7eed60db1b10cc303f37e1bf3307058af94b8f9d
   1#include "../git-compat-util.h"
   2#include "../strbuf.h"
   3
   4unsigned int _CRT_fmode = _O_BINARY;
   5
   6#undef open
   7int mingw_open (const char *filename, int oflags, ...)
   8{
   9        va_list args;
  10        unsigned mode;
  11        va_start(args, oflags);
  12        mode = va_arg(args, int);
  13        va_end(args);
  14
  15        if (!strcmp(filename, "/dev/null"))
  16                filename = "nul";
  17        int fd = open(filename, oflags, mode);
  18        if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
  19                DWORD attrs = GetFileAttributes(filename);
  20                if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
  21                        errno = EISDIR;
  22        }
  23        return fd;
  24}
  25
  26static inline time_t filetime_to_time_t(const FILETIME *ft)
  27{
  28        long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
  29        winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
  30        winTime /= 10000000;             /* Nano to seconds resolution */
  31        return (time_t)winTime;
  32}
  33
  34extern int _getdrive( void );
  35/* We keep the do_lstat code in a separate function to avoid recursion.
  36 * When a path ends with a slash, the stat will fail with ENOENT. In
  37 * this case, we strip the trailing slashes and stat again.
  38 */
  39static int do_lstat(const char *file_name, struct stat *buf)
  40{
  41        WIN32_FILE_ATTRIBUTE_DATA fdata;
  42
  43        if (GetFileAttributesExA(file_name, GetFileExInfoStandard, &fdata)) {
  44                int fMode = S_IREAD;
  45                if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
  46                        fMode |= S_IFDIR;
  47                else
  48                        fMode |= S_IFREG;
  49                if (!(fdata.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
  50                        fMode |= S_IWRITE;
  51
  52                buf->st_ino = 0;
  53                buf->st_gid = 0;
  54                buf->st_uid = 0;
  55                buf->st_nlink = 1;
  56                buf->st_mode = fMode;
  57                buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
  58                buf->st_dev = buf->st_rdev = (_getdrive() - 1);
  59                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
  60                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
  61                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
  62                errno = 0;
  63                return 0;
  64        }
  65
  66        switch (GetLastError()) {
  67        case ERROR_ACCESS_DENIED:
  68        case ERROR_SHARING_VIOLATION:
  69        case ERROR_LOCK_VIOLATION:
  70        case ERROR_SHARING_BUFFER_EXCEEDED:
  71                errno = EACCES;
  72                break;
  73        case ERROR_BUFFER_OVERFLOW:
  74                errno = ENAMETOOLONG;
  75                break;
  76        case ERROR_NOT_ENOUGH_MEMORY:
  77                errno = ENOMEM;
  78                break;
  79        default:
  80                errno = ENOENT;
  81                break;
  82        }
  83        return -1;
  84}
  85
  86/* We provide our own lstat/fstat functions, since the provided
  87 * lstat/fstat functions are so slow. These stat functions are
  88 * tailored for Git's usage (read: fast), and are not meant to be
  89 * complete. Note that Git stat()s are redirected to mingw_lstat()
  90 * too, since Windows doesn't really handle symlinks that well.
