Andrew's git / gitweb.git / compat/mingw.c
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compat / mingw.con commit Windows: avoid the "dup dance" when spawning a child process (75301f9)
   1#include "../git-compat-util.h"
   2#include "win32.h"
   3#include <conio.h>
   4#include "../strbuf.h"
   5
   6static 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
 120int 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 (!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
 143static inline time_t filetime_to_time_t(const FILETIME *ft)
 144{
 145        long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 146        winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
 147        winTime /= 10000000;             /* Nano to seconds resolution */
 148        return (time_t)winTime;
 149}
 150
 151/* We keep the do_lstat code in a separate function to avoid recursion.
 152 * When a path ends with a slash, the stat will fail with ENOENT. In
 153 * this case, we strip the trailing slashes and stat again.
 154 */
 155static int do_lstat(const char *file_name, struct stat *buf)
 156{
 157        WIN32_FILE_ATTRIBUTE_DATA fdata;
 158
 159        if (!(errno = get_file_attr(file_name, &fdata))) {
 160                buf->st_ino = 0;
 161                buf->st_gid = 0;
 162                buf->st_uid = 0;
 163                buf->st_nlink = 1;
 164                buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 165                buf->st_size = fdata.nFileSizeLow |
 166                        (((off_t)fdata.nFileSizeHigh)<<32);
 167                buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 168                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 169                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 170                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 171                return 0;
 172        }
 173        return -1;
 174}
 175
 176/* We provide our own lstat/fstat functions, since the provided
 177 * lstat/fstat functions are so slow. These stat functions are
 178 * tailored for Git's usage (read: fast), and are not meant to be
 179 * complete. Note that Git stat()s are redirected to mingw_lstat()
 180 * too, since Windows doesn't really handle symlinks that well.
 181 */
 182int mingw_lstat(const char *file_name, struct stat *buf)
 183{
 184        int namelen;
 185        static char alt_name[PATH_MAX];
 186
 187        if (!do_lstat(file_name, buf))
 188                return 0;
 189
 190        /* if file_name ended in a '/', Windows returned ENOENT;
 191         * try again without trailing slashes
 192         */
 193        if (errno != ENOENT)
 194                return -1;
 195
 196        namelen = strlen(file_name);
 197        if (namelen && file_name[namelen-1] != '/')
 198                return -1;
 199        while (namelen && file_name[namelen-1] == '/')
 200                --namelen;
 201        if (!namelen || namelen >= PATH_MAX)
 202                return -1;
 203
 204        memcpy(alt_name, file_name, namelen);
 205        alt_name[namelen] = 0;
 206        return do_lstat(alt_name, buf);
 207}
 208
 209#undef fstat
 210int mingw_fstat(int fd, struct stat *buf)
 211{
 212        HANDLE fh = (HANDLE)_get_osfhandle(fd);
 213        BY_HANDLE_FILE_INFORMATION fdata;
 214
 215        if (fh == INVALID_HANDLE_VALUE) {
 216                errno = EBADF;
 217                return -1;
 218        }
 219        /* direct non-file handles to MS's fstat() */
 220        if (GetFileType(fh) != FILE_TYPE_DISK)
 221                return _fstati64(fd, buf);
 222
 223        if (GetFileInformationByHandle(fh, &fdata)) {
 224                buf->st_ino = 0;
 225                buf->st_gid = 0;
 226                buf->st_uid = 0;
 227                buf->st_nlink = 1;
 228                buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 229                buf->st_size = fdata.nFileSizeLow |
 230                        (((off_t)fdata.nFileSizeHigh)<<32);
 231                buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 232                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 233                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 234                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 235                return 0;
 236        }
 237        errno = EBADF;
 238        return -1;
 239}
 240
 241static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 242{
 243        long long winTime = t * 10000000LL + 116444736000000000LL;
 244        ft->dwLowDateTime = winTime;
 245        ft->dwHighDateTime = winTime >> 32;
 246}
 247
 248int mingw_utime (const char *file_name, const struct utimbuf *times)
 249{
 250        FILETIME mft, aft;
 251        int fh, rc;
 252
 253        /* must have write permission */
 254        if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
 255                return -1;
 256
 257        time_t_to_filetime(times->modtime, &mft);
 258        time_t_to_filetime(times->actime, &aft);
 259        if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 260                errno = EINVAL;
 261                rc = -1;
 262        } else
 263                rc = 0;
 264        close(fh);
 265        return rc;
 266}
 267
 268unsigned int sleep (unsigned int seconds)
 269{
 270        Sleep(seconds*1000);
 271        return 0;
 272}
 273
 274int mkstemp(char *template)
 275{
 276        char *filename = mktemp(template);
 277        if (filename == NULL)
 278                return -1;
 279        return open(filename, O_RDWR | O_CREAT, 0600);
 280}
 281
 282int gettimeofday(struct timeval *tv, void *tz)
 283{
 284        SYSTEMTIME st;
 285        struct tm tm;
 286        GetSystemTime(&st);
 287        tm.tm_year = st.wYear-1900;
 288        tm.tm_mon = st.wMonth-1;
 289        tm.tm_mday = st.wDay;
 290        tm.tm_hour = st.wHour;
 291        tm.tm_min = st.wMinute;
 292        tm.tm_sec = st.wSecond;
 293        tv->tv_sec = tm_to_time_t(&tm);
 294        if (tv->tv_sec < 0)
 295                return -1;
 296        tv->tv_usec = st.wMilliseconds*1000;
 297        return 0;
 298}
 299
 300int pipe(int filedes[2])
 301{
 302        HANDLE h[2];
 303
 304        /* this creates non-inheritable handles */
 305        if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
 306                errno = err_win_to_posix(GetLastError());
 307                return -1;
 308        }
 309        filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
 310        if (filedes[0] < 0) {
 311                CloseHandle(h[0]);
 312                CloseHandle(h[1]);
 313                return -1;
 314        }
 315        filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
 316        if (filedes[0] < 0) {
 317                close(filedes[0]);
 318                CloseHandle(h[1]);
 319                return -1;
 320        }
 321        return 0;
 322}
 323
 324int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
 325{
 326        int i, pending;
 327
 328        if (timeout >= 0) {
 329                if (nfds == 0) {
 330                        Sleep(timeout);
 331                        return 0;
 332                }
 333                return errno = EINVAL, error("poll timeout not supported");
 334        }
 335
 336        /* When there is only one fd to wait for, then we pretend that
 337         * input is available and let the actual wait happen when the
 338         * caller invokes read().
