compat/mingw.c

   1 #include "../git-compat-util.h"
   2 #include "win32.h"
   3 #include <conio.h>
   4 #include "../strbuf.h"
   5
   6 int err_win_to_posix(DWORD winerr)
   7 {
   8         int error = ENOSYS;
   9         switch(winerr) {
  10         case ERROR_ACCESS_DENIED: error = EACCES; break;
  11         case ERROR_ACCOUNT_DISABLED: error = EACCES; break;
  12         case ERROR_ACCOUNT_RESTRICTION: error = EACCES; break;
  13         case ERROR_ALREADY_ASSIGNED: error = EBUSY; break;
  14         case ERROR_ALREADY_EXISTS: error = EEXIST; break;
  15         case ERROR_ARITHMETIC_OVERFLOW: error = ERANGE; break;
  16         case ERROR_BAD_COMMAND: error = EIO; break;
  17         case ERROR_BAD_DEVICE: error = ENODEV; break;
  18         case ERROR_BAD_DRIVER_LEVEL: error = ENXIO; break;
  19         case ERROR_BAD_EXE_FORMAT: error = ENOEXEC; break;
  20         case ERROR_BAD_FORMAT: error = ENOEXEC; break;
  21         case ERROR_BAD_LENGTH: error = EINVAL; break;
  22         case ERROR_BAD_PATHNAME: error = ENOENT; break;
  23         case ERROR_BAD_PIPE: error = EPIPE; break;
  24         case ERROR_BAD_UNIT: error = ENODEV; break;
  25         case ERROR_BAD_USERNAME: error = EINVAL; break;
  26         case ERROR_BROKEN_PIPE: error = EPIPE; break;
  27         case ERROR_BUFFER_OVERFLOW: error = ENAMETOOLONG; break;
  28         case ERROR_BUSY: error = EBUSY; break;
  29         case ERROR_BUSY_DRIVE: error = EBUSY; break;
  30         case ERROR_CALL_NOT_IMPLEMENTED: error = ENOSYS; break;
  31         case ERROR_CANNOT_MAKE: error = EACCES; break;
  32         case ERROR_CANTOPEN: error = EIO; break;
  33         case ERROR_CANTREAD: error = EIO; break;
  34         case ERROR_CANTWRITE: error = EIO; break;
  35         case ERROR_CRC: error = EIO; break;
  36         case ERROR_CURRENT_DIRECTORY: error = EACCES; break;
  37         case ERROR_DEVICE_IN_USE: error = EBUSY; break;
  38         case ERROR_DEV_NOT_EXIST: error = ENODEV; break;
  39         case ERROR_DIRECTORY: error = EINVAL; break;
  40         case ERROR_DIR_NOT_EMPTY: error = ENOTEMPTY; break;
  41         case ERROR_DISK_CHANGE: error = EIO; break;
  42         case ERROR_DISK_FULL: error = ENOSPC; break;
  43         case ERROR_DRIVE_LOCKED: error = EBUSY; break;
  44         case ERROR_ENVVAR_NOT_FOUND: error = EINVAL; break;
  45         case ERROR_EXE_MARKED_INVALID: error = ENOEXEC; break;
  46         case ERROR_FILENAME_EXCED_RANGE: error = ENAMETOOLONG; break;
  47         case ERROR_FILE_EXISTS: error = EEXIST; break;
  48         case ERROR_FILE_INVALID: error = ENODEV; break;
  49         case ERROR_FILE_NOT_FOUND: error = ENOENT; break;
  50         case ERROR_GEN_FAILURE: error = EIO; break;
  51         case ERROR_HANDLE_DISK_FULL: error = ENOSPC; break;
  52         case ERROR_INSUFFICIENT_BUFFER: error = ENOMEM; break;
  53         case ERROR_INVALID_ACCESS: error = EACCES; break;
  54         case ERROR_INVALID_ADDRESS: error = EFAULT; break;
  55         case ERROR_INVALID_BLOCK: error = EFAULT; break;
  56         case ERROR_INVALID_DATA: error = EINVAL; break;
  57         case ERROR_INVALID_DRIVE: error = ENODEV; break;
  58         case ERROR_INVALID_EXE_SIGNATURE: error = ENOEXEC; break;
  59         case ERROR_INVALID_FLAGS: error = EINVAL; break;
  60         case ERROR_INVALID_FUNCTION: error = ENOSYS; break;
  61         case ERROR_INVALID_HANDLE: error = EBADF; break;
  62         case ERROR_INVALID_LOGON_HOURS: error = EACCES; break;
  63         case ERROR_INVALID_NAME: error = EINVAL; break;
  64         case ERROR_INVALID_OWNER: error = EINVAL; break;
  65         case ERROR_INVALID_PARAMETER: error = EINVAL; break;
  66         case ERROR_INVALID_PASSWORD: error = EPERM; break;
  67         case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
  68         case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
  69         case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
  70         case ERROR_INVALID_WORKSTATION: error = EACCES; break;
  71         case ERROR_IO_DEVICE: error = EIO; break;
  72         case ERROR_IO_INCOMPLETE: error = EINTR; break;
  73         case ERROR_LOCKED: error = EBUSY; break;
  74         case ERROR_LOCK_VIOLATION: error = EACCES; break;
  75         case ERROR_LOGON_FAILURE: error = EACCES; break;
  76         case ERROR_MAPPED_ALIGNMENT: error = EINVAL; break;
  77         case ERROR_META_EXPANSION_TOO_LONG: error = E2BIG; break;
  78         case ERROR_MORE_DATA: error = EPIPE; break;
  79         case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
  80         case ERROR_NOACCESS: error = EFAULT; break;
  81         case ERROR_NONE_MAPPED: error = EINVAL; break;
  82         case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
  83         case ERROR_NOT_READY: error = EAGAIN; break;
  84         case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
  85         case ERROR_NO_DATA: error = EPIPE; break;
  86         case ERROR_NO_MORE_SEARCH_HANDLES: error = EIO; break;
  87         case ERROR_NO_PROC_SLOTS: error = EAGAIN; break;
  88         case ERROR_NO_SUCH_PRIVILEGE: error = EACCES; break;
  89         case ERROR_OPEN_FAILED: error = EIO; break;
  90         case ERROR_OPEN_FILES: error = EBUSY; break;
  91         case ERROR_OPERATION_ABORTED: error = EINTR; break;
  92         case ERROR_OUTOFMEMORY: error = ENOMEM; break;
  93         case ERROR_PASSWORD_EXPIRED: error = EACCES; break;
  94         case ERROR_PATH_BUSY: error = EBUSY; break;
  95         case ERROR_PATH_NOT_FOUND: error = ENOENT; break;
  96         case ERROR_PIPE_BUSY: error = EBUSY; break;
  97         case ERROR_PIPE_CONNECTED: error = EPIPE; break;
  98         case ERROR_PIPE_LISTENING: error = EPIPE; break;
  99         case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 100         case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 101         case ERROR_READ_FAULT: error = EIO; break;
 102         case ERROR_SEEK: error = EIO; break;
 103         case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 104         case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;
 105         case ERROR_SHARING_VIOLATION: error = EACCES; break;
 106         case ERROR_STACK_OVERFLOW: error = ENOMEM; break;
 107         case ERROR_SWAPERROR: error = ENOENT; break;
 108         case ERROR_TOO_MANY_MODULES: error = EMFILE; break;
 109         case ERROR_TOO_MANY_OPEN_FILES: error = EMFILE; break;
 110         case ERROR_UNRECOGNIZED_MEDIA: error = ENXIO; break;
 111         case ERROR_UNRECOGNIZED_VOLUME: error = ENODEV; break;
 112         case ERROR_WAIT_NO_CHILDREN: error = ECHILD; break;
 113         case ERROR_WRITE_FAULT: error = EIO; break;
 114         case ERROR_WRITE_PROTECT: error = EROFS; break;
 115         }
 116         return error;
 117 }
 118
 119 #undef open
 120 int mingw_open (const char *filename, int oflags, ...)
