compat/mingw.c

   1 #include "../git-compat-util.h"
   2 #include "win32.h"
   3 #include <conio.h>
   4 #include <winioctl.h>
   5 #include <shellapi.h>
   6 #include "../strbuf.h"
   7
   8 extern int hide_dotfiles;
   9 unsigned int _CRT_fmode = _O_BINARY;
  10
  11 static int err_win_to_posix(DWORD winerr)
  12 {
  13         int error = ENOSYS;
  14         switch(winerr) {
  15         case ERROR_ACCESS_DENIED: error = EACCES; break;
  16         case ERROR_ACCOUNT_DISABLED: error = EACCES; break;
  17         case ERROR_ACCOUNT_RESTRICTION: error = EACCES; break;
  18         case ERROR_ALREADY_ASSIGNED: error = EBUSY; break;
  19         case ERROR_ALREADY_EXISTS: error = EEXIST; break;
  20         case ERROR_ARITHMETIC_OVERFLOW: error = ERANGE; break;
  21         case ERROR_BAD_COMMAND: error = EIO; break;
  22         case ERROR_BAD_DEVICE: error = ENODEV; break;
  23         case ERROR_BAD_DRIVER_LEVEL: error = ENXIO; break;
  24         case ERROR_BAD_EXE_FORMAT: error = ENOEXEC; break;
  25         case ERROR_BAD_FORMAT: error = ENOEXEC; break;
  26         case ERROR_BAD_LENGTH: error = EINVAL; break;
  27         case ERROR_BAD_PATHNAME: error = ENOENT; break;
  28         case ERROR_BAD_PIPE: error = EPIPE; break;
  29         case ERROR_BAD_UNIT: error = ENODEV; break;
  30         case ERROR_BAD_USERNAME: error = EINVAL; break;
  31         case ERROR_BROKEN_PIPE: error = EPIPE; break;
  32         case ERROR_BUFFER_OVERFLOW: error = ENAMETOOLONG; break;
  33         case ERROR_BUSY: error = EBUSY; break;
  34         case ERROR_BUSY_DRIVE: error = EBUSY; break;
  35         case ERROR_CALL_NOT_IMPLEMENTED: error = ENOSYS; break;
  36         case ERROR_CANNOT_MAKE: error = EACCES; break;
  37         case ERROR_CANTOPEN: error = EIO; break;
  38         case ERROR_CANTREAD: error = EIO; break;
  39         case ERROR_CANTWRITE: error = EIO; break;
  40         case ERROR_CRC: error = EIO; break;
  41         case ERROR_CURRENT_DIRECTORY: error = EACCES; break;
  42         case ERROR_DEVICE_IN_USE: error = EBUSY; break;
  43         case ERROR_DEV_NOT_EXIST: error = ENODEV; break;
  44         case ERROR_DIRECTORY: error = EINVAL; break;
  45         case ERROR_DIR_NOT_EMPTY: error = ENOTEMPTY; break;
  46         case ERROR_DISK_CHANGE: error = EIO; break;
  47         case ERROR_DISK_FULL: error = ENOSPC; break;
  48         case ERROR_DRIVE_LOCKED: error = EBUSY; break;
  49         case ERROR_ENVVAR_NOT_FOUND: error = EINVAL; break;
  50         case ERROR_EXE_MARKED_INVALID: error = ENOEXEC; break;
  51         case ERROR_FILENAME_EXCED_RANGE: error = ENAMETOOLONG; break;
  52         case ERROR_FILE_EXISTS: error = EEXIST; break;
  53         case ERROR_FILE_INVALID: error = ENODEV; break;
  54         case ERROR_FILE_NOT_FOUND: error = ENOENT; break;
  55         case ERROR_GEN_FAILURE: error = EIO; break;
  56         case ERROR_HANDLE_DISK_FULL: error = ENOSPC; break;
  57         case ERROR_INSUFFICIENT_BUFFER: error = ENOMEM; break;
  58         case ERROR_INVALID_ACCESS: error = EACCES; break;
  59         case ERROR_INVALID_ADDRESS: error = EFAULT; break;
  60         case ERROR_INVALID_BLOCK: error = EFAULT; break;
  61         case ERROR_INVALID_DATA: error = EINVAL; break;
  62         case ERROR_INVALID_DRIVE: error = ENODEV; break;
  63         case ERROR_INVALID_EXE_SIGNATURE: error = ENOEXEC; break;
  64         case ERROR_INVALID_FLAGS: error = EINVAL; break;
  65         case ERROR_INVALID_FUNCTION: error = ENOSYS; break;
  66         case ERROR_INVALID_HANDLE: error = EBADF; break;
  67         case ERROR_INVALID_LOGON_HOURS: error = EACCES; break;
  68         case ERROR_INVALID_NAME: error = EINVAL; break;
  69         case ERROR_INVALID_OWNER: error = EINVAL; break;
  70         case ERROR_INVALID_PARAMETER: error = EINVAL; break;
  71         case ERROR_INVALID_PASSWORD: error = EPERM; break;
  72         case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
  73         case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
  74         case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
  75         case ERROR_INVALID_WORKSTATION: error = EACCES; break;
  76         case ERROR_IO_DEVICE: error = EIO; break;
  77         case ERROR_IO_INCOMPLETE: error = EINTR; break;
  78         case ERROR_LOCKED: error = EBUSY; break;
  79         case ERROR_LOCK_VIOLATION: error = EACCES; break;
  80         case ERROR_LOGON_FAILURE: error = EACCES; break;
  81         case ERROR_MAPPED_ALIGNMENT: error = EINVAL; break;
  82         case ERROR_META_EXPANSION_TOO_LONG: error = E2BIG; break;
  83         case ERROR_MORE_DATA: error = EPIPE; break;
  84         case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
  85         case ERROR_NOACCESS: error = EFAULT; break;
  86         case ERROR_NONE_MAPPED: error = EINVAL; break;
  87         case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
  88         case ERROR_NOT_READY: error = EAGAIN; break;
  89         case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
  90         case ERROR_NO_DATA: error = EPIPE; break;
  91         case ERROR_NO_MORE_SEARCH_HANDLES: error = EIO; break;
  92         case ERROR_NO_PROC_SLOTS: error = EAGAIN; break;
  93         case ERROR_NO_SUCH_PRIVILEGE: error = EACCES; break;
  94         case ERROR_OPEN_FAILED: error = EIO; break;
  95         case ERROR_OPEN_FILES: error = EBUSY; break;
  96         case ERROR_OPERATION_ABORTED: error = EINTR; break;
  97         case ERROR_OUTOFMEMORY: error = ENOMEM; break;
  98         case ERROR_PASSWORD_EXPIRED: error = EACCES; break;
  99         case ERROR_PATH_BUSY: error = EBUSY; break;
 100         case ERROR_PATH_NOT_FOUND: error = ENOENT; break;
 101         case ERROR_PIPE_BUSY: error = EBUSY; break;
 102         case ERROR_PIPE_CONNECTED: error = EPIPE; break;
 103         case ERROR_PIPE_LISTENING: error = EPIPE; break;
 104         case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 105         case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 106         case ERROR_READ_FAULT: error = EIO; break;
