FEAT: optional LZW compression method

Author: Oldes

make/rebol3.nest

@@ -656,6 +656,11 @@ include-lzma-compression: [
 	core-files: %core/u-lzma.c
 ]
 
+include-lzw-compression: [
+	config: INCLUDE_LZW
+	core-files: %core/u-lzw.c
+]
+
 include-crush-compression: [
 	config: INCLUDE_CRUSH
 	core-files: %core/u-crush.c
@@ -792,6 +797,7 @@ include-rebol-bulk: [
 	:include-optional-checksums
 	:include-image-natives
 	:include-lzma-compression
+	:include-lzw-compression
 	:include-crush-compression
 	:include-base36-encoding
 	:include-base85-encoding

src/core/n-strings.c

@@ -349,6 +349,13 @@ static struct digest {
 		Set_Binary(D_RET, CompressLzma(ser, index, (REBINT)len, ref_level ? VAL_INT32(level) : -1));
 #else
 		Trap0(RE_FEATURE_NA);
+#endif
+		break;
+	case SYM_LZW:
+#ifdef INCLUDE_LZW
+		Set_Binary(D_RET, CompressLzw(ser, index, (REBINT)len, ref_level ? VAL_INT32(level) : -1));
+#else
+		Trap0(RE_FEATURE_NA);
 #endif
 		break;
 	case SYM_CRUSH:
@@ -415,6 +422,13 @@ static struct digest {
 		Set_Binary(D_RET, DecompressLzma(VAL_SERIES(data), VAL_INDEX(data), (REBINT)len, limit));
 #else
 		Trap0(RE_FEATURE_NA);
+#endif
+		break;
+	case SYM_LZW:
+#ifdef INCLUDE_LZW
+		Set_Binary(D_RET, DecompressLzw(VAL_SERIES(data), VAL_INDEX(data), (REBINT)len, limit));
+#else
+		Trap0(RE_FEATURE_NA);
 #endif
 		break;
 	case SYM_CRUSH: