compat/mingw.c

   1 #include "../git-compat-util.h"
   2 #include "win32.h"
   3 #include <conio.h>
   4 #include "../strbuf.h"
   5
   6 int err_win_to_posix(DWORD winerr)
   7 {
   8         int error = ENOSYS;
   9         switch(winerr) {
  10         case ERROR_ACCESS_DENIED: error = EACCES; break;
  11         case ERROR_ACCOUNT_DISABLED: error = EACCES; break;
  12         case ERROR_ACCOUNT_RESTRICTION: error = EACCES; break;
  13         case ERROR_ALREADY_ASSIGNED: error = EBUSY; break;
  14         case ERROR_ALREADY_EXISTS: error = EEXIST; break;
  15         case ERROR_ARITHMETIC_OVERFLOW: error = ERANGE; break;
  16         case ERROR_BAD_COMMAND: error = EIO; break;
  17         case ERROR_BAD_DEVICE: error = ENODEV; break;
  18         case ERROR_BAD_DRIVER_LEVEL: error = ENXIO; break;
  19         case ERROR_BAD_EXE_FORMAT: error = ENOEXEC; break;
  20         case ERROR_BAD_FORMAT: error = ENOEXEC; break;
  21         case ERROR_BAD_LENGTH: error = EINVAL; break;
  22         case ERROR_BAD_PATHNAME: error = ENOENT; break;
  23         case ERROR_BAD_PIPE: error = EPIPE; break;
  24         case ERROR_BAD_UNIT: error = ENODEV; break;
  25         case ERROR_BAD_USERNAME: error = EINVAL; break;
  26         case ERROR_BROKEN_PIPE: error = EPIPE; break;
  27         case ERROR_BUFFER_OVERFLOW: error = ENAMETOOLONG; break;
  28         case ERROR_BUSY: error = EBUSY; break;
  29         case ERROR_BUSY_DRIVE: error = EBUSY; break;
  30         case ERROR_CALL_NOT_IMPLEMENTED: error = ENOSYS; break;
  31         case ERROR_CANNOT_MAKE: error = EACCES; break;
  32         case ERROR_CANTOPEN: error = EIO; break;
  33         case ERROR_CANTREAD: error = EIO; break;
  34         case ERROR_CANTWRITE: error = EIO; break;
  35         case ERROR_CRC: error = EIO; break;
  36         case ERROR_CURRENT_DIRECTORY: error = EACCES; break;
  37         case ERROR_DEVICE_IN_USE: error = EBUSY; break;
  38         case ERROR_DEV_NOT_EXIST: error = ENODEV; break;
  39         case ERROR_DIRECTORY: error = EINVAL; break;
  40         case ERROR_DIR_NOT_EMPTY: error = ENOTEMPTY; break;
  41         case ERROR_DISK_CHANGE: error = EIO; break;
  42         case ERROR_DISK_FULL: error = ENOSPC; break;
  43         case ERROR_DRIVE_LOCKED: error = EBUSY; break;
  44         case ERROR_ENVVAR_NOT_FOUND: error = EINVAL; break;
  45         case ERROR_EXE_MARKED_INVALID: error = ENOEXEC; break;
  46         case ERROR_FILENAME_EXCED_RANGE: error = ENAMETOOLONG; break;
  47         case ERROR_FILE_EXISTS: error = EEXIST; break;
  48         case ERROR_FILE_INVALID: error = ENODEV; break;
  49         case ERROR_FILE_NOT_FOUND: error = ENOENT; break;
  50         case ERROR_GEN_FAILURE: error = EIO; break;
  51         case ERROR_HANDLE_DISK_FULL: error = ENOSPC; break;
  52         case ERROR_INSUFFICIENT_BUFFER: error = ENOMEM; break;
  53         case ERROR_INVALID_ACCESS: error = EACCES; break;
  54         case ERROR_INVALID_ADDRESS: error = EFAULT; break;
  55         case ERROR_INVALID_BLOCK: error = EFAULT; break;
  56         case ERROR_INVALID_DATA: error = EINVAL; break;
  57         case ERROR_INVALID_DRIVE: error = ENODEV; break;
  58         case ERROR_INVALID_EXE_SIGNATURE: error = ENOEXEC; break;
  59         case ERROR_INVALID_FLAGS: error = EINVAL; break;
  60         case ERROR_INVALID_FUNCTION: error = ENOSYS; break;
  61         case ERROR_INVALID_HANDLE: error = EBADF; break;
  62         case ERROR_INVALID_LOGON_HOURS: error = EACCES; break;
  63         case ERROR_INVALID_NAME: error = EINVAL; break;
  64         case ERROR_INVALID_OWNER: error = EINVAL; break;
  65         case ERROR_INVALID_PARAMETER: error = EINVAL; break;
  66         case ERROR_INVALID_PASSWORD: error = EPERM; break;
  67         case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
  68         case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
  69         case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
  70         case ERROR_INVALID_WORKSTATION: error = EACCES; break;
  71         case ERROR_IO_DEVICE: error = EIO; break;
  72         case ERROR_IO_INCOMPLETE: error = EINTR; break;
  73         case ERROR_LOCKED: error = EBUSY; break;
  74         case ERROR_LOCK_VIOLATION: error = EACCES; break;
  75         case ERROR_LOGON_FAILURE: error = EACCES; break;
  76         case ERROR_MAPPED_ALIGNMENT: error = EINVAL; break;
  77         case ERROR_META_EXPANSION_TOO_LONG: error = E2BIG; break;
  78         case ERROR_MORE_DATA: error = EPIPE; break;
  79         case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
  80         case ERROR_NOACCESS: error = EFAULT; break;
  81         case ERROR_NONE_MAPPED: error = EINVAL; break;
  82         case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
  83         case ERROR_NOT_READY: error = EAGAIN; break;
  84         case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
  85         case ERROR_NO_DATA: error = EPIPE; break;
  86         case ERROR_NO_MORE_SEARCH_HANDLES: error = EIO; break;
  87         case ERROR_NO_PROC_SLOTS: error = EAGAIN; break;
  88         case ERROR_NO_SUCH_PRIVILEGE: error = EACCES; break;
  89         case ERROR_OPEN_FAILED: error = EIO; break;
  90         case ERROR_OPEN_FILES: error = EBUSY; break;
  91         case ERROR_OPERATION_ABORTED: error = EINTR; break;
  92         case ERROR_OUTOFMEMORY: error = ENOMEM; break;
  93         case ERROR_PASSWORD_EXPIRED: error = EACCES; break;
  94         case ERROR_PATH_BUSY: error = EBUSY; break;
  95         case ERROR_PATH_NOT_FOUND: error = ENOENT; break;
  96         case ERROR_PIPE_BUSY: error = EBUSY; break;
  97         case ERROR_PIPE_CONNECTED: error = EPIPE; break;
  98         case ERROR_PIPE_LISTENING: error = EPIPE; break;
  99         case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 100         case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 101         case ERROR_READ_FAULT: error = EIO; break;
 102         case ERROR_SEEK: error = EIO; break;
 103         case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 104         case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;
 105         case ERROR_SHARING_VIOLATION: error = EACCES; break;
 106         case ERROR_STACK_OVERFLOW: error = ENOMEM; break;
 107         case ERROR_SWAPERROR: error = ENOENT; break;
 108         case ERROR_TOO_MANY_MODULES: error = EMFILE; break;
 109         case ERROR_TOO_MANY_OPEN_FILES: error = EMFILE; break;
 110         case ERROR_UNRECOGNIZED_MEDIA: error = ENXIO; break;
 111         case ERROR_UNRECOGNIZED_VOLUME: error = ENODEV; break;
 112         case ERROR_WAIT_NO_CHILDREN: error = ECHILD; break;
 113         case ERROR_WRITE_FAULT: error = EIO; break;
 114         case ERROR_WRITE_PROTECT: error = EROFS; break;
 115         }
 116         return error;
 117 }
 118
 119 #undef open
 120 int mingw_open (const char *filename, int oflags, ...)
