xref: /qemu/include/qemu/osdep.h (revision 226419d6)
1 /*
2  * OS includes and handling of OS dependencies
3  *
4  * This header exists to pull in some common system headers that
5  * most code in QEMU will want, and to fix up some possible issues with
6  * it (missing defines, Windows weirdness, and so on).
7  *
8  * To avoid getting into possible circular include dependencies, this
9  * file should not include any other QEMU headers, with the exceptions
10  * of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which
11  * are doing a similar job to this file and are under similar constraints.
12  *
13  * This header also contains prototypes for functions defined in
14  * os-*.c and util/oslib-*.c; those would probably be better split
15  * out into separate header files.
16  *
17  * In an ideal world this header would contain only:
18  *  (1) things which everybody needs
19  *  (2) things without which code would work on most platforms but
20  *      fail to compile or misbehave on a minority of host OSes
21  *
22  * This work is licensed under the terms of the GNU GPL, version 2 or later.
23  * See the COPYING file in the top-level directory.
24  */
25 #ifndef QEMU_OSDEP_H
26 #define QEMU_OSDEP_H
27 
28 #include "config-host.h"
29 #ifdef NEED_CPU_H
30 #include "config-target.h"
31 #endif
32 #include "qemu/compiler.h"
33 
34 /* Older versions of C++ don't get definitions of various macros from
35  * stdlib.h unless we define these macros before first inclusion of
36  * that system header.
37  */
38 #ifndef __STDC_CONSTANT_MACROS
39 #define __STDC_CONSTANT_MACROS
40 #endif
41 #ifndef __STDC_LIMIT_MACROS
42 #define __STDC_LIMIT_MACROS
43 #endif
44 #ifndef __STDC_FORMAT_MACROS
45 #define __STDC_FORMAT_MACROS
46 #endif
47 
48 /* The following block of code temporarily renames the daemon() function so the
49  * compiler does not see the warning associated with it in stdlib.h on OSX
50  */
51 #ifdef __APPLE__
52 #define daemon qemu_fake_daemon_function
53 #include <stdlib.h>
54 #undef daemon
55 extern int daemon(int, int);
56 #endif
57 
58 #include <stdarg.h>
59 #include <stddef.h>
60 #include <stdbool.h>
61 #include <stdint.h>
62 #include <sys/types.h>
63 #include <stdlib.h>
64 #include <stdio.h>
65 #include <string.h>
66 #include <strings.h>
67 #include <inttypes.h>
68 #include <limits.h>
69 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
70  * function availability on recentish Mingw-w64 platforms. */
71 #include <unistd.h>
72 #include <time.h>
73 #include <ctype.h>
74 #include <errno.h>
75 #include <fcntl.h>
76 #include <sys/stat.h>
77 #include <sys/time.h>
78 #include <assert.h>
79 #include <signal.h>
80 
81 #ifdef __OpenBSD__
82 #include <sys/signal.h>
83 #endif
84 
85 #ifndef _WIN32
86 #include <sys/wait.h>
87 #else
88 #define WIFEXITED(x)   1
89 #define WEXITSTATUS(x) (x)
90 #endif
91 
92 #ifdef _WIN32
93 #include "sysemu/os-win32.h"
94 #endif
95 
96 #ifdef CONFIG_POSIX
97 #include "sysemu/os-posix.h"
98 #endif
99 
100 #include "glib-compat.h"
101 
102 #include "qapi/error.h"
103 
104 #ifndef O_LARGEFILE
105 #define O_LARGEFILE 0
106 #endif
107 #ifndef O_BINARY
108 #define O_BINARY 0
109 #endif
110 #ifndef MAP_ANONYMOUS
111 #define MAP_ANONYMOUS MAP_ANON
112 #endif
113 #ifndef ENOMEDIUM
114 #define ENOMEDIUM ENODEV
115 #endif
116 #if !defined(ENOTSUP)
117 #define ENOTSUP 4096
118 #endif
119 #if !defined(ECANCELED)
120 #define ECANCELED 4097
121 #endif
122 #if !defined(EMEDIUMTYPE)
123 #define EMEDIUMTYPE 4098
124 #endif
125 #ifndef TIME_MAX
126 #define TIME_MAX LONG_MAX
127 #endif
128 
129 #ifndef MIN
130 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
131 #endif
132 #ifndef MAX
133 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
134 #endif
135 
136 /* Minimum function that returns zero only iff both values are zero.
