qapi: add release designator to gluster logfile option
[qemu.git] / util / oslib-posix.c
blob67c65893a4fef130e9e2389fe4c6f79cd5b74aeb
1 /*
2 * os-posix-lib.c
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 * Copyright (c) 2010 Red Hat, Inc.
7 * QEMU library functions on POSIX which are shared between QEMU and
8 * the QEMU tools.
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26 * THE SOFTWARE.
29 #include "qemu/osdep.h"
30 #include <termios.h>
32 #include <glib/gprintf.h>
34 #include "sysemu/sysemu.h"
35 #include "trace.h"
36 #include "qapi/error.h"
37 #include "qemu/sockets.h"
38 #include <libgen.h>
39 #include <sys/signal.h>
40 #include "qemu/cutils.h"
42 #ifdef CONFIG_LINUX
43 #include <sys/syscall.h>
44 #endif
46 #ifdef __FreeBSD__
47 #include <sys/sysctl.h>
48 #include <libutil.h>
49 #endif
51 #include "qemu/mmap-alloc.h"
53 #ifdef CONFIG_DEBUG_STACK_USAGE
54 #include "qemu/error-report.h"
55 #endif
57 int qemu_get_thread_id(void)
59 #if defined(__linux__)
60 return syscall(SYS_gettid);
61 #else
62 return getpid();
63 #endif
66 int qemu_daemon(int nochdir, int noclose)
68 return daemon(nochdir, noclose);
71 void *qemu_oom_check(void *ptr)
73 if (ptr == NULL) {
74 fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
75 abort();
77 return ptr;
80 void *qemu_try_memalign(size_t alignment, size_t size)
82 void *ptr;
84 if (alignment < sizeof(void*)) {
85 alignment = sizeof(void*);
88 #if defined(_POSIX_C_SOURCE) && !defined(__sun__)
89 int ret;
90 ret = posix_memalign(&ptr, alignment, size);
91 if (ret != 0) {
92 errno = ret;
93 ptr = NULL;
95 #elif defined(CONFIG_BSD)
96 ptr = valloc(size);
97 #else
98 ptr = memalign(alignment, size);
99 #endif
100 trace_qemu_memalign(alignment, size, ptr);
101 return ptr;
104 void *qemu_memalign(size_t alignment, size_t size)
106 return qemu_oom_check(qemu_try_memalign(alignment, size));
109 /* alloc shared memory pages */
110 void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment)
112 size_t align = QEMU_VMALLOC_ALIGN;
113 void *ptr = qemu_ram_mmap(-1, size, align, false);
115 if (ptr == MAP_FAILED) {
116 return NULL;
119 if (alignment) {
120 *alignment = align;
123 trace_qemu_anon_ram_alloc(size, ptr);
124 return ptr;
127 void qemu_vfree(void *ptr)
129 trace_qemu_vfree(ptr);
130 free(ptr);
133 void qemu_anon_ram_free(void *ptr, size_t size)
135 trace_qemu_anon_ram_free(ptr, size);
136 qemu_ram_munmap(ptr, size);
139 void qemu_set_block(int fd)
141 int f;
142 f = fcntl(fd, F_GETFL);
143 fcntl(fd, F_SETFL, f & ~O_NONBLOCK);
146 void qemu_set_nonblock(int fd)
148 int f;
149 f = fcntl(fd, F_GETFL);
150 fcntl(fd, F_SETFL, f | O_NONBLOCK);
153 int socket_set_fast_reuse(int fd)
155 int val = 1, ret;
157 ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
158 (const char *)&val, sizeof(val));
160 assert(ret == 0);
162 return ret;
165 void qemu_set_cloexec(int fd)
167 int f;
168 f = fcntl(fd, F_GETFD);
169 fcntl(fd, F_SETFD, f | FD_CLOEXEC);
173 * Creates a pipe with FD_CLOEXEC set on both file descriptors