 339         */
 340        if (nfds == 1) {
 341                if (!(ufds[0].events & POLLIN))
 342                        return errno = EINVAL, error("POLLIN not set");
 343                ufds[0].revents = POLLIN;
 344                return 0;
 345        }
 346
 347repeat:
 348        pending = 0;
 349        for (i = 0; i < nfds; i++) {
 350                DWORD avail = 0;
 351                HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
 352                if (h == INVALID_HANDLE_VALUE)
 353                        return -1;      /* errno was set */
 354
 355                if (!(ufds[i].events & POLLIN))
 356                        return errno = EINVAL, error("POLLIN not set");
 357
 358                /* this emulation works only for pipes */
 359                if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
 360                        int err = GetLastError();
 361                        if (err == ERROR_BROKEN_PIPE) {
 362                                ufds[i].revents = POLLHUP;
 363                                pending++;
 364                        } else {
 365                                errno = EINVAL;
 366                                return error("PeekNamedPipe failed,"
 367                                        " GetLastError: %u", err);
 368                        }
 369                } else if (avail) {
 370                        ufds[i].revents = POLLIN;
 371                        pending++;
 372                } else
 373                        ufds[i].revents = 0;
 374        }
 375        if (!pending) {
 376                /* The only times that we spin here is when the process
 377                 * that is connected through the pipes is waiting for
 378                 * its own input data to become available. But since
 379                 * the process (pack-objects) is itself CPU intensive,
 380                 * it will happily pick up the time slice that we are
 381                 * relinquishing here.
 382                 */
 383                Sleep(0);
 384                goto repeat;
 385        }
 386        return 0;
 387}
 388
 389struct tm *gmtime_r(const time_t *timep, struct tm *result)
 390{
 391        /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 392        memcpy(result, gmtime(timep), sizeof(struct tm));
 393        return result;
 394}
 395
 396struct tm *localtime_r(const time_t *timep, struct tm *result)
 397{
 398        /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 399        memcpy(result, localtime(timep), sizeof(struct tm));
 400        return result;
 401}
 402
 403#undef getcwd
 404char *mingw_getcwd(char *pointer, int len)
 405{
 406        int i;
 407        char *ret = getcwd(pointer, len);
 408        if (!ret)
 409                return ret;
 410        for (i = 0; pointer[i]; i++)
 411                if (pointer[i] == '\\')
 412                        pointer[i] = '/';
 413        return ret;
 414}
 415
 416#undef getenv
 417char *mingw_getenv(const char *name)
 418{
 419        char *result = getenv(name);
 420        if (!result && !strcmp(name, "TMPDIR")) {
 421                /* on Windows it is TMP and TEMP */
 422                result = getenv("TMP");
 423                if (!result)
 424                        result = getenv("TEMP");
 425        }
 426        return result;
 427}
 428
 429/*
 430 * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 431 * (Parsing C++ Command-Line Arguments)
 432 */
 433static const char *quote_arg(const char *arg)
 434{
 435        /* count chars to quote */
 436        int len = 0, n = 0;
 437        int force_quotes = 0;
 438        char *q, *d;
 439        const char *p = arg;
 440        if (!*p) force_quotes = 1;
 441        while (*p) {
 442                if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 443                        force_quotes = 1;
 444                else if (*p == '"')
 445                        n++;
 446                else if (*p == '\\') {
 447                        int count = 0;
 448                        while (*p == '\\') {
 449                                count++;
 450                                p++;
 451                                len++;
 452                        }
 453                        if (*p == '"')
 454                                n += count*2 + 1;
 455                        continue;
 456                }
 457                len++;
 458                p++;
 459        }
 460        if (!force_quotes && n == 0)
 461                return arg;
 462
 463        /* insert \ where necessary */
 464        d = q = xmalloc(len+n+3);
 465        *d++ = '"';
 466        while (*arg) {
 467                if (*arg == '"')
 468                        *d++ = '\\';
 469                else if (*arg == '\\') {
 470                        int count = 0;
 471                        while (*arg == '\\') {
 472                                count++;
 473                                *d++ = *arg++;
 474                        }
 475                        if (*arg == '"') {
 476                                while (count-- > 0)
 477                                        *d++ = '\\';
 478                                *d++ = '\\';
 479                        }
 480                }
 481                *d++ = *arg++;
 482        }
 483        *d++ = '"';
 484        *d++ = 0;
 485        return q;
 486}
 487
 488static const char *parse_interpreter(const char *cmd)
 489{
 490        static char buf[100];
 491        char *p, *opt;
 492        int n, fd;
 493
 494        /* don't even try a .exe */
 495        n = strlen(cmd);
 496        if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 497                return NULL;
 498
 499        fd = open(cmd, O_RDONLY);
 500        if (fd < 0)
 501                return NULL;
 502        n = read(fd, buf, sizeof(buf)-1);
 503        close(fd);
 504        if (n < 4)      /* at least '#!/x' and not error */
 505                return NULL;
 506
 507        if (buf[0] != '#' || buf[1] != '!')
