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 * system/os-posix.h, system/os-win32.h, system/os-wasm.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 #if !defined _FORTIFY_SOURCE && defined __OPTIMIZE__ && __OPTIMIZE__ && defined __linux__
31 # define _FORTIFY_SOURCE 2
32 #endif
33
34 #include "config-host.h"
35 #ifdef COMPILING_PER_TARGET
36 #include CONFIG_TARGET
37 #else
38 #include "exec/poison.h"
39 #endif
40
41 /*
42 * HOST_WORDS_BIGENDIAN was replaced with HOST_BIG_ENDIAN. Prevent it from
43 * creeping back in.
44 */
45 #pragma GCC poison HOST_WORDS_BIGENDIAN
46
47 /*
48 * TARGET_WORDS_BIGENDIAN was replaced with TARGET_BIG_ENDIAN. Prevent it from
49 * creeping back in.
50 */
51 #pragma GCC poison TARGET_WORDS_BIGENDIAN
52
53 #include "qemu/compiler.h"
54
55 /* Older versions of C++ don't get definitions of various macros from
56 * stdlib.h unless we define these macros before first inclusion of
57 * that system header.
58 */
59 #ifndef __STDC_CONSTANT_MACROS
60 #define __STDC_CONSTANT_MACROS
61 #endif
62 #ifndef __STDC_LIMIT_MACROS
63 #define __STDC_LIMIT_MACROS
64 #endif
65 #ifndef __STDC_FORMAT_MACROS
66 #define __STDC_FORMAT_MACROS
67 #endif
68
69 /* The following block of code temporarily renames the daemon() function so the
70 * compiler does not see the warning associated with it in stdlib.h on OSX
71 */
72 #ifdef __APPLE__
73 #define daemon qemu_fake_daemon_function
74 #include <stdlib.h>
75 #undef daemon
76 QEMU_EXTERN_C int daemon(int, int);
77 #endif
78
79 #ifdef _WIN32
80 /* as defined in sdkddkver.h */
81 #ifndef _WIN32_WINNT
82 #define _WIN32_WINNT 0x0602 /* Windows 8 API (should be >= the one from glib) */
83 #endif
84 /* reduces the number of implicitly included headers */
85 #ifndef WIN32_LEAN_AND_MEAN
86 #define WIN32_LEAN_AND_MEAN
87 #endif
88 #endif
89
90 /* enable C99/POSIX format strings (needs mingw32-runtime 3.15 or later) */
91 #ifdef __MINGW32__
92 #define __USE_MINGW_ANSI_STDIO 1
93 #endif
94
95 /*
96 * We need the FreeBSD "legacy" definitions. Rust needs the FreeBSD 11 system
97 * calls since it doesn't use libc at all, so we have to emulate that despite
98 * FreeBSD 11 being EOL'd.
99 */
100 #ifdef __FreeBSD__
101 #define _WANT_FREEBSD11_STAT
102 #define _WANT_FREEBSD11_STATFS
103 #define _WANT_FREEBSD11_DIRENT
104 #define _WANT_KERNEL_ERRNO
105 #define _WANT_SEMUN
106 #endif
107
108 #include <stdarg.h>
109 #include <stddef.h>
110 #include <stdbool.h>
111 #include <stdint.h>
112 #include <sys/types.h>
113 #include <stdlib.h>
114 #include <stdio.h>
115
116 #include <string.h>
117 #include <strings.h>
118 #include <inttypes.h>
119 #include <limits.h>
120 /* Put unistd.h before time.h as that triggers localtime_r/gmtime_r
121 * function availability on recentish Mingw-w64 platforms. */
122 #include <unistd.h>
123 #include <time.h>
124 #include <ctype.h>
125 #include <errno.h>
126 #include <fcntl.h>
127 #include <getopt.h>
128 #include <sys/stat.h>
129 #include <sys/time.h>
130 #include <assert.h>
131 /* setjmp must be declared before system/os-win32.h
132 * because it is redefined there. */
133 #include <setjmp.h>
134 #include <signal.h>
135
136 #ifdef CONFIG_IOVEC
137 #include <sys/uio.h>
138 #endif
139
140 #if defined(__linux__) && defined(__sparc__)
141 /* The SPARC definition of QEMU_VMALLOC_ALIGN needs SHMLBA */
142 #include <sys/shm.h>
143 #endif
144
145 #ifndef _WIN32
146 #include <sys/wait.h>
147 #else
148 #define WIFEXITED(x) 1
149 #define WEXITSTATUS(x) (x)
150 #endif
151
152 #ifdef __APPLE__
153 #include <AvailabilityMacros.h>
154 #endif
155
156 /*
157 * This is somewhat like a system header; it must be outside any extern "C"
158 * block because it includes system headers itself, including glib.h,
159 * which will not compile if inside an extern "C" block.
