compat / mingw.con commit contrib: add credential helper for OS X Keychain (34961d3)
   1#include "../git-compat-util.h"
   2#include "win32.h"
   3#include <conio.h>
   4#include "../strbuf.h"
   5#include "../run-command.h"
   6
   7static const int delay[] = { 0, 1, 10, 20, 40 };
   8
   9int err_win_to_posix(DWORD winerr)
  10{
  11        int error = ENOSYS;
  12        switch(winerr) {
  13        case ERROR_ACCESS_DENIED: error = EACCES; break;
  14        case ERROR_ACCOUNT_DISABLED: error = EACCES; break;
  15        case ERROR_ACCOUNT_RESTRICTION: error = EACCES; break;
  16        case ERROR_ALREADY_ASSIGNED: error = EBUSY; break;
  17        case ERROR_ALREADY_EXISTS: error = EEXIST; break;
  18        case ERROR_ARITHMETIC_OVERFLOW: error = ERANGE; break;
  19        case ERROR_BAD_COMMAND: error = EIO; break;
  20        case ERROR_BAD_DEVICE: error = ENODEV; break;
  21        case ERROR_BAD_DRIVER_LEVEL: error = ENXIO; break;
  22        case ERROR_BAD_EXE_FORMAT: error = ENOEXEC; break;
  23        case ERROR_BAD_FORMAT: error = ENOEXEC; break;
  24        case ERROR_BAD_LENGTH: error = EINVAL; break;
  25        case ERROR_BAD_PATHNAME: error = ENOENT; break;
  26        case ERROR_BAD_PIPE: error = EPIPE; break;
  27        case ERROR_BAD_UNIT: error = ENODEV; break;
  28        case ERROR_BAD_USERNAME: error = EINVAL; break;
  29        case ERROR_BROKEN_PIPE: error = EPIPE; break;
  30        case ERROR_BUFFER_OVERFLOW: error = ENAMETOOLONG; break;
  31        case ERROR_BUSY: error = EBUSY; break;
  32        case ERROR_BUSY_DRIVE: error = EBUSY; break;
  33        case ERROR_CALL_NOT_IMPLEMENTED: error = ENOSYS; break;
  34        case ERROR_CANNOT_MAKE: error = EACCES; break;
  35        case ERROR_CANTOPEN: error = EIO; break;
  36        case ERROR_CANTREAD: error = EIO; break;
  37        case ERROR_CANTWRITE: error = EIO; break;
  38        case ERROR_CRC: error = EIO; break;
  39        case ERROR_CURRENT_DIRECTORY: error = EACCES; break;
  40        case ERROR_DEVICE_IN_USE: error = EBUSY; break;
  41        case ERROR_DEV_NOT_EXIST: error = ENODEV; break;
  42        case ERROR_DIRECTORY: error = EINVAL; break;
  43        case ERROR_DIR_NOT_EMPTY: error = ENOTEMPTY; break;
  44        case ERROR_DISK_CHANGE: error = EIO; break;
  45        case ERROR_DISK_FULL: error = ENOSPC; break;
  46        case ERROR_DRIVE_LOCKED: error = EBUSY; break;
  47        case ERROR_ENVVAR_NOT_FOUND: error = EINVAL; break;
  48        case ERROR_EXE_MARKED_INVALID: error = ENOEXEC; break;
  49        case ERROR_FILENAME_EXCED_RANGE: error = ENAMETOOLONG; break;
  50        case ERROR_FILE_EXISTS: error = EEXIST; break;
  51        case ERROR_FILE_INVALID: error = ENODEV; break;
  52        case ERROR_FILE_NOT_FOUND: error = ENOENT; break;
  53        case ERROR_GEN_FAILURE: error = EIO; break;
  54        case ERROR_HANDLE_DISK_FULL: error = ENOSPC; break;
  55        case ERROR_INSUFFICIENT_BUFFER: error = ENOMEM; break;
  56        case ERROR_INVALID_ACCESS: error = EACCES; break;
  57        case ERROR_INVALID_ADDRESS: error = EFAULT; break;
  58        case ERROR_INVALID_BLOCK: error = EFAULT; break;
  59        case ERROR_INVALID_DATA: error = EINVAL; break;
  60        case ERROR_INVALID_DRIVE: error = ENODEV; break;
  61        case ERROR_INVALID_EXE_SIGNATURE: error = ENOEXEC; break;
  62        case ERROR_INVALID_FLAGS: error = EINVAL; break;
  63        case ERROR_INVALID_FUNCTION: error = ENOSYS; break;
  64        case ERROR_INVALID_HANDLE: error = EBADF; break;
  65        case ERROR_INVALID_LOGON_HOURS: error = EACCES; break;
  66        case ERROR_INVALID_NAME: error = EINVAL; break;
  67        case ERROR_INVALID_OWNER: error = EINVAL; break;
  68        case ERROR_INVALID_PARAMETER: error = EINVAL; break;
  69        case ERROR_INVALID_PASSWORD: error = EPERM; break;
  70        case ERROR_INVALID_PRIMARY_GROUP: error = EINVAL; break;
  71        case ERROR_INVALID_SIGNAL_NUMBER: error = EINVAL; break;
  72        case ERROR_INVALID_TARGET_HANDLE: error = EIO; break;
  73        case ERROR_INVALID_WORKSTATION: error = EACCES; break;
  74        case ERROR_IO_DEVICE: error = EIO; break;
  75        case ERROR_IO_INCOMPLETE: error = EINTR; break;
  76        case ERROR_LOCKED: error = EBUSY; break;
  77        case ERROR_LOCK_VIOLATION: error = EACCES; break;
  78        case ERROR_LOGON_FAILURE: error = EACCES; break;
  79        case ERROR_MAPPED_ALIGNMENT: error = EINVAL; break;
  80        case ERROR_META_EXPANSION_TOO_LONG: error = E2BIG; break;
  81        case ERROR_MORE_DATA: error = EPIPE; break;
  82        case ERROR_NEGATIVE_SEEK: error = ESPIPE; break;
  83        case ERROR_NOACCESS: error = EFAULT; break;
  84        case ERROR_NONE_MAPPED: error = EINVAL; break;
  85        case ERROR_NOT_ENOUGH_MEMORY: error = ENOMEM; break;
  86        case ERROR_NOT_READY: error = EAGAIN; break;
  87        case ERROR_NOT_SAME_DEVICE: error = EXDEV; break;
  88        case ERROR_NO_DATA: error = EPIPE; break;
  89        case ERROR_NO_MORE_SEARCH_HANDLES: error = EIO; break;
  90        case ERROR_NO_PROC_SLOTS: error = EAGAIN; break;
  91        case ERROR_NO_SUCH_PRIVILEGE: error = EACCES; break;
  92        case ERROR_OPEN_FAILED: error = EIO; break;
  93        case ERROR_OPEN_FILES: error = EBUSY; break;
  94        case ERROR_OPERATION_ABORTED: error = EINTR; break;
  95        case ERROR_OUTOFMEMORY: error = ENOMEM; break;
  96        case ERROR_PASSWORD_EXPIRED: error = EACCES; break;
  97        case ERROR_PATH_BUSY: error = EBUSY; break;
  98        case ERROR_PATH_NOT_FOUND: error = ENOENT; break;
  99        case ERROR_PIPE_BUSY: error = EBUSY; break;
 100        case ERROR_PIPE_CONNECTED: error = EPIPE; break;
 101        case ERROR_PIPE_LISTENING: error = EPIPE; break;
 102        case ERROR_PIPE_NOT_CONNECTED: error = EPIPE; break;
 103        case ERROR_PRIVILEGE_NOT_HELD: error = EACCES; break;
 104        case ERROR_READ_FAULT: error = EIO; break;
 105        case ERROR_SEEK: error = EIO; break;
 106        case ERROR_SEEK_ON_DEVICE: error = ESPIPE; break;
 107        case ERROR_SHARING_BUFFER_EXCEEDED: error = ENFILE; break;
 108        case ERROR_SHARING_VIOLATION: error = EACCES; break;
 109        case ERROR_STACK_OVERFLOW: error = ENOMEM; break;
 110        case ERROR_SWAPERROR: error = ENOENT; break;
 111        case ERROR_TOO_MANY_MODULES: error = EMFILE; break;
 112        case ERROR_TOO_MANY_OPEN_FILES: error = EMFILE; break;
 113        case ERROR_UNRECOGNIZED_MEDIA: error = ENXIO; break;
 114        case ERROR_UNRECOGNIZED_VOLUME: error = ENODEV; break;
 115        case ERROR_WAIT_NO_CHILDREN: error = ECHILD; break;
 116        case ERROR_WRITE_FAULT: error = EIO; break;
 117        case ERROR_WRITE_PROTECT: error = EROFS; break;
 118        }
 119        return error;
 120}
 121
 122static inline int is_file_in_use_error(DWORD errcode)
 123{
 124        switch (errcode) {
 125        case ERROR_SHARING_VIOLATION:
 126        case ERROR_ACCESS_DENIED:
 127                return 1;
 128        }