 107         case ERROR_SEEK: error = EIO; break;
 108         case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 109         case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;
 110         case ERROR_SHARING_VIOLATION: error = EACCES; break;
 111         case ERROR_STACK_OVERFLOW: error = ENOMEM; break;
 112         case ERROR_SWAPERROR: error = ENOENT; break;
 113         case ERROR_TOO_MANY_MODULES: error = EMFILE; break;
 114         case ERROR_TOO_MANY_OPEN_FILES: error = EMFILE; break;
 115         case ERROR_UNRECOGNIZED_MEDIA: error = ENXIO; break;
 116         case ERROR_UNRECOGNIZED_VOLUME: error = ENODEV; break;
 117         case ERROR_WAIT_NO_CHILDREN: error = ECHILD; break;
 118         case ERROR_WRITE_FAULT: error = EIO; break;
 119         case ERROR_WRITE_PROTECT: error = EROFS; break;
 120         }
 121         return error;
 122 }
 123
 124 static int make_hidden(const char *path)
 125 {
 126         DWORD attribs = GetFileAttributes(path);
 127         if (SetFileAttributes(path, FILE_ATTRIBUTE_HIDDEN | attribs))
 128                 return 0;
 129         errno = err_win_to_posix(GetLastError());
 130         return -1;
 131 }
 132
 133 #undef mkdir
 134 int mingw_mkdir(const char *path, int mode)
 135 {
 136         int ret = mkdir(path);
 137         if (!ret && hide_dotfiles) {
 138                 /*
 139                  * In Windows a file or dir starting with a dot is not
 140                  * automatically hidden. So lets mark it as hidden when
 141                  * such a directory is created.
 142                  */
 143                 const char *start = basename((char*)path);
 144                 if (*start == '.')
 145                         return make_hidden(path);
 146         }
 147         return ret;
 148 }
 149
 150 #undef open
 151 int mingw_open (const char *filename, int oflags, ...)
 152 {
 153         va_list args;
 154         unsigned mode;
 155         int fd;
 156
 157         va_start(args, oflags);
 158         mode = va_arg(args, int);
 159         va_end(args);
 160
 161         if (!strcmp(filename, "/dev/null"))
 162                 filename = "nul";
 163
 164         fd = open(filename, oflags, mode);
 165
 166         if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
 167                 DWORD attrs = GetFileAttributes(filename);
 168                 if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
 169                         errno = EISDIR;
 170         }
 171         if ((oflags & O_CREAT) && fd >= 0 && hide_dotfiles) {
 172                 /*
 173                  * In Windows a file or dir starting with a dot is not
 174                  * automatically hidden. So lets mark it as hidden when
 175                  * such a file is created.
 176                  */
 177                 const char *start = basename((char*)filename);
 178                 if (*start == '.' && make_hidden(filename))
 179                         warning("Could not mark '%s' as hidden.", filename);
 180         }
 181         return fd;
 182 }
 183
 184 static inline time_t filetime_to_time_t(const FILETIME *ft)
 185 {
 186         long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 187         winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
 188         winTime /= 10000000;             /* Nano to seconds resolution */
 189         return (time_t)winTime;
 190 }
 191
 192 /*
 193  * We keep the do_lstat code in a separate function to avoid recursion.
 194  * When a path ends with a slash, the stat will fail with ENOENT. In
 195  * this case, we strip the trailing slashes and stat again.
 196  */
 197 static int do_lstat(const char *file_name, struct stat *buf)
 198 {
 199         WIN32_FILE_ATTRIBUTE_DATA fdata;
 200
 201         if (!(errno = get_file_attr(file_name, &fdata))) {
 202                 buf->st_ino = 0;
 203                 buf->st_gid = 0;
 204                 buf->st_uid = 0;
 205                 buf->st_nlink = 1;
 206                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 207                 buf->st_size = fdata.nFileSizeLow |
 208                         (((off_t)fdata.nFileSizeHigh)<<32);
 209                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 210                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 211                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 212                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 213                 if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 214                         WIN32_FIND_DATAA findbuf;
 215                         HANDLE handle = FindFirstFileA(file_name, &findbuf);
 216                         if (handle != INVALID_HANDLE_VALUE) {
 217                                 if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
 218                                                 (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
 219                                         char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
 220                                         buf->st_mode = S_IREAD | S_IFLNK;
 221                                         if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 222                                                 buf->st_mode |= S_IWRITE;
 223                                         buf->st_size = readlink(file_name, buffer, MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
 224                                 }
 225                                 FindClose(handle);
 226                         }
 227                 }
 228                 return 0;
 229         }
 230         return -1;
 231 }
 232
 233 /*
 234  * We provide our own lstat/fstat functions, since the provided
 235  * lstat/fstat functions are so slow. These stat functions are
 236  * tailored for Git's usage (read: fast), and are not meant to be
 237  * complete. Note that Git stat()s are redirected to mingw_lstat()
 238  * too, since Windows doesn't really handle symlinks that well.
