- Fix Catalog JSON table crash when no Jpath

- Added JSON OBJECT specification for pretty != 2.
- Fix NULL values not recognized for nullable JSON columns
- Issue an error message when a JSON table is created without specifying LRECL if PRETTY != 2.
- Make JSONColumns use a TDBJSON class.
- Make JSON table using MAPFAM
modified:
  filamap.h
  filamtxt.h
  ha_connect.cc
  json.result
  tabjson.cpp
  tabjson.h
  table.cpp

- Implementing Discovery for the XML table type.
modified:
  domdoc.cpp
  domdoc.h
  ha_connect.cc
  libdoc.cpp
  plgxml.cpp
  plgxml.h
  reldef.cpp
  reldef.h
  tabxml.cpp
  tabxml.h

- Providing an error message when creating an ODBC table via discovery returns
  columns of more than one table.
modified:
  ha_connect.cc

- TableOptionStruct declaration moved from ha_connect.h to mycat.h
  To make it easier to use by other classes.
modified:
  ha_connect.cc
  ha_connect.h
  mycat.cc
  mycat.h
  reldef.cpp
  tabmysql.cpp
  taboccur.cpp
  tabpivot.cpp
  tabtbl.cpp
  tabutil.cpp
  tabxcl.cpp

storage/connect/tabjson.h

@@ -35,6 +35,8 @@ class JSONDEF : public DOSDEF {                   /* Table description */
   friend class TDBJSON;
   friend class TDBJSN;
   friend class TDBJCL;
+  friend PQRYRES JSONColumns(PGLOBAL, char *, const char *, char *,
+                             int, int, int, bool);
  public:
   // Constructor
   JSONDEF(void);
@@ -71,29 +73,36 @@ class TDBJSN : public TDBDOS {
    TDBJSN(TDBJSN *tdbp);
 
   // Implementation
-  virtual AMT  GetAmType(void) {return TYPE_AM_JSN;}
-  virtual bool SkipHeader(PGLOBAL g);
-  virtual PTDB Duplicate(PGLOBAL g) {return (PTDB)new(g) TDBJSN(this);}
+  virtual AMT   GetAmType(void) {return TYPE_AM_JSN;}
+  virtual bool  SkipHeader(PGLOBAL g);
+  virtual PTDB  Duplicate(PGLOBAL g) {return (PTDB)new(g) TDBJSN(this);}
+          PJSON GetRow(void) {return Row;} 
 
   // Methods
-  virtual PTDB CopyOne(PTABS t);
-  virtual PCOL MakeCol(PGLOBAL g, PCOLDEF cdp, PCOL cprec, int n);
-  virtual PCOL InsertSpecialColumn(PGLOBAL g, PCOL colp);
-  virtual int  RowNumber(PGLOBAL g, bool b = FALSE)
-                {return (b) ? N : Fpos + 1;}
+  virtual PTDB  CopyOne(PTABS t);
+  virtual PCOL  MakeCol(PGLOBAL g, PCOLDEF cdp, PCOL cprec, int n);
+  virtual PCOL  InsertSpecialColumn(PGLOBAL g, PCOL colp);
+  virtual int   RowNumber(PGLOBAL g, bool b = FALSE)
+                 {return (b) ? N : Fpos + 1;}
 
   // Database routines
-  virtual int  Cardinality(PGLOBAL g);
-  virtual int  GetMaxSize(PGLOBAL g);
-  virtual bool OpenDB(PGLOBAL g);
-  virtual bool PrepareWriting(PGLOBAL g);
-  virtual int  ReadDB(PGLOBAL g);
+  virtual int   Cardinality(PGLOBAL g);
+  virtual int   GetMaxSize(PGLOBAL g);
+  virtual bool  OpenDB(PGLOBAL g);
+  virtual bool  PrepareWriting(PGLOBAL g);
+  virtual int   ReadDB(PGLOBAL g);
 
  protected:
+          PJSON FindRow(PGLOBAL g);
+          int   MakeTopTree(PGLOBAL g, PJSON jsp);
+
   // Members
+  PJSON Top;                       // The top JSON tree
   PJSON Row;                       // The current row
+  PJSON Val;                       // The value of the current row
   PJCOL Colp;                      // The multiple column
   JMODE Jmode;                     // MODE_OBJECT by default
+  char *Objname;                   // The table object name
   char *Xcol;                      // Name of expandable column
   int   Fpos;                      // The current row index
 //int   Spos;                      // DELETE start index
@@ -168,6 +177,7 @@ class TDBJSON : public TDBJSN {
   // Implementation
   virtual AMT  GetAmType(void) {return TYPE_AM_JSON;}
   virtual PTDB Duplicate(PGLOBAL g) {return (PTDB)new(g) TDBJSON(this);}
+          PJAR GetDoc(void) {return Doc;} 
 
   // Methods
   virtual PTDB CopyOne(PTABS t);
@@ -185,18 +195,16 @@ class TDBJSON : public TDBJSN {
   virtual int  WriteDB(PGLOBAL g);
   virtual int  DeleteDB(PGLOBAL g, int irc);
   virtual void CloseDB(PGLOBAL g);
+          int  MakeDocument(PGLOBAL g);
 
   // Optimization routines
   virtual int  MakeIndex(PGLOBAL g, PIXDEF pxdf, bool add);
 
  protected:
           int  MakeNewDoc(PGLOBAL g);
-          int  MakeDocument(PGLOBAL g);
 
   // Members
-  PJSON Top;                       // The file JSON tree
   PJAR  Doc;                       // The document array
-  char *Objname;                   // The table object name
   int   Multiple;                  // 0: No 1: DIR 2: Section 3: filelist
   bool  Done;                      // True when document parsing is done
   bool  Changed;                   // After Update, Insert or Delete