175 int qemu_pipe(int pipefd[2])
177 int ret;
179 #ifdef CONFIG_PIPE2
180 ret = pipe2(pipefd, O_CLOEXEC);
181 if (ret != -1 || errno != ENOSYS) {
182 return ret;
184 #endif
185 ret = pipe(pipefd);
186 if (ret == 0) {
187 qemu_set_cloexec(pipefd[0]);
188 qemu_set_cloexec(pipefd[1]);
191 return ret;
194 int qemu_utimens(const char *path, const struct timespec *times)
196 struct timeval tv[2], tv_now;
197 struct stat st;
198 int i;
199 #ifdef CONFIG_UTIMENSAT
200 int ret;
202 ret = utimensat(AT_FDCWD, path, times, AT_SYMLINK_NOFOLLOW);
203 if (ret != -1 || errno != ENOSYS) {
204 return ret;
206 #endif
207 /* Fallback: use utimes() instead of utimensat() */
209 /* happy if special cases */
210 if (times[0].tv_nsec == UTIME_OMIT && times[1].tv_nsec == UTIME_OMIT) {
211 return 0;
213 if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW) {
214 return utimes(path, NULL);
217 /* prepare for hard cases */
218 if (times[0].tv_nsec == UTIME_NOW || times[1].tv_nsec == UTIME_NOW) {
219 gettimeofday(&tv_now, NULL);
221 if (times[0].tv_nsec == UTIME_OMIT || times[1].tv_nsec == UTIME_OMIT) {
222 stat(path, &st);
225 for (i = 0; i < 2; i++) {
226 if (times[i].tv_nsec == UTIME_NOW) {
227 tv[i].tv_sec = tv_now.tv_sec;
228 tv[i].tv_usec = tv_now.tv_usec;
229 } else if (times[i].tv_nsec == UTIME_OMIT) {
230 tv[i].tv_sec = (i == 0) ? st.st_atime : st.st_mtime;
231 tv[i].tv_usec = 0;
232 } else {
233 tv[i].tv_sec = times[i].tv_sec;
234 tv[i].tv_usec = times[i].tv_nsec / 1000;
238 return utimes(path, &tv[0]);
241 char *
242 qemu_get_local_state_pathname(const char *relative_pathname)
244 return g_strdup_printf("%s/%s", CONFIG_QEMU_LOCALSTATEDIR,
245 relative_pathname);
248 void qemu_set_tty_echo(int fd, bool echo)
250 struct termios tty;
252 tcgetattr(fd, &tty);
254 if (echo) {
255 tty.c_lflag |= ECHO | ECHONL | ICANON | IEXTEN;
256 } else {
257 tty.c_lflag &= ~(ECHO | ECHONL | ICANON | IEXTEN);
260 tcsetattr(fd, TCSANOW, &tty);
263 static char exec_dir[PATH_MAX];
265 void qemu_init_exec_dir(const char *argv0)
267 char *dir;
268 char *p = NULL;
269 char buf[PATH_MAX];
271 assert(!exec_dir[0]);
273 #if defined(__linux__)
275 int len;
276 len = readlink("/proc/self/exe", buf, sizeof(buf) - 1);
277 if (len > 0) {
278 buf[len] = 0;
279 p = buf;
282 #elif defined(__FreeBSD__)
284 static int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
285 size_t len = sizeof(buf) - 1;
287 *buf = '\0';
288 if (!sysctl(mib, ARRAY_SIZE(mib), buf, &len, NULL, 0) &&
289 *buf) {
290 buf[sizeof(buf) - 1] = '\0';
291 p = buf;
294 #endif
295 /* If we don't have any way of figuring out the actual executable
296 location then try argv[0]. */
297 if (!p) {
298 if (!argv0) {
299 return;
301 p = realpath(argv0, buf);
302 if (!p) {
303 return;
306 dir = g_path_get_dirname(p);
308 pstrcpy(exec_dir, sizeof(exec_dir), dir);
310 g_free(dir);
313 char *qemu_get_exec_dir(void)
315 return g_strdup(exec_dir);
318 static sigjmp_buf sigjump;
320 static void sigbus_handler(int signal)
322 siglongjmp(sigjump, 1);
