libtclsqlite3.la:	tclsqlite.lo libsqlite3.la
	$(LTLINK) -no-undefined -o $@ tclsqlite.lo \
		libsqlite3.la @TCL_STUB_LIB_SPEC@ $(TLIBS) \
		-rpath "$(TCLLIBDIR)" \
		-version-info "8:6:8" \
		-avoid-version

sqlite3$(TEXE):	$(TOP)/src/shell.c libsqlite3.la sqlite3.h
	$(LTLINK) $(READLINE_FLAGS) \
		-o $@ $(TOP)/src/shell.c libsqlite3.la \
		$(LIBREADLINE) $(TLIBS) -rpath "$(libdir)"

sqldiff$(TEXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS)

fuzzershell$(TEXE):	$(TOP)/tool/fuzzershell.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/fuzzershell.c sqlite3.c $(TLIBS)

libtclsqlite3.la:	tclsqlite.lo libsqlite3.la
	$(LTLINK) -no-undefined -o $@ tclsqlite.lo \
		libsqlite3.la @TCL_STUB_LIB_SPEC@ $(TLIBS) \
		-rpath "$(TCLLIBDIR)" \
		-version-info "8:6:8" \
		-avoid-version

sqlite3$(TEXE):	$(TOP)/src/shell.c libsqlite3.la sqlite3.h $(TOP)/ext/misc/json1.c
	$(LTLINK) $(READLINE_FLAGS) -DSQLITE_ENABLE_JSON1 -o $@ \
		$(TOP)/src/shell.c $(TOP)/ext/misc/json1.c libsqlite3.la \
		$(LIBREADLINE) $(TLIBS) -rpath "$(libdir)"

sqldiff$(TEXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS)

fuzzershell$(TEXE):	$(TOP)/tool/fuzzershell.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/fuzzershell.c sqlite3.c $(TLIBS)

!ENDIF
!ENDIF

# These are additional compiler options used for the shell executable.
#
!IFNDEF SHELL_COMPILE_OPTS
!IF $(DYNAMIC_SHELL)!=0
SHELL_COMPILE_OPTS = $(SHELL_CCONV_OPTS) -DSQLITE_API=__declspec(dllimport)
!ELSE
SHELL_COMPILE_OPTS = $(SHELL_CCONV_OPTS)
!ENDIF
!ENDIF

# This is the core library that the shell executable should depend on.
#
!IFNDEF SHELL_CORE_DEP
!IF $(DYNAMIC_SHELL)!=0
................................................................................

libsqlite3.lib:	$(LIBOBJ)
	$(LTLIB) $(LTLIBOPTS) /OUT:$@ $(LIBOBJ) $(TLIBS)

libtclsqlite3.lib:	tclsqlite.lo libsqlite3.lib
	$(LTLIB) $(LTLIBOPTS) $(LTLIBPATHS) /OUT:$@ tclsqlite.lo libsqlite3.lib $(LIBTCL:tcl=tclstub) $(TLIBS)

sqlite3.exe:	$(TOP)\src\shell.c $(SHELL_CORE_DEP) $(LIBRESOBJS) sqlite3.h
	$(LTLINK) $(SHELL_COMPILE_OPTS) $(READLINE_FLAGS) $(TOP)\src\shell.c \
		/link /pdb:sqlite3sh.pdb $(LTLINKOPTS) $(SHELL_LINK_OPTS) $(LTLIBPATHS) $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)

sqldiff.exe:	$(TOP)\tool\sqldiff.c sqlite3.c sqlite3.h
	$(LTLINK) $(NO_WARN) $(TOP)\tool\sqldiff.c sqlite3.c

fuzzershell.exe:	$(TOP)\tool\fuzzershell.c sqlite3.c sqlite3.h
	$(LTLINK) $(NO_WARN) $(TOP)\tool\fuzzershell.c sqlite3.c

!ENDIF
!ENDIF

# These are additional compiler options used for the shell executable.
#
!IFNDEF SHELL_COMPILE_OPTS
!IF $(DYNAMIC_SHELL)!=0
SHELL_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1 $(SHELL_CCONV_OPTS) -DSQLITE_API=__declspec(dllimport)
!ELSE
SHELL_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1 $(SHELL_CCONV_OPTS)
!ENDIF
!ENDIF

# This is the core library that the shell executable should depend on.
#
!IFNDEF SHELL_CORE_DEP
!IF $(DYNAMIC_SHELL)!=0
................................................................................

libsqlite3.lib:	$(LIBOBJ)
	$(LTLIB) $(LTLIBOPTS) /OUT:$@ $(LIBOBJ) $(TLIBS)

libtclsqlite3.lib:	tclsqlite.lo libsqlite3.lib
	$(LTLIB) $(LTLIBOPTS) $(LTLIBPATHS) /OUT:$@ tclsqlite.lo libsqlite3.lib $(LIBTCL:tcl=tclstub) $(TLIBS)

sqlite3.exe:	$(TOP)\src\shell.c $(TOP)\ext\misc\json1.c $(SHELL_CORE_DEP) $(LIBRESOBJS) sqlite3.h
	$(LTLINK) $(SHELL_COMPILE_OPTS) $(READLINE_FLAGS) $(TOP)\src\shell.c $(TOP)\ext\misc\json1.c \
		/link /pdb:sqlite3sh.pdb $(LTLINKOPTS) $(SHELL_LINK_OPTS) $(LTLIBPATHS) $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)

sqldiff.exe:	$(TOP)\tool\sqldiff.c sqlite3.c sqlite3.h
	$(LTLINK) $(NO_WARN) $(TOP)\tool\sqldiff.c sqlite3.c

fuzzershell.exe:	$(TOP)\tool\fuzzershell.c sqlite3.c sqlite3.h
	$(LTLINK) $(NO_WARN) $(TOP)\tool\fuzzershell.c sqlite3.c

**
** For the time being, all JSON is stored as pure text.  (We might add
** a JSONB type in the future which stores a binary encoding of JSON in
** a BLOB, but there is no support for JSONB in the current implementation.
** This implementation parses JSON text at 250 MB/s, so it is hard to see
** how JSONB might improve on that.)
*/

#include "sqlite3ext.h"

SQLITE_EXTENSION_INIT1
#include <assert.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdarg.h>

................................................................................
/* Bit values for the JsonNode.jnFlag field
*/
#define JNODE_RAW     0x01         /* Content is raw, not JSON encoded */
#define JNODE_ESCAPE  0x02         /* Content is text with \ escapes */
#define JNODE_REMOVE  0x04         /* Do not output */
#define JNODE_REPLACE 0x08         /* Replace with JsonNode.iVal */
#define JNODE_APPEND  0x10         /* More ARRAY/OBJECT entries at u.iAppend */



/* A single node of parsed JSON
*/
struct JsonNode {
  u8 eType;              /* One of the JSON_ type values */
  u8 jnFlags;            /* JNODE flags */
................................................................................
struct JsonParse {
  u32 nNode;         /* Number of slots of aNode[] used */
  u32 nAlloc;        /* Number of slots of aNode[] allocated */
  JsonNode *aNode;   /* Array of nodes containing the parse */
  const char *zJson; /* Original JSON string */
  u32 *aUp;          /* Index of parent of each node */
  u8 oom;            /* Set to true if out of memory */

};

/**************************************************************************
** Utility routines for dealing with JsonString objects
**************************************************************************/

/* Set the JsonString object to an empty string
................................................................................

/*
** Append a function parameter value to the JSON string under 
** construction.
*/
static void jsonAppendValue(
  JsonString *p,                 /* Append to this JSON string */
  sqlite3_value *pValue          /* Value to append */

){
  switch( sqlite3_value_type(pValue) ){
    case SQLITE_NULL: {
      jsonAppendRaw(p, "null", 4);
      break;
    }
    case SQLITE_INTEGER:
................................................................................
      u32 n = (u32)sqlite3_value_bytes(pValue);
      jsonAppendRaw(p, z, n);
      break;
    }
    case SQLITE_TEXT: {
      const char *z = (const char*)sqlite3_value_text(pValue);
      u32 n = (u32)sqlite3_value_bytes(pValue);



      jsonAppendString(p, z, n);

      break;
    }
    default: {
      if( p->bErr==0 ){
        sqlite3_result_error(p->pCtx, "JSON cannot hold BLOB values", -1);
        p->bErr = 1;
        jsonReset(p);
................................................................................
      u32 j = 1;
      jsonAppendChar(pOut, '[');
      for(;;){
        while( j<=pNode->n ){
          if( pNode[j].jnFlags & (JNODE_REMOVE|JNODE_REPLACE) ){
            if( pNode[j].jnFlags & JNODE_REPLACE ){
              jsonAppendSeparator(pOut);
              jsonAppendValue(pOut, aReplace[pNode[j].iVal]);

            }
          }else{
            jsonAppendSeparator(pOut);
            jsonRenderNode(&pNode[j], pOut, aReplace);
          }
          j += jsonNodeSize(&pNode[j]);
        }
................................................................................
      for(;;){
        while( j<=pNode->n ){
          if( (pNode[j+1].jnFlags & JNODE_REMOVE)==0 ){
            jsonAppendSeparator(pOut);
            jsonRenderNode(&pNode[j], pOut, aReplace);
            jsonAppendChar(pOut, ':');
            if( pNode[j+1].jnFlags & JNODE_REPLACE ){
              jsonAppendValue(pOut, aReplace[pNode[j+1].iVal]);

            }else{
              jsonRenderNode(&pNode[j+1], pOut, aReplace);
            }
          }
          j += 1 + jsonNodeSize(&pNode[j+1]);
        }
        if( (pNode->jnFlags & JNODE_APPEND)==0 ) break;
................................................................................
        j = 1;
      }
      jsonAppendChar(pOut, '}');
      break;
    }
  }
}















/*
** Make the JsonNode the return value of the function.
*/
static void jsonReturn(
  JsonNode *pNode,            /* Node to return */
  sqlite3_context *pCtx,      /* Return value for this function */
................................................................................
        zOut[j] = 0;
        sqlite3_result_text(pCtx, zOut, j, sqlite3_free);
      }
      break;
    }
    case JSON_ARRAY:
    case JSON_OBJECT: {
      JsonString s;
      jsonInit(&s, pCtx);
      jsonRenderNode(pNode, &s, aReplace);
      jsonResult(&s);
      break;
    }
  }
}