 129
 130        return 0;
 131}
 132
 133static int read_yes_no_answer(void)
 134{
 135        char answer[1024];
 136
 137        if (fgets(answer, sizeof(answer), stdin)) {
 138                size_t answer_len = strlen(answer);
 139                int got_full_line = 0, c;
 140
 141                /* remove the newline */
 142                if (answer_len >= 2 && answer[answer_len-2] == '\r') {
 143                        answer[answer_len-2] = '\0';
 144                        got_full_line = 1;
 145                } else if (answer_len >= 1 && answer[answer_len-1] == '\n') {
 146                        answer[answer_len-1] = '\0';
 147                        got_full_line = 1;
 148                }
 149                /* flush the buffer in case we did not get the full line */
 150                if (!got_full_line)
 151                        while ((c = getchar()) != EOF && c != '\n')
 152                                ;
 153        } else
 154                /* we could not read, return the
 155                 * default answer which is no */
 156                return 0;
 157
 158        if (tolower(answer[0]) == 'y' && !answer[1])
 159                return 1;
 160        if (!strncasecmp(answer, "yes", sizeof(answer)))
 161                return 1;
 162        if (tolower(answer[0]) == 'n' && !answer[1])
 163                return 0;
 164        if (!strncasecmp(answer, "no", sizeof(answer)))
 165                return 0;
 166
 167        /* did not find an answer we understand */
 168        return -1;
 169}
 170
 171static int ask_yes_no_if_possible(const char *format, ...)
 172{
 173        char question[4096];
 174        const char *retry_hook[] = { NULL, NULL, NULL };
 175        va_list args;
 176
 177        va_start(args, format);
 178        vsnprintf(question, sizeof(question), format, args);
 179        va_end(args);
 180
 181        if ((retry_hook[0] = mingw_getenv("GIT_ASK_YESNO"))) {
 182                retry_hook[1] = question;
 183                return !run_command_v_opt(retry_hook, 0);
 184        }
 185
 186        if (!isatty(_fileno(stdin)) || !isatty(_fileno(stderr)))
 187                return 0;
 188
 189        while (1) {
 190                int answer;
 191                fprintf(stderr, "%s (y/n) ", question);
 192
 193                if ((answer = read_yes_no_answer()) >= 0)
 194                        return answer;
 195
 196                fprintf(stderr, "Sorry, I did not understand your answer. "
 197                                "Please type 'y' or 'n'\n");
 198        }
 199}
 200
 201#undef unlink
 202int mingw_unlink(const char *pathname)
 203{
 204        int ret, tries = 0;
 205
 206        /* read-only files cannot be removed */
 207        chmod(pathname, 0666);
 208        while ((ret = unlink(pathname)) == -1 && tries < ARRAY_SIZE(delay)) {
 209                if (!is_file_in_use_error(GetLastError()))
 210                        break;
 211                /*
 212                 * We assume that some other process had the source or
 213                 * destination file open at the wrong moment and retry.
 214                 * In order to give the other process a higher chance to
 215                 * complete its operation, we give up our time slice now.
 216                 * If we have to retry again, we do sleep a bit.
 217                 */
 218                Sleep(delay[tries]);
 219                tries++;
 220        }
 221        while (ret == -1 && is_file_in_use_error(GetLastError()) &&
 222               ask_yes_no_if_possible("Unlink of file '%s' failed. "
 223                        "Should I try again?", pathname))
 224               ret = unlink(pathname);
 225        return ret;
 226}
 227
 228static int is_dir_empty(const char *path)
 229{
 230        struct strbuf buf = STRBUF_INIT;
 231        WIN32_FIND_DATAA findbuf;
 232        HANDLE handle;
 233
 234        strbuf_addf(&buf, "%s\\*", path);
 235        handle = FindFirstFileA(buf.buf, &findbuf);
 236        if (handle == INVALID_HANDLE_VALUE) {
 237                strbuf_release(&buf);
 238                return GetLastError() == ERROR_NO_MORE_FILES;
 239        }
 240
 241        while (!strcmp(findbuf.cFileName, ".") ||
 242                        !strcmp(findbuf.cFileName, ".."))
 243                if (!FindNextFile(handle, &findbuf)) {
 244                        strbuf_release(&buf);
 245                        return GetLastError() == ERROR_NO_MORE_FILES;
 246                }
 247        FindClose(handle);
 248        strbuf_release(&buf);
 249        return 0;
 250}
 251
 252#undef rmdir
 253int mingw_rmdir(const char *pathname)
 254{
 255        int ret, tries = 0;
 256
 257        while ((ret = rmdir(pathname)) == -1 && tries < ARRAY_SIZE(delay)) {
 258                if (!is_file_in_use_error(GetLastError()))
 259                        break;
 260                if (!is_dir_empty(pathname)) {
 261                        errno = ENOTEMPTY;
 262                        break;
 263                }
 264                /*
 265                 * We assume that some other process had the source or
 266                 * destination file open at the wrong moment and retry.
 267                 * In order to give the other process a higher chance to
 268                 * complete its operation, we give up our time slice now.
 269                 * If we have to retry again, we do sleep a bit.
 270                 */
 271                Sleep(delay[tries]);
 272                tries++;
 273        }
 274        while (ret == -1 && is_file_in_use_error(GetLastError()) &&
 275               ask_yes_no_if_possible("Deletion of directory '%s' failed. "
 276                        "Should I try again?", pathname))
 277               ret = rmdir(pathname);
 278        return ret;
 279}
 280
 281#undef open
 282int mingw_open (const char *filename, int oflags, ...)
 283{
 284        va_list args;
 285        unsigned mode;
 286        int fd;
 287
 288        va_start(args, oflags);
 289        mode = va_arg(args, int);
 290        va_end(args);
 291
 292        if (filename && !strcmp(filename, "/dev/null"))
 293                filename = "nul";
 294
 295        fd = open(filename, oflags, mode);
 296
 297        if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
 298                DWORD attrs = GetFileAttributes(filename);
 299                if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
 300                        errno = EISDIR;
 301        }
 302        return fd;
 303}
 304
 305#undef write
 306ssize_t mingw_write(int fd, const void *buf, size_t count)
 307{
 308        /*
 309         * While write() calls to a file on a local disk are translated
 310         * into WriteFile() calls with a maximum size of 64KB on Windows
 311         * XP and 256KB on Vista, no such cap is placed on writes to
 312         * files over the network on Windows XP.  Unfortunately, there
 313         * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86;
 314         * bigger writes fail on Windows XP.
