/* Gamelon(tm) File I/O Library Sample Code C++ Language */
/* (C)1994 Menai Corporation(tm) Released for public use */
/* Example 9b. How to read the contents of stored objects */
/* when structure of the file is unknown. */
/* If the structure of the file is unknown, the program */
/* must first determine the datatype of each object */
/* before selecting the appropriate function with which */
/* to read the value within the object. In this example, */
/* we have used the variable sizes common to personal */
/* computers. */
/* Beginning file layout: */
/* { } */
/* [14]['F']["Wherefore art thou, Romeo?"] */
#include <stdlib.h>
#include <iostream.h>
#include "gfcursor.hpp"
void ErrorNotification(void);
void ErrorNotification(void) {
cerr << "Error encountered." << endl;
}
int main(void) {
/* Declare a few variables which will be used. */
int answer;
int valid;
size_t objsize;
signed char sc;
short s;
long l;
unsigned char uc;
unsigned short us;
unsigned long ul;
float f;
double d;
char newchar;
char *str;
unsigned char *buffer;
unsigned long filelen;
CURSOR::OTYPE objtype;
CURSOR *c = new CURSOR("newfile");
c>eCursorQueryValid(&valid);
if (!valid)
exit(1);
/* Check that the file has contents. */
c>eObjQueryAggregateEmpty(&answer);
if (answer)
exit(1);
c>eCursorMoveIn();
c>eCursorQueryOnObject(&answer);
while (answer) {
c>eObjQueryType(&objtype);
switch (objtype) {
case CURSOR::OT_AGGR: /* aggregate object */
cout << "aggregate" << endl;
break;
case CURSOR::OT_SINT:
c>eObjQueryDataSize(&objsize);
switch (objsize) {
case 1: /* signed char */
c>eObjRead(&sc);
cout << "sc = " << sc << endl;
break;
case 2: /* short */
c>eObjRead(&s);
cout << "s = " << s << endl;
break;
case 4: /* long */
c>eObjRead(&l);
cout << "l = " << l << endl;
break;
default:
/* Programmer decides not to try to handle oddsized */
/* signed integers other than to indicate an error. */
ErrorNotification();
} /* end OT_SINT switch */
break;
case CURSOR::OT_UINT:
c>eObjQueryDataSize(&objsize);
switch (objsize) {
case 1: /* unsigned char */
c>eObjRead(&uc);
cout << "uc = " << uc << endl;
break;
case 2: /* unsigned short */
c>eObjRead(&us);
cout << "us = " << us << endl;
break;
case 4: /* unsigned long */
c>eObjRead(&ul);
cout << "ul = " << ul << endl;
break;
default:
/* Programmer decides not to try to handle oddsized */
/* unsigned integers other than to indicate an error.*/
ErrorNotification();
} /* end OT_UINT switch */
break;
case CURSOR::OT_FLT:
c>eObjQueryDataSize(&objsize);
switch (objsize) {
case 4: /* float */
c>eObjRead(&f);
cout << "f = " << f << endl;
break;
case 8: /* double */
c>eObjRead(&d);
cout << "d = " << d << endl;
break;
default:
/* Programmer decides not to try to handle odd */
/* sized floats other than to indicate an error.*/
ErrorNotification();
} /* end OT_FLT switch */
break;
case CURSOR::OT_CHAR: /* character */
c>eObjRead(&newchar);
cout << "newchar = " << newchar << endl;
break;
case CURSOR::OT_STR: /* string */
c>eObjQueryDataSize(&objsize);
str = new char[objsize];
c>eObjRead(str, objsize);
cout << "str = " << str << endl;
delete str;
break;
case CURSOR::OT_BIN: /* binary */
c>eObjQueryDataSize(&objsize);
buffer = new unsigned char[objsize];
c>eObjRead(buffer, &objsize);
cout << "buffer object" << endl;
delete buffer;
break;
/* The programmer decides to simply read the */
/* length of the stored OSFile object. */
case CURSOR::OT_OSF: /* OS File */
c>eObjQueryOSFileLength(&filelen);
cout << "File length = " << filelen << endl;
break;
case CURSOR::OT_BAD: /* bad object */
/* Programmer decides not to try to handle bad */
/* objects other than to indicate an error. */
ErrorNotification();
break;
default:
/* Programmer decides not to try to handle unrecog */
/* nized objects other than to indicate an error. */
ErrorNotification();
} /* end objtype switch */
/* Do something with the value just read. */
if (c>eCursorMoveNext())
answer = 0;
} /* end while statement */
delete c;
return 0;
}
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