1 /*
2 Minetest
3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
4 
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
9 
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 GNU Lesser General Public License for more details.
14 
15 You should have received a copy of the GNU Lesser General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19 
20 /*
21 	Random portability stuff
22 
23 	See comments in porting.h
24 */
25 
26 #include "porting.h"
27 
28 #if defined(__FreeBSD__)  || defined(__NetBSD__) || defined(__DragonFly__) || defined(__OpenBSD__)
29 	#include <sys/types.h>
30 	#include <sys/sysctl.h>
31 	extern char **environ;
32 #elif defined(_WIN32)
33 	#include <windows.h>
34 	#include <wincrypt.h>
35 	#include <algorithm>
36 	#include <shlwapi.h>
37 	#include <shellapi.h>
38 #endif
39 #if !defined(_WIN32)
40 	#include <unistd.h>
41 	#include <sys/utsname.h>
42 	#if !defined(__ANDROID__)
43 		#include <spawn.h>
44 	#endif
45 #endif
46 #if defined(__hpux)
47 	#define _PSTAT64
48 	#include <sys/pstat.h>
49 #endif
50 #if defined(__ANDROID__)
51 	#include "porting_android.h"
52 #endif
53 #if defined(__APPLE__)
54 	// For _NSGetEnviron()
55 	// Related: https://gitlab.haskell.org/ghc/ghc/issues/2458
56 	#include <crt_externs.h>
57 #endif
58 
59 #if defined(__HAIKU__)
60         #include <FindDirectory.h>
61 #endif
62 
63 #include "config.h"
64 #include "debug.h"
65 #include "filesys.h"
66 #include "log.h"
67 #include "util/string.h"
68 #include <list>
69 #include <cstdarg>
70 #include <cstdio>
71 
72 namespace porting
73 {
74 
75 /*
76 	Signal handler (grabs Ctrl-C on POSIX systems)
77 */
78 
79 bool g_killed = false;
80 
signal_handler_killstatus()81 bool *signal_handler_killstatus()
82 {
83 	return &g_killed;
84 }
85 
86 #if !defined(_WIN32) // POSIX
87 	#include <signal.h>
88 
signal_handler(int sig)89 void signal_handler(int sig)
90 {
91 	if (!g_killed) {
92 		if (sig == SIGINT) {
93 			dstream << "INFO: signal_handler(): "
94 				<< "Ctrl-C pressed, shutting down." << std::endl;
95 		} else if (sig == SIGTERM) {
96 			dstream << "INFO: signal_handler(): "
97 				<< "got SIGTERM, shutting down." << std::endl;
98 		}
99 
100 		// Comment out for less clutter when testing scripts
101 		/*dstream << "INFO: sigint_handler(): "
102 				<< "Printing debug stacks" << std::endl;
103 		debug_stacks_print();*/
104 
105 		g_killed = true;
106 	} else {
107 		(void)signal(sig, SIG_DFL);
108 	}
109 }
110 
signal_handler_init(void)111 void signal_handler_init(void)
112 {
113 	(void)signal(SIGINT, signal_handler);
114 	(void)signal(SIGTERM, signal_handler);
115 }
116 
117 #else // _WIN32
118 	#include <signal.h>
119 
event_handler(DWORD sig)120 BOOL WINAPI event_handler(DWORD sig)
121 {
122 	switch (sig) {
123 	case CTRL_C_EVENT:
124 	case CTRL_CLOSE_EVENT:
125 	case CTRL_LOGOFF_EVENT:
126 	case CTRL_SHUTDOWN_EVENT:
127 		if (!g_killed) {
128 			dstream << "INFO: event_handler(): "
129 				<< "Ctrl+C, Close Event, Logoff Event or Shutdown Event,"
130 				" shutting down." << std::endl;
131 			g_killed = true;
132 		} else {
133 			(void)signal(SIGINT, SIG_DFL);
134 		}
135 		break;
136 	case CTRL_BREAK_EVENT:
137 		break;
138 	}
139 
140 	return TRUE;
141 }
142 
signal_handler_init(void)143 void signal_handler_init(void)