/*
** Create a new JsonNode instance based on the arguments and append that
................................................................................
        if( seenE ) return -1;
        seenDP = seenE = 1;
        c = pParse->zJson[j+1];
        if( c=='+' || c=='-' ){
          j++;
          c = pParse->zJson[j+1];
        }
        if( c<'0' || c>'0' ) return -1;
        continue;
      }
      break;
    }
    if( pParse->zJson[j-1]<'0' ) return -1;
    jsonParseAddNode(pParse, seenDP ? JSON_REAL : JSON_INT,
                        j - i, &pParse->zJson[i]);
................................................................................
  pParse->zJson = zJson;
  i = jsonParseValue(pParse, 0);
  if( pParse->oom ) i = -1;
  if( i>0 ){
    while( isspace(zJson[i]) ) i++;
    if( zJson[i] ) i = -1;
  }
  if( i<0 ){


    if( pParse->oom && pCtx!=0 ) sqlite3_result_error_nomem(pCtx);




    jsonParseReset(pParse);
    return 1;
  }
  return 0;
}

/* Mark node i of pParse as being a child of iParent.  Call recursively
................................................................................
    return SQLITE_NOMEM;
  }
  jsonParseFillInParentage(pParse, 0, 0);
  return SQLITE_OK;
}

/* forward declaration */
static JsonNode *jsonLookupAppend(JsonParse*,const char*,int*);

/*
** Search along zPath to find the node specified.  Return a pointer
** to that node, or NULL if zPath is malformed or if there is no such
** node.
**
** If pApnd!=0, then try to append new nodes to complete zPath if it is
** possible to do so and if no existing node corresponds to zPath.  If
** new nodes are appended *pApnd is set to 1.
*/
static JsonNode *jsonLookup(
  JsonParse *pParse,      /* The JSON to search */
  u32 iRoot,              /* Begin the search at this node */
  const char *zPath,      /* The path to search */
  int *pApnd              /* Append nodes to complete path if not NULL */

){
  u32 i, j, nKey;
  const char *zKey;
  JsonNode *pRoot = &pParse->aNode[iRoot];
  if( zPath[0]==0 ) return pRoot;
  if( zPath[0]=='.' ){
    if( pRoot->eType!=JSON_OBJECT ) return 0;
................................................................................
      nKey = i-1;
      if( zPath[i] ) i++;
    }else{
      zKey = zPath;
      for(i=0; zPath[i] && zPath[i]!='.' && zPath[i]!='['; i++){}
      nKey = i;
    }
    if( nKey==0 ) return 0;



    j = 1;
    for(;;){
      while( j<=pRoot->n ){
        if( pRoot[j].n==nKey+2
         && strncmp(&pRoot[j].u.zJContent[1],zKey,nKey)==0
        ){
          return jsonLookup(pParse, iRoot+j+1, &zPath[i], pApnd);
        }
        j++;
        j += jsonNodeSize(&pRoot[j]);
      }
      if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break;
      iRoot += pRoot->u.iAppend;
      pRoot = &pParse->aNode[iRoot];
................................................................................
    }
    if( pApnd ){
      u32 iStart, iLabel;
      JsonNode *pNode;
      iStart = jsonParseAddNode(pParse, JSON_OBJECT, 2, 0);
      iLabel = jsonParseAddNode(pParse, JSON_STRING, i, zPath);
      zPath += i;
      pNode = jsonLookupAppend(pParse, zPath, pApnd);
      if( pParse->oom ) return 0;
      if( pNode ){
        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
        pParse->aNode[iLabel].jnFlags |= JNODE_RAW;
      }
................................................................................
    if( pRoot->eType!=JSON_ARRAY ) return 0;
    i = 0;
    zPath++;
    while( isdigit(zPath[0]) ){
      i = i*10 + zPath[0] - '0';
      zPath++;
    }
    if( zPath[0]!=']' ) return 0;



    zPath++;
    j = 1;
    for(;;){
      while( j<=pRoot->n && (i>0 || (pRoot[j].jnFlags & JNODE_REMOVE)!=0) ){
        if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 ) i--;
        j += jsonNodeSize(&pRoot[j]);
      }
      if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break;
      iRoot += pRoot->u.iAppend;
      pRoot = &pParse->aNode[iRoot];
      j = 1;
    }
    if( j<=pRoot->n ){
      return jsonLookup(pParse, iRoot+j, zPath, pApnd);
    }
    if( i==0 && pApnd ){
      u32 iStart;
      JsonNode *pNode;
      iStart = jsonParseAddNode(pParse, JSON_ARRAY, 1, 0);
      pNode = jsonLookupAppend(pParse, zPath, pApnd);
      if( pParse->oom ) return 0;
      if( pNode ){
        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
      }
      return pNode;
    }


  }
  return 0;
}

/*
** Append content to pParse that will complete zPath.  Return a pointer
** to the inserted node, or return NULL if the append fails.
*/
static JsonNode *jsonLookupAppend(
  JsonParse *pParse,     /* Append content to the JSON parse */
  const char *zPath,     /* Description of content to append */
  int *pApnd             /* Set this flag to 1 */

){
  *pApnd = 1;
  if( zPath[0]==0 ){
    jsonParseAddNode(pParse, JSON_NULL, 0, 0);
    return pParse->oom ? 0 : &pParse->aNode[pParse->nNode-1];
  }
  if( zPath[0]=='.' ){
................................................................................
    jsonParseAddNode(pParse, JSON_OBJECT, 0, 0);
  }else if( strncmp(zPath,"[0]",3)==0 ){
    jsonParseAddNode(pParse, JSON_ARRAY, 0, 0);
  }else{
    return 0;
  }
  if( pParse->oom ) return 0;
  return jsonLookup(pParse, pParse->nNode-1, zPath, pApnd);
}




































































/*
** Report the wrong number of arguments for json_insert(), json_replace()
** or json_set().
*/
static void jsonWrongNumArgs(
  sqlite3_context *pCtx,
................................................................................
  const char *zFuncName
){
  char *zMsg = sqlite3_mprintf("json_%s() needs an odd number of arguments",
                               zFuncName);
  sqlite3_result_error(pCtx, zMsg, -1);
  sqlite3_free(zMsg);     
}


/****************************************************************************
** SQL functions used for testing and debugging
****************************************************************************/

#ifdef SQLITE_DEBUG
/*
................................................................................
static void jsonTest1Func(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;  /* The parse */
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  jsonReturn(x.aNode, ctx, 0);
  jsonParseReset(&x);
}

/*
** The json_nodecount(JSON) function returns the number of nodes in the
** input JSON string.
*/
................................................................................
  int i;
  JsonString jx;

  jsonInit(&jx, ctx);
  jsonAppendChar(&jx, '[');
  for(i=0; i<argc; i++){
    jsonAppendSeparator(&jx);
    jsonAppendValue(&jx, argv[i]);
  }
  jsonAppendChar(&jx, ']');
  jsonResult(&jx);
}


/*
................................................................................
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  sqlite3_int64 n = 0;
  u32 i;
  const char *zPath;




  if( argc==2 ){
    zPath = (const char*)sqlite3_value_text(argv[1]);
    if( zPath==0 ) return;
    if( zPath[0]!='$' ) return;
    zPath++;
  }else{
    zPath = 0;
  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0]))==0 ){
    if( x.nNode ){
      JsonNode *pNode = x.aNode;
      if( zPath ) pNode = jsonLookup(&x, 0, zPath, 0);
      if( pNode->eType==JSON_ARRAY ){
        assert( (pNode->jnFlags & JNODE_APPEND)==0 );
        for(i=1; i<=pNode->n; n++){
          i += jsonNodeSize(&pNode[i]);
        }
      }
    }

    jsonParseReset(&x);
  }
  if( !x.oom ) sqlite3_result_int64(ctx, n);
}

/*
** json_extract(JSON, PATH)
**
** Return the element described by PATH.  Return NULL if JSON is not
** valid JSON or if there is no PATH element or if PATH is malformed.



*/
static void jsonExtractFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  JsonNode *pNode;
  const char *zPath;
  assert( argc==2 );
  zPath = (const char*)sqlite3_value_text(argv[1]);

  if( zPath==0 ) return;
  if( zPath[0]!='$' ) return;
  zPath++;
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;




  pNode = jsonLookup(&x, 0, zPath, 0);



  if( pNode ){





    jsonReturn(pNode, ctx, 0);
  }






  jsonParseReset(&x);
}

/*
** Implementation of the json_object(NAME,VALUE,...) function.  Return a JSON
** object that contains all name/value given in arguments.  Or if any name
** is not a string or if any value is a BLOB, throw an error.
................................................................................
      return;
    }
    jsonAppendSeparator(&jx);
    z = (const char*)sqlite3_value_text(argv[i]);
    n = (u32)sqlite3_value_bytes(argv[i]);
    jsonAppendString(&jx, z, n);
    jsonAppendChar(&jx, ':');
    jsonAppendValue(&jx, argv[i+1]);
  }
  jsonAppendChar(&jx, '}');
  jsonResult(&jx);
}


/*
** json_remove(JSON, PATH, ...)
**
** Remove the named elements from JSON and return the result.  Ill-formed
** PATH arguments are silently ignored.  If JSON is ill-formed, then NULL
** is returned.
*/
static void jsonRemoveFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  u32 i;

  if( argc<1 ) return;
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i++){
      zPath = (const char*)sqlite3_value_text(argv[i]);
      if( zPath==0 ) continue;
      if( zPath[0]!='$' ) continue;
      pNode = jsonLookup(&x, 0, &zPath[1], 0);
      if( pNode ) pNode->jnFlags |= JNODE_REMOVE;
    }
    if( (x.aNode[0].jnFlags & JNODE_REMOVE)==0 ){
      jsonReturn(x.aNode, ctx, 0);
    }
  }

  jsonParseReset(&x);
}

/*
** json_replace(JSON, PATH, VALUE, ...)
**
** Replace the value at PATH with VALUE.  If PATH does not already exist,
** this routine is a no-op.  If JSON is ill-formed, return NULL.
*/
static void jsonReplaceFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  if( (argc&1)==0 ) {
    jsonWrongNumArgs(ctx, "replace");
    return;
  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i+=2){
      zPath = (const char*)sqlite3_value_text(argv[i]);
      if( zPath==0 ) continue;
      if( zPath[0]!='$' ) continue;
      pNode = jsonLookup(&x, 0, &zPath[1], 0);
      if( pNode ){
        pNode->jnFlags |= JNODE_REPLACE;

        pNode->iVal = i+1;
      }
    }
    if( x.aNode[0].jnFlags & JNODE_REPLACE ){
      sqlite3_result_value(ctx, argv[x.aNode[0].iVal]);
    }else{
      jsonReturn(x.aNode, ctx, argv);
    }
  }

  jsonParseReset(&x);
}

/*
** json_set(JSON, PATH, VALUE, ...)
**
** Set the value at PATH to VALUE.  Create the PATH if it does not already
** exist.  Overwrite existing values that do exist.
** If JSON is ill-formed, return NULL.
**
** json_insert(JSON, PATH, VALUE, ...)
**
** Create PATH and initialize it to VALUE.  If PATH already exists, this
** routine is a no-op.  If JSON is ill-formed, return NULL.
*/
static void jsonSetFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  if( (argc&1)==0 ) {
    jsonWrongNumArgs(ctx, bIsSet ? "set" : "insert");
    return;
  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i+=2){

      zPath = (const char*)sqlite3_value_text(argv[i]);
      if( zPath==0 ) continue;
      if( zPath[0]!='$' ) continue;
      bApnd = 0;
      pNode = jsonLookup(&x, 0, &zPath[1], &bApnd);
      if( x.oom ){
        sqlite3_result_error_nomem(ctx);
        goto jsonSetDone;