 121 {
 122         va_list args;
 123         unsigned mode;
 124         int fd;
 125
 126         va_start(args, oflags);
 127         mode = va_arg(args, int);
 128         va_end(args);
 129
 130         if (!strcmp(filename, "/dev/null"))
 131                 filename = "nul";
 132
 133         fd = open(filename, oflags, mode);
 134
 135         if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
 136                 DWORD attrs = GetFileAttributes(filename);
 137                 if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
 138                         errno = EISDIR;
 139         }
 140         return fd;
 141 }
 142
 143 #undef write
 144 ssize_t mingw_write(int fd, const void *buf, size_t count)
 145 {
 146         /*
 147          * While write() calls to a file on a local disk are translated
 148          * into WriteFile() calls with a maximum size of 64KB on Windows
 149          * XP and 256KB on Vista, no such cap is placed on writes to
 150          * files over the network on Windows XP.  Unfortunately, there
 151          * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86;
 152          * bigger writes fail on Windows XP.
 153          * So we cap to a nice 31MB here to avoid write failures over
 154          * the net without changing the number of WriteFile() calls in
 155          * the local case.
 156          */
 157         return write(fd, buf, min(count, 31 * 1024 * 1024));
 158 }
 159
 160 #undef fopen
 161 FILE *mingw_fopen (const char *filename, const char *otype)
 162 {
 163         if (!strcmp(filename, "/dev/null"))
 164                 filename = "nul";
 165         return fopen(filename, otype);
 166 }
 167
 168 #undef freopen
 169 FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 170 {
 171         if (filename && !strcmp(filename, "/dev/null"))
 172                 filename = "nul";
 173         return freopen(filename, otype, stream);
 174 }
 175
 176 /*
 177  * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
 178  * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
 179  */
 180 static inline long long filetime_to_hnsec(const FILETIME *ft)
 181 {
 182         long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 183         /* Windows to Unix Epoch conversion */
 184         return winTime - 116444736000000000LL;
 185 }
 186
 187 static inline time_t filetime_to_time_t(const FILETIME *ft)
 188 {
 189         return (time_t)(filetime_to_hnsec(ft) / 10000000);
 190 }
 191
 192 /* We keep the do_lstat code in a separate function to avoid recursion.
 193  * When a path ends with a slash, the stat will fail with ENOENT. In
 194  * this case, we strip the trailing slashes and stat again.
 195  */
 196 static int do_lstat(const char *file_name, struct stat *buf)
 197 {
 198         WIN32_FILE_ATTRIBUTE_DATA fdata;
 199
 200         if (!(errno = get_file_attr(file_name, &fdata))) {
 201                 buf->st_ino = 0;
 202                 buf->st_gid = 0;
 203                 buf->st_uid = 0;
 204                 buf->st_nlink = 1;
 205                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 206                 buf->st_size = fdata.nFileSizeLow |
 207                         (((off_t)fdata.nFileSizeHigh)<<32);
 208                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 209                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 210                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 211                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 212                 return 0;
 213         }
 214         return -1;
 215 }
 216
 217 /* We provide our own lstat/fstat functions, since the provided
 218  * lstat/fstat functions are so slow. These stat functions are
 219  * tailored for Git's usage (read: fast), and are not meant to be
 220  * complete. Note that Git stat()s are redirected to mingw_lstat()
 221  * too, since Windows doesn't really handle symlinks that well.
