xref: /freebsd/contrib/xz/src/liblzma/api/lzma/bcj.h (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 /**
2  * \file        lzma/bcj.h
3  * \brief       Branch/Call/Jump conversion filters
4  */
5 
6 /*
7  * Author: Lasse Collin
8  *
9  * This file has been put into the public domain.
10  * You can do whatever you want with this file.
11  *
12  * See ../lzma.h for information about liblzma as a whole.
13  */
14 
15 #ifndef LZMA_H_INTERNAL
16 #	error Never include this file directly. Use <lzma.h> instead.
17 #endif
18 
19 
20 /* Filter IDs for lzma_filter.id */
21 
22 #define LZMA_FILTER_X86         LZMA_VLI_C(0x04)
23 	/**<
24 	 * Filter for x86 binaries
25 	 */
26 
27 #define LZMA_FILTER_POWERPC     LZMA_VLI_C(0x05)
28 	/**<
29 	 * Filter for Big endian PowerPC binaries
30 	 */
31 
32 #define LZMA_FILTER_IA64        LZMA_VLI_C(0x06)
33 	/**<
34 	 * Filter for IA-64 (Itanium) binaries.
35 	 */
36 
37 #define LZMA_FILTER_ARM         LZMA_VLI_C(0x07)
38 	/**<
39 	 * Filter for ARM binaries.
40 	 */
41 
42 #define LZMA_FILTER_ARMTHUMB    LZMA_VLI_C(0x08)
43 	/**<
44 	 * Filter for ARM-Thumb binaries.
45 	 */
46 
47 #define LZMA_FILTER_SPARC       LZMA_VLI_C(0x09)
48 	/**<
49 	 * Filter for SPARC binaries.
50 	 */
51 
52 
53 /**
54  * \brief       Options for BCJ filters
55  *
56  * The BCJ filters never change the size of the data. Specifying options
57  * for them is optional: if pointer to options is NULL, default value is
58  * used. You probably never need to specify options to BCJ filters, so just
59  * set the options pointer to NULL and be happy.
60  *
61  * If options with non-default values have been specified when encoding,
62  * the same options must also be specified when decoding.
63  *
64  * \note        At the moment, none of the BCJ filters support
65  *              LZMA_SYNC_FLUSH. If LZMA_SYNC_FLUSH is specified,
66  *              LZMA_OPTIONS_ERROR will be returned. If there is need,
67  *              partial support for LZMA_SYNC_FLUSH can be added in future.
68  *              Partial means that flushing would be possible only at
69  *              offsets that are multiple of 2, 4, or 16 depending on
70  *              the filter, except x86 which cannot be made to support
71  *              LZMA_SYNC_FLUSH predictably.
72  */
73 typedef struct {
74 	/**
75 	 * \brief       Start offset for conversions
76 	 *
77 	 * This setting is useful only when the same filter is used
78 	 * _separately_ for multiple sections of the same executable file,
79 	 * and the sections contain cross-section branch/call/jump
80 	 * instructions. In that case it is beneficial to set the start
81 	 * offset of the non-first sections so that the relative addresses
82 	 * of the cross-section branch/call/jump instructions will use the
83 	 * same absolute addresses as in the first section.
84 	 *
85 	 * When the pointer to options is NULL, the default value (zero)
86 	 * is used.
87 	 */
88 	uint32_t start_offset;
89 
90 } lzma_options_bcj;
91