X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fjsonrpc.c;h=705cef77ab09ea2184dfa8e546d13baf9b24abbc;hb=de5cdb90f7c02d22b0595c7dc311c5306291b02f;hp=cf2a497156334df3f5d883a8e2fe7afd31f93c71;hpb=f212909325be9bc7e296e1a32e2fc89694a0049f;p=sliver-openvswitch.git

diff --git a/lib/jsonrpc.c b/lib/jsonrpc.c
index cf2a49715..705cef77a 100644
--- a/lib/jsonrpc.c
+++ b/lib/jsonrpc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,18 +18,22 @@
 
 #include "jsonrpc.h"
 
+#include <assert.h>
 #include <errno.h>
 
 #include "byteq.h"
+#include "dynamic-string.h"
+#include "fatal-signal.h"
 #include "json.h"
 #include "list.h"
 #include "ofpbuf.h"
 #include "poll-loop.h"
-#include "queue.h"
+#include "reconnect.h"
 #include "stream.h"
-
-#define THIS_MODULE VLM_jsonrpc
+#include "timeval.h"
 #include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(jsonrpc);
 
 struct jsonrpc {
     struct stream *stream;
@@ -42,7 +46,7 @@ struct jsonrpc {
     struct jsonrpc_msg *received;
 
     /* Output. */
-    struct ovs_queue output;
+    struct list output;         /* Contains "struct ofpbuf"s. */
     size_t backlog;
 };
 
@@ -52,6 +56,24 @@ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 5);
 static void jsonrpc_received(struct jsonrpc *);
 static void jsonrpc_cleanup(struct jsonrpc *);
 
+/* This is just the same as stream_open() except that it uses the default
+ * JSONRPC ports if none is specified. */
+int
+jsonrpc_stream_open(const char *name, struct stream **streamp)
+{
+    return stream_open_with_default_ports(name, JSONRPC_TCP_PORT,
+                                          JSONRPC_SSL_PORT, streamp);
+}
+
+/* This is just the same as pstream_open() except that it uses the default
+ * JSONRPC ports if none is specified. */
+int
+jsonrpc_pstream_open(const char *name, struct pstream **pstreamp)
+{
+    return pstream_open_with_default_ports(name, JSONRPC_TCP_PORT,
+                                           JSONRPC_SSL_PORT, pstreamp);
+}
+
 struct jsonrpc *
 jsonrpc_open(struct stream *stream)
 {
@@ -63,7 +85,7 @@ jsonrpc_open(struct stream *stream)
     rpc->name = xstrdup(stream_get_name(stream));
     rpc->stream = stream;
     byteq_init(&rpc->input);
-    queue_init(&rpc->output);
+    list_init(&rpc->output);
 
     return rpc;
 }
@@ -85,8 +107,9 @@ jsonrpc_run(struct jsonrpc *rpc)
         return;
     }
 
-    while (!queue_is_empty(&rpc->output)) {
-        struct ofpbuf *buf = rpc->output.head;
+    stream_run(rpc->stream);
+    while (!list_is_empty(&rpc->output)) {
+        struct ofpbuf *buf = ofpbuf_from_list(rpc->output.next);
         int retval;
 
         retval = stream_send(rpc->stream, buf->data, buf->size);
@@ -94,7 +117,8 @@ jsonrpc_run(struct jsonrpc *rpc)
             rpc->backlog -= retval;
             ofpbuf_pull(buf, retval);
             if (!buf->size) {
-                ofpbuf_delete(queue_pop_head(&rpc->output));
+                list_remove(&buf->list_node);
+                ofpbuf_delete(buf);
             }
         } else {
             if (retval != -EAGAIN) {
@@ -110,11 +134,20 @@ jsonrpc_run(struct jsonrpc *rpc)
 void
 jsonrpc_wait(struct jsonrpc *rpc)
 {
-    if (!rpc->status && !queue_is_empty(&rpc->output)) {
-        stream_send_wait(rpc->stream);
+    if (!rpc->status) {
+        stream_run_wait(rpc->stream);
+        if (!list_is_empty(&rpc->output)) {
+            stream_send_wait(rpc->stream);
+        }
     }
 }
 