 222  */
 223 int mingw_lstat(const char *file_name, struct stat *buf)
 224 {
 225         int namelen;
 226         static char alt_name[PATH_MAX];
 227
 228         if (!do_lstat(file_name, buf))
 229                 return 0;
 230
 231         /* if file_name ended in a '/', Windows returned ENOENT;
 232          * try again without trailing slashes
 233          */
 234         if (errno != ENOENT)
 235                 return -1;
 236
 237         namelen = strlen(file_name);
 238         if (namelen && file_name[namelen-1] != '/')
 239                 return -1;
 240         while (namelen && file_name[namelen-1] == '/')
 241                 --namelen;
 242         if (!namelen || namelen >= PATH_MAX)
 243                 return -1;
 244
 245         memcpy(alt_name, file_name, namelen);
 246         alt_name[namelen] = 0;
 247         return do_lstat(alt_name, buf);
 248 }
 249
 250 #undef fstat
 251 int mingw_fstat(int fd, struct stat *buf)
 252 {
 253         HANDLE fh = (HANDLE)_get_osfhandle(fd);
 254         BY_HANDLE_FILE_INFORMATION fdata;
 255
 256         if (fh == INVALID_HANDLE_VALUE) {
 257                 errno = EBADF;
 258                 return -1;
 259         }
 260         /* direct non-file handles to MS's fstat() */
 261         if (GetFileType(fh) != FILE_TYPE_DISK)
 262                 return _fstati64(fd, buf);
 263
 264         if (GetFileInformationByHandle(fh, &fdata)) {
 265                 buf->st_ino = 0;
 266                 buf->st_gid = 0;
 267                 buf->st_uid = 0;
 268                 buf->st_nlink = 1;
 269                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 270                 buf->st_size = fdata.nFileSizeLow |
 271                         (((off_t)fdata.nFileSizeHigh)<<32);
 272                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 273                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 274                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 275                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 276                 return 0;
 277         }
 278         errno = EBADF;
 279         return -1;
 280 }
 281
 282 static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 283 {
 284         long long winTime = t * 10000000LL + 116444736000000000LL;
 285         ft->dwLowDateTime = winTime;
 286         ft->dwHighDateTime = winTime >> 32;
 287 }
 288
 289 int mingw_utime (const char *file_name, const struct utimbuf *times)
 290 {
 291         FILETIME mft, aft;
 292         int fh, rc;
 293
 294         /* must have write permission */
 295         DWORD attrs = GetFileAttributes(file_name);
 296         if (attrs != INVALID_FILE_ATTRIBUTES &&
 297             (attrs & FILE_ATTRIBUTE_READONLY)) {
 298                 /* ignore errors here; open() will report them */
 299                 SetFileAttributes(file_name, attrs & ~FILE_ATTRIBUTE_READONLY);
 300         }
 301
 302         if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0) {
 303                 rc = -1;
 304                 goto revert_attrs;
 305         }
 306
 307         time_t_to_filetime(times->modtime, &mft);
 308         time_t_to_filetime(times->actime, &aft);
 309         if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 310                 errno = EINVAL;
 311                 rc = -1;
 312         } else
 313                 rc = 0;
 314         close(fh);
 315
 316 revert_attrs:
 317         if (attrs != INVALID_FILE_ATTRIBUTES &&
 318             (attrs & FILE_ATTRIBUTE_READONLY)) {
 319                 /* ignore errors again */
 320                 SetFileAttributes(file_name, attrs);
 321         }
 322         return rc;
 323 }
 324
 325 unsigned int sleep (unsigned int seconds)
 326 {
 327         Sleep(seconds*1000);
 328         return 0;
 329 }
 330
 331 int mkstemp(char *template)
 332 {
 333         char *filename = mktemp(template);
 334         if (filename == NULL)
 335                 return -1;
 336         return open(filename, O_RDWR | O_CREAT, 0600);
 337 }
 338
 339 int gettimeofday(struct timeval *tv, void *tz)
 340 {
 341         FILETIME ft;
 342         long long hnsec;
 343
 344         GetSystemTimeAsFileTime(&ft);
 345         hnsec = filetime_to_hnsec(&ft);
 346         tv->tv_sec = hnsec / 10000000;
 347         tv->tv_usec = (hnsec % 10000000) / 10;
 348         return 0;
 349 }
 350
 351 int pipe(int filedes[2])
 352 {
 353         HANDLE h[2];
 354
 355         /* this creates non-inheritable handles */
 356         if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
 357                 errno = err_win_to_posix(GetLastError());
 358                 return -1;
 359         }
 360         filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
 361         if (filedes[0] < 0) {
 362                 CloseHandle(h[0]);
 363                 CloseHandle(h[1]);
 364                 return -1;
 365         }
 366         filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
 367         if (filedes[0] < 0) {
 368                 close(filedes[0]);
 369                 CloseHandle(h[1]);
 370                 return -1;
 371         }
 372         return 0;
 373 }
 374
 375 int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 376 {
 377         int i, pending;
 378
 379         if (timeout >= 0) {
 380                 if (nfds == 0) {
 381                         Sleep(timeout);
 382                         return 0;
 383                 }
 384                 return errno = EINVAL, error("poll timeout not supported");
 385         }
 386
 387         /* When there is only one fd to wait for, then we pretend that
 388          * input is available and let the actual wait happen when the
 389          * caller invokes read().
 390          */
 391         if (nfds == 1) {
 392                 if (!(ufds[0].events & POLLIN))
 393                         return errno = EINVAL, error("POLLIN not set");
 394                 ufds[0].revents = POLLIN;
 395                 return 0;
 396         }
 397
 398 repeat:
 399         pending = 0;
 400         for (i = 0; i < nfds; i++) {
 401                 DWORD avail = 0;
 402                 HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 403                 if (h == INVALID_HANDLE_VALUE)
 404                         return -1;      /* errno was set */
 405
 406                 if (!(ufds[i].events & POLLIN))
 407                         return errno = EINVAL, error("POLLIN not set");
 408
 409                 /* this emulation works only for pipes */
 410                 if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 411                         int err = GetLastError();
 412                         if (err == ERROR_BROKEN_PIPE) {
 413                                 ufds[i].revents = POLLHUP;
 414                                 pending++;
 415                         } else {
 416                                 errno = EINVAL;
 417                                 return error("PeekNamedPipe failed,"
 418                                         " GetLastError: %u", err);
 419                         }
 420                 } else if (avail) {
 421                         ufds[i].revents = POLLIN;
 422                         pending++;
 423                 } else
 424                         ufds[i].revents = 0;
 425         }
 426         if (!pending) {
 427                 /* The only times that we spin here is when the process
 428                  * that is connected through the pipes is waiting for
 429                  * its own input data to become available. But since
 430                  * the process (pack-objects) is itself CPU intensive,
 431                  * it will happily pick up the time slice that we are
 432                  * relinquishing here.
