dhcpd-pools  2.28
ISC dhcpd lease usage analyser
msvc-inval.h
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1 /* Invalid parameter handler for MSVC runtime libraries.
2  Copyright (C) 2011-2015 Free Software Foundation, Inc.
3 
4  This program is free software; you can redistribute it and/or modify
5  it under the terms of the GNU General Public License as published by
6  the Free Software Foundation; either version 3, or (at your option)
7  any later version.
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  You should have received a copy of the GNU General Public License along
15  with this program; if not, see <http://www.gnu.org/licenses/>. */
16 
17 #ifndef _MSVC_INVAL_H
18 #define _MSVC_INVAL_H
19 
20 /* With MSVC runtime libraries with the "invalid parameter handler" concept,
21  functions like fprintf(), dup2(), or close() crash when the caller passes
22  an invalid argument. But POSIX wants error codes (such as EINVAL or EBADF)
23  instead.
24  This file defines macros that turn such an invalid parameter notification
25  into a non-local exit. An error code can then be produced at the target
26  of this exit. You can thus write code like
27 
28  TRY_MSVC_INVAL
29  {
30  <Code that can trigger an invalid parameter notification
31  but does not do 'return', 'break', 'continue', nor 'goto'.>
32  }
33  CATCH_MSVC_INVAL
34  {
35  <Code that handles an invalid parameter notification
36  but does not do 'return', 'break', 'continue', nor 'goto'.>
37  }
38  DONE_MSVC_INVAL;
39 
40  This entire block expands to a single statement.
41 
42  The handling of invalid parameters can be done in three ways:
43 
44  * The default way, which is reasonable for programs (not libraries):
45  AC_DEFINE([MSVC_INVALID_PARAMETER_HANDLING], [DEFAULT_HANDLING])
46 
47  * The way for libraries that make "hairy" calls (like close(-1), or
48  fclose(fp) where fileno(fp) is closed, or simply getdtablesize()):
49  AC_DEFINE([MSVC_INVALID_PARAMETER_HANDLING], [HAIRY_LIBRARY_HANDLING])
50 
51  * The way for libraries that make no "hairy" calls:
52  AC_DEFINE([MSVC_INVALID_PARAMETER_HANDLING], [SANE_LIBRARY_HANDLING])
53  */
54 
55 #define DEFAULT_HANDLING 0
56 #define HAIRY_LIBRARY_HANDLING 1
57 #define SANE_LIBRARY_HANDLING 2
58 
59 #if HAVE_MSVC_INVALID_PARAMETER_HANDLER \
60  && !(MSVC_INVALID_PARAMETER_HANDLING == SANE_LIBRARY_HANDLING)
61 /* A native Windows platform with the "invalid parameter handler" concept,
62  and either DEFAULT_HANDLING or HAIRY_LIBRARY_HANDLING. */
63 
64 # if MSVC_INVALID_PARAMETER_HANDLING == DEFAULT_HANDLING
65 /* Default handling. */
66 
67 # ifdef __cplusplus
68 extern "C" {
69 # endif
70 
71 /* Ensure that the invalid parameter handler in installed that just returns.
72  Because we assume no other part of the program installs a different
73  invalid parameter handler, this solution is multithread-safe. */
74 extern void gl_msvc_inval_ensure_handler (void);
75 
76 # ifdef __cplusplus
77 }
78 # endif
79 
80 # define TRY_MSVC_INVAL \
81  do \
82  { \
83  gl_msvc_inval_ensure_handler (); \
84  if (1)
85 # define CATCH_MSVC_INVAL \
86  else
87 # define DONE_MSVC_INVAL \
88  } \
89  while (0)
90 
91 # else
92 /* Handling for hairy libraries. */
93 
94 # include <excpt.h>
95 
96 /* Gnulib can define its own status codes, as described in the page
97  "Raising Software Exceptions" on microsoft.com
98  <http://msdn.microsoft.com/en-us/library/het71c37.aspx>.
99  Our status codes are composed of
100  - 0xE0000000, mandatory for all user-defined status codes,
101  - 0x474E550, a API identifier ("GNU"),
102  - 0, 1, 2, ..., used to distinguish different status codes from the
103  same API. */
104 # define STATUS_GNULIB_INVALID_PARAMETER (0xE0000000 + 0x474E550 + 0)
105 
106 # if defined _MSC_VER
107 /* A compiler that supports __try/__except, as described in the page
108  "try-except statement" on microsoft.com
109  <http://msdn.microsoft.com/en-us/library/s58ftw19.aspx>.
