/* 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 <stdio.h>
#include "gfcursor.h"
void ErrorNotification(void);
void ErrorNotification(void) {
printf("Error encountered.\n");
}
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;
long double ld;
char newchar;
char *str;
unsigned char *buffer;
unsigned long filelen;
enum OTYPE objtype;
CURSOR *c = new_CURSOR(NULL,
"newfile",
AM_SHARED,
NULL,
0);
eCursorQueryValid(c, &valid);
if (!valid)
exit(1);
/* Check that the file has contents. */
eObjQueryAggregateEmpty(c, &answer);
if (answer)
exit(1);
eCursorMoveIn(c);
eCursorQueryOnObject(c, &answer);
while (answer) {
eObjQueryType(c, &objtype, NULL);
switch (objtype) {
case OT_SINT:
eObjQueryDataSize(c, &objsize);
switch (objsize) {
case 1: /* signed char */
eObjReadSignedChar(c, &sc);
printf("sc = %d\n", (int)sc);
break;
case 2: /* short */
eObjReadShort(c, &s);
printf("s = %hd\n", s);
break;
case 4: /* long */
eObjReadLong(c, &l);
printf("l = %ld\n", l);
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 OT_UINT:
eObjQueryDataSize(c, &objsize);
switch (objsize) {
case 1: /* unsigned char */
eObjReadUnsignedChar(c, &uc);
printf("uc = %u\n", (unsigned int)uc);
break;
case 2: /* unsigned short */
eObjReadUnsignedShort(c, &us);
printf("us = %hu\n", us);
break;
case 4: /* unsigned long */
eObjReadUnsignedLong(c, &ul);
printf("ul = %lu\n", ul);
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 OT_FLT:
eObjQueryDataSize(c, &objsize);
switch (objsize) {
case 4: /* float */
eObjReadFloat(c, &f);
printf("f = %f\n", f);
break;
case 8: /* double */
eObjReadDouble(c, &d);
printf("d = %f\n", d);
break;
case 10: /* long double */
eObjReadLongDouble(c, &ld);
printf("ld = %Lf\n", ld);
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 OT_CHAR: /* character */
eObjReadChar(c, &newchar);
printf("newchar = %c\n", newchar);
break;
case OT_STR: /* string */
eObjQueryDataSize(c, &objsize);
str = malloc(objsize);
eObjReadString(c, str, objsize);
printf("str = %s\n", str);
free (str);
break;
case OT_BIN: /* binary */
eObjQueryDataSize(c, &objsize);
buffer = malloc(objsize);
eObjReadBinary(c, buffer, &objsize, 0);
printf("buffer object\n");
free (buffer);
break;
/* The programmer decides to simply read the */
/* length of the stored OSFile object. */
case OT_OSF: /* OS File */
eObjQueryOSFileLength(c, &filelen);
printf("File length = %lu\n", filelen);
break;
case 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 (eCursorMoveNext(c, OT_OBJ))
answer = 0;
} /* end while statement */
delete_CURSOR (c);
return 0;
}
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