 433                  */
 434                 Sleep(0);
 435                 goto repeat;
 436         }
 437         return 0;
 438 }
 439
 440 struct tm *gmtime_r(const time_t *timep, struct tm *result)
 441 {
 442         /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 443         memcpy(result, gmtime(timep), sizeof(struct tm));
 444         return result;
 445 }
 446
 447 struct tm *localtime_r(const time_t *timep, struct tm *result)
 448 {
 449         /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 450         memcpy(result, localtime(timep), sizeof(struct tm));
 451         return result;
 452 }
 453
 454 #undef getcwd
 455 char *mingw_getcwd(char *pointer, int len)
 456 {
 457         int i;
 458         char *ret = getcwd(pointer, len);
 459         if (!ret)
 460                 return ret;
 461         for (i = 0; pointer[i]; i++)
 462                 if (pointer[i] == '\\')
 463                         pointer[i] = '/';
 464         return ret;
 465 }
 466
 467 #undef getenv
 468 char *mingw_getenv(const char *name)
 469 {
 470         char *result = getenv(name);
 471         if (!result && !strcmp(name, "TMPDIR")) {
 472                 /* on Windows it is TMP and TEMP */
 473                 result = getenv("TMP");
 474                 if (!result)
 475                         result = getenv("TEMP");
 476         }
 477         return result;
 478 }
 479
 480 /*
 481  * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 482  * (Parsing C++ Command-Line Arguments)
 483  */
 484 static const char *quote_arg(const char *arg)
 485 {
 486         /* count chars to quote */
 487         int len = 0, n = 0;
 488         int force_quotes = 0;
 489         char *q, *d;
 490         const char *p = arg;
 491         if (!*p) force_quotes = 1;
 492         while (*p) {
 493                 if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 494                         force_quotes = 1;
 495                 else if (*p == '"')
 496                         n++;
 497                 else if (*p == '\\') {
 498                         int count = 0;
 499                         while (*p == '\\') {
 500                                 count++;
 501                                 p++;
 502                                 len++;
 503                         }
 504                         if (*p == '"')
 505                                 n += count*2 + 1;
 506                         continue;
 507                 }
 508                 len++;
 509                 p++;
 510         }
 511         if (!force_quotes && n == 0)
 512                 return arg;
 513
 514         /* insert \ where necessary */
 515         d = q = xmalloc(len+n+3);
 516         *d++ = '"';
 517         while (*arg) {
 518                 if (*arg == '"')
 519                         *d++ = '\\';
 520                 else if (*arg == '\\') {
 521                         int count = 0;
 522                         while (*arg == '\\') {
 523                                 count++;
 524                                 *d++ = *arg++;
 525                         }
 526                         if (*arg == '"') {
 527                                 while (count-- > 0)
 528                                         *d++ = '\\';
 529                                 *d++ = '\\';
 530                         }
 531                 }
 532                 *d++ = *arg++;
 533         }
 534         *d++ = '"';
 535         *d++ = 0;
 536         return q;
 537 }
 538
 539 static const char *parse_interpreter(const char *cmd)
 540 {
 541         static char buf[100];
 542         char *p, *opt;
 543         int n, fd;
 544
 545         /* don't even try a .exe */
 546         n = strlen(cmd);
 547         if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 548                 return NULL;
 549
 550         fd = open(cmd, O_RDONLY);
 551         if (fd < 0)
 552                 return NULL;
 553         n = read(fd, buf, sizeof(buf)-1);
 554         close(fd);
 555         if (n < 4)      /* at least '#!/x' and not error */
 556                 return NULL;
 557
 558         if (buf[0] != '#' || buf[1] != '!')
 559                 return NULL;
 560         buf[n] = '\0';
 561         p = buf + strcspn(buf, "\r\n");
 562         if (!*p)
 563                 return NULL;
 564
 565         *p = '\0';
 566         if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 567                 return NULL;
 568         /* strip options */
 569         if ((opt = strchr(p+1, ' ')))
 570                 *opt = '\0';
 571         return p+1;
 572 }
 573
 574 /*
 575  * Splits the PATH into parts.
 576  */
 577 static char **get_path_split(void)
 578 {
 579         char *p, **path, *envpath = getenv("PATH");
 580         int i, n = 0;
 581
 582         if (!envpath || !*envpath)
 583                 return NULL;
 584
 585         envpath = xstrdup(envpath);
 586         p = envpath;
 587         while (p) {
 588                 char *dir = p;
 589                 p = strchr(p, ';');
 590                 if (p) *p++ = '\0';
 591                 if (*dir) {     /* not earlier, catches series of ; */
 592                         ++n;
 593                 }
 594         }
 595         if (!n)
 596                 return NULL;
 597
 598         path = xmalloc((n+1)*sizeof(char *));
 599         p = envpath;
 600         i = 0;
 601         do {
 602                 if (*p)
 603                         path[i++] = xstrdup(p);
 604                 p = p+strlen(p)+1;
 605         } while (i < n);
 606         path[i] = NULL;
 607
 608         free(envpath);
 609
 610         return path;
 611 }
 612
 613 static void free_path_split(char **path)
 614 {
 615         char **p = path;
 616
 617         if (!path)
 618                 return;
 619
 620         while (*p)
 621                 free(*p++);
 622         free(path);
 623 }
 624
 625 /*
 626  * exe_only means that we only want to detect .exe files, but not scripts
 627  * (which do not have an extension)
 628  */
 629 static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 630 {
 631         char path[MAX_PATH];
 632         snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 633
 634         if (!isexe && access(path, F_OK) == 0)
 635                 return xstrdup(path);
 636         path[strlen(path)-4] = '\0';
 637         if ((!exe_only || isexe) && access(path, F_OK) == 0)
 638                 if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 639                         return xstrdup(path);
 640         return NULL;
 641 }
 642
 643 /*
 644  * Determines the absolute path of cmd using the split path in path.
 645  * If cmd contains a slash or backslash, no lookup is performed.
 646  */
 647 static char *path_lookup(const char *cmd, char **path, int exe_only)
 648 {
 649         char *prog = NULL;
 650         int len = strlen(cmd);
 651         int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 652
 653         if (strchr(cmd, '/') || strchr(cmd, '\\'))
 654                 prog = xstrdup(cmd);
 655
 656         while (!prog && *path)
 657                 prog = lookup_prog(*path++, cmd, isexe, exe_only);
 658
 659         return prog;
 660 }
 661
 662 static int env_compare(const void *a, const void *b)
 663 {
 664         char *const *ea = a;
 665         char *const *eb = b;
 666         return strcasecmp(*ea, *eb);
 667 }
 668
 669 static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
 670                               const char *dir,
 671                               int prepend_cmd, int fhin, int fhout, int fherr)
 672 {
 673         STARTUPINFO si;
 674         PROCESS_INFORMATION pi;
 675         struct strbuf envblk, args;
 676         unsigned flags;
 677         BOOL ret;
 678
 679         /* Determine whether or not we are associated to a console */
 680         HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 681                         FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 682                         FILE_ATTRIBUTE_NORMAL, NULL);
 683         if (cons == INVALID_HANDLE_VALUE) {
 684                 /* There is no console associated with this process.
 685                  * Since the child is a console process, Windows
 686                  * would normally create a console window. But
 687                  * since we'll be redirecting std streams, we do
 688                  * not need the console.
 689                  * It is necessary to use DETACHED_PROCESS
 690                  * instead of CREATE_NO_WINDOW to make ssh
 691                  * recognize that it has no console.
 692                  */
 693                 flags = DETACHED_PROCESS;
 694         } else {
 695                 /* There is already a console. If we specified
 696                  * DETACHED_PROCESS here, too, Windows would
 697                  * disassociate the child from the console.
