compat/mingw.c

   1 #include "../git-compat-util.h"
   2 #include "win32.h"
   3 #include "../strbuf.h"
   4
   5 unsigned int _CRT_fmode = _O_BINARY;
   6
   7 #undef open
   8 int mingw_open (const char *filename, int oflags, ...)
   9 {
  10         va_list args;
  11         unsigned mode;
  12         va_start(args, oflags);
  13         mode = va_arg(args, int);
  14         va_end(args);
  15
  16         if (!strcmp(filename, "/dev/null"))
  17                 filename = "nul";
  18         int fd = open(filename, oflags, mode);
  19         if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
  20                 DWORD attrs = GetFileAttributes(filename);
  21                 if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
  22                         errno = EISDIR;
  23         }
  24         return fd;
  25 }
  26
  27 static inline time_t filetime_to_time_t(const FILETIME *ft)
  28 {
  29         long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
  30         winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
  31         winTime /= 10000000;             /* Nano to seconds resolution */
  32         return (time_t)winTime;
  33 }
  34
  35 /* We keep the do_lstat code in a separate function to avoid recursion.
  36  * When a path ends with a slash, the stat will fail with ENOENT. In
  37  * this case, we strip the trailing slashes and stat again.
  38  */
  39 static int do_lstat(const char *file_name, struct stat *buf)
  40 {
  41         WIN32_FILE_ATTRIBUTE_DATA fdata;
  42
  43         if (!(errno = get_file_attr(file_name, &fdata))) {
  44                 buf->st_ino = 0;
  45                 buf->st_gid = 0;
  46                 buf->st_uid = 0;
  47                 buf->st_nlink = 1;
  48                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
  49                 buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
  50                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
  51                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
  52                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
  53                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
  54                 return 0;
  55         }
  56         return -1;
  57 }
  58
  59 /* We provide our own lstat/fstat functions, since the provided
  60  * lstat/fstat functions are so slow. These stat functions are
  61  * tailored for Git's usage (read: fast), and are not meant to be
  62  * complete. Note that Git stat()s are redirected to mingw_lstat()
  63  * too, since Windows doesn't really handle symlinks that well.
  64  */
  65 int mingw_lstat(const char *file_name, struct stat *buf)
  66 {
  67         int namelen;
  68         static char alt_name[PATH_MAX];
  69
  70         if (!do_lstat(file_name, buf))
  71                 return 0;
  72
  73         /* if file_name ended in a '/', Windows returned ENOENT;
  74          * try again without trailing slashes
  75          */
  76         if (errno != ENOENT)
  77                 return -1;
  78
  79         namelen = strlen(file_name);
  80         if (namelen && file_name[namelen-1] != '/')
  81                 return -1;
  82         while (namelen && file_name[namelen-1] == '/')
  83                 --namelen;
  84         if (!namelen || namelen >= PATH_MAX)
  85                 return -1;
  86
  87         memcpy(alt_name, file_name, namelen);
  88         alt_name[namelen] = 0;
  89         return do_lstat(alt_name, buf);
  90 }
  91
  92 #undef fstat
  93 int mingw_fstat(int fd, struct stat *buf)
  94 {
  95         HANDLE fh = (HANDLE)_get_osfhandle(fd);
  96         BY_HANDLE_FILE_INFORMATION fdata;
  97
  98         if (fh == INVALID_HANDLE_VALUE) {
  99                 errno = EBADF;
 100                 return -1;
 101         }
 102         /* direct non-file handles to MS's fstat() */
 103         if (GetFileType(fh) != FILE_TYPE_DISK)
 104                 return fstat(fd, buf);
 105
 106         if (GetFileInformationByHandle(fh, &fdata)) {
 107                 buf->st_ino = 0;
 108                 buf->st_gid = 0;
 109                 buf->st_uid = 0;
 110                 buf->st_nlink = 1;
 111                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 112                 buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
