Add missing intarray C file.

intarray.c

+/*
+** 2009 November 10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements a read-only VIRTUAL TABLE that contains the
+** content of a C-language array of integer values.  See the corresponding
+** header file for full details.
+*/
+#include <sqlite3.h>
+#include <string.h>
+#include <assert.h>
+
+/*
+** An sqlite3_intarray is an abstract type to stores an instance of
+** an integer array.
+*/
+typedef struct sqlite3_intarray sqlite3_intarray;
+
+/*
+** Definition of the sqlite3_intarray object.
+**
+** The internal representation of an intarray object is subject
+** to change, is not externally visible, and should be used by
+** the implementation of intarray only.  This object is opaque
+** to users.
+*/
+struct sqlite3_intarray {
+  int n;                    /* Number of elements in the array */
+  sqlite3_int64 *a;         /* Contents of the array */
+  void (*xFree)(void*);     /* Function used to free a[] */
+};
+
+/* Objects used internally by the virtual table implementation */
+typedef struct intarray_vtab intarray_vtab;
+typedef struct intarray_cursor intarray_cursor;
+
+/* A intarray table object */
+struct intarray_vtab {
+  sqlite3_vtab base;            /* Base class */
+  sqlite3_intarray *pContent;   /* Content of the integer array */
+};
+
+/* A intarray cursor object */
+struct intarray_cursor {
+  sqlite3_vtab_cursor base;    /* Base class */
+  int i;                       /* Current cursor position */
+};
+
+/*
+** Free an sqlite3_intarray object.
+*/
+static void intarrayFree(sqlite3_intarray *p){
+  if( p->xFree ){
+    p->xFree(p->a);
+  }
+  sqlite3_free(p);
+}
+
+/*
+** Table destructor for the intarray module.
+*/
+static int intarrayDestroy(sqlite3_vtab *p){
+  intarray_vtab *pVtab = (intarray_vtab*)p;
+  sqlite3_free(pVtab);
+  return 0;
+}
+
+/*
+** Table constructor for the intarray module.
+*/
+static int intarrayCreate(
+  sqlite3 *db,              /* Database where module is created */
+  void *pAux,               /* clientdata for the module */
+  int argc,                 /* Number of arguments */
+  const char *const*argv,   /* Value for all arguments */
+  sqlite3_vtab **ppVtab,    /* Write the new virtual table object here */
+  char **pzErr              /* Put error message text here */
+){
+  int rc = SQLITE_NOMEM;
+  intarray_vtab *pVtab = sqlite3_malloc(sizeof(intarray_vtab));
+
+  if( pVtab ){
+    memset(pVtab, 0, sizeof(intarray_vtab));
+    pVtab->pContent = (sqlite3_intarray*)pAux;
+    rc = sqlite3_declare_vtab(db, "CREATE TABLE x(value INTEGER PRIMARY KEY)");
+  }
+  *ppVtab = (sqlite3_vtab *)pVtab;
+  return rc;
+}
+
+/*
+** Open a new cursor on the intarray table.
+*/
+static int intarrayOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+  int rc = SQLITE_NOMEM;
+  intarray_cursor *pCur;
+  pCur = sqlite3_malloc(sizeof(intarray_cursor));
+  if( pCur ){
+    memset(pCur, 0, sizeof(intarray_cursor));
+    *ppCursor = (sqlite3_vtab_cursor *)pCur;
+    rc = SQLITE_OK;
+  }
+  return rc;
+}
+
+/*
+** Close a intarray table cursor.
+*/
+static int intarrayClose(sqlite3_vtab_cursor *cur){
+  intarray_cursor *pCur = (intarray_cursor *)cur;
+  sqlite3_free(pCur);
+  return SQLITE_OK;
+}
+
+/*
+** Retrieve a column of data.
+*/
+static int intarrayColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+  intarray_cursor *pCur = (intarray_cursor*)cur;
+  intarray_vtab *pVtab = (intarray_vtab*)cur->pVtab;
+  if( pCur->i>=0 && pCur->i<pVtab->pContent->n ){
+    sqlite3_result_int64(ctx, pVtab->pContent->a[pCur->i]);
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Retrieve the current rowid.
