compat/mingw.c

   1 #include "../git-compat-util.h"
   2 #include "win32.h"
   3 #include <conio.h>
   4 #include "../strbuf.h"
   5 #include "../cache.h"
   6
   7 unsigned int _CRT_fmode = _O_BINARY;
   8
   9 int err_win_to_posix(DWORD winerr)
  10 {
  11         int error = ENOSYS;
  12         switch(winerr) {
  13         case ERROR_ACCESS_DENIED: error = EACCES; break;
  14         case ERROR_ACCOUNT_DISABLED: error = EACCES; break;
  15         case ERROR_ACCOUNT_RESTRICTION: error = EACCES; break;
  16         case ERROR_ALREADY_ASSIGNED: error = EBUSY; break;
  17         case ERROR_ALREADY_EXISTS: error = EEXIST; break;
  18         case ERROR_ARITHMETIC_OVERFLOW: error = ERANGE; break;
  19         case ERROR_BAD_COMMAND: error = EIO; break;
  20         case ERROR_BAD_DEVICE: error = ENODEV; break;
  21         case ERROR_BAD_DRIVER_LEVEL: error = ENXIO; break;
  22         case ERROR_BAD_EXE_FORMAT: error = ENOEXEC; break;
  23         case ERROR_BAD_FORMAT: error = ENOEXEC; break;
  24         case ERROR_BAD_LENGTH: error = EINVAL; break;
  25         case ERROR_BAD_PATHNAME: error = ENOENT; break;
  26         case ERROR_BAD_PIPE: error = EPIPE; break;
  27         case ERROR_BAD_UNIT: error = ENODEV; break;
  28         case ERROR_BAD_USERNAME: error = EINVAL; break;
  29         case ERROR_BROKEN_PIPE: error = EPIPE; break;
  30         case ERROR_BUFFER_OVERFLOW: error = ENAMETOOLONG; break;
  31         case ERROR_BUSY: error = EBUSY; break;
  32         case ERROR_BUSY_DRIVE: error = EBUSY; break;
  33         case ERROR_CALL_NOT_IMPLEMENTED: error = ENOSYS; break;
  34         case ERROR_CANNOT_MAKE: error = EACCES; break;
  35         case ERROR_CANTOPEN: error = EIO; break;
  36         case ERROR_CANTREAD: error = EIO; break;
  37         case ERROR_CANTWRITE: error = EIO; break;
  38         case ERROR_CRC: error = EIO; break;
  39         case ERROR_CURRENT_DIRECTORY: error = EACCES; break;
  40         case ERROR_DEVICE_IN_USE: error = EBUSY; break;
  41         case ERROR_DEV_NOT_EXIST: error = ENODEV; break;
  42         case ERROR_DIRECTORY: error = EINVAL; break;
  43         case ERROR_DIR_NOT_EMPTY: error = ENOTEMPTY; break;
  44         case ERROR_DISK_CHANGE: error = EIO; break;
  45         case ERROR_DISK_FULL: error = ENOSPC; break;
  46         case ERROR_DRIVE_LOCKED: error = EBUSY; break;
  47         case ERROR_ENVVAR_NOT_FOUND: error = EINVAL; break;
  48         case ERROR_EXE_MARKED_INVALID: error = ENOEXEC; break;
  49         case ERROR_FILENAME_EXCED_RANGE: error = ENAMETOOLONG; break;
  50         case ERROR_FILE_EXISTS: error = EEXIST; break;
  51         case ERROR_FILE_INVALID: error = ENODEV; break;
  52         case ERROR_FILE_NOT_FOUND: error = ENOENT; break;
  53         case ERROR_GEN_FAILURE: error = EIO; break;
  54         case ERROR_HANDLE_DISK_FULL: error = ENOSPC; break;
  55         case ERROR_INSUFFICIENT_BUFFER: error = ENOMEM; break;
  56         case ERROR_INVALID_ACCESS: error = EACCES; break;
  57         case ERROR_INVALID_ADDRESS: error = EFAULT; break;
  58         case ERROR_INVALID_BLOCK: error = EFAULT; break;
  59         case ERROR_INVALID_DATA: error = EINVAL; break;
  60         case ERROR_INVALID_DRIVE: error = ENODEV; break;
  61         case ERROR_INVALID_EXE_SIGNATURE: error = ENOEXEC; break;
  62         case ERROR_INVALID_FLAGS: error = EINVAL; break;
  63         case ERROR_INVALID_FUNCTION: error = ENOSYS; break;
  64         case ERROR_INVALID_HANDLE: error = EBADF; break;
  65         case ERROR_INVALID_LOGON_HOURS: error = EACCES; break;
  66         case ERROR_INVALID_NAME: error = EINVAL; break;
  67         case ERROR_INVALID_OWNER: error = EINVAL; break;
  68         case ERROR_INVALID_PARAMETER: error = EINVAL; break;
  69         case ERROR_INVALID_PASSWORD: error = EPERM; break;
  70         case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
  71         case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
  72         case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
  73         case ERROR_INVALID_WORKSTATION: error = EACCES; break;
  74         case ERROR_IO_DEVICE: error = EIO; break;
  75         case ERROR_IO_INCOMPLETE: error = EINTR; break;
  76         case ERROR_LOCKED: error = EBUSY; break;
  77         case ERROR_LOCK_VIOLATION: error = EACCES; break;
  78         case ERROR_LOGON_FAILURE: error = EACCES; break;
  79         case ERROR_MAPPED_ALIGNMENT: error = EINVAL; break;
  80         case ERROR_META_EXPANSION_TOO_LONG: error = E2BIG; break;
  81         case ERROR_MORE_DATA: error = EPIPE; break;
  82         case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
  83         case ERROR_NOACCESS: error = EFAULT; break;
  84         case ERROR_NONE_MAPPED: error = EINVAL; break;
  85         case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
  86         case ERROR_NOT_READY: error = EAGAIN; break;
  87         case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
  88         case ERROR_NO_DATA: error = EPIPE; break;
  89         case ERROR_NO_MORE_SEARCH_HANDLES: error = EIO; break;
  90         case ERROR_NO_PROC_SLOTS: error = EAGAIN; break;
  91         case ERROR_NO_SUCH_PRIVILEGE: error = EACCES; break;
  92         case ERROR_OPEN_FAILED: error = EIO; break;
  93         case ERROR_OPEN_FILES: error = EBUSY; break;
  94         case ERROR_OPERATION_ABORTED: error = EINTR; break;
  95         case ERROR_OUTOFMEMORY: error = ENOMEM; break;
  96         case ERROR_PASSWORD_EXPIRED: error = EACCES; break;
  97         case ERROR_PATH_BUSY: error = EBUSY; break;
  98         case ERROR_PATH_NOT_FOUND: error = ENOENT; break;
  99         case ERROR_PIPE_BUSY: error = EBUSY; break;
 100         case ERROR_PIPE_CONNECTED: error = EPIPE; break;
 101         case ERROR_PIPE_LISTENING: error = EPIPE; break;
 102         case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 103         case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 104         case ERROR_READ_FAULT: error = EIO; break;
 105         case ERROR_SEEK: error = EIO; break;
 106         case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 107         case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;
 108         case ERROR_SHARING_VIOLATION: error = EACCES; break;
 109         case ERROR_STACK_OVERFLOW: error = ENOMEM; break;
 110         case ERROR_SWAPERROR: error = ENOENT; break;
 111         case ERROR_TOO_MANY_MODULES: error = EMFILE; break;
 112         case ERROR_TOO_MANY_OPEN_FILES: error = EMFILE; break;
 113         case ERROR_UNRECOGNIZED_MEDIA: error = ENXIO; break;
 114         case ERROR_UNRECOGNIZED_VOLUME: error = ENODEV; break;
 115         case ERROR_WAIT_NO_CHILDREN: error = ECHILD; break;
 116         case ERROR_WRITE_FAULT: error = EIO; break;
 117         case ERROR_WRITE_PROTECT: error = EROFS; break;
 118         }
 119         return error;
 120 }
 121
 122 static int make_hidden(const char *path)
 123 {
 124         DWORD attribs = GetFileAttributes(path);
 125         if (SetFileAttributes(path, FILE_ATTRIBUTE_HIDDEN | attribs))
 126                 return 0;
 127         errno = err_win_to_posix(GetLastError());
 128         return -1;
 129 }
 130
 131 void mingw_mark_as_git_dir(const char *dir)
 132 {
 133         if (hide_dotfiles != HIDE_DOTFILES_FALSE && make_hidden(dir))
 134                 warning("Failed to make '%s' hidden", dir);
 135         git_config_set("core.hideDotFiles",
 136                 hide_dotfiles == HIDE_DOTFILES_FALSE ? "false" :
 137                 (hide_dotfiles == HIDE_DOTFILES_DOTGITONLY ?