 508                return NULL;
 509        buf[n] = '\0';
 510        p = buf + strcspn(buf, "\r\n");
 511        if (!*p)
 512                return NULL;
 513
 514        *p = '\0';
 515        if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 516                return NULL;
 517        /* strip options */
 518        if ((opt = strchr(p+1, ' ')))
 519                *opt = '\0';
 520        return p+1;
 521}
 522
 523/*
 524 * Splits the PATH into parts.
 525 */
 526static char **get_path_split(void)
 527{
 528        char *p, **path, *envpath = getenv("PATH");
 529        int i, n = 0;
 530
 531        if (!envpath || !*envpath)
 532                return NULL;
 533
 534        envpath = xstrdup(envpath);
 535        p = envpath;
 536        while (p) {
 537                char *dir = p;
 538                p = strchr(p, ';');
 539                if (p) *p++ = '\0';
 540                if (*dir) {     /* not earlier, catches series of ; */
 541                        ++n;
 542                }
 543        }
 544        if (!n)
 545                return NULL;
 546
 547        path = xmalloc((n+1)*sizeof(char *));
 548        p = envpath;
 549        i = 0;
 550        do {
 551                if (*p)
 552                        path[i++] = xstrdup(p);
 553                p = p+strlen(p)+1;
 554        } while (i < n);
 555        path[i] = NULL;
 556
 557        free(envpath);
 558
 559        return path;
 560}
 561
 562static void free_path_split(char **path)
 563{
 564        char **p = path;
 565
 566        if (!path)
 567                return;
 568
 569        while (*p)
 570                free(*p++);
 571        free(path);
 572}
 573
 574/*
 575 * exe_only means that we only want to detect .exe files, but not scripts
 576 * (which do not have an extension)
 577 */
 578static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 579{
 580        char path[MAX_PATH];
 581        snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 582
 583        if (!isexe && access(path, F_OK) == 0)
 584                return xstrdup(path);
 585        path[strlen(path)-4] = '\0';
 586        if ((!exe_only || isexe) && access(path, F_OK) == 0)
 587                if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 588                        return xstrdup(path);
 589        return NULL;
 590}
 591
 592/*
 593 * Determines the absolute path of cmd using the the split path in path.
 594 * If cmd contains a slash or backslash, no lookup is performed.
 595 */
 596static char *path_lookup(const char *cmd, char **path, int exe_only)
 597{
 598        char *prog = NULL;
 599        int len = strlen(cmd);
 600        int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 601
 602        if (strchr(cmd, '/') || strchr(cmd, '\\'))
 603                prog = xstrdup(cmd);
 604
 605        while (!prog && *path)
 606                prog = lookup_prog(*path++, cmd, isexe, exe_only);
 607
 608        return prog;
 609}
 610
 611static int env_compare(const void *a, const void *b)
 612{
 613        char *const *ea = a;
 614        char *const *eb = b;
 615        return strcasecmp(*ea, *eb);
 616}
 617
 618static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
 619                              int prepend_cmd, int fhin, int fhout, int fherr)
 620{
 621        STARTUPINFO si;
 622        PROCESS_INFORMATION pi;
 623        struct strbuf envblk, args;
 624        unsigned flags;
 625        BOOL ret;
 626
 627        /* Determine whether or not we are associated to a console */
 628        HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 629                        FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 630                        FILE_ATTRIBUTE_NORMAL, NULL);
 631        if (cons == INVALID_HANDLE_VALUE) {
 632                /* There is no console associated with this process.
 633                 * Since the child is a console process, Windows
 634                 * would normally create a console window. But
 635                 * since we'll be redirecting std streams, we do
 636                 * not need the console.
 637                 * It is necessary to use DETACHED_PROCESS
 638                 * instead of CREATE_NO_WINDOW to make ssh
 639                 * recognize that it has no console.