 698                  * The same is true for CREATE_NO_WINDOW.
 699                  * Go figure!
 700                  */
 701                 flags = 0;
 702                 CloseHandle(cons);
 703         }
 704         memset(&si, 0, sizeof(si));
 705         si.cb = sizeof(si);
 706         si.dwFlags = STARTF_USESTDHANDLES;
 707         si.hStdInput = (HANDLE) _get_osfhandle(fhin);
 708         si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
 709         si.hStdError = (HANDLE) _get_osfhandle(fherr);
 710
 711         /* concatenate argv, quoting args as we go */
 712         strbuf_init(&args, 0);
 713         if (prepend_cmd) {
 714                 char *quoted = (char *)quote_arg(cmd);
 715                 strbuf_addstr(&args, quoted);
 716                 if (quoted != cmd)
 717                         free(quoted);
 718         }
 719         for (; *argv; argv++) {
 720                 char *quoted = (char *)quote_arg(*argv);
 721                 if (*args.buf)
 722                         strbuf_addch(&args, ' ');
 723                 strbuf_addstr(&args, quoted);
 724                 if (quoted != *argv)
 725                         free(quoted);
 726         }
 727
 728         if (env) {
 729                 int count = 0;
 730                 char **e, **sorted_env;
 731
 732                 for (e = env; *e; e++)
 733                         count++;
 734
 735                 /* environment must be sorted */
 736                 sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 737                 memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 738                 qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 739
 740                 strbuf_init(&envblk, 0);
 741                 for (e = sorted_env; *e; e++) {
 742                         strbuf_addstr(&envblk, *e);
 743                         strbuf_addch(&envblk, '\0');
 744                 }
 745                 free(sorted_env);
 746         }
 747
 748         memset(&pi, 0, sizeof(pi));
 749         ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 750                 env ? envblk.buf : NULL, dir, &si, &pi);
 751
 752         if (env)
 753                 strbuf_release(&envblk);
 754         strbuf_release(&args);
 755
 756         if (!ret) {
 757                 errno = ENOENT;
 758                 return -1;
 759         }
 760         CloseHandle(pi.hThread);
 761         return (pid_t)pi.hProcess;
 762 }
 763
 764 static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 765                            int prepend_cmd)
 766 {
 767         return mingw_spawnve_fd(cmd, argv, env, NULL, prepend_cmd, 0, 1, 2);
 768 }
 769
 770 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
 771                      const char *dir,
 772                      int fhin, int fhout, int fherr)
 773 {
 774         pid_t pid;
 775         char **path = get_path_split();
 776         char *prog = path_lookup(cmd, path, 0);
 777
 778         if (!prog) {
 779                 errno = ENOENT;
 780                 pid = -1;
 781         }
 782         else {
 783                 const char *interpr = parse_interpreter(prog);
 784
 785                 if (interpr) {
 786                         const char *argv0 = argv[0];
 787                         char *iprog = path_lookup(interpr, path, 1);
 788                         argv[0] = prog;
 789                         if (!iprog) {
 790                                 errno = ENOENT;
 791                                 pid = -1;
 792                         }
 793                         else {
 794                                 pid = mingw_spawnve_fd(iprog, argv, env, dir, 1,
 795                                                        fhin, fhout, fherr);
 796                                 free(iprog);
 797                         }
 798                         argv[0] = argv0;
 799                 }
 800                 else
 801                         pid = mingw_spawnve_fd(prog, argv, env, dir, 0,
 802                                                fhin, fhout, fherr);
 803                 free(prog);
 804         }
 805         free_path_split(path);
 806         return pid;
 807 }
 808
 809 static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 810 {
 811         const char *interpr = parse_interpreter(cmd);
 812         char **path;
 813         char *prog;
 814         int pid = 0;
 815
 816         if (!interpr)
 817                 return 0;
 818         path = get_path_split();
 819         prog = path_lookup(interpr, path, 1);
 820         if (prog) {
 821                 int argc = 0;
 822                 const char **argv2;
 823                 while (argv[argc]) argc++;
 824                 argv2 = xmalloc(sizeof(*argv) * (argc+1));
 825                 argv2[0] = (char *)cmd; /* full path to the script file */
 826                 memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 827                 pid = mingw_spawnve(prog, argv2, env, 1);
 828                 if (pid >= 0) {
 829                         int status;
 830                         if (waitpid(pid, &status, 0) < 0)
 831                                 status = 255;
 832                         exit(status);
 833                 }
 834                 pid = 1;        /* indicate that we tried but failed */
 835                 free(prog);
 836                 free(argv2);
 837         }
 838         free_path_split(path);
 839         return pid;
 840 }
 841
 842 static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 843 {
 844         /* check if git_command is a shell script */
 845         if (!try_shell_exec(cmd, argv, (char **)env)) {
 846                 int pid, status;
 847
 848                 pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 849                 if (pid < 0)
 850                         return;
 851                 if (waitpid(pid, &status, 0) < 0)
 852                         status = 255;
 853                 exit(status);
 854         }
 855 }
 856
 857 void mingw_execvp(const char *cmd, char *const *argv)
 858 {
 859         char **path = get_path_split();
 860         char *prog = path_lookup(cmd, path, 0);
 861
 862         if (prog) {
 863                 mingw_execve(prog, argv, environ);
 864                 free(prog);
 865         } else
 866                 errno = ENOENT;
 867
 868         free_path_split(path);
 869 }
 870
 871 static char **copy_environ(void)
 872 {
 873         char **env;
 874         int i = 0;
 875         while (environ[i])
 876                 i++;
 877         env = xmalloc((i+1)*sizeof(*env));
 878         for (i = 0; environ[i]; i++)
 879                 env[i] = xstrdup(environ[i]);
 880         env[i] = NULL;
 881         return env;
 882 }
 883
 884 void free_environ(char **env)
 885 {
 886         int i;
 887         for (i = 0; env[i]; i++)
 888                 free(env[i]);
 889         free(env);
 890 }
 891
 892 static int lookup_env(char **env, const char *name, size_t nmln)
 893 {
 894         int i;
 895
 896         for (i = 0; env[i]; i++) {
 897                 if (0 == strncmp(env[i], name, nmln)
 898                     && '=' == env[i][nmln])
 899                         /* matches */
 900                         return i;
 901         }
 902         return -1;
 903 }
 904
 905 /*
 906  * If name contains '=', then sets the variable, otherwise it unsets it
 907  */
 908 static char **env_setenv(char **env, const char *name)
 909 {
 910         char *eq = strchrnul(name, '=');
 911         int i = lookup_env(env, name, eq-name);
 912
 913         if (i < 0) {
 914                 if (*eq) {
 915                         for (i = 0; env[i]; i++)
 916                                 ;
 917                         env = xrealloc(env, (i+2)*sizeof(*env));
 918                         env[i] = xstrdup(name);
 919                         env[i+1] = NULL;
 920                 }
 921         }
 922         else {
 923                 free(env[i]);
 924                 if (*eq)
 925                         env[i] = xstrdup(name);
 926                 else
 927                         for (; env[i]; i++)
 928                                 env[i] = env[i+1];
 929         }
 930         return env;
 931 }
 932
 933 /*
 934  * Copies global environ and adjusts variables as specified by vars.