+/*
+ * Possible status values:
+ * - 0: no error yet
+ * - >0: errno value
+ * - EOF: end of file (remote end closed connection; not necessarily an error)
+ */
 int
 jsonrpc_get_status(const struct jsonrpc *rpc)
 {
@@ -133,6 +166,38 @@ jsonrpc_get_name(const struct jsonrpc *rpc)
     return rpc->name;
 }
 
+static void
+jsonrpc_log_msg(const struct jsonrpc *rpc, const char *title,
+                const struct jsonrpc_msg *msg)
+{
+    if (VLOG_IS_DBG_ENABLED()) {
+        struct ds s = DS_EMPTY_INITIALIZER;
+        if (msg->method) {
+            ds_put_format(&s, ", method=\"%s\"", msg->method);
+        }
+        if (msg->params) {
+            ds_put_cstr(&s, ", params=");
+            json_to_ds(msg->params, 0, &s);
+        }
+        if (msg->result) {
+            ds_put_cstr(&s, ", result=");
+            json_to_ds(msg->result, 0, &s);
+        }
+        if (msg->error) {
+            ds_put_cstr(&s, ", error=");
+            json_to_ds(msg->error, 0, &s);
+        }
+        if (msg->id) {
+            ds_put_cstr(&s, ", id=");
+            json_to_ds(msg->id, 0, &s);
+        }
+        VLOG_DBG("%s: %s %s%s", rpc->name, title,
+                 jsonrpc_msg_type_to_string(msg->type), ds_cstr(&s));
+        ds_destroy(&s);
+    }
+}
+
+/* Always takes ownership of 'msg', regardless of success. */
 int
 jsonrpc_send(struct jsonrpc *rpc, struct jsonrpc_msg *msg)
 {
@@ -146,6 +211,8 @@ jsonrpc_send(struct jsonrpc *rpc, struct jsonrpc_msg *msg)
         return rpc->status;
     }
 
+    jsonrpc_log_msg(rpc, "send", msg);
+
     json = jsonrpc_msg_to_json(msg);
     s = json_to_string(json, 0);
     length = strlen(s);
@@ -154,10 +221,10 @@ jsonrpc_send(struct jsonrpc *rpc, struct jsonrpc_msg *msg)
     buf = xmalloc(sizeof *buf);
     ofpbuf_use(buf, s, length);
     buf->size = length;
-    queue_push_tail(&rpc->output, buf);
+    list_push_back(&rpc->output, &buf->list_node);
     rpc->backlog += length;
 
-    if (rpc->output.n == 1) {
+    if (rpc->backlog == length) {
         jsonrpc_run(rpc);
     }
     return rpc->status;
@@ -188,7 +255,6 @@ jsonrpc_recv(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
                     return rpc->status;
                 }
             } else if (retval == 0) {
-                VLOG_INFO_RL(&rl, "%s: connection closed", rpc->name);
                 jsonrpc_error(rpc, EOF);
                 return EOF;
             }
@@ -206,6 +272,12 @@ jsonrpc_recv(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
             if (json_parser_is_done(rpc->parser)) {
                 jsonrpc_received(rpc);
                 if (rpc->status) {
+                    const struct byteq *q = &rpc->input;
+                    if (q->head <= BYTEQ_SIZE) {
+                        stream_report_content(q->buffer, q->head,
+                                              STREAM_JSONRPC,
+                                              THIS_MODULE, rpc->name);
+                    }
                     return rpc->status;
                 }
             }
@@ -221,28 +293,33 @@ void
 jsonrpc_recv_wait(struct jsonrpc *rpc)
 {
     if (rpc->status || rpc->received || !byteq_is_empty(&rpc->input)) {
-        poll_immediate_wake();
+        (poll_immediate_wake)(rpc->name);
     } else {
         stream_recv_wait(rpc->stream);
     }
 }
 
+/* Always takes ownership of 'msg', regardless of success. */
 int
 jsonrpc_send_block(struct jsonrpc *rpc, struct jsonrpc_msg *msg)
 {
     int error;
 
+    fatal_signal_run();
+
     error = jsonrpc_send(rpc, msg);
     if (error) {
         return error;
     }
 
-    while (!queue_is_empty(&rpc->output) && !rpc->status) {
+    for (;;) {
         jsonrpc_run(rpc);
+        if (list_is_empty(&rpc->output) || rpc->status) {
+            return rpc->status;
+        }
         jsonrpc_wait(rpc);
         poll_block();
     }
-    return rpc->status;
 }
 
 int
@@ -251,6 +328,7 @@ jsonrpc_recv_block(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
     for (;;) {
         int error = jsonrpc_recv(rpc, msgp);
         if (error != EAGAIN) {
+            fatal_signal_run();
             return error;
         }
 