144 {
145 	SetConsoleCtrlHandler((PHANDLER_ROUTINE)event_handler, TRUE);
146 }
147 
148 #endif
149 
150 
151 /*
152 	Path mangler
153 */
154 
155 // Default to RUN_IN_PLACE style relative paths
156 std::string path_share = "..";
157 std::string path_user = "..";
158 std::string path_locale = path_share + DIR_DELIM + "locale";
159 std::string path_cache = path_user + DIR_DELIM + "cache";
160 
161 
getDataPath(const char * subpath)162 std::string getDataPath(const char *subpath)
163 {
164 	return path_share + DIR_DELIM + subpath;
165 }
166 
pathRemoveFile(char * path,char delim)167 void pathRemoveFile(char *path, char delim)
168 {
169 	// Remove filename and path delimiter
170 	int i;
171 	for(i = strlen(path)-1; i>=0; i--)
172 	{
173 		if(path[i] == delim)
174 			break;
175 	}
176 	path[i] = 0;
177 }
178 
detectMSVCBuildDir(const std::string & path)179 bool detectMSVCBuildDir(const std::string &path)
180 {
181 	const char *ends[] = {
182 		"bin\\Release",
183 		"bin\\MinSizeRel",
184 		"bin\\RelWithDebInfo",
185 		"bin\\Debug",
186 		"bin\\Build",
187 		NULL
188 	};
189 	return (!removeStringEnd(path, ends).empty());
190 }
191 
get_sysinfo()192 std::string get_sysinfo()
193 {
194 #ifdef _WIN32
195 
196 	std::ostringstream oss;
197 	LPSTR filePath = new char[MAX_PATH];
198 	UINT blockSize;
199 	VS_FIXEDFILEINFO *fixedFileInfo;
200 
201 	GetSystemDirectoryA(filePath, MAX_PATH);
202 	PathAppendA(filePath, "kernel32.dll");
203 
204 	DWORD dwVersionSize = GetFileVersionInfoSizeA(filePath, NULL);
205 	LPBYTE lpVersionInfo = new BYTE[dwVersionSize];
206 
207 	GetFileVersionInfoA(filePath, 0, dwVersionSize, lpVersionInfo);
208 	VerQueryValueA(lpVersionInfo, "\\", (LPVOID *)&fixedFileInfo, &blockSize);
209 
210 	oss << "Windows/"
211 		<< HIWORD(fixedFileInfo->dwProductVersionMS) << '.' // Major
212 		<< LOWORD(fixedFileInfo->dwProductVersionMS) << '.' // Minor
213 		<< HIWORD(fixedFileInfo->dwProductVersionLS) << ' '; // Build
214 
215 	#ifdef _WIN64
216 	oss << "x86_64";
217 	#else
218 	BOOL is64 = FALSE;
219 	if (IsWow64Process(GetCurrentProcess(), &is64) && is64)
220 		oss << "x86_64"; // 32-bit app on 64-bit OS
221 	else
222 		oss << "x86";
223 	#endif
224 
225 	delete[] lpVersionInfo;
226 	delete[] filePath;
227 
228 	return oss.str();
229 #else
230 	struct utsname osinfo;
231 	uname(&osinfo);
232 	return std::string(osinfo.sysname) + "/"
233 		+ osinfo.release + " " + osinfo.machine;
234 #endif
235 }
236 
237 
getCurrentWorkingDir(char * buf,size_t len)238 bool getCurrentWorkingDir(char *buf, size_t len)
239 {
240 #ifdef _WIN32
241 	DWORD ret = GetCurrentDirectory(len, buf);
242 	return (ret != 0) && (ret <= len);
243 #else
244 	return getcwd(buf, len);
245 #endif
246 }
247 
248 
getExecPathFromProcfs(char * buf,size_t buflen)249 bool getExecPathFromProcfs(char *buf, size_t buflen)
250 {
251 #ifndef _WIN32
252 	buflen--;
253 
254 	ssize_t len;
255 	if ((len = readlink("/proc/self/exe",     buf, buflen)) == -1 &&
256 		(len = readlink("/proc/curproc/file", buf, buflen)) == -1 &&
257 		(len = readlink("/proc/curproc/exe",  buf, buflen)) == -1)
258 		return false;
259 
260 	buf[len] = '\0';
261 	return true;
262 #else
263 	return false;
264 #endif
265 }
266 
267 //// Windows
268 #if defined(_WIN32)
269 
