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); }