 640                 */
 641                flags = DETACHED_PROCESS;
 642        } else {
 643                /* There is already a console. If we specified
 644                 * DETACHED_PROCESS here, too, Windows would
 645                 * disassociate the child from the console.
 646                 * The same is true for CREATE_NO_WINDOW.
 647                 * Go figure!
 648                 */
 649                flags = 0;
 650                CloseHandle(cons);
 651        }
 652        memset(&si, 0, sizeof(si));
 653        si.cb = sizeof(si);
 654        si.dwFlags = STARTF_USESTDHANDLES;
 655        si.hStdInput = (HANDLE) _get_osfhandle(fhin);
 656        si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
 657        si.hStdError = (HANDLE) _get_osfhandle(fherr);
 658
 659        /* concatenate argv, quoting args as we go */
 660        strbuf_init(&args, 0);
 661        if (prepend_cmd) {
 662                char *quoted = (char *)quote_arg(cmd);
 663                strbuf_addstr(&args, quoted);
 664                if (quoted != cmd)
 665                        free(quoted);
 666        }
 667        for (; *argv; argv++) {
 668                char *quoted = (char *)quote_arg(*argv);
 669                if (*args.buf)
 670                        strbuf_addch(&args, ' ');
 671                strbuf_addstr(&args, quoted);
 672                if (quoted != *argv)
 673                        free(quoted);
 674        }
 675
 676        if (env) {
 677                int count = 0;
 678                char **e, **sorted_env;
 679
 680                for (e = env; *e; e++)
 681                        count++;
 682
 683                /* environment must be sorted */
 684                sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 685                memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 686                qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 687
 688                strbuf_init(&envblk, 0);
 689                for (e = sorted_env; *e; e++) {
 690                        strbuf_addstr(&envblk, *e);
 691                        strbuf_addch(&envblk, '\0');
 692                }
 693                free(sorted_env);
 694        }
 695
 696        memset(&pi, 0, sizeof(pi));
 697        ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 698                env ? envblk.buf : NULL, NULL, &si, &pi);
 699
 700        if (env)
 701                strbuf_release(&envblk);
 702        strbuf_release(&args);
 703
 704        if (!ret) {
 705                errno = ENOENT;
 706                return -1;
 707        }
 708        CloseHandle(pi.hThread);
 709        return (pid_t)pi.hProcess;
 710}
 711
 712static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 713                           int prepend_cmd)
 714{
 715        return mingw_spawnve_fd(cmd, argv, env, prepend_cmd, 0, 1, 2);
 716}
 717
 718pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
 719                     int fhin, int fhout, int fherr)
 720{
 721        pid_t pid;
 722        char **path = get_path_split();
 723        char *prog = path_lookup(cmd, path, 0);
 724
 725        if (!prog) {
 726                errno = ENOENT;
 727                pid = -1;
 728        }
 729        else {
 730                const char *interpr = parse_interpreter(prog);
 731
 732                if (interpr) {
 733                        const char *argv0 = argv[0];
 734                        char *iprog = path_lookup(interpr, path, 1);
 735                        argv[0] = prog;
 736                        if (!iprog) {
 737                                errno = ENOENT;
 738                                pid = -1;
 739                        }
 740                        else {
 741                                pid = mingw_spawnve_fd(iprog, argv, env, 1,
 742                                                       fhin, fhout, fherr);
 743                                free(iprog);
 744                        }
 745                        argv[0] = argv0;
 746                }
 747                else
 748                        pid = mingw_spawnve_fd(prog, argv, env, 0,
 749                                               fhin, fhout, fherr);
 750                free(prog);
 751        }
 752        free_path_split(path);
 753        return pid;
 754}
 755
 756static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 757{
 758        const char *interpr = parse_interpreter(cmd);
 759        char **path;
 760        char *prog;
 761        int pid = 0;
 762
 763        if (!interpr)
 764                return 0;
 765        path = get_path_split();
 766        prog = path_lookup(interpr, path, 1);
 767        if (prog) {
 768                int argc = 0;
 769                const char **argv2;
 770                while (argv[argc]) argc++;
 771                argv2 = xmalloc(sizeof(*argv) * (argc+1));
 772                argv2[0] = (char *)cmd; /* full path to the script file */
 773                memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 774                pid = mingw_spawnve(prog, argv2, env, 1);
 775                if (pid >= 0) {
 776                        int status;
 777                        if (waitpid(pid, &status, 0) < 0)
 778                                status = 255;
 779                        exit(status);
 780                }
 781                pid = 1;        /* indicate that we tried but failed */
 782                free(prog);
 783                free(argv2);
 784        }
 785        free_path_split(path);
 786        return pid;
 787}
 788
 789static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 790{
 791        /* check if git_command is a shell script */
 792        if (!try_shell_exec(cmd, argv, (char **)env)) {
 793                int pid, status;
 794
 795                pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 796                if (pid < 0)
 797                        return;
 798                if (waitpid(pid, &status, 0) < 0)
 799                        status = 255;
 800                exit(status);
 801        }
 802}
 803
 804void mingw_execvp(const char *cmd, char *const *argv)
 805{
 806        char **path = get_path_split();
 807        char *prog = path_lookup(cmd, path, 0);
 808
 809        if (prog) {
 810                mingw_execve(prog, argv, environ);