      }else if( pNode && (bApnd || bIsSet) ){

        pNode->jnFlags |= JNODE_REPLACE;
        pNode->iVal = i+1;
      }
    }
    if( x.aNode[0].jnFlags & JNODE_REPLACE ){
      sqlite3_result_value(ctx, argv[x.aNode[0].iVal]);
    }else{
      jsonReturn(x.aNode, ctx, argv);
    }
  }
jsonSetDone:
  jsonParseReset(&x);
}

/*
** json_type(JSON)
** json_type(JSON, PATH)
**
** Return the top-level "type" of a JSON string.  Return NULL if the
** input is not a well-formed JSON string.
*/
static void jsonTypeFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  const char *zPath;




  if( argc==2 ){
    zPath = (const char*)sqlite3_value_text(argv[1]);
    if( zPath==0 ) return;
    if( zPath[0]!='$' ) return;
    zPath++;

  }else{
    zPath = 0;

  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    JsonNode *pNode = x.aNode;
    if( zPath ) pNode = jsonLookup(&x, 0, zPath, 0);
    if( pNode ){
      sqlite3_result_text(ctx, jsonType[pNode->eType], -1, SQLITE_STATIC);
    }
  }
  jsonParseReset(&x);
}

/*
** json_valid(JSON)
**

** Return 1 if JSON is a valid JSON string.  Return 0 otherwise.
*/
static void jsonValidFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  int rc = 0;

  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0]))==0 
   && x.nNode>0
  ){
    rc = 1;
  }
  jsonParseReset(&x);
  sqlite3_result_int(ctx, rc);
}


/****************************************************************************
** The json_each virtual table
****************************************************************************/
typedef struct JsonEachCursor JsonEachCursor;
struct JsonEachCursor {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  u32 iRowid;                /* The rowid */
................................................................................
  UNUSED_PARAM(argc);
  jsonEachCursorReset(p);
  if( idxNum==0 ) return SQLITE_OK;
  z = (const char*)sqlite3_value_text(argv[0]);
  if( z==0 ) return SQLITE_OK;
  if( idxNum&2 ){
    zPath = (const char*)sqlite3_value_text(argv[1]);
    if( zPath==0 || zPath[0]!='$' ) return SQLITE_OK;





  }
  n = sqlite3_value_bytes(argv[0]);
  p->zJson = sqlite3_malloc64( n+1 );
  if( p->zJson==0 ) return SQLITE_NOMEM;
  memcpy(p->zJson, z, (size_t)n+1);
  if( jsonParse(&p->sParse, 0, p->zJson) 








   || (p->bRecursive && jsonParseFindParents(&p->sParse))
  ){
    jsonEachCursorReset(p);

  }else{
    JsonNode *pNode;
    if( idxNum==3 ){

      p->bRecursive = 0;
      n = sqlite3_value_bytes(argv[1]);
      p->zPath = sqlite3_malloc64( n+1 );
      if( p->zPath==0 ) return SQLITE_NOMEM;
      memcpy(p->zPath, zPath, (size_t)n+1);
      pNode = jsonLookup(&p->sParse, 0, p->zPath+1, 0);
      if( pNode==0 ){


        jsonEachCursorReset(p);


        return SQLITE_OK;
      }
    }else{
      pNode = p->sParse.aNode;
    }
    p->i = (int)(pNode - p->sParse.aNode);
    p->eType = pNode->eType;
................................................................................
  0,                         /* xRollback */
  0,                         /* xFindMethod */
  0,                         /* xRename */
  0,                         /* xSavepoint */
  0,                         /* xRelease */
  0                          /* xRollbackTo */
};


/****************************************************************************
** The following routine is the only publically visible identifier in this
** file.  Call the following routine in order to register the various SQL
** functions and the virtual table implemented by this file.
****************************************************************************/

................................................................................
     int nArg;
     int flag;
     void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
  } aFunc[] = {
    { "json_array",          -1, 0,   jsonArrayFunc         },
    { "json_array_length",    1, 0,   jsonArrayLengthFunc   },
    { "json_array_length",    2, 0,   jsonArrayLengthFunc   },
    { "json_extract",         2, 0,   jsonExtractFunc       },
    { "json_insert",         -1, 0,   jsonSetFunc           },
    { "json_object",         -1, 0,   jsonObjectFunc        },
    { "json_remove",         -1, 0,   jsonRemoveFunc        },
    { "json_replace",        -1, 0,   jsonReplaceFunc       },
    { "json_set",            -1, 1,   jsonSetFunc           },
    { "json_type",            1, 0,   jsonTypeFunc          },
    { "json_type",            2, 0,   jsonTypeFunc          },
................................................................................
#if SQLITE_DEBUG
    /* DEBUG and TESTING functions */
    { "json_parse",           1, 0,   jsonParseFunc         },
    { "json_test1",           1, 0,   jsonTest1Func         },
    { "json_nodecount",       1, 0,   jsonNodeCountFunc     },
#endif
  };

  static const struct {
     const char *zName;
     sqlite3_module *pModule;
  } aMod[] = {
    { "json_each",            &jsonEachModule               },
    { "json_tree",            &jsonTreeModule               },
  };

  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){
    rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg,
                                 SQLITE_UTF8 | SQLITE_DETERMINISTIC, 
                                 (void*)&aFunc[i].flag,
                                 aFunc[i].xFunc, 0, 0);
  }

  for(i=0; i<sizeof(aMod)/sizeof(aMod[0]) && rc==SQLITE_OK; i++){
    rc = sqlite3_create_module(db, aMod[i].zName, aMod[i].pModule, 0);
  }

  return rc;
}

**
** For the time being, all JSON is stored as pure text.  (We might add
** a JSONB type in the future which stores a binary encoding of JSON in
** a BLOB, but there is no support for JSONB in the current implementation.
** This implementation parses JSON text at 250 MB/s, so it is hard to see
** how JSONB might improve on that.)
*/
#if !defined(_SQLITEINT_H_)
#include "sqlite3ext.h"
#endif
SQLITE_EXTENSION_INIT1
#include <assert.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdarg.h>

................................................................................
/* Bit values for the JsonNode.jnFlag field
*/
#define JNODE_RAW     0x01         /* Content is raw, not JSON encoded */
#define JNODE_ESCAPE  0x02         /* Content is text with \ escapes */
#define JNODE_REMOVE  0x04         /* Do not output */
#define JNODE_REPLACE 0x08         /* Replace with JsonNode.iVal */
#define JNODE_APPEND  0x10         /* More ARRAY/OBJECT entries at u.iAppend */
#define JNODE_JSON    0x20         /* Treat REPLACE as JSON text */


/* A single node of parsed JSON
*/
struct JsonNode {
  u8 eType;              /* One of the JSON_ type values */
  u8 jnFlags;            /* JNODE flags */
................................................................................
struct JsonParse {
  u32 nNode;         /* Number of slots of aNode[] used */
  u32 nAlloc;        /* Number of slots of aNode[] allocated */
  JsonNode *aNode;   /* Array of nodes containing the parse */
  const char *zJson; /* Original JSON string */
  u32 *aUp;          /* Index of parent of each node */
  u8 oom;            /* Set to true if out of memory */
  u8 nErr;           /* Number of errors seen */
};

/**************************************************************************
** Utility routines for dealing with JsonString objects
**************************************************************************/

/* Set the JsonString object to an empty string
................................................................................

/*
** Append a function parameter value to the JSON string under 
** construction.
*/
static void jsonAppendValue(
  JsonString *p,                 /* Append to this JSON string */
  sqlite3_value *pValue,         /* Value to append */
  u8 textIsJson                  /* Try to treat text values as JSON */
){
  switch( sqlite3_value_type(pValue) ){
    case SQLITE_NULL: {
      jsonAppendRaw(p, "null", 4);
      break;
    }
    case SQLITE_INTEGER:
................................................................................
      u32 n = (u32)sqlite3_value_bytes(pValue);
      jsonAppendRaw(p, z, n);
      break;
    }
    case SQLITE_TEXT: {
      const char *z = (const char*)sqlite3_value_text(pValue);
      u32 n = (u32)sqlite3_value_bytes(pValue);
      if( textIsJson ){
        jsonAppendRaw(p, z, n);
      }else{
        jsonAppendString(p, z, n);
      }
      break;
    }
    default: {
      if( p->bErr==0 ){
        sqlite3_result_error(p->pCtx, "JSON cannot hold BLOB values", -1);
        p->bErr = 1;
        jsonReset(p);
................................................................................
      u32 j = 1;
      jsonAppendChar(pOut, '[');
      for(;;){
        while( j<=pNode->n ){
          if( pNode[j].jnFlags & (JNODE_REMOVE|JNODE_REPLACE) ){
            if( pNode[j].jnFlags & JNODE_REPLACE ){
              jsonAppendSeparator(pOut);
              jsonAppendValue(pOut, aReplace[pNode[j].iVal],
                              (pNode[j].jnFlags & JNODE_JSON)!=0);
            }
          }else{
            jsonAppendSeparator(pOut);
            jsonRenderNode(&pNode[j], pOut, aReplace);
          }
          j += jsonNodeSize(&pNode[j]);
        }
................................................................................
      for(;;){
        while( j<=pNode->n ){
          if( (pNode[j+1].jnFlags & JNODE_REMOVE)==0 ){
            jsonAppendSeparator(pOut);
            jsonRenderNode(&pNode[j], pOut, aReplace);
            jsonAppendChar(pOut, ':');
            if( pNode[j+1].jnFlags & JNODE_REPLACE ){
              jsonAppendValue(pOut, aReplace[pNode[j+1].iVal],
                              (pNode[j+1].jnFlags & JNODE_JSON)!=0);
            }else{
              jsonRenderNode(&pNode[j+1], pOut, aReplace);
            }
          }
          j += 1 + jsonNodeSize(&pNode[j+1]);
        }
        if( (pNode->jnFlags & JNODE_APPEND)==0 ) break;
................................................................................
        j = 1;
      }
      jsonAppendChar(pOut, '}');
      break;
    }
  }
}

