scst: Separate assignments from conditions and chained updates

Give chained state updates separate statements. Preserve the previous
bio tail when linking a request, then advance it once for either the
first or a subsequent bio.

Move unconditionally evaluated daemon assignments immediately before
their if statements. Preserve call order, errno checks and short-circuit
behavior; leave else-if lookup chains and conditional assignments that
need a separate control-flow decision unchanged.

Checkpatch reports MULTIPLE_ASSIGNMENTS:

  multiple assignments should be avoided

Checkpatch reports ASSIGN_IN_IF:

  do not use assignment in if condition

iscsi-scst/usr/chap.c

@@ -527,7 +527,8 @@ static int chap_initiator_auth_check_response(struct connection *conn)
 		goto out;
 	}
 
-	if (!(value = text_key_find(conn, "CHAP_N"))) {
+	value = text_key_find(conn, "CHAP_N");
+	if (!value) {
 		retval = CHAP_INITIATOR_ERROR;
 		goto out;
 	}
@@ -544,12 +545,14 @@ static int chap_initiator_auth_check_response(struct connection *conn)
 		goto out;
 	}
 
-	if (!(value = text_key_find(conn, "CHAP_R"))) {
+	value = text_key_find(conn, "CHAP_R");
+	if (!value) {
 		retval = CHAP_INITIATOR_ERROR;
 		goto out;
 	}
 
-	if ((encoding_format = chap_check_encoding_format(value)) < 0) {
+	encoding_format = chap_check_encoding_format(value);
+	if (encoding_format < 0) {
 		retval = CHAP_INITIATOR_ERROR;
 		goto out;
 	}
@@ -650,7 +653,8 @@ static int chap_target_auth_create_response(struct connection *conn)
 	int challenge_len = 0, digest_len = 0, retval = 0;
 	int res;
 
-	if (!(value = text_key_find(conn, "CHAP_I"))) {
+	value = text_key_find(conn, "CHAP_I");
+	if (!value) {
 		/* Initiator doesn't want target auth!? */
 		conn->state = STATE_SECURITY_DONE;
 		retval = 0;
@@ -666,14 +670,16 @@ static int chap_target_auth_create_response(struct connection *conn)
 		goto out;
 	}
 
-	if (!(value = text_key_find(conn, "CHAP_C"))) {
+	value = text_key_find(conn, "CHAP_C");
+	if (!value) {
 		log_warning("CHAP target auth.: got no challenge from initiator %s",
 			    conn->initiator);
 		retval = CHAP_INITIATOR_ERROR;
 		goto out;
 	}
 
-	if ((encoding_format = chap_check_encoding_format(value)) < 0) {
+	encoding_format = chap_check_encoding_format(value);
+	if (encoding_format < 0) {
 		retval = CHAP_INITIATOR_ERROR;
 		goto out;
 	}

iscsi-scst/usr/config.c

@@ -387,7 +387,8 @@ int config_account_query(u32 tid, int dir, const char *name, char *pass)
 {
 	struct iscsi_attr *user;
 
-	if (!(user = account_lookup_by_name(tid, dir, name)))
+	user = account_lookup_by_name(tid, dir, name);
+	if (!user)
 		return -ENOENT;
 
 	iscsi_strscpy(pass, ISCSI_USER_PASS(user), ISCSI_NAME_LEN);
@@ -706,13 +707,15 @@ static int __initiator_match(int fd, char *str)
 
 		if (*p == '[') {
 			p++;
-			if (!(q = strchr(p, ']')))
+			q = strchr(p, ']');
+			if (!q)
 				return 0;
 			*(q++) = '\0';
 		} else
 			q = p;
 
-		if ((q = strchr(q, '/')))
+		q = strchr(q, '/');
+		if (q)
 			*(q++) = '\0';
 
 		memset(&hints, 0, sizeof(hints));
@@ -742,7 +745,8 @@ static int initiator_match(u32 tid, int fd, const char *filename)
 	FILE *fp;
 	char buf[BUFSIZE], *p;
 
-	if (!(fp = fopen(filename, "r")))
+	fp = fopen(filename, "r");
+	if (!fp)
 		return err;
 
 	/*
@@ -816,7 +820,8 @@ int config_target_destroy(u32 tid)
 {
 	int err;
 