getCurrentExecPath(char * buf,size_t len)270 bool getCurrentExecPath(char *buf, size_t len)
271 {
272 	DWORD written = GetModuleFileNameA(NULL, buf, len);
273 	if (written == 0 || written == len)
274 		return false;
275 
276 	return true;
277 }
278 
279 
280 //// Linux
281 #elif defined(__linux__)
282 
getCurrentExecPath(char * buf,size_t len)283 bool getCurrentExecPath(char *buf, size_t len)
284 {
285 	if (!getExecPathFromProcfs(buf, len))
286 		return false;
287 
288 	return true;
289 }
290 
291 
292 //// Mac OS X, Darwin
293 #elif defined(__APPLE__)
294 
getCurrentExecPath(char * buf,size_t len)295 bool getCurrentExecPath(char *buf, size_t len)
296 {
297 	uint32_t lenb = (uint32_t)len;
298 	if (_NSGetExecutablePath(buf, &lenb) == -1)
299 		return false;
300 
301 	return true;
302 }
303 
304 
305 //// FreeBSD, NetBSD, DragonFlyBSD
306 #elif defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__)
307 
getCurrentExecPath(char * buf,size_t len)308 bool getCurrentExecPath(char *buf, size_t len)
309 {
310 	// Try getting path from procfs first, since valgrind
311 	// doesn't work with the latter
312 	if (getExecPathFromProcfs(buf, len))
313 		return true;
314 
315 	int mib[4];
316 
317 	mib[0] = CTL_KERN;
318 	mib[1] = KERN_PROC;
319 	mib[2] = KERN_PROC_PATHNAME;
320 	mib[3] = -1;
321 
322 	if (sysctl(mib, 4, buf, &len, NULL, 0) == -1)
323 		return false;
324 
325 	return true;
326 }
327 
328 #elif defined(__HAIKU__)
329 
getCurrentExecPath(char * buf,size_t len)330 bool getCurrentExecPath(char *buf, size_t len)
331 {
332 	return find_path(B_APP_IMAGE_SYMBOL, B_FIND_PATH_IMAGE_PATH, NULL, buf, len) == B_OK;
333 }
334 
335 //// Solaris
336 #elif defined(__sun) || defined(sun)
337 
getCurrentExecPath(char * buf,size_t len)338 bool getCurrentExecPath(char *buf, size_t len)
339 {
340 	const char *exec = getexecname();
341 	if (exec == NULL)
342 		return false;
343 
344 	if (strlcpy(buf, exec, len) >= len)
345 		return false;
346 
347 	return true;
348 }
349 
350 
351 // HP-UX
352 #elif defined(__hpux)
353 
getCurrentExecPath(char * buf,size_t len)354 bool getCurrentExecPath(char *buf, size_t len)
355 {
356 	struct pst_status psts;
357 
358 	if (pstat_getproc(&psts, sizeof(psts), 0, getpid()) == -1)
359 		return false;
360 
361 	if (pstat_getpathname(buf, len, &psts.pst_fid_text) == -1)
362 		return false;
363 
364 	return true;
365 }
366 
367 
368 #else
369 
getCurrentExecPath(char * buf,size_t len)370 bool getCurrentExecPath(char *buf, size_t len)
371 {
372 	return false;
373 }
374 
375 #endif
376 
377 
378 //// Non-Windows
379 #if !defined(_WIN32)
380 
getHomeOrFail()381 const char *getHomeOrFail()
382 {
383 	const char *home = getenv("HOME");
384 	// In rare cases the HOME environment variable may be unset
385 	FATAL_ERROR_IF(!home,
386 		"Required environment variable HOME is not set");
387 	return home;
388 }
389 
390 #endif
391 
392 
393 //// Windows
394 #if defined(_WIN32)
395 
setSystemPaths()396 bool setSystemPaths()
397 {
398 	char buf[BUFSIZ];
399 
400 	// Find path of executable and set path_share relative to it
401 	FATAL_ERROR_IF(!getCurrentExecPath(buf, sizeof(buf)),
402 		"Failed to get current executable path");
403 	pathRemoveFile(buf, '\\');
404 
405 	std::string exepath(buf);
406 
407 	// Use ".\bin\.."