325 void os_mem_prealloc(int fd, char *area, size_t memory, Error **errp)
327 int ret;
328 struct sigaction act, oldact;
329 sigset_t set, oldset;
331 memset(&act, 0, sizeof(act));
332 act.sa_handler = &sigbus_handler;
333 act.sa_flags = 0;
335 ret = sigaction(SIGBUS, &act, &oldact);
336 if (ret) {
337 error_setg_errno(errp, errno,
338 "os_mem_prealloc: failed to install signal handler");
339 return;
342 /* unblock SIGBUS */
343 sigemptyset(&set);
344 sigaddset(&set, SIGBUS);
345 pthread_sigmask(SIG_UNBLOCK, &set, &oldset);
347 if (sigsetjmp(sigjump, 1)) {
348 error_setg(errp, "os_mem_prealloc: Insufficient free host memory "
349 "pages available to allocate guest RAM\n");
350 } else {
351 int i;
352 size_t hpagesize = qemu_fd_getpagesize(fd);
353 size_t numpages = DIV_ROUND_UP(memory, hpagesize);
355 /* MAP_POPULATE silently ignores failures */
356 for (i = 0; i < numpages; i++) {
357 memset(area + (hpagesize * i), 0, 1);
361 ret = sigaction(SIGBUS, &oldact, NULL);
362 if (ret) {
363 /* Terminate QEMU since it can't recover from error */
364 perror("os_mem_prealloc: failed to reinstall signal handler");
365 exit(1);
367 pthread_sigmask(SIG_SETMASK, &oldset, NULL);
371 static struct termios oldtty;
373 static void term_exit(void)
375 tcsetattr(0, TCSANOW, &oldtty);
378 static void term_init(void)
380 struct termios tty;
382 tcgetattr(0, &tty);
383 oldtty = tty;
385 tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP
386 |INLCR|IGNCR|ICRNL|IXON);
387 tty.c_oflag |= OPOST;
388 tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
389 tty.c_cflag &= ~(CSIZE|PARENB);
390 tty.c_cflag |= CS8;
391 tty.c_cc[VMIN] = 1;
392 tty.c_cc[VTIME] = 0;
394 tcsetattr(0, TCSANOW, &tty);
396 atexit(term_exit);
399 int qemu_read_password(char *buf, int buf_size)
401 uint8_t ch;
402 int i, ret;
404 printf("password: ");
405 fflush(stdout);
406 term_init();
407 i = 0;
408 for (;;) {
409 ret = read(0, &ch, 1);
410 if (ret == -1) {
411 if (errno == EAGAIN || errno == EINTR) {
412 continue;
413 } else {
414 break;
416 } else if (ret == 0) {
417 ret = -1;
418 break;
419 } else {
420 if (ch == '\r' ||
421 ch == '\n') {
422 ret = 0;
423 break;
425 if (i < (buf_size - 1)) {
426 buf[i++] = ch;
430 term_exit();
431 buf[i] = '\0';
432 printf("\n");
433 return ret;
437 char *qemu_get_pid_name(pid_t pid)
439 char *name = NULL;
441 #if defined(__FreeBSD__)
442 /* BSDs don't have /proc, but they provide a nice substitute */
443 struct kinfo_proc *proc = kinfo_getproc(pid);
445 if (proc) {
446 name = g_strdup(proc->ki_comm);
447 free(proc);
449 #else
450 /* Assume a system with reasonable procfs */
451 char *pid_path;
452 size_t len;
454 pid_path = g_strdup_printf("/proc/%d/cmdline", pid);
455 g_file_get_contents(pid_path, &name, &len, NULL);
456 g_free(pid_path);
457 #endif
459 return name;
463 pid_t qemu_fork(Error **errp)
465 sigset_t oldmask, newmask;
466 struct sigaction sig_action;
467 int saved_errno;
468 pid_t pid;
471 * Need to block signals now, so that child process can safely
472 * kill off caller's signal handlers without a race.
