wchar_t * __fgetws_chk (wchar_t *buf, size_t size, int n, _IO_FILE *fp) { _IO_size_t count; wchar_t *result; int old_error; CHECK_FILE (fp, NULL); if (n <= 0) return NULL; _IO_acquire_lock (fp); /* This is very tricky since a file descriptor may be in the non-blocking mode. The error flag doesn't mean much in this case. We return an error only when there is a new error. */ old_error = fp->_IO_file_flags & _IO_ERR_SEEN; fp->_IO_file_flags &= ~_IO_ERR_SEEN; count = _IO_getwline (fp, buf, MIN ((size_t) n - 1, size), L'\n', 1); /* If we read in some bytes and errno is EAGAIN, that error will be reported for next read. */ if (count == 0 || (_IO_ferror_unlocked (fp) && errno != EAGAIN)) result = NULL; else if (count >= size) __chk_fail (); else { buf[count] = '\0'; result = buf; } fp->_IO_file_flags |= old_error; _IO_release_lock (fp); return result; }
wchar_t * fgetws (wchar_t *buf, int n, _IO_FILE *fp) { _IO_size_t count; wchar_t *result; int old_error; CHECK_FILE (fp, NULL); if (n <= 0) return NULL; if (__glibc_unlikely (n == 1)) { /* Another irregular case: since we have to store a NUL byte and there is only room for exactly one byte, we don't have to read anything. */ buf[0] = L'\0'; return buf; } _IO_acquire_lock (fp); /* This is very tricky since a file descriptor may be in the non-blocking mode. The error flag doesn't mean much in this case. We return an error only when there is a new error. */ old_error = fp->_IO_file_flags & _IO_ERR_SEEN; fp->_IO_file_flags &= ~_IO_ERR_SEEN; count = _IO_getwline (fp, buf, n - 1, L'\n', 1); /* If we read in some bytes and errno is EAGAIN, that error will be reported for next read. */ if (count == 0 || (_IO_ferror_unlocked (fp) && errno != EAGAIN)) result = NULL; else { buf[count] = '\0'; result = buf; } fp->_IO_file_flags |= old_error; _IO_release_lock (fp); return result; }