 315         * So we cap to a nice 31MB here to avoid write failures over
 316         * the net without changing the number of WriteFile() calls in
 317         * the local case.
 318         */
 319        return write(fd, buf, min(count, 31 * 1024 * 1024));
 320}
 321
 322#undef fopen
 323FILE *mingw_fopen (const char *filename, const char *otype)
 324{
 325        if (filename && !strcmp(filename, "/dev/null"))
 326                filename = "nul";
 327        return fopen(filename, otype);
 328}
 329
 330#undef freopen
 331FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
 332{
 333        if (filename && !strcmp(filename, "/dev/null"))
 334                filename = "nul";
 335        return freopen(filename, otype, stream);
 336}
 337
 338/*
 339 * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
 340 * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
 341 */
 342static inline long long filetime_to_hnsec(const FILETIME *ft)
 343{
 344        long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
 345        /* Windows to Unix Epoch conversion */
 346        return winTime - 116444736000000000LL;
 347}
 348
 349static inline time_t filetime_to_time_t(const FILETIME *ft)
 350{
 351        return (time_t)(filetime_to_hnsec(ft) / 10000000);
 352}
 353
 354/* We keep the do_lstat code in a separate function to avoid recursion.
 355 * When a path ends with a slash, the stat will fail with ENOENT. In
 356 * this case, we strip the trailing slashes and stat again.
 357 *
 358 * If follow is true then act like stat() and report on the link
 359 * target. Otherwise report on the link itself.
 360 */
 361static int do_lstat(int follow, const char *file_name, struct stat *buf)
 362{
 363        int err;
 364        WIN32_FILE_ATTRIBUTE_DATA fdata;
 365
 366        if (!(err = get_file_attr(file_name, &fdata))) {
 367                buf->st_ino = 0;
 368                buf->st_gid = 0;
 369                buf->st_uid = 0;
 370                buf->st_nlink = 1;
 371                buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 372                buf->st_size = fdata.nFileSizeLow |
 373                        (((off_t)fdata.nFileSizeHigh)<<32);
 374                buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 375                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 376                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 377                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 378                if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
 379                        WIN32_FIND_DATAA findbuf;
 380                        HANDLE handle = FindFirstFileA(file_name, &findbuf);
 381                        if (handle != INVALID_HANDLE_VALUE) {
 382                                if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
 383                                                (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
 384                                        if (follow) {
 385                                                char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
 386                                                buf->st_size = readlink(file_name, buffer, MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
 387                                        } else {
 388                                                buf->st_mode = S_IFLNK;
 389                                        }
 390                                        buf->st_mode |= S_IREAD;
 391                                        if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
 392                                                buf->st_mode |= S_IWRITE;
 393                                }
 394                                FindClose(handle);
 395                        }
 396                }
 397                return 0;
 398        }
 399        errno = err;
 400        return -1;
 401}
 402
 403/* We provide our own lstat/fstat functions, since the provided
 404 * lstat/fstat functions are so slow. These stat functions are
 405 * tailored for Git's usage (read: fast), and are not meant to be
 406 * complete. Note that Git stat()s are redirected to mingw_lstat()
 407 * too, since Windows doesn't really handle symlinks that well.
 408 */
 409static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 410{
 411        int namelen;
 412        static char alt_name[PATH_MAX];
 413
 414        if (!do_lstat(follow, file_name, buf))
 415                return 0;
 416
 417        /* if file_name ended in a '/', Windows returned ENOENT;
 418         * try again without trailing slashes
 419         */
 420        if (errno != ENOENT)
 421                return -1;
 422
 423        namelen = strlen(file_name);
 424        if (namelen && file_name[namelen-1] != '/')
 425                return -1;
 426        while (namelen && file_name[namelen-1] == '/')
 427                --namelen;
 428        if (!namelen || namelen >= PATH_MAX)
 429                return -1;
 430
 431        memcpy(alt_name, file_name, namelen);
 432        alt_name[namelen] = 0;
 433        return do_lstat(follow, alt_name, buf);
 434}
 435
 436int mingw_lstat(const char *file_name, struct stat *buf)
 437{
 438        return do_stat_internal(0, file_name, buf);
 439}
 440int mingw_stat(const char *file_name, struct stat *buf)
 441{
 442        return do_stat_internal(1, file_name, buf);
 443}
 444
 445#undef fstat
 446int mingw_fstat(int fd, struct stat *buf)
 447{
 448        HANDLE fh = (HANDLE)_get_osfhandle(fd);
 449        BY_HANDLE_FILE_INFORMATION fdata;
 450
 451        if (fh == INVALID_HANDLE_VALUE) {
 452                errno = EBADF;
 453                return -1;
 454        }
 455        /* direct non-file handles to MS's fstat() */
 456        if (GetFileType(fh) != FILE_TYPE_DISK)
 457                return _fstati64(fd, buf);
 458
 459        if (GetFileInformationByHandle(fh, &fdata)) {
 460                buf->st_ino = 0;
 461                buf->st_gid = 0;
 462                buf->st_uid = 0;
 463                buf->st_nlink = 1;
 464                buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
 465                buf->st_size = fdata.nFileSizeLow |
 466                        (((off_t)fdata.nFileSizeHigh)<<32);
 467                buf->st_dev = buf->st_rdev = 0; /* not used by Git */
 468                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 469                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
 470                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
 471                return 0;
 472        }
 473        errno = EBADF;
 474        return -1;
 475}
 476
 477static inline void time_t_to_filetime(time_t t, FILETIME *ft)
 478{
 479        long long winTime = t * 10000000LL + 116444736000000000LL;
 480        ft->dwLowDateTime = winTime;
 481        ft->dwHighDateTime = winTime >> 32;
 482}
 483
 484int mingw_utime (const char *file_name, const struct utimbuf *times)
 485{
 486        FILETIME mft, aft;
 487        int fh, rc;
 488
 489        /* must have write permission */
 490        DWORD attrs = GetFileAttributes(file_name);
 491        if (attrs != INVALID_FILE_ATTRIBUTES &&
 492            (attrs & FILE_ATTRIBUTE_READONLY)) {
 493                /* ignore errors here; open() will report them */
 494                SetFileAttributes(file_name, attrs & ~FILE_ATTRIBUTE_READONLY);
 495        }
 496
 497        if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0) {
 498                rc = -1;
 499                goto revert_attrs;
 500        }
 501
 502        if (times) {
 503                time_t_to_filetime(times->modtime, &mft);
 504                time_t_to_filetime(times->actime, &aft);
 505        } else {
 506                GetSystemTimeAsFileTime(&mft);
 507                aft = mft;
 508        }
 509        if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
 510                errno = EINVAL;
 511                rc = -1;
 512        } else
 513                rc = 0;
 514        close(fh);
 515
 516revert_attrs:
 517        if (attrs != INVALID_FILE_ATTRIBUTES &&
 518            (attrs & FILE_ATTRIBUTE_READONLY)) {
 519                /* ignore errors again */
 520                SetFileAttributes(file_name, attrs);
 521        }
 522        return rc;
 523}
 524
 525unsigned int sleep (unsigned int seconds)
 526{
 527        Sleep(seconds*1000);
 528        return 0;
 529}
 530
 531int mkstemp(char *template)
 532{
 533        char *filename = mktemp(template);
 534        if (filename == NULL)
 535                return -1;
 536        return open(filename, O_RDWR | O_CREAT, 0600);
 537}
 538
 539int gettimeofday(struct timeval *tv, void *tz)