110  With __try/__except, we can use the multithread-safe exception handling. */
111 
112 # ifdef __cplusplus
113 extern "C" {
114 # endif
115 
116 /* Ensure that the invalid parameter handler in installed that raises a
117  software exception with code STATUS_GNULIB_INVALID_PARAMETER.
118  Because we assume no other part of the program installs a different
119  invalid parameter handler, this solution is multithread-safe. */
120 extern void gl_msvc_inval_ensure_handler (void);
121 
122 # ifdef __cplusplus
123 }
124 # endif
125 
126 # define TRY_MSVC_INVAL \
127  do \
128  { \
129  gl_msvc_inval_ensure_handler (); \
130  __try
131 # define CATCH_MSVC_INVAL \
132  __except (GetExceptionCode () == STATUS_GNULIB_INVALID_PARAMETER \
133  ? EXCEPTION_EXECUTE_HANDLER \
134  : EXCEPTION_CONTINUE_SEARCH)
135 # define DONE_MSVC_INVAL \
136  } \
137  while (0)
138 
139 # else
140 /* Any compiler.
141  We can only use setjmp/longjmp. */
142 
143 # include <setjmp.h>
144 
145 # ifdef __cplusplus
146 extern "C" {
147 # endif
148 
149 struct gl_msvc_inval_per_thread
150 {
151  /* The restart that will resume execution at the code between
152  CATCH_MSVC_INVAL and DONE_MSVC_INVAL. It is enabled only between
153  TRY_MSVC_INVAL and CATCH_MSVC_INVAL. */
154  jmp_buf restart;
155 
156  /* Tells whether the contents of restart is valid. */
157  int restart_valid;
158 };
159 
160 /* Ensure that the invalid parameter handler in installed that passes
161  control to the gl_msvc_inval_restart if it is valid, or raises a
162  software exception with code STATUS_GNULIB_INVALID_PARAMETER otherwise.
163  Because we assume no other part of the program installs a different
164  invalid parameter handler, this solution is multithread-safe. */
165 extern void gl_msvc_inval_ensure_handler (void);
166 
167 /* Return a pointer to the per-thread data for the current thread. */
168 extern struct gl_msvc_inval_per_thread *gl_msvc_inval_current (void);
169 
170 # ifdef __cplusplus
171 }
172 # endif
173 
174 # define TRY_MSVC_INVAL \
175  do \
176  { \
177  struct gl_msvc_inval_per_thread *msvc_inval_current; \
178  gl_msvc_inval_ensure_handler (); \
179  msvc_inval_current = gl_msvc_inval_current (); \
180  /* First, initialize gl_msvc_inval_restart. */ \
181  if (setjmp (msvc_inval_current->restart) == 0) \
182  { \
183  /* Then, mark it as valid. */ \
184  msvc_inval_current->restart_valid = 1;
185 # define CATCH_MSVC_INVAL \
186  /* Execution completed. \
187  Mark gl_msvc_inval_restart as invalid. */ \
188  msvc_inval_current->restart_valid = 0; \
189  } \
190  else \
191  { \
192  /* Execution triggered an invalid parameter notification. \
193  Mark gl_msvc_inval_restart as invalid. */ \
194  msvc_inval_current->restart_valid = 0;
195 # define DONE_MSVC_INVAL \
196  } \
197  } \
198  while (0)
199 
200 # endif
201 
202 # endif
203 
204 #else
205 /* A platform that does not need to the invalid parameter handler,
206  or when SANE_LIBRARY_HANDLING is desired. */
207 
208 /* The braces here avoid GCC warnings like
209  "warning: suggest explicit braces to avoid ambiguous 'else'". */
210 # define TRY_MSVC_INVAL \
211  do \
212  { \
213  if (1)
214 # define CATCH_MSVC_INVAL \
215  else
216 # define DONE_MSVC_INVAL \
217  } \
218  while (0)
219 
220 #endif
221 
222 #endif /* _MSVC_INVAL_H */