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1 /***************************************************************************
2  *                                  _   _ ____  _
3  *  Project                     ___| | | |  _ \| |
4  *                             / __| | | | |_) | |
5  *                            | (__| |_| |  _ <| |___
6  *                             \___|\___/|_| \_\_____|
7  *
8  * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9  *
10  * This software is licensed as described in the file COPYING, which
11  * you should have received as part of this distribution. The terms
12  * are also available at https://curl.se/docs/copyright.html.
13  *
14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15  * copies of the Software, and permit persons to whom the Software is
16  * furnished to do so, under the terms of the COPYING file.
17  *
18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19  * KIND, either express or implied.
20  *
21  * SPDX-License-Identifier: curl
22  *
23  ***************************************************************************/
24 #include "server_setup.h"
25 
26 #include <signal.h>
27 #ifdef HAVE_NETINET_IN_H
28 #include <netinet/in.h>
29 #endif
30 #ifdef _XOPEN_SOURCE_EXTENDED
31 /* This define is "almost" required to build on HP-UX 11 */
32 #include <arpa/inet.h>
33 #endif
34 #ifdef HAVE_NETDB_H
35 #include <netdb.h>
36 #endif
37 #ifdef HAVE_POLL_H
38 #include <poll.h>
39 #elif defined(HAVE_SYS_POLL_H)
40 #include <sys/poll.h>
41 #endif
42 
43 #ifdef MSDOS
44 #include <dos.h>  /* delay() */
45 #endif
46 
47 #include "curlx.h" /* from the private lib dir */
48 #include "getpart.h"
49 #include "util.h"
50 #include "timeval.h"
51 
52 #ifdef USE_WINSOCK
53 #undef  EINTR
54 #define EINTR    4 /* errno.h value */
55 #undef  EINVAL
56 #define EINVAL  22 /* errno.h value */
57 #endif
58 
59 static struct timeval tvnow(void);
60 
61 /* This function returns a pointer to STATIC memory. It converts the given
62  * binary lump to a hex formatted string usable for output in logs or
63  * whatever.
64  */
data_to_hex(char * data,size_t len)65 char *data_to_hex(char *data, size_t len)
66 {
67   static char buf[256*3];
68   size_t i;
69   char *optr = buf;
70   char *iptr = data;
71 
72   if(len > 255)
73     len = 255;
74 
75   for(i = 0; i < len; i++) {
76     if((data[i] >= 0x20) && (data[i] < 0x7f))
77       *optr++ = *iptr++;
78     else {
79       msnprintf(optr, 4, "%%%02x", *iptr++);
80       optr += 3;
81     }
82   }
83   *optr = 0; /* in case no sprintf was used */
84 
85   return buf;
86 }
87 
logmsg(const char * msg,...)88 void logmsg(const char *msg, ...)
89 {
90   va_list ap;
91   char buffer[2048 + 1];
92   FILE *logfp;
93   struct timeval tv;
94   time_t sec;
95   struct tm *now;
96   char timebuf[20];
97   static time_t epoch_offset;
98   static int    known_offset;
99 
100   if(!serverlogfile) {
101     fprintf(stderr, "Error: serverlogfile not set\n");
102     return;
103   }
104 
105   tv = tvnow();
106   if(!known_offset) {
107     epoch_offset = time(NULL) - tv.tv_sec;
108     known_offset = 1;
109   }
110   sec = epoch_offset + tv.tv_sec;
111   /* !checksrc! disable BANNEDFUNC 1 */
112   now = localtime(&sec); /* not thread safe but we don't care */
113 
114   msnprintf(timebuf, sizeof(timebuf), "%02d:%02d:%02d.%06ld",
115             (int)now->tm_hour, (int)now->tm_min, (int)now->tm_sec,
116             (long)tv.tv_usec);