 935  */
 936 char **make_augmented_environ(const char *const *vars)
 937 {
 938         char **env = copy_environ();
 939
 940         while (*vars)
 941                 env = env_setenv(env, *vars++);
 942         return env;
 943 }
 944
 945 /*
 946  * Note, this isn't a complete replacement for getaddrinfo. It assumes
 947  * that service contains a numerical port, or that it it is null. It
 948  * does a simple search using gethostbyname, and returns one IPv4 host
 949  * if one was found.
 950  */
 951 static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
 952                                    const struct addrinfo *hints,
 953                                    struct addrinfo **res)
 954 {
 955         struct hostent *h = gethostbyname(node);
 956         struct addrinfo *ai;
 957         struct sockaddr_in *sin;
 958
 959         if (!h)
 960                 return WSAGetLastError();
 961
 962         ai = xmalloc(sizeof(struct addrinfo));
 963         *res = ai;
 964         ai->ai_flags = 0;
 965         ai->ai_family = AF_INET;
 966         ai->ai_socktype = hints->ai_socktype;
 967         switch (hints->ai_socktype) {
 968         case SOCK_STREAM:
 969                 ai->ai_protocol = IPPROTO_TCP;
 970                 break;
 971         case SOCK_DGRAM:
 972                 ai->ai_protocol = IPPROTO_UDP;
 973                 break;
 974         default:
 975                 ai->ai_protocol = 0;
 976                 break;
 977         }
 978         ai->ai_addrlen = sizeof(struct sockaddr_in);
 979         ai->ai_canonname = strdup(h->h_name);
 980
 981         sin = xmalloc(ai->ai_addrlen);
 982         memset(sin, 0, ai->ai_addrlen);
 983         sin->sin_family = AF_INET;
 984         if (service)
 985                 sin->sin_port = htons(atoi(service));
 986         sin->sin_addr = *(struct in_addr *)h->h_addr;
 987         ai->ai_addr = (struct sockaddr *)sin;
 988         ai->ai_next = 0;
 989         return 0;
 990 }
 991
 992 static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
 993 {
 994         free(res->ai_canonname);
 995         free(res->ai_addr);
 996         free(res);
 997 }
 998
 999 static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
1000                                    char *host, DWORD hostlen,
1001                                    char *serv, DWORD servlen, int flags)
1002 {
1003         const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
1004         if (sa->sa_family != AF_INET)
1005                 return EAI_FAMILY;
1006         if (!host && !serv)
1007                 return EAI_NONAME;
1008
1009         if (host && hostlen > 0) {
1010                 struct hostent *ent = NULL;
1011                 if (!(flags & NI_NUMERICHOST))
1012                         ent = gethostbyaddr((const char *)&sin->sin_addr,
1013                                             sizeof(sin->sin_addr), AF_INET);
1014
1015                 if (ent)
1016                         snprintf(host, hostlen, "%s", ent->h_name);
1017                 else if (flags & NI_NAMEREQD)
1018                         return EAI_NONAME;
1019                 else
1020                         snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
1021         }
1022
1023         if (serv && servlen > 0) {
1024                 struct servent *ent = NULL;
1025                 if (!(flags & NI_NUMERICSERV))
1026                         ent = getservbyport(sin->sin_port,
1027                                             flags & NI_DGRAM ? "udp" : "tcp");
1028
1029                 if (ent)
1030                         snprintf(serv, servlen, "%s", ent->s_name);
1031                 else
1032                         snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
1033         }
1034
1035         return 0;
1036 }
1037
1038 static HMODULE ipv6_dll = NULL;
1039 static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
1040 static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
1041                                       const struct addrinfo *hints,
1042                                       struct addrinfo **res);
1043 static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
1044                                       char *host, DWORD hostlen,
1045                                       char *serv, DWORD servlen, int flags);
1046 /*
1047  * gai_strerror is an inline function in the ws2tcpip.h header, so we
1048  * don't need to try to load that one dynamically.
1049  */
1050
1051 static void socket_cleanup(void)
1052 {
1053         WSACleanup();
1054         if (ipv6_dll)
1055                 FreeLibrary(ipv6_dll);
1056         ipv6_dll = NULL;
1057         ipv6_freeaddrinfo = freeaddrinfo_stub;
1058         ipv6_getaddrinfo = getaddrinfo_stub;
1059         ipv6_getnameinfo = getnameinfo_stub;
1060 }
1061
1062 static void ensure_socket_initialization(void)
1063 {
1064         WSADATA wsa;
1065         static int initialized = 0;
1066         const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
1067         const char **name;
1068
1069         if (initialized)
1070                 return;
1071
1072         if (WSAStartup(MAKEWORD(2,2), &wsa))
1073                 die("unable to initialize winsock subsystem, error %d",
1074                         WSAGetLastError());
1075
1076         for (name = libraries; *name; name++) {
1077                 ipv6_dll = LoadLibrary(*name);
1078                 if (!ipv6_dll)
1079                         continue;
1080
1081                 ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
1082                         GetProcAddress(ipv6_dll, "freeaddrinfo");
1083                 ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
1084                                                    const struct addrinfo *,
1085                                                    struct addrinfo **))
1086                         GetProcAddress(ipv6_dll, "getaddrinfo");
1087                 ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
1088                                                    socklen_t, char *, DWORD,
1089                                                    char *, DWORD, int))
1090                         GetProcAddress(ipv6_dll, "getnameinfo");
1091                 if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1092                         FreeLibrary(ipv6_dll);
1093                         ipv6_dll = NULL;
1094                 } else
1095                         break;
1096         }
1097         if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1098                 ipv6_freeaddrinfo = freeaddrinfo_stub;
1099                 ipv6_getaddrinfo = getaddrinfo_stub;
1100                 ipv6_getnameinfo = getnameinfo_stub;
1101         }
1102
1103         atexit(socket_cleanup);
1104         initialized = 1;
1105 }
1106
1107 #undef gethostbyname
1108 struct hostent *mingw_gethostbyname(const char *host)
1109 {
1110         ensure_socket_initialization();
1111         return gethostbyname(host);
1112 }
1113
1114 void mingw_freeaddrinfo(struct addrinfo *res)
1115 {
1116         ipv6_freeaddrinfo(res);
1117 }
1118
1119 int mingw_getaddrinfo(const char *node, const char *service,
1120                       const struct addrinfo *hints, struct addrinfo **res)
1121 {
1122         ensure_socket_initialization();
1123         return ipv6_getaddrinfo(node, service, hints, res);
1124 }
1125
1126 int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
1127                       char *host, DWORD hostlen, char *serv, DWORD servlen,
1128                       int flags)
1129 {
1130         ensure_socket_initialization();
1131         return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
1132 }
1133
1134 int mingw_socket(int domain, int type, int protocol)
1135 {
1136         int sockfd;
1137         SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
1138         if (s == INVALID_SOCKET) {
1139                 /*
1140                  * WSAGetLastError() values are regular BSD error codes
1141                  * biased by WSABASEERR.