/*
** Return a JsonNode and all its descendents as a JSON string.
*/
static void jsonReturnJson(
  JsonNode *pNode,            /* Node to return */
  sqlite3_context *pCtx,      /* Return value for this function */
  sqlite3_value **aReplace    /* Array of replacement values */
){
  JsonString s;
  jsonInit(&s, pCtx);
  jsonRenderNode(pNode, &s, aReplace);
  jsonResult(&s);
}

/*
** Make the JsonNode the return value of the function.
*/
static void jsonReturn(
  JsonNode *pNode,            /* Node to return */
  sqlite3_context *pCtx,      /* Return value for this function */
................................................................................
        zOut[j] = 0;
        sqlite3_result_text(pCtx, zOut, j, sqlite3_free);
      }
      break;
    }
    case JSON_ARRAY:
    case JSON_OBJECT: {
      jsonReturnJson(pNode, pCtx, aReplace);



      break;
    }
  }
}

/*
** Create a new JsonNode instance based on the arguments and append that
................................................................................
        if( seenE ) return -1;
        seenDP = seenE = 1;
        c = pParse->zJson[j+1];
        if( c=='+' || c=='-' ){
          j++;
          c = pParse->zJson[j+1];
        }
        if( c<'0' || c>'9' ) return -1;
        continue;
      }
      break;
    }
    if( pParse->zJson[j-1]<'0' ) return -1;
    jsonParseAddNode(pParse, seenDP ? JSON_REAL : JSON_INT,
                        j - i, &pParse->zJson[i]);
................................................................................
  pParse->zJson = zJson;
  i = jsonParseValue(pParse, 0);
  if( pParse->oom ) i = -1;
  if( i>0 ){
    while( isspace(zJson[i]) ) i++;
    if( zJson[i] ) i = -1;
  }
  if( i<=0 ){
    if( pCtx!=0 ){
      if( pParse->oom ){
        sqlite3_result_error_nomem(pCtx);
      }else{
        sqlite3_result_error(pCtx, "malformed JSON", -1);
      }
    }
    jsonParseReset(pParse);
    return 1;
  }
  return 0;
}

/* Mark node i of pParse as being a child of iParent.  Call recursively
................................................................................
    return SQLITE_NOMEM;
  }
  jsonParseFillInParentage(pParse, 0, 0);
  return SQLITE_OK;
}

/* forward declaration */
static JsonNode *jsonLookupAppend(JsonParse*,const char*,int*,const char**);

/*
** Search along zPath to find the node specified.  Return a pointer
** to that node, or NULL if zPath is malformed or if there is no such
** node.
**
** If pApnd!=0, then try to append new nodes to complete zPath if it is
** possible to do so and if no existing node corresponds to zPath.  If
** new nodes are appended *pApnd is set to 1.
*/
static JsonNode *jsonLookupStep(
  JsonParse *pParse,      /* The JSON to search */
  u32 iRoot,              /* Begin the search at this node */
  const char *zPath,      /* The path to search */
  int *pApnd,             /* Append nodes to complete path if not NULL */
  const char **pzErr      /* Make *pzErr point to any syntax error in zPath */
){
  u32 i, j, nKey;
  const char *zKey;
  JsonNode *pRoot = &pParse->aNode[iRoot];
  if( zPath[0]==0 ) return pRoot;
  if( zPath[0]=='.' ){
    if( pRoot->eType!=JSON_OBJECT ) return 0;
................................................................................
      nKey = i-1;
      if( zPath[i] ) i++;
    }else{
      zKey = zPath;
      for(i=0; zPath[i] && zPath[i]!='.' && zPath[i]!='['; i++){}
      nKey = i;
    }
    if( nKey==0 ){
      *pzErr = zPath;
      return 0;
    }
    j = 1;
    for(;;){
      while( j<=pRoot->n ){
        if( pRoot[j].n==nKey+2
         && strncmp(&pRoot[j].u.zJContent[1],zKey,nKey)==0
        ){
          return jsonLookupStep(pParse, iRoot+j+1, &zPath[i], pApnd, pzErr);
        }
        j++;
        j += jsonNodeSize(&pRoot[j]);
      }
      if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break;
      iRoot += pRoot->u.iAppend;
      pRoot = &pParse->aNode[iRoot];
................................................................................
    }
    if( pApnd ){
      u32 iStart, iLabel;
      JsonNode *pNode;
      iStart = jsonParseAddNode(pParse, JSON_OBJECT, 2, 0);
      iLabel = jsonParseAddNode(pParse, JSON_STRING, i, zPath);
      zPath += i;
      pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr);
      if( pParse->oom ) return 0;
      if( pNode ){
        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
        pParse->aNode[iLabel].jnFlags |= JNODE_RAW;
      }
................................................................................
    if( pRoot->eType!=JSON_ARRAY ) return 0;
    i = 0;
    zPath++;
    while( isdigit(zPath[0]) ){
      i = i*10 + zPath[0] - '0';
      zPath++;
    }
    if( zPath[0]!=']' ){
      *pzErr = zPath;
      return 0;
    }
    zPath++;
    j = 1;
    for(;;){
      while( j<=pRoot->n && (i>0 || (pRoot[j].jnFlags & JNODE_REMOVE)!=0) ){
        if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 ) i--;
        j += jsonNodeSize(&pRoot[j]);
      }
      if( (pRoot->jnFlags & JNODE_APPEND)==0 ) break;
      iRoot += pRoot->u.iAppend;
      pRoot = &pParse->aNode[iRoot];
      j = 1;
    }
    if( j<=pRoot->n ){
      return jsonLookupStep(pParse, iRoot+j, zPath, pApnd, pzErr);
    }
    if( i==0 && pApnd ){
      u32 iStart;
      JsonNode *pNode;
      iStart = jsonParseAddNode(pParse, JSON_ARRAY, 1, 0);
      pNode = jsonLookupAppend(pParse, zPath, pApnd, pzErr);
      if( pParse->oom ) return 0;
      if( pNode ){
        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
      }
      return pNode;
    }
  }else if( zPath[0]!=0 ){
    *pzErr = zPath;
  }
  return 0;
}

/*
** Append content to pParse that will complete zPath.  Return a pointer
** to the inserted node, or return NULL if the append fails.
*/
static JsonNode *jsonLookupAppend(
  JsonParse *pParse,     /* Append content to the JSON parse */
  const char *zPath,     /* Description of content to append */
  int *pApnd,            /* Set this flag to 1 */
  const char **pzErr     /* Make this point to any syntax error */
){
  *pApnd = 1;
  if( zPath[0]==0 ){
    jsonParseAddNode(pParse, JSON_NULL, 0, 0);
    return pParse->oom ? 0 : &pParse->aNode[pParse->nNode-1];
  }
  if( zPath[0]=='.' ){
................................................................................
    jsonParseAddNode(pParse, JSON_OBJECT, 0, 0);
  }else if( strncmp(zPath,"[0]",3)==0 ){
    jsonParseAddNode(pParse, JSON_ARRAY, 0, 0);
  }else{
    return 0;
  }
  if( pParse->oom ) return 0;
  return jsonLookupStep(pParse, pParse->nNode-1, zPath, pApnd, pzErr);
}

/*
** Return the text of a syntax error message on a JSON path.  Space is
** obtained from sqlite3_malloc().
*/
static char *jsonPathSyntaxError(const char *zErr){
  return sqlite3_mprintf("JSON path error near '%q'", zErr);
}

/*
** Do a node lookup using zPath.  Return a pointer to the node on success.
** Return NULL if not found or if there is an error.
**
** On an error, write an error message into pCtx and increment the
** pParse->nErr counter.
**
** If pApnd!=NULL then try to append missing nodes and set *pApnd = 1 if
** nodes are appended.
**
** If the path starts with $$ then set *pFlags to JNODE_REPLACE|JNODE_JSON
** as a single to the caller that the input text to be inserted should be 
** interpreted as JSON rather than as ordinary text.
*/
static JsonNode *jsonLookup(
  JsonParse *pParse,      /* The JSON to search */
  const char *zPath,      /* The path to search */
  int *pApnd,             /* Append nodes to complete path if not NULL */
  sqlite3_context *pCtx,  /* Report errors here, if not NULL */
  u8 *pFlags              /* Write JNODE_REPLACE or _REPLACE|_JSON here */
){
  const char *zErr = 0;
  JsonNode *pNode = 0;
  u8 fg = JNODE_REPLACE;

  if( zPath==0 ) return 0;
  if( zPath[0]!='$' ){
    zErr = zPath;
    goto lookup_err;
  }
  zPath++;
  if( zPath[0]=='$' ){
    if( pFlags==0 ){
      zErr = zPath;
      goto lookup_err;
    }
    zPath++;
    fg = JNODE_REPLACE|JNODE_JSON;
  }
  if( pFlags ) *pFlags = fg;
  pNode = jsonLookupStep(pParse, 0, zPath, pApnd, &zErr);
  return pNode;

lookup_err:
  pParse->nErr++;
  if( zErr!=0 && pCtx!=0 ){
    char *z = jsonPathSyntaxError(zErr);
    if( z ){
      sqlite3_result_error(pCtx, z, -1);
      sqlite3_free(z);
    }else{
      sqlite3_result_error_nomem(pCtx);
    }
  }
  if( pFlags ) *pFlags = fg;
  return 0;
}


/*
** Report the wrong number of arguments for json_insert(), json_replace()
** or json_set().
*/
static void jsonWrongNumArgs(
  sqlite3_context *pCtx,
................................................................................
  const char *zFuncName
){
  char *zMsg = sqlite3_mprintf("json_%s() needs an odd number of arguments",
                               zFuncName);
  sqlite3_result_error(pCtx, zMsg, -1);
  sqlite3_free(zMsg);     
}


/****************************************************************************
** SQL functions used for testing and debugging
****************************************************************************/

#ifdef SQLITE_DEBUG
/*
................................................................................
static void jsonTest1Func(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;  /* The parse */
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  jsonReturnJson(x.aNode, ctx, 0);
  jsonParseReset(&x);
}

