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6ec2e0f5 | 1 | /* Invalid parameter handler for MSVC runtime libraries. |
c0c3707f | 2 | Copyright (C) 2011-2019 Free Software Foundation, Inc. |
6ec2e0f5 SDJ |
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 | |
c0c3707f | 15 | with this program; if not, see <https://www.gnu.org/licenses/>. */ |
6ec2e0f5 SDJ |
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 | |
c0c3707f | 98 | <https://docs.microsoft.com/en-us/cpp/cpp/raising-software-exceptions>. |
6ec2e0f5 SDJ |
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 | |
c0c3707f | 109 | <https://docs.microsoft.com/en-us/cpp/cpp/try-except-statement>. |
6ec2e0f5 SDJ |
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 */ |