 239  */
 240 int mingw_lstat(const char *file_name, struct stat *buf)
 241 {
 242         int namelen;
 243         static char alt_name[PATH_MAX];
 244
 245         if (!do_lstat(file_name, buf))
 246                 return 0;
 247
 248         /*
 249          * if file_name ended in a '/', Windows returned ENOENT;
 250          * try again without trailing slashes
 251          */
 252         if (errno != ENOENT)
 253                 return -1;
 254
 255         namelen = strlen(file_name);
 256         if (namelen && file_name[namelen-1] != '/')
 257                 return -1;
 258         while (namelen && file_name[namelen-1] == '/')
 259                 --namelen;
 260         if (!namelen || namelen >= PATH_MAX)
 261                 return -1;
 262
 263         memcpy(alt_name, file_name, namelen);
 264         alt_name[namelen] = 0;
 265         return do_lstat(alt_name, buf);
 266 }
 267
 268 #undef fstat
 269 int mingw_fstat(int fd, struct stat *buf)
 270 {
 271         HANDLE fh = (HANDLE)_get_osfhandle(fd);
 272         BY_HANDLE_FILE_INFORMATION fdata;
 273
 274         if (fh == INVALID_HANDLE_VALUE) {
 275                 errno = EBADF;
 276                 return -1;
 277         }
 278         /* direct non-file handles to MS's fstat() */
 279         if (GetFileType(fh) != FILE_TYPE_DISK)
 280                 return _fstati64(fd, buf);
 281
 282         if (GetFileInformationByHandle(fh, &fdata)) {
 283                 buf->st_ino = 0;
 284                 buf->st_gid = 0;
 285                 buf->st_uid = 0;
 286                 buf->st_nlink = 1;
 287                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 288                 buf->st_size = fdata.nFileSizeLow |
 289                         (((off_t)fdata.nFileSizeHigh)<<32);
 290                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 291                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 292                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 293                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 294                 return 0;
 295         }
 296         errno = EBADF;
 297         return -1;
 298 }
 299
 300 static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 301 {
 302         long long winTime = t * 10000000LL + 116444736000000000LL;
 303         ft->dwLowDateTime = winTime;
 304         ft->dwHighDateTime = winTime >> 32;
 305 }
 306
 307 int mingw_utime (const char *file_name, const struct utimbuf *times)
 308 {
 309         FILETIME mft, aft;
 310         int fh, rc;
 311
 312         /* must have write permission */
 313         if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
 314                 return -1;
 315
 316         time_t_to_filetime(times->modtime, &mft);
 317         time_t_to_filetime(times->actime, &aft);
 318         if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 319                 errno = EINVAL;
 320                 rc = -1;
 321         } else
 322                 rc = 0;
 323         close(fh);
 324         return rc;
 325 }
 326
 327 unsigned int sleep (unsigned int seconds)
 328 {
 329         Sleep(seconds*1000);
 330         return 0;
 331 }
 332
 333 int mkstemp(char *template)
 334 {
 335         char *filename = mktemp(template);
 336         if (filename == NULL)
 337                 return -1;
 338         return open(filename, O_RDWR | O_CREAT, 0600);
 339 }
 340
 341 int gettimeofday(struct timeval *tv, void *tz)
 342 {
 343         SYSTEMTIME st;
 344         struct tm tm;
 345         GetSystemTime(&st);
 346         tm.tm_year = st.wYear-1900;
 347         tm.tm_mon = st.wMonth-1;
 348         tm.tm_mday = st.wDay;
 349         tm.tm_hour = st.wHour;
 350         tm.tm_min = st.wMinute;
 351         tm.tm_sec = st.wSecond;
 352         tv->tv_sec = tm_to_time_t(&tm);
 353         if (tv->tv_sec < 0)
 354                 return -1;
 355         tv->tv_usec = st.wMilliseconds*1000;
 356         return 0;
 357 }
 358
 359 int pipe(int filedes[2])
 360 {
 361         int fd;
 362         HANDLE h[2], parent;
 363
 364         if (_pipe(filedes, 8192, 0) < 0)
 365                 return -1;
 366
 367         parent = GetCurrentProcess();
 368
 369         if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[0]),
 370                         parent, &h[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 371                 close(filedes[0]);
 372                 close(filedes[1]);
 373                 return -1;
 374         }
 375         if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[1]),
 376                         parent, &h[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 377                 close(filedes[0]);
 378                 close(filedes[1]);
 379                 CloseHandle(h[0]);
 380                 return -1;
 381         }
 382         fd = _open_osfhandle((int)h[0], O_NOINHERIT);
 383         if (fd < 0) {
 384                 close(filedes[0]);
 385                 close(filedes[1]);
 386                 CloseHandle(h[0]);
 387                 CloseHandle(h[1]);
 388                 return -1;
 389         }
 390         close(filedes[0]);
 391         filedes[0] = fd;
 392         fd = _open_osfhandle((int)h[1], O_NOINHERIT);
 393         if (fd < 0) {
 394                 close(filedes[0]);
 395                 close(filedes[1]);
 396                 CloseHandle(h[1]);
 397                 return -1;
 398         }
 399         close(filedes[1]);
 400         filedes[1] = fd;
 401         return 0;
 402 }
 403
 404 int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 405 {
 406         int i, pending;
 407
 408         if (timeout >= 0) {
 409                 if (nfds == 0) {
 410                         Sleep(timeout);
 411                         return 0;
 412                 }
 413                 return errno = EINVAL, error("poll timeout not supported");
 414         }
 415
 416         /*
 417          * When there is only one fd to wait for, then we pretend that
 418          * input is available and let the actual wait happen when the
 419          * caller invokes read().
