exc.h revision 261363 
1/*
2 * Copyright (c) 2000-2001 Proofpoint, Inc. and its suppliers.
3 *	All rights reserved.
4 *
5 * By using this file, you agree to the terms and conditions set
6 * forth in the LICENSE file which can be found at the top level of
7 * the sendmail distribution.
8 *
9 *	$Id: exc.h,v 1.24 2013/11/22 20:51:31 ca Exp $
10 */
11
12/*
13**  libsm exception handling
14**  See libsm/exc.html for documentation.
15*/
16
17#ifndef SM_EXC_H
18# define SM_EXC_H
19
20#include <sm/setjmp.h>
21#include <sm/io.h>
22#include <sm/gen.h>
23#include <sm/assert.h>
24
25typedef struct sm_exc SM_EXC_T;
26typedef struct sm_exc_type SM_EXC_TYPE_T;
27typedef union sm_val SM_VAL_T;
28
29/*
30**  Exception types
31*/
32
33extern const char SmExcTypeMagic[];
34
35struct sm_exc_type
36{
37	const char	*sm_magic;
38	const char	*etype_category;
39	const char	*etype_argformat;
40	void		(*etype_print) __P((SM_EXC_T *, SM_FILE_T *));
41	const char	*etype_printcontext;
42};
43
44extern const SM_EXC_TYPE_T SmEtypeOs;
45extern const SM_EXC_TYPE_T SmEtypeErr;
46
47extern void
48sm_etype_printf __P((
49	SM_EXC_T *_exc,
50	SM_FILE_T *_stream));
51
52/*
53**  Exception objects
54*/
55
56extern const char SmExcMagic[];
57
58union sm_val
59{
60	int		v_int;
61	long		v_long;
62	char		*v_str;
63	SM_EXC_T	*v_exc;
64};
65
66struct sm_exc
67{
68	const char		*sm_magic;
69	size_t			exc_refcount;
70	const SM_EXC_TYPE_T	*exc_type;
71	SM_VAL_T		*exc_argv;
72};
73
74# define SM_EXC_INITIALIZER(type, argv) \
75	{ \
76		SmExcMagic, \
77		0, \
78		type, \
79		argv, \
80	}
81
82extern SM_EXC_T *
83sm_exc_new_x __P((
84	const SM_EXC_TYPE_T *_type,
85	...));
86
87extern SM_EXC_T *
88sm_exc_addref __P((
89	SM_EXC_T *_exc));
90
91extern void
92sm_exc_free __P((
93	SM_EXC_T *_exc));
94
95extern bool
96sm_exc_match __P((
97	SM_EXC_T *_exc,
98	const char *_pattern));
99
100extern void
101sm_exc_write __P((
102	SM_EXC_T *_exc,
103	SM_FILE_T *_stream));
104
105extern void
106sm_exc_print __P((
107	SM_EXC_T *_exc,
108	SM_FILE_T *_stream));
109
110extern SM_DEAD(void
111sm_exc_raise_x __P((
112	SM_EXC_T *_exc)));
113
114extern SM_DEAD(void
115sm_exc_raisenew_x __P((
116	const SM_EXC_TYPE_T *_type,
117	...)));
118
119/*
120**  Exception handling
121*/
122
123typedef void (*SM_EXC_DEFAULT_HANDLER_T) __P((SM_EXC_T *));
124
125extern void
126sm_exc_newthread __P((
127	SM_EXC_DEFAULT_HANDLER_T _handle));
128
129typedef struct sm_exc_handler SM_EXC_HANDLER_T;
130struct sm_exc_handler
131{
132	SM_EXC_T		*eh_value;
133	SM_JMPBUF_T		eh_context;
134	SM_EXC_HANDLER_T	*eh_parent;
135	int			eh_state;
136};
137
138/* values for eh_state */
139enum
140{
141	SM_EH_PUSHED = 2,
142	SM_EH_POPPED = 0,
143	SM_EH_HANDLED = 1
144};
145
146extern SM_EXC_HANDLER_T *SmExcHandler;
147
148# define SM_TRY		{ SM_EXC_HANDLER_T _h; \
149			  do { \
150			    _h.eh_value = NULL; \
151			    _h.eh_parent = SmExcHandler; \
152			    _h.eh_state = SM_EH_PUSHED; \
153			    SmExcHandler = &_h; \
154			    if (sm_setjmp_nosig(_h.eh_context) == 0) {
155
156# define SM_FINALLY	      SM_ASSERT(SmExcHandler == &_h); \
157			    } \
158			    if (sm_setjmp_nosig(_h.eh_context) == 0) {
159
160# define SM_EXCEPT(e,pat)   } \
161			    if (_h.eh_state == SM_EH_HANDLED) \
162			      break; \
163			    if (_h.eh_state == SM_EH_PUSHED) { \
164			      SM_ASSERT(SmExcHandler == &_h); \
165			      SmExcHandler = _h.eh_parent; \
166			    } \
167			    _h.eh_state = sm_exc_match(_h.eh_value,pat) \
168			      ? SM_EH_HANDLED : SM_EH_POPPED; \
169			    if (_h.eh_state == SM_EH_HANDLED) { \
170			      SM_UNUSED(SM_EXC_T *e) = _h.eh_value;
171
172# define SM_END_TRY	  } \
173			  } while (0); \
174			  if (_h.eh_state == SM_EH_PUSHED) { \
175			    SM_ASSERT(SmExcHandler == &_h); \
176			    SmExcHandler = _h.eh_parent; \
177			    if (_h.eh_value != NULL) \
178			      sm_exc_raise_x(_h.eh_value); \
179			  } else if (_h.eh_state == SM_EH_POPPED) { \
180			    if (_h.eh_value != NULL) \
181			      sm_exc_raise_x(_h.eh_value); \
182			  } else \
183			    sm_exc_free(_h.eh_value); \
184			}
185
186#endif /* SM_EXC_H */
187