/*
** The json_nodecount(JSON) function returns the number of nodes in the
** input JSON string.
*/
................................................................................
  int i;
  JsonString jx;

  jsonInit(&jx, ctx);
  jsonAppendChar(&jx, '[');
  for(i=0; i<argc; i++){
    jsonAppendSeparator(&jx);
    jsonAppendValue(&jx, argv[i], 0);
  }
  jsonAppendChar(&jx, ']');
  jsonResult(&jx);
}


/*
................................................................................
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  sqlite3_int64 n = 0;
  u32 i;


  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    JsonNode *pNode;
    if( argc==2 ){
      const char *zPath = (const char*)sqlite3_value_text(argv[1]);


      pNode = jsonLookup(&x, zPath, 0, ctx, 0);
    }else{
      pNode = x.aNode;
    }
    if( pNode==0 ){
      x.nErr = 1;


    }else if( pNode->eType==JSON_ARRAY ){
      assert( (pNode->jnFlags & JNODE_APPEND)==0 );
      for(i=1; i<=pNode->n; n++){
        i += jsonNodeSize(&pNode[i]);
      }
    }
  }
  if( x.nErr==0 ) sqlite3_result_int64(ctx, n);
  jsonParseReset(&x);
}



/*
** json_extract(JSON, PATH, ...)
**
** Return the element described by PATH.  Return NULL if there is no

** PATH element.  If there are multiple PATHs, then return a JSON array
** with the result from each path.  Throw an error if the JSON or any PATH
** is malformed.
*/
static void jsonExtractFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  JsonNode *pNode;
  const char *zPath;
  JsonString jx;
  int i;

  if( argc<2 ) return;


  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  jsonInit(&jx, ctx);
  jsonAppendChar(&jx, '[');
  for(i=1; i<argc; i++){
    zPath = (const char*)sqlite3_value_text(argv[i]);
    pNode = jsonLookup(&x, zPath, 0, ctx, 0);
    if( x.nErr ) break;
    if( argc>2 ){
      jsonAppendSeparator(&jx);
      if( pNode ){
        jsonRenderNode(pNode, &jx, 0);
      }else{
        jsonAppendRaw(&jx, "null", 4);
      }
    }else if( pNode ){
      jsonReturn(pNode, ctx, 0);
    }
  }
  if( argc>2 && i==argc ){
    jsonAppendChar(&jx, ']');
    jsonResult(&jx);
  }
  jsonReset(&jx);
  jsonParseReset(&x);
}

/*
** Implementation of the json_object(NAME,VALUE,...) function.  Return a JSON
** object that contains all name/value given in arguments.  Or if any name
** is not a string or if any value is a BLOB, throw an error.
................................................................................
      return;
    }
    jsonAppendSeparator(&jx);
    z = (const char*)sqlite3_value_text(argv[i]);
    n = (u32)sqlite3_value_bytes(argv[i]);
    jsonAppendString(&jx, z, n);
    jsonAppendChar(&jx, ':');
    jsonAppendValue(&jx, argv[i+1], 0);
  }
  jsonAppendChar(&jx, '}');
  jsonResult(&jx);
}


/*
** json_remove(JSON, PATH, ...)
**
** Remove the named elements from JSON and return the result.  malformed
** JSON or PATH arguments result in an error.

*/
static void jsonRemoveFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  u32 i;

  if( argc<1 ) return;
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i++){
      zPath = (const char*)sqlite3_value_text(argv[i]);
      if( zPath==0 ) goto remove_done;
      pNode = jsonLookup(&x, zPath, 0, ctx, 0);
      if( x.nErr ) goto remove_done;
      if( pNode ) pNode->jnFlags |= JNODE_REMOVE;
    }
    if( (x.aNode[0].jnFlags & JNODE_REMOVE)==0 ){
      jsonReturnJson(x.aNode, ctx, 0);
    }
  }
remove_done:
  jsonParseReset(&x);
}

/*
** json_replace(JSON, PATH, VALUE, ...)
**
** Replace the value at PATH with VALUE.  If PATH does not already exist,
** this routine is a no-op.  If JSON or PATH is malformed, throw an error.
*/
static void jsonReplaceFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  if( (argc&1)==0 ) {
    jsonWrongNumArgs(ctx, "replace");
    return;
  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i+=2){
      u8 jnFlags = JNODE_REPLACE;
      zPath = (const char*)sqlite3_value_text(argv[i]);
      pNode = jsonLookup(&x, zPath, 0, ctx, &jnFlags);
      if( x.nErr ) goto replace_err;
      if( pNode ){
        pNode->jnFlags &= ~JNODE_JSON;
        pNode->jnFlags |= jnFlags;
        pNode->iVal = i+1;
      }
    }
    if( x.aNode[0].jnFlags & JNODE_REPLACE ){
      sqlite3_result_value(ctx, argv[x.aNode[0].iVal]);
    }else{
      jsonReturnJson(x.aNode, ctx, argv);
    }
  }
replace_err:
  jsonParseReset(&x);
}

/*
** json_set(JSON, PATH, VALUE, ...)
**
** Set the value at PATH to VALUE.  Create the PATH if it does not already
** exist.  Overwrite existing values that do exist.
** If JSON or PATH is malformed, throw an error.
**
** json_insert(JSON, PATH, VALUE, ...)
**
** Create PATH and initialize it to VALUE.  If PATH already exists, this
** routine is a no-op.  If JSON or PATH is malformed, throw an error.
*/
static void jsonSetFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
................................................................................
  if( (argc&1)==0 ) {
    jsonWrongNumArgs(ctx, bIsSet ? "set" : "insert");
    return;
  }
  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    for(i=1; i<(u32)argc; i+=2){
      u8 jnFlags = JNODE_REPLACE;
      zPath = (const char*)sqlite3_value_text(argv[i]);


      bApnd = 0;
      pNode = jsonLookup(&x, zPath, &bApnd, ctx, &jnFlags);
      if( x.oom ){
        sqlite3_result_error_nomem(ctx);
        goto jsonSetDone;
      }else if( x.nErr ){
        goto jsonSetDone;
      }else if( pNode && (bApnd || bIsSet) ){
        pNode->jnFlags &= ~JNODE_JSON;
        pNode->jnFlags |= jnFlags;
        pNode->iVal = i+1;
      }
    }
    if( x.aNode[0].jnFlags & JNODE_REPLACE ){
      sqlite3_result_value(ctx, argv[x.aNode[0].iVal]);
    }else{
      jsonReturnJson(x.aNode, ctx, argv);
    }
  }
jsonSetDone:
  jsonParseReset(&x);
}

/*
** json_type(JSON)
** json_type(JSON, PATH)
**
** Return the top-level "type" of a JSON string.  Throw an error if
** either the JSON or PATH inputs are not well-formed.
*/
static void jsonTypeFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  const char *zPath;

  if( jsonParse(&x, ctx, (const char*)sqlite3_value_text(argv[0])) ) return;
  if( x.nNode ){
    JsonNode *pNode;
    if( argc==2 ){
      zPath = (const char*)sqlite3_value_text(argv[1]);



      pNode = jsonLookup(&x, zPath, 0, ctx, 0);
    }else{

      pNode = x.aNode;
    }




    if( pNode ){
      sqlite3_result_text(ctx, jsonType[pNode->eType], -1, SQLITE_STATIC);
    }
  }
  jsonParseReset(&x);
}

/*
** json_valid(JSON)
**
** Return 1 if JSON is a well-formed JSON string according to RFC-7159.
** Return 0 otherwise.
*/
static void jsonValidFunc(
  sqlite3_context *ctx,
  int argc,
  sqlite3_value **argv
){
  JsonParse x;          /* The parse */
  int rc = 0;

  if( jsonParse(&x, 0, (const char*)sqlite3_value_text(argv[0]))==0 
   && x.nNode>0
  ){
    rc = 1;
  }
  jsonParseReset(&x);
  sqlite3_result_int(ctx, rc);
}

#ifndef SQLITE_OMIT_VIRTUALTABLE
/****************************************************************************
** The json_each virtual table
****************************************************************************/
typedef struct JsonEachCursor JsonEachCursor;
struct JsonEachCursor {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  u32 iRowid;                /* The rowid */
................................................................................
  UNUSED_PARAM(argc);
  jsonEachCursorReset(p);
  if( idxNum==0 ) return SQLITE_OK;
  z = (const char*)sqlite3_value_text(argv[0]);
  if( z==0 ) return SQLITE_OK;
  if( idxNum&2 ){
    zPath = (const char*)sqlite3_value_text(argv[1]);
    if( zPath==0 ) return SQLITE_OK;
    if( zPath[0]!='$' ){
      sqlite3_free(cur->pVtab->zErrMsg);
      cur->pVtab->zErrMsg = jsonPathSyntaxError(zPath);
      return cur->pVtab->zErrMsg ? SQLITE_ERROR : SQLITE_NOMEM;
    }
  }
  n = sqlite3_value_bytes(argv[0]);
  p->zJson = sqlite3_malloc64( n+1 );
  if( p->zJson==0 ) return SQLITE_NOMEM;
  memcpy(p->zJson, z, (size_t)n+1);
  if( jsonParse(&p->sParse, 0, p->zJson) ){
    int rc = SQLITE_NOMEM;
    if( p->sParse.oom==0 ){
      sqlite3_free(cur->pVtab->zErrMsg);
      cur->pVtab->zErrMsg = sqlite3_mprintf("malformed JSON");
      if( cur->pVtab->zErrMsg ) rc = SQLITE_ERROR;
    }
    jsonEachCursorReset(p);
    return rc;
  }else if( p->bRecursive && jsonParseFindParents(&p->sParse) ){

    jsonEachCursorReset(p);
    return SQLITE_NOMEM;
  }else{
    JsonNode *pNode;
    if( idxNum==3 ){
      const char *zErr = 0;
      p->bRecursive = 0;
      n = sqlite3_value_bytes(argv[1]);
      p->zPath = sqlite3_malloc64( n+1 );
      if( p->zPath==0 ) return SQLITE_NOMEM;
      memcpy(p->zPath, zPath, (size_t)n+1);
      pNode = jsonLookupStep(&p->sParse, 0, p->zPath+1, 0, &zErr);
      if( p->sParse.nErr ){
        sqlite3_free(cur->pVtab->zErrMsg);
        cur->pVtab->zErrMsg = jsonPathSyntaxError(zErr);
        jsonEachCursorReset(p);
        return cur->pVtab->zErrMsg ? SQLITE_ERROR : SQLITE_NOMEM;
      }else if( pNode==0 ){
        return SQLITE_OK;
      }
    }else{
      pNode = p->sParse.aNode;
    }
    p->i = (int)(pNode - p->sParse.aNode);
    p->eType = pNode->eType;
................................................................................
  0,                         /* xRollback */
  0,                         /* xFindMethod */
  0,                         /* xRename */
  0,                         /* xSavepoint */
  0,                         /* xRelease */
  0                          /* xRollbackTo */
};
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/****************************************************************************
** The following routine is the only publically visible identifier in this
** file.  Call the following routine in order to register the various SQL
** functions and the virtual table implemented by this file.
****************************************************************************/