 420          */
 421         if (nfds == 1) {
 422                 if (!(ufds[0].events & POLLIN))
 423                         return errno = EINVAL, error("POLLIN not set");
 424                 ufds[0].revents = POLLIN;
 425                 return 0;
 426         }
 427
 428 repeat:
 429         pending = 0;
 430         for (i = 0; i < nfds; i++) {
 431                 DWORD avail = 0;
 432                 HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 433                 if (h == INVALID_HANDLE_VALUE)
 434                         return -1;      /* errno was set */
 435
 436                 if (!(ufds[i].events & POLLIN))
 437                         return errno = EINVAL, error("POLLIN not set");
 438
 439                 /* this emulation works only for pipes */
 440                 if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 441                         int err = GetLastError();
 442                         if (err == ERROR_BROKEN_PIPE) {
 443                                 ufds[i].revents = POLLHUP;
 444                                 pending++;
 445                         } else {
 446                                 errno = EINVAL;
 447                                 return error("PeekNamedPipe failed,"
 448                                         " GetLastError: %u", err);
 449                         }
 450                 } else if (avail) {
 451                         ufds[i].revents = POLLIN;
 452                         pending++;
 453                 } else
 454                         ufds[i].revents = 0;
 455         }
 456         if (!pending) {
 457                 /*
 458                  * The only times that we spin here is when the process
 459                  * that is connected through the pipes is waiting for
 460                  * its own input data to become available. But since
 461                  * the process (pack-objects) is itself CPU intensive,
 462                  * it will happily pick up the time slice that we are
 463                  * relinquishing here.
 464                  */
 465                 Sleep(0);
 466                 goto repeat;
 467         }
 468         return 0;
 469 }
 470
 471 struct tm *gmtime_r(const time_t *timep, struct tm *result)
 472 {
 473         /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 474         memcpy(result, gmtime(timep), sizeof(struct tm));
 475         return result;
 476 }
 477
 478 struct tm *localtime_r(const time_t *timep, struct tm *result)
 479 {
 480         /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 481         memcpy(result, localtime(timep), sizeof(struct tm));
 482         return result;
 483 }
 484
 485 #undef getcwd
 486 char *mingw_getcwd(char *pointer, int len)
 487 {
 488         int i;
 489         char *ret = getcwd(pointer, len);
 490         if (!ret)
 491                 return ret;
 492         for (i = 0; pointer[i]; i++)
 493                 if (pointer[i] == '\\')
 494                         pointer[i] = '/';
 495         return ret;
 496 }
 497
 498 #undef getenv
 499 char *mingw_getenv(const char *name)
 500 {
 501         char *result = getenv(name);
 502         if (!result && !strcmp(name, "TMPDIR")) {
 503                 /* on Windows it is TMP and TEMP */
 504                 result = getenv("TMP");
 505                 if (!result)
 506                         result = getenv("TEMP");
 507         }
 508         return result;
 509 }
 510
 511 /*
 512  * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 513  * (Parsing C++ Command-Line Arguments)
 514  */
 515 static const char *quote_arg(const char *arg)
 516 {
 517         /* count chars to quote */
 518         int len = 0, n = 0;
 519         int force_quotes = 0;
 520         char *q, *d;
 521         const char *p = arg;
 522         if (!*p) force_quotes = 1;
 523         while (*p) {
 524                 if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 525                         force_quotes = 1;
 526                 else if (*p == '"')
 527                         n++;
 528                 else if (*p == '\\') {
 529                         int count = 0;
 530                         while (*p == '\\') {
 531                                 count++;
 532                                 p++;
 533                                 len++;
 534                         }
 535                         if (*p == '"')
 536                                 n += count*2 + 1;
 537                         continue;
 538                 }
 539                 len++;
 540                 p++;
 541         }
 542         if (!force_quotes && n == 0)
 543                 return arg;
 544
 545         /* insert \ where necessary */
 546         d = q = xmalloc(len+n+3);
 547         *d++ = '"';
 548         while (*arg) {
 549                 if (*arg == '"')
 550                         *d++ = '\\';
 551                 else if (*arg == '\\') {
 552                         int count = 0;
 553                         while (*arg == '\\') {
 554                                 count++;
 555                                 *d++ = *arg++;
 556                         }
 557                         if (*arg == '"') {
 558                                 while (count-- > 0)
 559                                         *d++ = '\\';
 560                                 *d++ = '\\';
 561                         }
 562                 }
 563                 *d++ = *arg++;
 564         }
 565         *d++ = '"';
 566         *d++ = 0;
 567         return q;
 568 }
 569
 570 static const char *parse_interpreter(const char *cmd)
 571 {
 572         static char buf[100];
 573         char *p, *opt;
 574         int n, fd;
 575
 576         /* don't even try a .exe */
 577         n = strlen(cmd);
 578         if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 579                 return NULL;
 580
 581         fd = open(cmd, O_RDONLY);
 582         if (fd < 0)
 583                 return NULL;
 584         n = read(fd, buf, sizeof(buf)-1);
 585         close(fd);
 586         if (n < 4)      /* at least '#!/x' and not error */
 587                 return NULL;
 588
 589         if (buf[0] != '#' || buf[1] != '!')
 590                 return NULL;
 591         buf[n] = '\0';
 592         p = buf + strcspn(buf, "\r\n");
 593         if (!*p)
 594                 return NULL;
 595
 596         *p = '\0';
 597         if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 598                 return NULL;
 599         /* strip options */
 600         if ((opt = strchr(p+1, ' ')))
 601                 *opt = '\0';
 602         return p+1;
 603 }
 604
 605 /*
 606  * Splits the PATH into parts.