 811                free(prog);
 812        } else
 813                errno = ENOENT;
 814
 815        free_path_split(path);
 816}
 817
 818static char **copy_environ(void)
 819{
 820        char **env;
 821        int i = 0;
 822        while (environ[i])
 823                i++;
 824        env = xmalloc((i+1)*sizeof(*env));
 825        for (i = 0; environ[i]; i++)
 826                env[i] = xstrdup(environ[i]);
 827        env[i] = NULL;
 828        return env;
 829}
 830
 831void free_environ(char **env)
 832{
 833        int i;
 834        for (i = 0; env[i]; i++)
 835                free(env[i]);
 836        free(env);
 837}
 838
 839static int lookup_env(char **env, const char *name, size_t nmln)
 840{
 841        int i;
 842
 843        for (i = 0; env[i]; i++) {
 844                if (0 == strncmp(env[i], name, nmln)
 845                    && '=' == env[i][nmln])
 846                        /* matches */
 847                        return i;
 848        }
 849        return -1;
 850}
 851
 852/*
 853 * If name contains '=', then sets the variable, otherwise it unsets it
 854 */
 855static char **env_setenv(char **env, const char *name)
 856{
 857        char *eq = strchrnul(name, '=');
 858        int i = lookup_env(env, name, eq-name);
 859
 860        if (i < 0) {
 861                if (*eq) {
 862                        for (i = 0; env[i]; i++)
 863                                ;
 864                        env = xrealloc(env, (i+2)*sizeof(*env));
 865                        env[i] = xstrdup(name);
 866                        env[i+1] = NULL;
 867                }
 868        }
 869        else {
 870                free(env[i]);
 871                if (*eq)
 872                        env[i] = xstrdup(name);
 873                else
 874                        for (; env[i]; i++)
 875                                env[i] = env[i+1];
 876        }
 877        return env;
 878}
 879
 880/*
 881 * Copies global environ and adjusts variables as specified by vars.
 882 */
 883char **make_augmented_environ(const char *const *vars)
 884{
 885        char **env = copy_environ();
 886
 887        while (*vars)
 888                env = env_setenv(env, *vars++);
 889        return env;
 890}
 891
 892/*
 893 * Note, this isn't a complete replacement for getaddrinfo. It assumes
 894 * that service contains a numerical port, or that it it is null. It
 895 * does a simple search using gethostbyname, and returns one IPv4 host
 896 * if one was found.
 897 */
 898static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
 899                                   const struct addrinfo *hints,
 900                                   struct addrinfo **res)
 901{
 902        struct hostent *h = gethostbyname(node);
 903        struct addrinfo *ai;
 904        struct sockaddr_in *sin;
 905
 906        if (!h)
 907                return WSAGetLastError();
 908
 909        ai = xmalloc(sizeof(struct addrinfo));
 910        *res = ai;
 911        ai->ai_flags = 0;
 912        ai->ai_family = AF_INET;
 913        ai->ai_socktype = hints->ai_socktype;
 914        switch (hints->ai_socktype) {
 915        case SOCK_STREAM:
 916                ai->ai_protocol = IPPROTO_TCP;
 917                break;
 918        case SOCK_DGRAM:
 919                ai->ai_protocol = IPPROTO_UDP;
 920                break;
 921        default:
 922                ai->ai_protocol = 0;
 923                break;
 924        }
 925        ai->ai_addrlen = sizeof(struct sockaddr_in);
 926        ai->ai_canonname = strdup(h->h_name);
 927
 928        sin = xmalloc(ai->ai_addrlen);
 929        memset(sin, 0, ai->ai_addrlen);
 930        sin->sin_family = AF_INET;
 931        if (service)
 932                sin->sin_port = htons(atoi(service));
 933        sin->sin_addr = *(struct in_addr *)h->h_addr;
 934        ai->ai_addr = (struct sockaddr *)sin;
 935        ai->ai_next = 0;
 936        return 0;
 937}
 938
 939static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
 940{
 941        free(res->ai_canonname);
 942        free(res->ai_addr);
 943        free(res);
 944}
 945
 946static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
 947                                   char *host, DWORD hostlen,
 948                                   char *serv, DWORD servlen, int flags)
 949{
 950        const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
 951        if (sa->sa_family != AF_INET)
 952                return EAI_FAMILY;
 953        if (!host && !serv)
 954                return EAI_NONAME;
 955
 956        if (host && hostlen > 0) {
 957                struct hostent *ent = NULL;
 958                if (!(flags & NI_NUMERICHOST))
 959                        ent = gethostbyaddr((const char *)&sin->sin_addr,
 960                                            sizeof(sin->sin_addr), AF_INET);
 961
 962                if (ent)
 963                        snprintf(host, hostlen, "%s", ent->h_name);
 964                else if (flags & NI_NAMEREQD)
 965                        return EAI_NONAME;
 966                else
 967                        snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
 968        }
 969
 970        if (serv && servlen > 0) {
 971                struct servent *ent = NULL;
 972                if (!(flags & NI_NUMERICSERV))
 973                        ent = getservbyport(sin->sin_port,
 974                                            flags & NI_DGRAM ? "udp" : "tcp");
 975
 976                if (ent)
 977                        snprintf(serv, servlen, "%s", ent->s_name);
 978                else
 979                        snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
 980        }
 981
 982        return 0;
 983}
 984
 985static HMODULE ipv6_dll = NULL;
 986static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
 987static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
 988                                      const struct addrinfo *hints,
 989                                      struct addrinfo **res);
 990static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
 991                                      char *host, DWORD hostlen,
 992                                      char *serv, DWORD servlen, int flags);
 993/*
 994 * gai_strerror is an inline function in the ws2tcpip.h header, so we
 995 * don't need to try to load that one dynamically.