-	if ((err = target_del(tid, 0)) < 0)
+	err = target_del(tid, 0);
+	if (err < 0)
 		return err;
 
 	return err;

iscsi-scst/usr/ctldev.c

@@ -165,7 +165,8 @@ int kernel_target_create(struct target *target, u32 *tid, u32 cookie)
 	log_debug(1, "Adding target %s (attrs_num %d)", target->name,
 		info.attrs_num);
 
-	if ((err = ioctl(ctrl_fd, ADD_TARGET, &info)) < 0) {
+	err = ioctl(ctrl_fd, ADD_TARGET, &info);
+	if (err < 0) {
 		err = -errno;
 		log_error("Can't create target %s: %s\n", target->name,
 			strerror(errno));
@@ -262,7 +263,8 @@ int kernel_initiator_allowed(u32 tid, const char *full_initiator_name)
 	iscsi_strscpy(info.full_initiator_name, full_initiator_name,
 		      sizeof(info.full_initiator_name));
 
-	if ((err = ioctl(ctrl_fd, ISCSI_INITIATOR_ALLOWED, &info)) < 0) {
+	err = ioctl(ctrl_fd, ISCSI_INITIATOR_ALLOWED, &info);
+	if (err < 0) {
 		err = -errno;
 		log_error("Can't find out initiator %s permissions (%s, "
 			  "tid %u", full_initiator_name, strerror(errno), tid);
@@ -280,7 +282,8 @@ int kernel_conn_destroy(u32 tid, u64 sid, u32 cid)
 	info.sid = sid;
 	info.cid = cid;
 
-	if ((err = ioctl(ctrl_fd, DEL_CONN, &info)) < 0) {
+	err = ioctl(ctrl_fd, DEL_CONN, &info);
+	if (err < 0) {
 		err = -errno;
 		log_debug(2, "Can't destroy conn (%s, tid %u, sid 0x%"
 			  PRIx64 ", cid %u\n", strerror(errno), tid, sid, cid);
@@ -305,7 +308,8 @@ int kernel_params_get(u32 tid, u64 sid, int type, struct iscsi_param *params)
 	info.sid = sid;
 	info.params_type = type;
 
-	if ((err = ioctl(ctrl_fd, ISCSI_PARAM_GET, &info)) < 0) {
+	err = ioctl(ctrl_fd, ISCSI_PARAM_GET, &info);
+	if (err < 0) {
 		err = -errno;
 		log_debug(1, "Can't get session params for session 0x%" PRIx64
 			" (tid %u, err %d): %s\n", sid, tid, err, strerror(errno));
@@ -347,7 +351,8 @@ int kernel_params_set(u32 tid, u64 sid, int type, u32 partial,
 		for (i = 0; i < target_key_last; i++)
 			info.target_params[i] = params[i].val;
 
-	if ((err = ioctl(ctrl_fd, ISCSI_PARAM_SET, &info)) < 0) {
+	err = ioctl(ctrl_fd, ISCSI_PARAM_SET, &info);
+	if (err < 0) {
 		err = -errno;
 		log_error("Can't set session params for session 0x%" PRIx64
 			" (tid %u, type %d, partial %d, err %d): %s\n", sid,

iscsi-scst/usr/event.c

@@ -172,7 +172,8 @@ static int handle_e_add_target(int fd, const struct iscsi_kern_event *event)
 	offs = sprintf(buf, "Target ");
 
 	while (1) {
-		if ((rc = nl_read(fd, &buf[offs], event->param1_size, true)) < 0) {
+		rc = nl_read(fd, &buf[offs], event->param1_size, true);
+		if (rc < 0) {
 			if ((errno == EINTR) || (errno == EAGAIN))
 				continue;
 			log_error("read netlink fd (%d) failed: %s", fd,
@@ -188,7 +189,8 @@ static int handle_e_add_target(int fd, const struct iscsi_kern_event *event)
 