117 
118   va_start(ap, msg);
119   mvsnprintf(buffer, sizeof(buffer), msg, ap);
120   va_end(ap);
121 
122   do {
123     logfp = fopen(serverlogfile, "ab");
124   } while(!logfp && (errno == EINTR));
125   if(logfp) {
126     fprintf(logfp, "%s %s\n", timebuf, buffer);
127     fclose(logfp);
128   }
129   else {
130     int error = errno;
131     fprintf(stderr, "fopen() failed with error: %d %s\n",
132             error, strerror(error));
133     fprintf(stderr, "Error opening file: %s\n", serverlogfile);
134     fprintf(stderr, "Msg not logged: %s %s\n", timebuf, buffer);
135   }
136 }
137 
138 #ifdef _WIN32
139 /* use instead of strerror() on generic Windows */
win32_strerror(int err,char * buf,size_t buflen)140 static const char *win32_strerror(int err, char *buf, size_t buflen)
141 {
142   if(!FormatMessageA((FORMAT_MESSAGE_FROM_SYSTEM |
143                       FORMAT_MESSAGE_IGNORE_INSERTS), NULL, (DWORD)err,
144                      LANG_NEUTRAL, buf, (DWORD)buflen, NULL))
145     msnprintf(buf, buflen, "Unknown error %d (%#x)", err, err);
146   return buf;
147 }
148 
149 /* use instead of perror() on generic Windows */
win32_perror(const char * msg)150 void win32_perror(const char *msg)
151 {
152   char buf[512];
153   int err = SOCKERRNO;
154   win32_strerror(err, buf, sizeof(buf));
155   if(msg)
156     fprintf(stderr, "%s: ", msg);
157   fprintf(stderr, "%s\n", buf);
158 }
159 
win32_init(void)160 void win32_init(void)
161 {
162 #ifdef USE_WINSOCK
163   WORD wVersionRequested;
164   WSADATA wsaData;
165   int err;
166 
167   wVersionRequested = MAKEWORD(2, 2);
168   err = WSAStartup(wVersionRequested, &wsaData);
169 
170   if(err) {
171     perror("Winsock init failed");
172     logmsg("Error initialising Winsock -- aborting");
173     exit(1);
174   }
175 
176   if(LOBYTE(wsaData.wVersion) != LOBYTE(wVersionRequested) ||
177      HIBYTE(wsaData.wVersion) != HIBYTE(wVersionRequested) ) {
178     WSACleanup();
179     perror("Winsock init failed");
180     logmsg("No suitable winsock.dll found -- aborting");
181     exit(1);
182   }
183 #endif  /* USE_WINSOCK */
184 }
185 
win32_cleanup(void)186 void win32_cleanup(void)
187 {
188 #ifdef USE_WINSOCK
189   WSACleanup();
190 #endif  /* USE_WINSOCK */
191 
192   /* flush buffers of all streams regardless of their mode */
193   _flushall();
194 }
195 
196 /* socket-safe strerror (works on Winsock errors, too */
sstrerror(int err)197 const char *sstrerror(int err)
198 {
199   static char buf[512];
200   return win32_strerror(err, buf, sizeof(buf));
201 }
202 #endif  /* _WIN32 */
203 
204 /* set by the main code to point to where the test dir is */
205 const char *path = ".";
206 
test2fopen(long testno,const char * logdir)207 FILE *test2fopen(long testno, const char *logdir)
208 {
209   FILE *stream;
210   char filename[256];
211   /* first try the alternative, preprocessed, file */
212   msnprintf(filename, sizeof(filename), ALTTEST_DATA_PATH, logdir, testno);
213   stream = fopen(filename, "rb");
214   if(stream)
215     return stream;
216 
217   /* then try the source version */
218   msnprintf(filename, sizeof(filename), TEST_DATA_PATH, path, testno);
219   stream = fopen(filename, "rb");
220 
221   return stream;
222 }
223 
224 /*
225  * Portable function used for waiting a specific amount of ms.
226  * Waiting indefinitely with this function is not allowed, a
227  * zero or negative timeout value will return immediately.