 121 {
 122         va_list args;
 123         unsigned mode;
 124         int fd;
 125
 126         va_start(args, oflags);
 127         mode = va_arg(args, int);
 128         va_end(args);
 129
 130         if (filename && !strcmp(filename, "/dev/null"))
 131                 filename = "nul";
 132
 133         fd = open(filename, oflags, mode);
 134
 135         if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
 136                 DWORD attrs = GetFileAttributes(filename);
 137                 if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
 138                         errno = EISDIR;
 139         }
 140         return fd;
 141 }
 142
 143 #undef write
 144 ssize_t mingw_write(int fd, const void *buf, size_t count)
 145 {
 146         /*
 147          * While write() calls to a file on a local disk are translated
 148          * into WriteFile() calls with a maximum size of 64KB on Windows
 149          * XP and 256KB on Vista, no such cap is placed on writes to
 150          * files over the network on Windows XP.  Unfortunately, there
 151          * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86;
 152          * bigger writes fail on Windows XP.
 153          * So we cap to a nice 31MB here to avoid write failures over
 154          * the net without changing the number of WriteFile() calls in
 155          * the local case.
 156          */
 157         return write(fd, buf, min(count, 31 * 1024 * 1024));
 158 }
 159
 160 #undef fopen
 161 FILE *mingw_fopen (const char *filename, const char *otype)
 162 {
 163         if (filename && !strcmp(filename, "/dev/null"))
 164                 filename = "nul";
 165         return fopen(filename, otype);
 166 }
 167
 168 #undef freopen
 169 FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 170 {
 171         if (filename && !strcmp(filename, "/dev/null"))
 172                 filename = "nul";
 173         return freopen(filename, otype, stream);
 174 }
 175
 176 /*
 177  * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
 178  * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
 179  */
 180 static inline long long filetime_to_hnsec(const FILETIME *ft)
 181 {
 182         long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 183         /* Windows to Unix Epoch conversion */
 184         return winTime - 116444736000000000LL;
 185 }
 186
 187 static inline time_t filetime_to_time_t(const FILETIME *ft)
 188 {
 189         return (time_t)(filetime_to_hnsec(ft) / 10000000);
 190 }
 191
 192 /* We keep the do_lstat code in a separate function to avoid recursion.
 193  * When a path ends with a slash, the stat will fail with ENOENT. In
 194  * this case, we strip the trailing slashes and stat again.
 195  *
 196  * If follow is true then act like stat() and report on the link
 197  * target. Otherwise report on the link itself.
 198  */
 199 static int do_lstat(int follow, const char *file_name, struct stat *buf)
 200 {
 201         WIN32_FILE_ATTRIBUTE_DATA fdata;
 202
 203         if (!(errno = get_file_attr(file_name, &fdata))) {
 204                 buf->st_ino = 0;
 205                 buf->st_gid = 0;
 206                 buf->st_uid = 0;
 207                 buf->st_nlink = 1;
 208                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 209                 buf->st_size = fdata.nFileSizeLow |
 210                         (((off_t)fdata.nFileSizeHigh)<<32);
 211                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 212                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 213                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 214                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 215                 if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 216                         WIN32_FIND_DATAA findbuf;
 217                         HANDLE handle = FindFirstFileA(file_name, &findbuf);
 218                         if (handle != INVALID_HANDLE_VALUE) {
 219                                 if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
 220                                                 (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
 221                                         if (follow) {
 222                                                 char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
 223                                                 buf->st_size = readlink(file_name, buffer, MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
 224                                         } else {
 225                                                 buf->st_mode = S_IFLNK;
 226                                         }
 227                                         buf->st_mode |= S_IREAD;
 228                                         if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 229                                                 buf->st_mode |= S_IWRITE;
 230                                 }
 231                                 FindClose(handle);
 232                         }
 233                 }
 234                 return 0;
 235         }
 236         return -1;
 237 }
 238
 239 /* We provide our own lstat/fstat functions, since the provided
 240  * lstat/fstat functions are so slow. These stat functions are
 241  * tailored for Git's usage (read: fast), and are not meant to be
 242  * complete. Note that Git stat()s are redirected to mingw_lstat()
 243  * too, since Windows doesn't really handle symlinks that well.
 244  */
 245 static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 246 {
 247         int namelen;
 248         static char alt_name[PATH_MAX];
 249
 250         if (!do_lstat(follow, file_name, buf))
 251                 return 0;
 252
 253         /* if file_name ended in a '/', Windows returned ENOENT;
 254          * try again without trailing slashes
 255          */
 256         if (errno != ENOENT)
 257                 return -1;
 258
 259         namelen = strlen(file_name);
 260         if (namelen && file_name[namelen-1] != '/')
 261                 return -1;
 262         while (namelen && file_name[namelen-1] == '/')
 263                 --namelen;
 264         if (!namelen || namelen >= PATH_MAX)
 265                 return -1;
 266
 267         memcpy(alt_name, file_name, namelen);
 268         alt_name[namelen] = 0;
 269         return do_lstat(follow, alt_name, buf);
 270 }
 271
 272 int mingw_lstat(const char *file_name, struct stat *buf)
 273 {
 274         return do_stat_internal(0, file_name, buf);
 275 }
 276 int mingw_stat(const char *file_name, struct stat *buf)
 277 {
 278         return do_stat_internal(1, file_name, buf);
 279 }
 280
 281 #undef fstat
 282 int mingw_fstat(int fd, struct stat *buf)
 283 {
 284         HANDLE fh = (HANDLE)_get_osfhandle(fd);
 285         BY_HANDLE_FILE_INFORMATION fdata;
 286
 287         if (fh == INVALID_HANDLE_VALUE) {
 288                 errno = EBADF;
 289                 return -1;
 290         }
 291         /* direct non-file handles to MS's fstat() */
 292         if (GetFileType(fh) != FILE_TYPE_DISK)
 293                 return _fstati64(fd, buf);
 294
 295         if (GetFileInformationByHandle(fh, &fdata)) {
 296                 buf->st_ino = 0;
 297                 buf->st_gid = 0;
 298                 buf->st_uid = 0;
 299                 buf->st_nlink = 1;
 300                 buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 301                 buf->st_size = fdata.nFileSizeLow |
 302                         (((off_t)fdata.nFileSizeHigh)<<32);
 303                 buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 304                 buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 305                 buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 306                 buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 307                 return 0;
 308         }
 309         errno = EBADF;
 310         return -1;
 311 }
 312
 313 static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 314 {
 315         long long winTime = t * 10000000LL + 116444736000000000LL;
 316         ft->dwLowDateTime = winTime;
 317         ft->dwHighDateTime = winTime >> 32;
 318 }
 319
 320 int mingw_utime (const char *file_name, const struct utimbuf *times)
 321 {
 322         FILETIME mft, aft;
 323         int fh, rc;
 324
 325         /* must have write permission */
 326         DWORD attrs = GetFileAttributes(file_name);
 327         if (attrs != INVALID_FILE_ATTRIBUTES &&
 328             (attrs & FILE_ATTRIBUTE_READONLY)) {
 329                 /* ignore errors here; open() will report them */
 330                 SetFileAttributes(file_name, attrs & ~FILE_ATTRIBUTE_READONLY);
 331         }
 332
 333         if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0) {
 334                 rc = -1;
 335                 goto revert_attrs;
 336         }
 337
 338         if (times) {
 339                 time_t_to_filetime(times->modtime, &mft);
 340                 time_t_to_filetime(times->actime, &aft);
 341         } else {
 342                 GetSystemTimeAsFileTime(&mft);
 343                 aft = mft;
 344         }
 345         if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 346                 errno = EINVAL;
 347                 rc = -1;
 348         } else
 349                 rc = 0;
 350         close(fh);
 351
 352 revert_attrs:
 353         if (attrs != INVALID_FILE_ATTRIBUTES &&
 354             (attrs & FILE_ATTRIBUTE_READONLY)) {
 355                 /* ignore errors again */
 356                 SetFileAttributes(file_name, attrs);
 357         }
 358         return rc;
 359 }
 360
 361 unsigned int sleep (unsigned int seconds)
 362 {
 363         Sleep(seconds*1000);
 364         return 0;
 365 }
 366
 367 int mkstemp(char *template)
 368 {
 369         char *filename = mktemp(template);
 370         if (filename == NULL)
 371                 return -1;
 372         return open(filename, O_RDWR | O_CREAT, 0600);
 373 }
 374
 375 int gettimeofday(struct timeval *tv, void *tz)
 376 {
 377         FILETIME ft;
 378         long long hnsec;
 379
 380         GetSystemTimeAsFileTime(&ft);
 381         hnsec = filetime_to_hnsec(&ft);
 382         tv->tv_sec = hnsec / 10000000;
 383         tv->tv_usec = (hnsec % 10000000) / 10;
 384         return 0;
 385 }
 386
 387 int pipe(int filedes[2])
 388 {
 389         HANDLE h[2];
 390
 391         /* this creates non-inheritable handles */
 392         if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
 393                 errno = err_win_to_posix(GetLastError());
 394                 return -1;
 395         }
 396         filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
 397         if (filedes[0] < 0) {
 398                 CloseHandle(h[0]);
 399                 CloseHandle(h[1]);
 400                 return -1;
 401         }
 402         filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
 403         if (filedes[0] < 0) {
 404                 close(filedes[0]);
 405                 CloseHandle(h[1]);
 406                 return -1;
 407         }
 408         return 0;
 409 }
 410
 411 struct tm *gmtime_r(const time_t *timep, struct tm *result)
 412 {
 413         /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 414         memcpy(result, gmtime(timep), sizeof(struct tm));
 415         return result;
 416 }
 417
 418 struct tm *localtime_r(const time_t *timep, struct tm *result)
 419 {
 420         /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 421         memcpy(result, localtime(timep), sizeof(struct tm));
 422         return result;
 423 }
 424
 425 #undef getcwd
 426 char *mingw_getcwd(char *pointer, int len)
 427 {
 428         int i;
 429         char *ret = getcwd(pointer, len);
 430         if (!ret)
 431                 return ret;
 432         for (i = 0; pointer[i]; i++)
 433                 if (pointer[i] == '\\')
 434                         pointer[i] = '/';
 435         return ret;
 436 }
 437
 438 #undef getenv
 439 char *mingw_getenv(const char *name)
 440 {
 441         char *result = getenv(name);
 442         if (!result && !strcmp(name, "TMPDIR")) {
 443                 /* on Windows it is TMP and TEMP */
 444                 result = getenv("TMP");
 445                 if (!result)
 446                         result = getenv("TEMP");
 447         }
 448         return result;
 449 }
 450
 451 /*
 452  * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 453  * (Parsing C++ Command-Line Arguments)
 454  */
 455 static const char *quote_arg(const char *arg)
 456 {
 457         /* count chars to quote */
 458         int len = 0, n = 0;
 459         int force_quotes = 0;
 460         char *q, *d;
 461         const char *p = arg;
 462         if (!*p) force_quotes = 1;
 463         while (*p) {
 464                 if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 465                         force_quotes = 1;
 466                 else if (*p == '"')
 467                         n++;
 468                 else if (*p == '\\') {
 469                         int count = 0;
 470                         while (*p == '\\') {
 471                                 count++;
 472                                 p++;
 473                                 len++;
 474                         }
 475                         if (*p == '"')
 476                                 n += count*2 + 1;
 477                         continue;
 478                 }
 479                 len++;
 480                 p++;
 481         }
 482         if (!force_quotes && n == 0)
 483                 return arg;
 484
 485         /* insert \ where necessary */
 486         d = q = xmalloc(len+n+3);
 487         *d++ = '"';
 488         while (*arg) {
 489                 if (*arg == '"')
 490                         *d++ = '\\';
 491                 else if (*arg == '\\') {
 492                         int count = 0;
 493                         while (*arg == '\\') {
 494                                 count++;
 495                                 *d++ = *arg++;
 496                         }
 497                         if (*arg == '"') {
 498                                 while (count-- > 0)
 499                                         *d++ = '\\';
 500                                 *d++ = '\\';
 501                         }
 502                 }
 503                 *d++ = *arg++;
 504         }
 505         *d++ = '"';
 506         *d++ = 0;
 507         return q;
 508 }
 509
 510 static const char *parse_interpreter(const char *cmd)
 511 {
 512         static char buf[100];
 513         char *p, *opt;
 514         int n, fd;
 515
 516         /* don't even try a .exe */
 517         n = strlen(cmd);
 518         if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 519                 return NULL;
 520
 521         fd = open(cmd, O_RDONLY);
 522         if (fd < 0)
 523                 return NULL;
 524         n = read(fd, buf, sizeof(buf)-1);
 525         close(fd);
 526         if (n < 4)      /* at least '#!/x' and not error */
 527                 return NULL;
 528
 529         if (buf[0] != '#' || buf[1] != '!')
