xref: /qemu/include/qemu/osdep.h (revision f348b6d1)
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, config-target.h, qemu/compiler.h,
11  * sysemu/os-posix.h, sysemu/os-win32.h, glib-compat.h and
12  * qemu/typedefs.h, all of which are doing a similar job to this file
13  * and are under similar constraints.
14  *
15  * This header also contains prototypes for functions defined in
16  * os-*.c and util/oslib-*.c; those would probably be better split
17  * out into separate header files.
18  *
19  * In an ideal world this header would contain only:
20  *  (1) things which everybody needs
21  *  (2) things without which code would work on most platforms but
22  *      fail to compile or misbehave on a minority of host OSes
23  *
24  * This work is licensed under the terms of the GNU GPL, version 2 or later.
25  * See the COPYING file in the top-level directory.
26  */
27 #ifndef QEMU_OSDEP_H
28 #define QEMU_OSDEP_H
29 
30 #include "config-host.h"
31 #ifdef NEED_CPU_H
32 #include "config-target.h"
33 #endif
34 #include "qemu/compiler.h"
35 
36 /* Older versions of C++ don't get definitions of various macros from
37  * stdlib.h unless we define these macros before first inclusion of
38  * that system header.
39  */
40 #ifndef __STDC_CONSTANT_MACROS
41 #define __STDC_CONSTANT_MACROS
42 #endif
43 #ifndef __STDC_LIMIT_MACROS
44 #define __STDC_LIMIT_MACROS
45 #endif
46 #ifndef __STDC_FORMAT_MACROS
47 #define __STDC_FORMAT_MACROS
48 #endif
49 
50 /* The following block of code temporarily renames the daemon() function so the
51  * compiler does not see the warning associated with it in stdlib.h on OSX
52  */
53 #ifdef __APPLE__
54 #define daemon qemu_fake_daemon_function
55 #include <stdlib.h>
56 #undef daemon
57 extern int daemon(int, int);
58 #endif
59 
60 #include <stdarg.h>
61 #include <stddef.h>
62 #include <stdbool.h>
63 #include <stdint.h>
64 #include <sys/types.h>
65 #include <stdlib.h>
66 #include <stdio.h>
67 #include <string.h>
68 #include <strings.h>
69 #include <inttypes.h>
70 #include <limits.h>
71 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
72  * function availability on recentish Mingw-w64 platforms. */
73 #include <unistd.h>
74 #include <time.h>
75 #include <ctype.h>
76 #include <errno.h>
77 #include <fcntl.h>
78 #include <sys/stat.h>
79 #include <sys/time.h>
80 #include <assert.h>
81 #include <signal.h>
82 
83 #ifdef __OpenBSD__
84 #include <sys/signal.h>
85 #endif
86 
87 #ifndef _WIN32
88 #include <sys/wait.h>
89 #else
90 #define WIFEXITED(x)   1
91 #define WEXITSTATUS(x) (x)
92 #endif
93 
94 #ifdef _WIN32
95 #include "sysemu/os-win32.h"
96 #endif
97 
98 #ifdef CONFIG_POSIX
99 #include "sysemu/os-posix.h"
100 #endif
101 
102 #include "glib-compat.h"
103 #include "qemu/typedefs.h"
104 
105 #ifndef O_LARGEFILE
106 #define O_LARGEFILE 0
107 #endif
108 #ifndef O_BINARY
109 #define O_BINARY 0
110 #endif
111 #ifndef MAP_ANONYMOUS
112 #define MAP_ANONYMOUS MAP_ANON
113 #endif
114 #ifndef ENOMEDIUM
115 #define ENOMEDIUM ENODEV
116 #endif
117 #if !defined(ENOTSUP)
118 #define ENOTSUP 4096
119 #endif
120 #if !defined(ECANCELED)
121 #define ECANCELED 4097
122 #endif
123 #if !defined(EMEDIUMTYPE)
124 #define EMEDIUMTYPE 4098
125 #endif
126 #ifndef TIME_MAX
127 #define TIME_MAX LONG_MAX
128 #endif
129 
130 /* HOST_LONG_BITS is the size of a native pointer in bits. */
131 #if UINTPTR_MAX == UINT32_MAX
132 # define HOST_LONG_BITS 32
133 #elif UINTPTR_MAX == UINT64_MAX
134 # define HOST_LONG_BITS 64
135 #else
136 # error Unknown pointer size
137 #endif
138 
139 #ifndef MIN
140 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
141 #endif
142 #ifndef MAX
143 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
144 #endif
145 
146 /* Minimum function that returns zero only iff both values are zero.