228  *
229  * Return values:
230  *   -1 = system call error, or invalid timeout value
231  *    0 = specified timeout has elapsed
232  */
wait_ms(int timeout_ms)233 int wait_ms(int timeout_ms)
234 {
235 #if !defined(MSDOS) && !defined(USE_WINSOCK)
236 #ifndef HAVE_POLL
237   struct timeval pending_tv;
238 #endif
239   struct timeval initial_tv;
240   int pending_ms;
241 #endif
242   int r = 0;
243 
244   if(!timeout_ms)
245     return 0;
246   if(timeout_ms < 0) {
247     errno = EINVAL;
248     return -1;
249   }
250 #if defined(MSDOS)
251   delay(timeout_ms);
252 #elif defined(USE_WINSOCK)
253   Sleep((DWORD)timeout_ms);
254 #else
255   pending_ms = timeout_ms;
256   initial_tv = tvnow();
257   do {
258     int error;
259 #ifdef HAVE_POLL
260     r = poll(NULL, 0, pending_ms);
261 #else
262     pending_tv.tv_sec = pending_ms / 1000;
263     pending_tv.tv_usec = (pending_ms % 1000) * 1000;
264     r = select(0, NULL, NULL, NULL, &pending_tv);
265 #endif /* HAVE_POLL */
266     if(r != -1)
267       break;
268     error = errno;
269     if(error && (error != EINTR))
270       break;
271     pending_ms = timeout_ms - (int)timediff(tvnow(), initial_tv);
272     if(pending_ms <= 0)
273       break;
274   } while(r == -1);
275 #endif /* USE_WINSOCK */
276   if(r)
277     r = -1;
278   return r;
279 }
280 
our_getpid(void)281 curl_off_t our_getpid(void)
282 {
283   curl_off_t pid;
284 
285   pid = (curl_off_t)Curl_getpid();
286 #if defined(_WIN32)
287   /* store pid + 65536 to avoid conflict with Cygwin/msys PIDs, see also:
288    * - https://cygwin.com/git/?p=newlib-cygwin.git;a=commit;289    *   h=b5e1003722cb14235c4f166be72c09acdffc62ea
290    * - https://cygwin.com/git/?p=newlib-cygwin.git;a=commit;291    *   h=448cf5aa4b429d5a9cebf92a0da4ab4b5b6d23fe
292    */
293   pid += 65536;
294 #endif
295   return pid;
296 }
297 
write_pidfile(const char * filename)298 int write_pidfile(const char *filename)
299 {
300   FILE *pidfile;
301   curl_off_t pid;
302 
303   pid = our_getpid();
304   pidfile = fopen(filename, "wb");
305   if(!pidfile) {
306     logmsg("Couldn't write pid file: %s %s", filename, strerror(errno));
307     return 0; /* fail */
308   }
309   fprintf(pidfile, "%" CURL_FORMAT_CURL_OFF_T "\n", pid);
310   fclose(pidfile);
311   logmsg("Wrote pid %" CURL_FORMAT_CURL_OFF_T " to %s", pid, filename);
312   return 1; /* success */
313 }
314 
315 /* store the used port number in a file */
write_portfile(const char * filename,int port)316 int write_portfile(const char *filename, int port)
317 {
318   FILE *portfile = fopen(filename, "wb");
319   if(!portfile) {
320     logmsg("Couldn't write port file: %s %s", filename, strerror(errno));
321     return 0; /* fail */
322   }
323   fprintf(portfile, "%d\n", port);
324   fclose(portfile);
325   logmsg("Wrote port %d to %s", port, filename);
326   return 1; /* success */
327 }
328 
set_advisor_read_lock(const char * filename)329 void set_advisor_read_lock(const char *filename)
330 {
331   FILE *lockfile;
332   int error = 0;
333   int res;
334 
335   do {
336     lockfile = fopen(filename, "wb");
337   } while(!lockfile && ((error = errno) == EINTR));
338   if(!lockfile) {
339     logmsg("Error creating lock file %s error: %d %s",
340            filename, error, strerror(error));
341     return;
342   }
343 
344   res = fclose(lockfile);
345   if(res)
346     logmsg("Error closing lock file %s error: %d %s",
347            filename, errno, strerror(errno));
348 }
349 
clear_advisor_read_lock(const char * filename)350 void clear_advisor_read_lock(const char *filename)
351 {
352   int error = 0;
353   int res;
354 
355   /*
356   ** Log all removal failures. Even those due to file not existing.
357   ** This allows to detect if unexpectedly the file has already been
358   ** removed by a process different than the one that should do this.