 138                  "dotGitOnly" : "true"));
 139 }
 140
 141 #undef mkdir
 142 int mingw_mkdir(const char *path, int mode)
 143 {
 144         int ret = mkdir(path);
 145         if (!ret && hide_dotfiles == HIDE_DOTFILES_TRUE) {
 146                 /*
 147                  * In Windows a file or dir starting with a dot is not
 148                  * automatically hidden. So lets mark it as hidden when
 149                  * such a directory is created.
 150                  */
 151                 const char *start = basename((char*)path);
 152                 if (*start == '.')
 153                         return make_hidden(path);
 154         }
 155         return ret;
 156 }
 157
 158 #undef open
 159 int mingw_open (const char *filename, int oflags, ...)
 160 {
 161         va_list args;
 162         unsigned mode;
 163         int fd;
 164
 165         va_start(args, oflags);
 166         mode = va_arg(args, int);
 167         va_end(args);
 168
 169         if (!strcmp(filename, "/dev/null"))
 170                 filename = "nul";
 171
 172         fd = open(filename, oflags, mode);
 173
 174         if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
 175                 DWORD attrs = GetFileAttributes(filename);
 176                 if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
 177                         errno = EISDIR;
 178         }
 179         if ((oflags & O_CREAT) && fd >= 0 &&
 180             hide_dotfiles == HIDE_DOTFILES_TRUE) {
 181                 /*
 182                  * In Windows a file or dir starting with a dot is not
 183                  * automatically hidden. So lets mark it as hidden when
 184                  * such a file is created.
 185                  */
 186                 const char *start = basename((char*)filename);
 187                 if (*start == '.' && make_hidden(filename))
 188                         warning("Could not mark '%s' as hidden.", filename);
 189         }
 190         return fd;
 191 }
 192
 193 #undef write
 194 ssize_t mingw_write(int fd, const void *buf, size_t count)
 195 {
 196         /*
 197          * While write() calls to a file on a local disk are translated
 198          * into WriteFile() calls with a maximum size of 64KB on Windows
 199          * XP and 256KB on Vista, no such cap is placed on writes to
 200          * files over the network on Windows XP.  Unfortunately, there
 201          * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86;
 202          * bigger writes fail on Windows XP.
 203          * So we cap to a nice 31MB here to avoid write failures over
 204          * the net without changing the number of WriteFile() calls in
 205          * the local case.
 206          */
 207         return write(fd, buf, min(count, 31 * 1024 * 1024));
 208 }
 209
 210 #undef fopen
 211 FILE *mingw_fopen (const char *filename, const char *otype)
 212 {
 213         int hide = 0;
 214         FILE *file;
 215         if (hide_dotfiles == HIDE_DOTFILES_TRUE &&
 216             basename((char*)filename)[0] == '.')
 217                 hide = access(filename, F_OK);
 218         if (!strcmp(filename, "/dev/null"))
 219                 filename = "nul";
 220         file = fopen(filename, otype);
 221         if (file && hide && make_hidden(filename))
 222                 warning("Could not mark '%s' as hidden.", filename);
 223         return file;
 224 }
 225
 226 #undef freopen
 227 FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 228 {
 229         int hide = 0;
 230         FILE *file;
 231         if (hide_dotfiles == HIDE_DOTFILES_TRUE &&
 232             basename((char*)filename)[0] == '.')
 233                 hide = access(filename, F_OK);
 234         if (filename && !strcmp(filename, "/dev/null"))
 235                 filename = "nul";
 236         file = freopen(filename, otype, stream);
 237         if (file && hide && make_hidden(filename))
 238                 warning("Could not mark '%s' as hidden.", filename);
 239         return file;
 240 }
 241
 242 /*
 243  * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
 244  * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
 245  */
 246 static inline long long filetime_to_hnsec(const FILETIME *ft)
 247 {
 248         long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 249         /* Windows to Unix Epoch conversion */
 250         return winTime - 116444736000000000LL;
 251 }
 252
 253 static inline time_t filetime_to_time_t(const FILETIME *ft)
 254 {
 255         return (time_t)(filetime_to_hnsec(ft) / 10000000);
 256 }
 257
 258 /* We keep the do_lstat code in a separate function to avoid recursion.
 259  * When a path ends with a slash, the stat will fail with ENOENT. In
 260  * this case, we strip the trailing slashes and stat again.
 261  */
 262 static int do_lstat(const char *file_name, struct stat *buf)
 263 {
 264         WIN32_FILE_ATTRIBUTE_DATA fdata;
 265
 266         if (!(errno = get_file_attr(file_name, &fdata))) {
 267                 buf->st_ino = 0;
 268                 buf->st_gid = 0;
 269                 buf->st_uid = 0;
 270                 buf->st_nlink = 1;
 271                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 272                 buf->st_size = fdata.nFileSizeLow |
 273                         (((off_t)fdata.nFileSizeHigh)<<32);
 274                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 275                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 276                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 277                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 278                 return 0;
 279         }
 280         return -1;
 281 }
 282
 283 /* We provide our own lstat/fstat functions, since the provided
 284  * lstat/fstat functions are so slow. These stat functions are
 285  * tailored for Git's usage (read: fast), and are not meant to be
 286  * complete. Note that Git stat()s are redirected to mingw_lstat()
 287  * too, since Windows doesn't really handle symlinks that well.