474 sigfillset(&newmask);
475 if (pthread_sigmask(SIG_SETMASK, &newmask, &oldmask) != 0) {
476 error_setg_errno(errp, errno,
477 "cannot block signals");
478 return -1;
481 pid = fork();
482 saved_errno = errno;
484 if (pid < 0) {
485 /* attempt to restore signal mask, but ignore failure, to
486 * avoid obscuring the fork failure */
487 (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
488 error_setg_errno(errp, saved_errno,
489 "cannot fork child process");
490 errno = saved_errno;
491 return -1;
492 } else if (pid) {
493 /* parent process */
495 /* Restore our original signal mask now that the child is
496 * safely running. Only documented failures are EFAULT (not
497 * possible, since we are using just-grabbed mask) or EINVAL
498 * (not possible, since we are using correct arguments). */
499 (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
500 } else {
501 /* child process */
502 size_t i;
504 /* Clear out all signal handlers from parent so nothing
505 * unexpected can happen in our child once we unblock
506 * signals */
507 sig_action.sa_handler = SIG_DFL;
508 sig_action.sa_flags = 0;
509 sigemptyset(&sig_action.sa_mask);
511 for (i = 1; i < NSIG; i++) {
512 /* Only possible errors are EFAULT or EINVAL The former
513 * won't happen, the latter we expect, so no need to check
514 * return value */
515 (void)sigaction(i, &sig_action, NULL);
518 /* Unmask all signals in child, since we've no idea what the
519 * caller's done with their signal mask and don't want to
520 * propagate that to children */
521 sigemptyset(&newmask);
522 if (pthread_sigmask(SIG_SETMASK, &newmask, NULL) != 0) {
523 Error *local_err = NULL;
524 error_setg_errno(&local_err, errno,
525 "cannot unblock signals");
526 error_report_err(local_err);
527 _exit(1);
530 return pid;
533 void *qemu_alloc_stack(size_t *sz)
535 void *ptr, *guardpage;
536 #ifdef CONFIG_DEBUG_STACK_USAGE
537 void *ptr2;
538 #endif
539 size_t pagesz = getpagesize();
540 #ifdef _SC_THREAD_STACK_MIN
541 /* avoid stacks smaller than _SC_THREAD_STACK_MIN */
542 long min_stack_sz = sysconf(_SC_THREAD_STACK_MIN);
543 *sz = MAX(MAX(min_stack_sz, 0), *sz);
544 #endif
545 /* adjust stack size to a multiple of the page size */
546 *sz = ROUND_UP(*sz, pagesz);
547 /* allocate one extra page for the guard page */
548 *sz += pagesz;
550 ptr = mmap(NULL, *sz, PROT_READ | PROT_WRITE,
551 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
552 if (ptr == MAP_FAILED) {
553 abort();
556 #if defined(HOST_IA64)
557 /* separate register stack */
558 guardpage = ptr + (((*sz - pagesz) / 2) & ~pagesz);
559 #elif defined(HOST_HPPA)
560 /* stack grows up */
561 guardpage = ptr + *sz - pagesz;
562 #else
563 /* stack grows down */
564 guardpage = ptr;
565 #endif
566 if (mprotect(guardpage, pagesz, PROT_NONE) != 0) {
567 abort();
570 #ifdef CONFIG_DEBUG_STACK_USAGE
571 for (ptr2 = ptr + pagesz; ptr2 < ptr + *sz; ptr2 += sizeof(uint32_t)) {
572 *(uint32_t *)ptr2 = 0xdeadbeaf;
574 #endif
576 return ptr;
579 #ifdef CONFIG_DEBUG_STACK_USAGE
580 static __thread unsigned int max_stack_usage;
581 #endif
583 void qemu_free_stack(void *stack, size_t sz)
585 #ifdef CONFIG_DEBUG_STACK_USAGE
586 unsigned int usage;
587 void *ptr;
589 for (ptr = stack + getpagesize(); ptr < stack + sz;
590 ptr += sizeof(uint32_t)) {
591 if (*(uint32_t *)ptr != 0xdeadbeaf) {
592 break;
595 usage = sz - (uintptr_t) (ptr - stack);
596 if (usage > max_stack_usage) {
597 error_report("thread %d max stack usage increased from %u to %u",
598 qemu_get_thread_id(), max_stack_usage, usage);
599 max_stack_usage = usage;
601 #endif
603 munmap(stack, sz);