359   */
360 
361   do {
362     res = unlink(filename);
363   } while(res && ((error = errno) == EINTR));
364   if(res)
365     logmsg("Error removing lock file %s error: %d %s",
366            filename, error, strerror(error));
367 }
368 
369 
370 #if defined(_WIN32)
371 
tvnow(void)372 static struct timeval tvnow(void)
373 {
374   /*
375   ** GetTickCount() is available on _all_ Windows versions from W95 up
376   ** to nowadays. Returns milliseconds elapsed since last system boot,
377   ** increases monotonically and wraps once 49.7 days have elapsed.
378   **
379   ** GetTickCount64() is available on Windows version from Windows Vista
380   ** and Windows Server 2008 up to nowadays. The resolution of the
381   ** function is limited to the resolution of the system timer, which
382   ** is typically in the range of 10 milliseconds to 16 milliseconds.
383   */
384   struct timeval now;
385 #if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0600)
386   ULONGLONG milliseconds = GetTickCount64();
387 #else
388   DWORD milliseconds = GetTickCount();
389 #endif
390   now.tv_sec = (long)(milliseconds / 1000);
391   now.tv_usec = (long)((milliseconds % 1000) * 1000);
392   return now;
393 }
394 
395 #elif defined(HAVE_CLOCK_GETTIME_MONOTONIC)
396 
tvnow(void)397 static struct timeval tvnow(void)
398 {
399   /*
400   ** clock_gettime() is granted to be increased monotonically when the
401   ** monotonic clock is queried. Time starting point is unspecified, it
402   ** could be the system start-up time, the Epoch, or something else,
403   ** in any case the time starting point does not change once that the
404   ** system has started up.
405   */
406   struct timeval now;
407   struct timespec tsnow;
408   if(0 == clock_gettime(CLOCK_MONOTONIC, &tsnow)) {
409     now.tv_sec = tsnow.tv_sec;
410     now.tv_usec = (int)(tsnow.tv_nsec / 1000);
411   }
412   /*
413   ** Even when the configure process has truly detected monotonic clock
414   ** availability, it might happen that it is not actually available at
415   ** run-time. When this occurs simply fallback to other time source.
416   */
417 #ifdef HAVE_GETTIMEOFDAY
418   else
419     (void)gettimeofday(&now, NULL);
420 #else
421   else {
422     now.tv_sec = time(NULL);
423     now.tv_usec = 0;
424   }
425 #endif
426   return now;
427 }
428 
429 #elif defined(HAVE_GETTIMEOFDAY)
430 
tvnow(void)431 static struct timeval tvnow(void)
432 {
433   /*
434   ** gettimeofday() is not granted to be increased monotonically, due to
435   ** clock drifting and external source time synchronization it can jump
436   ** forward or backward in time.
437   */
438   struct timeval now;
439   (void)gettimeofday(&now, NULL);
440   return now;
441 }
442 
443 #else
444 
tvnow(void)445 static struct timeval tvnow(void)
446 {
447   /*
448   ** time() returns the value of time in seconds since the Epoch.
449   */
450   struct timeval now;
451   now.tv_sec = time(NULL);
452   now.tv_usec = 0;
453   return now;
454 }
455 
456 #endif
457 
timediff(struct timeval newer,struct timeval older)458 long timediff(struct timeval newer, struct timeval older)
459 {
460   timediff_t diff = newer.tv_sec-older.tv_sec;
461   if(diff >= (LONG_MAX/1000))
462     return LONG_MAX;
463   else if(diff <= (LONG_MIN/1000))
464     return LONG_MIN;
465   return (long)(newer.tv_sec-older.tv_sec)*1000+
466     (long)(newer.tv_usec-older.tv_usec)/1000;
467 }
468 
469 /* vars used to keep around previous signal handlers */
470 
471 typedef void (*SIGHANDLER_T)(int);
472 
473 #if defined(_MSC_VER) && (_MSC_VER <= 1700)
474 /* Workaround for warning C4306:
475    'type cast' : conversion from 'int' to 'void (__cdecl *)(int)' */
476 #undef SIG_ERR
477 #define SIG_ERR  ((SIGHANDLER_T)(size_t)-1)
478 #endif
479 
480 #ifdef SIGHUP
481 static SIGHANDLER_T old_sighup_handler  = SIG_ERR;
482 #endif
483 
484 #ifdef SIGPIPE