 540{
 541        FILETIME ft;
 542        long long hnsec;
 543
 544        GetSystemTimeAsFileTime(&ft);
 545        hnsec = filetime_to_hnsec(&ft);
 546        tv->tv_sec = hnsec / 10000000;
 547        tv->tv_usec = (hnsec % 10000000) / 10;
 548        return 0;
 549}
 550
 551int pipe(int filedes[2])
 552{
 553        HANDLE h[2];
 554
 555        /* this creates non-inheritable handles */
 556        if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
 557                errno = err_win_to_posix(GetLastError());
 558                return -1;
 559        }
 560        filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
 561        if (filedes[0] < 0) {
 562                CloseHandle(h[0]);
 563                CloseHandle(h[1]);
 564                return -1;
 565        }
 566        filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
 567        if (filedes[0] < 0) {
 568                close(filedes[0]);
 569                CloseHandle(h[1]);
 570                return -1;
 571        }
 572        return 0;
 573}
 574
 575struct tm *gmtime_r(const time_t *timep, struct tm *result)
 576{
 577        /* gmtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 578        memcpy(result, gmtime(timep), sizeof(struct tm));
 579        return result;
 580}
 581
 582struct tm *localtime_r(const time_t *timep, struct tm *result)
 583{
 584        /* localtime() in MSVCRT.DLL is thread-safe, but not reentrant */
 585        memcpy(result, localtime(timep), sizeof(struct tm));
 586        return result;
 587}
 588
 589#undef getcwd
 590char *mingw_getcwd(char *pointer, int len)
 591{
 592        int i;
 593        char *ret = getcwd(pointer, len);
 594        if (!ret)
 595                return ret;
 596        for (i = 0; pointer[i]; i++)
 597                if (pointer[i] == '\\')
 598                        pointer[i] = '/';
 599        return ret;
 600}
 601
 602/*
 603 * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
 604 * (Parsing C++ Command-Line Arguments)
 605 */
 606static const char *quote_arg(const char *arg)
 607{
 608        /* count chars to quote */
 609        int len = 0, n = 0;
 610        int force_quotes = 0;
 611        char *q, *d;
 612        const char *p = arg;
 613        if (!*p) force_quotes = 1;
 614        while (*p) {
 615                if (isspace(*p) || *p == '*' || *p == '?' || *p == '{' || *p == '\'')
 616                        force_quotes = 1;
 617                else if (*p == '"')
 618                        n++;
 619                else if (*p == '\\') {
 620                        int count = 0;
 621                        while (*p == '\\') {
 622                                count++;
 623                                p++;
 624                                len++;
 625                        }
 626                        if (*p == '"')
 627                                n += count*2 + 1;
 628                        continue;
 629                }
 630                len++;
 631                p++;
 632        }
 633        if (!force_quotes && n == 0)
 634                return arg;
 635
 636        /* insert \ where necessary */
 637        d = q = xmalloc(len+n+3);
 638        *d++ = '"';
 639        while (*arg) {
 640                if (*arg == '"')
 641                        *d++ = '\\';
 642                else if (*arg == '\\') {
 643                        int count = 0;
 644                        while (*arg == '\\') {
 645                                count++;
 646                                *d++ = *arg++;
 647                        }
 648                        if (*arg == '"') {
 649                                while (count-- > 0)
 650                                        *d++ = '\\';
 651                                *d++ = '\\';
 652                        }
 653                }
 654                *d++ = *arg++;
 655        }
 656        *d++ = '"';
 657        *d++ = 0;
 658        return q;
 659}
 660
 661static const char *parse_interpreter(const char *cmd)
 662{
 663        static char buf[100];
 664        char *p, *opt;
 665        int n, fd;
 666
 667        /* don't even try a .exe */
 668        n = strlen(cmd);
 669        if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
 670                return NULL;
 671
 672        fd = open(cmd, O_RDONLY);
 673        if (fd < 0)
 674                return NULL;
 675        n = read(fd, buf, sizeof(buf)-1);
 676        close(fd);
 677        if (n < 4)      /* at least '#!/x' and not error */
 678                return NULL;
 679
 680        if (buf[0] != '#' || buf[1] != '!')
 681                return NULL;
 682        buf[n] = '\0';
 683        p = buf + strcspn(buf, "\r\n");
 684        if (!*p)
 685                return NULL;
 686
 687        *p = '\0';
 688        if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
 689                return NULL;
 690        /* strip options */
 691        if ((opt = strchr(p+1, ' ')))
 692                *opt = '\0';
 693        return p+1;
 694}
 695
 696/*
 697 * Splits the PATH into parts.
 698 */
 699static char **get_path_split(void)
 700{
 701        char *p, **path, *envpath = mingw_getenv("PATH");
 702        int i, n = 0;
 703
 704        if (!envpath || !*envpath)
 705                return NULL;
 706
 707        envpath = xstrdup(envpath);
 708        p = envpath;
 709        while (p) {
 710                char *dir = p;
 711                p = strchr(p, ';');
 712                if (p) *p++ = '\0';
 713                if (*dir) {     /* not earlier, catches series of ; */
 714                        ++n;
 715                }
 716        }
 717        if (!n)
 718                return NULL;
 719
 720        path = xmalloc((n+1)*sizeof(char *));
 721        p = envpath;
 722        i = 0;
 723        do {
 724                if (*p)
 725                        path[i++] = xstrdup(p);
 726                p = p+strlen(p)+1;
 727        } while (i < n);
 728        path[i] = NULL;
 729
 730        free(envpath);
 731
 732        return path;
 733}
 734
 735static void free_path_split(char **path)
 736{
 737        char **p = path;
 738
 739        if (!path)
 740                return;
 741
 742        while (*p)
 743                free(*p++);
 744        free(path);
 745}
 746
 747/*
 748 * exe_only means that we only want to detect .exe files, but not scripts
 749 * (which do not have an extension)
 750 */
 751static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
 752{
 753        char path[MAX_PATH];
 754        snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
 755
 756        if (!isexe && access(path, F_OK) == 0)
 757                return xstrdup(path);
 758        path[strlen(path)-4] = '\0';
 759        if ((!exe_only || isexe) && access(path, F_OK) == 0)
 760                if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
 761                        return xstrdup(path);
 762        return NULL;
 763}
 764
 765/*
 766 * Determines the absolute path of cmd using the split path in path.
 767 * If cmd contains a slash or backslash, no lookup is performed.
 768 */
 769static char *path_lookup(const char *cmd, char **path, int exe_only)
 770{
 771        char *prog = NULL;
 772        int len = strlen(cmd);
 773        int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
 774
 775        if (strchr(cmd, '/') || strchr(cmd, '\\'))
 776                prog = xstrdup(cmd);
 777
 778        while (!prog && *path)
 779                prog = lookup_prog(*path++, cmd, isexe, exe_only);
 780
 781        return prog;
 782}
 783
 784static int env_compare(const void *a, const void *b)
 785{
 786        char *const *ea = a;
 787        char *const *eb = b;
 788        return strcasecmp(*ea, *eb);
 789}
 790
 791struct pinfo_t {
 792        struct pinfo_t *next;
 793        pid_t pid;
 794        HANDLE proc;
 795} pinfo_t;
 796struct pinfo_t *pinfo = NULL;
 797CRITICAL_SECTION pinfo_cs;
 798
 799static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
 800                              const char *dir,
 801                              int prepend_cmd, int fhin, int fhout, int fherr)
 802{
 803        STARTUPINFO si;
 804        PROCESS_INFORMATION pi;
 805        struct strbuf envblk, args;
 806        unsigned flags;
 807        BOOL ret;
 808
 809        /* Determine whether or not we are associated to a console */
 810        HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
 811                        FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
 812                        FILE_ATTRIBUTE_NORMAL, NULL);
 813        if (cons == INVALID_HANDLE_VALUE) {
 814                /* There is no console associated with this process.