................................................................................
     int nArg;
     int flag;
     void (*xFunc)(sqlite3_context*,int,sqlite3_value**);
  } aFunc[] = {
    { "json_array",          -1, 0,   jsonArrayFunc         },
    { "json_array_length",    1, 0,   jsonArrayLengthFunc   },
    { "json_array_length",    2, 0,   jsonArrayLengthFunc   },
    { "json_extract",        -1, 0,   jsonExtractFunc       },
    { "json_insert",         -1, 0,   jsonSetFunc           },
    { "json_object",         -1, 0,   jsonObjectFunc        },
    { "json_remove",         -1, 0,   jsonRemoveFunc        },
    { "json_replace",        -1, 0,   jsonReplaceFunc       },
    { "json_set",            -1, 1,   jsonSetFunc           },
    { "json_type",            1, 0,   jsonTypeFunc          },
    { "json_type",            2, 0,   jsonTypeFunc          },
................................................................................
#if SQLITE_DEBUG
    /* DEBUG and TESTING functions */
    { "json_parse",           1, 0,   jsonParseFunc         },
    { "json_test1",           1, 0,   jsonTest1Func         },
    { "json_nodecount",       1, 0,   jsonNodeCountFunc     },
#endif
  };
#ifndef SQLITE_OMIT_VIRTUALTABLE
  static const struct {
     const char *zName;
     sqlite3_module *pModule;
  } aMod[] = {
    { "json_each",            &jsonEachModule               },
    { "json_tree",            &jsonTreeModule               },
  };
#endif
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){
    rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg,
                                 SQLITE_UTF8 | SQLITE_DETERMINISTIC, 
                                 (void*)&aFunc[i].flag,
                                 aFunc[i].xFunc, 0, 0);
  }
#ifndef SQLITE_OMIT_VIRTUALTABLE
  for(i=0; i<sizeof(aMod)/sizeof(aMod[0]) && rc==SQLITE_OK; i++){
    rc = sqlite3_create_module(db, aMod[i].zName, aMod[i].pModule, 0);
  }
#endif
  return rc;
}

        }
        zDelta++; lenDelta--;
        total += cnt;
        if( total>limit ){
          /* ERROR: copy exceeds output file size */
          return -1;
        }
        if( ofst+cnt > lenSrc ){
          /* ERROR: copy extends past end of input */
          return -1;
        }
        memcpy(zOut, &zSrc[ofst], cnt);
        zOut += cnt;
        break;
      }
................................................................................
      case ':': {
        zDelta++; lenDelta--;
        total += cnt;
        if( total>limit ){
          /* ERROR:  insert command gives an output larger than predicted */
          return -1;
        }
        if( cnt>lenDelta ){
          /* ERROR: insert count exceeds size of delta */
          return -1;
        }
        memcpy(zOut, zDelta, cnt);
        zOut += cnt;
        zDelta += cnt;
        lenDelta -= cnt;
................................................................................
        goto rbuTableType_end;
      }
    }
    *peType = RBU_PK_NONE;
  }

rbuTableType_end: {
    int i;
    for(i=0; i<sizeof(aStmt)/sizeof(aStmt[0]); i++){
      rbuFinalize(p, aStmt[i]);
    }
  }
}

/*
................................................................................
  RbuObjIter *pIter,
  const char *zMask
){
  char *zList = 0;
  if( p->rc==SQLITE_OK ){
    int i;

    if( strlen(zMask)!=pIter->nTblCol ){
      rbuBadControlError(p);
    }else{
      const char *zSep = "";
      for(i=0; i<pIter->nTblCol; i++){
        char c = zMask[pIter->aiSrcOrder[i]];
        if( c=='x' ){
          zList = rbuMPrintf(p, "%z%s\"%w\"=?%d", 
................................................................................
    rbuVfsCheckReservedLock,      /* xCheckReservedLock */
    rbuVfsFileControl,            /* xFileControl */
    rbuVfsSectorSize,             /* xSectorSize */
    rbuVfsDeviceCharacteristics,  /* xDeviceCharacteristics */
    rbuVfsShmMap,                 /* xShmMap */
    rbuVfsShmLock,                /* xShmLock */
    rbuVfsShmBarrier,             /* xShmBarrier */
    rbuVfsShmUnmap                /* xShmUnmap */

  };
  rbu_vfs *pRbuVfs = (rbu_vfs*)pVfs;
  sqlite3_vfs *pRealVfs = pRbuVfs->pRealVfs;
  rbu_file *pFd = (rbu_file *)pFile;
  int rc = SQLITE_OK;
  const char *zOpen = zName;

        }
        zDelta++; lenDelta--;
        total += cnt;
        if( total>limit ){
          /* ERROR: copy exceeds output file size */
          return -1;
        }
        if( (int)(ofst+cnt) > lenSrc ){
          /* ERROR: copy extends past end of input */
          return -1;
        }
        memcpy(zOut, &zSrc[ofst], cnt);
        zOut += cnt;
        break;
      }
................................................................................
      case ':': {
        zDelta++; lenDelta--;
        total += cnt;
        if( total>limit ){
          /* ERROR:  insert command gives an output larger than predicted */
          return -1;
        }
        if( (int)cnt>lenDelta ){
          /* ERROR: insert count exceeds size of delta */
          return -1;
        }
        memcpy(zOut, zDelta, cnt);
        zOut += cnt;
        zDelta += cnt;
        lenDelta -= cnt;
................................................................................
        goto rbuTableType_end;
      }
    }
    *peType = RBU_PK_NONE;
  }

rbuTableType_end: {
    unsigned int i;
    for(i=0; i<sizeof(aStmt)/sizeof(aStmt[0]); i++){
      rbuFinalize(p, aStmt[i]);
    }
  }
}

/*
................................................................................
  RbuObjIter *pIter,
  const char *zMask
){
  char *zList = 0;
  if( p->rc==SQLITE_OK ){
    int i;

    if( (int)strlen(zMask)!=pIter->nTblCol ){
      rbuBadControlError(p);
    }else{
      const char *zSep = "";
      for(i=0; i<pIter->nTblCol; i++){
        char c = zMask[pIter->aiSrcOrder[i]];
        if( c=='x' ){
          zList = rbuMPrintf(p, "%z%s\"%w\"=?%d", 
................................................................................
    rbuVfsCheckReservedLock,      /* xCheckReservedLock */
    rbuVfsFileControl,            /* xFileControl */
    rbuVfsSectorSize,             /* xSectorSize */
    rbuVfsDeviceCharacteristics,  /* xDeviceCharacteristics */
    rbuVfsShmMap,                 /* xShmMap */
    rbuVfsShmLock,                /* xShmLock */
    rbuVfsShmBarrier,             /* xShmBarrier */
    rbuVfsShmUnmap,               /* xShmUnmap */
    0, 0                          /* xFetch, xUnfetch */
  };
  rbu_vfs *pRbuVfs = (rbu_vfs*)pVfs;
  sqlite3_vfs *pRealVfs = pRbuVfs->pRealVfs;
  rbu_file *pFd = (rbu_file *)pFile;
  int rc = SQLITE_OK;
  const char *zOpen = zName;

#
all:	sqlite3.h libsqlite3.a sqlite3$(EXE)

libsqlite3.a:	$(LIBOBJ)
	$(AR) libsqlite3.a $(LIBOBJ)
	$(RANLIB) libsqlite3.a

sqlite3$(EXE):	$(TOP)/src/shell.c libsqlite3.a sqlite3.h
	$(TCCX) $(READLINE_FLAGS) -o sqlite3$(EXE)                  \
		$(TOP)/src/shell.c                                  \
		libsqlite3.a $(LIBREADLINE) $(TLIBS) $(THREADLIB)

sqldiff$(EXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(TCCX) -o sqldiff$(EXE) -DSQLITE_THREADSAFE=0 \
		$(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS) $(THREADLIB)

fuzzershell$(EXE):	$(TOP)/tool/fuzzershell.c sqlite3.c sqlite3.h

#
all:	sqlite3.h libsqlite3.a sqlite3$(EXE)

libsqlite3.a:	$(LIBOBJ)
	$(AR) libsqlite3.a $(LIBOBJ)
	$(RANLIB) libsqlite3.a

sqlite3$(EXE):	$(TOP)/src/shell.c libsqlite3.a sqlite3.h $(TOP)/ext/misc/json1.c
	$(TCCX) $(READLINE_FLAGS) -DSQLITE_ENABLE_JSON1 -o sqlite3$(EXE)  \
		$(TOP)/src/shell.c $(TOP)/ext/misc/json1.c                \
		libsqlite3.a $(LIBREADLINE) $(TLIBS) $(THREADLIB)

sqldiff$(EXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(TCCX) -o sqldiff$(EXE) -DSQLITE_THREADSAFE=0 \
		$(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS) $(THREADLIB)

fuzzershell$(EXE):	$(TOP)/tool/fuzzershell.c sqlite3.c sqlite3.h

  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    return 0;
  }

  p = sqlite3FindTable(pParse->db, zName, zDbase);
  if( p==0 ){
    const char *zMsg = isView ? "no such view" : "no such table";
#ifndef SQLITE_OMIT_VIRTUAL_TABLE
    /* If zName is the not the name of a table in the schema created using
    ** CREATE, then check to see if it is the name of an virtual table that
    ** can be an eponymous virtual table. */
    Module *pMod = (Module*)sqlite3HashFind(&pParse->db->aModule, zName);
    if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
      return pMod->pEpoTab;
    }

  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    return 0;
  }

  p = sqlite3FindTable(pParse->db, zName, zDbase);
  if( p==0 ){
    const char *zMsg = isView ? "no such view" : "no such table";
#ifndef SQLITE_OMIT_VIRTUALTABLE
    /* If zName is the not the name of a table in the schema created using
    ** CREATE, then check to see if it is the name of an virtual table that
    ** can be an eponymous virtual table. */
    Module *pMod = (Module*)sqlite3HashFind(&pParse->db->aModule, zName);
    if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
      return pMod->pEpoTab;
    }

    warnInmemoryDb = argc==1;
#else
    fprintf(stderr,"%s: Error: no database filename specified\n", Argv0);
    return 1;
#endif
  }
  data.out = stdout;