+*/
+static int intarrayRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  intarray_cursor *pCur = (intarray_cursor *)cur;
+  *pRowid = pCur->i;
+  return SQLITE_OK;
+}
+
+static int intarrayEof(sqlite3_vtab_cursor *cur){
+  intarray_cursor *pCur = (intarray_cursor *)cur;
+  intarray_vtab *pVtab = (intarray_vtab *)cur->pVtab;
+  return pCur->i>=pVtab->pContent->n;
+}
+
+/*
+** Advance the cursor to the next row.
+*/
+static int intarrayNext(sqlite3_vtab_cursor *cur){
+  intarray_cursor *pCur = (intarray_cursor *)cur;
+  pCur->i++;
+  return SQLITE_OK;
+}
+
+/*
+** Reset a intarray table cursor.
+*/
+static int intarrayFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  intarray_cursor *pCur = (intarray_cursor *)pVtabCursor;
+  pCur->i = 0;
+  return SQLITE_OK;
+}
+
+/*
+** Analyse the WHERE condition.
+*/
+static int intarrayBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+  return SQLITE_OK;
+}
+
+/*
+** A virtual table module that merely echos method calls into TCL
+** variables.
+*/
+static sqlite3_module intarrayModule = {
+  0,                           /* iVersion */
+  intarrayCreate,              /* xCreate - create a new virtual table */
+  intarrayCreate,              /* xConnect - connect to an existing vtab */
+  intarrayBestIndex,           /* xBestIndex - find the best query index */
+  intarrayDestroy,             /* xDisconnect - disconnect a vtab */
+  intarrayDestroy,             /* xDestroy - destroy a vtab */
+  intarrayOpen,                /* xOpen - open a cursor */
+  intarrayClose,               /* xClose - close a cursor */
+  intarrayFilter,              /* xFilter - configure scan constraints */
+  intarrayNext,                /* xNext - advance a cursor */
+  intarrayEof,                 /* xEof */
+  intarrayColumn,              /* xColumn - read data */
+  intarrayRowid,               /* xRowid - read data */
+  0,                           /* xUpdate */
+  0,                           /* xBegin */
+  0,                           /* xSync */
+  0,                           /* xCommit */
+  0,                           /* xRollback */
+  0,                           /* xFindMethod */
+  0,                           /* xRename */
+};
+
+/*
+** Invoke this routine to create a specific instance of an intarray object.
+** The new intarray object is returned by the 3rd parameter.
+**
+** Each intarray object corresponds to a virtual table in the TEMP table
+** with a name of zName.
+**
+** Destroy the intarray object by dropping the virtual table.  If not done
+** explicitly by the application, the virtual table will be dropped implicitly
+** by the system when the database connection is closed.
+*/
+int sqlite3_intarray_create(
+  sqlite3 *db,
+  const char *zName,
+  sqlite3_intarray **ppReturn
+){
+  int rc = SQLITE_OK;
+  sqlite3_intarray *p;
+
+  *ppReturn = p = sqlite3_malloc( sizeof(*p) );
+  if( p==0 ){
+    return SQLITE_NOMEM;
+  }
+  memset(p, 0, sizeof(*p));
+  rc = sqlite3_create_module_v2(db, zName, &intarrayModule, p,
+                                (void(*)(void*))intarrayFree);
+  if( rc==SQLITE_OK ){
+    char *zSql;
+    zSql = sqlite3_mprintf("CREATE VIRTUAL TABLE temp.%Q USING %Q",
+                           zName, zName);
+    rc = sqlite3_exec(db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
+  }
+  return rc;
+}
+
+/*
+** Bind a new array array of integers to a specific intarray object.
+**
+** The array of integers bound must be unchanged for the duration of
+** any query against the corresponding virtual table.  If the integer
+** array does change or is deallocated undefined behavior will result.
+*/
+int sqlite3_intarray_bind(
+  sqlite3_intarray *pIntArray,   /* The intarray object to bind to */
+  int nElements,                 /* Number of elements in the intarray */
+  sqlite3_int64 *aElements,      /* Content of the intarray */
+  void (*xFree)(void*)           /* How to dispose of the intarray when done */
+){
+  if( pIntArray->xFree ){
+    pIntArray->xFree(pIntArray->a);
+  }
+  pIntArray->n = nElements;
+  pIntArray->a = aElements;
+  pIntArray->xFree = xFree;
+  return SQLITE_OK;
+}