 815                 * Since the child is a console process, Windows
 816                 * would normally create a console window. But
 817                 * since we'll be redirecting std streams, we do
 818                 * not need the console.
 819                 * It is necessary to use DETACHED_PROCESS
 820                 * instead of CREATE_NO_WINDOW to make ssh
 821                 * recognize that it has no console.
 822                 */
 823                flags = DETACHED_PROCESS;
 824        } else {
 825                /* There is already a console. If we specified
 826                 * DETACHED_PROCESS here, too, Windows would
 827                 * disassociate the child from the console.
 828                 * The same is true for CREATE_NO_WINDOW.
 829                 * Go figure!
 830                 */
 831                flags = 0;
 832                CloseHandle(cons);
 833        }
 834        memset(&si, 0, sizeof(si));
 835        si.cb = sizeof(si);
 836        si.dwFlags = STARTF_USESTDHANDLES;
 837        si.hStdInput = (HANDLE) _get_osfhandle(fhin);
 838        si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
 839        si.hStdError = (HANDLE) _get_osfhandle(fherr);
 840
 841        /* concatenate argv, quoting args as we go */
 842        strbuf_init(&args, 0);
 843        if (prepend_cmd) {
 844                char *quoted = (char *)quote_arg(cmd);
 845                strbuf_addstr(&args, quoted);
 846                if (quoted != cmd)
 847                        free(quoted);
 848        }
 849        for (; *argv; argv++) {
 850                char *quoted = (char *)quote_arg(*argv);
 851                if (*args.buf)
 852                        strbuf_addch(&args, ' ');
 853                strbuf_addstr(&args, quoted);
 854                if (quoted != *argv)
 855                        free(quoted);
 856        }
 857
 858        if (env) {
 859                int count = 0;
 860                char **e, **sorted_env;
 861
 862                for (e = env; *e; e++)
 863                        count++;
 864
 865                /* environment must be sorted */
 866                sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
 867                memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
 868                qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
 869
 870                strbuf_init(&envblk, 0);
 871                for (e = sorted_env; *e; e++) {
 872                        strbuf_addstr(&envblk, *e);
 873                        strbuf_addch(&envblk, '\0');
 874                }
 875                free(sorted_env);
 876        }
 877
 878        memset(&pi, 0, sizeof(pi));
 879        ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
 880                env ? envblk.buf : NULL, dir, &si, &pi);
 881
 882        if (env)
 883                strbuf_release(&envblk);
 884        strbuf_release(&args);
 885
 886        if (!ret) {
 887                errno = ENOENT;
 888                return -1;
 889        }
 890        CloseHandle(pi.hThread);
 891
 892        /*
 893         * The process ID is the human-readable identifier of the process
 894         * that we want to present in log and error messages. The handle
 895         * is not useful for this purpose. But we cannot close it, either,
 896         * because it is not possible to turn a process ID into a process
 897         * handle after the process terminated.
 898         * Keep the handle in a list for waitpid.
 899         */
 900        EnterCriticalSection(&pinfo_cs);
 901        {
 902                struct pinfo_t *info = xmalloc(sizeof(struct pinfo_t));
 903                info->pid = pi.dwProcessId;
 904                info->proc = pi.hProcess;
 905                info->next = pinfo;
 906                pinfo = info;
 907        }
 908        LeaveCriticalSection(&pinfo_cs);
 909
 910        return (pid_t)pi.dwProcessId;
 911}
 912
 913static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 914                           int prepend_cmd)
 915{
 916        return mingw_spawnve_fd(cmd, argv, env, NULL, prepend_cmd, 0, 1, 2);
 917}
 918
 919pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
 920                     const char *dir,
 921                     int fhin, int fhout, int fherr)
 922{
 923        pid_t pid;
 924        char **path = get_path_split();
 925        char *prog = path_lookup(cmd, path, 0);
 926
 927        if (!prog) {
 928                errno = ENOENT;
 929                pid = -1;
 930        }
 931        else {
 932                const char *interpr = parse_interpreter(prog);
 933
 934                if (interpr) {
 935                        const char *argv0 = argv[0];
 936                        char *iprog = path_lookup(interpr, path, 1);
 937                        argv[0] = prog;
 938                        if (!iprog) {
 939                                errno = ENOENT;
 940                                pid = -1;
 941                        }
 942                        else {
 943                                pid = mingw_spawnve_fd(iprog, argv, env, dir, 1,
 944                                                       fhin, fhout, fherr);
 945                                free(iprog);
 946                        }
 947                        argv[0] = argv0;
 948                }
 949                else
 950                        pid = mingw_spawnve_fd(prog, argv, env, dir, 0,
 951                                               fhin, fhout, fherr);
 952                free(prog);
 953        }
 954        free_path_split(path);
 955        return pid;
 956}
 957
 958static int try_shell_exec(const char *cmd, char *const *argv, char **env)
 959{
 960        const char *interpr = parse_interpreter(cmd);
 961        char **path;
 962        char *prog;
 963        int pid = 0;
 964
 965        if (!interpr)
 966                return 0;
 967        path = get_path_split();
 968        prog = path_lookup(interpr, path, 1);
 969        if (prog) {
 970                int argc = 0;
 971                const char **argv2;
 972                while (argv[argc]) argc++;
 973                argv2 = xmalloc(sizeof(*argv) * (argc+1));
 974                argv2[0] = (char *)cmd; /* full path to the script file */
 975                memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
 976                pid = mingw_spawnve(prog, argv2, env, 1);
 977                if (pid >= 0) {
 978                        int status;
 979                        if (waitpid(pid, &status, 0) < 0)
 980                                status = 255;
 981                        exit(status);
 982                }
 983                pid = 1;        /* indicate that we tried but failed */
 984                free(prog);
 985                free(argv2);
 986        }
 987        free_path_split(path);
 988        return pid;
 989}
 990
 991static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
 992{
 993        /* check if git_command is a shell script */
 994        if (!try_shell_exec(cmd, argv, (char **)env)) {
 995                int pid, status;
 996
 997                pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
 998                if (pid < 0)
 999                        return;
1000                if (waitpid(pid, &status, 0) < 0)
1001                        status = 255;
1002                exit(status);
1003        }
1004}
1005
1006void mingw_execvp(const char *cmd, char *const *argv)
1007{
1008        char **path = get_path_split();
1009        char *prog = path_lookup(cmd, path, 0);
1010
1011        if (prog) {
1012                mingw_execve(prog, argv, environ);
1013                free(prog);
1014        } else
1015                errno = ENOENT;
1016
1017        free_path_split(path);
1018}
1019
1020void mingw_execv(const char *cmd, char *const *argv)
1021{
1022        mingw_execve(cmd, argv, environ);
1023}
1024
1025int mingw_kill(pid_t pid, int sig)
1026{
1027        if (pid > 0 && sig == SIGTERM) {
1028                HANDLE h = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
1029
1030                if (TerminateProcess(h, -1)) {
1031                        CloseHandle(h);
1032                        return 0;
1033                }
1034
1035                errno = err_win_to_posix(GetLastError());
1036                CloseHandle(h);
1037                return -1;
1038        }
1039
1040        errno = EINVAL;
1041        return -1;
1042}
1043
1044static char **copy_environ(void)
1045{
1046        char **env;
1047        int i = 0;
1048        while (environ[i])
1049                i++;
1050        env = xmalloc((i+1)*sizeof(*env));
1051        for (i = 0; environ[i]; i++)
1052                env[i] = xstrdup(environ[i]);
1053        env[i] = NULL;
1054        return env;
1055}
1056
1057void free_environ(char **env)
1058{
1059        int i;
1060        for (i = 0; env[i]; i++)
1061                free(env[i]);
1062        free(env);
1063}
1064
1065static int lookup_env(char **env, const char *name, size_t nmln)
1066{
1067        int i;
1068
1069        for (i = 0; env[i]; i++) {
1070                if (0 == strncmp(env[i], name, nmln)
1071                    && '=' == env[i][nmln])
1072                        /* matches */
1073                        return i;
1074        }
1075        return -1;
1076}
1077
1078/*
1079 * If name contains '=', then sets the variable, otherwise it unsets it
1080 */
1081static char **env_setenv(char **env, const char *name)
1082{
1083        char *eq = strchrnul(name, '=');
1084        int i = lookup_env(env, name, eq-name);
1085
1086        if (i < 0) {
1087                if (*eq) {
1088                        for (i = 0; env[i]; i++)
1089                                ;
1090                        env = xrealloc(env, (i+2)*sizeof(*env));
1091                        env[i] = xstrdup(name);
1092                        env[i+1] = NULL;
1093                }
1094        }
1095        else {
1096                free(env[i]);
1097                if (*eq)
1098                        env[i] = xstrdup(name);
1099                else
1100                        for (; env[i]; i++)
1101                                env[i] = env[i+1];
1102        }
1103        return env;
1104}
1105
1106/*
1107 * Copies global environ and adjusts variables as specified by vars.
