void
TextTermStepper_Write_Delta_IMP(TextTermStepper *self, OutStream *outstream,
Obj *value) {
TextTermStepperIVARS *const ivars = TextTermStepper_IVARS(self);
CharBuf *charbuf = (CharBuf*)ivars->value;
const char *last_text = CB_Get_Ptr8(charbuf);
size_t last_size = CB_Get_Size(charbuf);
const char *new_text = NULL;
size_t new_size = 0;
if (Obj_is_a(value, STRING)) {
String *new_string = (String*)value;
new_text = Str_Get_Ptr8(new_string);
new_size = Str_Get_Size(new_string);
}
else if (Obj_is_a(value, CHARBUF)) {
CharBuf *new_charbuf = (CharBuf*)value;
new_text = CB_Get_Ptr8(new_charbuf);
new_size = CB_Get_Size(new_charbuf);
}
else {
THROW(ERR, "'value' must be a String or CharBuf");
}
// Count how many bytes the strings share at the top.
const int32_t overlap = StrHelp_overlap(last_text, new_text,
last_size, new_size);
const char *const diff_start_str = new_text + overlap;
const size_t diff_len = new_size - overlap;
// Write number of common bytes and common bytes.
OutStream_Write_C32(outstream, overlap);
OutStream_Write_String(outstream, diff_start_str, diff_len);
// Update value.
CB_Mimic_Utf8(charbuf, new_text, new_size);
// Invalidate string.
DECREF(ivars->string);
ivars->string = NULL;
}
void
TextTermStepper_write_delta(TextTermStepper *self, OutStream *outstream,
Obj *value)
{
CharBuf *new_value = (CharBuf*)CERTIFY(value, CHARBUF);
CharBuf *last_value = (CharBuf*)self->value;
char *new_text = (char*)CB_Get_Ptr8(new_value);
size_t new_size = CB_Get_Size(new_value);
char *last_text = (char*)CB_Get_Ptr8(last_value);
size_t last_size = CB_Get_Size(last_value);
// Count how many bytes the strings share at the top.
const int32_t overlap = StrHelp_overlap(last_text, new_text,
last_size, new_size);
const char *const diff_start_str = new_text + overlap;
const size_t diff_len = new_size - overlap;
// Write number of common bytes and common bytes.
OutStream_Write_C32(outstream, overlap);
OutStream_Write_String(outstream, diff_start_str, diff_len);
// Update value.
CB_Mimic((CharBuf*)self->value, value);
}