485 static SIGHANDLER_T old_sigpipe_handler = SIG_ERR;
486 #endif
487 
488 #ifdef SIGALRM
489 static SIGHANDLER_T old_sigalrm_handler = SIG_ERR;
490 #endif
491 
492 #ifdef SIGINT
493 static SIGHANDLER_T old_sigint_handler  = SIG_ERR;
494 #endif
495 
496 #ifdef SIGTERM
497 static SIGHANDLER_T old_sigterm_handler = SIG_ERR;
498 #endif
499 
500 #if defined(SIGBREAK) && defined(_WIN32)
501 static SIGHANDLER_T old_sigbreak_handler = SIG_ERR;
502 #endif
503 
504 #if defined(_WIN32) && !defined(CURL_WINDOWS_UWP)
505 #ifdef _WIN32_WCE
506 static DWORD thread_main_id = 0;
507 #else
508 static unsigned int thread_main_id = 0;
509 #endif
510 static HANDLE thread_main_window = NULL;
511 static HWND hidden_main_window = NULL;
512 #endif
513 
514 /* var which if set indicates that the program should finish execution */
515 volatile int got_exit_signal = 0;
516 
517 /* if next is set indicates the first signal handled in exit_signal_handler */
518 volatile int exit_signal = 0;
519 
520 #ifdef _WIN32
521 /* event which if set indicates that the program should finish */
522 HANDLE exit_event = NULL;
523 #endif
524 
525 /* signal handler that will be triggered to indicate that the program
526  * should finish its execution in a controlled manner as soon as possible.
527  * The first time this is called it will set got_exit_signal to one and
528  * store in exit_signal the signal that triggered its execution.
529  */
exit_signal_handler(int signum)530 static void exit_signal_handler(int signum)
531 {
532   int old_errno = errno;
533   logmsg("exit_signal_handler: %d", signum);
534   if(got_exit_signal == 0) {
535     got_exit_signal = 1;
536     exit_signal = signum;
537 #ifdef _WIN32
538     if(exit_event)
539       (void)SetEvent(exit_event);
540 #endif
541   }
542   (void)signal(signum, exit_signal_handler);
543   errno = old_errno;
544 }
545 
546 #ifdef _WIN32
547 /* CTRL event handler for Windows Console applications to simulate
548  * SIGINT, SIGTERM and SIGBREAK on CTRL events and trigger signal handler.
549  *
550  * Background information from MSDN:
551  * SIGINT is not supported for any Win32 application. When a CTRL+C
552  * interrupt occurs, Win32 operating systems generate a new thread
553  * to specifically handle that interrupt. This can cause a single-thread
554  * application, such as one in UNIX, to become multithreaded and cause
555  * unexpected behavior.
556  * [...]
557  * The SIGILL and SIGTERM signals are not generated under Windows.
558  * They are included for ANSI compatibility. Therefore, you can set
559  * signal handlers for these signals by using signal, and you can also
560  * explicitly generate these signals by calling raise. Source:
561  * https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/signal
562  */
ctrl_event_handler(DWORD dwCtrlType)563 static BOOL WINAPI ctrl_event_handler(DWORD dwCtrlType)
564 {
565   int signum = 0;
566   logmsg("ctrl_event_handler: %lu", dwCtrlType);
567   switch(dwCtrlType) {
568 #ifdef SIGINT
569   case CTRL_C_EVENT:
570     signum = SIGINT;
571     break;
572 #endif
573 #ifdef SIGTERM
574   case CTRL_CLOSE_EVENT:
575     signum = SIGTERM;
576     break;
577 #endif
578 #ifdef SIGBREAK
579   case CTRL_BREAK_EVENT:
580     signum = SIGBREAK;
581     break;
582 #endif
583   default:
584     return FALSE;
585   }
586   if(signum) {
587     logmsg("ctrl_event_handler: %lu -> %d", dwCtrlType, signum);
588     raise(signum);
589   }
590   return TRUE;
591 }
592 #endif
593 
594 #if defined(_WIN32) && !defined(CURL_WINDOWS_UWP)
595 /* Window message handler for Windows applications to add support
596  * for graceful process termination via taskkill (without /f) which
597  * sends WM_CLOSE to all Windows of a process (even hidden ones).
598  *
599  * Therefore we create and run a hidden Window in a separate thread
600  * to receive and handle the WM_CLOSE message as SIGTERM signal.