 530                 return NULL;
 531         buf[n] = '\0';
 532         p = buf + strcspn(buf, "\r\n");
 533         if (!*p)
 534                 return NULL;
 535
 536         *p = '\0';
 537         if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 538                 return NULL;
 539         /* strip options */
 540         if ((opt = strchr(p+1, ' ')))
 541                 *opt = '\0';
 542         return p+1;
 543 }
 544
 545 /*
 546  * Splits the PATH into parts.
 547  */
 548 static char **get_path_split(void)
 549 {
 550         char *p, **path, *envpath = getenv("PATH");
 551         int i, n = 0;
 552
 553         if (!envpath || !*envpath)
 554                 return NULL;
 555
 556         envpath = xstrdup(envpath);
 557         p = envpath;
 558         while (p) {
 559                 char *dir = p;
 560                 p = strchr(p, ';');
 561                 if (p) *p++ = '\0';
 562                 if (*dir) {     /* not earlier, catches series of ; */
 563                         ++n;
 564                 }
 565         }
 566         if (!n)
 567                 return NULL;
 568
 569         path = xmalloc((n+1)*sizeof(char *));
 570         p = envpath;
 571         i = 0;
 572         do {
 573                 if (*p)
 574                         path[i++] = xstrdup(p);
 575                 p = p+strlen(p)+1;
 576         } while (i < n);
 577         path[i] = NULL;
 578
 579         free(envpath);
 580
 581         return path;
 582 }
 583
 584 static void free_path_split(char **path)
 585 {
 586         char **p = path;
 587
 588         if (!path)
 589                 return;
 590
 591         while (*p)
 592                 free(*p++);
 593         free(path);
 594 }
 595
 596 /*
 597  * exe_only means that we only want to detect .exe files, but not scripts
 598  * (which do not have an extension)
 599  */
 600 static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 601 {
 602         char path[MAX_PATH];
 603         snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 604
 605         if (!isexe && access(path, F_OK) == 0)
 606                 return xstrdup(path);
 607         path[strlen(path)-4] = '\0';
 608         if ((!exe_only || isexe) && access(path, F_OK) == 0)
 609                 if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 610                         return xstrdup(path);
 611         return NULL;
 612 }
 613
 614 /*
 615  * Determines the absolute path of cmd using the split path in path.
 616  * If cmd contains a slash or backslash, no lookup is performed.
 617  */
 618 static char *path_lookup(const char *cmd, char **path, int exe_only)
 619 {
 620         char *prog = NULL;
 621         int len = strlen(cmd);
 622         int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 623
 624         if (strchr(cmd, '/') || strchr(cmd, '\\'))
 625                 prog = xstrdup(cmd);
 626
 627         while (!prog && *path)
 628                 prog = lookup_prog(*path++, cmd, isexe, exe_only);
 629
 630         return prog;
 631 }
 632
 633 static int env_compare(const void *a, const void *b)
 634 {
 635         char *const *ea = a;
 636         char *const *eb = b;
 637         return strcasecmp(*ea, *eb);
 638 }
 639
 640 struct pinfo_t {
 641         struct pinfo_t *next;
 642         pid_t pid;
 643         HANDLE proc;
 644 } pinfo_t;
 645 struct pinfo_t *pinfo = NULL;
 646 CRITICAL_SECTION pinfo_cs;
 647
 648 static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
 649                               const char *dir,
 650                               int prepend_cmd, int fhin, int fhout, int fherr)
 651 {
 652         STARTUPINFO si;
 653         PROCESS_INFORMATION pi;
 654         struct strbuf envblk, args;
 655         unsigned flags;
 656         BOOL ret;
 657
 658         /* Determine whether or not we are associated to a console */
 659         HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 660                         FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 661                         FILE_ATTRIBUTE_NORMAL, NULL);
 662         if (cons == INVALID_HANDLE_VALUE) {
 663                 /* There is no console associated with this process.
 664                  * Since the child is a console process, Windows
 665                  * would normally create a console window. But
 666                  * since we'll be redirecting std streams, we do
 667                  * not need the console.
 668                  * It is necessary to use DETACHED_PROCESS
 669                  * instead of CREATE_NO_WINDOW to make ssh
 670                  * recognize that it has no console.
 671                  */
 672                 flags = DETACHED_PROCESS;
 673         } else {
 674                 /* There is already a console. If we specified
 675                  * DETACHED_PROCESS here, too, Windows would
 676                  * disassociate the child from the console.
 677                  * The same is true for CREATE_NO_WINDOW.
 678                  * Go figure!
 679                  */
 680                 flags = 0;
 681                 CloseHandle(cons);
 682         }
 683         memset(&si, 0, sizeof(si));
 684         si.cb = sizeof(si);
 685         si.dwFlags = STARTF_USESTDHANDLES;
 686         si.hStdInput = (HANDLE) _get_osfhandle(fhin);
 687         si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
 688         si.hStdError = (HANDLE) _get_osfhandle(fherr);
 689
 690         /* concatenate argv, quoting args as we go */
 691         strbuf_init(&args, 0);
 692         if (prepend_cmd) {
 693                 char *quoted = (char *)quote_arg(cmd);
 694                 strbuf_addstr(&args, quoted);
 695                 if (quoted != cmd)
 696                         free(quoted);
 697         }
 698         for (; *argv; argv++) {
 699                 char *quoted = (char *)quote_arg(*argv);
 700                 if (*args.buf)
 701                         strbuf_addch(&args, ' ');
 702                 strbuf_addstr(&args, quoted);
 703                 if (quoted != *argv)
 704                         free(quoted);
 705         }
 706
 707         if (env) {
 708                 int count = 0;
 709                 char **e, **sorted_env;
 710
 711                 for (e = env; *e; e++)
 712                         count++;
 713
 714                 /* environment must be sorted */
 715                 sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 716                 memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 717                 qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 718
 719                 strbuf_init(&envblk, 0);
 720                 for (e = sorted_env; *e; e++) {
 721                         strbuf_addstr(&envblk, *e);
 722                         strbuf_addch(&envblk, '\0');
 723                 }
 724                 free(sorted_env);
 725         }
 726
 727         memset(&pi, 0, sizeof(pi));
 728         ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 729                 env ? envblk.buf : NULL, dir, &si, &pi);
 730
 731         if (env)
 732                 strbuf_release(&envblk);
 733         strbuf_release(&args);
 734
 735         if (!ret) {
 736                 errno = ENOENT;
 737                 return -1;
 738         }
 739         CloseHandle(pi.hThread);
 740
 741         /*
 742          * The process ID is the human-readable identifier of the process
 743          * that we want to present in log and error messages. The handle
 744          * is not useful for this purpose. But we cannot close it, either,
 745          * because it is not possible to turn a process ID into a process
 746          * handle after the process terminated.