 113                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 114                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 115                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 116                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 117                 return 0;
 118         }
 119         errno = EBADF;
 120         return -1;
 121 }
 122
 123 static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 124 {
 125         long long winTime = t * 10000000LL + 116444736000000000LL;
 126         ft->dwLowDateTime = winTime;
 127         ft->dwHighDateTime = winTime >> 32;
 128 }
 129
 130 int mingw_utime (const char *file_name, const struct utimbuf *times)
 131 {
 132         FILETIME mft, aft;
 133         int fh, rc;
 134
 135         /* must have write permission */
 136         if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
 137                 return -1;
 138
 139         time_t_to_filetime(times->modtime, &mft);
 140         time_t_to_filetime(times->actime, &aft);
 141         if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 142                 errno = EINVAL;
 143                 rc = -1;
 144         } else
 145                 rc = 0;
 146         close(fh);
 147         return rc;
 148 }
 149
 150 unsigned int sleep (unsigned int seconds)
 151 {
 152         Sleep(seconds*1000);
 153         return 0;
 154 }
 155
 156 int mkstemp(char *template)
 157 {
 158         char *filename = mktemp(template);
 159         if (filename == NULL)
 160                 return -1;
 161         return open(filename, O_RDWR | O_CREAT, 0600);
 162 }
 163
 164 int gettimeofday(struct timeval *tv, void *tz)
 165 {
 166         SYSTEMTIME st;
 167         struct tm tm;
 168         GetSystemTime(&st);
 169         tm.tm_year = st.wYear-1900;
 170         tm.tm_mon = st.wMonth-1;
 171         tm.tm_mday = st.wDay;
 172         tm.tm_hour = st.wHour;
 173         tm.tm_min = st.wMinute;
 174         tm.tm_sec = st.wSecond;
 175         tv->tv_sec = tm_to_time_t(&tm);
 176         if (tv->tv_sec < 0)
 177                 return -1;
 178         tv->tv_usec = st.wMilliseconds*1000;
 179         return 0;
 180 }
 181
 182 int pipe(int filedes[2])
 183 {
 184         int fd;
 185         HANDLE h[2], parent;
 186
 187         if (_pipe(filedes, 8192, 0) < 0)
 188                 return -1;
 189
 190         parent = GetCurrentProcess();
 191
 192         if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[0]),
 193                         parent, &h[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 194                 close(filedes[0]);
 195                 close(filedes[1]);
 196                 return -1;
 197         }
 198         if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[1]),
 199                         parent, &h[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 200                 close(filedes[0]);
 201                 close(filedes[1]);
 202                 CloseHandle(h[0]);
 203                 return -1;
 204         }
 205         fd = _open_osfhandle((int)h[0], O_NOINHERIT);
 206         if (fd < 0) {
 207                 close(filedes[0]);
 208                 close(filedes[1]);
 209                 CloseHandle(h[0]);
 210                 CloseHandle(h[1]);
 211                 return -1;
 212         }
 213         close(filedes[0]);
 214         filedes[0] = fd;
 215         fd = _open_osfhandle((int)h[1], O_NOINHERIT);
 216         if (fd < 0) {
 217                 close(filedes[0]);
 218                 close(filedes[1]);
 219                 CloseHandle(h[1]);
 220                 return -1;
 221         }
 222         close(filedes[1]);
 223         filedes[1] = fd;
 224         return 0;
 225 }
 226
 227 int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 228 {
 229         int i, pending;
 230
 231         if (timeout >= 0) {
 232                 if (nfds == 0) {
 233                         Sleep(timeout);
 234                         return 0;
 235                 }
 236                 return errno = EINVAL, error("poll timeout not supported");
 237         }
 238
 239         /* When there is only one fd to wait for, then we pretend that
 240          * input is available and let the actual wait happen when the
 241          * caller invokes read().