147  * Intended for use with unsigned values only. */
148 #ifndef MIN_NON_ZERO
149 #define MIN_NON_ZERO(a, b) (((a) != 0 && (a) < (b)) ? (a) : (b))
150 #endif
151 
152 /* Round number down to multiple */
153 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
154 
155 /* Round number up to multiple */
156 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
157 
158 #ifndef ROUND_UP
159 #define ROUND_UP(n,d) (((n) + (d) - 1) & -(d))
160 #endif
161 
162 #ifndef DIV_ROUND_UP
163 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
164 #endif
165 
166 #ifndef ARRAY_SIZE
167 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
168 #endif
169 
170 int qemu_daemon(int nochdir, int noclose);
171 void *qemu_try_memalign(size_t alignment, size_t size);
172 void *qemu_memalign(size_t alignment, size_t size);
173 void *qemu_anon_ram_alloc(size_t size, uint64_t *align);
174 void qemu_vfree(void *ptr);
175 void qemu_anon_ram_free(void *ptr, size_t size);
176 
177 #define QEMU_MADV_INVALID -1
178 
179 #if defined(CONFIG_MADVISE)
180 
181 #include <sys/mman.h>
182 
183 #define QEMU_MADV_WILLNEED  MADV_WILLNEED
184 #define QEMU_MADV_DONTNEED  MADV_DONTNEED
185 #ifdef MADV_DONTFORK
186 #define QEMU_MADV_DONTFORK  MADV_DONTFORK
187 #else
188 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
189 #endif
190 #ifdef MADV_MERGEABLE
191 #define QEMU_MADV_MERGEABLE MADV_MERGEABLE
192 #else
193 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
194 #endif
195 #ifdef MADV_UNMERGEABLE
196 #define QEMU_MADV_UNMERGEABLE MADV_UNMERGEABLE
197 #else
198 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
199 #endif
200 #ifdef MADV_DODUMP
201 #define QEMU_MADV_DODUMP MADV_DODUMP
202 #else
203 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
204 #endif
205 #ifdef MADV_DONTDUMP
206 #define QEMU_MADV_DONTDUMP MADV_DONTDUMP
207 #else
208 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
209 #endif
210 #ifdef MADV_HUGEPAGE
211 #define QEMU_MADV_HUGEPAGE MADV_HUGEPAGE
212 #else
213 #define QEMU_MADV_HUGEPAGE QEMU_MADV_INVALID
214 #endif
215 #ifdef MADV_NOHUGEPAGE
216 #define QEMU_MADV_NOHUGEPAGE MADV_NOHUGEPAGE
217 #else
218 #define QEMU_MADV_NOHUGEPAGE QEMU_MADV_INVALID
219 #endif
220 
221 #elif defined(CONFIG_POSIX_MADVISE)
222 
223 #define QEMU_MADV_WILLNEED  POSIX_MADV_WILLNEED
224 #define QEMU_MADV_DONTNEED  POSIX_MADV_DONTNEED
225 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
226 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
227 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
228 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
229 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
230 #define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
231 #define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
232 
233 #else /* no-op */
234 
235 #define QEMU_MADV_WILLNEED  QEMU_MADV_INVALID
236 #define QEMU_MADV_DONTNEED  QEMU_MADV_INVALID
237 #define QEMU_MADV_DONTFORK  QEMU_MADV_INVALID
238 #define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
239 #define QEMU_MADV_UNMERGEABLE QEMU_MADV_INVALID
240 #define QEMU_MADV_DODUMP QEMU_MADV_INVALID
241 #define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
242 #define QEMU_MADV_HUGEPAGE  QEMU_MADV_INVALID
243 #define QEMU_MADV_NOHUGEPAGE  QEMU_MADV_INVALID
244 
245 #endif
246 
247 int qemu_madvise(void *addr, size_t len, int advice);
248 
249 int qemu_open(const char *name, int flags, ...);
250 int qemu_close(int fd);
251 
252 #if defined(__HAIKU__) && defined(__i386__)
253 #define FMT_pid "%ld"
254 #elif defined(WIN64)
255 #define FMT_pid "%" PRId64
256 #else
257 #define FMT_pid "%d"
258 #endif
259 
260 int qemu_create_pidfile(const char *filename);
261 int qemu_get_thread_id(void);
262 
263 #ifndef CONFIG_IOVEC
264 struct iovec {
265     void *iov_base;
266     size_t iov_len;
267 };
268 /*
269  * Use the same value as Linux for now.
