Function quota_convert

tools/libutil/quotafile.c:516–607

* Convert a quota file from one format to another. */

 * Convert a quota file from one format to another.
 */
int
quota_convert(struct quotafile *qf, int wordsize)
{
	struct quotafile *newqf;
	struct dqhdr64 dqh;
	struct dqblk dqblk;
	struct group *grp;
	int serrno, maxid, id, fd;

	/*
	 * Quotas must not be active and quotafile must be open
	 * for reading and writing.
	 */
	if ((qf->accmode & O_RDWR) != O_RDWR || qf->fd == -1) {
		errno = EBADF;
		return (-1);
	}
	if ((wordsize != 32 && wordsize != 64) ||
	     wordsize == qf->wordsize) {
		errno = EINVAL;
		return (-1);
	}
	maxid = quota_maxid(qf);
	if ((newqf = calloc(1, sizeof(*qf))) == NULL) {
		errno = ENOMEM;
		return (-1);
	}
	*newqf = *qf;
	snprintf(newqf->qfname, MAXPATHLEN + 1, "%s_%d.orig", qf->qfname,
	    qf->wordsize);
	if (rename(qf->qfname, newqf->qfname) < 0) {
		free(newqf);
		return (-1);
	}
	if ((newqf->fd = open(qf->qfname, O_RDWR|O_CREAT|O_TRUNC|O_CLOEXEC,
	    0)) < 0) {
		serrno = errno;
		goto error;
	}
	newqf->wordsize = wordsize;
	if (wordsize == 64) {
		memset(&dqh, 0, sizeof(dqh));
		memcpy(dqh.dqh_magic, Q_DQHDR64_MAGIC, sizeof(dqh.dqh_magic));
		dqh.dqh_version = htobe32(Q_DQHDR64_VERSION);
		dqh.dqh_hdrlen = htobe32(sizeof(struct dqhdr64));
		dqh.dqh_reclen = htobe32(sizeof(struct dqblk64));
		if (write(newqf->fd, &dqh, sizeof(dqh)) != sizeof(dqh)) {
			serrno = errno;
			goto error;
		}
	}
	grp = getgrnam(QUOTAGROUP);
	fchown(newqf->fd, 0, grp ? grp->gr_gid : 0);
	fchmod(newqf->fd, 0640);
	for (id = 0; id <= maxid; id++) {
		if ((quota_read(qf, &dqblk, id)) < 0)
			break;
		switch (newqf->wordsize) {