diff options
-rw-r--r-- | .gitignore | 2 | ||||
-rw-r--r-- | Makefile.am | 2 | ||||
-rw-r--r-- | src/include.am | 1 | ||||
-rw-r--r-- | src/lib/dispatch/.may_include | 9 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch.h | 114 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_cfg.c | 138 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_cfg.h | 39 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_cfg_st.h | 25 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_core.c | 234 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_new.c | 170 | ||||
-rw-r--r-- | src/lib/dispatch/dispatch_st.h | 108 | ||||
-rw-r--r-- | src/lib/dispatch/include.am | 23 | ||||
-rw-r--r-- | src/lib/dispatch/msgtypes.h | 80 | ||||
-rw-r--r-- | src/test/include.am | 1 | ||||
-rw-r--r-- | src/test/test.c | 1 | ||||
-rw-r--r-- | src/test/test.h | 1 | ||||
-rw-r--r-- | src/test/test_dispatch.c | 181 |
17 files changed, 1129 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore index 6a49285b8a..f4f6dacbb0 100644 --- a/.gitignore +++ b/.gitignore @@ -168,6 +168,8 @@ uptime-*.json /src/lib/libtor-crypt-ops-testing.a /src/lib/libtor-ctime.a /src/lib/libtor-ctime-testing.a +/src/lib/libtor-dispatch.a +/src/lib/libtor-dispatch-testing.a /src/lib/libtor-encoding.a /src/lib/libtor-encoding-testing.a /src/lib/libtor-evloop.a diff --git a/Makefile.am b/Makefile.am index a5086b3035..36d9725f38 100644 --- a/Makefile.am +++ b/Makefile.am @@ -41,6 +41,7 @@ TOR_UTIL_LIBS = \ src/lib/libtor-geoip.a \ src/lib/libtor-process.a \ src/lib/libtor-buf.a \ + src/lib/libtor-dispatch.a \ src/lib/libtor-time.a \ src/lib/libtor-fs.a \ src/lib/libtor-encoding.a \ @@ -72,6 +73,7 @@ TOR_UTIL_TESTING_LIBS = \ src/lib/libtor-geoip-testing.a \ src/lib/libtor-process-testing.a \ src/lib/libtor-buf-testing.a \ + src/lib/libtor-dispatch-testing.a \ src/lib/libtor-time-testing.a \ src/lib/libtor-fs-testing.a \ src/lib/libtor-encoding-testing.a \ diff --git a/src/include.am b/src/include.am index 9070a69a03..c6c351c806 100644 --- a/src/include.am +++ b/src/include.am @@ -8,6 +8,7 @@ include src/lib/compress/include.am include src/lib/container/include.am include src/lib/crypt_ops/include.am include src/lib/defs/include.am +include src/lib/dispatch/include.am include src/lib/encoding/include.am include src/lib/evloop/include.am include src/lib/fdio/include.am diff --git a/src/lib/dispatch/.may_include b/src/lib/dispatch/.may_include new file mode 100644 index 0000000000..9b5373907e --- /dev/null +++ b/src/lib/dispatch/.may_include @@ -0,0 +1,9 @@ +orconfig.h + +ext/tor_queue.h + +lib/container/*.h +lib/dispatch/*.h +lib/intmath/*.h +lib/log/*.h +lib/malloc/*.h diff --git a/src/lib/dispatch/dispatch.h b/src/lib/dispatch/dispatch.h new file mode 100644 index 0000000000..8e62e8f168 --- /dev/null +++ b/src/lib/dispatch/dispatch.h @@ -0,0 +1,114 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_DISPATCH_H +#define TOR_DISPATCH_H + +#include "lib/dispatch/msgtypes.h" + +/** + * \file dispatch.h + * \brief Low-level APIs for message-passing system. + * + * This module implements message dispatch based on a set of short integer + * identifiers. For a higher-level interface, see pubsub.h. + * + * Each message is represented as a generic msg_t object, and is discriminated + * by its message_id_t. Messages are delivered by a dispatch_t object, which + * delivers each message to its recipients by a configured "channel". + * + * A "channel" is a means of delivering messages. Every