From: Sebastian Harl <sh@tokkee.org>
Date: Mon, 29 Dec 2014 15:53:44 +0000 (+0100)
Subject: proto: Let unmarshal functions return the number of bytes processed.
X-Git-Tag: sysdb-0.7.0~92
X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=d25f3c59b5cf5387acd4e6d1467ce9efffa40f9a;p=sysdb.git

proto: Let unmarshal functions return the number of bytes processed.

That's a more flexible and straight-forward interface allowing callers to not
care about the size of the expected data.
---

diff --git a/src/client/sock.c b/src/client/sock.c
index bed6fc0..0d734f3 100644
--- a/src/client/sock.c
+++ b/src/client/sock.c
@@ -306,12 +306,13 @@ sdb_client_recv(sdb_client_t *client,
 		if (rstatus == UINT32_MAX) {
 			const char *str = sdb_strbuf_string(buf) + data_offset;
 			size_t len = sdb_strbuf_len(buf) - data_offset;
+			ssize_t n;
 
 			/* retrieve status and data len */
 			assert(len >= 2 * sizeof(uint32_t));
-			rstatus = sdb_proto_unmarshal_int32(str, len);
-			rlen = sdb_proto_unmarshal_int32(str + sizeof(rstatus),
-					len - sizeof(rstatus));
+			n = sdb_proto_unmarshal_int32(str, len, &rstatus);
+			str += n; len -= (size_t)n;
+			sdb_proto_unmarshal_int32(str, len, &rlen);
 
 			if (! rlen)
 				break;
diff --git a/src/frontend/connection.c b/src/frontend/connection.c
index 14e5336..91a9710 100644
--- a/src/frontend/connection.c
+++ b/src/frontend/connection.c
@@ -357,7 +357,7 @@ command_init(sdb_conn_t *conn)
 	sdb_strbuf_clear(conn->errbuf);
 
 	if (sdb_proto_unmarshal_header(SDB_STRBUF_STR(conn->buf),
-				&conn->cmd, &conn->cmd_len))
+				&conn->cmd, &conn->cmd_len) < 0)
 		return -1;
 	sdb_strbuf_skip(conn->buf, 0, 2 * sizeof(uint32_t));
 
diff --git a/src/frontend/query.c b/src/frontend/query.c
index 933ca04..63ec226 100644
--- a/src/frontend/query.c
+++ b/src/frontend/query.c
@@ -119,7 +119,7 @@ int
 sdb_fe_fetch(sdb_conn_t *conn)
 {
 	char name[conn->cmd_len + 1];
-	int type;
+	uint32_t type;
 
 	if ((! conn) || (conn->cmd != SDB_CONNECTION_FETCH))
 		return -1;
@@ -132,24 +132,24 @@ sdb_fe_fetch(sdb_conn_t *conn)
 		return -1;
 	}
 
-	type = sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf));
+	sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf), &type);
 	strncpy(name, sdb_strbuf_string(conn->buf) + sizeof(uint32_t),
 			conn->cmd_len - sizeof(uint32_t));
 	name[sizeof(name) - 1] = '\0';
 	/* TODO: support other types besides hosts */
-	return sdb_fe_exec_fetch(conn, type, name, NULL, /* filter = */ NULL);
+	return sdb_fe_exec_fetch(conn, (int)type, name, NULL, /* filter = */ NULL);
 } /* sdb_fe_fetch */
 
 int
 sdb_fe_list(sdb_conn_t *conn)
 {
-	int type = SDB_HOST;
+	uint32_t type = SDB_HOST;
 
 	if ((! conn) || (conn->cmd != SDB_CONNECTION_LIST))
 		return -1;
 
 	if (conn->cmd_len == sizeof(uint32_t))
-		type = sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf));
+		sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf), &type);
 	else if (conn->cmd_len) {
 		sdb_log(SDB_LOG_ERR, "frontend: Invalid command length %d for "
 				"LIST command", conn->cmd_len);
@@ -157,7 +157,7 @@ sdb_fe_list(sdb_conn_t *conn)
 				conn->cmd_len);
 		return -1;
 	}
-	return sdb_fe_exec_list(conn, type, /* filter = */ NULL);
+	return sdb_fe_exec_list(conn, (int)type, /* filter = */ NULL);
 } /* sdb_fe_list */
 
 int
@@ -167,7 +167,7 @@ sdb_fe_lookup(sdb_conn_t *conn)
 	const char *matcher;
 	size_t matcher_len;
 
