~bzr-pqm/bzr/bzr.dev : contents of bzrlib/delta.h at revision 5767

~bzr-pqm/bzr/bzr.dev : (revision 5767)

0.17.31 by John Arbash Meinel Bring in the 'rabin' experiment.	1	/*
	2	* delta.h: headers for delta functionality
	3	*
	4	* Adapted from GIT for Bazaar by
	5	* John Arbash Meinel <john@arbash-meinel.com> (C) 2009
	6	*
	7	* This code is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	11	#ifndef DELTA_H
	12	#define DELTA_H
	13
	14	/* opaque object for delta index */
	15	struct delta_index;
	16
0.23.42 by John Arbash Meinel Change the code around again.	17	struct source_info {
0.23.57 by John Arbash Meinel Change the formatting, replace \t with spaces to be consistent with bzr coding.	18	const void buf; / Pointer to the beginning of source data */
	19	unsigned long size; /* Total length of source data */
	20	unsigned long agg_offset; /* Start of source data as part of the
	21	aggregate source */
0.23.42 by John Arbash Meinel Change the code around again.	22	};
0.23.42 by John Arbash Meinel Change the code around again.	23
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	24
	25	/* result type for functions that have multiple failure modes */
	26	typedef enum {
	27	DELTA_OK, /* Success */
	28	DELTA_OUT_OF_MEMORY, /* Could not allocate required memory */
	29	DELTA_INDEX_NEEDED, /* A delta_index must be passed */
	30	DELTA_SOURCE_EMPTY, /* A source_info had no content */
	31	DELTA_SOURCE_BAD, /* A source_info had invalid or corrupt content */
5698.2.6 by Martin Also adapt create_delta to the return code interface as it uses malloc	32	DELTA_BUFFER_EMPTY, /* A buffer pointer and size */
5698.2.7 by Martin Non-code fixes noticed looking at full diff	33	DELTA_SIZE_TOO_BIG, /* Delta data is larger than the max requested */
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	34	} delta_result;
	35
	36
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	37	/*
	38	* create_delta_index: compute index data from given buffer
	39	*
5698.2.8 by Martin Tweak function descriptions in delta header for clarity	40	* Returns a delta_result status, when DELTA_OK then *fresh is set to a struct
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	41	* delta_index that should be passed to subsequent create_delta() calls, or to
5698.2.8 by Martin Tweak function descriptions in delta header for clarity	42	* free_delta_index(). Other values are a failure, and *fresh is unset.
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	43	* The given buffer must not be freed nor altered before free_delta_index() is
	44	* called. The resultant struct must be freed using free_delta_index().
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	45	*/
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	46	extern delta_result
0.23.43 by John Arbash Meinel Change the internals to allow delta indexes to be expanded with new source data.	47	create_delta_index(const struct source_info *src,
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	48	struct delta_index *old,
	49	struct delta_index **fresh);
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	50
0.23.45 by John Arbash Meinel Add a function that updates the index for delta bytes.	51
	52	/*
	53	* create_delta_index_from_delta: compute index data from given buffer
	54	*
5698.2.8 by Martin Tweak function descriptions in delta header for clarity	55	* Returns a delta_result status, when DELTA_OK then *fresh is set to a struct
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	56	* delta_index that should be passed to subsequent create_delta() calls, or to
5698.2.8 by Martin Tweak function descriptions in delta header for clarity	57	* free_delta_index(). Other values are a failure, and *fresh is unset.
0.23.45 by John Arbash Meinel Add a function that updates the index for delta bytes.	58	* The bytes must be in the form of a delta structure, as generated by
	59	* create_delta(). The generated index will only index the insert bytes, and
	60	* not any of the control structures.
	61	*/
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	62	extern delta_result
0.23.45 by John Arbash Meinel Add a function that updates the index for delta bytes.	63	create_delta_index_from_delta(const struct source_info *delta,
5698.2.5 by Martin Switch approach to delta function interfaces and use a return code and outparam	64	struct delta_index *old,
	65	struct delta_index **fresh);
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	66	/*
	67	* free_delta_index: free the index created by create_delta_index()
	68	*
	69	* Given pointer must be what create_delta_index() returned, or NULL.
	70	*/
	71	extern void free_delta_index(struct delta_index *index);
	72
	73	/*
	74	* sizeof_delta_index: returns memory usage of delta index
	75	*
	76	* Given pointer must be what create_delta_index() returned, or NULL.
	77	*/
	78	extern unsigned long sizeof_delta_index(struct delta_index *index);
	79
	80	/*
	81	* create_delta: create a delta from given index for the given buffer
	82	*
	83	* This function may be called multiple times with different buffers using
	84	* the same delta_index pointer. If max_delta_size is non-zero and the
5698.2.6 by Martin Also adapt create_delta to the return code interface as it uses malloc	85	* resulting delta is to be larger than max_delta_size then DELTA_SIZE_TOO_BIG
5698.2.8 by Martin Tweak function descriptions in delta header for clarity	86	* is returned. Otherwise on success, DELTA_OK is returned and *delta_data is
	87	* set to a new buffer with the delta data and *delta_size is updated with its
	88	* size. That buffer must be freed by the caller.
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	89	*/
5698.2.6 by Martin Also adapt create_delta to the return code interface as it uses malloc	90	extern delta_result
0.23.44 by John Arbash Meinel Remove the multi-index handling now that we have index combining instead.	91	create_delta(const struct delta_index *index,
5698.2.6 by Martin Also adapt create_delta to the return code interface as it uses malloc	92	const void *buf, unsigned long bufsize,
	93	unsigned long *delta_size, unsigned long max_delta_size,
	94	void **delta_data);
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	95
3735.38.1 by John Arbash Meinel Change the delta byte stream to remove the 'source length' entry.	96	/* the smallest possible delta size is 3 bytes
	97	* Target size, Copy command, Copy length
	98	*/
	99	#define DELTA_SIZE_MIN 3
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	100
	101	/*
	102	* This must be called twice on the delta data buffer, first to get the
	103	* expected source buffer size, and again to get the target buffer size.
	104	*/
3735.36.7 by John Arbash Meinel Get rid of inline and const, to reduce warnings and errors.	105	static unsigned long
	106	get_delta_hdr_size(unsigned char *datap, const unsigned char top)
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	107	{
3735.36.7 by John Arbash Meinel Get rid of inline and const, to reduce warnings and errors.	108	unsigned char data = datap;
0.23.57 by John Arbash Meinel Change the formatting, replace \t with spaces to be consistent with bzr coding.	109	unsigned char cmd;
	110	unsigned long size = 0;
	111	int i = 0;
	112	do {
	113	cmd = *data++;
	114	size \|= (cmd & ~0x80) << i;
	115	i += 7;
	116	} while (cmd & 0x80 && data < top);
	117	*datap = data;
	118	return size;
0.23.5 by John Arbash Meinel Minor changes to get diff-delta.c and patch-delta.c to compile.	119	}
	120
	121	#endif