1142                  * However, strerror() does not know about networking
1143                  * specific errors, which are values beginning at 38 or so.
1144                  * Therefore, we choose to leave the biased error code
1145                  * in errno so that _if_ someone looks up the code somewhere,
1146                  * then it is at least the number that are usually listed.
1147                  */
1148                 errno = WSAGetLastError();
1149                 return -1;
1150         }
1151         /* convert into a file descriptor */
1152         if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
1153                 closesocket(s);
1154                 return error("unable to make a socket file descriptor: %s",
1155                         strerror(errno));
1156         }
1157         return sockfd;
1158 }
1159
1160 #undef connect
1161 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1162 {
1163         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1164         return connect(s, sa, sz);
1165 }
1166
1167 #undef rename
1168 int mingw_rename(const char *pold, const char *pnew)
1169 {
1170         DWORD attrs, gle;
1171         int tries = 0;
1172         static const int delay[] = { 0, 1, 10, 20, 40 };
1173
1174         /*
1175          * Try native rename() first to get errno right.
1176          * It is based on MoveFile(), which cannot overwrite existing files.
1177          */
1178         if (!rename(pold, pnew))
1179                 return 0;
1180         if (errno != EEXIST)
1181                 return -1;
1182 repeat:
1183         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1184                 return 0;
1185         /* TODO: translate more errors */
1186         gle = GetLastError();
1187         if (gle == ERROR_ACCESS_DENIED &&
1188             (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1189                 if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1190                         errno = EISDIR;
1191                         return -1;
1192                 }
1193                 if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1194                     SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1195                         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1196                                 return 0;
1197                         gle = GetLastError();
1198                         /* revert file attributes on failure */
1199                         SetFileAttributes(pnew, attrs);
1200                 }
1201         }
1202         if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1203                 /*
1204                  * We assume that some other process had the source or
1205                  * destination file open at the wrong moment and retry.
1206                  * In order to give the other process a higher chance to
1207                  * complete its operation, we give up our time slice now.
1208                  * If we have to retry again, we do sleep a bit.
1209                  */
1210                 Sleep(delay[tries]);
1211                 tries++;
1212                 goto repeat;
1213         }
1214         errno = EACCES;
1215         return -1;
1216 }
1217
1218 /*
1219  * Note that this doesn't return the actual pagesize, but
1220  * the allocation granularity. If future Windows specific git code
1221  * needs the real getpagesize function, we need to find another solution.
1222  */
1223 int mingw_getpagesize(void)
1224 {
1225         SYSTEM_INFO si;
1226         GetSystemInfo(&si);
1227         return si.dwAllocationGranularity;
1228 }
1229
1230 struct passwd *getpwuid(int uid)
1231 {
1232         static char user_name[100];
1233         static struct passwd p;
1234
1235         DWORD len = sizeof(user_name);
1236         if (!GetUserName(user_name, &len))
1237                 return NULL;
1238         p.pw_name = user_name;
1239         p.pw_gecos = "unknown";
1240         p.pw_dir = NULL;
1241         return &p;
1242 }
1243
1244 static HANDLE timer_event;
1245 static HANDLE timer_thread;
1246 static int timer_interval;
1247 static int one_shot;
1248 static sig_handler_t timer_fn = SIG_DFL;
1249
1250 /* The timer works like this:
1251  * The thread, ticktack(), is a trivial routine that most of the time
1252  * only waits to receive the signal to terminate. The main thread tells
1253  * the thread to terminate by setting the timer_event to the signalled
1254  * state.
1255  * But ticktack() interrupts the wait state after the timer's interval
1256  * length to call the signal handler.
