iron out all extra compiler warnings

clang-9 on x86/64 has reported following warnings/errors:

 libubus-acl.c:123:2: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 libubus-io.c:108:18: error: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
 libubus-io.c:395:56: error: comparison of integers of different signs: 'ssize_t' (aka 'long') and 'size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
 libubus-req.c:441:4: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:119:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd_acl.c:152:5: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:348:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:352:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:357:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:362:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:367:3: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]
 ubusd_acl.c:447:16: error: comparison of integers of different signs: 'int' and '__size_t' (aka 'unsigned long') [-Werror,-Wsign-compare]
 ubusd_acl.c:502:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd.c:123:13: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd.c:170:15: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd.c:262:43: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd.c:287:30: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd_event.c:170:18: error: comparison of integers of different signs: 'int' and 'unsigned long' [-Werror,-Wsign-compare]
 ubusd_obj.c:71:2: error: comparison of integers of different signs: 'size_t' (aka 'unsigned long') and 'int' [-Werror,-Wsign-compare]

Signed-off-by: Petr Štetiar <ynezz@true.cz>

cli.c

@@ -47,7 +47,7 @@ static const char *format_type(void *priv, struct blob_attr *attr)
 		[BLOBMSG_TYPE_TABLE] = "\"Table\"",
 	};
 	const char *type = NULL;
-	int typeid;
+	size_t typeid;
 
 	if (blob_id(attr) != BLOBMSG_TYPE_INT32)
 		return NULL;
@@ -65,7 +65,7 @@ static void receive_list_result(struct ubus_context *ctx, struct ubus_object_dat
 {
 	struct blob_attr *cur;
 	char *s;
-	int rem;
+	size_t rem;
 
 	if (simple_output || !verbose) {
 		printf("%s\n", obj->path);
@@ -520,7 +520,7 @@ static int ubus_cli_monitor(struct ubus_context *ctx, int argc, char **argv)
 
 static int add_monitor_type(const char *type)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < ARRAY_SIZE(monitor_types); i++) {
 		if (!monitor_types[i] || strcmp(monitor_types[i], type) != 0)
@@ -575,9 +575,10 @@ int main(int argc, char **argv)
 {
 	const char *progname, *ubus_socket = NULL;
 	struct ubus_context *ctx;
-	char *cmd;
 	int ret = 0;
-	int i, ch;
+	char *cmd;
+	size_t i;
+	int ch;
 
 	progname = argv[0];
 

examples/server.c

@@ -84,7 +84,7 @@ static int test_hello(struct ubus_context *ctx, struct ubus_object *obj,
 {
 	struct hello_request *hreq;
 	struct blob_attr *tb[__HELLO_MAX];
-	const char *format = "%s received a message: %s";
+	const char format[] = "%s received a message: %s";
 	const char *msgstr = "(unknown)";
 
 	blobmsg_parse(hello_policy, ARRAY_SIZE(hello_policy), tb, blob_data(msg), blob_len(msg));
@@ -92,11 +92,12 @@ static int test_hello(struct ubus_context *ctx, struct ubus_object *obj,
 	if (tb[HELLO_MSG])
 		msgstr = blobmsg_data(tb[HELLO_MSG]);
 
-	hreq = calloc(1, sizeof(*hreq) + strlen(format) + strlen(obj->name) + strlen(msgstr) + 1);
+	size_t len = sizeof(*hreq) + sizeof(format) + strlen(obj->name) + strlen(msgstr) + 1;
+	hreq = calloc(1, len);
 	if (!hreq)
 		return UBUS_STATUS_UNKNOWN_ERROR;
 
-	sprintf(hreq->data, format, obj->name, msgstr);
+	snprintf(hreq->data, len, format, obj->name, msgstr);
 	ubus_defer_request(ctx, req, &hreq->req);
 	hreq->timeout.cb = test_hello_reply;
 	uloop_timeout_set(&hreq->timeout, 1000);

libubus-acl.c

@@ -102,7 +102,7 @@ static void acl_recv_cb(struct ubus_request *req,
 {
 	struct blob_attr *tb[__ACL_POLICY_MAX];
 	struct blob_attr *cur;
-	int rem;
+	size_t rem;
 
 	if (acl_blob) {
 		struct acl_object *p, *q;

libubus-io.c

@@ -78,7 +78,7 @@ static int writev_retry(int fd, struct iovec *iov, int iov_len, int sock_fd)
 	int len = 0;
 
 	do {
-		int cur_len;
+		ssize_t cur_len;
 
 		if (sock_fd < 0) {
 			msghdr.msg_control = NULL;
@@ -105,7 +105,7 @@ static int writev_retry(int fd, struct iovec *iov, int iov_len, int sock_fd)
 			sock_fd = -1;
 
 		len += cur_len;
-		while (cur_len >= iov->iov_len) {
+		while (cur_len >= (ssize_t) iov->iov_len) {
 			cur_len -= iov->iov_len;
 			iov_len--;
 			iov++;
@@ -392,7 +392,7 @@ int ubus_reconnect(struct ubus_context *ctx, const char *path)
 		goto out_close;
 
 	memcpy(buf, &hdr.data, sizeof(hdr.data));
-	if (read(ctx->sock.fd, blob_data(buf), blob_len(buf)) != blob_len(buf))
+	if (read(ctx->sock.fd, blob_data(buf), blob_len(buf)) != (ssize_t) blob_len(buf))
 		goto out_free;
 
 	ctx->local_id = hdr.hdr.peer;

libubus-req.c

@@ -428,7 +428,8 @@ static void ubus_process_notify_status(struct ubus_request *req, int id, struct
 	struct ubus_notify_request *nreq;
 	struct blob_attr **tb;
 	struct blob_attr *cur;
-	int rem, idx = 1;
+	size_t rem;
+	int idx = 1;
 	int ret = 0;
 