 288  */
 289 int mingw_lstat(const char *file_name, struct stat *buf)
 290 {
 291         int namelen;
 292         static char alt_name[PATH_MAX];
 293
 294         if (!do_lstat(file_name, buf))
 295                 return 0;
 296
 297         /* if file_name ended in a '/', Windows returned ENOENT;
 298          * try again without trailing slashes
 299          */
 300         if (errno != ENOENT)
 301                 return -1;
 302
 303         namelen = strlen(file_name);
 304         if (namelen && file_name[namelen-1] != '/')
 305                 return -1;
 306         while (namelen && file_name[namelen-1] == '/')
 307                 --namelen;
 308         if (!namelen || namelen >= PATH_MAX)
 309                 return -1;
 310
 311         memcpy(alt_name, file_name, namelen);
 312         alt_name[namelen] = 0;
 313         return do_lstat(alt_name, buf);
 314 }
 315
 316 #undef fstat
 317 int mingw_fstat(int fd, struct stat *buf)
 318 {
 319         HANDLE fh = (HANDLE)_get_osfhandle(fd);
 320         BY_HANDLE_FILE_INFORMATION fdata;
 321
 322         if (fh == INVALID_HANDLE_VALUE) {
 323                 errno = EBADF;
 324                 return -1;
 325         }
 326         /* direct non-file handles to MS's fstat() */
 327         if (GetFileType(fh) != FILE_TYPE_DISK)
 328                 return _fstati64(fd, buf);
 329
 330         if (GetFileInformationByHandle(fh, &fdata)) {
 331                 buf->st_ino = 0;
 332                 buf->st_gid = 0;
 333                 buf->st_uid = 0;
 334                 buf->st_nlink = 1;
 335                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 336                 buf->st_size = fdata.nFileSizeLow |
 337                         (((off_t)fdata.nFileSizeHigh)<<32);
 338                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 339                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 340                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 341                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 342                 return 0;
 343         }
 344         errno = EBADF;
 345         return -1;
 346 }
 347
 348 static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 349 {
 350         long long winTime = t * 10000000LL + 116444736000000000LL;
 351         ft->dwLowDateTime = winTime;
 352         ft->dwHighDateTime = winTime >> 32;
 353 }
 354
 355 int mingw_utime (const char *file_name, const struct utimbuf *times)
 356 {
 357         FILETIME mft, aft;
 358         int fh, rc;
 359
 360         /* must have write permission */
 361         DWORD attrs = GetFileAttributes(file_name);
 362         if (attrs != INVALID_FILE_ATTRIBUTES &&
 363             (attrs & FILE_ATTRIBUTE_READONLY)) {
 364                 /* ignore errors here; open() will report them */
 365                 SetFileAttributes(file_name, attrs & ~FILE_ATTRIBUTE_READONLY);
 366         }
 367
 368         if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0) {
 369                 rc = -1;
 370                 goto revert_attrs;
 371         }
 372
 373         time_t_to_filetime(times->modtime, &mft);
 374         time_t_to_filetime(times->actime, &aft);
 375         if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 376                 errno = EINVAL;
 377                 rc = -1;
 378         } else
 379                 rc = 0;
 380         close(fh);
 381
 382 revert_attrs:
 383         if (attrs != INVALID_FILE_ATTRIBUTES &&
 384             (attrs & FILE_ATTRIBUTE_READONLY)) {
 385                 /* ignore errors again */
 386                 SetFileAttributes(file_name, attrs);
 387         }
 388         return rc;
 389 }
 390
 391 unsigned int sleep (unsigned int seconds)
 392 {
 393         Sleep(seconds*1000);
 394         return 0;
 395 }
 396
 397 int mkstemp(char *template)
 398 {
 399         char *filename = mktemp(template);
 400         if (filename == NULL)
 401                 return -1;
 402         return open(filename, O_RDWR | O_CREAT, 0600);
 403 }
 404
 405 int gettimeofday(struct timeval *tv, void *tz)
 406 {
 407         FILETIME ft;
 408         long long hnsec;
 409
 410         GetSystemTimeAsFileTime(&ft);
 411         hnsec = filetime_to_hnsec(&ft);
 412         tv->tv_sec = hnsec / 10000000;
 413         tv->tv_usec = (hnsec % 10000000) / 10;
 414         return 0;
 415 }
 416
 417 int pipe(int filedes[2])
 418 {
 419         HANDLE h[2];
 420
 421         /* this creates non-inheritable handles */
 422         if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
 423                 errno = err_win_to_posix(GetLastError());
 424                 return -1;
 425         }
 426         filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
 427         if (filedes[0] < 0) {
 428                 CloseHandle(h[0]);
 429                 CloseHandle(h[1]);
 430                 return -1;
 431         }
 432         filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
 433         if (filedes[0] < 0) {
 434                 close(filedes[0]);
 435                 CloseHandle(h[1]);
 436                 return -1;
 437         }
 438         return 0;
 439 }
 440
 441 int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 442 {
 443         int i, pending;
 444
 445         if (timeout >= 0) {
 446                 if (nfds == 0) {
 447                         Sleep(timeout);
 448                         return 0;
 449                 }
 450                 return errno = EINVAL, error("poll timeout not supported");
 451         }
 452
 453         /* When there is only one fd to wait for, then we pretend that
 454          * input is available and let the actual wait happen when the
 455          * caller invokes read().
 456          */
 457         if (nfds == 1) {
 458                 if (!(ufds[0].events & POLLIN))
 459                         return errno = EINVAL, error("POLLIN not set");
 460                 ufds[0].revents = POLLIN;
 461                 return 0;
 462         }
 463
 464 repeat:
 465         pending = 0;
 466         for (i = 0; i < nfds; i++) {
 467                 DWORD avail = 0;
 468                 HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 469                 if (h == INVALID_HANDLE_VALUE)
 470                         return -1;      /* errno was set */
 471
 472                 if (!(ufds[i].events & POLLIN))
 473                         return errno = EINVAL, error("POLLIN not set");
 474
 475                 /* this emulation works only for pipes */
 476                 if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 477                         int err = GetLastError();
 478                         if (err == ERROR_BROKEN_PIPE) {
 479                                 ufds[i].revents = POLLHUP;
 480                                 pending++;
 481                         } else {
 482                                 errno = EINVAL;
 483                                 return error("PeekNamedPipe failed,"
 484                                         " GetLastError: %u", err);
 485                         }
 486                 } else if (avail) {
 487                         ufds[i].revents = POLLIN;
 488                         pending++;
 489                 } else
 490                         ufds[i].revents = 0;
 491         }
 492         if (!pending) {
 493                 /* The only times that we spin here is when the process
 494                  * that is connected through the pipes is waiting for
 495                  * its own input data to become available. But since
 496                  * the process (pack-objects) is itself CPU intensive,
 497                  * it will happily pick up the time slice that we are
 498                  * relinquishing here.
 499                  */
 500                 Sleep(0);
 501                 goto repeat;
 502         }
 503         return 0;
 504 }
 505
 506 struct tm *gmtime_r(const time_t *timep, struct tm *result)
 507 {
 508         /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 509         memcpy(result, gmtime(timep), sizeof(struct tm));
 510         return result;
 511 }
 512
 513 struct tm *localtime_r(const time_t *timep, struct tm *result)
 514 {
 515         /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 516         memcpy(result, localtime(timep), sizeof(struct tm));
 517         return result;
 518 }
 519
 520 #undef getcwd
 521 char *mingw_getcwd(char *pointer, int len)
 522 {
 523         int i;
 524         char *ret = getcwd(pointer, len);
 525         if (!ret)
 526                 return ret;
 527         for (i = 0; pointer[i]; i++)
 528                 if (pointer[i] == '\\')
 529                         pointer[i] = '/';
 530         return ret;
 531 }
 532
 533 #undef getenv
 534 char *mingw_getenv(const char *name)
 535 {
 536         char *result = getenv(name);
 537         if (!result && !strcmp(name, "TMPDIR")) {
 538                 /* on Windows it is TMP and TEMP */
 539                 result = getenv("TMP");
 540                 if (!result)
 541                         result = getenv("TEMP");
 542         }
 543         return result;
 544 }
 545
 546 /*
 547  * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 548  * (Parsing C++ Command-Line Arguments)
 549  */
 550 static const char *quote_arg(const char *arg)
 551 {
 552         /* count chars to quote */
 553         int len = 0, n = 0;
 554         int force_quotes = 0;
 555         char *q, *d;
 556         const char *p = arg;
 557         if (!*p) force_quotes = 1;
 558         while (*p) {
 559                 if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 560                         force_quotes = 1;
 561                 else if (*p == '"')
 562                         n++;
 563                 else if (*p == '\\') {
 564                         int count = 0;
 565                         while (*p == '\\') {
 566                                 count++;
 567                                 p++;
 568                                 len++;
 569                         }
 570                         if (*p == '"')
 571                                 n += count*2 + 1;
 572                         continue;
 573                 }
 574                 len++;
 575                 p++;
 576         }
 577         if (!force_quotes && n == 0)
 578                 return arg;
 579
 580         /* insert \ where necessary */
 581         d = q = xmalloc(len+n+3);
 582         *d++ = '"';
 583         while (*arg) {
 584                 if (*arg == '"')
 585                         *d++ = '\\';
 586                 else if (*arg == '\\') {
 587                         int count = 0;
 588                         while (*arg == '\\') {
 589                                 count++;
 590                                 *d++ = *arg++;
 591                         }
 592                         if (*arg == '"') {
 593                                 while (count-- > 0)
 594                                         *d++ = '\\';
 595                                 *d++ = '\\';
 596                         }
 597                 }
 598                 *d++ = *arg++;
 599         }
 600         *d++ = '"';
 601         *d++ = 0;
 602         return q;
 603 }
 604
 605 static const char *parse_interpreter(const char *cmd)
 606 {
 607         static char buf[100];
 608         char *p, *opt;
 609         int n, fd;
 610
 611         /* don't even try a .exe */
 612         n = strlen(cmd);
 613         if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 614                 return NULL;
 615
 616         fd = open(cmd, O_RDONLY);
 617         if (fd < 0)
 618                 return NULL;
 619         n = read(fd, buf, sizeof(buf)-1);
 620         close(fd);
 621         if (n < 4)      /* at least '#!/x' and not error */
 622                 return NULL;
 623
 624         if (buf[0] != '#' || buf[1] != '!')
 625                 return NULL;
 626         buf[n] = '\0';
 627         p = buf + strcspn(buf, "\r\n");
 628         if (!*p)
 629                 return NULL;
 630
 631         *p = '\0';
 632         if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 633                 return NULL;
 634         /* strip options */
 635         if ((opt = strchr(p+1, ' ')))
 636                 *opt = '\0';
 637         return p+1;
 638 }
 639
 640 /*
 641  * Splits the PATH into parts.
 642  */
 643 static char **get_path_split(void)
 644 {
 645         char *p, **path, *envpath = getenv("PATH");
 646         int i, n = 0;
 647
 648         if (!envpath || !*envpath)
 649                 return NULL;
 650
 651         envpath = xstrdup(envpath);
 652         p = envpath;
 653         while (p) {
 654                 char *dir = p;
 655                 p = strchr(p, ';');
 656                 if (p) *p++ = '\0';
 657                 if (*dir) {     /* not earlier, catches series of ; */
 658                         ++n;
 659                 }
 660         }
 661         if (!n)
 662                 return NULL;
 663
 664         path = xmalloc((n+1)*sizeof(char *));
 665         p = envpath;
 666         i = 0;
 667         do {
 668                 if (*p)
 669                         path[i++] = xstrdup(p);
 670                 p = p+strlen(p)+1;
 671         } while (i < n);
 672         path[i] = NULL;
 673
 674         free(envpath);
 675
 676         return path;
 677 }
 678
 679 static void free_path_split(char **path)
 680 {
 681         char **p = path;
 682
 683         if (!path)
 684                 return;
 685
 686         while (*p)
 687                 free(*p++);
 688         free(path);
 689 }
 690
 691 /*
 692  * exe_only means that we only want to detect .exe files, but not scripts
 693  * (which do not have an extension)
 694  */
 695 static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 696 {
 697         char path[MAX_PATH];
 698         snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 699
 700         if (!isexe && access(path, F_OK) == 0)
 701                 return xstrdup(path);
 702         path[strlen(path)-4] = '\0';
 703         if ((!exe_only || isexe) && access(path, F_OK) == 0)
 704                 if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 705                         return xstrdup(path);
 706         return NULL;
 707 }
 708
 709 /*
 710  * Determines the absolute path of cmd using the the split path in path.
 711  * If cmd contains a slash or backslash, no lookup is performed.