  91 */
  92int mingw_lstat(const char *file_name, struct stat *buf)
  93{
  94        int namelen;
  95        static char alt_name[PATH_MAX];
  96
  97        if (!do_lstat(file_name, buf))
  98                return 0;
  99
 100        /* if file_name ended in a '/', Windows returned ENOENT;
 101         * try again without trailing slashes
 102         */
 103        if (errno != ENOENT)
 104                return -1;
 105
 106        namelen = strlen(file_name);
 107        if (namelen && file_name[namelen-1] != '/')
 108                return -1;
 109        while (namelen && file_name[namelen-1] == '/')
 110                --namelen;
 111        if (!namelen || namelen >= PATH_MAX)
 112                return -1;
 113
 114        memcpy(alt_name, file_name, namelen);
 115        alt_name[namelen] = 0;
 116        return do_lstat(alt_name, buf);
 117}
 118
 119#undef fstat
 120int mingw_fstat(int fd, struct stat *buf)
 121{
 122        HANDLE fh = (HANDLE)_get_osfhandle(fd);
 123        BY_HANDLE_FILE_INFORMATION fdata;
 124
 125        if (fh == INVALID_HANDLE_VALUE) {
 126                errno = EBADF;
 127                return -1;
 128        }
 129        /* direct non-file handles to MS's fstat() */
 130        if (GetFileType(fh) != FILE_TYPE_DISK)
 131                return fstat(fd, buf);
 132
 133        if (GetFileInformationByHandle(fh, &fdata)) {
 134                int fMode = S_IREAD;
 135                if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
 136                        fMode |= S_IFDIR;
 137                else
 138                        fMode |= S_IFREG;
 139                if (!(fdata.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 140                        fMode |= S_IWRITE;
 141
 142                buf->st_ino = 0;
 143                buf->st_gid = 0;
 144                buf->st_uid = 0;
 145                buf->st_nlink = 1;
 146                buf->st_mode = fMode;
 147                buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
 148                buf->st_dev = buf->st_rdev = (_getdrive() - 1);
 149                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 150                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 151                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 152                return 0;
 153        }
 154        errno = EBADF;
 155        return -1;
 156}
 157
 158static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 159{
 160        long long winTime = t * 10000000LL + 116444736000000000LL;
 161        ft->dwLowDateTime = winTime;
 162        ft->dwHighDateTime = winTime >> 32;
 163}
 164
 165int mingw_utime (const char *file_name, const struct utimbuf *times)
 166{
 167        FILETIME mft, aft;
 168        int fh, rc;
 169
 170        /* must have write permission */
 171        if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
 172                return -1;
 173
 174        time_t_to_filetime(times->modtime, &mft);
 175        time_t_to_filetime(times->actime, &aft);
 176        if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 177                errno = EINVAL;
 178                rc = -1;
 179        } else
 180                rc = 0;
 181        close(fh);
 182        return rc;
 183}
 184
 185unsigned int sleep (unsigned int seconds)
 186{
 187        Sleep(seconds*1000);
 188        return 0;
 189}
 190
 191int mkstemp(char *template)
 192{
 193        char *filename = mktemp(template);
 194        if (filename == NULL)
 195                return -1;
 196        return open(filename, O_RDWR | O_CREAT, 0600);
 197}
 198
 199int gettimeofday(struct timeval *tv, void *tz)
 200{
 201        SYSTEMTIME st;
 202        struct tm tm;
 203        GetSystemTime(&st);
 204        tm.tm_year = st.wYear-1900;
 205        tm.tm_mon = st.wMonth-1;
 206        tm.tm_mday = st.wDay;
 207        tm.tm_hour = st.wHour;
 208        tm.tm_min = st.wMinute;
 209        tm.tm_sec = st.wSecond;
 210        tv->tv_sec = tm_to_time_t(&tm);
 211        if (tv->tv_sec < 0)
 212                return -1;
 213        tv->tv_usec = st.wMilliseconds*1000;
 214        return 0;
 215}
 216
 217int pipe(int filedes[2])
 218{
 219        int fd;
 220        HANDLE h[2], parent;
 221
 222        if (_pipe(filedes, 8192, 0) < 0)
 223                return -1;
 224
 225        parent = GetCurrentProcess();
 226
 227        if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[0]),
 228                        parent, &h[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 229                close(filedes[0]);
 230                close(filedes[1]);
 231                return -1;
 232        }
 233        if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[1]),
 234                        parent, &h[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
 235                close(filedes[0]);
 236                close(filedes[1]);
 237                CloseHandle(h[0]);
 238                return -1;
 239        }
 240        fd = _open_osfhandle((int)h[0], O_NOINHERIT);
 241        if (fd < 0) {
 242                close(filedes[0]);
 243                close(filedes[1]);
 244                CloseHandle(h[0]);
 245                CloseHandle(h[1]);
 246                return -1;
 247        }
 248        close(filedes[0]);
 249        filedes[0] = fd;
 250        fd = _open_osfhandle((int)h[1], O_NOINHERIT);
 251        if (fd < 0) {
 252                close(filedes[0]);
 253                close(filedes[1]);
 254                CloseHandle(h[1]);
 255                return -1;
 256        }
 257        close(filedes[1]);
 258        filedes[1] = fd;
 259        return 0;
 260}
 261
 262int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 263{
 264        int i, pending;
 265
 266        if (timeout >= 0) {
 267                if (nfds == 0) {
 268                        Sleep(timeout);
 269                        return 0;
 270                }
 271                return errno = EINVAL, error("poll timeout not supported");
 272        }
 273
 274        /* When there is only one fd to wait for, then we pretend that
 275         * input is available and let the actual wait happen when the
 276         * caller invokes read().
