tclsqlite.c

sqlite-3.4.1,嵌入式数据库.是一个功能强大的开源数据库,给学习和研发以及小型公司的发展带来了全所未有的好处.

** copied from shell.c from '.import' command
*/
static char *local_getline(char *zPrompt, FILE *in){
  char *zLine;
  int nLine;
  int n;
  int eol;

  nLine = 100;
  zLine = malloc( nLine );
  if( zLine==0 ) return 0;
  n = 0;
  eol = 0;
  while( !eol ){
    if( n+100>nLine ){
      nLine = nLine*2 + 100;
      zLine = realloc(zLine, nLine);
      if( zLine==0 ) return 0;
    }
    if( fgets(&zLine[n], nLine - n, in)==0 ){
      if( n==0 ){
        free(zLine);
        return 0;
      }
      zLine[n] = 0;
      eol = 1;
      break;
    }
    while( zLine[n] ){ n++; }
    if( n>0 && zLine[n-1]=='\n' ){
      n--;
      zLine[n] = 0;
      eol = 1;
    }
  }
  zLine = realloc( zLine, n+1 );
  return zLine;
}

/*
** The "sqlite" command below creates a new Tcl command for each
** connection it opens to an SQLite database.  This routine is invoked
** whenever one of those connection-specific commands is executed
** in Tcl.  For example, if you run Tcl code like this:
**
**       sqlite3 db1  "my_database"
**       db1 close
**
** The first command opens a connection to the "my_database" database
** and calls that connection "db1".  The second command causes this
** subroutine to be invoked.
*/
static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){
  SqliteDb *pDb = (SqliteDb*)cd;
  int choice;
  int rc = TCL_OK;
  static const char *DB_strs[] = {
    "authorizer",         "busy",              "cache",
    "changes",            "close",             "collate",
    "collation_needed",   "commit_hook",       "complete",
    "copy",               "enable_load_extension","errorcode",
    "eval",               "exists",            "function",
    "incrblob",           "interrupt",         "last_insert_rowid",
    "nullvalue",          "onecolumn",         "profile",
    "progress",           "rekey",             "rollback_hook",
    "timeout",            "total_changes",     "trace",
    "transaction",        "update_hook",       "version",
    0                    
  };
  enum DB_enum {
    DB_AUTHORIZER,        DB_BUSY,             DB_CACHE,
    DB_CHANGES,           DB_CLOSE,            DB_COLLATE,
    DB_COLLATION_NEEDED,  DB_COMMIT_HOOK,      DB_COMPLETE,
    DB_COPY,              DB_ENABLE_LOAD_EXTENSION,DB_ERRORCODE,
    DB_EVAL,              DB_EXISTS,           DB_FUNCTION,
    DB_INCRBLOB,          DB_INTERRUPT,        DB_LAST_INSERT_ROWID,
    DB_NULLVALUE,         DB_ONECOLUMN,        DB_PROFILE,
    DB_PROGRESS,          DB_REKEY,            DB_ROLLBACK_HOOK,
    DB_TIMEOUT,           DB_TOTAL_CHANGES,    DB_TRACE,
    DB_TRANSACTION,       DB_UPDATE_HOOK,      DB_VERSION
  };
  /* don't leave trailing commas on DB_enum, it confuses the AIX xlc compiler */

  if( objc<2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "SUBCOMMAND ...");
    return TCL_ERROR;
  }
  if( Tcl_GetIndexFromObj(interp, objv[1], DB_strs, "option", 0, &choice) ){
    return TCL_ERROR;
  }