 747          * Keep the handle in a list for waitpid.
 748          */
 749         EnterCriticalSection(&pinfo_cs);
 750         {
 751                 struct pinfo_t *info = xmalloc(sizeof(struct pinfo_t));
 752                 info->pid = pi.dwProcessId;
 753                 info->proc = pi.hProcess;
 754                 info->next = pinfo;
 755                 pinfo = info;
 756         }
 757         LeaveCriticalSection(&pinfo_cs);
 758
 759         return (pid_t)pi.dwProcessId;
 760 }
 761
 762 static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 763                            int prepend_cmd)
 764 {
 765         return mingw_spawnve_fd(cmd, argv, env, NULL, prepend_cmd, 0, 1, 2);
 766 }
 767
 768 pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
 769                      const char *dir,
 770                      int fhin, int fhout, int fherr)
 771 {
 772         pid_t pid;
 773         char **path = get_path_split();
 774         char *prog = path_lookup(cmd, path, 0);
 775
 776         if (!prog) {
 777                 errno = ENOENT;
 778                 pid = -1;
 779         }
 780         else {
 781                 const char *interpr = parse_interpreter(prog);
 782
 783                 if (interpr) {
 784                         const char *argv0 = argv[0];
 785                         char *iprog = path_lookup(interpr, path, 1);
 786                         argv[0] = prog;
 787                         if (!iprog) {
 788                                 errno = ENOENT;
 789                                 pid = -1;
 790                         }
 791                         else {
 792                                 pid = mingw_spawnve_fd(iprog, argv, env, dir, 1,
 793                                                        fhin, fhout, fherr);
 794                                 free(iprog);
 795                         }
 796                         argv[0] = argv0;
 797                 }
 798                 else
 799                         pid = mingw_spawnve_fd(prog, argv, env, dir, 0,
 800                                                fhin, fhout, fherr);
 801                 free(prog);
 802         }
 803         free_path_split(path);
 804         return pid;
 805 }
 806
 807 static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 808 {
 809         const char *interpr = parse_interpreter(cmd);
 810         char **path;
 811         char *prog;
 812         int pid = 0;
 813
 814         if (!interpr)
 815                 return 0;
 816         path = get_path_split();
 817         prog = path_lookup(interpr, path, 1);
 818         if (prog) {
 819                 int argc = 0;
 820                 const char **argv2;
 821                 while (argv[argc]) argc++;
 822                 argv2 = xmalloc(sizeof(*argv) * (argc+1));
 823                 argv2[0] = (char *)cmd; /* full path to the script file */
 824                 memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 825                 pid = mingw_spawnve(prog, argv2, env, 1);
 826                 if (pid >= 0) {
 827                         int status;
 828                         if (waitpid(pid, &status, 0) < 0)
 829                                 status = 255;
 830                         exit(status);
 831                 }
 832                 pid = 1;        /* indicate that we tried but failed */
 833                 free(prog);
 834                 free(argv2);
 835         }
 836         free_path_split(path);
 837         return pid;
 838 }
 839
 840 static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 841 {
 842         /* check if git_command is a shell script */
 843         if (!try_shell_exec(cmd, argv, (char **)env)) {
 844                 int pid, status;
 845
 846                 pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 847                 if (pid < 0)
 848                         return;
 849                 if (waitpid(pid, &status, 0) < 0)
 850                         status = 255;
 851                 exit(status);
 852         }
 853 }
 854
 855 void mingw_execvp(const char *cmd, char *const *argv)
 856 {
 857         char **path = get_path_split();
 858         char *prog = path_lookup(cmd, path, 0);
 859
 860         if (prog) {
 861                 mingw_execve(prog, argv, environ);
 862                 free(prog);
 863         } else
 864                 errno = ENOENT;
 865
 866         free_path_split(path);
 867 }
 868
 869 void mingw_execv(const char *cmd, char *const *argv)
 870 {
 871         mingw_execve(cmd, argv, environ);
 872 }
 873
 874 int mingw_kill(pid_t pid, int sig)
 875 {
 876         if (pid > 0 && sig == SIGTERM) {
 877                 HANDLE h = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
 878
 879                 if (TerminateProcess(h, -1)) {
 880                         CloseHandle(h);
 881                         return 0;
 882                 }
 883
 884                 errno = err_win_to_posix(GetLastError());
 885                 CloseHandle(h);
 886                 return -1;
 887         }
 888
 889         errno = EINVAL;
 890         return -1;
 891 }
 892
 893 static char **copy_environ(void)
 894 {
 895         char **env;
 896         int i = 0;
 897         while (environ[i])
 898                 i++;
 899         env = xmalloc((i+1)*sizeof(*env));
 900         for (i = 0; environ[i]; i++)
 901                 env[i] = xstrdup(environ[i]);
 902         env[i] = NULL;
 903         return env;
 904 }
 905
 906 void free_environ(char **env)
 907 {
 908         int i;
 909         for (i = 0; env[i]; i++)
 910                 free(env[i]);
 911         free(env);
 912 }
 913
 914 static int lookup_env(char **env, const char *name, size_t nmln)
 915 {
 916         int i;
 917
 918         for (i = 0; env[i]; i++) {
 919                 if (0 == strncmp(env[i], name, nmln)
 920                     && '=' == env[i][nmln])
 921                         /* matches */
 922                         return i;
 923         }
 924         return -1;
 925 }
 926
 927 /*
 928  * If name contains '=', then sets the variable, otherwise it unsets it
 929  */
 930 static char **env_setenv(char **env, const char *name)
 931 {
 932         char *eq = strchrnul(name, '=');
 933         int i = lookup_env(env, name, eq-name);
 934
 935         if (i < 0) {
 936                 if (*eq) {
 937                         for (i = 0; env[i]; i++)
 938                                 ;
 939                         env = xrealloc(env, (i+2)*sizeof(*env));
 940                         env[i] = xstrdup(name);
 941                         env[i+1] = NULL;
 942                 }
 943         }
 944         else {
 945                 free(env[i]);
 946                 if (*eq)
 947                         env[i] = xstrdup(name);
 948                 else
 949                         for (; env[i]; i++)
 950                                 env[i] = env[i+1];
 951         }
 952         return env;
 953 }
 954
 955 /*
 956  * Copies global environ and adjusts variables as specified by vars.