 712  */
 713 static char *path_lookup(const char *cmd, char **path, int exe_only)
 714 {
 715         char *prog = NULL;
 716         int len = strlen(cmd);
 717         int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 718
 719         if (strchr(cmd, '/') || strchr(cmd, '\\'))
 720                 prog = xstrdup(cmd);
 721
 722         while (!prog && *path)
 723                 prog = lookup_prog(*path++, cmd, isexe, exe_only);
 724
 725         return prog;
 726 }
 727
 728 static int env_compare(const void *a, const void *b)
 729 {
 730         char *const *ea = a;
 731         char *const *eb = b;
 732         return strcasecmp(*ea, *eb);
 733 }
 734
 735 static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
 736                               const char *dir,
 737                               int prepend_cmd, int fhin, int fhout, int fherr)
 738 {
 739         STARTUPINFO si;
 740         PROCESS_INFORMATION pi;
 741         struct strbuf envblk, args;
 742         unsigned flags;
 743         BOOL ret;
 744
 745         /* Determine whether or not we are associated to a console */
 746         HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 747                         FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 748                         FILE_ATTRIBUTE_NORMAL, NULL);
 749         if (cons == INVALID_HANDLE_VALUE) {
 750                 /* There is no console associated with this process.
 751                  * Since the child is a console process, Windows
 752                  * would normally create a console window. But
 753                  * since we'll be redirecting std streams, we do
 754                  * not need the console.
 755                  * It is necessary to use DETACHED_PROCESS
 756                  * instead of CREATE_NO_WINDOW to make ssh
 757                  * recognize that it has no console.
 758                  */
 759                 flags = DETACHED_PROCESS;
 760         } else {
 761                 /* There is already a console. If we specified
 762                  * DETACHED_PROCESS here, too, Windows would
 763                  * disassociate the child from the console.
 764                  * The same is true for CREATE_NO_WINDOW.
 765                  * Go figure!
 766                  */
 767                 flags = 0;
 768                 CloseHandle(cons);
 769         }
 770         memset(&si, 0, sizeof(si));
 771         si.cb = sizeof(si);
 772         si.dwFlags = STARTF_USESTDHANDLES;
 773         si.hStdInput = (HANDLE) _get_osfhandle(fhin);
 774         si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
 775         si.hStdError = (HANDLE) _get_osfhandle(fherr);
 776
 777         /* concatenate argv, quoting args as we go */
 778         strbuf_init(&args, 0);
 779         if (prepend_cmd) {
 780                 char *quoted = (char *)quote_arg(cmd);
 781                 strbuf_addstr(&args, quoted);
 782                 if (quoted != cmd)
 783                         free(quoted);
 784         }
 785         for (; *argv; argv++) {
 786                 char *quoted = (char *)quote_arg(*argv);
 787                 if (*args.buf)
 788                         strbuf_addch(&args, ' ');
 789                 strbuf_addstr(&args, quoted);
 790                 if (quoted != *argv)
 791                         free(quoted);
 792         }
 793
 794         if (env) {
 795                 int count = 0;
 796                 char **e, **sorted_env;
 797
 798                 for (e = env; *e; e++)
 799                         count++;
 800
 801                 /* environment must be sorted */
 802                 sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 803                 memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 804                 qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 805
 806                 strbuf_init(&envblk, 0);
 807                 for (e = sorted_env; *e; e++) {
 808                         strbuf_addstr(&envblk, *e);
 809                         strbuf_addch(&envblk, '\0');
 810                 }
 811                 free(sorted_env);
 812         }
 813
 814         memset(&pi, 0, sizeof(pi));
 815         ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 816                 env ? envblk.buf : NULL, dir, &si, &pi);
 817
 818         if (env)
 819                 strbuf_release(&envblk);
 820         strbuf_release(&args);
 821
 822         if (!ret) {
 823                 errno = ENOENT;
 824                 return -1;
 825         }
 826         CloseHandle(pi.hThread);
 827         return (pid_t)pi.hProcess;
 828 }
 829
 830 static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 831                            int prepend_cmd)
 832 {
 833         return mingw_spawnve_fd(cmd, argv, env, NULL, prepend_cmd, 0, 1, 2);
 834 }
 835
 836 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
 837                      const char *dir,
 838                      int fhin, int fhout, int fherr)
 839 {
 840         pid_t pid;
 841         char **path = get_path_split();
 842         char *prog = path_lookup(cmd, path, 0);
 843
 844         if (!prog) {
 845                 errno = ENOENT;
 846                 pid = -1;
 847         }
 848         else {
 849                 const char *interpr = parse_interpreter(prog);
 850
 851                 if (interpr) {
 852                         const char *argv0 = argv[0];
 853                         char *iprog = path_lookup(interpr, path, 1);
 854                         argv[0] = prog;
 855                         if (!iprog) {
 856                                 errno = ENOENT;
 857                                 pid = -1;
 858                         }
 859                         else {
 860                                 pid = mingw_spawnve_fd(iprog, argv, env, dir, 1,
 861                                                        fhin, fhout, fherr);
 862                                 free(iprog);
 863                         }
 864                         argv[0] = argv0;
 865                 }
 866                 else
 867                         pid = mingw_spawnve_fd(prog, argv, env, dir, 0,
 868                                                fhin, fhout, fherr);
 869                 free(prog);
 870         }
 871         free_path_split(path);
 872         return pid;
 873 }
 874
 875 static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 876 {
 877         const char *interpr = parse_interpreter(cmd);
 878         char **path;
 879         char *prog;
 880         int pid = 0;
 881
 882         if (!interpr)
 883                 return 0;
 884         path = get_path_split();
 885         prog = path_lookup(interpr, path, 1);
 886         if (prog) {
 887                 int argc = 0;
 888                 const char **argv2;
 889                 while (argv[argc]) argc++;
 890                 argv2 = xmalloc(sizeof(*argv) * (argc+1));
 891                 argv2[0] = (char *)cmd; /* full path to the script file */
 892                 memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 893                 pid = mingw_spawnve(prog, argv2, env, 1);
 894                 if (pid >= 0) {
 895                         int status;
 896                         if (waitpid(pid, &status, 0) < 0)
 897                                 status = 255;
 898                         exit(status);
 899                 }
 900                 pid = 1;        /* indicate that we tried but failed */
 901                 free(prog);
 902                 free(argv2);
 903         }
 904         free_path_split(path);
 905         return pid;
 906 }
 907
 908 static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 909 {
 910         /* check if git_command is a shell script */
 911         if (!try_shell_exec(cmd, argv, (char **)env)) {
 912                 int pid, status;
 913
 914                 pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 915                 if (pid < 0)
 916                         return;
 917                 if (waitpid(pid, &status, 0) < 0)
 918                         status = 255;
 919                 exit(status);
 920         }
 921 }
 922
 923 void mingw_execvp(const char *cmd, char *const *argv)
 924 {
 925         char **path = get_path_split();
 926         char *prog = path_lookup(cmd, path, 0);
 927
 928         if (prog) {
 929                 mingw_execve(prog, argv, environ);
 930                 free(prog);
 931         } else
 932                 errno = ENOENT;
 933
 934         free_path_split(path);
 935 }
 936
 937 static char **copy_environ(void)
 938 {
 939         char **env;
 940         int i = 0;
 941         while (environ[i])
 942                 i++;
 943         env = xmalloc((i+1)*sizeof(*env));
 944         for (i = 0; environ[i]; i++)
 945                 env[i] = xstrdup(environ[i]);
 946         env[i] = NULL;
 947         return env;
 948 }
 949
 950 void free_environ(char **env)
 951 {
 952         int i;
 953         for (i = 0; env[i]; i++)
 954                 free(env[i]);
 955         free(env);
 956 }
 957
 958 static int lookup_env(char **env, const char *name, size_t nmln)
 959 {
 960         int i;
 961
 962         for (i = 0; env[i]; i++) {
 963                 if (0 == strncmp(env[i], name, nmln)
 964                     && '=' == env[i][nmln])
 965                         /* matches */
 966                         return i;
 967         }
 968         return -1;
 969 }
 970
 971 /*
 972  * If name contains '=', then sets the variable, otherwise it unsets it
 973  */
 974 static char **env_setenv(char **env, const char *name)
 975 {
 976         char *eq = strchrnul(name, '=');
 977         int i = lookup_env(env, name, eq-name);
 978
 979         if (i < 0) {
 980                 if (*eq) {
 981                         for (i = 0; env[i]; i++)
 982                                 ;
 983                         env = xrealloc(env, (i+2)*sizeof(*env));
 984                         env[i] = xstrdup(name);
 985                         env[i+1] = NULL;
 986                 }
 987         }
 988         else {
 989                 free(env[i]);
 990                 if (*eq)
 991                         env[i] = xstrdup(name);
 992                 else
 993                         for (; env[i]; i++)
 994                                 env[i] = env[i+1];
 995         }
 996         return env;
 997 }
 998
 999 /*
1000  * Copies global environ and adjusts variables as specified by vars.