1257  */
1258
1259 static unsigned __stdcall ticktack(void *dummy)
1260 {
1261         while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1262                 if (timer_fn == SIG_DFL)
1263                         die("Alarm");
1264                 if (timer_fn != SIG_IGN)
1265                         timer_fn(SIGALRM);
1266                 if (one_shot)
1267                         break;
1268         }
1269         return 0;
1270 }
1271
1272 static int start_timer_thread(void)
1273 {
1274         timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1275         if (timer_event) {
1276                 timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1277                 if (!timer_thread )
1278                         return errno = ENOMEM,
1279                                 error("cannot start timer thread");
1280         } else
1281                 return errno = ENOMEM,
1282                         error("cannot allocate resources for timer");
1283         return 0;
1284 }
1285
1286 static void stop_timer_thread(void)
1287 {
1288         if (timer_event)
1289                 SetEvent(timer_event);  /* tell thread to terminate */
1290         if (timer_thread) {
1291                 int rc = WaitForSingleObject(timer_thread, 1000);
1292                 if (rc == WAIT_TIMEOUT)
1293                         error("timer thread did not terminate timely");
1294                 else if (rc != WAIT_OBJECT_0)
1295                         error("waiting for timer thread failed: %lu",
1296                               GetLastError());
1297                 CloseHandle(timer_thread);
1298         }
1299         if (timer_event)
1300                 CloseHandle(timer_event);
1301         timer_event = NULL;
1302         timer_thread = NULL;
1303 }
1304
1305 static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1306 {
1307         return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1308 }
1309
1310 int setitimer(int type, struct itimerval *in, struct itimerval *out)
1311 {
1312         static const struct timeval zero;
1313         static int atexit_done;
1314
1315         if (out != NULL)
1316                 return errno = EINVAL,
1317                         error("setitimer param 3 != NULL not implemented");
1318         if (!is_timeval_eq(&in->it_interval, &zero) &&
1319             !is_timeval_eq(&in->it_interval, &in->it_value))
1320                 return errno = EINVAL,
1321                         error("setitimer: it_interval must be zero or eq it_value");
1322
1323         if (timer_thread)
1324                 stop_timer_thread();
1325
1326         if (is_timeval_eq(&in->it_value, &zero) &&
1327             is_timeval_eq(&in->it_interval, &zero))
1328                 return 0;
1329
1330         timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1331         one_shot = is_timeval_eq(&in->it_interval, &zero);
1332         if (!atexit_done) {
1333                 atexit(stop_timer_thread);
1334                 atexit_done = 1;
1335         }
1336         return start_timer_thread();
1337 }
1338
1339 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1340 {
1341         if (sig != SIGALRM)
1342                 return errno = EINVAL,
1343                         error("sigaction only implemented for SIGALRM");
1344         if (out != NULL)
1345                 return errno = EINVAL,
1346                         error("sigaction: param 3 != NULL not implemented");
1347
1348         timer_fn = in->sa_handler;
1349         return 0;
1350 }
1351
1352 #undef signal
1353 sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1354 {
1355         sig_handler_t old = timer_fn;
1356         if (sig != SIGALRM)
1357                 return signal(sig, handler);
1358         timer_fn = handler;
1359         return old;
1360 }
1361
1362 static const char *make_backslash_path(const char *path)
1363 {
1364         static char buf[PATH_MAX + 1];
1365         char *c;
1366
1367         if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1368                 die("Too long path: %.*s", 60, path);
1369
1370         for (c = buf; *c; c++) {
1371                 if (*c == '/')
1372                         *c = '\\';
1373         }
1374         return buf;
1375 }
1376
1377 void mingw_open_html(const char *unixpath)
1378 {
1379         const char *htmlpath = make_backslash_path(unixpath);
1380         typedef HINSTANCE (WINAPI *T)(HWND, const char *,
1381                         const char *, const char *, const char *, INT);
1382         T ShellExecute;
1383         HMODULE shell32;
1384
1385         shell32 = LoadLibrary("shell32.dll");
1386         if (!shell32)
1387                 die("cannot load shell32.dll");
1388         ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
1389         if (!ShellExecute)
1390                 die("cannot run browser");
1391
1392         printf("Launching default browser to display HTML ...\n");
1393         ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1394
1395         FreeLibrary(shell32);
1396 }
1397
1398 int link(const char *oldpath, const char *newpath)
1399 {
1400         typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1401         static T create_hard_link = NULL;
1402         if (!create_hard_link) {
1403                 create_hard_link = (T) GetProcAddress(
1404                         GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1405                 if (!create_hard_link)
1406                         create_hard_link = (T)-1;
1407         }
1408         if (create_hard_link == (T)-1) {
1409                 errno = ENOSYS;
1410                 return -1;
1411         }
1412         if (!create_hard_link(newpath, oldpath, NULL)) {
1413                 errno = err_win_to_posix(GetLastError());
1414                 return -1;
1415         }
1416         return 0;
1417 }
1418
1419 char *getpass(const char *prompt)
1420 {
1421         struct strbuf buf = STRBUF_INIT;
1422
1423         fputs(prompt, stderr);
1424         for (;;) {
1425                 char c = _getch();
1426                 if (c == '\r' || c == '\n')
1427                         break;
1428                 strbuf_addch(&buf, c);
1429         }
1430         fputs("\n", stderr);
1431         return strbuf_detach(&buf, NULL);
1432 }
1433
1434 #ifndef NO_MINGW_REPLACE_READDIR
1435 /* MinGW readdir implementation to avoid extra lstats for Git */
1436 struct mingw_DIR
1437 {
1438         struct _finddata_t      dd_dta;         /* disk transfer area for this dir */
1439         struct mingw_dirent     dd_dir;         /* Our own implementation, including d_type */
1440         long                    dd_handle;      /* _findnext handle */
1441         int                     dd_stat;        /* 0 = next entry to read is first entry, -1 = off the end, positive = 0 based index of next entry */
1442         char                    dd_name[1];     /* given path for dir with search pattern (struct is extended) */
1443 };
1444
1445 struct dirent *mingw_readdir(DIR *dir)
1446 {
1447         WIN32_FIND_DATAA buf;
1448         HANDLE handle;
1449         struct mingw_DIR *mdir = (struct mingw_DIR*)dir;
1450
1451         if (!dir->dd_handle) {
1452                 errno = EBADF; /* No set_errno for mingw */
1453                 return NULL;
1454         }
1455
1456         if (dir->dd_handle == (long)INVALID_HANDLE_VALUE && dir->dd_stat == 0)
1457         {
1458                 DWORD lasterr;
1459                 handle = FindFirstFileA(dir->dd_name, &buf);
1460                 lasterr = GetLastError();
1461                 dir->dd_handle = (long)handle;
1462                 if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES)) {
1463                         errno = err_win_to_posix(lasterr);
1464                         return NULL;
1465                 }
1466         } else if (dir->dd_handle == (long)INVALID_HANDLE_VALUE) {
1467                 return NULL;
1468         } else if (!FindNextFileA((HANDLE)dir->dd_handle, &buf)) {
1469                 DWORD lasterr = GetLastError();
1470                 FindClose((HANDLE)dir->dd_handle);
1471                 dir->dd_handle = (long)INVALID_HANDLE_VALUE;
1472                 /* POSIX says you shouldn't set errno when readdir can't
1473                    find any more files; so, if another error we leave it set. */
1474                 if (lasterr != ERROR_NO_MORE_FILES)
1475                         errno = err_win_to_posix(lasterr);
1476                 return NULL;
1477         }
1478
1479         /* We get here if `buf' contains valid data.  */
1480         strcpy(dir->dd_dir.d_name, buf.cFileName);
1481         ++dir->dd_stat;
1482
1483         /* Set file type, based on WIN32_FIND_DATA */
1484         mdir->dd_dir.d_type = 0;
1485         if (buf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
1486                 mdir->dd_dir.d_type |= DT_DIR;
1487         else
1488                 mdir->dd_dir.d_type |= DT_REG;
1489
1490         return (struct dirent*)&dir->dd_dir;
1491 }
1492 #endif // !NO_MINGW_REPLACE_READDIR