160 */
161 #include "glib-compat.h"
162
163 #ifdef _WIN32
164 #include "system/os-win32.h"
165 #endif
166
167 #if defined(CONFIG_POSIX) && !defined(EMSCRIPTEN)
168 #include "system/os-posix.h"
169 #endif
170
171 #if defined(EMSCRIPTEN)
172 #include "system/os-wasm.h"
173 #endif
174
175 #ifdef __cplusplus
176 extern "C" {
177 #endif
178
179 #include "qemu/typedefs.h"
180
181 /**
182 * Mark a function that executes in coroutine context
183 *
184 * Functions that execute in coroutine context cannot be called directly from
185 * normal functions. In the future it would be nice to enable compiler or
186 * static checker support for catching such errors. This annotation might make
187 * it possible and in the meantime it serves as documentation.
188 *
189 * For example:
190 *
191 * static void coroutine_fn foo(void) {
192 * ....
193 * }
194 */
195 #ifdef __clang__
196 #define coroutine_fn QEMU_ANNOTATE("coroutine_fn")
197 #else
198 #define coroutine_fn
199 #endif
200
201 /**
202 * Mark a function that can suspend when executed in coroutine context,
203 * but can handle running in non-coroutine context too.
204 */
205 #ifdef __clang__
206 #define coroutine_mixed_fn QEMU_ANNOTATE("coroutine_mixed_fn")
207 #else
208 #define coroutine_mixed_fn
209 #endif
210
211 /**
212 * Mark a function that should not be called from a coroutine context.
213 * Usually there will be an analogous, coroutine_fn function that should
214 * be used instead.
215 *
216 * When the function is also marked as coroutine_mixed_fn, the function should
217 * only be called if the caller does not know whether it is in coroutine
218 * context.
219 *
220 * Functions that are only no_coroutine_fn, on the other hand, should not
221 * be called from within coroutines at all. This for example includes
222 * functions that block.
223 *
224 * In the future it would be nice to enable compiler or static checker
225 * support for catching such errors. This annotation is the first step
226 * towards this, and in the meantime it serves as documentation.
227 *
228 * For example:
229 *
230 * static void no_coroutine_fn foo(void) {
231 * ....
232 * }
233 */
234 #ifdef __clang__
235 #define no_coroutine_fn QEMU_ANNOTATE("no_coroutine_fn")
236 #else
237 #define no_coroutine_fn
238 #endif
239
240
241 /*
242 * For mingw, as of v6.0.0, the function implementing the assert macro is
243 * not marked as noreturn, so the compiler cannot delete code following an
244 * assert(false) as unused. We rely on this within the code base to delete
245 * code that is unreachable when features are disabled.
246 * All supported versions of Glib's g_assert() satisfy this requirement.
247 */
248 #ifdef __MINGW32__
249 #undef assert
250 #define assert(x) g_assert(x)
251 #endif
252
253 /**
254 * qemu_build_not_reached()
255 *
256 * The compiler, during optimization, is expected to prove that a call
257 * to this function cannot be reached and remove it. If the compiler
258 * supports QEMU_ERROR, this will be reported at compile time; otherwise
259 * this will be reported at link time due to the missing symbol.
260 */
261 G_NORETURN
262 void QEMU_ERROR("code path is reachable")
263 qemu_build_not_reached_always(void);
264 #if defined(__OPTIMIZE__) && !defined(__NO_INLINE__)
265 #define qemu_build_not_reached() qemu_build_not_reached_always()
266 #else
267 #define qemu_build_not_reached() g_assert_not_reached()
268 #endif
269
270 /**
271 * qemu_build_assert()
272 *
273 * The compiler, during optimization, is expected to prove that the
274 * assertion is true.
275 */
276 #define qemu_build_assert(test) while (!(test)) qemu_build_not_reached()
277
278 /*
279 * According to waitpid man page:
280 * WCOREDUMP
281 * This macro is not specified in POSIX.1-2001 and is not
282 * available on some UNIX implementations (e.g., AIX, SunOS).
