make more functions available externally
[project/uci.git] / uci_internal.h
1 /*
2 * libuci - Library for the Unified Configuration Interface
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License version 2.1
7 * as published by the Free Software Foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 #ifndef __UCI_INTERNAL_H
16 #define __UCI_INTERNAL_H
17
18 struct uci_parse_context
19 {
20 /* error context */
21 const char *reason;
22 int line;
23 int byte;
24
25 /* private: */
26 struct uci_package *package;
27 struct uci_section *section;
28 bool merge;
29 FILE *file;
30 const char *name;
31 char *buf;
32 int bufsz;
33 };
34
35 int uci_add_backend(struct uci_context *ctx, struct uci_backend *b);
36 void uci_add_history(struct uci_context *ctx, struct uci_list *list, int cmd, char *section, char *option, char *value);
37 void uci_free_history(struct uci_history *h);
38
39 /*
40 * functions for debug and error handling, for internal use only
41 */
42
43 #ifdef UCI_DEBUG
44 #define DPRINTF(...) fprintf(stderr, __VA_ARGS__)
45 #else
46 #define DPRINTF(...)
47 #endif
48
49 /*
50 * throw an uci exception and store the error number
51 * in the context.
52 */
53 #define UCI_THROW(ctx, err) do { \
54 DPRINTF("Exception: %s in %s, %s:%d\n", #err, __func__, __FILE__, __LINE__); \
55 longjmp(ctx->trap, err); \
56 } while (0)
57
58 /*
59 * store the return address for handling exceptions
60 * needs to be called in every externally visible library function
61 *
62 * NB: this does not handle recursion at all. Calling externally visible
63 * functions from other uci functions is only allowed at the end of the
64 * calling function, or by wrapping the function call in UCI_TRAP_SAVE
65 * and UCI_TRAP_RESTORE.
66 */
67 #define UCI_HANDLE_ERR(ctx) do { \
68 DPRINTF("ENTER: %s\n", __func__); \
69 int __val = 0; \
70 ctx->errno = 0; \
71 if (!ctx) \
72 return UCI_ERR_INVAL; \
73 if (!ctx->internal) \
74 __val = setjmp(ctx->trap); \
75 ctx->internal = false; \
76 if (__val) { \
77 DPRINTF("LEAVE: %s, ret=%d\n", __func__, __val); \
78 ctx->errno = __val; \
79 return __val; \
80 } \
81 } while (0)
82
83 /*
84 * In a block enclosed by UCI_TRAP_SAVE and UCI_TRAP_RESTORE, all exceptions
85 * are intercepted and redirected to the label specified in 'handler'
86 * after UCI_TRAP_RESTORE, or when reaching the 'handler' label, the old
87 * exception handler is restored
88 */
89 #define UCI_TRAP_SAVE(ctx, handler) do { \
90 jmp_buf __old_trap; \
91 int __val; \
92 memcpy(__old_trap, ctx->trap, sizeof(ctx->trap)); \
93 __val = setjmp(ctx->trap); \
94 if (__val) { \
95 ctx->errno = __val; \
96 memcpy(ctx->trap, __old_trap, sizeof(ctx->trap)); \
97 goto handler; \
98 }
99 #define UCI_TRAP_RESTORE(ctx) \
100 memcpy(ctx->trap, __old_trap, sizeof(ctx->trap)); \
101 } while(0)
102
103 /**
104 * UCI_INTERNAL: Do an internal call of a public API function
105 *
106 * Sets Exception handling to passthrough mode.
107 * Allows API functions to change behavior compared to public use
108 */
109 #define UCI_INTERNAL(func, ctx, ...) do { \
110 ctx->internal = true; \
111 func(ctx, __VA_ARGS__); \
112 } while (0)
113
114 /*
115 * check the specified condition.
116 * throw an invalid argument exception if it's false
117 */
118 #define UCI_ASSERT(ctx, expr) do { \
119 if (!(expr)) { \
120 DPRINTF("[%s:%d] Assertion failed\n", __FILE__, __LINE__); \
121 UCI_THROW(ctx, UCI_ERR_INVAL); \
122 } \
123 } while (0)
124
125 #endif