601  */
main_window_proc(HWND hwnd,UINT uMsg,WPARAM wParam,LPARAM lParam)602 static LRESULT CALLBACK main_window_proc(HWND hwnd, UINT uMsg,
603                                          WPARAM wParam, LPARAM lParam)
604 {
605   int signum = 0;
606   if(hwnd == hidden_main_window) {
607     switch(uMsg) {
608 #ifdef SIGTERM
609       case WM_CLOSE:
610         signum = SIGTERM;
611         break;
612 #endif
613     case WM_DESTROY:
614       PostQuitMessage(0);
615       break;
616     }
617     if(signum) {
618       logmsg("main_window_proc: %d -> %d", uMsg, signum);
619       raise(signum);
620     }
621   }
622   return DefWindowProc(hwnd, uMsg, wParam, lParam);
623 }
624 /* Window message queue loop for hidden main window, details see above.
625  */
626 #ifdef _WIN32_WCE
main_window_loop(LPVOID lpParameter)627 static DWORD WINAPI main_window_loop(LPVOID lpParameter)
628 #else
629 #include <process.h>
630 static unsigned int WINAPI main_window_loop(void *lpParameter)
631 #endif
632 {
633   WNDCLASS wc;
634   BOOL ret;
635   MSG msg;
636 
637   ZeroMemory(&wc, sizeof(wc));
638   wc.lpfnWndProc = (WNDPROC)main_window_proc;
639   wc.hInstance = (HINSTANCE)lpParameter;
640   wc.lpszClassName = TEXT("MainWClass");
641   if(!RegisterClass(&wc)) {
642     perror("RegisterClass failed");
643     return (DWORD)-1;
644   }
645 
646   hidden_main_window = CreateWindowEx(0, TEXT("MainWClass"),
647                                       TEXT("Recv WM_CLOSE msg"),
648                                       WS_OVERLAPPEDWINDOW,
649                                       CW_USEDEFAULT, CW_USEDEFAULT,
650                                       CW_USEDEFAULT, CW_USEDEFAULT,
651                                       (HWND)NULL, (HMENU)NULL,
652                                       wc.hInstance, (LPVOID)NULL);
653   if(!hidden_main_window) {
654     perror("CreateWindowEx failed");
655     return (DWORD)-1;
656   }
657 
658   do {
659     ret = GetMessage(&msg, NULL, 0, 0);
660     if(ret == -1) {
661       perror("GetMessage failed");
662       return (DWORD)-1;
663     }
664     else if(ret) {
665       if(msg.message == WM_APP) {
666         DestroyWindow(hidden_main_window);
667       }
668       else if(msg.hwnd && !TranslateMessage(&msg)) {
669         DispatchMessage(&msg);
670       }
671     }
672   } while(ret);
673 
674   hidden_main_window = NULL;
675   return (DWORD)msg.wParam;
676 }
677 #endif
678 
set_signal(int signum,SIGHANDLER_T handler,bool restartable)679 static SIGHANDLER_T set_signal(int signum, SIGHANDLER_T handler,
680                                bool restartable)
681 {
682 #if defined(HAVE_SIGACTION) && defined(SA_RESTART)
683   struct sigaction sa, oldsa;
684 
685   memset(&sa, 0, sizeof(sa));
686   sa.sa_handler = handler;
687   sigemptyset(&sa.sa_mask);
688   sigaddset(&sa.sa_mask, signum);
689   sa.sa_flags = restartable ? SA_RESTART : 0;
690 
691   if(sigaction(signum, &sa, &oldsa))
692     return SIG_ERR;
693 
694   return oldsa.sa_handler;
695 #else
696   SIGHANDLER_T oldhdlr = signal(signum, handler);
697 
698 #ifdef HAVE_SIGINTERRUPT
699   if(oldhdlr != SIG_ERR)
700     siginterrupt(signum, (int) restartable);
701 #else
702   (void) restartable;
703 #endif
704 
705   return oldhdlr;
706 #endif
707 }
708 
install_signal_handlers(bool keep_sigalrm)709 void install_signal_handlers(bool keep_sigalrm)
710 {
711 #ifdef _WIN32