 607  */
 608 static char **get_path_split(void)
 609 {
 610         char *p, **path, *envpath = getenv("PATH");
 611         int i, n = 0;
 612
 613         if (!envpath || !*envpath)
 614                 return NULL;
 615
 616         envpath = xstrdup(envpath);
 617         p = envpath;
 618         while (p) {
 619                 char *dir = p;
 620                 p = strchr(p, ';');
 621                 if (p) *p++ = '\0';
 622                 if (*dir) {     /* not earlier, catches series of ; */
 623                         ++n;
 624                 }
 625         }
 626         if (!n)
 627                 return NULL;
 628
 629         path = xmalloc((n+1)*sizeof(char *));
 630         p = envpath;
 631         i = 0;
 632         do {
 633                 if (*p)
 634                         path[i++] = xstrdup(p);
 635                 p = p+strlen(p)+1;
 636         } while (i < n);
 637         path[i] = NULL;
 638
 639         free(envpath);
 640
 641         return path;
 642 }
 643
 644 static void free_path_split(char **path)
 645 {
 646         char **p = path;
 647
 648         if (!path)
 649                 return;
 650
 651         while (*p)
 652                 free(*p++);
 653         free(path);
 654 }
 655
 656 /*
 657  * exe_only means that we only want to detect .exe files, but not scripts
 658  * (which do not have an extension)
 659  */
 660 static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 661 {
 662         char path[MAX_PATH];
 663         snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 664
 665         if (!isexe && access(path, F_OK) == 0)
 666                 return xstrdup(path);
 667         path[strlen(path)-4] = '\0';
 668         if ((!exe_only || isexe) && access(path, F_OK) == 0)
 669                 if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 670                         return xstrdup(path);
 671         return NULL;
 672 }
 673
 674 /*
 675  * Determines the absolute path of cmd using the the split path in path.
 676  * If cmd contains a slash or backslash, no lookup is performed.
 677  */
 678 static char *path_lookup(const char *cmd, char **path, int exe_only)
 679 {
 680         char *prog = NULL;
 681         int len = strlen(cmd);
 682         int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 683
 684         if (strchr(cmd, '/') || strchr(cmd, '\\'))
 685                 prog = xstrdup(cmd);
 686
 687         while (!prog && *path)
 688                 prog = lookup_prog(*path++, cmd, isexe, exe_only);
 689
 690         return prog;
 691 }
 692
 693 static int env_compare(const void *a, const void *b)
 694 {
 695         char *const *ea = a;
 696         char *const *eb = b;
 697         return strcasecmp(*ea, *eb);
 698 }
 699
 700 static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 701                            int prepend_cmd)
 702 {
 703         STARTUPINFO si;
 704         PROCESS_INFORMATION pi;
 705         struct strbuf envblk, args;
 706         unsigned flags;
 707         BOOL ret;
 708
 709         /* Determine whether or not we are associated to a console */
 710         HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 711                         FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 712                         FILE_ATTRIBUTE_NORMAL, NULL);
 713         if (cons == INVALID_HANDLE_VALUE) {
 714                 /*
 715                  * There is no console associated with this process.
 716                  * Since the child is a console process, Windows
 717                  * would normally create a console window. But
 718                  * since we'll be redirecting std streams, we do
 719                  * not need the console.
 720                  * It is necessary to use DETACHED_PROCESS
 721                  * instead of CREATE_NO_WINDOW to make ssh
 722                  * recognize that it has no console.
 723                  */
 724                 flags = DETACHED_PROCESS;
 725         } else {
 726                 /*
 727                  * There is already a console. If we specified
 728                  * DETACHED_PROCESS here, too, Windows would
 729                  * disassociate the child from the console.
 730                  * The same is true for CREATE_NO_WINDOW.
 731                  * Go figure!
 732                  */
 733                 flags = 0;
 734                 CloseHandle(cons);
 735         }
 736         memset(&si, 0, sizeof(si));
 737         si.cb = sizeof(si);
 738         si.dwFlags = STARTF_USESTDHANDLES;
 739         si.hStdInput = (HANDLE) _get_osfhandle(0);
 740         si.hStdOutput = (HANDLE) _get_osfhandle(1);
 741         si.hStdError = (HANDLE) _get_osfhandle(2);
 742
 743         /* concatenate argv, quoting args as we go */
 744         strbuf_init(&args, 0);
 745         if (prepend_cmd) {
 746                 char *quoted = (char *)quote_arg(cmd);
 747                 strbuf_addstr(&args, quoted);
 748                 if (quoted != cmd)
 749                         free(quoted);
 750         }
 751         for (; *argv; argv++) {
 752                 char *quoted = (char *)quote_arg(*argv);
 753                 if (*args.buf)
 754                         strbuf_addch(&args, ' ');
 755                 strbuf_addstr(&args, quoted);
 756                 if (quoted != *argv)
 757                         free(quoted);
 758         }
 759
 760         if (env) {
 761                 int count = 0;
 762                 char **e, **sorted_env;
 763
 764                 for (e = env; *e; e++)
 765                         count++;
 766
 767                 /* environment must be sorted */
 768                 sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 769                 memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 770                 qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 771
 772                 strbuf_init(&envblk, 0);
 773                 for (e = sorted_env; *e; e++) {
 774                         strbuf_addstr(&envblk, *e);
 775                         strbuf_addch(&envblk, '\0');
 776                 }
 777                 free(sorted_env);
 778         }
 779
 780         memset(&pi, 0, sizeof(pi));
 781         ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 782                 env ? envblk.buf : NULL, NULL, &si, &pi);
 783
 784         if (env)
 785                 strbuf_release(&envblk);
 786         strbuf_release(&args);
 787
 788         if (!ret) {
 789                 errno = ENOENT;
 790                 return -1;
 791         }
 792         CloseHandle(pi.hThread);
 793         return (pid_t)pi.hProcess;
 794 }
 795
 796 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
 797 {
 798         pid_t pid;
 799         char **path = get_path_split();
 800         char *prog = path_lookup(cmd, path, 0);
 801
 802         if (!prog) {
 803                 errno = ENOENT;
 804                 pid = -1;
 805         }
 806         else {
 807                 const char *interpr = parse_interpreter(prog);
 808
 809                 if (interpr) {
 810                         const char *argv0 = argv[0];
 811                         char *iprog = path_lookup(interpr, path, 1);
 812                         argv[0] = prog;
