xref: /freebsd/contrib/libxo/libxo/xo_encoder.h (revision 0957b409)
1 /*
2  * Copyright (c) 2015, Juniper Networks, Inc.
3  * All rights reserved.
4  * This SOFTWARE is licensed under the LICENSE provided in the
5  * ../Copyright file. By downloading, installing, copying, or otherwise
6  * using the SOFTWARE, you agree to be bound by the terms of that
7  * LICENSE.
8  * Phil Shafer, August 2015
9  */
10 
11 /*
12  * NOTE WELL: This file is needed to software that implements an
13  * external encoder for libxo that allows libxo data to be encoded in
14  * new and bizarre formats.  General libxo code should _never_
15  * include this header file.
16  */
17 
18 #ifndef XO_ENCODER_H
19 #define XO_ENCODER_H
20 
21 /*
22  * Expose libxo's memory allocation functions
23  */
24 extern xo_realloc_func_t xo_realloc;
25 extern xo_free_func_t xo_free;
26 
27 typedef unsigned xo_encoder_op_t;
28 
29 /* Encoder operations; names are in xo_encoder.c:xo_encoder_op_name() */
30 #define XO_OP_UNKNOWN		0
31 #define XO_OP_CREATE		1 /* Called when the handle is init'd */
32 #define XO_OP_OPEN_CONTAINER	2
33 #define XO_OP_CLOSE_CONTAINER	3
34 #define XO_OP_OPEN_LIST		4
35 #define XO_OP_CLOSE_LIST	5
36 #define XO_OP_OPEN_LEAF_LIST	6
37 #define XO_OP_CLOSE_LEAF_LIST	7
38 #define XO_OP_OPEN_INSTANCE	8
39 #define XO_OP_CLOSE_INSTANCE	9
40 #define XO_OP_STRING		10 /* Quoted UTF-8 string */
41 #define XO_OP_CONTENT		11 /* Other content */
42 #define XO_OP_FINISH		12 /* Finish any pending output */
43 #define XO_OP_FLUSH		13 /* Flush any buffered output */
44 #define XO_OP_DESTROY		14 /* Clean up function */
45 #define XO_OP_ATTRIBUTE		15 /* Attribute name/value */
46 #define XO_OP_VERSION		16 /* Version string */
47 
48 #define XO_ENCODER_HANDLER_ARGS					\
49 	xo_handle_t *xop __attribute__ ((__unused__)),		\
50 	xo_encoder_op_t op __attribute__ ((__unused__)),	\
51 	const char *name __attribute__ ((__unused__)),		\
52         const char *value __attribute__ ((__unused__)),		\
53 	void *private __attribute__ ((__unused__)),		\
54 	xo_xof_flags_t flags __attribute__ ((__unused__))
55 
56 typedef int (*xo_encoder_func_t)(XO_ENCODER_HANDLER_ARGS);
57 
58 typedef struct xo_encoder_init_args_s {
59     unsigned xei_version;	   /* Current version */
60     xo_encoder_func_t xei_handler; /* Encoding handler */
61 } xo_encoder_init_args_t;
62 
63 #define XO_ENCODER_VERSION	1 /* Current version */
64 
65 #define XO_ENCODER_INIT_ARGS \
66     xo_encoder_init_args_t *arg __attribute__ ((__unused__))
67 
68 typedef int (*xo_encoder_init_func_t)(XO_ENCODER_INIT_ARGS);
69 /*
70  * Each encoder library must define a function named xo_encoder_init
71  * that takes the arguments defined in XO_ENCODER_INIT_ARGS.  It
72  * should return zero for success.
73  */
74 #define XO_ENCODER_INIT_NAME_TOKEN xo_encoder_library_init
75 #define XO_STRINGIFY(_x) #_x
76 #define XO_STRINGIFY2(_x) XO_STRINGIFY(_x)
77 #define XO_ENCODER_INIT_NAME XO_STRINGIFY2(XO_ENCODER_INIT_NAME_TOKEN)
78 extern int XO_ENCODER_INIT_NAME_TOKEN (XO_ENCODER_INIT_ARGS);
79 
80 void
81 xo_encoder_register (const char *name, xo_encoder_func_t func);
82 
83 void
84 xo_encoder_unregister (const char *name);
85 
86 void *
87 xo_get_private (xo_handle_t *xop);
88 
89 void
90 xo_encoder_path_add (const char *path);
91 
92 void
93 xo_set_private (xo_handle_t *xop, void *opaque);
94 
95 xo_encoder_func_t
96 xo_get_encoder (xo_handle_t *xop);
97 
98 void
99 xo_set_encoder (xo_handle_t *xop, xo_encoder_func_t encoder);
100 
101 int
102 xo_encoder_init (xo_handle_t *xop, const char *name);
103 
104 xo_handle_t *
105 xo_encoder_create (const char *name, xo_xof_flags_t flags);
106 
107 int
108 xo_encoder_handle (xo_handle_t *xop, xo_encoder_op_t op,
109 		   const char *name, const char *value, xo_xof_flags_t flags);
110 
111 void
112 xo_encoders_clean (void);
113 
114 const char *
115 xo_encoder_op_name (xo_encoder_op_t op);
116 
117 #endif /* XO_ENCODER_H */
118