  switch( (enum DB_enum)choice ){

  /*    $db authorizer ?CALLBACK?
  **
  ** Invoke the given callback to authorize each SQL operation as it is
  ** compiled.  5 arguments are appended to the callback before it is
  ** invoked:
  **
  **   (1) The authorization type (ex: SQLITE_CREATE_TABLE, SQLITE_INSERT, ...)
  **   (2) First descriptive name (depends on authorization type)
  **   (3) Second descriptive name
  **   (4) Name of the database (ex: "main", "temp")
  **   (5) Name of trigger that is doing the access
  **
  ** The callback should return on of the following strings: SQLITE_OK,
  ** SQLITE_IGNORE, or SQLITE_DENY.  Any other return value is an error.
  **
  ** If this method is invoked with no arguments, the current authorization
  ** callback string is returned.
  */
  case DB_AUTHORIZER: {
#ifdef SQLITE_OMIT_AUTHORIZATION
    Tcl_AppendResult(interp, "authorization not available in this build", 0);
    return TCL_ERROR;
#else
    if( objc>3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "?CALLBACK?");
      return TCL_ERROR;
    }else if( objc==2 ){
      if( pDb->zAuth ){
        Tcl_AppendResult(interp, pDb->zAuth, 0);
      }
    }else{
      char *zAuth;
      int len;
      if( pDb->zAuth ){
        Tcl_Free(pDb->zAuth);
      }
      zAuth = Tcl_GetStringFromObj(objv[2], &len);
      if( zAuth && len>0 ){
        pDb->zAuth = Tcl_Alloc( len + 1 );
        memcpy(pDb->zAuth, zAuth, len+1);
      }else{
        pDb->zAuth = 0;
      }
      if( pDb->zAuth ){
        pDb->interp = interp;
        sqlite3_set_authorizer(pDb->db, auth_callback, pDb);
      }else{
        sqlite3_set_authorizer(pDb->db, 0, 0);
      }
    }
#endif
    break;
  }

  /*    $db busy ?CALLBACK?
  **
  ** Invoke the given callback if an SQL statement attempts to open
  ** a locked database file.
  */
  case DB_BUSY: {
    if( objc>3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "CALLBACK");
      return TCL_ERROR;
    }else if( objc==2 ){
      if( pDb->zBusy ){
        Tcl_AppendResult(interp, pDb->zBusy, 0);
      }
    }else{
      char *zBusy;
      int len;
      if( pDb->zBusy ){
        Tcl_Free(pDb->zBusy);
      }
      zBusy = Tcl_GetStringFromObj(objv[2], &len);
      if( zBusy && len>0 ){
        pDb->zBusy = Tcl_Alloc( len + 1 );
        memcpy(pDb->zBusy, zBusy, len+1);
      }else{
        pDb->zBusy = 0;
      }
      if( pDb->zBusy ){
        pDb->interp = interp;
        sqlite3_busy_handler(pDb->db, DbBusyHandler, pDb);
      }else{
        sqlite3_busy_handler(pDb->db, 0, 0);
      }
    }
    break;
  }

  /*     $db cache flush
  **     $db cache size n
  **
  ** Flush the prepared statement cache, or set the maximum number of
  ** cached statements.
  */
  case DB_CACHE: {
    char *subCmd;
    int n;

    if( objc<=2 ){
      Tcl_WrongNumArgs(interp, 1, objv, "cache option ?arg?");
      return TCL_ERROR;
    }
    subCmd = Tcl_GetStringFromObj( objv[2], 0 );
    if( *subCmd=='f' && strcmp(subCmd,"flush")==0 ){
      if( objc!=3 ){
        Tcl_WrongNumArgs(interp, 2, objv, "flush");
        return TCL_ERROR;
      }else{
        flushStmtCache( pDb );
      }
    }else if( *subCmd=='s' && strcmp(subCmd,"size")==0 ){
      if( objc!=4 ){
        Tcl_WrongNumArgs(interp, 2, objv, "size n");
        return TCL_ERROR;
      }else{
        if( TCL_ERROR==Tcl_GetIntFromObj(interp, objv[3], &n) ){
          Tcl_AppendResult( interp, "cannot convert \"", 
               Tcl_GetStringFromObj(objv[3],0), "\" to integer", 0);
          return TCL_ERROR;
        }else{
          if( n<0 ){
            flushStmtCache( pDb );
            n = 0;
          }else if( n>MAX_PREPARED_STMTS ){
            n = MAX_PREPARED_STMTS;
          }
          pDb->maxStmt = n;
        }
      }
    }else{
      Tcl_AppendResult( interp, "bad option \"", 
          Tcl_GetStringFromObj(objv[0],0), "\": must be flush or size", 0);
      return TCL_ERROR;
    }
    break;
  }