 242          */
 243         if (nfds == 1) {
 244                 if (!(ufds[0].events & POLLIN))
 245                         return errno = EINVAL, error("POLLIN not set");
 246                 ufds[0].revents = POLLIN;
 247                 return 0;
 248         }
 249
 250 repeat:
 251         pending = 0;
 252         for (i = 0; i < nfds; i++) {
 253                 DWORD avail = 0;
 254                 HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 255                 if (h == INVALID_HANDLE_VALUE)
 256                         return -1;      /* errno was set */
 257
 258                 if (!(ufds[i].events & POLLIN))
 259                         return errno = EINVAL, error("POLLIN not set");
 260
 261                 /* this emulation works only for pipes */
 262                 if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 263                         int err = GetLastError();
 264                         if (err == ERROR_BROKEN_PIPE) {
 265                                 ufds[i].revents = POLLHUP;
 266                                 pending++;
 267                         } else {
 268                                 errno = EINVAL;
 269                                 return error("PeekNamedPipe failed,"
 270                                         " GetLastError: %u", err);
 271                         }
 272                 } else if (avail) {
 273                         ufds[i].revents = POLLIN;
 274                         pending++;
 275                 } else
 276                         ufds[i].revents = 0;
 277         }
 278         if (!pending) {
 279                 /* The only times that we spin here is when the process
 280                  * that is connected through the pipes is waiting for
 281                  * its own input data to become available. But since
 282                  * the process (pack-objects) is itself CPU intensive,
 283                  * it will happily pick up the time slice that we are
 284                  * relinguishing here.
 285                  */
 286                 Sleep(0);
 287                 goto repeat;
 288         }
 289         return 0;
 290 }
 291
 292 struct tm *gmtime_r(const time_t *timep, struct tm *result)
 293 {
 294         /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 295         memcpy(result, gmtime(timep), sizeof(struct tm));
 296         return result;
 297 }
 298
 299 struct tm *localtime_r(const time_t *timep, struct tm *result)
 300 {
 301         /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 302         memcpy(result, localtime(timep), sizeof(struct tm));
 303         return result;
 304 }
 305
 306 #undef getcwd
 307 char *mingw_getcwd(char *pointer, int len)
 308 {
 309         int i;
 310         char *ret = getcwd(pointer, len);
 311         if (!ret)
 312                 return ret;
 313         for (i = 0; pointer[i]; i++)
 314                 if (pointer[i] == '\\')
 315                         pointer[i] = '/';
 316         return ret;
 317 }
 318
 319 #undef getenv
 320 char *mingw_getenv(const char *name)
 321 {
 322         char *result = getenv(name);
 323         if (!result && !strcmp(name, "TMPDIR")) {
 324                 /* on Windows it is TMP and TEMP */
 325                 result = getenv("TMP");
 326                 if (!result)
 327                         result = getenv("TEMP");
 328         }
 329         return result;
 330 }
 331
 332 /*
 333  * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 334  * (Parsing C++ Command-Line Arguments)
 335  */
 336 static const char *quote_arg(const char *arg)
 337 {
 338         /* count chars to quote */
 339         int len = 0, n = 0;
 340         int force_quotes = 0;
 341         char *q, *d;
 342         const char *p = arg;
 343         if (!*p) force_quotes = 1;
 344         while (*p) {
 345                 if (isspace(*p) || *p == '*' || *p == '?' || *p == '{')
 346                         force_quotes = 1;
 347                 else if (*p == '"')
 348                         n++;
 349                 else if (*p == '\\') {
 350                         int count = 0;
 351                         while (*p == '\\') {
 352                                 count++;
 353                                 p++;
 354                                 len++;
 355                         }
 356                         if (*p == '"')
