void
Err_throw_mess(VTable *vtable, CharBuf *message) {
Err_Make_t make
= METHOD_PTR(CERTIFY(vtable, VTABLE), Cfish_Err_Make);
Err *err = (Err*)CERTIFY(make(NULL), ERR);
Err_Cat_Mess(err, message);
DECREF(message);
Err_do_throw(err);
}
static void
S_fill(InStream *self, int64_t amount) {
InStreamIVARS *const ivars = InStream_IVARS(self);
FileWindow *const window = ivars->window;
const int64_t virtual_file_pos = SI_tell(self);
const int64_t real_file_pos = virtual_file_pos + ivars->offset;
const int64_t remaining = ivars->len - virtual_file_pos;
// Throw an error if the requested amount would take us beyond EOF.
if (amount > remaining) {
THROW(ERR, "Read past EOF of %o (pos: %u64 len: %u64 request: %u64)",
ivars->filename, virtual_file_pos, ivars->len, amount);
}
// Make the request.
if (FH_Window(ivars->file_handle, window, real_file_pos, amount)) {
char *fw_buf = FileWindow_Get_Buf(window);
int64_t fw_offset = FileWindow_Get_Offset(window);
int64_t fw_len = FileWindow_Get_Len(window);
char *const window_limit = fw_buf + fw_len;
ivars->buf = fw_buf
- fw_offset // theoretical start of real file
+ ivars->offset // top of virtual file
+ virtual_file_pos; // position within virtual file
ivars->limit = window_limit - ivars->buf > remaining
? ivars->buf + remaining
: window_limit;
}
else {
Err *error = Err_get_error();
String *str = Str_newf(" (%o)", ivars->filename);
Err_Cat_Mess(error, str);
DECREF(str);
RETHROW(INCREF(error));
}
}