137  * Intended for use with unsigned values only. */
138 #ifndef MIN_NON_ZERO
139 #define MIN_NON_ZERO(a, b) (((a) != 0 && (a) < (b)) ? (a) : (b))
140 #endif
141 
142 #ifndef ROUND_UP
143 #define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
144 #endif
145 
146 #ifndef DIV_ROUND_UP
147 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
148 #endif
149 
150 #ifndef ARRAY_SIZE
151 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
152 #endif
153 
154 int qemu_daemon(int nochdir, int noclose);
155 void *qemu_try_memalign(size_t alignment, size_t size);
156 void *qemu_memalign(size_t alignment, size_t size);
157 void *qemu_anon_ram_alloc(size_t size, uint64_t *align);
158 void qemu_vfree(void *ptr);
159 void qemu_anon_ram_free(void *ptr, size_t size);
160 
161 #define QEMU_MADV_INVALID -1
162 
163 #if defined(CONFIG_MADVISE)
164 
165 #include <sys/mman.h>
166 
167 #define QEMU_MADV_WILLNEED  MADV_WILLNEED
168 #define QEMU_MADV_DONTNEED  MADV_DONTNEED
169 #ifdef MADV_DONTFORK
170 #define QEMU_MADV_DONTFORK  MADV_DONTFORK
171 #else
172 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
173 #endif
174 #ifdef MADV_MERGEABLE
175 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE
176 #else
177 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
178 #endif
179 #ifdef MADV_UNMERGEABLE
180 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
181 #else
182 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
183 #endif
184 #ifdef MADV_DODUMP
185 #define QEMU_MADV_DODUMP MADV_DODUMP
186 #else
187 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
188 #endif
189 #ifdef MADV_DONTDUMP
190 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP
191 #else
192 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
193 #endif
194 #ifdef MADV_HUGEPAGE
195 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
196 #else
197 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
198 #endif
199 #ifdef MADV_NOHUGEPAGE
200 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
201 #else
202 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
203 #endif
204 
205 #elif defined(CONFIG_POSIX_MADVISE)
206 
207 #define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
208 #define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
209 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
210 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
211 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
212 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
213 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
214 #define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
215 #define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
216 
217 #else /* no-op */
218 
219 #define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
220 #define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
221 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
222 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
223 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
224 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
225 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
226 #define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
227 #define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
228 
229 #endif
230 
231 int qemu_madvise(void *addr, size_t len, int advice);
232 
233 int qemu_open(const char *name, int flags, ...);
234 int qemu_close(int fd);
235 
236 #if defined(__HAIKU__) && defined(__i386__)
237 #define FMT_pid "%ld"
238 #elif defined(WIN64)
239 #define FMT_pid "%" PRId64
240 #else
241 #define FMT_pid "%d"
242 #endif
243 
244 int qemu_create_pidfile(const char *filename);
245 int qemu_get_thread_id(void);
246 
247 #ifndef CONFIG_IOVEC
248 struct iovec {
249     void *iov_base;
250     size_t iov_len;
251 };
252 /*
253  * Use the same value as Linux for now.
254  */
255 #define IOV_MAX 1024
256 
257 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
258 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
259 #else
260 #include <sys/uio.h>
261 #endif
262 
263 #ifdef _WIN32
264 static inline void qemu_timersub(const struct timeval *val1,
265                                  const struct timeval *val2,
266                                  struct timeval *res)
267 {
268     res->tv_sec = val1->tv_sec - val2->tv_sec;
269     if (val1->tv_usec < val2->tv_usec) {
270         res->tv_sec--;
271         res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
272     } else {
273         res->tv_usec = val1->tv_usec - val2->tv_usec;
274     }
275 }
276 #else
277 #define qemu_timersub timersub
278 #endif
279 
280 void qemu_set_cloexec(int fd);
281 
282 /* QEMU "hardware version" setting. Used to replace code that exposed
283  * QEMU_VERSION to guests in the past and need to keep compatibilty.
284  * Do not use qemu_hw_version() in new code.
285  */
286 void qemu_set_hw_version(const char *);
287 const char *qemu_hw_version(void);
288 
289 void fips_set_state(bool requested);
290 bool fips_get_state(void);
291 
292 /* Return a dynamically allocated pathname denoting a file or directory that is
293  * appropriate for storing local state.
294  *
295  * @relative_pathname need not start with a directory separator; one will be
296  * added automatically.
297  *
298  * The caller is responsible for releasing the value returned with g_free()
299  * after use.
300  */
301 char *qemu_get_local_state_pathname(const char *relative_pathname);
302 
303 /* Find program directory, and save it for later usage with
304  * qemu_get_exec_dir().
305  * Try OS specific API first, if not working, parse from argv0. */
306 void qemu_init_exec_dir(const char *argv0);
307 
308 /* Get the saved exec dir.
309  * Caller needs to release the returned string by g_free() */
310 char *qemu_get_exec_dir(void);
311 
312 /**
313  * qemu_getauxval:
314  * @type: the auxiliary vector key to lookup
315  *
316  * Search the auxiliary vector for @type, returning the value
317  * or 0 if @type is not present.
318  */
319 unsigned long qemu_getauxval(unsigned long type);
320 
321 void qemu_set_tty_echo(int fd, bool echo);
322 
323 void os_mem_prealloc(int fd, char *area, size_t sz);
324 
325 int qemu_read_password(char *buf, int buf_size);
326 
327 /**
328  * qemu_fork:
329  *
330  * A version of fork that avoids signal handler race
331  * conditions that can lead to child process getting
332  * signals that are otherwise only expected by the
333  * parent. It also resets all signal handlers to the
334  * default settings.
335  *
336  * Returns 0 to child process, pid number to parent
337  * or -1 on failure.
338  */
339 pid_t qemu_fork(Error **errp);
340 
341 #endif
342