 	nreq = container_of(req, struct ubus_notify_request, req);

lua/ubus.c

@@ -52,11 +52,11 @@ static int
 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table);
 
 static int
-ubus_lua_parse_blob_array(lua_State *L, struct blob_attr *attr, int len, bool table)
+ubus_lua_parse_blob_array(lua_State *L, struct blob_attr *attr, size_t len, bool table)
 {
 	int rv;
 	int idx = 1;
-	int rem = len;
+	size_t rem = len;
 	struct blob_attr *pos;
 
 	lua_newtable(L);

ubusd.c

@@ -92,7 +92,7 @@ void ubus_msg_free(struct ubus_msg_buf *ub)
 	}
 }
 
-static int ubus_msg_writev(int fd, struct ubus_msg_buf *ub, int offset)
+static ssize_t ubus_msg_writev(int fd, struct ubus_msg_buf *ub, size_t offset)
 {
 	static struct iovec iov[2];
 	static struct {
@@ -112,7 +112,7 @@ static int ubus_msg_writev(int fd, struct ubus_msg_buf *ub, int offset)
 		.msg_controllen = sizeof(fd_buf),
 	};
 	struct ubus_msghdr hdr;
-	int ret;
+	ssize_t ret;
 
 	fd_buf.fd = ub->fd;
 	if (ub->fd < 0 || offset) {
@@ -156,7 +156,7 @@ static void ubus_msg_enqueue(struct ubus_client *cl, struct ubus_msg_buf *ub)
 /* takes the msgbuf reference */
 void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub)
 {
-	int written;
+	ssize_t written;
 
 	if (ub->hdr.type != UBUS_MSG_MONITOR)
 		ubusd_monitor_message(cl, ub, true);
@@ -167,7 +167,7 @@ void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub)
 		if (written < 0)
 			written = 0;
 
-		if (written >= ub->len + sizeof(ub->hdr))
+		if (written >= (ssize_t) (ub->len + sizeof(ub->hdr)))
 			return;
 
 		cl->txq_ofs = written;
@@ -232,7 +232,7 @@ static void client_cb(struct uloop_fd *sock, unsigned int events)
 
 	/* first try to tx more pending data */
 	while ((ub = ubus_msg_head(cl))) {
-		int written;
+		ssize_t written;
 
 		written = ubus_msg_writev(sock->fd, ub, cl->txq_ofs);
 		if (written < 0) {
@@ -259,7 +259,7 @@ static void client_cb(struct uloop_fd *sock, unsigned int events)
 		uloop_fd_add(sock, ULOOP_READ | ULOOP_EDGE_TRIGGER);
 
 retry:
-	if (!sock->eof && cl->pending_msg_offset < sizeof(cl->hdrbuf)) {
+	if (!sock->eof && cl->pending_msg_offset < (int) sizeof(cl->hdrbuf)) {
 		int offset = cl->pending_msg_offset;
 		int bytes;
 
@@ -284,7 +284,7 @@ retry:
 			cl->pending_msg_fd = fd_buf.fd;
 
 		cl->pending_msg_offset += bytes;
-		if (cl->pending_msg_offset < sizeof(cl->hdrbuf))
+		if (cl->pending_msg_offset < (int) sizeof(cl->hdrbuf))
 			goto out;
 
 		if (blob_pad_len(&cl->hdrbuf.data) > UBUS_MAX_MSGLEN)

ubusd_acl.c

@@ -116,7 +116,7 @@ ubusd_acl_check(struct ubus_client *cl, const char *obj,
 			if (!acl->partial)
 				continue;
 
-			if (match_len != strlen(key))
+			if (match_len != (int) strlen(key))
 				continue;
 		}
 
@@ -147,7 +147,7 @@ ubusd_acl_check(struct ubus_client *cl, const char *obj,
 		case UBUS_ACL_ACCESS:
 			if (acl->methods) {
 				struct blob_attr *cur;
-				int rem;
+				size_t rem;
 
 				blobmsg_for_each_attr(cur, acl->methods, rem)
 					if (blobmsg_type(cur) == BLOBMSG_TYPE_STRING)
@@ -332,7 +332,7 @@ static void
 ubusd_acl_file_add(struct ubusd_acl_file *file)
 {
 	struct blob_attr *tb[__ACL_MAX], *cur;
-	int rem;
+	size_t rem;
 
 	blobmsg_parse(acl_policy, __ACL_MAX, tb, blob_data(file->blob),
 		      blob_len(file->blob));
@@ -435,7 +435,7 @@ ubusd_acl_load(void)
 {
 	struct stat st;
 	glob_t gl;
-	int j;
+	size_t j;
 	const char *suffix = "/*.json";
 	char *path = alloca(strlen(ubusd_acl_dir) + strlen(suffix) + 1);
 
@@ -499,7 +499,7 @@ ubusd_reply_add(struct ubus_object *obj)
 			if (!acl->partial)
 				continue;
 
-			if (match_len != strlen(key))
+			if (match_len != (int) strlen(key))
 				continue;
 		}
 

ubusd_event.c

@@ -167,7 +167,7 @@ int ubusd_send_event(struct ubus_client *cl, const char *id,
 			if (!ev->partial)
 				continue;
 
-			if (match_len != strlen(key))
+			if (match_len != (int) strlen(key))
 				continue;
 		}
 

ubusd_obj.c

@@ -55,7 +55,7 @@ static struct ubus_object_type *ubus_create_obj_type(struct blob_attr *sig)
 {
 	struct ubus_object_type *type;
 	struct blob_attr *pos;
-	int rem;
+	size_t rem;
 
 	type = calloc(1, sizeof(*type));
 	if (!type)