compat/mingw.c

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