408 	path_share = exepath + "\\..";
409 	if (detectMSVCBuildDir(exepath)) {
410 		// The msvc build dir schould normaly not be present if properly installed,
411 		// but its usefull for debugging.
412 		path_share += DIR_DELIM "..";
413 	}
414 
415 	// Use "C:\Users\<user>\AppData\Roaming\<PROJECT_NAME_C>"
416 	DWORD len = GetEnvironmentVariable("APPDATA", buf, sizeof(buf));
417 	FATAL_ERROR_IF(len == 0 || len > sizeof(buf), "Failed to get APPDATA");
418 
419 	path_user = std::string(buf) + DIR_DELIM + PROJECT_NAME_C;
420 	return true;
421 }
422 
423 
424 //// Linux
425 #elif defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__)
426 
setSystemPaths()427 bool setSystemPaths()
428 {
429 	char buf[BUFSIZ];
430 
431 	if (!getCurrentExecPath(buf, sizeof(buf))) {
432 #ifdef __ANDROID__
433 		errorstream << "Unable to read bindir "<< std::endl;
434 #else
435 		FATAL_ERROR("Unable to read bindir");
436 #endif
437 		return false;
438 	}
439 
440 	pathRemoveFile(buf, '/');
441 	std::string bindir(buf);
442 
443 	// Find share directory from these.
444 	// It is identified by containing the subdirectory "builtin".
445 	std::list<std::string> trylist;
446 	std::string static_sharedir = STATIC_SHAREDIR;
447 	if (!static_sharedir.empty() && static_sharedir != ".")
448 		trylist.push_back(static_sharedir);
449 
450 	trylist.push_back(bindir + DIR_DELIM ".." DIR_DELIM "share"
451 		DIR_DELIM + PROJECT_NAME);
452 	trylist.push_back(bindir + DIR_DELIM "..");
453 
454 #ifdef __ANDROID__
455 	trylist.push_back(path_user);
456 #endif
457 
458 	for (std::list<std::string>::const_iterator
459 			i = trylist.begin(); i != trylist.end(); ++i) {
460 		const std::string &trypath = *i;
461 		if (!fs::PathExists(trypath) ||
462 			!fs::PathExists(trypath + DIR_DELIM + "builtin")) {
463 			warningstream << "system-wide share not found at \""
464 					<< trypath << "\""<< std::endl;
465 			continue;
466 		}
467 
468 		// Warn if was not the first alternative
469 		if (i != trylist.begin()) {
470 			warningstream << "system-wide share found at \""
471 					<< trypath << "\"" << std::endl;
472 		}
473 
474 		path_share = trypath;
475 		break;
476 	}
477 
478 #ifndef __ANDROID__
479 	path_user = std::string(getHomeOrFail()) + DIR_DELIM "."
