MINOR: peers: Move ack, switch and definition receive code to reduce the size of...

Implement three new functions to treat peer acks, switch and
definition messages extracting the code from the big swich-case
of the peer I/O handler to give more chances to this latter to be
readable.

May be backported as far as 1.5.

diff --git a/src/peers.c b/src/peers.c
index 2fb51d70fe00f4c04b41187d7f202373e200aa52..c9389e34807d6b785e601d79184399c4c15e15b2 100644 (file)
--- a/src/peers.c
+++ b/src/peers.c
@@ -1084,6 +1084,171 @@ static int peer_recv_updatemsg(struct appctx *appctx, struct peer *p, int updt,
        return 0;
 }
 
+/*
+ * Function used to parse a stick-table update acknowledgement message after it
+ * has been received by <p> peer with <msg_cur> as address of the pointer to the position in the
+ * receipt buffer with <msg_end> being the position of the end of the stick-table message.
+ * Update <msg_curr> accordingly to the peer protocol specs if no peer protocol error
+ * was encountered.
+ * Return 1 if succeeded, 0 if not with the appctx state st0 set to PEER_SESS_ST_ERRPROTO.
+ */
+static inline int peer_treat_ackmsg(struct appctx *appctx, struct peer *p,
+                                    char **msg_cur, char *msg_end)
+{
+       /* ack message */
+       uint32_t table_id ;
+       uint32_t update;
+       struct shared_table *st;
+
+       table_id = intdecode(msg_cur, msg_end);
+       if (!*msg_cur || (*msg_cur + sizeof(update) > msg_end)) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       memcpy(&update, *msg_cur, sizeof(update));
+       update = ntohl(update);
+
+       for (st = p->tables; st; st = st->next) {
+               if (st->local_id == table_id) {
+                       st->update = update;
+                       break;
+               }
+       }
+
+       return 1;
+}
+
+/*
+ * Function used to parse a stick-table switch message after it has been received
+ * by <p> peer with <msg_cur> as address of the pointer to the position in the
+ * receipt buffer with <msg_end> being the position of the end of the stick-table message.
+ * Update <msg_curr> accordingly to the peer protocol specs if no peer protocol error
+ * was encountered.
+ * Return 1 if succeeded, 0 if not with the appctx state st0 set to PEER_SESS_ST_ERRPROTO.
+ */
+static inline int peer_treat_switchmsg(struct appctx *appctx, struct peer *p,
+                                      char **msg_cur, char *msg_end)
+{
+       struct shared_table *st;
+       int table_id;
+
+       table_id = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       p->remote_table = NULL;
+       for (st = p->tables; st; st = st->next) {
+               if (st->remote_id == table_id) {
+                       p->remote_table = st;
+                       break;
+               }
+       }
+
+       return 1;
+}
+
+/*
+ * Function used to parse a stick-table definition message after it has been received
+ * by <p> peer with <msg_cur> as address of the pointer to the position in the
+ * receipt buffer with <msg_end> being the position of the end of the stick-table message.
+ * Update <msg_curr> accordingly to the peer protocol specs if no peer protocol error
+ * was encountered.
+ * <totl> is the length of the stick-table update message computed upon receipt.
+ * Return 1 if succeeded, 0 if not with the appctx state st0 set to PEER_SESS_ST_ERRPROTO.
+ */
+static inline int peer_treat_definemsg(struct appctx *appctx, struct peer *p,
+                                      char **msg_cur, char *msg_end, int totl)
+{
+       struct stream_interface *si = appctx->owner;
+       int table_id_len;
+       struct shared_table *st;
+       int table_type;
+       int table_keylen;
+       int table_id;
+       uint64_t table_data;
+
+       table_id = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       table_id_len = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       p->remote_table = NULL;
+       if (!table_id_len || (*msg_cur + table_id_len) >= msg_end) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       for (st = p->tables; st; st = st->next) {
+               /* Reset IDs */
+               if (st->remote_id == table_id)
+                       st->remote_id = 0;
+
+               if (!p->remote_table && (table_id_len == strlen(st->table->id)) &&
+                   (memcmp(st->table->id, *msg_cur, table_id_len) == 0))
+                       p->remote_table = st;
+       }
+
+       if (!p->remote_table)
+               goto ignore_msg;
+
+       *msg_cur += table_id_len;
+       if (*msg_cur >= msg_end) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       table_type = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       table_keylen = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       table_data = intdecode(msg_cur, msg_end);
+       if (!*msg_cur) {
+               /* malformed message */
+               appctx->st0 = PEER_SESS_ST_ERRPROTO;
+               return 0;
+       }
+
+       if (p->remote_table->table->type != table_type
+               || p->remote_table->table->key_size != table_keylen) {
+               p->remote_table = NULL;
+               goto ignore_msg;
+       }
+
+       p->remote_table->remote_data = table_data;
+       p->remote_table->remote_id = table_id;
+       return 1;
+
+ ignore_msg:
+       co_skip(si_oc(si), totl);
+       return 0;
+}
+
 /*
  * IO Handler to handle message exchance with a peer
  */
@@ -1541,105 +1706,12 @@ switchstate:
                                }
                                else if (msg_head[0] == PEER_MSG_CLASS_STICKTABLE) {
                                        if (msg_head[1] == PEER_MSG_STKT_DEFINE) {
-                                               int table_id_len;
-                                               struct shared_table *st;
-                                               int table_type;
-                                               int table_keylen;
-                                               int table_id;