-	int type;
+	uint32_t type;
 	int status;
 
 	conn_matcher_t m_node = {
@@ -188,7 +188,7 @@ sdb_fe_lookup(sdb_conn_t *conn)
 				conn->cmd_len);
 		return -1;
 	}
-	type = sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf));
+	sdb_proto_unmarshal_int32(SDB_STRBUF_STR(conn->buf), &type);
 
 	matcher = sdb_strbuf_string(conn->buf) + sizeof(uint32_t);
 	matcher_len = conn->cmd_len - sizeof(uint32_t);
@@ -203,7 +203,7 @@ sdb_fe_lookup(sdb_conn_t *conn)
 		return -1;
 	}
 
-	node.type = type;
+	node.type = (int)type;
 	m_node.matcher = m;
 
 	/* run analyzer separately; parse_matcher is missing
@@ -220,7 +220,7 @@ sdb_fe_lookup(sdb_conn_t *conn)
 		status = -1;
 	}
 	else
-		status = sdb_fe_exec_lookup(conn, type, m, /* filter = */ NULL);
+		status = sdb_fe_exec_lookup(conn, (int)type, m, /* filter = */ NULL);
 	sdb_object_deref(SDB_OBJ(m));
 	return status;
 } /* sdb_fe_lookup */
diff --git a/src/include/utils/proto.h b/src/include/utils/proto.h
index fd842c1..a872dd5 100644
--- a/src/include/utils/proto.h
+++ b/src/include/utils/proto.h
@@ -133,19 +133,23 @@ sdb_proto_marshal_attribute(char *buf, size_t buf_len,
  * Read and decode a message header from the specified string.
  *
  * Returns:
- *  - 0 on success
+ *  - the number of bytes read on success
  *  - a negative value else
  */
-int
+ssize_t
 sdb_proto_unmarshal_header(const char *buf, size_t buf_len,
 		uint32_t *code, uint32_t *msg_len);
 
 /*
  * sdb_proto_unmarshal_int32:
  * Read and decode a 32-bit integer from the specified string.
+ *
+ * Returns:
+ *  - the number of bytes read on success
+ *  - a negative value else
  */
-uint32_t
-sdb_proto_unmarshal_int32(const char *buf, size_t buf_len);
+ssize_t
+sdb_proto_unmarshal_int32(const char *buf, size_t buf_len, uint32_t *v);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/src/tools/sysdb/command.c b/src/tools/sysdb/command.c
index 2706dd2..c809c1f 100644
--- a/src/tools/sysdb/command.c
+++ b/src/tools/sysdb/command.c
@@ -49,9 +49,9 @@
 static void
 log_printer(sdb_strbuf_t *buf)
 {
-	uint32_t prio = sdb_proto_unmarshal_int32(SDB_STRBUF_STR(buf));
+	uint32_t prio = 0;
 
-	if (prio == UINT32_MAX) {
+	if (sdb_proto_unmarshal_int32(SDB_STRBUF_STR(buf), &prio) < 0) {
 		sdb_log(SDB_LOG_WARNING, "Received a LOG message with invalid "
 				"or missing priority");
 		prio = (uint32_t)SDB_LOG_ERR;
diff --git a/src/utils/proto.c b/src/utils/proto.c
index cd4e050..9cdc216 100644
--- a/src/utils/proto.c
+++ b/src/utils/proto.c
@@ -379,36 +379,39 @@ sdb_proto_marshal_attribute(char *buf, size_t buf_len,
 	return len;
 } /* sdb_proto_marshal_attribute */
 
-int
+ssize_t
 sdb_proto_unmarshal_header(const char *buf, size_t buf_len,
 		uint32_t *code, uint32_t *msg_len)
 {
 	uint32_t tmp;
+	ssize_t n;
 
 	if (buf_len < 2 * sizeof(uint32_t))
 		return -1;
 
-	tmp = sdb_proto_unmarshal_int32(buf, buf_len);
+	n = sdb_proto_unmarshal_int32(buf, buf_len, &tmp);
 	if (code)
 		*code = tmp;
-	tmp = sdb_proto_unmarshal_int32(buf + sizeof(uint32_t),
-			buf_len - sizeof(uint32_t));
+	buf += n; buf_len -= n;
+	sdb_proto_unmarshal_int32(buf, buf_len, &tmp);
 	if (msg_len)
 		*msg_len = tmp;
-	return 0;
+	return 2 * sizeof(uint32_t);
 } /* sdb_proto_unmarshal_header */
 
-uint32_t
-sdb_proto_unmarshal_int32(const char *buf, size_t buf_len)
+ssize_t
+sdb_proto_unmarshal_int32(const char *buf, size_t buf_len, uint32_t *v)
 {
 	uint32_t n;
 
 	/* not enough data to read */
 	if (buf_len < sizeof(n))
-		return UINT32_MAX;
+		return -1;
 
 	memcpy(&n, buf, sizeof(n));
-	return ntohl(n);
+	if (v)
+		*v = ntohl(n);
+	return sizeof(n);
 } /* sdb_proto_unmarshal_int32 */
 
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */