/* Copyright © 1995, 2002, Oracle Corporation.  All Rights Reserved. */


#pragma module SQL_DYNAMIC_DRIVER_I "IDENT"
   
/*
**++
**  ABSTRACT:	sql_dynamic_driver_i.c
**
**      This program is an interactive demo which executes any valid
**	SQL statement dynamically.
**
**	It is the main driver for a set of Dynamic SQL routines which process 
**	any valid SQL statement.  Associated with this program are
**	the following modules:
**
**	   . sql_dynamic.c         : processes statements passed by 
**				      sql_dynamic_driver_i.c
**
**	   . sql_dynamic_c.sqlmod  : SQL module language file 
**			             that contains all the procedures called by 
**			             sql_dynamic_driver_m.c
**
**/


/*
**
**  INCLUDE FILES
**
**/

#include <stdio.h>
#include <descrip.h>
#include <ssdef.h>
#include <stdlib.h>
#include <string.h>

/* Declarations
*/

#define MAX_STMT_SIZE 2048	/* max length of a statement to be processed */

/* Main routine which processes the dynamic SQL statements passed to it. */

extern int sql_dynamic();

void read_from_file ();
void call_main_program ();

/*
**
**  Main Program 
**
*/

main ()
{
char sql_statement[MAX_STMT_SIZE+1];   /* the sql statement input by the user */
char *pstmt = &sql_statement[0];
char * bp;
char *null_stmt;	/* template for blanking out buffer */
int   i, status;
char  *semicolon;

/* Use calloc to initialize a piece of zeroed memory */
null_stmt = (char *) calloc (MAX_STMT_SIZE+1, sizeof(char));

printf ("\nThis program processes valid SQL statements using Dynamic SQL.");

sql_statement[0] = ' ';

while (*pstmt != 0)
{

    /* Prompt the user for the statement to be executed */

    printf ("\n\nEnter the SQL statement to process, terminating your");
    printf ("\nstatement with a semicolon <;> <<Enter> or <Ctrl/Z> to exit>:");
    printf ("\n\nDynamicSQL> ");

    bp = gets (pstmt);
    if (bp == NULL)
	/* the user entered <Enter> or <Ctrl/Z> to terminate */
	exit (EXIT_SUCCESS);

    if (*pstmt != 0) 	/* user does not want to exit */
    {
	/* Check for ; to end the statement; else prompt for rest of stmt */
	while ((semicolon = strchr(pstmt, ';')) == 0)
	{
	    /* The gets function replaces the end of the input string
	     * with a \0.  Find it now and replace with space and
	     * append the next line to the buffer		     */
	    pstmt = strchr (pstmt, 0);
	    *pstmt = ' ';

	    /* fetch into the buffer */
	    printf ("\ncont> ");
	    bp = gets (pstmt+1);
	    if (bp == NULL)
		/* the user entered <Enter> or <Ctrl/Z> to terminate */
		exit (EXIT_SUCCESS);
	}

        if ( sql_statement[0] == '@' )
        {
            char filename[50];
            sscanf( &(sql_statement[sql_statement[1]==' ' ? 2 : 1]),
		    "%s", filename);
            read_from_file(filename);
        }
        else
            call_main_program(sql_statement);
            
	strncpy (sql_statement, null_stmt, MAX_STMT_SIZE+1);
	pstmt = &sql_statement[0];
	sql_statement[0] = ' ';
        
    }  /* end if *pstmt != 0 */

}	/* end while */

} /* end main */

void read_from_file (char * fnam)
{    
char sql_statement[MAX_STMT_SIZE+1];   /* the sql statement input by the user */
char *pstmt = &sql_statement[0];
char sql_statement2[MAX_STMT_SIZE+1];   /* the sql statement input by the user */
char *pstmt2 = &sql_statement2[0];
FILE *fid;
char *newline;

sql_statement[0] = ' ';
sql_statement2[0] = ' ';

/* Open the file */
if ((fid = fopen(fnam, "r", "dna=.COM")) == 0)
{
    printf("\n\nCould not open '%s' for input.\n\n\7",fnam);
    exit (EXIT_FAILURE);
}

while ( fgets(pstmt,sizeof(sql_statement),fid) != 0)
{
    if ((pstmt[0] == '\0') || (pstmt[0] == '\n'))
	/* blank like terminates input */
	break;

    /* read lines until we get to the terimating ';' */
    while (strchr(pstmt, ';') == 0)
    {
	newline = strchr(pstmt, '\n');
	if (newline != 0)
	{
	    *newline = ' ';
	    pstmt = newline;
	}

	if (fgets(pstmt2,sizeof(sql_statement2),fid) == 0) break;
	strcat(sql_statement, sql_statement2);
	memset (sql_statement2, '\0', MAX_STMT_SIZE+1);
	sql_statement2[0] = ' ';
    }

    /* now execute the statement */
    call_main_program(sql_statement);

    memset (sql_statement, '\0', MAX_STMT_SIZE+1);
    pstmt = &sql_statement[0];
    sql_statement[0] = ' ';
}

fclose(fid);

}

void call_main_program (char * sqlstatement)
{
/* 
 * The following "dummy" variables are needed as parameters to the routine
 * sql_dynamic.   They would be needed if re-executing statements
 * without having to re-PREPARE the statement - a capability of
 * the sql_dynamic routine.  Re-executing statements is not
 * a feature of this demo program (see instead sql_dynamic_driver_m.C)
 */
char *dummy_sqlda_in,	
     *dummy_sqlda_out;
long  dummy_stmt_id;
int dummy_flag = 0;     

int   i, status;
char *semicolon;

printf ("\n\nThe SQL statement to be executed dynamically is:\n %s\n",
	sqlstatement);

/* Some older versions of SQL didn't allow trailing ';' in the string
 * so mask it out */
semicolon = strchr(sqlstatement, ';');
*semicolon = ' ';

dummy_sqlda_in  = NULL;
dummy_sqlda_out = NULL;
dummy_stmt_id   = 0;

if ((status = sql_dynamic(sqlstatement,
                          &dummy_sqlda_in,&dummy_sqlda_out,
                          &dummy_stmt_id,&dummy_flag)) != 0)
    printf ("\nError returned from sql_dynamic()");

}