 357                                 n += count*2 + 1;
 358                         continue;
 359                 }
 360                 len++;
 361                 p++;
 362         }
 363         if (!force_quotes && n == 0)
 364                 return arg;
 365
 366         /* insert \ where necessary */
 367         d = q = xmalloc(len+n+3);
 368         *d++ = '"';
 369         while (*arg) {
 370                 if (*arg == '"')
 371                         *d++ = '\\';
 372                 else if (*arg == '\\') {
 373                         int count = 0;
 374                         while (*arg == '\\') {
 375                                 count++;
 376                                 *d++ = *arg++;
 377                         }
 378                         if (*arg == '"') {
 379                                 while (count-- > 0)
 380                                         *d++ = '\\';
 381                                 *d++ = '\\';
 382                         }
 383                 }
 384                 *d++ = *arg++;
 385         }
 386         *d++ = '"';
 387         *d++ = 0;
 388         return q;
 389 }
 390
 391 static const char *parse_interpreter(const char *cmd)
 392 {
 393         static char buf[100];
 394         char *p, *opt;
 395         int n, fd;
 396
 397         /* don't even try a .exe */
 398         n = strlen(cmd);
 399         if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 400                 return NULL;
 401
 402         fd = open(cmd, O_RDONLY);
 403         if (fd < 0)
 404                 return NULL;
 405         n = read(fd, buf, sizeof(buf)-1);
 406         close(fd);
 407         if (n < 4)      /* at least '#!/x' and not error */
 408                 return NULL;
 409
 410         if (buf[0] != '#' || buf[1] != '!')
 411                 return NULL;
 412         buf[n] = '\0';
 413         p = strchr(buf, '\n');
 414         if (!p)
 415                 return NULL;
 416
 417         *p = '\0';
 418         if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 419                 return NULL;
 420         /* strip options */
 421         if ((opt = strchr(p+1, ' ')))
 422                 *opt = '\0';
 423         return p+1;
 424 }
 425
 426 /*
 427  * Splits the PATH into parts.
 428  */
 429 static char **get_path_split(void)
 430 {
 431         char *p, **path, *envpath = getenv("PATH");
 432         int i, n = 0;
 433
 434         if (!envpath || !*envpath)
 435                 return NULL;
 436
 437         envpath = xstrdup(envpath);
 438         p = envpath;
 439         while (p) {
 440                 char *dir = p;
 441                 p = strchr(p, ';');
 442                 if (p) *p++ = '\0';
 443                 if (*dir) {     /* not earlier, catches series of ; */
 444                         ++n;
 445                 }
 446         }
 447         if (!n)
 448                 return NULL;
 449
 450         path = xmalloc((n+1)*sizeof(char*));
 451         p = envpath;
 452         i = 0;
 453         do {
 454                 if (*p)
 455                         path[i++] = xstrdup(p);
 456                 p = p+strlen(p)+1;
 457         } while (i < n);
 458         path[i] = NULL;
 459
 460         free(envpath);
 461
 462         return path;
 463 }
 464
 465 static void free_path_split(char **path)
 466 {
 467         if (!path)
 468                 return;
 469
 470         char **p = path;
 471         while (*p)
 472                 free(*p++);
 473         free(path);
 474 }
 475
 476 /*
 477  * exe_only means that we only want to detect .exe files, but not scripts
 478  * (which do not have an extension)
 479  */
 480 static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 481 {
 482         char path[MAX_PATH];
 483         snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 484
 485         if (!isexe && access(path, F_OK) == 0)
 486                 return xstrdup(path);
 487         path[strlen(path)-4] = '\0';
 488         if ((!exe_only || isexe) && access(path, F_OK) == 0)
 489                 if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 490                         return xstrdup(path);
 491         return NULL;
 492 }
 493
 494 /*
 495  * Determines the absolute path of cmd using the the split path in path.
 496  * If cmd contains a slash or backslash, no lookup is performed.