283 * Therefore, enclose its use inside #ifdef WCOREDUMP ... #endif.
284 */
285 #ifndef WCOREDUMP
286 #define WCOREDUMP(status) 0
287 #endif
288 /*
289 * We have a lot of unaudited code that may fail in strange ways, or
290 * even be a security risk during migration, if you disable assertions
291 * at compile-time. You may comment out these safety checks if you
292 * absolutely want to disable assertion overhead, but it is not
293 * supported upstream so the risk is all yours. Meanwhile, please
294 * submit patches to remove any side-effects inside an assertion, or
295 * fixing error handling that should use Error instead of assert.
296 */
297 #ifdef NDEBUG
298 #error building with NDEBUG is not supported
299 #endif
300 #ifdef G_DISABLE_ASSERT
301 #error building with G_DISABLE_ASSERT is not supported
302 #endif
303
304 #ifndef OFF_MAX
305 #define OFF_MAX (sizeof (off_t) == 8 ? INT64_MAX : INT32_MAX)
306 #endif
307
308 #ifndef O_LARGEFILE
309 #define O_LARGEFILE 0
310 #endif
311 #ifndef O_BINARY
312 #define O_BINARY 0
313 #endif
314 #ifndef MAP_ANONYMOUS
315 #define MAP_ANONYMOUS MAP_ANON
316 #endif
317 #ifndef MAP_NORESERVE
318 #define MAP_NORESERVE 0
319 #endif
320 #ifndef ENOMEDIUM
321 #define ENOMEDIUM ENODEV
322 #endif
323 #if !defined(ENOTSUP)
324 #define ENOTSUP 4096
325 #endif
326 #if !defined(ECANCELED)
327 #define ECANCELED 4097
328 #endif
329 #if !defined(EMEDIUMTYPE)
330 #define EMEDIUMTYPE 4098
331 #endif
332 #if !defined(ESHUTDOWN)
333 #define ESHUTDOWN 4099
334 #endif
335
336 #define RETRY_ON_EINTR(expr) \
337 (__extension__ \
338 ({ typeof(expr) __result; \
339 do { \
340 __result = (expr); \
341 } while (__result == -1 && errno == EINTR); \
342 __result; }))
343
344 /* time_t may be either 32 or 64 bits depending on the host OS, and
345 * can be either signed or unsigned, so we can't just hardcode a
346 * specific maximum value. This is not a C preprocessor constant,
347 * so you can't use TIME_MAX in an #ifdef, but for our purposes
348 * this isn't a problem.
349 */
350
351 /* The macros TYPE_SIGNED, TYPE_WIDTH, and TYPE_MAXIMUM are from
352 * Gnulib, and are under the LGPL v2.1 or (at your option) any
353 * later version.
354 */
355
356 /* True if the real type T is signed. */
357 #define TYPE_SIGNED(t) (!((t)0 < (t)-1))
358
359 /* The width in bits of the integer type or expression T.
360 * Padding bits are not supported.
361 */
362 #define TYPE_WIDTH(t) (sizeof(t) * CHAR_BIT)
363
364 /* The maximum and minimum values for the integer type T. */
365 #define TYPE_MAXIMUM(t) \
366 ((t) (!TYPE_SIGNED(t) \
367 ? (t)-1 \
368 : ((((t)1 << (TYPE_WIDTH(t) - 2)) - 1) * 2 + 1)))
369
370 #ifndef TIME_MAX
371 #define TIME_MAX TYPE_MAXIMUM(time_t)
372 #endif
373
374 /* Mac OSX has a <stdint.h> bug that incorrectly defines SIZE_MAX with
375 * the wrong type. Our replacement isn't usable in preprocessor
376 * expressions, but it is sufficient for our needs. */
377 #ifdef HAVE_BROKEN_SIZE_MAX
378 #undef SIZE_MAX
379 #define SIZE_MAX ((size_t)-1)
380 #endif
381
382 /*
383 * Two variations of MIN/MAX macros. The first is for runtime use, and
384 * evaluates arguments only once (so it is safe even with side
385 * effects), but will not work in constant contexts (such as array
386 * size declarations) because of the '{}'. The second is for constant
387 * expression use, where evaluating arguments twice is safe because
388 * the result is going to be constant anyway, but will not work in a
389 * runtime context because of a void expression where a value is
390 * expected. Thus, both gcc and clang will fail to compile if you use
391 * the wrong macro (even if the error may seem a bit cryptic).