 	if (event->param2_size > 0) {
 		while (1) {
-			if ((rc = nl_read(fd, &buf[offs], event->param2_size, true)) < 0) {
+			rc = nl_read(fd, &buf[offs], event->param2_size, true);
+			if (rc < 0) {
 				if ((errno == EINTR) || (errno == EAGAIN))
 					continue;
 				log_error("read netlink fd (%d) failed: %s", fd,
@@ -409,7 +411,8 @@ static int handle_e_mgmt_cmd(int fd, const struct iscsi_kern_event *event)
 	}
 
 	while (1) {
-		if ((rc = nl_read(fd, buf, event->param1_size, true)) < 0) {
+		rc = nl_read(fd, buf, event->param1_size, true);
+		if (rc < 0) {
 			if ((errno == EINTR) || (errno == EAGAIN))
 				continue;
 			log_error("read netlink fd (%d) failed: %s", fd,
@@ -501,7 +504,8 @@ static int handle_e_get_attr_value(int fd, const struct iscsi_kern_event *event)
 	}
 
 	while (1) {
-		if ((rc = nl_read(fd, buf, event->param1_size, true)) < 0) {
+		rc = nl_read(fd, buf, event->param1_size, true);
+		if (rc < 0) {
 			if ((errno == EINTR) || (errno == EAGAIN))
 				continue;
 			log_error("read netlink fd (%d) failed: %s", fd,
@@ -818,7 +822,8 @@ static int handle_e_set_attr_value(int fd, const struct iscsi_kern_event *event)
 	}
 
 	while (1) {
-		if ((rc = nl_read(fd, buf, event->param1_size, true)) < 0) {
+		rc = nl_read(fd, buf, event->param1_size, true);
+		if (rc < 0) {
 			if ((errno == EINTR) || (errno == EAGAIN))
 				continue;
 			log_error("read netlink fd (%d) failed: %s", fd,
@@ -833,7 +838,8 @@ static int handle_e_set_attr_value(int fd, const struct iscsi_kern_event *event)
 	offs += sprintf(&buf[offs], " ");
 
 	while (1) {
-		if ((rc = nl_read(fd, &buf[offs], event->param2_size, true)) < 0) {
+		rc = nl_read(fd, &buf[offs], event->param2_size, true);
+		if (rc < 0) {
 			if ((errno == EINTR) || (errno == EAGAIN))
 				continue;
 			log_error("read netlink fd (%d) failed: %s", fd,

iscsi-scst/usr/iscsi_adm.c

@@ -221,12 +221,14 @@ static int iscsid_request(struct iscsi_adm_req *req, void *rsp_data,
 {
 	int fd, err;
 
-	if ((fd = iscsid_connect()) < 0) {
+	fd = iscsid_connect();
+	if (fd < 0) {
 		err = fd;
 		goto out_close;
 	}
 
-	if ((err = iscsid_request_send(fd, req)) < 0)
+	err = iscsid_request_send(fd, req);
+	if (err < 0)
 		goto out_report;
 
 	err = iscsid_response_recv(fd, req, rsp_data, rsp_data_sz);
@@ -283,11 +285,13 @@ static int parse_trgt_params(struct msg_trgt *msg, char *params)
 
 		if (!*p)
 			continue;
-		if (!(q = strchr(p, '=')))
+		q = strchr(p, '=');
+		if (!q)
 			continue;
 		*q++ = '\0';
 
-		if (!((idx = params_index_by_name(p, target_keys)) < 0)) {
+		idx = params_index_by_name(p, target_keys);
+		if (idx >= 0) {
 			if (params_str_to_val(target_keys, idx, q, &val)) {
 				fprintf(stderr,
 					"Invalid %s value \"%s\".\n",
@@ -302,7 +306,8 @@ static int parse_trgt_params(struct msg_trgt *msg, char *params)
 			continue;
 		}
 
-		if (!((idx = params_index_by_name(p, session_keys)) < 0)) {
+		idx = params_index_by_name(p, session_keys);
+		if (idx >= 0) {
 			if (params_str_to_val(session_keys, idx, q, &val)) {
 				fprintf(stderr,
 					"Invalid %s value \"%s\".\n",
@@ -418,7 +423,8 @@ static int parse_user_params(char *params, u32 *auth_dir, char **user,
 		if (!*p)
 			continue;
 