@@ -261,6 +339,33 @@ jsonrpc_recv_block(struct jsonrpc *rpc, struct jsonrpc_msg **msgp)
     }
 }
 
+/* Always takes ownership of 'request', regardless of success. */
+int
+jsonrpc_transact_block(struct jsonrpc *rpc, struct jsonrpc_msg *request,
+                       struct jsonrpc_msg **replyp)
+{
+    struct jsonrpc_msg *reply = NULL;
+    struct json *id;
+    int error;
+
+    id = json_clone(request->id);
+    error = jsonrpc_send_block(rpc, request);
+    if (!error) {
+        for (;;) {
+            error = jsonrpc_recv_block(rpc, &reply);
+            if (error
+                || (reply->type == JSONRPC_REPLY
+                    && json_equal(id, reply->id))) {
+                break;
+            }
+            jsonrpc_msg_destroy(reply);
+        }
+    }
+    *replyp = error ? NULL : reply;
+    json_destroy(id);
+    return error;
+}
+
 static void
 jsonrpc_received(struct jsonrpc *rpc)
 {
@@ -287,6 +392,7 @@ jsonrpc_received(struct jsonrpc *rpc)
         return;
     }
 
+    jsonrpc_log_msg(rpc, "received", msg);
     rpc->received = msg;
 }
 
@@ -312,7 +418,7 @@ jsonrpc_cleanup(struct jsonrpc *rpc)
     jsonrpc_msg_destroy(rpc->received);
     rpc->received = NULL;
 
-    queue_clear(&rpc->output);
+    ofpbuf_list_delete(&rpc->output);
     rpc->backlog = 0;
 }
 
@@ -339,10 +445,14 @@ jsonrpc_create_id(void)
 }
 
 struct jsonrpc_msg *
-jsonrpc_create_request(const char *method, struct json *params)
+jsonrpc_create_request(const char *method, struct json *params,
+                       struct json **idp)
 {
-    return jsonrpc_create(JSONRPC_REQUEST, method, params, NULL, NULL,
-                           jsonrpc_create_id());
+    struct json *id = jsonrpc_create_id();
+    if (idp) {
+        *idp = json_clone(id);
+    }
+    return jsonrpc_create(JSONRPC_REQUEST, method, params, NULL, NULL, id);
 }
 
 struct jsonrpc_msg *
@@ -553,3 +663,320 @@ jsonrpc_msg_to_json(struct jsonrpc_msg *m)
 