1108 */
1109char **make_augmented_environ(const char *const *vars)
1110{
1111        char **env = copy_environ();
1112
1113        while (*vars)
1114                env = env_setenv(env, *vars++);
1115        return env;
1116}
1117
1118#undef getenv
1119
1120/*
1121 * The system's getenv looks up the name in a case-insensitive manner.
1122 * This version tries a case-sensitive lookup and falls back to
1123 * case-insensitive if nothing was found.  This is necessary because,
1124 * as a prominent example, CMD sets 'Path', but not 'PATH'.
1125 * Warning: not thread-safe.
1126 */
1127static char *getenv_cs(const char *name)
1128{
1129        size_t len = strlen(name);
1130        int i = lookup_env(environ, name, len);
1131        if (i >= 0)
1132                return environ[i] + len + 1;    /* skip past name and '=' */
1133        return getenv(name);
1134}
1135
1136char *mingw_getenv(const char *name)
1137{
1138        char *result = getenv_cs(name);
1139        if (!result && !strcmp(name, "TMPDIR")) {
1140                /* on Windows it is TMP and TEMP */
1141                result = getenv_cs("TMP");
1142                if (!result)
1143                        result = getenv_cs("TEMP");
1144        }
1145        return result;
1146}
1147
1148/*
1149 * Note, this isn't a complete replacement for getaddrinfo. It assumes
1150 * that service contains a numerical port, or that it is null. It
1151 * does a simple search using gethostbyname, and returns one IPv4 host
1152 * if one was found.
1153 */
1154static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
1155                                   const struct addrinfo *hints,
1156                                   struct addrinfo **res)
1157{
1158        struct hostent *h = NULL;
1159        struct addrinfo *ai;
1160        struct sockaddr_in *sin;
1161
1162        if (node) {
1163                h = gethostbyname(node);
1164                if (!h)
1165                        return WSAGetLastError();
1166        }
1167
1168        ai = xmalloc(sizeof(struct addrinfo));
1169        *res = ai;
1170        ai->ai_flags = 0;
1171        ai->ai_family = AF_INET;
1172        ai->ai_socktype = hints ? hints->ai_socktype : 0;
1173        switch (ai->ai_socktype) {
1174        case SOCK_STREAM:
1175                ai->ai_protocol = IPPROTO_TCP;
1176                break;
1177        case SOCK_DGRAM:
1178                ai->ai_protocol = IPPROTO_UDP;
1179                break;
1180        default:
1181                ai->ai_protocol = 0;
1182                break;
1183        }
1184        ai->ai_addrlen = sizeof(struct sockaddr_in);
1185        if (hints && (hints->ai_flags & AI_CANONNAME))
1186                ai->ai_canonname = h ? xstrdup(h->h_name) : NULL;
1187        else
1188                ai->ai_canonname = NULL;
1189
1190        sin = xmalloc(ai->ai_addrlen);
1191        memset(sin, 0, ai->ai_addrlen);
1192        sin->sin_family = AF_INET;
1193        /* Note: getaddrinfo is supposed to allow service to be a string,
1194         * which should be looked up using getservbyname. This is
1195         * currently not implemented */
1196        if (service)
1197                sin->sin_port = htons(atoi(service));
1198        if (h)
1199                sin->sin_addr = *(struct in_addr *)h->h_addr;
1200        else if (hints && (hints->ai_flags & AI_PASSIVE))
1201                sin->sin_addr.s_addr = INADDR_ANY;
1202        else
1203                sin->sin_addr.s_addr = INADDR_LOOPBACK;
1204        ai->ai_addr = (struct sockaddr *)sin;
1205        ai->ai_next = 0;
1206        return 0;
1207}
1208
1209static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
1210{
1211        free(res->ai_canonname);
1212        free(res->ai_addr);
1213        free(res);
1214}
1215
1216static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
1217                                   char *host, DWORD hostlen,
1218                                   char *serv, DWORD servlen, int flags)
1219{
1220        const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
1221        if (sa->sa_family != AF_INET)
1222                return EAI_FAMILY;
1223        if (!host && !serv)
1224                return EAI_NONAME;
1225
1226        if (host && hostlen > 0) {
1227                struct hostent *ent = NULL;
1228                if (!(flags & NI_NUMERICHOST))
1229                        ent = gethostbyaddr((const char *)&sin->sin_addr,
1230                                            sizeof(sin->sin_addr), AF_INET);
1231
1232                if (ent)
1233                        snprintf(host, hostlen, "%s", ent->h_name);
1234                else if (flags & NI_NAMEREQD)
1235                        return EAI_NONAME;
1236                else
1237                        snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
1238        }
1239
1240        if (serv && servlen > 0) {
1241                struct servent *ent = NULL;
1242                if (!(flags & NI_NUMERICSERV))
1243                        ent = getservbyport(sin->sin_port,
1244                                            flags & NI_DGRAM ? "udp" : "tcp");
1245
1246                if (ent)
1247                        snprintf(serv, servlen, "%s", ent->s_name);
1248                else
1249                        snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
1250        }
1251
1252        return 0;
1253}
1254
1255static HMODULE ipv6_dll = NULL;
1256static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
1257static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
1258                                      const struct addrinfo *hints,
1259                                      struct addrinfo **res);
1260static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
1261                                      char *host, DWORD hostlen,
1262                                      char *serv, DWORD servlen, int flags);
1263/*
1264 * gai_strerror is an inline function in the ws2tcpip.h header, so we
1265 * don't need to try to load that one dynamically.
