1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
/* Copyright (C) 2015-2017 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/** @file
* Module API definition and functions for (un)loading modules.
*/
#pragma once
#include "lib/defines.h"
#include "lib/utils.h"
#include "lib/layer.h"
struct kr_module;
struct kr_prop;
/**
* Export module API version (place this at the end of your module).
*
* @param module module name (f.e. hints)
*/
#define KR_MODULE_EXPORT(module) \
KR_EXPORT uint32_t module ## _api() { return KR_MODULE_API; }
#define KR_MODULE_API ((uint32_t) 0x20180401)
typedef uint32_t (module_api_cb)(void);
/**
* Module representation.
*
* The five symbols (init, ...) may be defined by the module as name_init(), etc;
* all are optional and missing symbols are represented as NULLs;
*/
struct kr_module {
char *name;
/** Constructor. Called after loading the module. @return error code. */
int (*init)(struct kr_module *self);
/** Destructor. Called before unloading the module. @return error code. */
int (*deinit)(struct kr_module *self);
/** Configure with encoded JSON (NULL if missing). @return error code. */
int (*config)(struct kr_module *self, const char *input);
/** Get a pointer to packet processing API specs. See docs on that type. */
const kr_layer_api_t * (*layer)(struct kr_module *self);
/** Get a pointer to list of properties, terminated by { NULL, NULL, NULL }. */
const struct kr_prop * (*props)(void);
void *lib; /**< Shared library handle or RTLD_DEFAULT */
void *data; /**< Custom data context. */
};
/**
* Module property callback. Input and output is passed via a JSON encoded in a string.
*
* @param env pointer to the lua engine, i.e. struct engine *env (TODO: explicit type)
* @param input parameter (NULL if missing/nil on lua level)
* @return a free-form JSON output (malloc-ated)
* @note see l_trampoline() implementation for details about the input/output conversion.
*/
typedef char *(kr_prop_cb)(void *env, struct kr_module *self, const char *input);
/**
* Module property (named callable).
*/
struct kr_prop {
kr_prop_cb *cb;
const char *name;
const char *info;
};
/**
* Load a C module instance into memory.
*
* @param module module structure
* @param name module name
* @param path module search path
* @return 0 or an error
*/
KR_EXPORT
int kr_module_load(struct kr_module *module, const char *name, const char *path);
/**
* Unload module instance.
*
* @param module module structure
*/
KR_EXPORT
void kr_module_unload(struct kr_module *module);
/**
* Get embedded module prototype by name (or NULL).
*/
KR_EXPORT
const struct kr_module * kr_module_embedded(const char *name);
|