480 		+ PROJECT_NAME;
481 #endif
482 
483 	return true;
484 }
485 
486 
487 //// Mac OS X
488 #elif defined(__APPLE__)
489 
setSystemPaths()490 bool setSystemPaths()
491 {
492 	CFBundleRef main_bundle = CFBundleGetMainBundle();
493 	CFURLRef resources_url = CFBundleCopyResourcesDirectoryURL(main_bundle);
494 	char path[PATH_MAX];
495 	if (CFURLGetFileSystemRepresentation(resources_url,
496 			TRUE, (UInt8 *)path, PATH_MAX)) {
497 		path_share = std::string(path);
498 	} else {
499 		warningstream << "Could not determine bundle resource path" << std::endl;
500 	}
501 	CFRelease(resources_url);
502 
503 	path_user = std::string(getHomeOrFail())
504 		+ "/Library/Application Support/"
505 		+ PROJECT_NAME;
506 	return true;
507 }
508 
509 
510 #else
511 
setSystemPaths()512 bool setSystemPaths()
513 {
514 	path_share = STATIC_SHAREDIR;
515 	path_user  = std::string(getHomeOrFail()) + DIR_DELIM "."
516 		+ lowercase(PROJECT_NAME);
517 	return true;
518 }
519 
520 
521 #endif
522 
migrateCachePath()523 void migrateCachePath()
524 {
525 	const std::string local_cache_path = path_user + DIR_DELIM + "cache";
526 
527 	// Delete tmp folder if it exists (it only ever contained
528 	// a temporary ogg file, which is no longer used).
529 	if (fs::PathExists(local_cache_path + DIR_DELIM + "tmp"))
530 		fs::RecursiveDelete(local_cache_path + DIR_DELIM + "tmp");
531 
532 	// Bail if migration impossible
533 	if (path_cache == local_cache_path || !fs::PathExists(local_cache_path)
534 			|| fs::PathExists(path_cache)) {
535 		return;
536 	}
537 	if (!fs::Rename(local_cache_path, path_cache)) {
538 		errorstream << "Failed to migrate local cache path "
539 			"to system path!" << std::endl;
540 	}
541 }
542 
initializePaths()543 void initializePaths()
544 {
545 #if RUN_IN_PLACE
546 	char buf[BUFSIZ];
547 
548 	infostream << "Using relative paths (RUN_IN_PLACE)" << std::endl;
549 
550 	bool success =
551 		getCurrentExecPath(buf, sizeof(buf)) ||
552 		getExecPathFromProcfs(buf, sizeof(buf));
553 
554 	if (success) {
555 		pathRemoveFile(buf, DIR_DELIM_CHAR);
556 		std::string execpath(buf);
557 
558 		path_share = execpath + DIR_DELIM "..";
559 		path_user  = execpath + DIR_DELIM "..";
560 
561 		if (detectMSVCBuildDir(execpath)) {
562 			path_share += DIR_DELIM "..";
563 			path_user  += DIR_DELIM "..";
564 		}
565 	} else {
566 		errorstream << "Failed to get paths by executable location, "
567 			"trying cwd" << std::endl;
568 
569 		if (!getCurrentWorkingDir(buf, sizeof(buf)))
570 			FATAL_ERROR("Ran out of methods to get paths");
571 
572 		size_t cwdlen = strlen(buf);
573 		if (cwdlen >= 1 && buf[cwdlen - 1] == DIR_DELIM_CHAR) {
574 			cwdlen--;
575 			buf[cwdlen] = '\0';
576 		}
577 
578 		if (cwdlen >= 4 && !strcmp(buf + cwdlen - 4, DIR_DELIM "bin"))
579 			pathRemoveFile(buf, DIR_DELIM_CHAR);
580 
581 		std::string execpath(buf);
582 
583 		path_share = execpath;
584 		path_user  = execpath;
585 	}
586 	path_cache = path_user + DIR_DELIM + "cache";
587 #else
588 	infostream << "Using system-wide paths (NOT RUN_IN_PLACE)" << std::endl;