 277         */
 278        if (nfds == 1) {
 279                if (!(ufds[0].events & POLLIN))
 280                        return errno = EINVAL, error("POLLIN not set");
 281                ufds[0].revents = POLLIN;
 282                return 0;
 283        }
 284
 285repeat:
 286        pending = 0;
 287        for (i = 0; i < nfds; i++) {
 288                DWORD avail = 0;
 289                HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 290                if (h == INVALID_HANDLE_VALUE)
 291                        return -1;      /* errno was set */
 292
 293                if (!(ufds[i].events & POLLIN))
 294                        return errno = EINVAL, error("POLLIN not set");
 295
 296                /* this emulation works only for pipes */
 297                if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 298                        int err = GetLastError();
 299                        if (err == ERROR_BROKEN_PIPE) {
 300                                ufds[i].revents = POLLHUP;
 301                                pending++;
 302                        } else {
 303                                errno = EINVAL;
 304                                return error("PeekNamedPipe failed,"
 305                                        " GetLastError: %u", err);
 306                        }
 307                } else if (avail) {
 308                        ufds[i].revents = POLLIN;
 309                        pending++;
 310                } else
 311                        ufds[i].revents = 0;
 312        }
 313        if (!pending) {
 314                /* The only times that we spin here is when the process
 315                 * that is connected through the pipes is waiting for
 316                 * its own input data to become available. But since
 317                 * the process (pack-objects) is itself CPU intensive,
 318                 * it will happily pick up the time slice that we are
 319                 * relinguishing here.
 320                 */
 321                Sleep(0);
 322                goto repeat;
 323        }
 324        return 0;
 325}
 326
 327struct tm *gmtime_r(const time_t *timep, struct tm *result)
 328{
 329        /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 330        memcpy(result, gmtime(timep), sizeof(struct tm));
 331        return result;
 332}
 333
 334struct tm *localtime_r(const time_t *timep, struct tm *result)
 335{
 336        /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 337        memcpy(result, localtime(timep), sizeof(struct tm));
 338        return result;
 339}
 340
 341#undef getcwd
 342char *mingw_getcwd(char *pointer, int len)
 343{
 344        int i;
 345        char *ret = getcwd(pointer, len);
 346        if (!ret)
 347                return ret;
 348        for (i = 0; pointer[i]; i++)
 349                if (pointer[i] == '\\')
 350                        pointer[i] = '/';
 351        return ret;
 352}
 353
 354#undef getenv
 355char *mingw_getenv(const char *name)
 356{
 357        char *result = getenv(name);
 358        if (!result && !strcmp(name, "TMPDIR")) {
 359                /* on Windows it is TMP and TEMP */
 360                result = getenv("TMP");
 361                if (!result)
 362                        result = getenv("TEMP");
 363        }
 364        return result;
 365}
 366
 367/*
 368 * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 369 * (Parsing C++ Command-Line Arguments)
 370 */
 371static const char *quote_arg(const char *arg)
 372{
 373        /* count chars to quote */
 374        int len = 0, n = 0;
 375        int force_quotes = 0;
 376        char *q, *d;
 377        const char *p = arg;
 378        if (!*p) force_quotes = 1;
 379        while (*p) {
 380                if (isspace(*p) || *p == '*' || *p == '?' || *p == '{')
 381                        force_quotes = 1;
 382                else if (*p == '"')
 383                        n++;
 384                else if (*p == '\\') {
 385                        int count = 0;
 386                        while (*p == '\\') {
 387                                count++;
 388                                p++;
 389                                len++;
