MINOR: peers: move "hello" message treatment code to reduce the size of the I/O handler.

This patch implements three functions to read and parse the three
line of a "hello" peer protocol message so that to call them from the
peer I/O handler and reduce its size.

May be backported as far as 1.5.

diff --git a/src/peers.c b/src/peers.c
index 4a08dd5b62b0419ac1b1ff2a067a7ecfdc4bb901..02485545f0f08d212b2ec96a4889a7d0243afd80 100644 (file)
--- a/src/peers.c
+++ b/src/peers.c
@@ -199,6 +199,7 @@ enum {
 #define PEER_MINOR_VER        1
 #define PEER_DWNGRD_MINOR_VER 0
 
+size_t proto_len = strlen(PEER_SESSION_PROTO_NAME);
 struct peers *cfg_peers = NULL;
 static void peer_session_forceshutdown(struct appctx *appctx);
 
@@ -1808,6 +1809,113 @@ static inline int peer_send_msgs(struct appctx *appctx, struct peer *peer)
        return 1;
 }
 
+/*
+ * Read and parse a first line of a "hello" peer protocol message.
+ * Returns 0 if could not read a line, -1 if there was a read error or
+ * the line is malformed, 1 if succeeded.
+ */
+static inline int peer_getline_version(struct appctx *appctx,
+                                       unsigned int *maj_ver, unsigned int *min_ver)
+{
+       int reql;
+
+       reql = peer_getline(appctx);
+       if (!reql)
+               return 0;
+
+       if (reql < 0)
+               return -1;
+
+       /* test protocol */
+       if (strncmp(PEER_SESSION_PROTO_NAME " ", trash.area, proto_len + 1) != 0) {
+               appctx->st0 = PEER_SESS_ST_EXIT;
+               appctx->st1 = PEER_SESS_SC_ERRPROTO;
+               return -1;
+       }
+       if (peer_get_version(trash.area + proto_len + 1, maj_ver, min_ver) == -1 ||
+               *maj_ver != PEER_MAJOR_VER || *min_ver > PEER_MINOR_VER) {
+               appctx->st0 = PEER_SESS_ST_EXIT;
+               appctx->st1 = PEER_SESS_SC_ERRVERSION;
+               return -1;
+       }
+
+       return 1;
+}
+
+/*
+ * Read and parse a second line of a "hello" peer protocol message.
+ * Returns 0 if could not read a line, -1 if there was a read error or
+ * the line is malformed, 1 if succeeded.
+ */
+static inline int peer_getline_host(struct appctx *appctx)
+{
+       int reql;
+
+       reql = peer_getline(appctx);
+       if (!reql)
+               return 0;
+
+       if (reql < 0)
+               return -1;
+
+       /* test hostname match */
+       if (strcmp(localpeer, trash.area) != 0) {
+               appctx->st0 = PEER_SESS_ST_EXIT;
+               appctx->st1 = PEER_SESS_SC_ERRHOST;
+               return -1;
+       }
+
+       return 1;
+}
+
+/*
+ * Read and parse a last line of a "hello" peer protocol message.
+ * Returns 0 if could not read a character, -1 if there was a read error or
+ * the line is malformed, 1 if succeeded.
+ * Set <curpeer> accordingly (the remote peer sending the "hello" message).
+ */
+static inline int peer_getline_last(struct appctx *appctx, struct peer **curpeer)
+{
+       char *p;
+       int reql;
+       struct peer *peer;
+       struct stream_interface *si = appctx->owner;
+       struct stream *s = si_strm(si);
+       struct peers *peers = strm_fe(s)->parent;
+
+       reql = peer_getline(appctx);
+       if (!reql)
+               return 0;
+
+       if (reql < 0)
+               return -1;
+
+       /* parse line "<peer name> <pid> <relative_pid>" */
+       p = strchr(trash.area, ' ');
+       if (!p) {
+               appctx->st0 = PEER_SESS_ST_EXIT;
+               appctx->st1 = PEER_SESS_SC_ERRPROTO;
+               return -1;
+       }
+       *p = 0;
+
+       /* lookup known peer */
+       for (peer = peers->remote; peer; peer = peer->next) {
+               if (strcmp(peer->id, trash.area) == 0)
+                       break;
+       }
+
+       /* if unknown peer */
+       if (!peer) {
+               appctx->st0 = PEER_SESS_ST_EXIT;
+               appctx->st1 = PEER_SESS_SC_ERRPEER;
+               return -1;
+       }
+       *curpeer = peer;
+
+       return 1;
+}
+
 /*
  * IO Handler to handle message exchance with a peer
  */
@@ -1819,7 +1927,6 @@ static void peer_io_handler(struct appctx *appctx)
        struct peer *curpeer = NULL;
        int reql = 0;
        int repl = 0;
-       size_t proto_len = strlen(PEER_SESSION_PROTO_NAME);
        unsigned int maj_ver, min_ver;
        int prev_state;
 
