fcc_destry.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* lib/krb5/ccache/file/fcc_destry.c
*
* Copyright 1990 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* This file contains the source code for krb5_fcc_destroy.
*/
#include <errno.h>
#include "fcc.h"
/*
* Effects:
* Destroys the contents of id.
*
* Errors:
* system errors
*/
krb5_error_code KRB5_CALLCONV
krb5_fcc_destroy(context, id)
krb5_context context;
krb5_ccache id;
{
struct stat buf;
unsigned long i, size;
unsigned int wlen;
char zeros[BUFSIZ];
register int ret;
krb5_error_code kret = 0;
if (OPENCLOSE(id)) {
ret = THREEPARAMOPEN(((krb5_fcc_data *) id->data)->filename, O_RDWR | O_BINARY, 0);
if (ret < 0) {
kret = krb5_fcc_interpret(context, errno);
goto cleanup;
}
((krb5_fcc_data *) id->data)->fd = ret;
}
else
lseek(((krb5_fcc_data *) id->data)->fd, 0, SEEK_SET);
#ifdef MSDOS_FILESYSTEM
/* "disgusting bit of UNIX trivia" - that's how the writers of NFS describe
** the ability of UNIX to still write to a file which has been unlinked.
** Naturally, the PC can't do this. As a result, we have to delete the file
** after we wipe it clean but that throws off all the error handling code.
** So we have do the work ourselves.
*/
ret = fstat(((krb5_fcc_data *) id->data)->fd, &buf);
if (ret == -1) {
kret = krb5_fcc_interpret(context, errno);
size = 0; /* Nothing to wipe clean */
} else
size = (unsigned long) buf.st_size;
memset(zeros, 0, BUFSIZ);
while (size > 0) {
wlen = (int) ((size > BUFSIZ) ? BUFSIZ : size); /* How much to write */
i = write(((krb5_fcc_data *) id->data)->fd, zeros, wlen);
if (i < 0) {
kret = krb5_fcc_interpret(context, errno);
/* Don't jump to cleanup--we still want to delete the file. */
break;
}
size -= i; /* We've read this much */
}
if (OPENCLOSE(id)) {
(void) close(((krb5_fcc_data *)id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
}
ret = unlink(((krb5_fcc_data *) id->data)->filename);
if (ret < 0) {
kret = krb5_fcc_interpret(context, errno);
goto cleanup;
}
#else /* MSDOS_FILESYSTEM */
ret = unlink(((krb5_fcc_data *) id->data)->filename);
if (ret < 0) {
kret = krb5_fcc_interpret(context, errno);
if (OPENCLOSE(id)) {
(void) close(((krb5_fcc_data *)id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
kret = ret;
}
goto cleanup;
}
ret = fstat(((krb5_fcc_data *) id->data)->fd, &buf);
if (ret < 0) {
kret = krb5_fcc_interpret(context, errno);
if (OPENCLOSE(id)) {
(void) close(((krb5_fcc_data *)id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
}
goto cleanup;
}
/* XXX This may not be legal XXX */
size = (unsigned long) buf.st_size;
memset(zeros, 0, BUFSIZ);
for (i=0; i < size / BUFSIZ; i++)
if (write(((krb5_fcc_data *) id->data)->fd, zeros, BUFSIZ) < 0) {
kret = krb5_fcc_interpret(context, errno);
if (OPENCLOSE(id)) {
(void) close(((krb5_fcc_data *)id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
}
goto cleanup;
}
wlen = (unsigned int) (size % BUFSIZ);
if (write(((krb5_fcc_data *) id->data)->fd, zeros, wlen) < 0) {
kret = krb5_fcc_interpret(context, errno);
if (OPENCLOSE(id)) {
(void) close(((krb5_fcc_data *)id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
}
goto cleanup;
}
ret = close(((krb5_fcc_data *) id->data)->fd);
((krb5_fcc_data *) id->data)->fd = -1;
if (ret)
kret = krb5_fcc_interpret(context, errno);
#endif /* MSDOS_FILESYSTEM */
cleanup:
krb5_xfree(((krb5_fcc_data *) id->data)->filename);
krb5_xfree(id->data);
krb5_xfree(id);
krb5_change_cache ();
return kret;
}