  /*     $db changes
  **
  ** Return the number of rows that were modified, inserted, or deleted by
  ** the most recent INSERT, UPDATE or DELETE statement, not including 
  ** any changes made by trigger programs.
  */
  case DB_CHANGES: {
    Tcl_Obj *pResult;
    if( objc!=2 ){
      Tcl_WrongNumArgs(interp, 2, objv, "");
      return TCL_ERROR;
    }
    pResult = Tcl_GetObjResult(interp);
    Tcl_SetIntObj(pResult, sqlite3_changes(pDb->db));
    break;
  }

  /*    $db close
  **
  ** Shutdown the database
  */
  case DB_CLOSE: {
    Tcl_DeleteCommand(interp, Tcl_GetStringFromObj(objv[0], 0));
    break;
  }

  /*
  **     $db collate NAME SCRIPT
  **
  ** Create a new SQL collation function called NAME.  Whenever
  ** that function is called, invoke SCRIPT to evaluate the function.
  */
  case DB_COLLATE: {
    SqlCollate *pCollate;
    char *zName;
    char *zScript;
    int nScript;
    if( objc!=4 ){
      Tcl_WrongNumArgs(interp, 2, objv, "NAME SCRIPT");
      return TCL_ERROR;
    }
    zName = Tcl_GetStringFromObj(objv[2], 0);
    zScript = Tcl_GetStringFromObj(objv[3], &nScript);
    pCollate = (SqlCollate*)Tcl_Alloc( sizeof(*pCollate) + nScript + 1 );
    if( pCollate==0 ) return TCL_ERROR;
    pCollate->interp = interp;
    pCollate->pNext = pDb->pCollate;
    pCollate->zScript = (char*)&pCollate[1];
    pDb->pCollate = pCollate;
    memcpy(pCollate->zScript, zScript, nScript+1);
    if( sqlite3_create_collation(pDb->db, zName, SQLITE_UTF8, 
        pCollate, tclSqlCollate) ){
      Tcl_SetResult(interp, (char *)sqlite3_errmsg(pDb->db), TCL_VOLATILE);
      return TCL_ERROR;
    }
    break;
  }

  /*
  **     $db collation_needed SCRIPT
  **
  ** Create a new SQL collation function called NAME.  Whenever
  ** that function is called, invoke SCRIPT to evaluate the function.
  */
  case DB_COLLATION_NEEDED: {
    if( objc!=3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "SCRIPT");
      return TCL_ERROR;
    }
    if( pDb->pCollateNeeded ){
      Tcl_DecrRefCount(pDb->pCollateNeeded);
    }
    pDb->pCollateNeeded = Tcl_DuplicateObj(objv[2]);
    Tcl_IncrRefCount(pDb->pCollateNeeded);
    sqlite3_collation_needed(pDb->db, pDb, tclCollateNeeded);
    break;
  }

  /*    $db commit_hook ?CALLBACK?
  **
  ** Invoke the given callback just before committing every SQL transaction.
  ** If the callback throws an exception or returns non-zero, then the
  ** transaction is aborted.  If CALLBACK is an empty string, the callback
  ** is disabled.
  */
  case DB_COMMIT_HOOK: {
    if( objc>3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "?CALLBACK?");
      return TCL_ERROR;
    }else if( objc==2 ){
      if( pDb->zCommit ){
        Tcl_AppendResult(interp, pDb->zCommit, 0);
      }
    }else{
      char *zCommit;
      int len;
      if( pDb->zCommit ){
        Tcl_Free(pDb->zCommit);
      }
      zCommit = Tcl_GetStringFromObj(objv[2], &len);
      if( zCommit && len>0 ){
        pDb->zCommit = Tcl_Alloc( len + 1 );
        memcpy(pDb->zCommit, zCommit, len+1);
      }else{
        pDb->zCommit = 0;
      }
      if( pDb->zCommit ){
        pDb->interp = interp;
        sqlite3_commit_hook(pDb->db, DbCommitHandler, pDb);
      }else{
        sqlite3_commit_hook(pDb->db, 0, 0);
      }
    }
    break;
  }