 813                         if (!iprog) {
 814                                 errno = ENOENT;
 815                                 pid = -1;
 816                         }
 817                         else {
 818                                 pid = mingw_spawnve(iprog, argv, env, 1);
 819                                 free(iprog);
 820                         }
 821                         argv[0] = argv0;
 822                 }
 823                 else
 824                         pid = mingw_spawnve(prog, argv, env, 0);
 825                 free(prog);
 826         }
 827         free_path_split(path);
 828         return pid;
 829 }
 830
 831 static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 832 {
 833         const char *interpr = parse_interpreter(cmd);
 834         char **path;
 835         char *prog;
 836         int pid = 0;
 837
 838         if (!interpr)
 839                 return 0;
 840         path = get_path_split();
 841         prog = path_lookup(interpr, path, 1);
 842         if (prog) {
 843                 int argc = 0;
 844                 const char **argv2;
 845                 while (argv[argc]) argc++;
 846                 argv2 = xmalloc(sizeof(*argv) * (argc+1));
 847                 argv2[0] = (char *)cmd; /* full path to the script file */
 848                 memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 849                 pid = mingw_spawnve(prog, argv2, env, 1);
 850                 if (pid >= 0) {
 851                         int status;
 852                         if (waitpid(pid, &status, 0) < 0)
 853                                 status = 255;
 854                         exit(status);
 855                 }
 856                 pid = 1;        /* indicate that we tried but failed */
 857                 free(prog);
 858                 free(argv2);
 859         }
 860         free_path_split(path);
 861         return pid;
 862 }
 863
 864 static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 865 {
 866         /* check if git_command is a shell script */
 867         if (!try_shell_exec(cmd, argv, (char **)env)) {
 868                 int pid, status;
 869
 870                 pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 871                 if (pid < 0)
 872                         return;
 873                 if (waitpid(pid, &status, 0) < 0)
 874                         status = 255;
 875                 exit(status);
 876         }
 877 }
 878
 879 void mingw_execvp(const char *cmd, char *const *argv)
 880 {
 881         char **path = get_path_split();
 882         char *prog = path_lookup(cmd, path, 0);
 883
 884         if (prog) {
 885                 mingw_execve(prog, argv, environ);
 886                 free(prog);
 887         } else
 888                 errno = ENOENT;
 889
 890         free_path_split(path);
 891 }
 892
 893 static char **copy_environ(void)
 894 {
 895         char **env;
 896         int i = 0;
 897         while (environ[i])
 898                 i++;
 899         env = xmalloc((i+1)*sizeof(*env));
 900         for (i = 0; environ[i]; i++)
 901                 env[i] = xstrdup(environ[i]);
 902         env[i] = NULL;
 903         return env;
 904 }
 905
 906 void free_environ(char **env)
 907 {
 908         int i;
 909         for (i = 0; env[i]; i++)
 910                 free(env[i]);
 911         free(env);
 912 }
 913
 914 static int lookup_env(char **env, const char *name, size_t nmln)
 915 {
 916         int i;
 917
 918         for (i = 0; env[i]; i++) {
 919                 if (0 == strncmp(env[i], name, nmln)
 920                     && '=' == env[i][nmln])
 921                         /* matches */
 922                         return i;
 923         }
 924         return -1;
 925 }
 926
 927 /*
 928  * If name contains '=', then sets the variable, otherwise it unsets it
 929  */
 930 static char **env_setenv(char **env, const char *name)
 931 {
 932         char *eq = strchrnul(name, '=');
 933         int i = lookup_env(env, name, eq-name);
 934
 935         if (i < 0) {
 936                 if (*eq) {
 937                         for (i = 0; env[i]; i++)
 938                                 ;
 939                         env = xrealloc(env, (i+2)*sizeof(*env));
 940                         env[i] = xstrdup(name);
 941                         env[i+1] = NULL;
 942                 }
 943         }
 944         else {
 945                 free(env[i]);
 946                 if (*eq)
 947                         env[i] = xstrdup(name);
 948                 else
 949                         for (; env[i]; i++)
 950                                 env[i] = env[i+1];
 951         }
 952         return env;
 953 }
 954
 955 /*
 956  * Copies global environ and adjusts variables as specified by vars.
 957  */
 958 char **make_augmented_environ(const char *const *vars)
 959 {
 960         char **env = copy_environ();
 961
 962         while (*vars)
 963                 env = env_setenv(env, *vars++);
 964         return env;
 965 }
 966
 967 /* this is the first function to call into WS_32; initialize it */
 968 #undef gethostbyname
 969 struct hostent *mingw_gethostbyname(const char *host)
 970 {
 971         WSADATA wsa;
 972
 973         if (WSAStartup(MAKEWORD(2,2), &wsa))
 974                 die("unable to initialize winsock subsystem, error %d",
 975                         WSAGetLastError());
 976         atexit((void(*)(void)) WSACleanup);
 977         return gethostbyname(host);
 978 }
 979
 980 int mingw_socket(int domain, int type, int protocol)
 981 {
 982         int sockfd;
 983         SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
 984         if (s == INVALID_SOCKET) {
 985                 /*
 986                  * WSAGetLastError() values are regular BSD error codes
 987                  * biased by WSABASEERR.
 988                  * However, strerror() does not know about networking
 989                  * specific errors, which are values beginning at 38 or so.
 990                  * Therefore, we choose to leave the biased error code
 991                  * in errno so that _if_ someone looks up the code somewhere,
 992                  * then it is at least the number that are usually listed.
 993                  */
 994                 errno = WSAGetLastError();
 995                 return -1;
 996         }
 997         /* convert into a file descriptor */
 998         if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
 999                 closesocket(s);
1000                 return error("unable to make a socket file descriptor: %s",
1001                         strerror(errno));
1002         }
1003         return sockfd;
1004 }
1005
1006 #undef connect
1007 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1008 {
1009         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1010         return connect(s, sa, sz);
1011 }
1012
1013 #undef rename
1014 int mingw_rename(const char *pold, const char *pnew)
1015 {
1016         DWORD attrs, gle;
1017         int tries = 0;
1018         static const int delay[] = { 0, 1, 10, 20, 40 };
1019
1020         /*
1021          * Try native rename() first to get errno right.
1022          * It is based on MoveFile(), which cannot overwrite existing files.