589 
590 	if (!setSystemPaths())
591 		errorstream << "Failed to get one or more system-wide path" << std::endl;
592 
593 
594 #  ifdef _WIN32
595 	path_cache = path_user + DIR_DELIM + "cache";
596 #  else
597 	// Initialize path_cache
598 	// First try $XDG_CACHE_HOME/PROJECT_NAME
599 	const char *cache_dir = getenv("XDG_CACHE_HOME");
600 	const char *home_dir = getenv("HOME");
601 	if (cache_dir) {
602 		path_cache = std::string(cache_dir) + DIR_DELIM + PROJECT_NAME;
603 	} else if (home_dir) {
604 		// Then try $HOME/.cache/PROJECT_NAME
605 		path_cache = std::string(home_dir) + DIR_DELIM + ".cache"
606 			+ DIR_DELIM + PROJECT_NAME;
607 	} else {
608 		// If neither works, use $PATH_USER/cache
609 		path_cache = path_user + DIR_DELIM + "cache";
610 	}
611 	// Migrate cache folder to new location if possible
612 	migrateCachePath();
613 #  endif // _WIN32
614 #endif // RUN_IN_PLACE
615 
616 	infostream << "Detected share path: " << path_share << std::endl;
617 	infostream << "Detected user path: " << path_user << std::endl;
618 	infostream << "Detected cache path: " << path_cache << std::endl;
619 
620 #if USE_GETTEXT
621 	bool found_localedir = false;
622 #  ifdef STATIC_LOCALEDIR
623 	/* STATIC_LOCALEDIR may be a generalized path such as /usr/share/locale that
624 	 * doesn't necessarily contain our locale files, so check data path first. */
625 	path_locale = getDataPath("locale");
626 	if (fs::PathExists(path_locale)) {
627 		found_localedir = true;
628 		infostream << "Using in-place locale directory " << path_locale
629 			<< " even though a static one was provided." << std::endl;
630 	} else if (STATIC_LOCALEDIR[0] && fs::PathExists(STATIC_LOCALEDIR)) {
631 		found_localedir = true;
632 		path_locale = STATIC_LOCALEDIR;
633 		infostream << "Using static locale directory " << STATIC_LOCALEDIR
634 			<< std::endl;
635 	}
636 #  else
637 	path_locale = getDataPath("locale");
638 	if (fs::PathExists(path_locale)) {
639 		found_localedir = true;
640 	}
641 #  endif
642 	if (!found_localedir) {
643 		warningstream << "Couldn't find a locale directory!" << std::endl;
644 	}
645 #endif  // USE_GETTEXT
646 }
647 
648 ////
649 //// OS-specific Secure Random
650 ////
651 
652 #ifdef WIN32
653 
secure_rand_fill_buf(void * buf,size_t len)654 bool secure_rand_fill_buf(void *buf, size_t len)
655 {
656 	HCRYPTPROV wctx;
657 
658 	if (!CryptAcquireContext(&wctx, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
659 		return false;
660 
661 	CryptGenRandom(wctx, len, (BYTE *)buf);
662 	CryptReleaseContext(wctx, 0);
663 	return true;
664 }
665 
666 #else
667 
secure_rand_fill_buf(void * buf,size_t len)668 bool secure_rand_fill_buf(void *buf, size_t len)
669 {
670 	// N.B.  This function checks *only* for /dev/urandom, because on most
671 	// common OSes it is non-blocking, whereas /dev/random is blocking, and it
672 	// is exceptionally uncommon for there to be a situation where /dev/random
673 	// exists but /dev/urandom does not.  This guesswork is necessary since
674 	// random devices are not covered by any POSIX standard...
