#define HAVE_UNISTD_H 11 #define HAVE_SYS_PARAM_H 1 #include #include #if HAVE_UNISTD_H # include #else # include #endif #include #include #include #include #include /* Arrange to define PATH_MAX, like "pathmax.h" does. */ #if HAVE_UNISTD_H # include #endif #include #if defined HAVE_SYS_PARAM_H && !defined PATH_MAX && !defined MAXPATHLEN # include #endif #if !defined PATH_MAX && defined MAXPATHLEN # define PATH_MAX MAXPATHLEN #endif #ifdef __hpux # undef PATH_MAX # define PATH_MAX 1024 #endif #if defined _WIN32 && ! defined __CYGWIN__ # undef PATH_MAX # define PATH_MAX 260 #endif #ifndef AT_FDCWD # define AT_FDCWD 0 #endif #ifdef ENAMETOOLONG # define is_ENAMETOOLONG(x) ((x) == ENAMETOOLONG) #else # define is_ENAMETOOLONG(x) 0 #endif /* Use the getcwd function, not any macro. */ #undef getcwd #if defined _WIN32 && !defined __CYGWIN__ #define access _access #define chdir _chdir #define chmod _chmod #define close _close #define creat _creat #define dup _dup #define dup2 _dup2 #define ecvt _ecvt #define execl _execl #define execle _execle #define execlp _execlp #define execv _execv #define execve _execve #define execvp _execvp #define execvpe _execvpe #define fcloseall _fcloseall #define fcvt _fcvt #define fdopen _fdopen #define fileno _fileno #define gcvt _gcvt #define getcwd _getcwd #define getpid _getpid #define getw _getw #define isatty _isatty #define j0 _j0 #define j1 _j1 #define jn _jn #define lfind _lfind #define lsearch _lsearch #define lseek _lseek #define memccpy _memccpy #define mkdir _mkdir #define mktemp _mktemp #define open _open #define putenv _putenv #define putw _putw #define read _read #define rmdir _rmdir #define strdup _strdup #define swab _swab #define tempnam _tempnam #define tzset _tzset #define umask _umask #define unlink _unlink #define utime _utime #define wcsdup _wcsdup #define write _write #define y0 _y0 #define y1 _y1 #define yn _yn #endif #ifndef S_IRWXU # define S_IRWXU 0700 #endif /* The length of this name must be 8. */ #define DIR_NAME "confdir3" #define DIR_NAME_LEN 8 #define DIR_NAME_SIZE (DIR_NAME_LEN + 1) /* The length of "../". */ #define DOTDOTSLASH_LEN 3 /* Leftover bytes in the buffer, to work around library or OS bugs. */ #define BUF_SLOP 20 int main () { #ifndef PATH_MAX /* The Hurd doesn't define this, so getcwd can't exhibit the bug -- at least not on a local file system. And if we were to start worrying about remote file systems, we'd have to enable the wrapper function all of the time, just to be safe. That's not worth the cost. */ exit (0); #elif ((INT_MAX / (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1) \ - DIR_NAME_SIZE - BUF_SLOP) \ <= PATH_MAX) /* FIXME: Assuming there's a system for which this is true, this should be done in a compile test. */ exit (0); #else char buf[PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN + 1) + DIR_NAME_SIZE + BUF_SLOP]; char *cwd = getcwd (buf, PATH_MAX); size_t initial_cwd_len; size_t cwd_len; int fail = 0; size_t n_chdirs = 0; if (cwd == NULL) exit (10); cwd_len = initial_cwd_len = strlen (cwd); while (1) { size_t dotdot_max = PATH_MAX * (DIR_NAME_SIZE / DOTDOTSLASH_LEN); char *c = NULL; cwd_len += DIR_NAME_SIZE; /* If mkdir or chdir fails, it could be that this system cannot create any file with an absolute name longer than PATH_MAX, such as cygwin. If so, leave fail as 0, because the current working directory can't be too long for getcwd if it can't even be created. On Linux with the 9p file system, mkdir fails with error EINVAL when cwd_len gets too long; ignore this failure because the getcwd() system call produces good results whereas the gnulib substitute calls getdents64 which fails with error EPROTO. For other errors, be pessimistic and consider that as a failure, too. */ if (mkdir (DIR_NAME, S_IRWXU) < 0 || chdir (DIR_NAME) < 0) { if (! (errno == ERANGE || is_ENAMETOOLONG (errno))) #ifdef __linux__ if (! (errno == EINVAL)) #endif fail = 20; break; } if (PATH_MAX <= cwd_len && cwd_len < PATH_MAX + DIR_NAME_SIZE) { struct stat sb; c = getcwd (buf, PATH_MAX); if (!c && errno == ENOENT) { fail = 11; break; } if (c) { fail = 31; break; } if (! (errno == ERANGE || is_ENAMETOOLONG (errno))) { fail = 21; break; } /* Our replacement needs to be able to stat() long ../../paths, so generate a path larger than PATH_MAX to check, avoiding the replacement if we can't stat(). */ c = getcwd (buf, cwd_len + 1); if (c && !AT_FDCWD && stat (c, &sb) != 0 && is_ENAMETOOLONG (errno)) { fail = 32; break; } } if (dotdot_max <= cwd_len - initial_cwd_len) { if (dotdot_max + DIR_NAME_SIZE < cwd_len - initial_cwd_len) break; c = getcwd (buf, cwd_len + 1); if (!c) { if (! (errno == ERANGE || errno == ENOENT || is_ENAMETOOLONG (errno))) { fail = 22; break; } if (AT_FDCWD || errno == ERANGE || errno == ENOENT) { fail = 12; break; } } } if (c && strlen (c) != cwd_len) { fail = 23; break; } ++n_chdirs; } /* Leaving behind such a deep directory is not polite. So clean up here, right away, even though the driving shell script would also clean up. */ { size_t i; /* Try rmdir first, in case the chdir failed. */ rmdir (DIR_NAME); for (i = 0; i <= n_chdirs; i++) { if (chdir ("..") < 0) break; if (rmdir (DIR_NAME) != 0) break; } } exit (fail); #endif }