  /*    $db complete SQL
  **
  ** Return TRUE if SQL is a complete SQL statement.  Return FALSE if
  ** additional lines of input are needed.  This is similar to the
  ** built-in "info complete" command of Tcl.
  */
  case DB_COMPLETE: {
#ifndef SQLITE_OMIT_COMPLETE
    Tcl_Obj *pResult;
    int isComplete;
    if( objc!=3 ){
      Tcl_WrongNumArgs(interp, 2, objv, "SQL");
      return TCL_ERROR;
    }
    isComplete = sqlite3_complete( Tcl_GetStringFromObj(objv[2], 0) );
    pResult = Tcl_GetObjResult(interp);
    Tcl_SetBooleanObj(pResult, isComplete);
#endif
    break;
  }

  /*    $db copy conflict-algorithm table filename ?SEPARATOR? ?NULLINDICATOR?
  **
  ** Copy data into table from filename, optionally using SEPARATOR
  ** as column separators.  If a column contains a null string, or the
  ** value of NULLINDICATOR, a NULL is inserted for the column.
  ** conflict-algorithm is one of the sqlite conflict algorithms:
  **    rollback, abort, fail, ignore, replace
  ** On success, return the number of lines processed, not necessarily same
  ** as 'db changes' due to conflict-algorithm selected.
  **
  ** This code is basically an implementation/enhancement of
  ** the sqlite3 shell.c ".import" command.
  **
  ** This command usage is equivalent to the sqlite2.x COPY statement,
  ** which imports file data into a table using the PostgreSQL COPY file format:
  **   $db copy $conflit_algo $table_name $filename \t \\N
  */
  case DB_COPY: {
    char *zTable;               /* Insert data into this table */
    char *zFile;                /* The file from which to extract data */
    char *zConflict;            /* The conflict algorithm to use */
    sqlite3_stmt *pStmt;        /* A statement */
    int rc;                     /* Result code */
    int nCol;                   /* Number of columns in the table */
    int nByte;                  /* Number of bytes in an SQL string */
    int i, j;                   /* Loop counters */
    int nSep;                   /* Number of bytes in zSep[] */
    int nNull;                  /* Number of bytes in zNull[] */
    char *zSql;                 /* An SQL statement */
    char *zLine;                /* A single line of input from the file */
    char **azCol;               /* zLine[] broken up into columns */
    char *zCommit;              /* How to commit changes */
    FILE *in;                   /* The input file */
    int lineno = 0;             /* Line number of input file */
    char zLineNum[80];          /* Line number print buffer */
    Tcl_Obj *pResult;           /* interp result */

    char *zSep;
    char *zNull;
    if( objc<5 || objc>7 ){
      Tcl_WrongNumArgs(interp, 2, objv, 
         "CONFLICT-ALGORITHM TABLE FILENAME ?SEPARATOR? ?NULLINDICATOR?");
      return TCL_ERROR;
    }
    if( objc>=6 ){
      zSep = Tcl_GetStringFromObj(objv[5], 0);
    }else{
      zSep = "\t";
    }
    if( objc>=7 ){
      zNull = Tcl_GetStringFromObj(objv[6], 0);
    }else{
      zNull = "";
    }
    zConflict = Tcl_GetStringFromObj(objv[2], 0);
    zTable = Tcl_GetStringFromObj(objv[3], 0);