/* * xgetcwd.c -- return current directory with unlimited length * Copyright (C) 1992, 1996 Free Software Foundation, Inc. * Written by David MacKenzie <djm@gnu.ai.mit.edu>. * * Special function for busybox written by Vladimir Oleynik <vodz@usa.net> */ #include <stdlib.h> #include <errno.h> #include <unistd.h> #include <limits.h> #include <sys/param.h> #include "libbb.h" /* Amount to increase buffer size by in each try. */ #define PATH_INCR 32 /* Return the current directory, newly allocated, arbitrarily long. Return NULL and set errno on error. If argument is not NULL (previous usage allocate memory), call free() */ char * xgetcwd (char *cwd) { char *ret; unsigned path_max; errno = 0; path_max = (unsigned) PATH_MAX; path_max += 2; /* The getcwd docs say to do this. */ if(cwd==0) cwd = xmalloc (path_max); errno = 0; while ((ret = getcwd (cwd, path_max)) == NULL && errno == ERANGE) { path_max += PATH_INCR; cwd = xrealloc (cwd, path_max); errno = 0; } if (ret == NULL) { int save_errno = errno; free (cwd); errno = save_errno; perror_msg("getcwd()"); return NULL; } return cwd; }