 390                        }
 391                        if (*p == '"')
 392                                n += count*2 + 1;
 393                        continue;
 394                }
 395                len++;
 396                p++;
 397        }
 398        if (!force_quotes && n == 0)
 399                return arg;
 400
 401        /* insert \ where necessary */
 402        d = q = xmalloc(len+n+3);
 403        *d++ = '"';
 404        while (*arg) {
 405                if (*arg == '"')
 406                        *d++ = '\\';
 407                else if (*arg == '\\') {
 408                        int count = 0;
 409                        while (*arg == '\\') {
 410                                count++;
 411                                *d++ = *arg++;
 412                        }
 413                        if (*arg == '"') {
 414                                while (count-- > 0)
 415                                        *d++ = '\\';
 416                                *d++ = '\\';
 417                        }
 418                }
 419                *d++ = *arg++;
 420        }
 421        *d++ = '"';
 422        *d++ = 0;
 423        return q;
 424}
 425
 426static const char *parse_interpreter(const char *cmd)
 427{
 428        static char buf[100];
 429        char *p, *opt;
 430        int n, fd;
 431
 432        /* don't even try a .exe */
 433        n = strlen(cmd);
 434        if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 435                return NULL;
 436
 437        fd = open(cmd, O_RDONLY);
 438        if (fd < 0)
 439                return NULL;
 440        n = read(fd, buf, sizeof(buf)-1);
 441        close(fd);
 442        if (n < 4)      /* at least '#!/x' and not error */
 443                return NULL;
 444
 445        if (buf[0] != '#' || buf[1] != '!')
 446                return NULL;
 447        buf[n] = '\0';
 448        p = strchr(buf, '\n');
 449        if (!p)
 450                return NULL;
 451
 452        *p = '\0';
 453        if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 454                return NULL;
 455        /* strip options */
 456        if ((opt = strchr(p+1, ' ')))
 457                *opt = '\0';
 458        return p+1;
 459}
 460
 461/*
 462 * Splits the PATH into parts.
 463 */
 464static char **get_path_split(void)
 465{
 466        char *p, **path, *envpath = getenv("PATH");
 467        int i, n = 0;
 468
 469        if (!envpath || !*envpath)
 470                return NULL;
 471
 472        envpath = xstrdup(envpath);
 473        p = envpath;
 474        while (p) {
 475                char *dir = p;
 476                p = strchr(p, ';');
 477                if (p) *p++ = '\0';
 478                if (*dir) {     /* not earlier, catches series of ; */
 479                        ++n;
 480                }
 481        }
 482        if (!n)
 483                return NULL;
 484
 485        path = xmalloc((n+1)*sizeof(char*));
 486        p = envpath;
 487        i = 0;
 488        do {
 489                if (*p)
 490                        path[i++] = xstrdup(p);
 491                p = p+strlen(p)+1;
 492        } while (i < n);
 493        path[i] = NULL;
 494
 495        free(envpath);
 496
 497        return path;
 498}
 499
 500static void free_path_split(char **path)
 501{
 502        if (!path)
 503                return;
 504
 505        char **p = path;
 506        while (*p)
 507                free(*p++);
 508        free(path);
 509}
 510
 511/*
 512 * exe_only means that we only want to detect .exe files, but not scripts
 513 * (which do not have an extension)
 514 */
 515static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 516{
 517        char path[MAX_PATH];
 518        snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 519
 520        if (!isexe && access(path, F_OK) == 0)
 521                return xstrdup(path);
 522        path[strlen(path)-4] = '\0';
 523        if ((!exe_only || isexe) && access(path, F_OK) == 0)
 524                if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 525                        return xstrdup(path);
 526        return NULL;
 527}
 528
 529/*
 530 * Determines the absolute path of cmd using the the split path in path.