  /* Go ahead and open the database file if it already exists.  If the
  ** file does not exist, delay opening it.  This prevents empty database
  ** files from being created if a user mistypes the database name argument
  ** to the sqlite command-line tool.
  */
  if( access(data.zDbFilename, 0)==0 ){

    warnInmemoryDb = argc==1;
#else
    fprintf(stderr,"%s: Error: no database filename specified\n", Argv0);
    return 1;
#endif
  }
  data.out = stdout;

#ifdef SQLITE_ENABLE_JSON1
  {
    extern int sqlite3_json_init(sqlite3*);
    sqlite3_auto_extension((void(*)(void))sqlite3_json_init);
  }
#endif

  /* Go ahead and open the database file if it already exists.  If the
  ** file does not exist, delay opening it.  This prevents empty database
  ** files from being created if a user mistypes the database name argument
  ** to the sqlite command-line tool.
  */
  if( access(data.zDbFilename, 0)==0 ){

  u8 writeLock;              /* True if in a write transaction */
  u8 ckptLock;               /* True if holding a checkpoint lock */
  u8 readOnly;               /* WAL_RDWR, WAL_RDONLY, or WAL_SHM_RDONLY */
  u8 truncateOnCommit;       /* True to truncate WAL file on commit */
  u8 syncHeader;             /* Fsync the WAL header if true */
  u8 padToSectorBoundary;    /* Pad transactions out to the next sector */
  WalIndexHdr hdr;           /* Wal-index header for current transaction */

  const char *zWalName;      /* Name of WAL file */
  u32 nCkpt;                 /* Checkpoint sequence counter in the wal-header */
#ifdef SQLITE_DEBUG
  u8 lockError;              /* True if a locking error has occurred */
#endif
};

................................................................................
    ** that the log file may have been wrapped by a writer, or that frames
    ** that occur later in the log than pWal->hdr.mxFrame may have been
    ** copied into the database by a checkpointer. If either of these things
    ** happened, then reading the database with the current value of
    ** pWal->hdr.mxFrame risks reading a corrupted snapshot. So, retry
    ** instead.
    **
    ** This does not guarantee that the copy of the wal-index header is up to
    ** date before proceeding. That would not be possible without somehow
    ** blocking writers. It only guarantees that a dangerous checkpoint or 
    ** log-wrap (either of which would require an exclusive lock on
    ** WAL_READ_LOCK(mxI)) has not occurred since the snapshot was valid.














    */

    walShmBarrier(pWal);
    if( pInfo->aReadMark[mxI]!=mxReadMark
     || memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr))
    ){
      walUnlockShared(pWal, WAL_READ_LOCK(mxI));
      return WAL_RETRY;
    }else{
................................................................................
  Wal *pWal,                      /* WAL handle */
  Pgno pgno,                      /* Database page number to read data for */
  u32 *piRead                     /* OUT: Frame number (or zero) */
){
  u32 iRead = 0;                  /* If !=0, WAL frame to return data from */
  u32 iLast = pWal->hdr.mxFrame;  /* Last page in WAL for this reader */
  int iHash;                      /* Used to loop through N hash tables */


  /* This routine is only be called from within a read transaction. */
  assert( pWal->readLock>=0 || pWal->lockError );

  /* If the "last page" field of the wal-index header snapshot is 0, then
  ** no data will be read from the wal under any circumstances. Return early
  ** in this case as an optimization.  Likewise, if pWal->readLock==0, 
................................................................................
  **   (aPgno[iFrame]==pgno): 
  **     This condition filters out normal hash-table collisions.
  **
  **   (iFrame<=iLast): 
  **     This condition filters out entries that were added to the hash
  **     table after the current read-transaction had started.
  */

  for(iHash=walFramePage(iLast); iHash>=0 && iRead==0; iHash--){
    volatile ht_slot *aHash;      /* Pointer to hash table */
    volatile u32 *aPgno;          /* Pointer to array of page numbers */
    u32 iZero;                    /* Frame number corresponding to aPgno[0] */
    int iKey;                     /* Hash slot index */
    int nCollide;                 /* Number of hash collisions remaining */
    int rc;                       /* Error code */

................................................................................
    rc = walHashGet(pWal, iHash, &aHash, &aPgno, &iZero);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    nCollide = HASHTABLE_NSLOT;
    for(iKey=walHash(pgno); aHash[iKey]; iKey=walNextHash(iKey)){
      u32 iFrame = aHash[iKey] + iZero;
      if( iFrame<=iLast && aPgno[aHash[iKey]]==pgno ){
        assert( iFrame>iRead || CORRUPT_DB );
        iRead = iFrame;
      }
      if( (nCollide--)==0 ){
        return SQLITE_CORRUPT_BKPT;
      }
    }

  u8 writeLock;              /* True if in a write transaction */
  u8 ckptLock;               /* True if holding a checkpoint lock */
  u8 readOnly;               /* WAL_RDWR, WAL_RDONLY, or WAL_SHM_RDONLY */
  u8 truncateOnCommit;       /* True to truncate WAL file on commit */
  u8 syncHeader;             /* Fsync the WAL header if true */
  u8 padToSectorBoundary;    /* Pad transactions out to the next sector */
  WalIndexHdr hdr;           /* Wal-index header for current transaction */
  u32 minFrame;              /* Ignore wal frames before this one */
  const char *zWalName;      /* Name of WAL file */
  u32 nCkpt;                 /* Checkpoint sequence counter in the wal-header */
#ifdef SQLITE_DEBUG
  u8 lockError;              /* True if a locking error has occurred */
#endif
};

................................................................................
    ** that the log file may have been wrapped by a writer, or that frames
    ** that occur later in the log than pWal->hdr.mxFrame may have been
    ** copied into the database by a checkpointer. If either of these things
    ** happened, then reading the database with the current value of
    ** pWal->hdr.mxFrame risks reading a corrupted snapshot. So, retry
    ** instead.
    **
    ** Before checking that the live wal-index header has not changed
    ** since it was read, set Wal.minFrame to the first frame in the wal
    ** file that has not yet been checkpointed. This client will not need
    ** to read any frames earlier than minFrame from the wal file - they
    ** can be safely read directly from the database file.
    **
    ** Because a ShmBarrier() call is made between taking the copy of 
    ** nBackfill and checking that the wal-header in shared-memory still
    ** matches the one cached in pWal->hdr, it is guaranteed that the 
    ** checkpointer that set nBackfill was not working with a wal-index
    ** header newer than that cached in pWal->hdr. If it were, that could
    ** cause a problem. The checkpointer could omit to checkpoint
    ** a version of page X that lies before pWal->minFrame (call that version
    ** A) on the basis that there is a newer version (version B) of the same
    ** page later in the wal file. But if version B happens to like past
    ** frame pWal->hdr.mxFrame - then the client would incorrectly assume
    ** that it can read version A from the database file. However, since
    ** we can guarantee that the checkpointer that set nBackfill could not
    ** see any pages past pWal->hdr.mxFrame, this problem does not come up.
    */
    pWal->minFrame = pInfo->nBackfill+1;
    walShmBarrier(pWal);
    if( pInfo->aReadMark[mxI]!=mxReadMark
     || memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr))
    ){
      walUnlockShared(pWal, WAL_READ_LOCK(mxI));
      return WAL_RETRY;
    }else{
................................................................................
  Wal *pWal,                      /* WAL handle */
  Pgno pgno,                      /* Database page number to read data for */
  u32 *piRead                     /* OUT: Frame number (or zero) */
){
  u32 iRead = 0;                  /* If !=0, WAL frame to return data from */
  u32 iLast = pWal->hdr.mxFrame;  /* Last page in WAL for this reader */
  int iHash;                      /* Used to loop through N hash tables */
  int iMinHash;

  /* This routine is only be called from within a read transaction. */
  assert( pWal->readLock>=0 || pWal->lockError );

  /* If the "last page" field of the wal-index header snapshot is 0, then
  ** no data will be read from the wal under any circumstances. Return early
  ** in this case as an optimization.  Likewise, if pWal->readLock==0, 
................................................................................
  **   (aPgno[iFrame]==pgno): 
  **     This condition filters out normal hash-table collisions.
  **
  **   (iFrame<=iLast): 
  **     This condition filters out entries that were added to the hash
  **     table after the current read-transaction had started.
  */
  iMinHash = walFramePage(pWal->minFrame);
  for(iHash=walFramePage(iLast); iHash>=iMinHash && iRead==0; iHash--){
    volatile ht_slot *aHash;      /* Pointer to hash table */
    volatile u32 *aPgno;          /* Pointer to array of page numbers */
    u32 iZero;                    /* Frame number corresponding to aPgno[0] */
    int iKey;                     /* Hash slot index */
    int nCollide;                 /* Number of hash collisions remaining */
    int rc;                       /* Error code */

................................................................................
    rc = walHashGet(pWal, iHash, &aHash, &aPgno, &iZero);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    nCollide = HASHTABLE_NSLOT;
    for(iKey=walHash(pgno); aHash[iKey]; iKey=walNextHash(iKey)){
      u32 iFrame = aHash[iKey] + iZero;
      if( iFrame<=iLast && iFrame>=pWal->minFrame && aPgno[aHash[iKey]]==pgno ){
        assert( iFrame>iRead || CORRUPT_DB );
        iRead = iFrame;
      }
      if( (nCollide--)==0 ){
        return SQLITE_CORRUPT_BKPT;
      }
    }

} {1 {json_object() labels must be TEXT}}
do_catchsql_test json1-2.3 {
  SELECT json_object('a',1,'b');
} {1 {json_object() requires an even number of arguments}}
do_catchsql_test json1-2.4 {
  SELECT json_object('a',1,'b',x'abcd');
} {1 {JSON cannot hold BLOB values}}





































































































































































































finish_test

} {1 {json_object() labels must be TEXT}}
do_catchsql_test json1-2.3 {
  SELECT json_object('a',1,'b');
} {1 {json_object() requires an even number of arguments}}
do_catchsql_test json1-2.4 {
  SELECT json_object('a',1,'b',x'abcd');
} {1 {JSON cannot hold BLOB values}}

do_execsql_test json1-3.1 {
  SELECT json_replace('{"a":1,"b":2}','$.a','[3,4,5]');
} {{{"a":"[3,4,5]","b":2}}}
do_execsql_test json1-3.2 {
  SELECT json_replace('{"a":1,"b":2}','$$.a','[3,4,5]');
} {{{"a":[3,4,5],"b":2}}}
do_execsql_test json1-3.3 {
  SELECT json_type(json_set('{"a":1,"b":2}','$.b','{"x":3,"y":4}'),'$.b');
} {text}
do_execsql_test json1-3.4 {
  SELECT json_type(json_set('{"a":1,"b":2}','$$.b','{"x":3,"y":4}'),'$.b');
} {object}