-                                               uint64_t table_data;
-
-                                               table_id = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               table_id_len = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               curpeer->remote_table = NULL;
-                                               if (!table_id_len || (msg_cur + table_id_len) >= msg_end) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               for (st = curpeer->tables; st; st = st->next) {
-                                                       /* Reset IDs */
-                                                       if (st->remote_id == table_id)
-                                                               st->remote_id = 0;
-
-                                                       if (!curpeer->remote_table
-                                                           && (table_id_len == strlen(st->table->id))
-                                                           && (memcmp(st->table->id, msg_cur, table_id_len) == 0)) {
-                                                               curpeer->remote_table = st;
-                                                       }
-                                               }
-
-                                               if (!curpeer->remote_table) {
-                                                       goto ignore_msg;
-                                               }
-
-                                               msg_cur += table_id_len;
-                                               if (msg_cur >= msg_end) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               table_type = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               table_keylen = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               table_data = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
-                                                       goto switchstate;
-                                               }
-
-                                               if (curpeer->remote_table->table->type != table_type
-                                                   || curpeer->remote_table->table->key_size != table_keylen) {
-                                                       curpeer->remote_table = NULL;
-                                                       goto ignore_msg;
-                                               }
-
-                                               curpeer->remote_table->remote_data = table_data;
-                                               curpeer->remote_table->remote_id = table_id;
+                                               if (!peer_treat_definemsg(appctx, curpeer, &msg_cur, msg_end, totl))
+                                                   goto switchstate;
                                        }
                                        else if (msg_head[1] == PEER_MSG_STKT_SWITCH) {
-                                               struct shared_table *st;
-                                               int table_id;
-
-                                               table_id = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
+                                               if (!peer_treat_switchmsg(appctx, curpeer, &msg_cur, msg_end))
                                                        goto switchstate;
-                                               }
-                                               curpeer->remote_table = NULL;
-                                               for (st = curpeer->tables; st; st = st->next) {
-                                                       if (st->remote_id == table_id) {
-                                                               curpeer->remote_table = st;
-                                                               break;
-                                                       }
-                                               }
-
                                        }
                                        else if (msg_head[1] == PEER_MSG_STKT_UPDATE
                                                 || msg_head[1] == PEER_MSG_STKT_INCUPDATE
@@ -1655,26 +1727,8 @@ switchstate:
 
                                        }
                                        else if (msg_head[1] == PEER_MSG_STKT_ACK) {
-                                               /* ack message */
-                                               uint32_t table_id ;
-                                               uint32_t update;
-                                               struct shared_table *st;
-
-                                               table_id = intdecode(&msg_cur, msg_end);
-                                               if (!msg_cur || (msg_cur + sizeof(update) > msg_end)) {
-                                                       /* malformed message */
-                                                       appctx->st0 = PEER_SESS_ST_ERRPROTO;
+                                               if (!peer_treat_ackmsg(appctx, curpeer, &msg_cur, msg_end))
                                                        goto switchstate;
-                                               }
-                                               memcpy(&update, msg_cur, sizeof(update));
-                                               update = ntohl(update);
-
-                                               for (st = curpeer->tables; st; st = st->next) {
-                                                       if (st->local_id == table_id) {
-                                                               st->update = update;
-                                                               break;
-                                                       }
-                                               }
                                        }
                                }
                                else if (msg_head[0] == PEER_MSG_CLASS_RESERVED) {