712   /* setup Windows exit event before any signal can trigger */
713   exit_event = CreateEvent(NULL, TRUE, FALSE, NULL);
714   if(!exit_event)
715     logmsg("cannot create exit event");
716 #endif
717 #ifdef SIGHUP
718   /* ignore SIGHUP signal */
719   old_sighup_handler = set_signal(SIGHUP, SIG_IGN, FALSE);
720   if(old_sighup_handler == SIG_ERR)
721     logmsg("cannot install SIGHUP handler: %s", strerror(errno));
722 #endif
723 #ifdef SIGPIPE
724   /* ignore SIGPIPE signal */
725   old_sigpipe_handler = set_signal(SIGPIPE, SIG_IGN, FALSE);
726   if(old_sigpipe_handler == SIG_ERR)
727     logmsg("cannot install SIGPIPE handler: %s", strerror(errno));
728 #endif
729 #ifdef SIGALRM
730   if(!keep_sigalrm) {
731     /* ignore SIGALRM signal */
732     old_sigalrm_handler = set_signal(SIGALRM, SIG_IGN, FALSE);
733     if(old_sigalrm_handler == SIG_ERR)
734       logmsg("cannot install SIGALRM handler: %s", strerror(errno));
735   }
736 #else
737   (void)keep_sigalrm;
738 #endif
739 #ifdef SIGINT
740   /* handle SIGINT signal with our exit_signal_handler */
741   old_sigint_handler = set_signal(SIGINT, exit_signal_handler, TRUE);
742   if(old_sigint_handler == SIG_ERR)
743     logmsg("cannot install SIGINT handler: %s", strerror(errno));
744 #endif
745 #ifdef SIGTERM
746   /* handle SIGTERM signal with our exit_signal_handler */
747   old_sigterm_handler = set_signal(SIGTERM, exit_signal_handler, TRUE);
748   if(old_sigterm_handler == SIG_ERR)
749     logmsg("cannot install SIGTERM handler: %s", strerror(errno));
750 #endif
751 #if defined(SIGBREAK) && defined(_WIN32)
752   /* handle SIGBREAK signal with our exit_signal_handler */
753   old_sigbreak_handler = set_signal(SIGBREAK, exit_signal_handler, TRUE);
754   if(old_sigbreak_handler == SIG_ERR)
755     logmsg("cannot install SIGBREAK handler: %s", strerror(errno));
756 #endif
757 #ifdef _WIN32
758   if(!SetConsoleCtrlHandler(ctrl_event_handler, TRUE))
759     logmsg("cannot install CTRL event handler");
760 
761 #ifndef CURL_WINDOWS_UWP
762   {
763 #ifdef _WIN32_WCE
764     typedef HANDLE curl_win_thread_handle_t;
765 #else
766     typedef uintptr_t curl_win_thread_handle_t;
767 #endif
768     curl_win_thread_handle_t thread;
769 #ifdef _WIN32_WCE
770     thread = CreateThread(NULL, 0, &main_window_loop,
771                           (LPVOID)GetModuleHandle(NULL), 0, &thread_main_id);
772 #else
773     thread = _beginthreadex(NULL, 0, &main_window_loop,
774                             (void *)GetModuleHandle(NULL), 0, &thread_main_id);
775 #endif
776     thread_main_window = (HANDLE)thread;
777     if(!thread_main_window || !thread_main_id)
778       logmsg("cannot start main window loop");
779   }
780 #endif
781 #endif
782 }
783 
restore_signal_handlers(bool keep_sigalrm)784 void restore_signal_handlers(bool keep_sigalrm)
785 {
786 #ifdef SIGHUP
787   if(SIG_ERR != old_sighup_handler)
788     (void) set_signal(SIGHUP, old_sighup_handler, FALSE);
789 #endif
790 #ifdef SIGPIPE
791   if(SIG_ERR != old_sigpipe_handler)
792     (void) set_signal(SIGPIPE, old_sigpipe_handler, FALSE);
793 #endif
794 #ifdef SIGALRM
795   if(!keep_sigalrm) {
796     if(SIG_ERR != old_sigalrm_handler)
797       (void) set_signal(SIGALRM, old_sigalrm_handler, FALSE);
798   }
799 #else
800   (void)keep_sigalrm;
801 #endif
802 #ifdef SIGINT
803   if(SIG_ERR != old_sigint_handler)
804     (void) set_signal(SIGINT, old_sigint_handler, FALSE);
805 #endif
806 #ifdef SIGTERM
807   if(SIG_ERR != old_sigterm_handler)
808     (void) set_signal(SIGTERM, old_sigterm_handler, FALSE);
809 #endif
810 #if defined(SIGBREAK) && defined(_WIN32)
811   if(SIG_ERR != old_sigbreak_handler)
812     (void) set_signal(SIGBREAK, old_sigbreak_handler, FALSE);
813 #endif
814 #ifdef _WIN32
815   (void)SetConsoleCtrlHandler(ctrl_event_handler, FALSE);
816 #ifndef CURL_WINDOWS_UWP
817   if(thread_main_window && thread_main_id) {
818     if(PostThreadMessage(thread_main_id, WM_APP, 0, 0)) {
819       if(WaitForSingleObjectEx(thread_main_window, INFINITE, TRUE)) {
820         if(CloseHandle(thread_main_window)) {
821           thread_main_window = NULL;
822           thread_main_id = 0;
823         }
824       }
825     }
826   }
827   if(exit_event) {
828     if(CloseHandle(exit_event)) {
829       exit_event = NULL;
830     }
831   }
832 #endif
833 #endif
834 }
835 
836 #ifdef USE_UNIX_SOCKETS
837 
bind_unix_socket(curl_socket_t sock,const char * unix_socket,struct sockaddr_un * sau)838 int bind_unix_socket(curl_socket_t sock, const char *unix_socket,
839                      struct sockaddr_un *sau)
840 {
841   int error;
842   int rc;
843   size_t len = strlen(unix_socket);
844 
845   memset(sau, 0, sizeof(struct sockaddr_un));
846   sau->sun_family = AF_UNIX;
847   if(len >= sizeof(sau->sun_path) - 1) {
848     logmsg("Too long unix socket domain path (%zd)", len);
849     return -1;
850   }
851   strcpy(sau->sun_path, unix_socket);
852   rc = bind(sock, (struct sockaddr*)sau, sizeof(struct sockaddr_un));
853   if(0 != rc && SOCKERRNO == EADDRINUSE) {
854     struct_stat statbuf;
855     /* socket already exists. Perhaps it is stale? */
856     curl_socket_t unixfd = socket(AF_UNIX, SOCK_STREAM, 0);
857     if(CURL_SOCKET_BAD == unixfd) {
858       logmsg("Failed to create socket at %s: (%d) %s",
859              unix_socket, SOCKERRNO, sstrerror(SOCKERRNO));
860       return -1;
861     }
862     /* check whether the server is alive */
863     rc = connect(unixfd, (struct sockaddr*)sau, sizeof(struct sockaddr_un));
864     error = SOCKERRNO;
865     sclose(unixfd);
866     if(0 != rc && ECONNREFUSED != error) {
867       logmsg("Failed to connect to %s: (%d) %s",
868              unix_socket, error, sstrerror(error));
869       return rc;
870     }
871     /* socket server is not alive, now check if it was actually a socket. */
872 #ifdef _WIN32
873     /* Windows does not have lstat function. */
874     rc = curlx_win32_stat(unix_socket, &statbuf);
875 #else
876     rc = lstat(unix_socket, &statbuf);
877 #endif
878     if(0 != rc) {
879       logmsg("Error binding socket, failed to stat %s: (%d) %s",
880              unix_socket, errno, strerror(errno));
881       return rc;
882     }
883 #ifdef S_IFSOCK
884     if((statbuf.st_mode & S_IFSOCK) != S_IFSOCK) {
885       logmsg("Error binding socket, failed to stat %s", unix_socket);
886       return -1;
887     }
888 #endif
889     /* dead socket, cleanup and retry bind */
890     rc = unlink(unix_socket);
891     if(0 != rc) {
892       logmsg("Error binding socket, failed to unlink %s: (%d) %s",
893              unix_socket, errno, strerror(errno));
894       return rc;
895     }
896     /* stale socket is gone, retry bind */
897     rc = bind(sock, (struct sockaddr*)sau, sizeof(struct sockaddr_un));
898   }
899   return rc;
900 }
901 #endif
902