 531 * If cmd contains a slash or backslash, no lookup is performed.
 532 */
 533static char *path_lookup(const char *cmd, char **path, int exe_only)
 534{
 535        char *prog = NULL;
 536        int len = strlen(cmd);
 537        int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 538
 539        if (strchr(cmd, '/') || strchr(cmd, '\\'))
 540                prog = xstrdup(cmd);
 541
 542        while (!prog && *path)
 543                prog = lookup_prog(*path++, cmd, isexe, exe_only);
 544
 545        return prog;
 546}
 547
 548static int env_compare(const void *a, const void *b)
 549{
 550        char *const *ea = a;
 551        char *const *eb = b;
 552        return strcasecmp(*ea, *eb);
 553}
 554
 555static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 556                           int prepend_cmd)
 557{
 558        STARTUPINFO si;
 559        PROCESS_INFORMATION pi;
 560        struct strbuf envblk, args;
 561        unsigned flags;
 562        BOOL ret;
 563
 564        /* Determine whether or not we are associated to a console */
 565        HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 566                        FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 567                        FILE_ATTRIBUTE_NORMAL, NULL);
 568        if (cons == INVALID_HANDLE_VALUE) {
 569                /* There is no console associated with this process.
 570                 * Since the child is a console process, Windows
 571                 * would normally create a console window. But
 572                 * since we'll be redirecting std streams, we do
 573                 * not need the console.
 574                 */
 575                flags = CREATE_NO_WINDOW;
 576        } else {
 577                /* There is already a console. If we specified
 578                 * CREATE_NO_WINDOW here, too, Windows would
 579                 * disassociate the child from the console.
 580                 * Go figure!
 581                 */
 582                flags = 0;
 583                CloseHandle(cons);
 584        }
 585        memset(&si, 0, sizeof(si));
 586        si.cb = sizeof(si);
 587        si.dwFlags = STARTF_USESTDHANDLES;
 588        si.hStdInput = (HANDLE) _get_osfhandle(0);
 589        si.hStdOutput = (HANDLE) _get_osfhandle(1);
 590        si.hStdError = (HANDLE) _get_osfhandle(2);
 591
 592        /* concatenate argv, quoting args as we go */
 593        strbuf_init(&args, 0);
 594        if (prepend_cmd) {
 595                char *quoted = (char *)quote_arg(cmd);
 596                strbuf_addstr(&args, quoted);
 597                if (quoted != cmd)
 598                        free(quoted);
 599        }
 600        for (; *argv; argv++) {
 601                char *quoted = (char *)quote_arg(*argv);
 602                if (*args.buf)
 603                        strbuf_addch(&args, ' ');
 604                strbuf_addstr(&args, quoted);
 605                if (quoted != *argv)
 606                        free(quoted);
 607        }
 608
 609        if (env) {
 610                int count = 0;
 611                char **e, **sorted_env;
 612
 613                for (e = env; *e; e++)
 614                        count++;
 615
 616                /* environment must be sorted */
 617                sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 618                memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 619                qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 620
 621                strbuf_init(&envblk, 0);
 622                for (e = sorted_env; *e; e++) {
 623                        strbuf_addstr(&envblk, *e);
 624                        strbuf_addch(&envblk, '\0');
 625                }
 626                free(sorted_env);
 627        }
 628
 629        memset(&pi, 0, sizeof(pi));
 630        ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 631                env ? envblk.buf : NULL, NULL, &si, &pi);
 632
 633        if (env)
 634                strbuf_release(&envblk);
 635        strbuf_release(&args);
 636
 637        if (!ret) {
 638                errno = ENOENT;
 639                return -1;
 640        }
 641        CloseHandle(pi.hThread);
 642        return (pid_t)pi.hProcess;
 643}
 644
 645pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
 646{