@@ -1841,24 +1948,10 @@ switchstate:
                                /* fall through */
                        case PEER_SESS_ST_GETVERSION:
                                prev_state = appctx->st0;
-
-                               reql = peer_getline(appctx);
-                               if (!reql)
-                                       goto out;
-
-                               if (reql < 0)
-                                       goto switchstate;
-
-                               /* test protocol */
-                               if (strncmp(PEER_SESSION_PROTO_NAME " ", trash.area, proto_len + 1) != 0) {
-                                       appctx->st0 = PEER_SESS_ST_EXIT;
-                                       appctx->st1 = PEER_SESS_SC_ERRPROTO;
-                                       goto switchstate;
-                               }
-                               if (peer_get_version(trash.area + proto_len + 1, &maj_ver, &min_ver) == -1 ||
-                                   maj_ver != PEER_MAJOR_VER || min_ver > PEER_MINOR_VER) {
-                                       appctx->st0 = PEER_SESS_ST_EXIT;
-                                       appctx->st1 = PEER_SESS_SC_ERRVERSION;
+                               reql = peer_getline_version(appctx, &maj_ver, &min_ver);
+                               if (reql <= 0) {
+                                       if (!reql)
+                                               goto out;
                                        goto switchstate;
                                }
 
@@ -1866,54 +1959,21 @@ switchstate:
                                /* fall through */
                        case PEER_SESS_ST_GETHOST:
                                prev_state = appctx->st0;
-
-                               reql = peer_getline(appctx);
-                               if (!reql)
-                                       goto out;
-
-                               if (reql < 0)
-                                       goto switchstate;
-
-                               /* test hostname match */
-                               if (strcmp(localpeer, trash.area) != 0) {
-                                       appctx->st0 = PEER_SESS_ST_EXIT;
-                                       appctx->st1 = PEER_SESS_SC_ERRHOST;
+                               reql = peer_getline_host(appctx);
+                               if (reql <= 0) {
+                                       if (!reql)
+                                               goto out;
                                        goto switchstate;
                                }
 
                                appctx->st0 = PEER_SESS_ST_GETPEER;
                                /* fall through */
                        case PEER_SESS_ST_GETPEER: {
-                               char *p;
-
                                prev_state = appctx->st0;
-
-                               reql = peer_getline(appctx);
-                               if (!reql)
-                                       goto out;
-
-                               if (reql < 0)
-                                       goto switchstate;
-
-                               /* parse line "<peer name> <pid> <relative_pid>" */
-                               p = strchr(trash.area, ' ');
-                               if (!p) {
-                                       appctx->st0 = PEER_SESS_ST_EXIT;
-                                       appctx->st1 = PEER_SESS_SC_ERRPROTO;
-                                       goto switchstate;
-                               }
-                               *p = 0;
-
-                               /* lookup known peer */
-                               for (curpeer = curpeers->remote; curpeer; curpeer = curpeer->next) {
-                                       if (strcmp(curpeer->id, trash.area) == 0)
-                                               break;
-                               }
-
-                               /* if unknown peer */
-                               if (!curpeer) {
-                                       appctx->st0 = PEER_SESS_ST_EXIT;
-                                       appctx->st1 = PEER_SESS_SC_ERRPEER;
+                               reql = peer_getline_last(appctx, &curpeer);
+                               if (reql <= 0) {
+                                       if (!reql)
+                                               goto out;
                                        goto switchstate;
                                }