392 *
393 * Note that neither form is usable as an #if condition; if you truly
394 * need to write conditional code that depends on a minimum or maximum
395 * determined by the pre-processor instead of the compiler, you'll
396 * have to open-code it. Sadly, Coverity is severely confused by the
397 * constant variants, so we have to dumb things down there.
398 *
399 * Preprocessor sorcery ahead: use different identifiers for the local
400 * variables in each expansion, so we can nest macro calls without
401 * shadowing variables.
402 */
403 #define MIN_INTERNAL(a, b, _a, _b) \
404 ({ \
405 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \
406 _a < _b ? _a : _b; \
407 })
408 #undef MIN
409 #define MIN(a, b) \
410 MIN_INTERNAL((a), (b), MAKE_IDENTIFIER(_a), MAKE_IDENTIFIER(_b))
411
412 #define MAX_INTERNAL(a, b, _a, _b) \
413 ({ \
414 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \
415 _a > _b ? _a : _b; \
416 })
417 #undef MAX
418 #define MAX(a, b) \
419 MAX_INTERNAL((a), (b), MAKE_IDENTIFIER(_a), MAKE_IDENTIFIER(_b))
420
421 #ifdef __COVERITY__
422 # define MIN_CONST(a, b) ((a) < (b) ? (a) : (b))
423 # define MAX_CONST(a, b) ((a) > (b) ? (a) : (b))
424 #else
425 # define MIN_CONST(a, b) \
426 __builtin_choose_expr( \
427 __builtin_constant_p(a) && __builtin_constant_p(b), \
428 (a) < (b) ? (a) : (b), \
429 ((void)0))
430 # define MAX_CONST(a, b) \
431 __builtin_choose_expr( \
432 __builtin_constant_p(a) && __builtin_constant_p(b), \
433 (a) > (b) ? (a) : (b), \
434 ((void)0))
435 #endif
436
437 /*
438 * Minimum function that returns zero only if both values are zero.
439 * Intended for use with unsigned values only.
440 *
441 * Preprocessor sorcery ahead: use different identifiers for the local
442 * variables in each expansion, so we can nest macro calls without
443 * shadowing variables.
444 */
445 #define MIN_NON_ZERO_INTERNAL(a, b, _a, _b) \
446 ({ \
447 typeof(1 ? (a) : (b)) _a = (a), _b = (b); \
448 _a == 0 ? _b : (_b == 0 || _b > _a) ? _a : _b; \
449 })
450 #define MIN_NON_ZERO(a, b) \
451 MIN_NON_ZERO_INTERNAL((a), (b), MAKE_IDENTIFIER(_a), MAKE_IDENTIFIER(_b))
452
453 /*
454 * Round number down to multiple. Safe when m is not a power of 2 (see
455 * ROUND_DOWN for a faster version when a power of 2 is guaranteed).
456 */
457 #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))
458
459 /*
460 * Round number up to multiple. Safe when m is not a power of 2 (see
461 * ROUND_UP for a faster version when a power of 2 is guaranteed).
462 */
463 #define QEMU_ALIGN_UP(n, m) QEMU_ALIGN_DOWN((n) + (m) - 1, (m))
464
465 /* Check if n is a multiple of m */
466 #define QEMU_IS_ALIGNED(n, m) (((n) % (m)) == 0)
467
468 /* n-byte align pointer down */
469 #define QEMU_ALIGN_PTR_DOWN(p, n) \
470 ((typeof(p))QEMU_ALIGN_DOWN((uintptr_t)(p), (n)))
471
472 /* n-byte align pointer up */
473 #define QEMU_ALIGN_PTR_UP(p, n) \
474 ((typeof(p))QEMU_ALIGN_UP((uintptr_t)(p), (n)))
475
476 /* Check if pointer p is n-bytes aligned */
477 #define QEMU_PTR_IS_ALIGNED(p, n) QEMU_IS_ALIGNED((uintptr_t)(p), (n))
478
479 /*
480 * Round number down to multiple. Requires that d be a power of 2 (see
481 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
482 * numbers); works even if d is a smaller type than n.
483 */
484 #ifndef ROUND_DOWN
485 #define ROUND_DOWN(n, d) ((n) & -(0 ? (n) : (d)))
486 #endif
487
488 /*
489 * Round number up to multiple. Requires that d be a power of 2 (see
490 * QEMU_ALIGN_UP for a safer but slower version on arbitrary
491 * numbers); works even if d is a smaller type than n.