675 	FILE *fp = fopen("/dev/urandom", "rb");
676 	if (!fp)
677 		return false;
678 
679 	bool success = fread(buf, len, 1, fp) == 1;
680 
681 	fclose(fp);
682 	return success;
683 }
684 
685 #endif
686 
attachOrCreateConsole()687 void attachOrCreateConsole()
688 {
689 #ifdef _WIN32
690 	static bool consoleAllocated = false;
691 	const bool redirected = (_fileno(stdout) == -2 || _fileno(stdout) == -1); // If output is redirected to e.g a file
692 	if (!consoleAllocated && redirected && (AttachConsole(ATTACH_PARENT_PROCESS) || AllocConsole())) {
693 		freopen("CONOUT$", "w", stdout);
694 		freopen("CONOUT$", "w", stderr);
695 		consoleAllocated = true;
696 	}
697 #endif
698 }
699 
mt_snprintf(char * buf,const size_t buf_size,const char * fmt,...)700 int mt_snprintf(char *buf, const size_t buf_size, const char *fmt, ...)
701 {
702 	// https://msdn.microsoft.com/en-us/library/bt7tawza.aspx
703 	//  Many of the MSVC / Windows printf-style functions do not support positional
704 	//  arguments (eg. "%1$s"). We just forward the call to vsnprintf for sane
705 	//  platforms, but defer to _vsprintf_p on MSVC / Windows.
706 	// https://github.com/FFmpeg/FFmpeg/blob/5ae9fa13f5ac640bec113120d540f70971aa635d/compat/msvcrt/snprintf.c#L46
707 	//  _vsprintf_p has to be shimmed with _vscprintf_p on -1 (for an example see
708 	//  above FFmpeg link).
709 	va_list args;
710 	va_start(args, fmt);
711 #ifndef _MSC_VER
712 	int c = vsnprintf(buf, buf_size, fmt, args);
713 #else  // _MSC_VER
714 	int c = _vsprintf_p(buf, buf_size, fmt, args);
715 	if (c == -1)
716 		c = _vscprintf_p(fmt, args);
717 #endif // _MSC_VER
718 	va_end(args);
719 	return c;
720 }
721 
open_uri(const std::string & uri)722 static bool open_uri(const std::string &uri)
723 {
724 	if (uri.find_first_of("\r\n") != std::string::npos) {
725 		errorstream << "Unable to open URI as it is invalid, contains new line: " << uri << std::endl;
726 		return false;
727 	}
728 
729 #if defined(_WIN32)
730 	return (intptr_t)ShellExecuteA(NULL, NULL, uri.c_str(), NULL, NULL, SW_SHOWNORMAL) > 32;
731 #elif defined(__ANDROID__)
732 	openURIAndroid(uri);
733 	return true;
734 #elif defined(__APPLE__)
735 	const char *argv[] = {"open", uri.c_str(), NULL};
736 	return posix_spawnp(NULL, "open", NULL, NULL, (char**)argv,
737 		(*_NSGetEnviron())) == 0;
738 #else
739 	const char *argv[] = {"xdg-open", uri.c_str(), NULL};
740 	return posix_spawnp(NULL, "xdg-open", NULL, NULL, (char**)argv, environ) == 0;
741 #endif
742 }
743 
open_url(const std::string & url)744 bool open_url(const std::string &url)
745 {
746 	if (url.substr(0, 7) != "http://" && url.substr(0, 8) != "https://") {
747 		errorstream << "Unable to open browser as URL is missing schema: " << url << std::endl;
748 		return false;
749 	}
750 
751 	return open_uri(url);
752 }
753 
open_directory(const std::string & path)754 bool open_directory(const std::string &path)
755 {
756 	if (!fs::IsDir(path)) {
757 		errorstream << "Unable to open directory as it does not exist: " << path << std::endl;
758 		return false;
759 	}
760 
761 	return open_uri(path);
762 }
763 
764 // Load performance counter frequency only once at startup
765 #ifdef _WIN32
766 
get_perf_freq()767 inline double get_perf_freq()
768 {
769 	LARGE_INTEGER freq;
770 	QueryPerformanceFrequency(&freq);
771 	return freq.QuadPart;
772 }
773 
774 double perf_freq = get_perf_freq();
775 
776 #endif
777 
778 } //namespace porting
779