/*
///////////////////////////////////////////////////////////////
//                                                           //
// open.c     -  gets a stream definition from user          //
// ver 1.0                                                   //
//               definitions                                 //
//                                                           //
// Language:     Borland C, ver 3.0                          //
// Platform:     Gateway 386/25, win95.400                   //
// Application:  CSE784 demonstration                        //
// Author:       Jim Fawcett, 123 Link Hall, Syracuse Univ.  //
//                (315) 443-2654, jfawcett@cat.syr.edu       //
//                                                           //
///////////////////////////////////////////////////////////////
*/

#include <stdlib.h>       /* free()    */
#include <string.h>       /* strcmp()  */
#include "lines.h"        /* getLine() */
#include "open.h"

/*----< open a stream for reading >----------------------------

  Inputs:
  - name of file to open - if null then user response from
    keyboard
  Outputs:
  - returns a FILE pointer to an open stream if file creation
    is successful, otherwise returns 0
*/

FILE *getRStream(char *name) {

  FILE *fptr;
  if(!name) {
    fprintf(stdout,"  please enter a filename for input: ");
    name = getLine(stdin);
    if(!(fptr=fopen(name,"r")))
      fprintf(stdout, "  can't open file %s\n", name);
    free(name);
    return fptr;
  }
  if(!strcmp(name,"stdin"))
    return stdin;
  if(!(fptr=fopen(name,"r")))
    fprintf(stdout, "  can't open file %s\n", name);
  return fptr;
}

/**/

/*----< open a stream for writing >----------------------------

  Inputs:
  - name of file to open - if null then user response from
    keyboard
  Outputs:
  - returns a FILE pointer to an open stream if file creation
    is successful, otherwise returns 0
*/

FILE *getWStream(char *name) {

  FILE *fptr;
  if(!name) {
    fprintf(stdout, "  please enter a filename for output: ");
    name = getLine(stdin);
    if(!(fptr=fopen(name,"w")))
      fprintf(stdout, "  can't open file %s\n", name);
    free(name);
    return fptr;
  }
  if(!strcmp(name,"stdout"))
    return stdout;
  if(!(fptr=fopen(name,"w")))
    fprintf(stdout, "  can't open file %s\n", name);
  return fptr;
}

/*----< test stub >------------------------------------------*/

#ifdef TEST_OPEN
#include "lines.c"    /* don't include implementation files  */
                      /* except in test stubs:               */
                      /*   including avoids need for project */

void main() {

   FILE   *in = getRStream(0);
   FILE  *out = getWStream(0);
   char *line = getLine(in);
   fprintf(out, "%s\n", line);
   fprintf(stdout, "just wrote %s to output file\n", line);

}

#endif