 647        pid_t pid;
 648        char **path = get_path_split();
 649        char *prog = path_lookup(cmd, path, 0);
 650
 651        if (!prog) {
 652                errno = ENOENT;
 653                pid = -1;
 654        }
 655        else {
 656                const char *interpr = parse_interpreter(prog);
 657
 658                if (interpr) {
 659                        const char *argv0 = argv[0];
 660                        char *iprog = path_lookup(interpr, path, 1);
 661                        argv[0] = prog;
 662                        if (!iprog) {
 663                                errno = ENOENT;
 664                                pid = -1;
 665                        }
 666                        else {
 667                                pid = mingw_spawnve(iprog, argv, env, 1);
 668                                free(iprog);
 669                        }
 670                        argv[0] = argv0;
 671                }
 672                else
 673                        pid = mingw_spawnve(prog, argv, env, 0);
 674                free(prog);
 675        }
 676        free_path_split(path);
 677        return pid;
 678}
 679
 680static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 681{
 682        const char *interpr = parse_interpreter(cmd);
 683        char **path;
 684        char *prog;
 685        int pid = 0;
 686
 687        if (!interpr)
 688                return 0;
 689        path = get_path_split();
 690        prog = path_lookup(interpr, path, 1);
 691        if (prog) {
 692                int argc = 0;
 693                const char **argv2;
 694                while (argv[argc]) argc++;
 695                argv2 = xmalloc(sizeof(*argv) * (argc+1));
 696                argv2[0] = (char *)cmd; /* full path to the script file */
 697                memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 698                pid = mingw_spawnve(prog, argv2, env, 1);
 699                if (pid >= 0) {
 700                        int status;
 701                        if (waitpid(pid, &status, 0) < 0)
 702                                status = 255;
 703                        exit(status);
 704                }
 705                pid = 1;        /* indicate that we tried but failed */
 706                free(prog);
 707                free(argv2);
 708        }
 709        free_path_split(path);
 710        return pid;
 711}
 712
 713static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 714{
 715        /* check if git_command is a shell script */
 716        if (!try_shell_exec(cmd, argv, (char **)env)) {
 717                int pid, status;
 718
 719                pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 720                if (pid < 0)
 721                        return;
 722                if (waitpid(pid, &status, 0) < 0)
 723                        status = 255;
 724                exit(status);
 725        }
 726}
 727
 728void mingw_execvp(const char *cmd, char *const *argv)
 729{
 730        char **path = get_path_split();
 731        char *prog = path_lookup(cmd, path, 0);
 732
 733        if (prog) {
 734                mingw_execve(prog, argv, environ);
 735                free(prog);
 736        } else
 737                errno = ENOENT;
 738
 739        free_path_split(path);
 740}
 741
 742char **copy_environ()
 743{
 744        char **env;
 745        int i = 0;
 746        while (environ[i])
 747                i++;
 748        env = xmalloc((i+1)*sizeof(*env));
 749        for (i = 0; environ[i]; i++)
 750                env[i] = xstrdup(environ[i]);
 751        env[i] = NULL;
 752        return env;
 753}
 754
 755void free_environ(char **env)
 756{
 757        int i;
 758        for (i = 0; env[i]; i++)
 759                free(env[i]);
 760        free(env);
 761}
 762
 763static int lookup_env(char **env, const char *name, size_t nmln)
 764{
 765        int i;
 766
 767        for (i = 0; env[i]; i++) {
 768                if (0 == strncmp(env[i], name, nmln)
 769                    && '=' == env[i][nmln])
 770                        /* matches */
 771                        return i;
 772        }
 773        return -1;
 774}
 775
 776/*
 777 * If name contains '=', then sets the variable, otherwise it unsets it
 778 */
 779char **env_setenv(char **env, const char *name)
