Compression algo dependencies, still need hackery...

depends/lzma/wrapper/common_internal.h

@@ -0,0 +1,60 @@
+#ifndef __ELZMA_COMMON_INTERNAL_H__
+#define __ELZMA_COMMON_INTERNAL_H__
+
+#include "common.h"
+
+/** a structure which may be cast and passed into Igor's allocate
+ *  routines */
+struct elzma_alloc_struct
+{
+	void *(*Alloc)(void *p, size_t size);
+	void (*Free)(void *p, void *address); /* address can be 0 */
+
+	elzma_malloc clientMallocFunc;
+	void *clientMallocContext;
+
+	elzma_free clientFreeFunc;
+	void *clientFreeContext;
+};
+
+/* initialize an allocation structure, may be called safely multiple
+ * times */
+void init_alloc_struct(struct elzma_alloc_struct *allocStruct, elzma_malloc clientMallocFunc,
+					   void *clientMallocContext, elzma_free clientFreeFunc,
+					   void *clientFreeContext);
+
+/** superset representation of a compressed file header */
+struct elzma_file_header
+{
+	unsigned char pb;
+	unsigned char lp;
+	unsigned char lc;
+	unsigned char isStreamed;
+	long long unsigned int uncompressedSize;
+	unsigned int dictSize;
+};
+
+/** superset representation of a compressed file footer */
+struct elzma_file_footer
+{
+	unsigned int crc32;
+	long long unsigned int uncompressedSize;
+};
+
+/** a structure which encapsulates information about the particular
+ *  file header and footer in use (lzip vs lzma vs (eventually) xz.
+ *  The intention of this structure is to simplify compression and
+ *  decompression logic by abstracting the file format details a bit.  */
+struct elzma_format_handler
+{
+	unsigned int header_size;
+	void (*init_header)(struct elzma_file_header *hdr);
+	int (*parse_header)(const unsigned char *hdrBuf, struct elzma_file_header *hdr);
+	int (*serialize_header)(unsigned char *hdrBuf, const struct elzma_file_header *hdr);
+
+	unsigned int footer_size;
+	int (*serialize_footer)(struct elzma_file_footer *ftr, unsigned char *ftrBuf);
+	int (*parse_footer)(const unsigned char *ftrBuf, struct elzma_file_footer *ftr);
+};
+
+#endif