492 */
493 #ifndef ROUND_UP
494 #define ROUND_UP(n, d) ROUND_DOWN((n) + (d) - 1, (d))
495 #endif
496
497 #ifndef DIV_ROUND_UP
498 #define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
499 #endif
500
501 /*
502 * &(x)[0] is always a pointer - if it's same type as x then the argument is a
503 * pointer, not an array.
504 */
505 #define QEMU_IS_ARRAY(x) (!__builtin_types_compatible_p(typeof(x), \
506 typeof(&(x)[0])))
507 #ifndef ARRAY_SIZE
508 #define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])) + \
509 QEMU_BUILD_BUG_ON_ZERO(!QEMU_IS_ARRAY(x)))
510 #endif
511
512 int qemu_daemon(int nochdir, int noclose);
513 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared,
514 bool noreserve);
515 void qemu_anon_ram_free(void *ptr, size_t size);
516 int qemu_shm_alloc(size_t size, Error **errp);
517
518 #ifdef _WIN32
519 #define HAVE_CHARDEV_SERIAL 1
520 #define HAVE_CHARDEV_PARALLEL 1
521 #else
522 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
523 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
524 || defined(__GLIBC__) || defined(__APPLE__)
525 #define HAVE_CHARDEV_SERIAL 1
526 #endif
527 #if defined(__linux__) || defined(__FreeBSD__) \
528 || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
529 #define HAVE_CHARDEV_PARALLEL 1
530 #endif
531 #endif
532
533 #if defined(__HAIKU__)
534 #define SIGIO SIGPOLL
535 #endif
536
537 #ifdef HAVE_MADVISE_WITHOUT_PROTOTYPE
538 /*
539 * See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for discussion
540 * about Solaris missing the madvise() prototype.
541 */
542 int madvise(char *, size_t, int);
543 #endif
544
545 #if defined(CONFIG_LINUX)
546 #ifndef BUS_MCEERR_AR
547 #define BUS_MCEERR_AR 4
548 #endif
549 #ifndef BUS_MCEERR_AO
550 #define BUS_MCEERR_AO 5
551 #endif
552 #endif
553
554 #if defined(__linux__) && \
555 (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) \
556 || defined(__powerpc64__))
557 /* Use 2 MiB alignment so transparent hugepages can be used by KVM.
558 Valgrind does not support alignments larger than 1 MiB,
559 therefore we need special code which handles running on Valgrind. */
560 # define QEMU_VMALLOC_ALIGN (512 * 4096)
561 #elif defined(__linux__) && defined(__s390x__)
562 /* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
563 # define QEMU_VMALLOC_ALIGN (256 * 4096)
564 #elif defined(__linux__) && defined(__sparc__)
565 # define QEMU_VMALLOC_ALIGN MAX(qemu_real_host_page_size(), SHMLBA)
566 #elif defined(__linux__) && defined(__loongarch__)
567 /*
568 * For transparent hugepage optimization, it has better be huge page
569 * aligned. LoongArch host system supports two kinds of pagesize: 4K
570 * and 16K, here calculate huge page size from host page size
571 */
572 # define QEMU_VMALLOC_ALIGN (qemu_real_host_page_size() * \
573 qemu_real_host_page_size() / sizeof(long))
574 #else
575 # define QEMU_VMALLOC_ALIGN qemu_real_host_page_size()
576 #endif
577
578 #ifdef CONFIG_POSIX
579 struct qemu_signalfd_siginfo {
580 uint32_t ssi_signo; /* Signal number */
581 int32_t ssi_errno; /* Error number (unused) */
582 int32_t ssi_code; /* Signal code */
583 uint32_t ssi_pid; /* PID of sender */
584 uint32_t ssi_uid; /* Real UID of sender */
585 int32_t ssi_fd; /* File descriptor (SIGIO) */
586 uint32_t ssi_tid; /* Kernel timer ID (POSIX timers) */
587 uint32_t ssi_band; /* Band event (SIGIO) */
588 uint32_t ssi_overrun; /* POSIX timer overrun count */
589 uint32_t ssi_trapno; /* Trap number that caused signal */
590 int32_t ssi_status; /* Exit status or signal (SIGCHLD) */
591 int32_t ssi_int; /* Integer sent by sigqueue(2) */
592 uint64_t ssi_ptr; /* Pointer sent by sigqueue(2) */
593 uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */
594 uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */
595 uint64_t ssi_addr; /* Address that generated signal
596 (for hardware-generated signals) */