 957  */
 958 char **make_augmented_environ(const char *const *vars)
 959 {
 960         char **env = copy_environ();
 961
 962         while (*vars)
 963                 env = env_setenv(env, *vars++);
 964         return env;
 965 }
 966
 967 /*
 968  * Note, this isn't a complete replacement for getaddrinfo. It assumes
 969  * that service contains a numerical port, or that it it is null. It
 970  * does a simple search using gethostbyname, and returns one IPv4 host
 971  * if one was found.
 972  */
 973 static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
 974                                    const struct addrinfo *hints,
 975                                    struct addrinfo **res)
 976 {
 977         struct hostent *h = NULL;
 978         struct addrinfo *ai;
 979         struct sockaddr_in *sin;
 980
 981         if (node) {
 982                 h = gethostbyname(node);
 983                 if (!h)
 984                         return WSAGetLastError();
 985         }
 986
 987         ai = xmalloc(sizeof(struct addrinfo));
 988         *res = ai;
 989         ai->ai_flags = 0;
 990         ai->ai_family = AF_INET;
 991         ai->ai_socktype = hints ? hints->ai_socktype : 0;
 992         switch (ai->ai_socktype) {
 993         case SOCK_STREAM:
 994                 ai->ai_protocol = IPPROTO_TCP;
 995                 break;
 996         case SOCK_DGRAM:
 997                 ai->ai_protocol = IPPROTO_UDP;
 998                 break;
 999         default:
1000                 ai->ai_protocol = 0;
1001                 break;
1002         }
1003         ai->ai_addrlen = sizeof(struct sockaddr_in);
1004         if (hints && (hints->ai_flags & AI_CANONNAME))
1005                 ai->ai_canonname = h ? strdup(h->h_name) : NULL;
1006         else
1007                 ai->ai_canonname = NULL;
1008
1009         sin = xmalloc(ai->ai_addrlen);
1010         memset(sin, 0, ai->ai_addrlen);
1011         sin->sin_family = AF_INET;
1012         /* Note: getaddrinfo is supposed to allow service to be a string,
1013          * which should be looked up using getservbyname. This is
1014          * currently not implemented */
1015         if (service)
1016                 sin->sin_port = htons(atoi(service));
1017         if (h)
1018                 sin->sin_addr = *(struct in_addr *)h->h_addr;
1019         else if (hints && (hints->ai_flags & AI_PASSIVE))
1020                 sin->sin_addr.s_addr = INADDR_ANY;
1021         else
1022                 sin->sin_addr.s_addr = INADDR_LOOPBACK;
1023         ai->ai_addr = (struct sockaddr *)sin;
1024         ai->ai_next = 0;
1025         return 0;
1026 }
1027
1028 static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
1029 {
1030         free(res->ai_canonname);
1031         free(res->ai_addr);
1032         free(res);
1033 }
1034
1035 static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
1036                                    char *host, DWORD hostlen,
1037                                    char *serv, DWORD servlen, int flags)
1038 {
1039         const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
1040         if (sa->sa_family != AF_INET)
1041                 return EAI_FAMILY;
1042         if (!host && !serv)
1043                 return EAI_NONAME;
1044
1045         if (host && hostlen > 0) {
1046                 struct hostent *ent = NULL;
1047                 if (!(flags & NI_NUMERICHOST))
1048                         ent = gethostbyaddr((const char *)&sin->sin_addr,
1049                                             sizeof(sin->sin_addr), AF_INET);
1050
1051                 if (ent)
1052                         snprintf(host, hostlen, "%s", ent->h_name);
1053                 else if (flags & NI_NAMEREQD)
1054                         return EAI_NONAME;
1055                 else
1056                         snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
1057         }
1058
1059         if (serv && servlen > 0) {
1060                 struct servent *ent = NULL;
1061                 if (!(flags & NI_NUMERICSERV))
1062                         ent = getservbyport(sin->sin_port,
1063                                             flags & NI_DGRAM ? "udp" : "tcp");
1064
1065                 if (ent)
1066                         snprintf(serv, servlen, "%s", ent->s_name);
1067                 else
1068                         snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
1069         }
1070
1071         return 0;
1072 }
1073
1074 static HMODULE ipv6_dll = NULL;
1075 static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
1076 static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
1077                                       const struct addrinfo *hints,
1078                                       struct addrinfo **res);
1079 static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
1080                                       char *host, DWORD hostlen,
1081                                       char *serv, DWORD servlen, int flags);
1082 /*
1083  * gai_strerror is an inline function in the ws2tcpip.h header, so we
1084  * don't need to try to load that one dynamically.
1085  */
1086
1087 static void socket_cleanup(void)
1088 {
1089         WSACleanup();
1090         if (ipv6_dll)
1091                 FreeLibrary(ipv6_dll);
1092         ipv6_dll = NULL;
1093         ipv6_freeaddrinfo = freeaddrinfo_stub;
1094         ipv6_getaddrinfo = getaddrinfo_stub;
1095         ipv6_getnameinfo = getnameinfo_stub;
1096 }
1097
1098 static void ensure_socket_initialization(void)
1099 {
1100         WSADATA wsa;
1101         static int initialized = 0;
1102         const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
1103         const char **name;
1104
1105         if (initialized)
1106                 return;
1107
1108         if (WSAStartup(MAKEWORD(2,2), &wsa))
1109                 die("unable to initialize winsock subsystem, error %d",
1110                         WSAGetLastError());
1111
1112         for (name = libraries; *name; name++) {
1113                 ipv6_dll = LoadLibrary(*name);
1114                 if (!ipv6_dll)
1115                         continue;
1116
1117                 ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
1118                         GetProcAddress(ipv6_dll, "freeaddrinfo");
1119                 ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
1120                                                    const struct addrinfo *,
1121                                                    struct addrinfo **))
1122                         GetProcAddress(ipv6_dll, "getaddrinfo");
1123                 ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
1124                                                    socklen_t, char *, DWORD,
1125                                                    char *, DWORD, int))
1126                         GetProcAddress(ipv6_dll, "getnameinfo");
1127                 if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1128                         FreeLibrary(ipv6_dll);
1129                         ipv6_dll = NULL;
1130                 } else
1131                         break;
1132         }
1133         if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1134                 ipv6_freeaddrinfo = freeaddrinfo_stub;
1135                 ipv6_getaddrinfo = getaddrinfo_stub;
1136                 ipv6_getnameinfo = getnameinfo_stub;
1137         }
1138
1139         atexit(socket_cleanup);
1140         initialized = 1;
1141 }
1142
1143 #undef gethostbyname
1144 struct hostent *mingw_gethostbyname(const char *host)
1145 {
1146         ensure_socket_initialization();
1147         return gethostbyname(host);
1148 }
1149
1150 void mingw_freeaddrinfo(struct addrinfo *res)
1151 {
1152         ipv6_freeaddrinfo(res);
1153 }
1154
1155 int mingw_getaddrinfo(const char *node, const char *service,
1156                       const struct addrinfo *hints, struct addrinfo **res)
1157 {
1158         ensure_socket_initialization();
1159         return ipv6_getaddrinfo(node, service, hints, res);
1160 }
1161
1162 int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
1163                       char *host, DWORD hostlen, char *serv, DWORD servlen,
1164                       int flags)
1165 {
1166         ensure_socket_initialization();
1167         return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
1168 }
1169
1170 int mingw_socket(int domain, int type, int protocol)
1171 {
1172         int sockfd;
1173         SOCKET s;
1174
1175         ensure_socket_initialization();
1176         s = WSASocket(domain, type, protocol, NULL, 0, 0);
1177         if (s == INVALID_SOCKET) {
1178                 /*
1179                  * WSAGetLastError() values are regular BSD error codes
1180                  * biased by WSABASEERR.