 497  */
 498 static char *path_lookup(const char *cmd, char **path, int exe_only)
 499 {
 500         char *prog = NULL;
 501         int len = strlen(cmd);
 502         int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 503
 504         if (strchr(cmd, '/') || strchr(cmd, '\\'))
 505                 prog = xstrdup(cmd);
 506
 507         while (!prog && *path)
 508                 prog = lookup_prog(*path++, cmd, isexe, exe_only);
 509
 510         return prog;
 511 }
 512
 513 static int env_compare(const void *a, const void *b)
 514 {
 515         char *const *ea = a;
 516         char *const *eb = b;
 517         return strcasecmp(*ea, *eb);
 518 }
 519
 520 static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 521                            int prepend_cmd)
 522 {
 523         STARTUPINFO si;
 524         PROCESS_INFORMATION pi;
 525         struct strbuf envblk, args;
 526         unsigned flags;
 527         BOOL ret;
 528
 529         /* Determine whether or not we are associated to a console */
 530         HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 531                         FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 532                         FILE_ATTRIBUTE_NORMAL, NULL);
 533         if (cons == INVALID_HANDLE_VALUE) {
 534                 /* There is no console associated with this process.
 535                  * Since the child is a console process, Windows
 536                  * would normally create a console window. But
 537                  * since we'll be redirecting std streams, we do
 538                  * not need the console.
 539                  * It is necessary to use DETACHED_PROCESS
 540                  * instead of CREATE_NO_WINDOW to make ssh
 541                  * recognize that it has no console.
 542                  */
 543                 flags = DETACHED_PROCESS;
 544         } else {
 545                 /* There is already a console. If we specified
 546                  * DETACHED_PROCESS here, too, Windows would
 547                  * disassociate the child from the console.
 548                  * The same is true for CREATE_NO_WINDOW.
 549                  * Go figure!
 550                  */
 551                 flags = 0;
 552                 CloseHandle(cons);
 553         }
 554         memset(&si, 0, sizeof(si));
 555         si.cb = sizeof(si);
 556         si.dwFlags = STARTF_USESTDHANDLES;
 557         si.hStdInput = (HANDLE) _get_osfhandle(0);
 558         si.hStdOutput = (HANDLE) _get_osfhandle(1);
 559         si.hStdError = (HANDLE) _get_osfhandle(2);
 560
 561         /* concatenate argv, quoting args as we go */
 562         strbuf_init(&args, 0);
 563         if (prepend_cmd) {
 564                 char *quoted = (char *)quote_arg(cmd);
 565                 strbuf_addstr(&args, quoted);
 566                 if (quoted != cmd)
 567                         free(quoted);
 568         }
 569         for (; *argv; argv++) {
 570                 char *quoted = (char *)quote_arg(*argv);
 571                 if (*args.buf)
 572                         strbuf_addch(&args, ' ');
 573                 strbuf_addstr(&args, quoted);
 574                 if (quoted != *argv)
 575                         free(quoted);
 576         }
 577
 578         if (env) {
 579                 int count = 0;
 580                 char **e, **sorted_env;
 581
 582                 for (e = env; *e; e++)
 583                         count++;
 584
 585                 /* environment must be sorted */
 586                 sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 587                 memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 588                 qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 589
 590                 strbuf_init(&envblk, 0);
 591                 for (e = sorted_env; *e; e++) {
 592                         strbuf_addstr(&envblk, *e);
 593                         strbuf_addch(&envblk, '\0');
 594                 }
 595                 free(sorted_env);
 596         }
 597
 598         memset(&pi, 0, sizeof(pi));
 599         ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 600                 env ? envblk.buf : NULL, NULL, &si, &pi);
 601
 602         if (env)
 603                 strbuf_release(&envblk);
 604         strbuf_release(&args);
 605
 606         if (!ret) {
 607                 errno = ENOENT;
 608                 return -1;
 609         }
 610         CloseHandle(pi.hThread);
 611         return (pid_t)pi.hProcess;
 612 }
 613
 614 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
 615 {
 616         pid_t pid;
 617         char **path = get_path_split();
 618         char *prog = path_lookup(cmd, path, 0);
 619
 620         if (!prog) {
 621                 errno = ENOENT;
 622                 pid = -1;
 623         }
 624         else {
 625                 const char *interpr = parse_interpreter(prog);
 626
 627                 if (interpr) {
 628                         const char *argv0 = argv[0];
 629                         char *iprog = path_lookup(interpr, path, 1);
 630                         argv[0] = prog;
 631                         if (!iprog) {
 632                                 errno = ENOENT;
 633                                 pid = -1;
 634                         }
 635                         else {
 636                                 pid = mingw_spawnve(iprog, argv, env, 1);
 637                                 free(iprog);
 638                         }
 639                         argv[0] = argv0;
 640                 }
 641                 else
 642                         pid = mingw_spawnve(prog, argv, env, 0);
 643                 free(prog);
 644         }
 645         free_path_split(path);
 646         return pid;
 647 }
 648
 649 static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 650 {
 651         const char *interpr = parse_interpreter(cmd);
 652         char **path;
 653         char *prog;
 654         int pid = 0;
 655
 656         if (!interpr)
 657                 return 0;
 658         path = get_path_split();
 659         prog = path_lookup(interpr, path, 1);
 660         if (prog) {
 661                 int argc = 0;
 662                 const char **argv2;
 663                 while (argv[argc]) argc++;
 664                 argv2 = xmalloc(sizeof(*argv) * (argc+1));
 665                 argv2[0] = (char *)cmd; /* full path to the script file */
 666                 memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 667                 pid = mingw_spawnve(prog, argv2, env, 1);
 668                 if (pid >= 0) {
 669                         int status;
 670                         if (waitpid(pid, &status, 0) < 0)
 671                                 status = 255;
 672                         exit(status);
 673                 }
 674                 pid = 1;        /* indicate that we tried but failed */
 675                 free(prog);
 676                 free(argv2);
 677         }
 678         free_path_split(path);
 679         return pid;
 680 }
 681
 682 static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 683 {
 684         /* check if git_command is a shell script */
 685         if (!try_shell_exec(cmd, argv, (char **)env)) {
 686                 int pid, status;
 687
 688                 pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 689                 if (pid < 0)
 690                         return;
 691                 if (waitpid(pid, &status, 0) < 0)
 692                         status = 255;
 693                 exit(status);
 694         }
 695 }
 696
 697 void mingw_execvp(const char *cmd, char *const *argv)
 698 {
 699         char **path = get_path_split();
 700         char *prog = path_lookup(cmd, path, 0);
 701
 702         if (prog) {
 703                 mingw_execve(prog, argv, environ);
 704                 free(prog);
 705         } else
 706                 errno = ENOENT;
 707
 708         free_path_split(path);
 709 }
 710
 711 char **copy_environ()
 712 {
 713         char **env;
 714         int i = 0;
 715         while (environ[i])
 716                 i++;
 717         env = xmalloc((i+1)*sizeof(*env));
 718         for (i = 0; environ[i]; i++)
 719                 env[i] = xstrdup(environ[i]);
 720         env[i] = NULL;
 721         return env;
 722 }
 723
 724 void free_environ(char **env)
 725 {
 726         int i;
 727         for (i = 0; env[i]; i++)
 728                 free(env[i]);
 729         free(env);
 730 }
 731
 732 static int lookup_env(char **env, const char *name, size_t nmln)
 733 {
 734         int i;
 735
 736         for (i = 0; env[i]; i++) {
 737                 if (0 == strncmp(env[i], name, nmln)
 738                     && '=' == env[i][nmln])
 739                         /* matches */
 740                         return i;
 741         }
 742         return -1;
 743 }
 744
 745 /*
 746  * If name contains '=', then sets the variable, otherwise it unsets it
 747  */
 748 char **env_setenv(char **env, const char *name)
 749 {
 750         char *eq = strchrnul(name, '=');
 751         int i = lookup_env(env, name, eq-name);
 752
 753         if (i < 0) {
 754                 if (*eq) {
 755                         for (i = 0; env[i]; i++)
 756                                 ;
 757                         env = xrealloc(env, (i+2)*sizeof(*env));