1266 */
1267
1268static void socket_cleanup(void)
1269{
1270        WSACleanup();
1271        if (ipv6_dll)
1272                FreeLibrary(ipv6_dll);
1273        ipv6_dll = NULL;
1274        ipv6_freeaddrinfo = freeaddrinfo_stub;
1275        ipv6_getaddrinfo = getaddrinfo_stub;
1276        ipv6_getnameinfo = getnameinfo_stub;
1277}
1278
1279static void ensure_socket_initialization(void)
1280{
1281        WSADATA wsa;
1282        static int initialized = 0;
1283        const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
1284        const char **name;
1285
1286        if (initialized)
1287                return;
1288
1289        if (WSAStartup(MAKEWORD(2,2), &wsa))
1290                die("unable to initialize winsock subsystem, error %d",
1291                        WSAGetLastError());
1292
1293        for (name = libraries; *name; name++) {
1294                ipv6_dll = LoadLibrary(*name);
1295                if (!ipv6_dll)
1296                        continue;
1297
1298                ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
1299                        GetProcAddress(ipv6_dll, "freeaddrinfo");
1300                ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
1301                                                   const struct addrinfo *,
1302                                                   struct addrinfo **))
1303                        GetProcAddress(ipv6_dll, "getaddrinfo");
1304                ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
1305                                                   socklen_t, char *, DWORD,
1306                                                   char *, DWORD, int))
1307                        GetProcAddress(ipv6_dll, "getnameinfo");
1308                if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1309                        FreeLibrary(ipv6_dll);
1310                        ipv6_dll = NULL;
1311                } else
1312                        break;
1313        }
1314        if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
1315                ipv6_freeaddrinfo = freeaddrinfo_stub;
1316                ipv6_getaddrinfo = getaddrinfo_stub;
1317                ipv6_getnameinfo = getnameinfo_stub;
1318        }
1319
1320        atexit(socket_cleanup);
1321        initialized = 1;
1322}
1323
1324#undef gethostname
1325int mingw_gethostname(char *name, int namelen)
1326{
1327    ensure_socket_initialization();
1328    return gethostname(name, namelen);
1329}
1330
1331#undef gethostbyname
1332struct hostent *mingw_gethostbyname(const char *host)
1333{
1334        ensure_socket_initialization();
1335        return gethostbyname(host);
1336}
1337
1338void mingw_freeaddrinfo(struct addrinfo *res)
1339{
1340        ipv6_freeaddrinfo(res);
1341}
1342
1343int mingw_getaddrinfo(const char *node, const char *service,
1344                      const struct addrinfo *hints, struct addrinfo **res)
1345{
1346        ensure_socket_initialization();
1347        return ipv6_getaddrinfo(node, service, hints, res);
1348}
1349
1350int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
1351                      char *host, DWORD hostlen, char *serv, DWORD servlen,
1352                      int flags)
1353{
1354        ensure_socket_initialization();
1355        return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
1356}
1357
1358int mingw_socket(int domain, int type, int protocol)
1359{
1360        int sockfd;
1361        SOCKET s;
1362
1363        ensure_socket_initialization();
1364        s = WSASocket(domain, type, protocol, NULL, 0, 0);
1365        if (s == INVALID_SOCKET) {
1366                /*
1367                 * WSAGetLastError() values are regular BSD error codes
1368                 * biased by WSABASEERR.
1369                 * However, strerror() does not know about networking
1370                 * specific errors, which are values beginning at 38 or so.
1371                 * Therefore, we choose to leave the biased error code
1372                 * in errno so that _if_ someone looks up the code somewhere,
1373                 * then it is at least the number that are usually listed.
1374                 */
1375                errno = WSAGetLastError();
1376                return -1;
1377        }
1378        /* convert into a file descriptor */
1379        if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
1380                closesocket(s);
1381                return error("unable to make a socket file descriptor: %s",
1382                        strerror(errno));
1383        }
1384        return sockfd;
1385}
1386
1387#undef connect
1388int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
1389{
1390        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1391        return connect(s, sa, sz);
1392}
1393
1394#undef bind
1395int mingw_bind(int sockfd, struct sockaddr *sa, size_t sz)
1396{
1397        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1398        return bind(s, sa, sz);
1399}
1400
1401#undef setsockopt
1402int mingw_setsockopt(int sockfd, int lvl, int optname, void *optval, int optlen)
1403{
1404        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1405        return setsockopt(s, lvl, optname, (const char*)optval, optlen);
1406}
1407
1408#undef shutdown
1409int mingw_shutdown(int sockfd, int how)
1410{
1411        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1412        return shutdown(s, how);
1413}
1414
1415#undef listen
1416int mingw_listen(int sockfd, int backlog)
1417{
1418        SOCKET s = (SOCKET)_get_osfhandle(sockfd);
1419        return listen(s, backlog);
1420}
1421
1422#undef accept
1423int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
1424{
1425        int sockfd2;
1426
1427        SOCKET s1 = (SOCKET)_get_osfhandle(sockfd1);
1428        SOCKET s2 = accept(s1, sa, sz);
1429
1430        /* convert into a file descriptor */
1431        if ((sockfd2 = _open_osfhandle(s2, O_RDWR|O_BINARY)) < 0) {
1432                int err = errno;
1433                closesocket(s2);
1434                return error("unable to make a socket file descriptor: %s",
1435                        strerror(err));
1436        }
1437        return sockfd2;
1438}
1439
1440#undef rename
1441int mingw_rename(const char *pold, const char *pnew)
1442{
1443        DWORD attrs, gle;
1444        int tries = 0;
1445
1446        /*
1447         * Try native rename() first to get errno right.
1448         * It is based on MoveFile(), which cannot overwrite existing files.
1449         */
1450        if (!rename(pold, pnew))
1451                return 0;
1452        if (errno != EEXIST)
1453                return -1;
1454repeat:
1455        if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1456                return 0;
1457        /* TODO: translate more errors */
1458        gle = GetLastError();
1459        if (gle == ERROR_ACCESS_DENIED &&
1460            (attrs = GetFileAttributes(pnew)) != INVALID_FILE_ATTRIBUTES) {
1461                if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
1462                        errno = EISDIR;
1463                        return -1;
1464                }
1465                if ((attrs & FILE_ATTRIBUTE_READONLY) &&
1466                    SetFileAttributes(pnew, attrs & ~FILE_ATTRIBUTE_READONLY)) {
1467                        if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
1468                                return 0;
1469                        gle = GetLastError();
1470                        /* revert file attributes on failure */
1471                        SetFileAttributes(pnew, attrs);
1472                }
1473        }
1474        if (tries < ARRAY_SIZE(delay) && gle == ERROR_ACCESS_DENIED) {
1475                /*
1476                 * We assume that some other process had the source or
1477                 * destination file open at the wrong moment and retry.
1478                 * In order to give the other process a higher chance to
1479                 * complete its operation, we give up our time slice now.
1480                 * If we have to retry again, we do sleep a bit.
1481                 */
1482                Sleep(delay[tries]);
1483                tries++;
1484                goto repeat;
1485        }
1486        if (gle == ERROR_ACCESS_DENIED &&
1487               ask_yes_no_if_possible("Rename from '%s' to '%s' failed. "
1488                       "Should I try again?", pold, pnew))
1489                goto repeat;
1490
1491        errno = EACCES;
1492        return -1;
1493}
1494
1495/*
1496 * Note that this doesn't return the actual pagesize, but
1497 * the allocation granularity. If future Windows specific git code
1498 * needs the real getpagesize function, we need to find another solution.
1499 */
1500int mingw_getpagesize(void)
1501{
1502        SYSTEM_INFO si;
1503        GetSystemInfo(&si);
1504        return si.dwAllocationGranularity;
1505}
1506
1507struct passwd *getpwuid(int uid)
1508{
1509        static char user_name[100];
1510        static struct passwd p;
1511
1512        DWORD len = sizeof(user_name);
1513        if (!GetUserName(user_name, &len))
1514                return NULL;
1515        p.pw_name = user_name;
1516        p.pw_gecos = "unknown";
1517        p.pw_dir = NULL;
1518        return &p;
1519}
1520
1521static HANDLE timer_event;
1522static HANDLE timer_thread;
1523static int timer_interval;
1524static int one_shot;
1525static sig_handler_t timer_fn = SIG_DFL;
1526
1527/* The timer works like this:
1528 * The thread, ticktack(), is a trivial routine that most of the time
1529 * only waits to receive the signal to terminate. The main thread tells
1530 * the thread to terminate by setting the timer_event to the signalled
1531 * state.