1001  */
1002 char **make_augmented_environ(const char *const *vars)
1003 {
1004         char **env = copy_environ();
1005
1006         while (*vars)
1007                 env = env_setenv(env, *vars++);
1008         return env;
1009 }
1010
1011 /*
1012  * Note, this isn't a complete replacement for getaddrinfo. It assumes
1013  * that service contains a numerical port, or that it it is null. It
1014  * does a simple search using gethostbyname, and returns one IPv4 host
1015  * if one was found.
1016  */
1017 static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
1018                                    const struct addrinfo *hints,
1019                                    struct addrinfo **res)
1020 {
1021         struct hostent *h = gethostbyname(node);
1022         struct addrinfo *ai;
1023         struct sockaddr_in *sin;
1024
1025         if (!h)
1026                 return WSAGetLastError();
1027
1028         ai = xmalloc(sizeof(struct addrinfo));
1029         *res = ai;
1030         ai->ai_flags = 0;
1031         ai->ai_family = AF_INET;
1032         ai->ai_socktype = hints->ai_socktype;
1033         switch (hints->ai_socktype) {
1034         case SOCK_STREAM:
1035                 ai->ai_protocol = IPPROTO_TCP;
1036                 break;
1037         case SOCK_DGRAM:
1038                 ai->ai_protocol = IPPROTO_UDP;
1039                 break;
1040         default:
1041                 ai->ai_protocol = 0;
1042                 break;
1043         }
1044         ai->ai_addrlen = sizeof(struct sockaddr_in);
1045         ai->ai_canonname = strdup(h->h_name);
1046
1047         sin = xmalloc(ai->ai_addrlen);
1048         memset(sin, 0, ai->ai_addrlen);
1049         sin->sin_family = AF_INET;
1050         if (service)
1051                 sin->sin_port = htons(atoi(service));
1052         sin->sin_addr = *(struct in_addr *)h->h_addr;
1053         ai->ai_addr = (struct sockaddr *)sin;
1054         ai->ai_next = 0;
1055         return 0;
1056 }
1057
1058 static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
1059 {
1060         free(res->ai_canonname);
1061         free(res->ai_addr);
1062         free(res);
1063 }
1064
1065 static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
1066                                    char *host, DWORD hostlen,
1067                                    char *serv, DWORD servlen, int flags)
1068 {
1069         const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
1070         if (sa->sa_family != AF_INET)
1071                 return EAI_FAMILY;
1072         if (!host && !serv)
1073                 return EAI_NONAME;
1074
1075         if (host && hostlen > 0) {
1076                 struct hostent *ent = NULL;
1077                 if (!(flags & NI_NUMERICHOST))
1078                         ent = gethostbyaddr((const char *)&sin->sin_addr,
1079                                             sizeof(sin->sin_addr), AF_INET);
1080
1081                 if (ent)
1082                         snprintf(host, hostlen, "%s", ent->h_name);
1083                 else if (flags & NI_NAMEREQD)
1084                         return EAI_NONAME;
1085                 else
1086                         snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
1087         }
1088
1089         if (serv && servlen > 0) {
1090                 struct servent *ent = NULL;
1091                 if (!(flags & NI_NUMERICSERV))
1092                         ent = getservbyport(sin->sin_port,
1093                                             flags & NI_DGRAM ? "udp" : "tcp");
1094
1095                 if (ent)
1096                         snprintf(serv, servlen, "%s", ent->s_name);
1097                 else
1098                         snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
1099         }
1100
1101         return 0;
1102 }
1103
1104 static HMODULE ipv6_dll = NULL;
1105 static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
1106 static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
1107                                       const struct addrinfo *hints,
1108                                       struct addrinfo **res);
1109 static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
1110                                       char *host, DWORD hostlen,
1111                                       char *serv, DWORD servlen, int flags);
1112 /*
1113  * gai_strerror is an inline function in the ws2tcpip.h header, so we
1114  * don't need to try to load that one dynamically.