 780{
 781        char *eq = strchrnul(name, '=');
 782        int i = lookup_env(env, name, eq-name);
 783
 784        if (i < 0) {
 785                if (*eq) {
 786                        for (i = 0; env[i]; i++)
 787                                ;
 788                        env = xrealloc(env, (i+2)*sizeof(*env));
 789                        env[i] = xstrdup(name);
 790                        env[i+1] = NULL;
 791                }
 792        }
 793        else {
 794                free(env[i]);
 795                if (*eq)
 796                        env[i] = xstrdup(name);
 797                else
 798                        for (; env[i]; i++)
 799                                env[i] = env[i+1];
 800        }
 801        return env;
 802}
 803
 804/* this is the first function to call into WS_32; initialize it */
 805#undef gethostbyname
 806struct hostent *mingw_gethostbyname(const char *host)
 807{
 808        WSADATA wsa;
 809
 810        if (WSAStartup(MAKEWORD(2,2), &wsa))
 811                die("unable to initialize winsock subsystem, error %d",
 812                        WSAGetLastError());
 813        atexit((void(*)(void)) WSACleanup);
 814        return gethostbyname(host);
 815}
 816
 817int mingw_socket(int domain, int type, int protocol)
 818{
 819        int sockfd;
 820        SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
 821        if (s == INVALID_SOCKET) {
 822                /*
 823                 * WSAGetLastError() values are regular BSD error codes
 824                 * biased by WSABASEERR.
 825                 * However, strerror() does not know about networking
 826                 * specific errors, which are values beginning at 38 or so.
 827                 * Therefore, we choose to leave the biased error code
 828                 * in errno so that _if_ someone looks up the code somewhere,
 829                 * then it is at least the number that are usually listed.
 830                 */
 831                errno = WSAGetLastError();
 832                return -1;
 833        }
 834        /* convert into a file descriptor */
 835        if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
 836                closesocket(s);
 837                return error("unable to make a socket file descriptor: %s",
 838                        strerror(errno));
 839        }
 840        return sockfd;
 841}
 842
 843#undef connect
 844int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
 845{
 846        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
 847        return connect(s, sa, sz);
 848}
 849
 850#undef rename
 851int mingw_rename(const char *pold, const char *pnew)
 852{
 853        /*
 854         * Try native rename() first to get errno right.
 855         * It is based on MoveFile(), which cannot overwrite existing files.
 856         */
 857        if (!rename(pold, pnew))
 858                return 0;
 859        if (errno != EEXIST)
 860                return -1;
 861        if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
 862                return 0;
 863        /* TODO: translate more errors */
 864        if (GetLastError() == ERROR_ACCESS_DENIED) {
 865                DWORD attrs = GetFileAttributes(pnew);
 866                if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY)) {
 867                        errno = EISDIR;
 868                        return -1;
 869                }
 870        }
 871        errno = EACCES;
 872        return -1;
 873}
 874
 875struct passwd *getpwuid(int uid)
 876{
 877        static char user_name[100];
 878        static struct passwd p;
 879
 880        DWORD len = sizeof(user_name);
 881        if (!GetUserName(user_name, &len))
 882                return NULL;
 883        p.pw_name = user_name;
 884        p.pw_gecos = "unknown";
 885        p.pw_dir = NULL;
 886        return &p;
 887}
 888
 889static HANDLE timer_event;
 890static HANDLE timer_thread;
 891static int timer_interval;
 892static int one_shot;
 893static sig_handler_t timer_fn = SIG_DFL;
 894
 895/* The timer works like this:
 896 * The thread, ticktack(), is a trivial routine that most of the time
 897 * only waits to receive the signal to terminate. The main thread tells
 898 * the thread to terminate by setting the timer_event to the signalled
 899 * state.