     return json;
 }
+
+/* A JSON-RPC session with reconnection. */
+
+struct jsonrpc_session {
+    struct reconnect *reconnect;
+    struct jsonrpc *rpc;
+    struct stream *stream;
+    struct pstream *pstream;
+    unsigned int seqno;
+};
+
+/* Creates and returns a jsonrpc_session to 'name', which should be a string
+ * acceptable to stream_open() or pstream_open().
+ *
+ * If 'name' is an active connection method, e.g. "tcp:127.1.2.3", the new
+ * jsonrpc_session connects and reconnects, with back-off, to 'name'.
+ *
+ * If 'name' is a passive connection method, e.g. "ptcp:", the new
+ * jsonrpc_session listens for connections to 'name'.  It maintains at most one
+ * connection at any given time.  Any new connection causes the previous one
+ * (if any) to be dropped. */
+struct jsonrpc_session *
+jsonrpc_session_open(const char *name)
+{
+    struct jsonrpc_session *s;
+
+    s = xmalloc(sizeof *s);
+    s->reconnect = reconnect_create(time_msec());
+    reconnect_set_name(s->reconnect, name);
+    reconnect_enable(s->reconnect, time_msec());
+    s->rpc = NULL;
+    s->stream = NULL;
+    s->pstream = NULL;
+    s->seqno = 0;
+
+    if (!pstream_verify_name(name)) {
+        reconnect_set_passive(s->reconnect, true, time_msec());
+    }
+
+    return s;
+}
+
+/* Creates and returns a jsonrpc_session that is initially connected to
+ * 'jsonrpc'.  If the connection is dropped, it will not be reconnected.
+ *
+ * On the assumption that such connections are likely to be short-lived
+ * (e.g. from ovs-vsctl), informational logging for them is suppressed. */
+struct jsonrpc_session *
+jsonrpc_session_open_unreliably(struct jsonrpc *jsonrpc)
+{
+    struct jsonrpc_session *s;
+
+    s = xmalloc(sizeof *s);
+    s->reconnect = reconnect_create(time_msec());
+    reconnect_set_quiet(s->reconnect, true);
+    reconnect_set_name(s->reconnect, jsonrpc_get_name(jsonrpc));
+    reconnect_set_max_tries(s->reconnect, 0);
+    reconnect_connected(s->reconnect, time_msec());
+    s->rpc = jsonrpc;
+    s->stream = NULL;
+    s->pstream = NULL;
+    s->seqno = 0;
+
+    return s;
+}
+
+void
+jsonrpc_session_close(struct jsonrpc_session *s)
+{
+    if (s) {
+        jsonrpc_close(s->rpc);
+        reconnect_destroy(s->reconnect);
+        stream_close(s->stream);
+        pstream_close(s->pstream);
+        free(s);
+    }
+}
+
+static void
+jsonrpc_session_disconnect(struct jsonrpc_session *s)
+{
+    if (s->rpc) {
+        jsonrpc_error(s->rpc, EOF);
+        jsonrpc_close(s->rpc);
+        s->rpc = NULL;
+        s->seqno++;
+    } else if (s->stream) {
+        stream_close(s->stream);
+        s->stream = NULL;
+        s->seqno++;
+    }
+}
+
+static void
+jsonrpc_session_connect(struct jsonrpc_session *s)
+{
+    const char *name = reconnect_get_name(s->reconnect);
+    int error;
+
+    jsonrpc_session_disconnect(s);
+    if (!reconnect_is_passive(s->reconnect)) {
+        error = jsonrpc_stream_open(name, &s->stream);
+        if (!error) {
+            reconnect_connecting(s->reconnect, time_msec());
+        }
+    } else {
+        error = s->pstream ? 0 : jsonrpc_pstream_open(name, &s->pstream);
+        if (!error) {
+            reconnect_listening(s->reconnect, time_msec());
+        }
+    }
+
+    if (error) {
+        reconnect_connect_failed(s->reconnect, time_msec(), error);
+    }
+    s->seqno++;
+}
+
+void
+jsonrpc_session_run(struct jsonrpc_session *s)
+{
+    if (s->pstream) {
+        struct stream *stream;
+        int error;
+
+        error = pstream_accept(s->pstream, &stream);
+        if (!error) {
+            if (s->rpc || s->stream) {
+                VLOG_INFO_RL(&rl,
+                             "%s: new connection replacing active connection",
+                             reconnect_get_name(s->reconnect));
+                jsonrpc_session_disconnect(s);
+            }
+            reconnect_connected(s->reconnect, time_msec());
+            s->rpc = jsonrpc_open(stream);
+        } else if (error != EAGAIN) {
+            reconnect_listen_error(s->reconnect, time_msec(), error);
+            pstream_close(s->pstream);
+            s->pstream = NULL;
+        }
+    }
+
+    if (s->rpc) {
+        int error;
+
+        jsonrpc_run(s->rpc);
+        error = jsonrpc_get_status(s->rpc);
+        if (error) {
+            reconnect_disconnected(s->reconnect, time_msec(), error);
+            jsonrpc_session_disconnect(s);
+        }