270  */
271 #define IOV_MAX 1024
272 
273 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
274 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
275 #else
276 #include <sys/uio.h>
277 #endif
278 
279 #ifdef _WIN32
280 static inline void qemu_timersub(const struct timeval *val1,
281                                  const struct timeval *val2,
282                                  struct timeval *res)
283 {
284     res->tv_sec = val1->tv_sec - val2->tv_sec;
285     if (val1->tv_usec < val2->tv_usec) {
286         res->tv_sec--;
287         res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
288     } else {
289         res->tv_usec = val1->tv_usec - val2->tv_usec;
290     }
291 }
292 #else
293 #define qemu_timersub timersub
294 #endif
295 
296 void qemu_set_cloexec(int fd);
297 
298 /* QEMU "hardware version" setting. Used to replace code that exposed
299  * QEMU_VERSION to guests in the past and need to keep compatibilty.
300  * Do not use qemu_hw_version() in new code.
301  */
302 void qemu_set_hw_version(const char *);
303 const char *qemu_hw_version(void);
304 
305 void fips_set_state(bool requested);
306 bool fips_get_state(void);
307 
308 /* Return a dynamically allocated pathname denoting a file or directory that is
309  * appropriate for storing local state.
310  *
311  * @relative_pathname need not start with a directory separator; one will be
312  * added automatically.
313  *
314  * The caller is responsible for releasing the value returned with g_free()
315  * after use.
316  */
317 char *qemu_get_local_state_pathname(const char *relative_pathname);
318 
319 /* Find program directory, and save it for later usage with
320  * qemu_get_exec_dir().
321  * Try OS specific API first, if not working, parse from argv0. */
322 void qemu_init_exec_dir(const char *argv0);
323 
324 /* Get the saved exec dir.
325  * Caller needs to release the returned string by g_free() */
326 char *qemu_get_exec_dir(void);
327 
328 /**
329  * qemu_getauxval:
330  * @type: the auxiliary vector key to lookup
331  *
332  * Search the auxiliary vector for @type, returning the value
333  * or 0 if @type is not present.
334  */
335 unsigned long qemu_getauxval(unsigned long type);
336 
337 void qemu_set_tty_echo(int fd, bool echo);
338 
339 void os_mem_prealloc(int fd, char *area, size_t sz);
340 
341 int qemu_read_password(char *buf, int buf_size);
342 
343 /**
344  * qemu_fork:
345  *
346  * A version of fork that avoids signal handler race
347  * conditions that can lead to child process getting
348  * signals that are otherwise only expected by the
349  * parent. It also resets all signal handlers to the
350  * default settings.
351  *
352  * Returns 0 to child process, pid number to parent
353  * or -1 on failure.
354  */
355 pid_t qemu_fork(Error **errp);
356 
357 #endif
358