 900 * But ticktack() interrupts the wait state after the timer's interval
 901 * length to call the signal handler.
 902 */
 903
 904static __stdcall unsigned ticktack(void *dummy)
 905{
 906        while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
 907                if (timer_fn == SIG_DFL)
 908                        die("Alarm");
 909                if (timer_fn != SIG_IGN)
 910                        timer_fn(SIGALRM);
 911                if (one_shot)
 912                        break;
 913        }
 914        return 0;
 915}
 916
 917static int start_timer_thread(void)
 918{
 919        timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
 920        if (timer_event) {
 921                timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
 922                if (!timer_thread )
 923                        return errno = ENOMEM,
 924                                error("cannot start timer thread");
 925        } else
 926                return errno = ENOMEM,
 927                        error("cannot allocate resources for timer");
 928        return 0;
 929}
 930
 931static void stop_timer_thread(void)
 932{
 933        if (timer_event)
 934                SetEvent(timer_event);  /* tell thread to terminate */
 935        if (timer_thread) {
 936                int rc = WaitForSingleObject(timer_thread, 1000);
 937                if (rc == WAIT_TIMEOUT)
 938                        error("timer thread did not terminate timely");
 939                else if (rc != WAIT_OBJECT_0)
 940                        error("waiting for timer thread failed: %lu",
 941                              GetLastError());
 942                CloseHandle(timer_thread);
 943        }
 944        if (timer_event)
 945                CloseHandle(timer_event);
 946        timer_event = NULL;
 947        timer_thread = NULL;
 948}
 949
 950static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
 951{
 952        return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
 953}
 954
 955int setitimer(int type, struct itimerval *in, struct itimerval *out)
 956{
 957        static const struct timeval zero;
 958        static int atexit_done;
 959
 960        if (out != NULL)
 961                return errno = EINVAL,
 962                        error("setitimer param 3 != NULL not implemented");
 963        if (!is_timeval_eq(&in->it_interval, &zero) &&
 964            !is_timeval_eq(&in->it_interval, &in->it_value))
 965                return errno = EINVAL,
 966                        error("setitimer: it_interval must be zero or eq it_value");
 967
 968        if (timer_thread)
 969                stop_timer_thread();
 970
 971        if (is_timeval_eq(&in->it_value, &zero) &&
 972            is_timeval_eq(&in->it_interval, &zero))
 973                return 0;
 974
 975        timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
 976        one_shot = is_timeval_eq(&in->it_interval, &zero);
 977        if (!atexit_done) {
 978                atexit(stop_timer_thread);
 979                atexit_done = 1;
 980        }
 981        return start_timer_thread();
 982}
 983
 984int sigaction(int sig, struct sigaction *in, struct sigaction *out)
 985{
 986        if (sig != SIGALRM)
 987                return errno = EINVAL,
 988                        error("sigaction only implemented for SIGALRM");
 989        if (out != NULL)
 990                return errno = EINVAL,
 991                        error("sigaction: param 3 != NULL not implemented");
 992
 993        timer_fn = in->sa_handler;
 994        return 0;
 995}
 996
 997#undef signal
 998sig_handler_t mingw_signal(int sig, sig_handler_t handler)
 999{
1000        if (sig != SIGALRM)
1001                return signal(sig, handler);
1002        sig_handler_t old = timer_fn;
1003        timer_fn = handler;
1004        return old;
1005}
1006
1007static const char *make_backslash_path(const char *path)
1008{
1009        static char buf[PATH_MAX + 1];
1010        char *c;
1011
1012        if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1013                die("Too long path: %.*s", 60, path);
1014
1015        for (c = buf; *c; c++) {
1016                if (*c == '/')
1017                        *c = '\\';
1018        }
1019        return buf;
1020}
1021
1022void mingw_open_html(const char *unixpath)
1023{
1024        const char *htmlpath = make_backslash_path(unixpath);
1025        printf("Launching default browser to display HTML ...\n");
1026        ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1027}