1115  */
1116
1117 static void socket_cleanup(void)
1118 {
1119         WSACleanup();
1120         if (ipv6_dll)
1121                 FreeLibrary(ipv6_dll);
1122         ipv6_dll = NULL;
1123         ipv6_freeaddrinfo = freeaddrinfo_stub;
1124         ipv6_getaddrinfo = getaddrinfo_stub;
1125         ipv6_getnameinfo = getnameinfo_stub;
1126 }
1127
1128 static void ensure_socket_initialization(void)
1129 {
1130         WSADATA wsa;
1131         static int initialized = 0;
1132         const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
1133         const char **name;
1134
1135         if (initialized)
1136                 return;
1137
1138         if (WSAStartup(MAKEWORD(2,2), &wsa))
1139                 die("unable to initialize winsock subsystem, error %d",
1140                         WSAGetLastError());
1141
1142         for (name = libraries; *name; name++) {
1143                 ipv6_dll = LoadLibrary(*name);
1144                 if (!ipv6_dll)
1145                         continue;
1146
1147                 ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
1148                         GetProcAddress(ipv6_dll, "freeaddrinfo");
1149                 ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
1150                                                    const struct addrinfo *,
1151                                                    struct addrinfo **))
1152                         GetProcAddress(ipv6_dll, "getaddrinfo");
1153                 ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
1154                                                    socklen_t, char *, DWORD,
1155                                                    char *, DWORD, int))
1156                         GetProcAddress(ipv6_dll, "getnameinfo");
1157                 if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1158                         FreeLibrary(ipv6_dll);
1159                         ipv6_dll = NULL;
1160                 } else
1161                         break;
1162         }
1163         if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1164                 ipv6_freeaddrinfo = freeaddrinfo_stub;
1165                 ipv6_getaddrinfo = getaddrinfo_stub;
1166                 ipv6_getnameinfo = getnameinfo_stub;
1167         }
1168
1169         atexit(socket_cleanup);
1170         initialized = 1;
1171 }
1172
1173 #undef gethostbyname
1174 struct hostent *mingw_gethostbyname(const char *host)
1175 {
1176         ensure_socket_initialization();
1177         return gethostbyname(host);
1178 }
1179
1180 void mingw_freeaddrinfo(struct addrinfo *res)
1181 {
1182         ipv6_freeaddrinfo(res);
1183 }
1184
1185 int mingw_getaddrinfo(const char *node, const char *service,
1186                       const struct addrinfo *hints, struct addrinfo **res)
1187 {
1188         ensure_socket_initialization();
1189         return ipv6_getaddrinfo(node, service, hints, res);
1190 }
1191
1192 int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
1193                       char *host, DWORD hostlen, char *serv, DWORD servlen,
1194                       int flags)
1195 {
1196         ensure_socket_initialization();
1197         return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
1198 }
1199
1200 int mingw_socket(int domain, int type, int protocol)
1201 {
1202         int sockfd;
1203         SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
1204         if (s == INVALID_SOCKET) {
1205                 /*
1206                  * WSAGetLastError() values are regular BSD error codes
1207                  * biased by WSABASEERR.
1208                  * However, strerror() does not know about networking
1209                  * specific errors, which are values beginning at 38 or so.
1210                  * Therefore, we choose to leave the biased error code
1211                  * in errno so that _if_ someone looks up the code somewhere,
1212                  * then it is at least the number that are usually listed.
1213                  */
1214                 errno = WSAGetLastError();
1215                 return -1;
1216         }
1217         /* convert into a file descriptor */
1218         if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
1219                 closesocket(s);
1220                 return error("unable to make a socket file descriptor: %s",
1221                         strerror(errno));
1222         }
1223         return sockfd;
1224 }
1225
1226 #undef connect
1227 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1228 {
1229         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1230         return connect(s, sa, sz);
1231 }
1232
1233 #undef rename
1234 int mingw_rename(const char *pold, const char *pnew)
1235 {
1236         DWORD attrs, gle;
1237         int tries = 0;
1238         static const int delay[] = { 0, 1, 10, 20, 40 };
1239
1240         /*
1241          * Try native rename() first to get errno right.
1242          * It is based on MoveFile(), which cannot overwrite existing files.
1243          */
1244         if (!rename(pold, pnew))
1245                 return 0;
1246         if (errno != EEXIST)
1247                 return -1;
1248 repeat:
1249         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1250                 return 0;
1251         /* TODO: translate more errors */
1252         gle = GetLastError();
1253         if (gle == ERROR_ACCESS_DENIED &&
1254             (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1255                 if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1256                         errno = EISDIR;
1257                         return -1;
1258                 }
1259                 if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1260                     SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1261                         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1262                                 return 0;
1263                         gle = GetLastError();
1264                         /* revert file attributes on failure */
1265                         SetFileAttributes(pnew, attrs);
1266                 }
1267         }
1268         if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1269                 /*
1270                  * We assume that some other process had the source or
1271                  * destination file open at the wrong moment and retry.
1272                  * In order to give the other process a higher chance to
1273                  * complete its operation, we give up our time slice now.
1274                  * If we have to retry again, we do sleep a bit.
1275                  */
1276                 Sleep(delay[tries]);
1277                 tries++;
1278                 goto repeat;
1279         }
1280         errno = EACCES;
1281         return -1;
1282 }
1283
1284 /*
1285  * Note that this doesn't return the actual pagesize, but
1286  * the allocation granularity. If future Windows specific git code
1287  * needs the real getpagesize function, we need to find another solution.
1288  */
1289 int mingw_getpagesize(void)
1290 {
1291         SYSTEM_INFO si;
1292         GetSystemInfo(&si);
1293         return si.dwAllocationGranularity;
1294 }
1295
1296 struct passwd *getpwuid(int uid)
1297 {
1298         static char user_name[100];
1299         static struct passwd p;
1300
1301         DWORD len = sizeof(user_name);
1302         if (!GetUserName(user_name, &len))
1303                 return NULL;
1304         p.pw_name = user_name;
1305         p.pw_gecos = "unknown";
1306         p.pw_dir = NULL;
1307         return &p;
1308 }
1309
1310 static HANDLE timer_event;
1311 static HANDLE timer_thread;
1312 static int timer_interval;
1313 static int one_shot;
1314 static sig_handler_t timer_fn = SIG_DFL;
1315
1316 /* The timer works like this:
1317  * The thread, ticktack(), is a trivial routine that most of the time
1318  * only waits to receive the signal to terminate. The main thread tells
1319  * the thread to terminate by setting the timer_event to the signalled
1320  * state.
1321  * But ticktack() interrupts the wait state after the timer's interval
1322  * length to call the signal handler.