1023          */
1024         if (!rename(pold, pnew))
1025                 return 0;
1026         if (errno != EEXIST)
1027                 return -1;
1028 repeat:
1029         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1030                 return 0;
1031         /* TODO: translate more errors */
1032         gle = GetLastError();
1033         if (gle == ERROR_ACCESS_DENIED &&
1034             (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1035                 if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1036                         errno = EISDIR;
1037                         return -1;
1038                 }
1039                 if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1040                     SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1041                         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1042                                 return 0;
1043                         gle = GetLastError();
1044                         /* revert file attributes on failure */
1045                         SetFileAttributes(pnew, attrs);
1046                 }
1047         }
1048         if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1049                 /*
1050                  * We assume that some other process had the source or
1051                  * destination file open at the wrong moment and retry.
1052                  * In order to give the other process a higher chance to
1053                  * complete its operation, we give up our time slice now.
1054                  * If we have to retry again, we do sleep a bit.
1055                  */
1056                 Sleep(delay[tries]);
1057                 tries++;
1058                 goto repeat;
1059         }
1060         errno = EACCES;
1061         return -1;
1062 }
1063
1064 struct passwd *getpwuid(int uid)
1065 {
1066         static char user_name[100];
1067         static struct passwd p;
1068
1069         DWORD len = sizeof(user_name);
1070         if (!GetUserName(user_name, &len))
1071                 return NULL;
1072         p.pw_name = user_name;
1073         p.pw_gecos = "unknown";
1074         p.pw_dir = NULL;
1075         return &p;
1076 }
1077
1078 static HANDLE timer_event;
1079 static HANDLE timer_thread;
1080 static int timer_interval;
1081 static int one_shot;
1082 static sig_handler_t timer_fn = SIG_DFL;
1083
1084 /*
1085  * The timer works like this:
1086  * The thread, ticktack(), is a trivial routine that most of the time
1087  * only waits to receive the signal to terminate. The main thread tells
1088  * the thread to terminate by setting the timer_event to the signalled
1089  * state.
1090  * But ticktack() interrupts the wait state after the timer's interval
1091  * length to call the signal handler.
1092  */
1093
1094 static unsigned __stdcall ticktack(void *dummy)
1095 {
1096         while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1097                 if (timer_fn == SIG_DFL)
1098                         die("Alarm");
1099                 if (timer_fn != SIG_IGN)
1100                         timer_fn(SIGALRM);
1101                 if (one_shot)
1102                         break;
1103         }
1104         return 0;
1105 }
1106
1107 static int start_timer_thread(void)
1108 {
1109         timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1110         if (timer_event) {
1111                 timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1112                 if (!timer_thread )
1113                         return errno = ENOMEM,
1114                                 error("cannot start timer thread");
1115         } else
1116                 return errno = ENOMEM,
1117                         error("cannot allocate resources for timer");
1118         return 0;
1119 }
1120
1121 static void stop_timer_thread(void)
1122 {
1123         if (timer_event)
1124                 SetEvent(timer_event);  /* tell thread to terminate */
1125         if (timer_thread) {
1126                 int rc = WaitForSingleObject(timer_thread, 1000);
1127                 if (rc == WAIT_TIMEOUT)
1128                         error("timer thread did not terminate timely");
1129                 else if (rc != WAIT_OBJECT_0)
1130                         error("waiting for timer thread failed: %lu",
1131                               GetLastError());
1132                 CloseHandle(timer_thread);
1133         }
1134         if (timer_event)
1135                 CloseHandle(timer_event);
1136         timer_event = NULL;
1137         timer_thread = NULL;
1138 }
1139
1140 static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1141 {
1142         return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1143 }
1144
1145 int setitimer(int type, struct itimerval *in, struct itimerval *out)
1146 {
1147         static const struct timeval zero;
1148         static int atexit_done;
1149
1150         if (out != NULL)
1151                 return errno = EINVAL,
1152                         error("setitimer param 3 != NULL not implemented");
1153         if (!is_timeval_eq(&in->it_interval, &zero) &&
1154             !is_timeval_eq(&in->it_interval, &in->it_value))
1155                 return errno = EINVAL,
1156                         error("setitimer: it_interval must be zero or eq it_value");
1157
1158         if (timer_thread)
1159                 stop_timer_thread();
1160
1161         if (is_timeval_eq(&in->it_value, &zero) &&
1162             is_timeval_eq(&in->it_interval, &zero))
1163                 return 0;
1164
1165         timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1166         one_shot = is_timeval_eq(&in->it_interval, &zero);
1167         if (!atexit_done) {
1168                 atexit(stop_timer_thread);
1169                 atexit_done = 1;
1170         }
1171         return start_timer_thread();
1172 }
1173
1174 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1175 {
1176         if (sig != SIGALRM)
1177                 return errno = EINVAL,
1178                         error("sigaction only implemented for SIGALRM");
1179         if (out != NULL)
1180                 return errno = EINVAL,
1181                         error("sigaction: param 3 != NULL not implemented");
1182
1183         timer_fn = in->sa_handler;
1184         return 0;
1185 }
1186
1187 #undef signal
1188 sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1189 {
1190         sig_handler_t old = timer_fn;
1191         if (sig != SIGALRM)
1192                 return signal(sig, handler);
1193         timer_fn = handler;
1194         return old;
1195 }
1196
1197 static const char *make_backslash_path(const char *path)
1198 {
1199         static char buf[PATH_MAX + 1];
1200         char *c;
1201
1202         if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1203                 die("Too long path: %.*s", 60, path);
1204
1205         for (c = buf; *c; c++) {
1206                 if (*c == '/')
1207                         *c = '\\';
1208         }
1209         return buf;
