/*
- * LiZzaRd -- Fast compression method based on Lempel-Ziv 77
+ * LiZaRd -- Fast compression method based on Lempel-Ziv 77
*
* (c) 2004, Robert Spalek <robert@ucw.cz>
*
- * The file format is based on LZO1X and
- * the compression method is based on zlib.
+ * This software may be freely distributed and used according to the terms
+ * of the GNU Lesser General Public License.
*/
-#define LIZZARD_MAX_PROLONG_FACTOR 129/128
- /* Incompressible string of length 256 has a 2-byte header.
- * Hence the scheme the file length get multiplied by 129/128 in the worst
- * case + at most 4 bytes are added for header and EOF. */
+#define LIZARD_NEEDS_CHARS 8
+ /* The compression routine needs input buffer 8 characters longer, because it
+ * does not check the input bounds all the time. */
+#define LIZARD_MAX_MULTIPLY 23./22
+#define LIZARD_MAX_ADD 4
+ /* In the worst case, the compressed file will not be longer than its
+ * original length * 23/22 + 4.
+ *
+ * The additive constant is for EOF and the header of the file.
+ *
+ * The multiplicative constant comes from 19-byte incompressible string
+ * followed by a 3-sequence that can be compressed into 2-byte link. This
+ * breaks the copy-mode and it needs to be restarted with a new header. The
+ * total length is 2(header) + 19(string) + 2(link) = 23.
+ */
-int lizzard_compress(byte *in, uns in_len, byte *out);
-int lizzard_decompress(byte *in, byte *out);
+/* lizard.c */
+int lizard_compress(byte *in, uns in_len, byte *out);
+int lizard_decompress(byte *in, byte *out);
+
+/* lizard-safe.c */
+struct lizard_buffer;
+
+struct lizard_buffer *lizard_alloc(void);
+void lizard_free(struct lizard_buffer *buf);
+byte *lizard_decompress_safe(byte *in, struct lizard_buffer *buf, uns expected_length);