# Per rfc7159, any JSON value is allowed at the top level, and whitespace
# is permitting before and/or after that value.
#
do_execsql_test json1-4.1 {
  CREATE TABLE j1(x);
  INSERT INTO j1(x)
   VALUES('true'),('false'),('null'),('123'),('-234'),('34.5e+6'),
         ('""'),('"\""'),('"\\"'),('"abcdefghijlmnopqrstuvwxyz"'),
         ('[]'),('{}'),('[true,false,null,123,-234,34.5e+6,{},[]]'),
         ('{"a":true,"b":{"c":false}}');
  SELECT * FROM j1 WHERE NOT json_valid(x);
} {}
do_execsql_test json1-4.2 {
  SELECT * FROM j1 WHERE NOT json_valid(char(0x20,0x09,0x0a,0x0d)||x);
} {}
do_execsql_test json1-4.3 {
  SELECT * FROM j1 WHERE NOT json_valid(x||char(0x20,0x09,0x0a,0x0d));
} {}

# But an empty string, or a string of pure whitespace is not valid JSON.
#
do_execsql_test json1-4.4 {
  SELECT json_valid(''), json_valid(char(0x20,0x09,0x0a,0x0d));
} {0 0}

# json_remove() and similar functions with no edit operations return their
# input unchanged.
#
do_execsql_test json1-4.5 {
  SELECT x FROM j1 WHERE json_remove(x)<>x;
} {}
do_execsql_test json1-4.6 {
  SELECT x FROM j1 WHERE json_replace(x)<>x;
} {}
do_execsql_test json1-4.7 {
  SELECT x FROM j1 WHERE json_set(x)<>x;
} {}
do_execsql_test json1-4.8 {
  SELECT x FROM j1 WHERE json_insert(x)<>x;
} {}

# json_extract(JSON,'$') will return objects and arrays without change.
#
do_execsql_test json-4.10 {
  SELECT count(*) FROM j1 WHERE json_type(x) IN ('object','array');
  SELECT x FROM j1
   WHERE json_extract(x,'$')<>x
     AND json_type(x) IN ('object','array');
} {4}

do_execsql_test json-5.1 {
  CREATE TABLE j2(id INTEGER PRIMARY KEY, json, src);
  INSERT INTO j2(id,json,src)
  VALUES(1,'{
    "firstName": "John",
    "lastName": "Smith",
    "isAlive": true,
    "age": 25,
    "address": {
      "streetAddress": "21 2nd Street",
      "city": "New York",
      "state": "NY",
      "postalCode": "10021-3100"
    },
    "phoneNumbers": [
      {
        "type": "home",
        "number": "212 555-1234"
      },
      {
        "type": "office",
        "number": "646 555-4567"
      }
    ],
    "children": [],
    "spouse": null
  }','https://en.wikipedia.org/wiki/JSON');
  INSERT INTO j2(id,json,src)
  VALUES(2, '{
	"id": "0001",
	"type": "donut",
	"name": "Cake",
	"ppu": 0.55,
	"batters":
		{
			"batter":
				[
					{ "id": "1001", "type": "Regular" },
					{ "id": "1002", "type": "Chocolate" },
					{ "id": "1003", "type": "Blueberry" },
					{ "id": "1004", "type": "Devil''s Food" }
				]
		},
	"topping":
		[
			{ "id": "5001", "type": "None" },
			{ "id": "5002", "type": "Glazed" },
			{ "id": "5005", "type": "Sugar" },
			{ "id": "5007", "type": "Powdered Sugar" },
			{ "id": "5006", "type": "Chocolate with Sprinkles" },
			{ "id": "5003", "type": "Chocolate" },
			{ "id": "5004", "type": "Maple" }
		]
   }','https://adobe.github.io/Spry/samples/data_region/JSONDataSetSample.html');
   INSERT INTO j2(id,json,src)
   VALUES(3,'[
	{
		"id": "0001",
		"type": "donut",
		"name": "Cake",
		"ppu": 0.55,
		"batters":
			{
				"batter":
					[
						{ "id": "1001", "type": "Regular" },
						{ "id": "1002", "type": "Chocolate" },
						{ "id": "1003", "type": "Blueberry" },
						{ "id": "1004", "type": "Devil''s Food" }
					]
			},
		"topping":
			[
				{ "id": "5001", "type": "None" },
				{ "id": "5002", "type": "Glazed" },
				{ "id": "5005", "type": "Sugar" },
				{ "id": "5007", "type": "Powdered Sugar" },
				{ "id": "5006", "type": "Chocolate with Sprinkles" },
				{ "id": "5003", "type": "Chocolate" },
				{ "id": "5004", "type": "Maple" }
			]
	},
	{
		"id": "0002",
		"type": "donut",
		"name": "Raised",
		"ppu": 0.55,
		"batters":
			{
				"batter":
					[
						{ "id": "1001", "type": "Regular" }
					]
			},
		"topping":
			[
				{ "id": "5001", "type": "None" },
				{ "id": "5002", "type": "Glazed" },
				{ "id": "5005", "type": "Sugar" },
				{ "id": "5003", "type": "Chocolate" },
				{ "id": "5004", "type": "Maple" }
			]
	},
	{
		"id": "0003",
		"type": "donut",
		"name": "Old Fashioned",
		"ppu": 0.55,
		"batters":
			{
				"batter":
					[
						{ "id": "1001", "type": "Regular" },
						{ "id": "1002", "type": "Chocolate" }
					]
			},
		"topping":
			[
				{ "id": "5001", "type": "None" },
				{ "id": "5002", "type": "Glazed" },
				{ "id": "5003", "type": "Chocolate" },
				{ "id": "5004", "type": "Maple" }
			]
	}
   ]','https://adobe.github.io/Spry/samples/data_region/JSONDataSetSample.html');
   SELECT count(*) FROM j2;
} {3}

do_execsql_test json-5.2 {
  SELECT id, json_valid(json), json_type(json), '|' FROM j2 ORDER BY id;
} {1 1 object | 2 1 object | 3 1 array |}

ifcapable !vtab {
  finish_test
  return
}

# fullkey is always the same as path+key (with appropriate formatting)
#
do_execsql_test json-5.3 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_tree(j2.json) AS jx
   WHERE fullkey!=(path || CASE WHEN typeof(key)=='integer' THEN '['||key||']'
                                ELSE '.'||key END);
} {}
do_execsql_test json-5.4 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_each(j2.json) AS jx
   WHERE fullkey!=(path || CASE WHEN typeof(key)=='integer' THEN '['||key||']'
                                ELSE '.'||key END);
} {}


# Verify that the json_each.json and json_tree.json output is always the
# same as input.
#
do_execsql_test json-5.5 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_each(j2.json) AS jx
   WHERE jx.json<>j2.json;
} {}
do_execsql_test json-5.6 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_tree(j2.json) AS jx
   WHERE jx.json<>j2.json;
} {}
do_execsql_test json-5.7 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_each(j2.json) AS jx
   WHERE jx.value<>jx.atom AND type NOT IN ('array','object');
} {}
do_execsql_test json-5.8 {
  SELECT j2.rowid, jx.rowid, fullkey, path, key
    FROM j2, json_tree(j2.json) AS jx
   WHERE jx.value<>jx.atom AND type NOT IN ('array','object');
} {}



finish_test

do_test rowid-2.8 {
  global x2rowid
  set sql "UPDATE t1 SET x=3 WHERE _rowid_==$x2rowid(3)"
  execsql $sql
  execsql {SELECT x FROM t1 ORDER BY x}
} {1 3 5 7 9}

if 0 {  # we can now....

# We cannot index by ROWID
#
do_test rowid-2.9 {
  set v [catch {execsql {CREATE INDEX idxt1 ON t1(rowid)}} msg]
  lappend v $msg
} {1 {table t1 has no column named rowid}}
do_test rowid-2.10 {

do_test rowid-2.8 {
  global x2rowid
  set sql "UPDATE t1 SET x=3 WHERE _rowid_==$x2rowid(3)"
  execsql $sql
  execsql {SELECT x FROM t1 ORDER BY x}
} {1 3 5 7 9}

if 0 {  # With the index-on-expressions enhancement, creating
        # an index on ROWID has become possible.
# We cannot index by ROWID
#
do_test rowid-2.9 {
  set v [catch {execsql {CREATE INDEX idxt1 ON t1(rowid)}} msg]
  lappend v $msg
} {1 {table t1 has no column named rowid}}
do_test rowid-2.10 {

} {}

db eval {SELECT test4('3.3.2')}

do_test 3.x {
  db2 close
} {}











































finish_test

} {}

db eval {SELECT test4('3.3.2')}

do_test 3.x {
  db2 close
} {}

#-------------------------------------------------------------------------
# Check that if a wal file has been partially checkpointed, no frames are
# read from the checkpointed part.
#
reset_db
do_execsql_test 4.1 {
  PRAGMA page_size = 1024;
  PRAGMA journal_mode = wal;
  CREATE TABLE t1(a, b);
  CREATE TABLE t2(a, b);
  PRAGMA wal_checkpoint = truncate;
} {wal 0 0 0}

do_test 4.2 {
  execsql { INSERT INTO t1 VALUES(1, 2) }
  file size test.db-wal
} [wal_file_size 1 1024]

do_test 4.3 {
  sqlite3 db2 test.db
  execsql { 
    BEGIN;
    INSERT INTO t2 VALUES(3, 4);
  }
  execsql { PRAGMA wal_checkpoint = passive } db2
} {0 1 1}

do_test 4.3 {
  execsql { COMMIT }
  db2 close
  hexio_write test.db-wal 0 [string repeat 00 2000]
  sqlite3 db2 test.db
} {}

do_test 4.4.1 { 
  catchsql { SELECT * FROM t1 } db2 
} {0 {1 2}}
do_test 4.4.2 { 
  catchsql { SELECT * FROM t2 } db2 
} {1 {database disk image is malformed}}


finish_test