1323  */
1324
1325 static unsigned __stdcall ticktack(void *dummy)
1326 {
1327         while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1328                 if (timer_fn == SIG_DFL)
1329                         die("Alarm");
1330                 if (timer_fn != SIG_IGN)
1331                         timer_fn(SIGALRM);
1332                 if (one_shot)
1333                         break;
1334         }
1335         return 0;
1336 }
1337
1338 static int start_timer_thread(void)
1339 {
1340         timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1341         if (timer_event) {
1342                 timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1343                 if (!timer_thread )
1344                         return errno = ENOMEM,
1345                                 error("cannot start timer thread");
1346         } else
1347                 return errno = ENOMEM,
1348                         error("cannot allocate resources for timer");
1349         return 0;
1350 }
1351
1352 static void stop_timer_thread(void)
1353 {
1354         if (timer_event)
1355                 SetEvent(timer_event);  /* tell thread to terminate */
1356         if (timer_thread) {
1357                 int rc = WaitForSingleObject(timer_thread, 1000);
1358                 if (rc == WAIT_TIMEOUT)
1359                         error("timer thread did not terminate timely");
1360                 else if (rc != WAIT_OBJECT_0)
1361                         error("waiting for timer thread failed: %lu",
1362                               GetLastError());
1363                 CloseHandle(timer_thread);
1364         }
1365         if (timer_event)
1366                 CloseHandle(timer_event);
1367         timer_event = NULL;
1368         timer_thread = NULL;
1369 }
1370
1371 static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1372 {
1373         return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1374 }
1375
1376 int setitimer(int type, struct itimerval *in, struct itimerval *out)
1377 {
1378         static const struct timeval zero;
1379         static int atexit_done;
1380
1381         if (out != NULL)
1382                 return errno = EINVAL,
1383                         error("setitimer param 3 != NULL not implemented");
1384         if (!is_timeval_eq(&in->it_interval, &zero) &&
1385             !is_timeval_eq(&in->it_interval, &in->it_value))
1386                 return errno = EINVAL,
1387                         error("setitimer: it_interval must be zero or eq it_value");
1388
1389         if (timer_thread)
1390                 stop_timer_thread();
1391
1392         if (is_timeval_eq(&in->it_value, &zero) &&
1393             is_timeval_eq(&in->it_interval, &zero))
1394                 return 0;
1395
1396         timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1397         one_shot = is_timeval_eq(&in->it_interval, &zero);
1398         if (!atexit_done) {
1399                 atexit(stop_timer_thread);
1400                 atexit_done = 1;
1401         }
1402         return start_timer_thread();
1403 }
1404
1405 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1406 {
1407         if (sig != SIGALRM)
1408                 return errno = EINVAL,
1409                         error("sigaction only implemented for SIGALRM");
1410         if (out != NULL)
1411                 return errno = EINVAL,
1412                         error("sigaction: param 3 != NULL not implemented");
1413
1414         timer_fn = in->sa_handler;
1415         return 0;
1416 }
1417
1418 #undef signal
1419 sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1420 {
1421         sig_handler_t old = timer_fn;
1422         if (sig != SIGALRM)
1423                 return signal(sig, handler);
1424         timer_fn = handler;
1425         return old;
1426 }
1427
1428 static const char *make_backslash_path(const char *path)
1429 {
1430         static char buf[PATH_MAX + 1];
1431         char *c;
1432
1433         if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1434                 die("Too long path: %.*s", 60, path);
1435
1436         for (c = buf; *c; c++) {
1437                 if (*c == '/')
1438                         *c = '\\';
1439         }
1440         return buf;
1441 }
1442
1443 void mingw_open_html(const char *unixpath)
1444 {
1445         const char *htmlpath = make_backslash_path(unixpath);
1446         typedef HINSTANCE (WINAPI *T)(HWND, const char *,
1447                         const char *, const char *, const char *, INT);
1448         T ShellExecute;
1449         HMODULE shell32;
1450
1451         shell32 = LoadLibrary("shell32.dll");
1452         if (!shell32)
1453                 die("cannot load shell32.dll");
1454         ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
1455         if (!ShellExecute)
1456                 die("cannot run browser");
1457
1458         printf("Launching default browser to display HTML ...\n");
1459         ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1460
1461         FreeLibrary(shell32);
1462 }
1463
1464 int link(const char *oldpath, const char *newpath)
1465 {
1466         typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1467         static T create_hard_link = NULL;
1468         if (!create_hard_link) {
1469                 create_hard_link = (T) GetProcAddress(
1470                         GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1471                 if (!create_hard_link)
1472                         create_hard_link = (T)-1;
1473         }
1474         if (create_hard_link == (T)-1) {
1475                 errno = ENOSYS;
1476                 return -1;
1477         }
1478         if (!create_hard_link(newpath, oldpath, NULL)) {
1479                 errno = err_win_to_posix(GetLastError());
1480                 return -1;
1481         }
1482         return 0;
1483 }
1484
1485 char *getpass(const char *prompt)
1486 {
1487         struct strbuf buf = STRBUF_INIT;
1488
1489         fputs(prompt, stderr);
1490         for (;;) {
1491                 char c = _getch();
1492                 if (c == '\r' || c == '\n')
1493                         break;
1494                 strbuf_addch(&buf, c);
1495         }
1496         fputs("\n", stderr);
1497         return strbuf_detach(&buf, NULL);
1498 }
1499
1500 #ifndef NO_MINGW_REPLACE_READDIR
1501 /* MinGW readdir implementation to avoid extra lstats for Git */
1502 struct mingw_DIR
1503 {
1504         struct _finddata_t      dd_dta;         /* disk transfer area for this dir */
1505         struct mingw_dirent     dd_dir;         /* Our own implementation, including d_type */
1506         long                    dd_handle;      /* _findnext handle */
1507         int                     dd_stat;        /* 0 = next entry to read is first entry, -1 = off the end, positive = 0 based index of next entry */
1508         char                    dd_name[1];     /* given path for dir with search pattern (struct is extended) */
1509 };
1510
1511 struct dirent *mingw_readdir(DIR *dir)
1512 {
1513         WIN32_FIND_DATAA buf;
1514         HANDLE handle;
1515         struct mingw_DIR *mdir = (struct mingw_DIR*)dir;
1516
1517         if (!dir->dd_handle) {
1518                 errno = EBADF; /* No set_errno for mingw */
1519                 return NULL;
1520         }
1521
1522         if (dir->dd_handle == (long)INVALID_HANDLE_VALUE && dir->dd_stat == 0)
1523         {
1524                 DWORD lasterr;
1525                 handle = FindFirstFileA(dir->dd_name, &buf);
1526                 lasterr = GetLastError();
1527                 dir->dd_handle = (long)handle;
1528                 if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES)) {
1529                         errno = err_win_to_posix(lasterr);
1530                         return NULL;
1531                 }
1532         } else if (dir->dd_handle == (long)INVALID_HANDLE_VALUE) {
1533                 return NULL;
1534         } else if (!FindNextFileA((HANDLE)dir->dd_handle, &buf)) {
1535                 DWORD lasterr = GetLastError();
1536                 FindClose((HANDLE)dir->dd_handle);
1537                 dir->dd_handle = (long)INVALID_HANDLE_VALUE;
1538                 /* POSIX says you shouldn't set errno when readdir can't
1539                    find any more files; so, if another error we leave it set. */
1540                 if (lasterr != ERROR_NO_MORE_FILES)
1541                         errno = err_win_to_posix(lasterr);
1542                 return NULL;
1543         }
1544
1545         /* We get here if `buf' contains valid data.  */
1546         strcpy(dir->dd_dir.d_name, buf.cFileName);
1547         ++dir->dd_stat;
1548
1549         /* Set file type, based on WIN32_FIND_DATA */
1550         mdir->dd_dir.d_type = 0;
1551         if (buf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
1552                 mdir->dd_dir.d_type |= DT_DIR;
1553         else
1554                 mdir->dd_dir.d_type |= DT_REG;
1555
1556         return (struct dirent*)&dir->dd_dir;
1557 }
1558 #endif // !NO_MINGW_REPLACE_READDIR