示例#1
0
文件: f-modify.c 项目: rgchris/ren-c
//
//  Modify_String: C
// 
// Returns new dst_idx.
//
REBCNT Modify_String(
    REBCNT action,          // INSERT, APPEND, CHANGE
    REBSER *dst_ser,        // target
    REBCNT dst_idx,         // position
    const REBVAL *src_val,  // source
    REBFLGS flags,          // AN_PART
    REBINT dst_len,         // length to remove
    REBINT dups             // dup count
) {
    REBSER *src_ser = 0;
    REBCNT src_idx = 0;
    REBCNT src_len;
    REBCNT tail  = SER_LEN(dst_ser);
    REBINT size;        // total to insert
    REBOOL needs_free;
    REBINT limit;

    // For INSERT/PART and APPEND/PART
    if (action != SYM_CHANGE && GET_FLAG(flags, AN_PART))
        limit = dst_len; // should be non-negative
    else
        limit = -1;

    if (limit == 0 || dups < 0) return (action == SYM_APPEND) ? 0 : dst_idx;
    if (action == SYM_APPEND || dst_idx > tail) dst_idx = tail;

    // If the src_val is not a string, then we need to create a string:
    if (GET_FLAG(flags, AN_SERIES)) { // used to indicate a BINARY series
        if (IS_INTEGER(src_val)) {
            src_ser = Make_Series_Codepoint(Int8u(src_val));
            needs_free = TRUE;
            limit = -1;
        }
        else if (IS_BLOCK(src_val)) {
            src_ser = Join_Binary(src_val, limit); // NOTE: it's the shared FORM buffer!
            needs_free = FALSE;
            limit = -1;
        }
        else if (IS_CHAR(src_val)) {
            //
            // "UTF-8 was originally specified to allow codepoints with up to
            // 31 bits (or 6 bytes). But with RFC3629, this was reduced to 4
            // bytes max. to be more compatible to UTF-16."  So depending on
            // which RFC you consider "the UTF-8", max size is either 4 or 6.
            //
            src_ser = Make_Binary(6);
            SET_SERIES_LEN(
                src_ser,
                Encode_UTF8_Char(BIN_HEAD(src_ser), VAL_CHAR(src_val))
            );
            needs_free = TRUE;
            limit = -1;
        }
        else if (ANY_STRING(src_val)) {
            src_len = VAL_LEN_AT(src_val);
            if (limit >= 0 && src_len > cast(REBCNT, limit))
                src_len = limit;
            src_ser = Make_UTF8_From_Any_String(src_val, src_len, 0);
            needs_free = TRUE;
            limit = -1;
        }
        else if (!IS_BINARY(src_val))
            fail (Error_Invalid_Arg(src_val));
    }
    else if (IS_CHAR(src_val)) {
        src_ser = Make_Series_Codepoint(VAL_CHAR(src_val));
        needs_free = TRUE;
    }
    else if (IS_BLOCK(src_val)) {
        src_ser = Form_Tight_Block(src_val);
        needs_free = TRUE;
    }
    else if (!ANY_STRING(src_val) || IS_TAG(src_val)) {
        src_ser = Copy_Form_Value(src_val, 0);
        needs_free = TRUE;
    }

    // Use either new src or the one that was passed:
    if (src_ser) {
        src_len = SER_LEN(src_ser);
    }
    else {
        src_ser = VAL_SERIES(src_val);
        src_idx = VAL_INDEX(src_val);
        src_len = VAL_LEN_AT(src_val);
        needs_free = FALSE;
    }

    if (limit >= 0) src_len = limit;

    // If Source == Destination we need to prevent possible conflicts.
    // Clone the argument just to be safe.
    // (Note: It may be possible to optimize special cases like append !!)
    if (dst_ser == src_ser) {
        assert(!needs_free);
        src_ser = Copy_Sequence_At_Len(src_ser, src_idx, src_len);
        needs_free = TRUE;
        src_idx = 0;
    }

    // Total to insert:
    size = dups * src_len;

    if (action != SYM_CHANGE) {
        // Always expand dst_ser for INSERT and APPEND actions:
        Expand_Series(dst_ser, dst_idx, size);
    } else {
        if (size > dst_len)
            Expand_Series(dst_ser, dst_idx, size - dst_len);
        else if (size < dst_len && GET_FLAG(flags, AN_PART))
            Remove_Series(dst_ser, dst_idx, dst_len - size);
        else if (size + dst_idx > tail) {
            EXPAND_SERIES_TAIL(dst_ser, size - (tail - dst_idx));
        }
    }