 758                         env[i] = xstrdup(name);
 759                         env[i+1] = NULL;
 760                 }
 761         }
 762         else {
 763                 free(env[i]);
 764                 if (*eq)
 765                         env[i] = xstrdup(name);
 766                 else
 767                         for (; env[i]; i++)
 768                                 env[i] = env[i+1];
 769         }
 770         return env;
 771 }
 772
 773 /* this is the first function to call into WS_32; initialize it */
 774 #undef gethostbyname
 775 struct hostent *mingw_gethostbyname(const char *host)
 776 {
 777         WSADATA wsa;
 778
 779         if (WSAStartup(MAKEWORD(2,2), &wsa))
 780                 die("unable to initialize winsock subsystem, error %d",
 781                         WSAGetLastError());
 782         atexit((void(*)(void)) WSACleanup);
 783         return gethostbyname(host);
 784 }
 785
 786 int mingw_socket(int domain, int type, int protocol)
 787 {
 788         int sockfd;
 789         SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
 790         if (s == INVALID_SOCKET) {
 791                 /*
 792                  * WSAGetLastError() values are regular BSD error codes
 793                  * biased by WSABASEERR.
 794                  * However, strerror() does not know about networking
 795                  * specific errors, which are values beginning at 38 or so.
 796                  * Therefore, we choose to leave the biased error code
 797                  * in errno so that _if_ someone looks up the code somewhere,
 798                  * then it is at least the number that are usually listed.
 799                  */
 800                 errno = WSAGetLastError();
 801                 return -1;
 802         }
 803         /* convert into a file descriptor */
 804         if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
 805                 closesocket(s);
 806                 return error("unable to make a socket file descriptor: %s",
 807                         strerror(errno));
 808         }
 809         return sockfd;
 810 }
 811
 812 #undef connect
 813 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
 814 {
 815         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
 816         return connect(s, sa, sz);
 817 }
 818
 819 #undef rename
 820 int mingw_rename(const char *pold, const char *pnew)
 821 {
 822         DWORD attrs;
 823
 824         /*
 825          * Try native rename() first to get errno right.
 826          * It is based on MoveFile(), which cannot overwrite existing files.
 827          */
 828         if (!rename(pold, pnew))
 829                 return 0;
 830         if (errno != EEXIST)
 831                 return -1;
 832         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
 833                 return 0;
 834         /* TODO: translate more errors */
 835         if (GetLastError() == ERROR_ACCESS_DENIED &&
 836             (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
 837                 if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
 838                         errno = EISDIR;
 839                         return -1;
 840                 }
 841                 if ((attrs & FILE_ATTRIBUTE_READONLY) &&
 842                     SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
 843                         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
 844                                 return 0;
 845                         /* revert file attributes on failure */
 846                         SetFileAttributes(pnew, attrs);
 847                 }
 848         }
 849         errno = EACCES;
 850         return -1;
 851 }
 852
 853 struct passwd *getpwuid(int uid)
 854 {
 855         static char user_name[100];
 856         static struct passwd p;
 857
 858         DWORD len = sizeof(user_name);
 859         if (!GetUserName(user_name, &len))
 860                 return NULL;
 861         p.pw_name = user_name;
 862         p.pw_gecos = "unknown";
 863         p.pw_dir = NULL;
 864         return &p;
 865 }
 866
 867 static HANDLE timer_event;
 868 static HANDLE timer_thread;
 869 static int timer_interval;
 870 static int one_shot;
 871 static sig_handler_t timer_fn = SIG_DFL;
 872
 873 /* The timer works like this:
 874  * The thread, ticktack(), is a trivial routine that most of the time
 875  * only waits to receive the signal to terminate. The main thread tells
 876  * the thread to terminate by setting the timer_event to the signalled
 877  * state.
 878  * But ticktack() interrupts the wait state after the timer's interval
 879  * length to call the signal handler.