1181                  * However, strerror() does not know about networking
1182                  * specific errors, which are values beginning at 38 or so.
1183                  * Therefore, we choose to leave the biased error code
1184                  * in errno so that _if_ someone looks up the code somewhere,
1185                  * then it is at least the number that are usually listed.
1186                  */
1187                 errno = WSAGetLastError();
1188                 return -1;
1189         }
1190         /* convert into a file descriptor */
1191         if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
1192                 closesocket(s);
1193                 return error("unable to make a socket file descriptor: %s",
1194                         strerror(errno));
1195         }
1196         return sockfd;
1197 }
1198
1199 #undef connect
1200 int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1201 {
1202         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1203         return connect(s, sa, sz);
1204 }
1205
1206 #undef bind
1207 int mingw_bind(int sockfd, struct sockaddr *sa, size_t sz)
1208 {
1209         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1210         return bind(s, sa, sz);
1211 }
1212
1213 #undef setsockopt
1214 int mingw_setsockopt(int sockfd, int lvl, int optname, void *optval, int optlen)
1215 {
1216         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1217         return setsockopt(s, lvl, optname, (const char*)optval, optlen);
1218 }
1219
1220 #undef listen
1221 int mingw_listen(int sockfd, int backlog)
1222 {
1223         SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1224         return listen(s, backlog);
1225 }
1226
1227 #undef accept
1228 int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
1229 {
1230         int sockfd2;
1231
1232         SOCKET s1 = (SOCKET)_get_osfhandle(sockfd1);
1233         SOCKET s2 = accept(s1, sa, sz);
1234
1235         /* convert into a file descriptor */
1236         if ((sockfd2 = _open_osfhandle(s2, O_RDWR|O_BINARY)) < 0) {
1237                 int err = errno;
1238                 closesocket(s2);
1239                 return error("unable to make a socket file descriptor: %s",
1240                         strerror(err));
1241         }
1242         return sockfd2;
1243 }
1244
1245 #undef rename
1246 int mingw_rename(const char *pold, const char *pnew)
1247 {
1248         DWORD attrs, gle;
1249         int tries = 0;
1250         static const int delay[] = { 0, 1, 10, 20, 40 };
1251
1252         /*
1253          * Try native rename() first to get errno right.
1254          * It is based on MoveFile(), which cannot overwrite existing files.
1255          */
1256         if (!rename(pold, pnew))
1257                 return 0;
1258         if (errno != EEXIST)
1259                 return -1;
1260 repeat:
1261         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1262                 return 0;
1263         /* TODO: translate more errors */
1264         gle = GetLastError();
1265         if (gle == ERROR_ACCESS_DENIED &&
1266             (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1267                 if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1268                         errno = EISDIR;
1269                         return -1;
1270                 }
1271                 if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1272                     SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1273                         if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1274                                 return 0;
1275                         gle = GetLastError();
1276                         /* revert file attributes on failure */
1277                         SetFileAttributes(pnew, attrs);
1278                 }
1279         }
1280         if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1281                 /*
1282                  * We assume that some other process had the source or
1283                  * destination file open at the wrong moment and retry.
1284                  * In order to give the other process a higher chance to
1285                  * complete its operation, we give up our time slice now.
1286                  * If we have to retry again, we do sleep a bit.
1287                  */
1288                 Sleep(delay[tries]);
1289                 tries++;
1290                 goto repeat;
1291         }
1292         errno = EACCES;
1293         return -1;
1294 }
1295
1296 /*
1297  * Note that this doesn't return the actual pagesize, but
1298  * the allocation granularity. If future Windows specific git code
1299  * needs the real getpagesize function, we need to find another solution.
1300  */
1301 int mingw_getpagesize(void)
1302 {
1303         SYSTEM_INFO si;
1304         GetSystemInfo(&si);
1305         return si.dwAllocationGranularity;
1306 }
1307
1308 struct passwd *getpwuid(int uid)
1309 {
1310         static char user_name[100];
1311         static struct passwd p;
1312
1313         DWORD len = sizeof(user_name);
1314         if (!GetUserName(user_name, &len))
1315                 return NULL;
1316         p.pw_name = user_name;
1317         p.pw_gecos = "unknown";
1318         p.pw_dir = NULL;
1319         return &p;
1320 }
1321
1322 static HANDLE timer_event;
1323 static HANDLE timer_thread;
1324 static int timer_interval;
1325 static int one_shot;
1326 static sig_handler_t timer_fn = SIG_DFL;
1327
1328 /* The timer works like this:
1329  * The thread, ticktack(), is a trivial routine that most of the time
1330  * only waits to receive the signal to terminate. The main thread tells
1331  * the thread to terminate by setting the timer_event to the signalled
1332  * state.
1333  * But ticktack() interrupts the wait state after the timer's interval
1334  * length to call the signal handler.