597 uint8_t pad[48]; /* Pad size to 128 bytes (allow for
598 additional fields in the future) */
599 };
600
601 int qemu_signalfd(const sigset_t *mask);
602 void sigaction_invoke(struct sigaction *action,
603 struct qemu_signalfd_siginfo *info);
604 #endif
605
606 /*
607 * Don't introduce new usage of this function, prefer the following
608 * qemu_open/qemu_create that take an "Error **errp"
609 */
610 int qemu_open_old(const char *name, int flags, ...);
611 int qemu_open(const char *name, int flags, Error **errp);
612 int qemu_create(const char *name, int flags, mode_t mode, Error **errp);
613 int qemu_close(int fd);
614 int qemu_unlink(const char *name);
615 #ifndef _WIN32
616 int qemu_dup_flags(int fd, int flags);
617 int qemu_dup(int fd);
618 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive);
619 int qemu_unlock_fd(int fd, int64_t start, int64_t len);
620 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive);
621 bool qemu_has_ofd_lock(void);
622 #endif
623
624 bool qemu_has_direct_io(void);
625
626 #if defined(__HAIKU__) && defined(__i386__)
627 #define FMT_pid "%ld"
628 #elif defined(WIN64)
629 #define FMT_pid "%" PRId64
630 #else
631 #define FMT_pid "%d"
632 #endif
633
634 bool qemu_write_pidfile(const char *pidfile, Error **errp);
635
636 int qemu_get_thread_id(void);
637
638 /**
639 * qemu_kill_thread:
640 * @tid: thread id.
641 * @sig: host signal.
642 *
643 * Send @sig to one of QEMU's own threads with identifier @tid.
644 */
645 int qemu_kill_thread(int tid, int sig);
646
647 #ifndef CONFIG_IOVEC
648 struct iovec {
649 void *iov_base;
650 size_t iov_len;
651 };
652 /*
653 * Use the same value as Linux for now.
654 */
655 #define IOV_MAX 1024
656
657 ssize_t readv(int fd, const struct iovec *iov, int iov_cnt);
658 ssize_t writev(int fd, const struct iovec *iov, int iov_cnt);
659 #endif
660
661 #ifdef _WIN32
qemu_timersub(const struct timeval * val1,const struct timeval * val2,struct timeval * res)662 static inline void qemu_timersub(const struct timeval *val1,
663 const struct timeval *val2,
664 struct timeval *res)
665 {
666 res->tv_sec = val1->tv_sec - val2->tv_sec;
667 if (val1->tv_usec < val2->tv_usec) {
668 res->tv_sec--;
669 res->tv_usec = val1->tv_usec - val2->tv_usec + 1000 * 1000;
670 } else {
671 res->tv_usec = val1->tv_usec - val2->tv_usec;
672 }
673 }
674 #else
675 #define qemu_timersub timersub
676 #endif
677
678 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
679 G_GNUC_WARN_UNUSED_RESULT;
680
681 void qemu_set_cloexec(int fd);
682
683 /* Return a dynamically allocated directory path that is appropriate for storing
684 * local state.
685 *
686 * The caller is responsible for releasing the value returned with g_free()
687 * after use.
688 */
689 char *qemu_get_local_state_dir(void);
690
691 /**
692 * qemu_getauxval:
693 * @type: the auxiliary vector key to lookup
694 *
695 * Search the auxiliary vector for @type, returning the value
696 * or 0 if @type is not present.
697 */
698 unsigned long qemu_getauxval(unsigned long type);
699
700 void qemu_set_tty_echo(int fd, bool echo);
701
702 typedef struct ThreadContext ThreadContext;
703
704 /**
705 * qemu_prealloc_mem:
706 * @fd: the fd mapped into the area, -1 for anonymous memory
707 * @area: start address of the are to preallocate
708 * @sz: the size of the area to preallocate
709 * @max_threads: maximum number of threads to use
710 * @tc: prealloc context threads pointer, NULL if not in use
711 * @async: request asynchronous preallocation, requires @tc
712 * @errp: returns an error if this function fails
713 *
714 * Preallocate memory (populate/prefault page tables writable) for the virtual
715 * memory area starting at @area with the size of @sz. After a successful call,
716 * each page in the area was faulted in writable at least once, for example,
717 * after allocating file blocks for mapped files.
