Getting Started with QNX Neutrino - QNX Software Systems

atoz.c
© 2009, QNX Software Systems GmbH & Co. KG.
dirent_fill (struct dirent *dp, int inode, int offset, char *fname)
{
dp -> d_ino = inode;
dp -> d_offset = offset;
strcpy (dp -> d_name, fname);
dp -> d_namelen = strlen (dp -> d_name);
dp -> d_reclen = ALIGN (sizeof (struct dirent) - 4 + dp -> d_namelen);
return ((struct dirent *) ((char *) dp + dp -> d_reclen));
}
static int
my_read_dir (resmgr_context_t *ctp, io_read_t *msg, iofunc_ocb_t *ocb)
{
int nbytes;
int nleft;
struct dirent *dp;
char *reply_msg;
char fname [_POSIX_PATH_MAX];
// allocate a buffer for the reply
reply_msg = calloc (1, msg -> i.nbytes);
if (reply_msg == NULL) {
return (ENOMEM);
}
// assign output buffer
dp = (struct dirent *) reply_msg;
// we have "nleft" bytes left
nleft = msg -> i.nbytes;
while (ocb -> offset < NUM_ENTS) {
// create the filename
sprintf (fname, "%c", ocb -> offset + ’a’);
// see how big the result is
nbytes = dirent_size (fname);
// do we have room for it?
if (nleft - nbytes >= 0) {
// fill the dirent, and advance the dirent pointer
dp = dirent_fill (dp, ocb -> offset + 1, ocb -> offset, fname);
// move the OCB offset
ocb -> offset++;
// account for the bytes we just used up
nleft -= nbytes;
} else {
}
}
// don’t have any more room, stop
break;
// return info back to the client
MsgReply (ctp -> rcvid, (char *) dp - reply_msg, reply_msg,
(char *) dp - reply_msg);
// release our buffer
free (reply_msg);
314 Appendix: C • Sample Programs April 30, 2009