1210 }
1211
1212 void mingw_open_html(const char *unixpath)
1213 {
1214         const char *htmlpath = make_backslash_path(unixpath);
1215         printf("Launching default browser to display HTML ...\n");
1216         ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1217 }
1218
1219 int link(const char *oldpath, const char *newpath)
1220 {
1221         typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1222         static T create_hard_link = NULL;
1223         if (!create_hard_link) {
1224                 create_hard_link = (T) GetProcAddress(
1225                         GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1226                 if (!create_hard_link)
1227                         create_hard_link = (T)-1;
1228         }
1229         if (create_hard_link == (T)-1) {
1230                 errno = ENOSYS;
1231                 return -1;
1232         }
1233         if (!create_hard_link(newpath, oldpath, NULL)) {
1234                 errno = err_win_to_posix(GetLastError());
1235                 return -1;
1236         }
1237         return 0;
1238 }
1239
1240 int symlink(const char *oldpath, const char *newpath)
1241 {
1242         typedef BOOL WINAPI (*symlink_fn)(const char*, const char*, DWORD);
1243         static symlink_fn create_symbolic_link = NULL;
1244         if (!create_symbolic_link) {
1245                 create_symbolic_link = (symlink_fn) GetProcAddress(
1246                                 GetModuleHandle("kernel32.dll"), "CreateSymbolicLinkA");
1247                 if (!create_symbolic_link)
1248                         create_symbolic_link = (symlink_fn)-1;
1249         }
1250         if (create_symbolic_link == (symlink_fn)-1) {
1251                 errno = ENOSYS;
1252                 return -1;
1253         }
1254
1255         if (!create_symbolic_link(newpath, oldpath, 0)) {
1256                 errno = err_win_to_posix(GetLastError());
1257                 return -1;
1258         }
1259         return 0;
1260 }
1261
1262 int readlink(const char *path, char *buf, size_t bufsiz)
1263 {
1264         HANDLE handle = CreateFile(path, GENERIC_READ,
1265                         FILE_SHARE_READ|FILE_SHARE_WRITE|FILE_SHARE_DELETE,
1266                         NULL, OPEN_EXISTING,
1267                         FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OPEN_REPARSE_POINT,
1268                         NULL);
1269
1270         if (handle != INVALID_HANDLE_VALUE) {
1271                 unsigned char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
1272                 DWORD dummy = 0;
1273                 if (DeviceIoControl(handle, FSCTL_GET_REPARSE_POINT, NULL, 0, buffer,
1274                         MAXIMUM_REPARSE_DATA_BUFFER_SIZE, &dummy, NULL)) {
1275                         REPARSE_DATA_BUFFER *b = (REPARSE_DATA_BUFFER *) buffer;
1276                         if (b->ReparseTag == IO_REPARSE_TAG_SYMLINK) {
1277                                 int len = b->SymbolicLinkReparseBuffer.SubstituteNameLength / sizeof(wchar_t);
1278                                 int offset = b->SymbolicLinkReparseBuffer.SubstituteNameOffset / sizeof(wchar_t);
1279                                 snprintf(buf, bufsiz, "%*ls", len,  & b->SymbolicLinkReparseBuffer.PathBuffer[offset]);
1280                                 CloseHandle(handle);
1281                                 return len;
1282                         }
1283                 }
1284
1285                 CloseHandle(handle);
1286         }
1287
1288         errno = EINVAL;
1289         return -1;
1290 }
1291
1292 char *getpass(const char *prompt)
1293 {
1294         struct strbuf buf = STRBUF_INIT;
1295
1296         fputs(prompt, stderr);
1297         for (;;) {
1298                 char c = _getch();
1299                 if (c == '\r' || c == '\n')
1300                         break;
1301                 strbuf_addch(&buf, c);
1302         }
1303         fputs("\n", stderr);
1304         return strbuf_detach(&buf, NULL);
1305 }
1306
1307 #ifndef NO_MINGW_REPLACE_READDIR
1308 /* MinGW readdir implementation to avoid extra lstats for Git */
1309 struct mingw_DIR
1310 {
1311         struct _finddata_t      dd_dta;         /* disk transfer area for this dir */
1312         struct mingw_dirent     dd_dir;         /* Our own implementation, including d_type */
1313         long                    dd_handle;      /* _findnext handle */
1314         int                     dd_stat;        /* 0 = next entry to read is first entry, -1 = off the end, positive = 0 based index of next entry */
1315         char                    dd_name[1];     /* given path for dir with search pattern (struct is extended) */
1316 };
1317
1318 struct dirent *mingw_readdir(DIR *dir)
1319 {
1320         WIN32_FIND_DATAA buf;
1321         HANDLE handle;
1322         struct mingw_DIR *mdir = (struct mingw_DIR*)dir;
1323
1324         if (!dir->dd_handle) {
1325                 errno = EBADF; /* No set_errno for mingw */
1326                 return NULL;
1327         }
1328
1329         if (dir->dd_handle == (long)INVALID_HANDLE_VALUE && dir->dd_stat == 0)
1330         {
1331                 DWORD lasterr;
1332                 handle = FindFirstFileA(dir->dd_name, &buf);
1333                 lasterr = GetLastError();
1334                 dir->dd_handle = (long)handle;
1335                 if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES)) {
1336                         errno = err_win_to_posix(lasterr);
1337                         return NULL;
1338                 }
1339         } else if (dir->dd_handle == (long)INVALID_HANDLE_VALUE) {
1340                 return NULL;
1341         } else if (!FindNextFileA((HANDLE)dir->dd_handle, &buf)) {
1342                 DWORD lasterr = GetLastError();
1343                 FindClose((HANDLE)dir->dd_handle);
1344                 dir->dd_handle = (long)INVALID_HANDLE_VALUE;
1345                 /*
1346                  * POSIX says you shouldn't set errno when readdir can't
1347                  * find any more files; so, if another error we leave it set.
1348                  */
1349                 if (lasterr != ERROR_NO_MORE_FILES)
1350                         errno = err_win_to_posix(lasterr);
1351                 return NULL;
1352         }
1353
1354         /* We get here if `buf' contains valid data.  */
1355         strcpy(dir->dd_dir.d_name, buf.cFileName);
1356         ++dir->dd_stat;
1357
1358         /* Set file type, based on WIN32_FIND_DATA */
1359         mdir->dd_dir.d_type = 0;
1360         if ((buf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
1361                         (buf.dwReserved0 == IO_REPARSE_TAG_SYMLINK))
1362                 mdir->dd_dir.d_type |= DT_LNK;
1363         else if (buf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
1364                 mdir->dd_dir.d_type |= DT_DIR;
1365         else
1366                 mdir->dd_dir.d_type |= DT_REG;
1367
1368         return (struct dirent*)&dir->dd_dir;
1369 }
1370 #endif // !NO_MINGW_REPLACE_READDIR