718 *
719 * When setting @async, allocation might be performed asynchronously.
720 * qemu_finish_async_prealloc_mem() must be called to finish any asynchronous
721 * preallocation.
722 *
723 * Return: true on success, else false setting @errp with error.
724 */
725 bool qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads,
726 ThreadContext *tc, bool async, Error **errp);
727
728 /**
729 * qemu_finish_async_prealloc_mem:
730 * @errp: returns an error if this function fails
731 *
732 * Finish all outstanding asynchronous memory preallocation.
733 *
734 * Return: true on success, else false setting @errp with error.
735 */
736 bool qemu_finish_async_prealloc_mem(Error **errp);
737
738 /**
739 * qemu_get_pid_name:
740 * @pid: pid of a process
741 *
742 * For given @pid fetch its name. Caller is responsible for
743 * freeing the string when no longer needed.
744 * Returns allocated string on success, NULL on failure.
745 */
746 char *qemu_get_pid_name(pid_t pid);
747
748 /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even
749 * when intptr_t is 32-bit and we are aligning a long long.
750 */
qemu_real_host_page_size(void)751 static inline uintptr_t qemu_real_host_page_size(void)
752 {
753 return getpagesize();
754 }
755
qemu_real_host_page_mask(void)756 static inline intptr_t qemu_real_host_page_mask(void)
757 {
758 return -(intptr_t)qemu_real_host_page_size();
759 }
760
761 /*
762 * After using getopt or getopt_long, if you need to parse another set
763 * of options, then you must reset optind. Unfortunately the way to
764 * do this varies between implementations of getopt.
765 */
qemu_reset_optind(void)766 static inline void qemu_reset_optind(void)
767 {
768 #ifdef HAVE_OPTRESET
769 optind = 1;
770 optreset = 1;
771 #else
772 optind = 0;
773 #endif
774 }
775
776 int qemu_fdatasync(int fd);
777
778 /**
779 * qemu_close_all_open_fd:
780 *
781 * Close all open file descriptors except the ones supplied in the @skip array
782 *
783 * @skip: ordered array of distinct file descriptors that should not be closed
784 * if any, or NULL.
785 * @nskip: number of entries in the @skip array or 0 if @skip is NULL.
786 */
787 void qemu_close_all_open_fd(const int *skip, unsigned int nskip);
788
789 /**
790 * Sync changes made to the memory mapped file back to the backing
791 * storage. For POSIX compliant systems this will fallback
792 * to regular msync call. Otherwise it will trigger whole file sync
793 * (including the metadata case there is no support to skip that otherwise)
794 *
795 * @addr - start of the memory area to be synced
796 * @length - length of the are to be synced
797 * @fd - file descriptor for the file to be synced
798 * (mandatory only for POSIX non-compliant systems)
799 */
800 int qemu_msync(void *addr, size_t length, int fd);
801
802 /**
803 * qemu_get_host_physmem:
804 *
805 * Operating system agnostic way of querying host memory.
806 *
807 * Returns amount of physical memory on the system. This is purely
808 * advisery and may return 0 if we can't work it out. At the other
809 * end we saturate to SIZE_MAX if you are lucky enough to have that
810 * much memory.
811 */
812 size_t qemu_get_host_physmem(void);
813
814 /*
815 * Toggle write/execute on the pages marked MAP_JIT
816 * for the current thread.
817 */
818 #ifdef __APPLE__
qemu_thread_jit_execute(void)819 static inline void qemu_thread_jit_execute(void)
820 {
821 pthread_jit_write_protect_np(true);
822 }
823
qemu_thread_jit_write(void)824 static inline void qemu_thread_jit_write(void)
825 {
826 pthread_jit_write_protect_np(false);
827 }
828 #else
qemu_thread_jit_write(void)829 static inline void qemu_thread_jit_write(void) {}
qemu_thread_jit_execute(void)830 static inline void qemu_thread_jit_execute(void) {}
831 #endif
832
833 /**
834 * Platforms which do not support system() return ENOSYS
835 */
836 #ifndef HAVE_SYSTEM_FUNCTION
837 #define system platform_does_not_support_system
platform_does_not_support_system(const char * command)838 static inline int platform_does_not_support_system(const char *command)
839 {
840 errno = ENOSYS;
841 return -1;
842 }
843 #endif /* !HAVE_SYSTEM_FUNCTION */
844
845 #ifdef __cplusplus
846 }
847 #endif
848
849 #endif
850