 880  */
 881
 882 static __stdcall unsigned ticktack(void *dummy)
 883 {
 884         while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
 885                 if (timer_fn == SIG_DFL)
 886                         die("Alarm");
 887                 if (timer_fn != SIG_IGN)
 888                         timer_fn(SIGALRM);
 889                 if (one_shot)
 890                         break;
 891         }
 892         return 0;
 893 }
 894
 895 static int start_timer_thread(void)
 896 {
 897         timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
 898         if (timer_event) {
 899                 timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
 900                 if (!timer_thread )
 901                         return errno = ENOMEM,
 902                                 error("cannot start timer thread");
 903         } else
 904                 return errno = ENOMEM,
 905                         error("cannot allocate resources for timer");
 906         return 0;
 907 }
 908
 909 static void stop_timer_thread(void)
 910 {
 911         if (timer_event)
 912                 SetEvent(timer_event);  /* tell thread to terminate */
 913         if (timer_thread) {
 914                 int rc = WaitForSingleObject(timer_thread, 1000);
 915                 if (rc == WAIT_TIMEOUT)
 916                         error("timer thread did not terminate timely");
 917                 else if (rc != WAIT_OBJECT_0)
 918                         error("waiting for timer thread failed: %lu",
 919                               GetLastError());
 920                 CloseHandle(timer_thread);
 921         }
 922         if (timer_event)
 923                 CloseHandle(timer_event);
 924         timer_event = NULL;
 925         timer_thread = NULL;
 926 }
 927
 928 static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
 929 {
 930         return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
 931 }
 932
 933 int setitimer(int type, struct itimerval *in, struct itimerval *out)
 934 {
 935         static const struct timeval zero;
 936         static int atexit_done;
 937
 938         if (out != NULL)
 939                 return errno = EINVAL,
 940                         error("setitimer param 3 != NULL not implemented");
 941         if (!is_timeval_eq(&in->it_interval, &zero) &&
 942             !is_timeval_eq(&in->it_interval, &in->it_value))
 943                 return errno = EINVAL,
 944                         error("setitimer: it_interval must be zero or eq it_value");
 945
 946         if (timer_thread)
 947                 stop_timer_thread();
 948
 949         if (is_timeval_eq(&in->it_value, &zero) &&
 950             is_timeval_eq(&in->it_interval, &zero))
 951                 return 0;
 952
 953         timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
 954         one_shot = is_timeval_eq(&in->it_interval, &zero);
 955         if (!atexit_done) {
 956                 atexit(stop_timer_thread);
 957                 atexit_done = 1;
 958         }
 959         return start_timer_thread();
 960 }
 961
 962 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
 963 {
 964         if (sig != SIGALRM)
 965                 return errno = EINVAL,
 966                         error("sigaction only implemented for SIGALRM");
 967         if (out != NULL)
 968                 return errno = EINVAL,
 969                         error("sigaction: param 3 != NULL not implemented");
 970
 971         timer_fn = in->sa_handler;
 972         return 0;
 973 }
 974
 975 #undef signal
 976 sig_handler_t mingw_signal(int sig, sig_handler_t handler)
 977 {
 978         if (sig != SIGALRM)
 979                 return signal(sig, handler);
 980         sig_handler_t old = timer_fn;
 981         timer_fn = handler;
 982         return old;
 983 }
 984
 985 static const char *make_backslash_path(const char *path)
 986 {
 987         static char buf[PATH_MAX + 1];
 988         char *c;
 989
 990         if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
 991                 die("Too long path: %.*s", 60, path);
 992
 993         for (c = buf; *c; c++) {
 994                 if (*c == '/')
 995                         *c = '\\';
 996         }
 997         return buf;
 998 }
 999
1000 void mingw_open_html(const char *unixpath)
1001 {
1002         const char *htmlpath = make_backslash_path(unixpath);
1003         printf("Launching default browser to display HTML ...\n");
1004         ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1005 }