-		if (!(q = strchr(p, '=')))
+		q = strchr(p, '=');
+		if (!q)
 			continue;
 		*q++ = '\0';
 		if (isspace(*q))

iscsi-scst/usr/iscsi_scstd.c

@@ -441,7 +441,8 @@ static void accept_connection(int listen)
 	char target_portal[ISCSI_PORTAL_LEN], target_portal_port[NI_MAXSERV];
 
 	namesize = sizeof(from);
-	if ((fd = accept(listen, &from.sa, &namesize)) < 0) {
+	fd = accept(listen, &from.sa, &namesize);
+	if (fd < 0) {
 		switch (errno) {
 		case EINTR:
 		case EAGAIN:
@@ -952,12 +953,14 @@ int main(int argc, char **argv)
 		}
 	}
 
-	if ((ctrl_fd = kernel_open()) < 0)
+	ctrl_fd = kernel_open();
+	if (ctrl_fd < 0)
 		exit(-1);
 
 	init_max_params();
 
-	if ((nl_fd = nl_open()) < 0) {
+	nl_fd = nl_open();
+	if (nl_fd < 0) {
 		perror("netlink open failed");
 		exit(-1);
 	}
@@ -982,7 +985,8 @@ int main(int argc, char **argv)
 	if (err != 0)
 		exit(err);
 
-	if ((ipc_fd = iscsi_adm_request_listen()) < 0) {
+	ipc_fd = iscsi_adm_request_listen();
+	if (ipc_fd < 0) {
 		perror("Opening AF_LOCAL socket failed");
 		exit(-1);
 	}

iscsi-scst/usr/iscsid.c

@@ -85,7 +85,8 @@ static char *next_key(char **data, int *datasize, char **value)
 	char *key, *p, *q;
 	int size = *datasize;
 
-	key = p = *data;
+	p = *data;
+	key = p;
 	for (; size > 0 && *p != '='; p++, size--)
 		;
 	if (!size)

iscsi-scst/usr/isns.c

@@ -117,7 +117,8 @@ static int isns_get_ip(int fd)
 	case AF_INET:
 		addr = lss.sin.sin_addr.s_addr;
 
-		ip[10] = ip[11] = 0xff;
+		ip[11] = 0xff;
+		ip[10] = 0xff;
 		ip[15] = 0xff & (addr >> 24);
 		ip[14] = 0xff & (addr >> 16);
 		ip[13] = 0xff & (addr >> 8);

iscsi-scst/usr/message.c

@@ -40,12 +40,14 @@ int iscsi_adm_request_listen(void)
 	memcpy((char *) &addr.sun_path + 1, ISCSI_ADM_NAMESPACE,
 		strlen(ISCSI_ADM_NAMESPACE));
 
-	if ((err = bind(fd, (struct sockaddr *) &addr, sizeof(addr))) < 0) {
+	err = bind(fd, (struct sockaddr *) &addr, sizeof(addr));
+	if (err < 0) {
 		close(fd);
 		return err;
 	}
 
-	if ((err = listen(fd, 32)) < 0) {
+	err = listen(fd, 32);
+	if (err < 0) {
 		close(fd);
 		return err;
 	}
@@ -161,7 +163,8 @@ int iscsi_adm_request_handle(int accept_fd)
 
 	memset(&rsp, 0, sizeof(rsp));
 	len = sizeof(addr);
-	if ((fd = accept(accept_fd, (struct sockaddr *) &addr, &len)) < 0) {
+	fd = accept(accept_fd, (struct sockaddr *) &addr, &len);
+	if (fd < 0) {
 		if (errno == EINTR)
 			err = -EINTR;
 		else
@@ -171,7 +174,8 @@ int iscsi_adm_request_handle(int accept_fd)
 	}
 
 	len = sizeof(cred);
-	if ((err = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void *) &cred, &len)) < 0) {
+	err = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void *) &cred, &len);
+	if (err < 0) {
 		rsp.err = -EPERM;
 		goto send;
 	}
@@ -181,7 +185,8 @@ int iscsi_adm_request_handle(int accept_fd)
 		goto send;
 	}
 
-	if ((err = read(fd, &req, sizeof(req))) != sizeof(req)) {
+	err = read(fd, &req, sizeof(req));
+	if (err != sizeof(req)) {
 		if (err >= 0)
 			err = -EIO;
 		goto out;

iscsi-scst/usr/misc.c

@@ -84,7 +84,8 @@ int create_and_open_dev(const char *dev, int readonly)
 	else
 		flags = O_RDWR;
 