 996 */
 997
 998static void socket_cleanup(void)
 999{
1000        WSACleanup();
1001        if (ipv6_dll)
1002                FreeLibrary(ipv6_dll);
1003        ipv6_dll = NULL;
1004        ipv6_freeaddrinfo = freeaddrinfo_stub;
1005        ipv6_getaddrinfo = getaddrinfo_stub;
1006        ipv6_getnameinfo = getnameinfo_stub;
1007}
1008
1009static void ensure_socket_initialization(void)
1010{
1011        WSADATA wsa;
1012        static int initialized = 0;
1013        const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
1014        const char **name;
1015
1016        if (initialized)
1017                return;
1018
1019        if (WSAStartup(MAKEWORD(2,2), &wsa))
1020                die("unable to initialize winsock subsystem, error %d",
1021                        WSAGetLastError());
1022
1023        for (name = libraries; *name; name++) {
1024                ipv6_dll = LoadLibrary(*name);
1025                if (!ipv6_dll)
1026                        continue;
1027
1028                ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
1029                        GetProcAddress(ipv6_dll, "freeaddrinfo");
1030                ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
1031                                                   const struct addrinfo *,
1032                                                   struct addrinfo **))
1033                        GetProcAddress(ipv6_dll, "getaddrinfo");
1034                ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
1035                                                   socklen_t, char *, DWORD,
1036                                                   char *, DWORD, int))
1037                        GetProcAddress(ipv6_dll, "getnameinfo");
1038                if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1039                        FreeLibrary(ipv6_dll);
1040                        ipv6_dll = NULL;
1041                } else
1042                        break;
1043        }
1044        if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1045                ipv6_freeaddrinfo = freeaddrinfo_stub;
1046                ipv6_getaddrinfo = getaddrinfo_stub;
1047                ipv6_getnameinfo = getnameinfo_stub;
1048        }
1049
1050        atexit(socket_cleanup);
1051        initialized = 1;
1052}
1053
1054#undef gethostbyname
1055struct hostent *mingw_gethostbyname(const char *host)
1056{
1057        ensure_socket_initialization();
1058        return gethostbyname(host);
1059}
1060
1061void mingw_freeaddrinfo(struct addrinfo *res)
1062{
1063        ipv6_freeaddrinfo(res);
1064}
1065
1066int mingw_getaddrinfo(const char *node, const char *service,
1067                      const struct addrinfo *hints, struct addrinfo **res)
1068{
1069        ensure_socket_initialization();
1070        return ipv6_getaddrinfo(node, service, hints, res);
1071}
1072
1073int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
1074                      char *host, DWORD hostlen, char *serv, DWORD servlen,
1075                      int flags)
1076{
1077        ensure_socket_initialization();
1078        return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
1079}
1080
1081int mingw_socket(int domain, int type, int protocol)
1082{
1083        int sockfd;
1084        SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
1085        if (s == INVALID_SOCKET) {
1086                /*
1087                 * WSAGetLastError() values are regular BSD error codes
1088                 * biased by WSABASEERR.
1089                 * However, strerror() does not know about networking
1090                 * specific errors, which are values beginning at 38 or so.
1091                 * Therefore, we choose to leave the biased error code
1092                 * in errno so that _if_ someone looks up the code somewhere,
1093                 * then it is at least the number that are usually listed.
1094                 */
1095                errno = WSAGetLastError();
1096                return -1;
1097        }
1098        /* convert into a file descriptor */
1099        if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
1100                closesocket(s);
1101                return error("unable to make a socket file descriptor: %s",
1102                        strerror(errno));
1103        }
1104        return sockfd;
1105}
1106
1107#undef connect
1108int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1109{
1110        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1111        return connect(s, sa, sz);
1112}
1113
1114#undef rename
1115int mingw_rename(const char *pold, const char *pnew)
1116{
1117        DWORD attrs, gle;
1118        int tries = 0;
1119        static const int delay[] = { 0, 1, 10, 20, 40 };
1120
1121        /*
1122         * Try native rename() first to get errno right.
1123         * It is based on MoveFile(), which cannot overwrite existing files.
