- Fix MDEV-22571 and MDEV-22572. Allow multiple ZIP table

  and enable using special column in them.
  modified:   storage/connect/tabzip.cpp
  modified:   storage/connect/tabzip.h

- Fix some compiler errors
  modified:   storage/connect/tabcmg.cpp

storage/connect/tabcmg.cpp

@@ -26,6 +26,8 @@
 #include "tabmul.h"
 #include "filter.h"
 
+PQRYRES MGOColumns(PGLOBAL g, PCSZ db, PCSZ uri, PTOS topt, bool info);
+
 /* -------------------------- Class CMGDISC -------------------------- */
 
 /***********************************************************************/

storage/connect/tabzip.cpp

@@ -23,6 +23,7 @@
 #include "filamzip.h"
 #include "resource.h"                        // for IDS_COLUMNS
 #include "tabdos.h"
+#include "tabmul.h"
 #include "tabzip.h"
 
 /* -------------------------- Class ZIPDEF --------------------------- */
@@ -41,7 +42,14 @@ bool ZIPDEF::DefineAM(PGLOBAL g, LPCSTR am, int poff)
 /***********************************************************************/
 PTDB ZIPDEF::GetTable(PGLOBAL g, MODE m)
 {
-	return new(g) TDBZIP(this);
+	PTDB tdbp = NULL;
+
+	tdbp = new(g) TDBZIP(this);
+
+	if (Multiple)
+		tdbp = new(g) TDBMUL(tdbp);
+
+	return tdbp;
 } // end of GetTable
 
 /* ------------------------------------------------------------------- */
@@ -108,7 +116,7 @@ int TDBZIP::Cardinality(PGLOBAL g)
 
 			Cardinal = (err == UNZ_OK) ? (int)ginfo.number_entry : 0;
 		} else
-			Cardinal = 0;
+			Cardinal = 10;    // Dummy for multiple tables
 
 	} // endif Cardinal
 
@@ -187,6 +195,7 @@ int TDBZIP::DeleteDB(PGLOBAL g, int irc)
 void TDBZIP::CloseDB(PGLOBAL g)
 {
 	close();
+	nexterr = UNZ_OK;               // For multiple tables
 	Use = USE_READY;                // Just to be clean
 } // end of CloseDB
 

storage/connect/tabzip.h

@@ -48,6 +48,8 @@ class DllExport TDBZIP : public TDBASE {
 
 	// Implementation
 	virtual AMT  GetAmType(void) {return TYPE_AM_ZIP;}
+	virtual PCSZ GetFile(PGLOBAL) {return zfn;}
+	virtual void SetFile(PGLOBAL, PCSZ fn) {zfn = fn;}
 
 	// Methods
 	virtual PCOL MakeCol(PGLOBAL g, PCOLDEF cdp, PCOL cprec, int n);