-	err = ctlfd = open(devname, flags);
+	ctlfd = open(devname, flags);
+	err = ctlfd;
 	if (ctlfd < 0) {
 		err = -errno;
 		printf("cannot open %s %s\n", devname, strerror(errno));

iscsi-scst/usr/param.c

@@ -226,7 +226,8 @@ static int digest_str_to_val(const char *str, unsigned int *val)
 			break;
 		}
 
-		if ((q = strchr(p, ',')))
+		q = strchr(p, ',');
+		if (q)
 			p = q + 1;
 	} while (q);
 

iscsi-scst/usr/session.c

@@ -38,7 +38,8 @@ static int session_alloc(u32 tid, struct session **psess)
 		goto out;
 	}
 
-	if (!(session = malloc(sizeof(*session)))) {
+	session = malloc(sizeof(*session));
+	if (!session) {
 		res = -ENOMEM;
 		goto out;
 	}
@@ -60,7 +61,8 @@ struct session *session_find_name(u32 tid, const char *iname, union iscsi_sid si
 	struct session *session;
 	struct target *target;
 
-	if (!(target = target_find_by_id(tid))) {
+	target = target_find_by_id(tid);
+	if (!target) {
 		log_error("Target tid %d not found", tid);
 		return NULL;
 	}
@@ -81,7 +83,8 @@ struct session *session_find_id(u32 tid, u64 sid)
 	struct session *session;
 	struct target *target;
 
-	if (!(target = target_find_by_id(tid)))
+	target = target_find_by_id(tid);
+	if (!target)
 		return NULL;
 
 	log_debug(1, "Searching for sid %#" PRIx64, sid);
@@ -99,7 +102,8 @@ static bool session_id_exists(u32 tid, u64 sid, struct session *exclude)
 	struct session *session;
 	struct target *target;
 
-	if (!(target = target_find_by_id(tid)))
+	target = target_find_by_id(tid);
+	if (!target)
 		return false;
 
 	log_debug(1, "Searching for sid %#" PRIx64, sid);

iscsi-scst/usr/target.c

@@ -491,7 +491,8 @@ bool target_redirected(struct target *target, struct connection *conn)
 		goto out;
 	}
 
-	if ((p = strrchr(tmp, '%')))
+	p = strrchr(tmp, '%');
+	if (p)
 		*p = '\0';
 
 	if (sa.sa.sa_family == AF_INET6)

scst/include/backport.h

@@ -2266,7 +2266,8 @@ static inline void scsi_req_init(struct request *rq)
 	rq->cmd_type = REQ_TYPE_BLOCK_PC;
 	rq->__data_len = 0;
 	rq->__sector = (sector_t) -1;
-	rq->bio = rq->biotail = NULL;
+	rq->biotail = NULL;
+	rq->bio = NULL;
 	memset(rq->__cmd, 0, sizeof(rq->__cmd));
 	rq->cmd = rq->__cmd;
 #else

scst/src/dev_handlers/scst_vdisk_main.c

@@ -5901,9 +5901,10 @@ static void blockio_exec_rw(struct vdisk_cmd_params *p, bool write, bool fua)
 					vdisk_bio_set_hoq(bio);
 
 				if (!hbio)
-					hbio = tbio = bio;
+					hbio = bio;
 				else
-					tbio = tbio->bi_next = bio;
+					tbio->bi_next = bio;
+				tbio = bio;
 			}
 
 			bytes = min_t(unsigned int, len, PAGE_SIZE - off);

scst/src/scst_lib.c

@@ -16123,9 +16123,11 @@ static void __scst_update_latency_stats(struct scst_cmd *cmd,
 				stat->maxc = deltac;
 #endif
 		} else {
-			stat->min = stat->max = delta;
+			stat->max = delta;
+			stat->min = delta;
 #ifdef SCST_MEASURE_CLOCK_CYCLES
-			stat->minc = stat->maxc = deltac;
+			stat->maxc = deltac;
+			stat->minc = deltac;
 #endif
 		}
 		stat->sum += delta;