+    } else if (s->stream) {
+        int error;
+
+        stream_run(s->stream);
+        error = stream_connect(s->stream);
+        if (!error) {
+            reconnect_connected(s->reconnect, time_msec());
+            s->rpc = jsonrpc_open(s->stream);
+            s->stream = NULL;
+        } else if (error != EAGAIN) {
+            reconnect_connect_failed(s->reconnect, time_msec(), error);
+            stream_close(s->stream);
+            s->stream = NULL;
+        }
+    }
+
+    switch (reconnect_run(s->reconnect, time_msec())) {
+    case RECONNECT_CONNECT:
+        jsonrpc_session_connect(s);
+        break;
+
+    case RECONNECT_DISCONNECT:
+        reconnect_disconnected(s->reconnect, time_msec(), 0);
+        jsonrpc_session_disconnect(s);
+        break;
+
+    case RECONNECT_PROBE:
+        if (s->rpc) {
+            struct json *params;
+            struct jsonrpc_msg *request;
+
+            params = json_array_create_empty();
+            request = jsonrpc_create_request("echo", params, NULL);
+            json_destroy(request->id);
+            request->id = json_string_create("echo");
+            jsonrpc_send(s->rpc, request);
+        }
+        break;
+    }
+}
+
+void
+jsonrpc_session_wait(struct jsonrpc_session *s)
+{
+    if (s->rpc) {
+        jsonrpc_wait(s->rpc);
+    } else if (s->stream) {
+        stream_run_wait(s->stream);
+        stream_connect_wait(s->stream);
+    }
+    if (s->pstream) {
+        pstream_wait(s->pstream);
+    }
+    reconnect_wait(s->reconnect, time_msec());
+}
+
+size_t
+jsonrpc_session_get_backlog(const struct jsonrpc_session *s)
+{
+    return s->rpc ? jsonrpc_get_backlog(s->rpc) : 0;
+}
+
+/* Always returns a pointer to a valid C string, assuming 's' was initialized
+ * correctly. */
+const char *
+jsonrpc_session_get_name(const struct jsonrpc_session *s)
+{
+    return reconnect_get_name(s->reconnect);
+}
+
+/* Always takes ownership of 'msg', regardless of success. */
+int
+jsonrpc_session_send(struct jsonrpc_session *s, struct jsonrpc_msg *msg)
+{
+    if (s->rpc) {
+        return jsonrpc_send(s->rpc, msg);
+    } else {
+        jsonrpc_msg_destroy(msg);
+        return ENOTCONN;
+    }
+}
+
+struct jsonrpc_msg *
+jsonrpc_session_recv(struct jsonrpc_session *s)
+{
+    if (s->rpc) {
+        struct jsonrpc_msg *msg;
+        jsonrpc_recv(s->rpc, &msg);
+        if (msg) {
+            reconnect_received(s->reconnect, time_msec());
+            if (msg->type == JSONRPC_REQUEST && !strcmp(msg->method, "echo")) {
+                /* Echo request.  Send reply. */
+                struct jsonrpc_msg *reply;
+
+                reply = jsonrpc_create_reply(json_clone(msg->params), msg->id);
+                jsonrpc_session_send(s, reply);
+            } else if (msg->type == JSONRPC_REPLY
+                       && msg->id && msg->id->type == JSON_STRING
+                       && !strcmp(msg->id->u.string, "echo")) {
+                /* It's a reply to our echo request.  Suppress it. */
+            } else {
+                return msg;
+            }
+            jsonrpc_msg_destroy(msg);
+        }
+    }
+    return NULL;
+}
+
+void
+jsonrpc_session_recv_wait(struct jsonrpc_session *s)
+{
+    if (s->rpc) {
+        jsonrpc_recv_wait(s->rpc);
+    }
+}
+
+bool
+jsonrpc_session_is_alive(const struct jsonrpc_session *s)
+{
+    return s->rpc || s->stream || reconnect_get_max_tries(s->reconnect);
+}
+
+bool
+jsonrpc_session_is_connected(const struct jsonrpc_session *s)
+{
+    return s->rpc != NULL;
+}
+
+unsigned int
+jsonrpc_session_get_seqno(const struct jsonrpc_session *s)
+{
+    return s->seqno;
+}
+
+int
+jsonrpc_session_get_status(const struct jsonrpc_session *s)
+{
+    return s && s->rpc ? jsonrpc_get_status(s->rpc) : 0;
+}
+
+void
+jsonrpc_session_get_reconnect_stats(const struct jsonrpc_session *s,
+                                    struct reconnect_stats *stats)
+{
+    reconnect_get_stats(s->reconnect, time_msec(), stats);
+}
+
+void
+jsonrpc_session_force_reconnect(struct jsonrpc_session *s)
+{
+    reconnect_force_reconnect(s->reconnect, time_msec());
+}
+
+void
+jsonrpc_session_set_max_backoff(struct jsonrpc_session *s, int max_backoff)
+{
+    reconnect_set_backoff(s->reconnect, 0, max_backoff);
+}
+
+void
+jsonrpc_session_set_probe_interval(struct jsonrpc_session *s,
+                                   int probe_interval)
+{
+    reconnect_set_probe_interval(s->reconnect, probe_interval);
+}