    // For dup count:
    for (; dups > 0; dups--) {
        Insert_String(dst_ser, dst_idx, src_ser, src_idx, src_len, TRUE);
        dst_idx += src_len;
    }

    TERM_SEQUENCE(dst_ser);

    if (needs_free) {
        // If we did not use the series that was passed in, but rather
        // created an internal temporary one, we need to free it.
        Free_Series(src_ser);
    }

    return (action == SYM_APPEND) ? 0 : dst_idx;
}
示例#2
0
文件: f-modify.c 项目: mbk/ren-c
*/	REBCNT Modify_String(REBCNT action, REBSER *dst_ser, REBCNT dst_idx, const REBVAL *src_val, REBCNT flags, REBINT dst_len, REBINT dups)
/*
**		action: INSERT, APPEND, CHANGE
**
**		dst_ser:	target
**		dst_idx:	position
**		src_val:	source
**		flags:		AN_PART
**		dst_len:	length to remove
**		dups:		dup count
**
**		return: new dst_idx
**
***********************************************************************/
{
	REBSER *src_ser = 0;
	REBCNT src_idx = 0;
	REBCNT src_len;
	REBCNT tail  = SERIES_TAIL(dst_ser);
	REBINT size;		// total to insert

	if (dups < 0) return (action == A_APPEND) ? 0 : dst_idx;
	if (action == A_APPEND || dst_idx > tail) dst_idx = tail;

	// If the src_val is not a string, then we need to create a string:
	if (GET_FLAG(flags, AN_SERIES)) { // used to indicate a BINARY series
		if (IS_INTEGER(src_val)) {
			src_ser = Append_Byte(0, Int8u(src_val)); // creates a binary
		}
		else if (IS_BLOCK(src_val)) {
			src_ser = Join_Binary(src_val); // NOTE: it's the shared FORM buffer!
		}
		else if (IS_CHAR(src_val)) {
			src_ser = Make_Binary(6); // (I hate unicode)
			src_ser->tail = Encode_UTF8_Char(BIN_HEAD(src_ser), VAL_CHAR(src_val));
		}
		else if (!ANY_BINSTR(src_val)) Trap_Arg_DEAD_END(src_val);
	}
	else if (IS_CHAR(src_val)) {
		src_ser = Append_Byte(0, VAL_CHAR(src_val)); // unicode ok too
	}
	else if (IS_BLOCK(src_val)) {
		src_ser = Form_Tight_Block(src_val);
	}
	else if (!ANY_STR(src_val) || IS_TAG(src_val)) {
		src_ser = Copy_Form_Value(src_val, 0);
	}

	// Use either new src or the one that was passed:
	if (src_ser) {
		src_len = SERIES_TAIL(src_ser);
	}
	else {
		src_ser = VAL_SERIES(src_val);
		src_idx = VAL_INDEX(src_val);
		src_len = VAL_LEN(src_val);
	}

	// For INSERT or APPEND with /PART use the dst_len not src_len:
	if (action != A_CHANGE && GET_FLAG(flags, AN_PART)) src_len = dst_len;

	// If Source == Destination we need to prevent possible conflicts.
	// Clone the argument just to be safe.
	// (Note: It may be possible to optimize special cases like append !!)
	if (dst_ser == src_ser) {
		src_ser = Copy_Series_Part(src_ser, src_idx, src_len);
		src_idx = 0;
	}

	// Total to insert:
	size = dups * src_len;

	if (action != A_CHANGE) {
		// Always expand dst_ser for INSERT and APPEND actions:
		Expand_Series(dst_ser, dst_idx, size);
	} else {
		if (size > dst_len)
			Expand_Series(dst_ser, dst_idx, size - dst_len);
		else if (size < dst_len && GET_FLAG(flags, AN_PART))
			Remove_Series(dst_ser, dst_idx, dst_len - size);
		else if (size + dst_idx > tail) {
			EXPAND_SERIES_TAIL(dst_ser, size - (tail - dst_idx));
		}
	}

	// For dup count:
	for (; dups > 0; dups--) {
		Insert_String(dst_ser, dst_idx, src_ser, src_idx, src_len, TRUE);
		dst_idx += src_len;
	}

	TERM_SERIES(dst_ser);

	return (action == A_APPEND) ? 0 : dst_idx;
}