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