xo_encoder.h revision 302408 
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 */
24extern xo_realloc_func_t xo_realloc;
25extern xo_free_func_t xo_free;
26
27typedef 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
55typedef int (*xo_encoder_func_t)(XO_ENCODER_HANDLER_ARGS);
56
57typedef struct xo_encoder_init_args_s {
58    unsigned xei_version;	   /* Current version */
59    xo_encoder_func_t xei_handler; /* Encoding handler */
60} xo_encoder_init_args_t;
61
62#define XO_ENCODER_VERSION	1 /* Current version */
63
64#define XO_ENCODER_INIT_ARGS \
65    xo_encoder_init_args_t *arg __attribute__ ((__unused__))
66
67typedef int (*xo_encoder_init_func_t)(XO_ENCODER_INIT_ARGS);
68/*
69 * Each encoder library must define a function named xo_encoder_init
70 * that takes the arguments defined in XO_ENCODER_INIT_ARGS.  It
71 * should return zero for success.
72 */
73#define XO_ENCODER_INIT_NAME_TOKEN xo_encoder_library_init
74#define XO_STRINGIFY(_x) #_x
75#define XO_STRINGIFY2(_x) XO_STRINGIFY(_x)
76#define XO_ENCODER_INIT_NAME XO_STRINGIFY2(XO_ENCODER_INIT_NAME_TOKEN)
77extern int XO_ENCODER_INIT_NAME_TOKEN (XO_ENCODER_INIT_ARGS);
78
79void
80xo_encoder_register (const char *name, xo_encoder_func_t func);
81
82void
83xo_encoder_unregister (const char *name);
84
85void *
86xo_get_private (xo_handle_t *xop);
87
88void
89xo_encoder_path_add (const char *path);
90
91void
92xo_set_private (xo_handle_t *xop, void *opaque);
93
94xo_encoder_func_t
95xo_get_encoder (xo_handle_t *xop);
96
97void
98xo_set_encoder (xo_handle_t *xop, xo_encoder_func_t encoder);
99
100int
101xo_encoder_init (xo_handle_t *xop, const char *name);
102
103xo_handle_t *
104xo_encoder_create (const char *name, xo_xof_flags_t flags);
105
106int
107xo_encoder_handle (xo_handle_t *xop, xo_encoder_op_t op,
108		   const char *name, const char *value);
109
110void
111xo_encoders_clean (void);
112
113const char *
114xo_encoder_op_name (xo_encoder_op_t op);
115
116#endif /* XO_ENCODER_H */
117