1335  */
1336
1337 static unsigned __stdcall ticktack(void *dummy)
1338 {
1339         while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1340                 if (timer_fn == SIG_DFL)
1341                         die("Alarm");
1342                 if (timer_fn != SIG_IGN)
1343                         timer_fn(SIGALRM);
1344                 if (one_shot)
1345                         break;
1346         }
1347         return 0;
1348 }
1349
1350 static int start_timer_thread(void)
1351 {
1352         timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1353         if (timer_event) {
1354                 timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1355                 if (!timer_thread )
1356                         return errno = ENOMEM,
1357                                 error("cannot start timer thread");
1358         } else
1359                 return errno = ENOMEM,
1360                         error("cannot allocate resources for timer");
1361         return 0;
1362 }
1363
1364 static void stop_timer_thread(void)
1365 {
1366         if (timer_event)
1367                 SetEvent(timer_event);  /* tell thread to terminate */
1368         if (timer_thread) {
1369                 int rc = WaitForSingleObject(timer_thread, 1000);
1370                 if (rc == WAIT_TIMEOUT)
1371                         error("timer thread did not terminate timely");
1372                 else if (rc != WAIT_OBJECT_0)
1373                         error("waiting for timer thread failed: %lu",
1374                               GetLastError());
1375                 CloseHandle(timer_thread);
1376         }
1377         if (timer_event)
1378                 CloseHandle(timer_event);
1379         timer_event = NULL;
1380         timer_thread = NULL;
1381 }
1382
1383 static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1384 {
1385         return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1386 }
1387
1388 int setitimer(int type, struct itimerval *in, struct itimerval *out)
1389 {
1390         static const struct timeval zero;
1391         static int atexit_done;
1392
1393         if (out != NULL)
1394                 return errno = EINVAL,
1395                         error("setitimer param 3 != NULL not implemented");
1396         if (!is_timeval_eq(&in->it_interval, &zero) &&
1397             !is_timeval_eq(&in->it_interval, &in->it_value))
1398                 return errno = EINVAL,
1399                         error("setitimer: it_interval must be zero or eq it_value");
1400
1401         if (timer_thread)
1402                 stop_timer_thread();
1403
1404         if (is_timeval_eq(&in->it_value, &zero) &&
1405             is_timeval_eq(&in->it_interval, &zero))
1406                 return 0;
1407
1408         timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1409         one_shot = is_timeval_eq(&in->it_interval, &zero);
1410         if (!atexit_done) {
1411                 atexit(stop_timer_thread);
1412                 atexit_done = 1;
1413         }
1414         return start_timer_thread();
1415 }
1416
1417 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1418 {
1419         if (sig != SIGALRM)
1420                 return errno = EINVAL,
1421                         error("sigaction only implemented for SIGALRM");
1422         if (out != NULL)
1423                 return errno = EINVAL,
1424                         error("sigaction: param 3 != NULL not implemented");
1425
1426         timer_fn = in->sa_handler;
1427         return 0;
1428 }
1429
1430 #undef signal
1431 sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1432 {
1433         sig_handler_t old = timer_fn;
1434         if (sig != SIGALRM)
1435                 return signal(sig, handler);
1436         timer_fn = handler;
1437         return old;
1438 }
1439
1440 static const char *make_backslash_path(const char *path)
1441 {
1442         static char buf[PATH_MAX + 1];
1443         char *c;
1444
1445         if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1446                 die("Too long path: %.*s", 60, path);
1447
1448         for (c = buf; *c; c++) {
1449                 if (*c == '/')
1450                         *c = '\\';
1451         }
1452         return buf;
1453 }
1454
1455 void mingw_open_html(const char *unixpath)
1456 {
1457         const char *htmlpath = make_backslash_path(unixpath);
1458         typedef HINSTANCE (WINAPI *T)(HWND, const char *,
1459                         const char *, const char *, const char *, INT);
1460         T ShellExecute;
1461         HMODULE shell32;
1462         int r;
1463
1464         shell32 = LoadLibrary("shell32.dll");
1465         if (!shell32)
1466                 die("cannot load shell32.dll");
1467         ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
1468         if (!ShellExecute)
1469                 die("cannot run browser");
1470
1471         printf("Launching default browser to display HTML ...\n");
1472         r = (int)ShellExecute(NULL, "open", htmlpath, NULL, "\\", SW_SHOWNORMAL);
1473         FreeLibrary(shell32);
1474         /* see the MSDN documentation referring to the result codes here */
1475         if (r <= 32) {
1476                 die("failed to launch browser for %.*s", MAX_PATH, unixpath);
1477         }
1478 }
1479
1480 int link(const char *oldpath, const char *newpath)
1481 {
1482         typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1483         static T create_hard_link = NULL;
1484         if (!create_hard_link) {
1485                 create_hard_link = (T) GetProcAddress(
1486                         GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1487                 if (!create_hard_link)
1488                         create_hard_link = (T)-1;
1489         }
1490         if (create_hard_link == (T)-1) {
1491                 errno = ENOSYS;
1492                 return -1;
1493         }
1494         if (!create_hard_link(newpath, oldpath, NULL)) {
1495                 errno = err_win_to_posix(GetLastError());
1496                 return -1;
1497         }
1498         return 0;
1499 }
1500
1501 char *getpass(const char *prompt)
1502 {
1503         struct strbuf buf = STRBUF_INIT;
1504
1505         fputs(prompt, stderr);
1506         for (;;) {
1507                 char c = _getch();
1508                 if (c == '\r' || c == '\n')
1509                         break;
1510                 strbuf_addch(&buf, c);
1511         }
1512         fputs("\n", stderr);
1513         return strbuf_detach(&buf, NULL);
1514 }
1515
1516 pid_t waitpid(pid_t pid, int *status, unsigned options)
1517 {
1518         HANDLE h = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
1519             FALSE, pid);
1520         if (!h) {
1521                 errno = ECHILD;
1522                 return -1;
1523         }
1524
1525         if (pid > 0 && options & WNOHANG) {
1526                 if (WAIT_OBJECT_0 != WaitForSingleObject(h, 0)) {
1527                         CloseHandle(h);
1528                         return 0;
1529                 }
1530                 options &= ~WNOHANG;
1531         }
1532
1533         if (options == 0) {
1534                 struct pinfo_t **ppinfo;
1535                 if (WaitForSingleObject(h, INFINITE) != WAIT_OBJECT_0) {
1536                         CloseHandle(h);
1537                         return 0;
1538                 }
1539
1540                 if (status)
1541                         GetExitCodeProcess(h, (LPDWORD)status);
1542
1543                 EnterCriticalSection(&pinfo_cs);
1544
1545                 ppinfo = &pinfo;
1546                 while (*ppinfo) {
1547                         struct pinfo_t *info = *ppinfo;
1548                         if (info->pid == pid) {
1549                                 CloseHandle(info->proc);
1550                                 *ppinfo = info->next;
1551                                 free(info);
1552                                 break;
1553                         }
1554                         ppinfo = &info->next;
1555                 }
1556
1557                 LeaveCriticalSection(&pinfo_cs);
1558
1559                 CloseHandle(h);
1560                 return pid;
1561         }
1562         CloseHandle(h);
1563
1564         errno = EINVAL;
1565         return -1;
1566 }