 * 
+	 * A pointer to the contents of the file will be updated, in such a way
+	 * that each time this function is called, new data is read to the buffer.
+	 * It behaves in the same way as usual read(2) call this way.
+	 * 
+	 * This always reads 2048 bytes, unless an EOF is found, or we reach the
+	 * size previously returned by get_size(). In this case, the buffer is 
+	 * completed with 0s.
+	 * 
+	 * @param buffer Buffer where the data will be written. Its size must
+	 *               be at least 2048 bytes.
+	 * @return
+	 * 		1 if file contains more data. If we reach EOF before the expected
+	 *      size, this keeps returning 1, and next blocks are filled with 0s.
+	 * 	    0 when we reach the expected size, that in normal usage is also EOF
+	 *      on file.
+	 *      < 0 on error. If such case, next calls to read_block will keep
+	 *      returning < 0 until we reach the expected size, filling blocks with
+	 *      0s.
+	 */
+	int (*read_block)(struct iso_file_src *src, unsigned char *buffer);
+
+	/** 
+	 * Get the size in bytes of the file. 
+	 * 
+	 * This is set when the iso_file_src is created, and should not change. If
+	 * the actual file size changes, it will be truncated or padding with 0s
+	 * when the block is read
+	 */
+	off_t (*get_size)(struct iso_file_src *);
+
+	/** Clean up the source specific data */
+	void (*free_data)(struct iso_file_src *);
+
+	/** Source specific data */
+	void *data;
+	
+};
+
+/**
+ * Get a iso_file_src() for reading from a local filesystem file.
+ */
+struct iso_file_src* iso_file_src_from_path(const char *path);
+
+/**
+ * Get a iso_file_src() for reading from a previous image file.
+ * @param src data_source to read from previous image. It is not freed, 
+ *            so you need to free it when no more needed.
+ * @param block block on image where file begins
+ * @param nblocks number of block of the file
+ */
+struct iso_file_src* 
+iso_file_src_from_prev_img(struct data_source* src, int block, off_t size);
+
+/**
+ * free a iso_file_src
+ */
+void iso_file_src_free(struct iso_file_src *src);
+
+
+#endif /*FILE_SRC_H_*/