1124         */
1125        if (!rename(pold, pnew))
1126                return 0;
1127        if (errno != EEXIST)
1128                return -1;
1129repeat:
1130        if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1131                return 0;
1132        /* TODO: translate more errors */
1133        gle = GetLastError();
1134        if (gle == ERROR_ACCESS_DENIED &&
1135            (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1136                if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1137                        errno = EISDIR;
1138                        return -1;
1139                }
1140                if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1141                    SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1142                        if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1143                                return 0;
1144                        gle = GetLastError();
1145                        /* revert file attributes on failure */
1146                        SetFileAttributes(pnew, attrs);
1147                }
1148        }
1149        if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1150                /*
1151                 * We assume that some other process had the source or
1152                 * destination file open at the wrong moment and retry.
1153                 * In order to give the other process a higher chance to
1154                 * complete its operation, we give up our time slice now.
1155                 * If we have to retry again, we do sleep a bit.
1156                 */
1157                Sleep(delay[tries]);
1158                tries++;
1159                goto repeat;
1160        }
1161        errno = EACCES;
1162        return -1;
1163}
1164
1165/*
1166 * Note that this doesn't return the actual pagesize, but
1167 * the allocation granularity. If future Windows specific git code
1168 * needs the real getpagesize function, we need to find another solution.
1169 */
1170int mingw_getpagesize(void)
1171{
1172        SYSTEM_INFO si;
1173        GetSystemInfo(&si);
1174        return si.dwAllocationGranularity;
1175}
1176
1177struct passwd *getpwuid(int uid)
1178{
1179        static char user_name[100];
1180        static struct passwd p;
1181
1182        DWORD len = sizeof(user_name);
1183        if (!GetUserName(user_name, &len))
1184                return NULL;
1185        p.pw_name = user_name;
1186        p.pw_gecos = "unknown";
1187        p.pw_dir = NULL;
1188        return &p;
1189}
1190
1191static HANDLE timer_event;
1192static HANDLE timer_thread;
1193static int timer_interval;
1194static int one_shot;
1195static sig_handler_t timer_fn = SIG_DFL;
1196
1197/* The timer works like this:
1198 * The thread, ticktack(), is a trivial routine that most of the time
1199 * only waits to receive the signal to terminate. The main thread tells
1200 * the thread to terminate by setting the timer_event to the signalled
1201 * state.
1202 * But ticktack() interrupts the wait state after the timer's interval
1203 * length to call the signal handler.
1204 */
1205
1206static unsigned __stdcall ticktack(void *dummy)
1207{
1208        while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1209                if (timer_fn == SIG_DFL)
1210                        die("Alarm");
1211                if (timer_fn != SIG_IGN)
1212                        timer_fn(SIGALRM);
1213                if (one_shot)
1214                        break;
1215        }
1216        return 0;
1217}
1218
1219static int start_timer_thread(void)
1220{
1221        timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1222        if (timer_event) {
1223                timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1224                if (!timer_thread )
1225                        return errno = ENOMEM,
1226                                error("cannot start timer thread");
1227        } else
1228                return errno = ENOMEM,
1229                        error("cannot allocate resources for timer");
1230        return 0;
1231}
1232
1233static void stop_timer_thread(void)
1234{
1235        if (timer_event)
1236                SetEvent(timer_event);  /* tell thread to terminate */
1237        if (timer_thread) {
1238                int rc = WaitForSingleObject(timer_thread, 1000);
1239                if (rc == WAIT_TIMEOUT)
1240                        error("timer thread did not terminate timely");
1241                else if (rc != WAIT_OBJECT_0)
1242                        error("waiting for timer thread failed: %lu",
1243                              GetLastError());
1244                CloseHandle(timer_thread);
1245        }
1246        if (timer_event)
1247                CloseHandle(timer_event);
1248        timer_event = NULL;
1249        timer_thread = NULL;
1250}
1251
1252static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1253{
1254        return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1255}
1256
1257int setitimer(int type, struct itimerval *in, struct itimerval *out)
1258{
1259        static const struct timeval zero;
1260        static int atexit_done;
1261
1262        if (out != NULL)
1263                return errno = EINVAL,
1264                        error("setitimer param 3 != NULL not implemented");
1265        if (!is_timeval_eq(&in->it_interval, &zero) &&
1266            !is_timeval_eq(&in->it_interval, &in->it_value))
1267                return errno = EINVAL,
1268                        error("setitimer: it_interval must be zero or eq it_value");
1269
1270        if (timer_thread)
1271                stop_timer_thread();
1272
1273        if (is_timeval_eq(&in->it_value, &zero) &&
1274            is_timeval_eq(&in->it_interval, &zero))
1275                return 0;
1276
1277        timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1278        one_shot = is_timeval_eq(&in->it_interval, &zero);
1279        if (!atexit_done) {
