/*
 * NAME
 *  libosint.c - C function to show example usage of 
 *  Oracle8 external procedure.
 *
 * OVERVIEW
 *  This program contains the function "RunOSCmd" 
 *  called from the Oracle stored procedure 
 *  "osutil.RunOsCmd". For more Information on 
 *  Service Routines see PL/SQL Users Guide Oracle-8
 *  on Page 10-14
*/

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <sys/types.h>

#ifndef OCI_ORACLE
#include <oci.h>
#endif

/*
 *  RunOsCmd - This function runs the OS command 
 *  pointed to by "cmd". The output of this command 
 *  is returned via the cmdo ptr.
 */
void RunOsCmd(ctx, cmd, cmd_ind, cmd_len, cmdo, cmdo_ind, cmdo_len)
OCIExtProcContext *ctx;    /* Oracle ConText Pointer        */
char  *cmd;                /* Pointer to OS command         */
short cmd_ind;             /* Null Indicator for OS command */
int   cmd_len;             /* Length indicator variable     */
char  *cmdo;               /* Pointer to OS command output  */
short *cmdo_ind;           /* Null Indicator for OS command */
int   *cmdo_len;           /* Length indicator variable     */
{
  char cmdbuf[BUFSIZ];     /* buffer to hold command output */
  FILE *fptr;              /* pipe pointer for OS command   */
  int  PLSQLBSZ = 32767;   /* Max PL/SQL output buffer size */

  *cmdo = '\0';            /* initialize output variables */
  *cmdo_len = 0;

  if (cmd_ind == OCI_IND_NULL)     {
   strcpy(cmdo,"Command entered cannot be NULL...");
   *cmdo_ind = (short)OCI_IND_NOTNULL;
   *cmdo_len =  30;
 }  else   {
    if ((fptr = popen(cmd, "r")) != NULL) {     /* Execute command */  
       while (fgets(cmdbuf, BUFSIZ, fptr) != NULL)  {
         strcat(cmdo, cmdbuf);                  /* Build output string */
        *cmdo_len = *cmdo_len + strlen(cmdbuf);
       }
       if (*cmdo == NULL) {
          *cmdo_ind = (short)OCI_IND_NULL;
       } else {
         *cmdo_ind = (short)OCI_IND_NOTNULL;
         if (*cmdo_len > PLSQLBSZ) {      /* Trunc output to max buf sz */
             *cmdo_len = PLSQLBSZ;
             cmdo[PLSQLBSZ - 1] = '\0';
          }
       }
      pclose(fptr);  /* Close the pipe */
      } else {
         printf("\nUnable to open FPTR\n");   /* Some OS error occurred */
         *cmdo_ind = (short)OCI_IND_NULL;
         *cmdo_len = 0;
      }
  }
} /* End of RunOsCmd */