1532 * But ticktack() interrupts the wait state after the timer's interval
1533 * length to call the signal handler.
1534 */
1535
1536static unsigned __stdcall ticktack(void *dummy)
1537{
1538        while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
1539                if (timer_fn == SIG_DFL)
1540                        die("Alarm");
1541                if (timer_fn != SIG_IGN)
1542                        timer_fn(SIGALRM);
1543                if (one_shot)
1544                        break;
1545        }
1546        return 0;
1547}
1548
1549static int start_timer_thread(void)
1550{
1551        timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
1552        if (timer_event) {
1553                timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
1554                if (!timer_thread )
1555                        return errno = ENOMEM,
1556                                error("cannot start timer thread");
1557        } else
1558                return errno = ENOMEM,
1559                        error("cannot allocate resources for timer");
1560        return 0;
1561}
1562
1563static void stop_timer_thread(void)
1564{
1565        if (timer_event)
1566                SetEvent(timer_event);  /* tell thread to terminate */
1567        if (timer_thread) {
1568                int rc = WaitForSingleObject(timer_thread, 1000);
1569                if (rc == WAIT_TIMEOUT)
1570                        error("timer thread did not terminate timely");
1571                else if (rc != WAIT_OBJECT_0)
1572                        error("waiting for timer thread failed: %lu",
1573                              GetLastError());
1574                CloseHandle(timer_thread);
1575        }
1576        if (timer_event)
1577                CloseHandle(timer_event);
1578        timer_event = NULL;
1579        timer_thread = NULL;
1580}
1581
1582static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
1583{
1584        return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
1585}
1586
1587int setitimer(int type, struct itimerval *in, struct itimerval *out)
1588{
1589        static const struct timeval zero;
1590        static int atexit_done;
1591
1592        if (out != NULL)
1593                return errno = EINVAL,
1594                        error("setitimer param 3 != NULL not implemented");
1595        if (!is_timeval_eq(&in->it_interval, &zero) &&
1596            !is_timeval_eq(&in->it_interval, &in->it_value))
1597                return errno = EINVAL,
1598                        error("setitimer: it_interval must be zero or eq it_value");
1599
1600        if (timer_thread)
1601                stop_timer_thread();
1602
1603        if (is_timeval_eq(&in->it_value, &zero) &&
1604            is_timeval_eq(&in->it_interval, &zero))
1605                return 0;
1606
1607        timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
1608        one_shot = is_timeval_eq(&in->it_interval, &zero);
1609        if (!atexit_done) {
1610                atexit(stop_timer_thread);
1611                atexit_done = 1;
1612        }
1613        return start_timer_thread();
1614}
1615
1616int sigaction(int sig, struct sigaction *in, struct sigaction *out)
1617{
1618        if (sig != SIGALRM)
1619                return errno = EINVAL,
1620                        error("sigaction only implemented for SIGALRM");
1621        if (out != NULL)
1622                return errno = EINVAL,
1623                        error("sigaction: param 3 != NULL not implemented");
1624
1625        timer_fn = in->sa_handler;
1626        return 0;
1627}
1628
1629#undef signal
1630sig_handler_t mingw_signal(int sig, sig_handler_t handler)
1631{
1632        sig_handler_t old = timer_fn;
1633        if (sig != SIGALRM)
1634                return signal(sig, handler);
1635        timer_fn = handler;
1636        return old;
1637}
1638
1639static const char *make_backslash_path(const char *path)
1640{
1641        static char buf[PATH_MAX + 1];
1642        char *c;
1643
1644        if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
1645                die("Too long path: %.*s", 60, path);
1646
1647        for (c = buf; *c; c++) {
1648                if (*c == '/')
1649                        *c = '\\';
1650        }
1651        return buf;
1652}
1653
1654void mingw_open_html(const char *unixpath)
1655{
1656        const char *htmlpath = make_backslash_path(unixpath);
1657        typedef HINSTANCE (WINAPI *T)(HWND, const char *,
1658                        const char *, const char *, const char *, INT);
1659        T ShellExecute;
1660        HMODULE shell32;
1661        int r;
1662
1663        shell32 = LoadLibrary("shell32.dll");
1664        if (!shell32)
1665                die("cannot load shell32.dll");
1666        ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
1667        if (!ShellExecute)
1668                die("cannot run browser");
1669
1670        printf("Launching default browser to display HTML ...\n");
1671        r = (int)ShellExecute(NULL, "open", htmlpath, NULL, "\\", SW_SHOWNORMAL);
1672        FreeLibrary(shell32);
1673        /* see the MSDN documentation referring to the result codes here */
1674        if (r <= 32) {
1675                die("failed to launch browser for %.*s", MAX_PATH, unixpath);
1676        }
1677}
1678
1679int link(const char *oldpath, const char *newpath)
1680{
1681        typedef BOOL (WINAPI *T)(const char*, const char*, LPSECURITY_ATTRIBUTES);
1682        static T create_hard_link = NULL;
1683        if (!create_hard_link) {
1684                create_hard_link = (T) GetProcAddress(
1685                        GetModuleHandle("kernel32.dll"), "CreateHardLinkA");
1686                if (!create_hard_link)
1687                        create_hard_link = (T)-1;
1688        }
1689        if (create_hard_link == (T)-1) {
1690                errno = ENOSYS;
1691                return -1;
1692        }
1693        if (!create_hard_link(newpath, oldpath, NULL)) {
1694                errno = err_win_to_posix(GetLastError());
1695                return -1;
1696        }
1697        return 0;
1698}
1699
1700char *getpass(const char *prompt)
1701{
1702        struct strbuf buf = STRBUF_INIT;
1703
1704        fputs(prompt, stderr);
1705        for (;;) {
1706                char c = _getch();
1707                if (c == '\r' || c == '\n')
1708                        break;
1709                strbuf_addch(&buf, c);
1710        }
1711        fputs("\n", stderr);
1712        return strbuf_detach(&buf, NULL);
1713}
1714
1715pid_t waitpid(pid_t pid, int *status, unsigned options)
1716{
1717        HANDLE h = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
1718            FALSE, pid);
1719        if (!h) {
1720                errno = ECHILD;
1721                return -1;
1722        }
1723
1724        if (pid > 0 && options & WNOHANG) {
1725                if (WAIT_OBJECT_0 != WaitForSingleObject(h, 0)) {
1726                        CloseHandle(h);
1727                        return 0;
1728                }
1729                options &= ~WNOHANG;
1730        }
1731
1732        if (options == 0) {
1733                struct pinfo_t **ppinfo;
1734                if (WaitForSingleObject(h, INFINITE) != WAIT_OBJECT_0) {
1735                        CloseHandle(h);
1736                        return 0;
1737                }
1738
1739                if (status)
1740                        GetExitCodeProcess(h, (LPDWORD)status);
1741
1742                EnterCriticalSection(&pinfo_cs);
1743
1744                ppinfo = &pinfo;
1745                while (*ppinfo) {
1746                        struct pinfo_t *info = *ppinfo;
1747                        if (info->pid == pid) {
1748                                CloseHandle(info->proc);
1749                                *ppinfo = info->next;
1750                                free(info);
1751                                break;
1752                        }
1753                        ppinfo = &info->next;
1754                }
1755
1756                LeaveCriticalSection(&pinfo_cs);
1757
1758                CloseHandle(h);
1759                return pid;
1760        }
1761        CloseHandle(h);
1762
1763        errno = EINVAL;
1764        return -1;
1765}