1280                atexit(stop_timer_thread);
1281                atexit_done = 1;
1282        }
1283        return start_timer_thread();
1284}
1285
1286int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1287{
1288        if (sig != SIGALRM)
1289                return errno = EINVAL,
1290                        error("sigaction only implemented for SIGALRM");
1291        if (out != NULL)
1292                return errno = EINVAL,
1293                        error("sigaction: param 3 != NULL not implemented");
1294
1295        timer_fn = in->sa_handler;
1296        return 0;
1297}
1298
1299#undef signal
1300sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1301{
1302        sig_handler_t old = timer_fn;
1303        if (sig != SIGALRM)
1304                return signal(sig, handler);
1305        timer_fn = handler;
1306        return old;
1307}
1308
1309static const char *make_backslash_path(const char *path)
1310{
1311        static char buf[PATH_MAX + 1];
1312        char *c;
1313
1314        if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1315                die("Too long path: %.*s", 60, path);
1316
1317        for (c = buf; *c; c++) {
1318                if (*c == '/')
1319                        *c = '\\';
1320        }
1321        return buf;
1322}
1323
1324void mingw_open_html(const char *unixpath)
1325{
1326        const char *htmlpath = make_backslash_path(unixpath);
1327        typedef HINSTANCE (WINAPI *T)(HWND, const char *,
1328                        const char *, const char *, const char *, INT);
1329        T ShellExecute;
1330        HMODULE shell32;
1331
1332        shell32 = LoadLibrary("shell32.dll");
1333        if (!shell32)
1334                die("cannot load shell32.dll");
1335        ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
1336        if (!ShellExecute)
1337                die("cannot run browser");
1338
1339        printf("Launching default browser to display HTML ...\n");
1340        ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
1341
1342        FreeLibrary(shell32);
1343}
1344
1345int link(const char *oldpath, const char *newpath)
1346{
1347        typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1348        static T create_hard_link = NULL;
1349        if (!create_hard_link) {
1350                create_hard_link = (T) GetProcAddress(
1351                        GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1352                if (!create_hard_link)
1353                        create_hard_link = (T)-1;
1354        }
1355        if (create_hard_link == (T)-1) {
1356                errno = ENOSYS;
1357                return -1;
1358        }
1359        if (!create_hard_link(newpath, oldpath, NULL)) {
1360                errno = err_win_to_posix(GetLastError());
1361                return -1;
1362        }
1363        return 0;
1364}
1365
1366char *getpass(const char *prompt)
1367{
1368        struct strbuf buf = STRBUF_INIT;
1369
1370        fputs(prompt, stderr);
1371        for (;;) {
1372                char c = _getch();
1373                if (c == '\r' || c == '\n')
1374                        break;
1375                strbuf_addch(&buf, c);
1376        }
1377        fputs("\n", stderr);
1378        return strbuf_detach(&buf, NULL);
1379}
1380
1381#ifndef NO_MINGW_REPLACE_READDIR
1382/* MinGW readdir implementation to avoid extra lstats for Git */
1383struct mingw_DIR
1384{
1385        struct _finddata_t      dd_dta;         /* disk transfer area for this dir */
1386        struct mingw_dirent     dd_dir;         /* Our own implementation, including d_type */
1387        long                    dd_handle;      /* _findnext handle */
1388        int                     dd_stat;        /* 0 = next entry to read is first entry, -1 = off the end, positive = 0 based index of next entry */
1389        char                    dd_name[1];     /* given path for dir with search pattern (struct is extended) */
1390};
1391
1392struct dirent *mingw_readdir(DIR *dir)
1393{
1394        WIN32_FIND_DATAA buf;
1395        HANDLE handle;
1396        struct mingw_DIR *mdir = (struct mingw_DIR*)dir;
1397
1398        if (!dir->dd_handle) {
1399                errno = EBADF; /* No set_errno for mingw */
1400                return NULL;
1401        }
1402
1403        if (dir->dd_handle == (long)INVALID_HANDLE_VALUE && dir->dd_stat == 0)
1404        {
1405                DWORD lasterr;
1406                handle = FindFirstFileA(dir->dd_name, &buf);
1407                lasterr = GetLastError();
1408                dir->dd_handle = (long)handle;
1409                if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES)) {
1410                        errno = err_win_to_posix(lasterr);
1411                        return NULL;
1412                }
1413        } else if (dir->dd_handle == (long)INVALID_HANDLE_VALUE) {
1414                return NULL;
1415        } else if (!FindNextFileA((HANDLE)dir->dd_handle, &buf)) {
1416                DWORD lasterr = GetLastError();
1417                FindClose((HANDLE)dir->dd_handle);
1418                dir->dd_handle = (long)INVALID_HANDLE_VALUE;
1419                /* POSIX says you shouldn't set errno when readdir can't
1420                   find any more files; so, if another error we leave it set. */
1421                if (lasterr != ERROR_NO_MORE_FILES)
1422                        errno = err_win_to_posix(lasterr);
1423                return NULL;
1424        }
1425
1426        /* We get here if `buf' contains valid data.  */
1427        strcpy(dir->dd_dir.d_name, buf.cFileName);
1428        ++dir->dd_stat;
1429
1430        /* Set file type, based on WIN32_FIND_DATA */
1431        mdir->dd_dir.d_type = 0;
1432        if (buf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
1433                mdir->dd_dir.d_type |= DT_DIR;
1434        else
1435                mdir->dd_dir.d_type |= DT_REG;
1436
1437        return (struct dirent*)&dir->dd_dir;
1438}
1439#endif // !NO_MINGW_REPLACE_READDIR