message_id_t must + * be associated with exactly one channel, identified by channel_id_t. + * When a channel receives messages, a callback is invoked to either process + * the messages immediately, or to cause them to be processed later. + * + * Every message_id_t has zero or more associated receiver functions set up in + * the dispatch_t object. Once the dispatch_t object is created, receivers + * can be enabled or disabled [TODO], but not added or removed. + * + * Every message_id_t has an associated datatype, identified by a + * msg_type_id_t. These datatypes can be associated with functions to + * (for example) free them, or format them for debugging. + * + * To setup a dispatch_t object, first create a dispatch_cfg_t object, and + * configure messages with their types, channels, and receivers. Then, use + * dispatch_new() with that dispatch_cfg_t to create the dispatch_t object. + * + * (We use a two-phase contruction procedure here to enable better static + * reasoning about publish/subscribe relationships.) + * + * Once you have a dispatch_t, you can queue messages on it with + * dispatch_send*(), and cause those messages to be delivered with + * dispatch_flush(). + **/ + +/** + * A "dispatcher" is the highest-level object; it handles making sure that + * messages are received and delivered properly. Only the mainloop + * should handle this type directly. + */ +typedef struct dispatch_t dispatch_t; + +struct dispatch_cfg_t; + +dispatch_t *dispatch_new(const struct dispatch_cfg_t *cfg); + +/** + * Free a dispatcher. Tor does this at exit. + */ +#define dispatch_free(d) \ + FREE_AND_NULL(dispatch_t, dispatch_free_, (d)) + +void dispatch_free_(dispatch_t *); + +int dispatch_send(dispatch_t *d, + subsys_id_t sender, + channel_id_t channel, + message_id_t msg, + msg_type_id_t type, + msg_aux_data_t auxdata); + +int dispatch_send_msg(dispatch_t *d, msg_t *m); + +int dispatch_send_msg_unchecked(dispatch_t *d, msg_t *m); + +/* Flush up to <b>max_msgs</b> currently pending messages from the + * dispatcher. Messages that are not pending when this function are + * called, are not flushed by this call. Return 0 on success, -1 on + * unrecoverable error. + */ +int dispatch_flush(dispatch_t *, channel_id_t chan, int max_msgs); + +/** + * Function callback type used to alert some other module when a channel's + * queue changes from empty to nonempty. + * + * Ex 1: To cause messages to be processed immediately on-stack, this callback + * should invoke dispatch_flush() directly. + * + * Ex 2: To cause messages to be processed very soon, from the event queue, + * this callback should schedule an event callback to run dispatch_flush(). + * + * Ex 3: To cause messages to be processed periodically, this function should + * do nothing, and a periodic event should invoke dispatch_flush(). + **/ +typedef void (*dispatch_alertfn_t)(struct dispatch_t *, + channel_id_t, void *); + +int dispatch_set_alert_fn(dispatch_t *d, channel_id_t chan, + dispatch_alertfn_t fn, void *userdata); + +#define dispatch_free_msg(d,msg) \ + STMT_BEGIN { \ + msg_t **msg_tmp_ptr__ = &(msg); \ + dispatch_free_msg_((d), *msg_tmp_ptr__); \ + *msg_tmp_ptr__= NULL; \ + } STMT_END +void dispatch_free_msg_(const dispatch_t *d, msg_t *msg); + +char *dispatch_fmt_msg_data(const dispatch_t *d, const msg_t *msg); + +#endif diff --git a/src/lib/dispatch/dispatch_cfg.c b/src/lib/dispatch/dispatch_cfg.c new file mode 100644 index 0000000000..26e37f4694 --- /dev/null +++ b/src/lib/dispatch/dispatch_cfg.c @@ -0,0 +1,138 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file dispatch_cfg.c + * \brief Create and configure a dispatch_cfg_t. + * + * A dispatch_cfg_t object is used to configure a set of messages and + * associated information before creating a dispatch_t. + */ + +#define DISPATCH_PRIVATE + +#include "orconfig.h" +#include "lib/dispatch/dispatch_cfg.h" +#include "lib/dispatch/dispatch_cfg_st.h" +#include "lib/dispatch/dispatch.h" +#include "lib/dispatch/dispatch_st.h" + +#include "lib/container/smartlist.h" +#include "lib/malloc/malloc.h" + +/** + * Create and return a new dispatch_cfg_t. + **/ +dispatch_cfg_t * +dcfg_new(void) +{ + dispatch_cfg_t *cfg = tor_malloc(sizeof(dispatch_cfg_t)); + cfg->type_by_msg = smartlist_new(); + cfg->chan_by_msg = smartlist_new(); + cfg->fns_by_type = smartlist_new(); + cfg->recv_by_msg = smartlist_new(); + return cfg; +} + +/** DOCDOC */ +#define ID_TO_VOID(id) ((void*)(uintptr_t)(id)) + +/** + * Associate a message with a datatype. Return 0 on success, -1 if a + * different type was previously associated with the message ID. + **/ +int +dcfg_msg_set_type(dispatch_cfg_t *cfg, message_id_t msg, + msg_type_id_t type) +{ + smartlist_grow(cfg->type_by_msg, msg+1); + void *oldval = smartlist_get(cfg->type_by_msg, msg); + if (oldval != NULL && oldval != ID_TO_VOID(type)) { + return -1; + } + smartlist_set(cfg->type_by_msg, msg, ID_TO_VOID(type)); + return 0; +} + +/** + * Associate a message with a channel. Return 0 on success, -1 if a + * different channel was previously associated with the message ID. + **/ +int +dcfg_msg_set_chan(dispatch_cfg_t *cfg, message_id_t msg, + channel_id_t chan) +{ + smartlist_grow(cfg->chan_by_msg, msg+1); + void *oldval = smartlist_get(cfg->chan_by_msg, msg); + if (oldval != NULL && oldval != ID_TO_VOID(chan)) { + return -1; + } + smartlist_set(cfg->chan_by_msg, msg, ID_TO_VOID(chan)); + return 0; +} + +/** + * Associate a set of functions with a datatype. Return 0 on success, -1 if + * different functions were previously associated with the type. + **/ +int +dcfg_type_set_fns(dispatch_cfg_t *cfg, msg_type_id_t type, + const dispatch_typefns_t *fns) +{ + smartlist_grow(cfg->fns_by_type, type+1); + dispatch_typefns_t *oldfns = smartlist_get(cfg->fns_by_type, type); + if (oldfns && (oldfns->free_fn != fns->free_fn || + oldfns->fmt_fn != fns->fmt_fn)) + return -1; + smartlist_set(cfg->fns_by_type, type, (dispatch_typefns_t *) fns); + return 0; +} + +/** + * Associate a receiver with a message ID. Multiple receivers may be + * associated with a single messasge ID. + * + * Return 0 on success, on failure. + **/ +int +dcfg_add_recv(dispatch_cfg_t *cfg, message_id_t msg, + subsys_id_t sys, recv_fn_t fn) +{ + smartlist_grow(cfg->recv_by_msg, msg+1); + smartlist_t *receivers = smartlist_get(cfg->recv_by_msg, msg); + if (!receivers) { + receivers = smartlist_new(); + smartlist_set(cfg->recv_by_msg, msg, receivers); + } + + dispatch_rcv_t *rcv = tor_malloc(sizeof(dispatch_rcv_t)); + rcv->sys = sys; + rcv->enabled = true; + rcv->fn = fn; + smartlist_add(receivers, (void*)rcv); + return 0; +} + +/** Helper: release all storage held by <b>cfg</b>. */ +void +dcfg_free_(dispatch_cfg_t *cfg) +{ + if (!cfg) + return; + + smartlist_free(cfg->type_by_msg); + smartlist_free(cfg->chan_by_msg); + smartlist_free(cfg->fns_by_type); + SMARTLIST_FOREACH_BEGIN(cfg->recv_by_msg, smartlist_t *, receivers) { + if (!receivers) + continue; + SMARTLIST_FOREACH(receivers, dispatch_rcv_t *, rcv, tor_free(rcv)); + smartlist_free(receivers); + } SMARTLIST_FOREACH_END(receivers); + smartlist_free(cfg->recv_by_msg); + + tor_free(cfg); +} diff --git a/src/lib/dispatch/dispatch_cfg.h b/src/lib/dispatch/dispatch_cfg.h new file mode 100644 index 0000000000..2c755e39bc --- /dev/null +++ b/src/lib/dispatch/dispatch_cfg.h @@ -0,0 +1,39 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_DISPATCH_CFG_H +#define TOR_DISPATCH_CFG_H + +#include "lib/dispatch/msgtypes.h" + +/** + * A "dispatch_cfg" is the configuration used to set up a dispatcher. + * It is created and accessed with a set of dcfg_* functions, and then + * used with dispatcher_new() to make the dispatcher. + */ +typedef struct dispatch_cfg_t dispatch_cfg_t; + +dispatch_cfg_t *dcfg_new(void); + +int dcfg_msg_set_type(dispatch_cfg_t *cfg, message_id_t msg, + msg_type_id_t type); + +int dcfg_msg_set_chan(dispatch_cfg_t *cfg, message_id_t msg, + channel_id_t chan); + +int dcfg_type_set_fns(dispatch_cfg_t *cfg, msg_type_id_t type, + const dispatch_typefns_t *fns); + +int dcfg_add_recv(dispatch_cfg_t *cfg, message_id_t msg, + subsys_id_t sys, recv_fn_t fn); + +/** Free a dispatch_cfg_t. */ +#define dcfg_free(cfg) \ + FREE_AND_NULL(dispatch_cfg_t, dcfg_free_, (cfg)) + +void dcfg_free_(dispatch_cfg_t *cfg); + +#endif diff --git a/src/lib/dispatch/dispatch_cfg_st.h b/src/lib/dispatch/dispatch_cfg_st.h new file mode 100644 index 0000000000..d004fe5934 --- /dev/null +++ b/src/lib/dispatch/dispatch_cfg_st.h @@ -0,0 +1,25 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_DISPATCH_CFG_ST_H +#define TOR_DISPATCH_CFG_ST_H + +struct smartlist_t; + +/* Information needed to create a dispatcher, but in a less efficient, more + * mutable format. */ +struct dispatch_cfg_t { + /** A list of msg_type_id_t (cast to void*), indexed by msg_t. */ + struct smartlist_t *type_by_msg; + /** A list of channel_id_t (cast to void*), indexed by msg_t. */ + struct smartlist_t *chan_by_msg; + /** A list of dispatch_rcv_t, indexed by msg_type_id_t. */ + struct smartlist_t *fns_by_type; + /** A list of dispatch_typefns_t, indexed by msg_t. */ + struct smartlist_t *recv_by_msg; +}; + +#endif diff --git a/src/lib/dispatch/dispatch_core.c b/src/lib/dispatch/dispatch_core.c new file mode 100644 index 0000000000..24dfc649a1 --- /dev/null +++ b/src/lib/dispatch/dispatch_core.c @@ -0,0 +1,234 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file dispatch_core.c + * \brief Core module for sending and receiving messages. + */ + +#define DISPATCH_PRIVATE +#include "orconfig.h" + +#include "lib/dispatch/dispatch.h" +#include "lib/dispatch/dispatch_st.h" + +#include "lib/malloc/malloc.h" +#include "lib/log/util_bug.h" + +#include <string.h> + +/** + * Use <b>d</b> to drop all storage held for <b>msg</b>. + * + * (We need the dispatcher so we know how to free the auxiliary data.) + **/ +void +dispatch_free_msg_(const dispatch_t *d, msg_t *msg) +{ + if (!msg) + return; + + d->typefns[msg->type].free_fn(msg->aux_data__); + tor_free(msg); +} + +/** + * Format the auxiliary data held by msg. + **/ +char * +dispatch_fmt_msg_data(const dispatch_t *d, const msg_t *msg) +{ + if (!msg) + return NULL; + + return d->typefns[msg->type].fmt_fn(msg->aux_data__); +} + +/** + * Release all storage held by <b>d</b>. + **/ +void +dispatch_free_(dispatch_t *d) +{ + if (d == NULL) + return; + + size_t n_queues = d->n_queues; + for (size_t i = 0; i < n_queues; ++i) { + msg_t *m, *mtmp; + TOR_SIMPLEQ_FOREACH_SAFE(m, &d->queues[i].queue, next, mtmp) { + dispatch_free_msg(d, m); + } + } + + size_t n_msgs = d->n_msgs; + + for (size_t i = 0; i < n_msgs; ++i) { + tor_free(d->table[i]); + } + tor_free(d->table); + tor_free(d->typefns); + tor_free(d->queues); + + // This is the only time we will treat d->cfg as non-const. + //dispatch_cfg_free_((dispatch_items_t *) d->cfg); + + tor_free(d); +} + +/** + * Tell the dispatcher to call <b>fn</b> with <b>userdata</b> whenever + * <b>chan</b> becomes nonempty. Return 0 on success, -1 on error. + **/ +int +dispatch_set_alert_fn(dispatch_t *d, channel_id_t chan, + dispatch_alertfn_t fn, void *userdata) +{ + if (BUG(chan >= d->n_queues)) + return -1; + + dqueue_t *q = &d->queues[chan]; + q->alert_fn = fn; + q->alert_fn_arg = userdata; + return 0; +} + +/** + * Send a message on the appropriate channel notifying that channel if + * necessary. + * + * This function takes ownership of the auxiliary data; it can't be static or + * stack-allocated, and the caller is not allowed to use it afterwards. + * + * This function does not check the various vields of the message object for + * consistency. + **/ +int +dispatch_send(dispatch_t *d, + subsys_id_t sender, + channel_id_t channel, + message_id_t msg, + msg_type_id_t type, + msg_aux_data_t auxdata) +{ + if (!d->table[msg]) { + /* Fast path: nobody wants this data. */ + + d->typefns[type].free_fn(auxdata); + return 0; + } + + msg_t *m = tor_malloc(sizeof(msg_t)); + + m->sender = sender; + m->channel = channel; + m->msg = msg; + m->type = type; + memcpy(&m->aux_data__, &auxdata, sizeof(msg_aux_data_t)); + + return dispatch_send_msg(d, m); +} + +int +dispatch_send_msg(dispatch_t *d, msg_t *m) +{ + if (BUG(!d)) + goto err; + if (BUG(!m)) + goto err; + if (BUG(m->channel >= d->n_queues)) + goto err; + if (BUG(m->msg >= d->n_msgs)) + goto err; + + dtbl_entry_t *ent = d->table[m->msg]; + if (ent) { + if (BUG(m->type != ent->type)) + goto err; + if (BUG(m->channel != ent->channel)) + goto err; + } + + return dispatch_send_msg_unchecked(d, m); + err: + /* Probably it isn't safe to free m, since type could be wrong. */ + return -1; +} + +/** + * Send a message on the appropriate queue, notifying that queue if necessary. + * + * This function takes ownership of the message object and its auxiliary data; + * it can't be static or stack-allocated, and the caller isn't allowed to use + * it afterwards. + * + * This function does not check the various fields of the message object for + * consistency, and can crash if they are out of range. Only functions that + * have already constructed the message in a safe way, or checked it for + * correctness themselves, should call this function. + **/ +int +dispatch_send_msg_unchecked(dispatch_t *d, msg_t *m) +{ + /* Find the right queue. */ + dqueue_t *q = &d->queues[m->channel]; + bool was_empty = TOR_SIMPLEQ_EMPTY(&q->queue); + + /* Append the message. */ + TOR_SIMPLEQ_INSERT_TAIL(&q->queue, m, next); + + /* If we just made the queue nonempty for the first time, call the alert + * function. */ + if (was_empty) { + q->alert_fn(d, m->channel, q->alert_fn_arg); + } + + return 0; +} + +/** + * Run all of the callbacks on <b>d</b> associated with <b>m</b>. + **/ +static void +dispatcher_run_msg_cbs(const dispatch_t *d, msg_t *m) +{ + tor_assert(m->msg <= d->n_msgs); + dtbl_entry_t *ent = d->table[m->msg]; + int n_fns = ent->n_fns; + + int i; + for (i=0; i < n_fns; ++i) { + if (ent->rcv[i].enabled) + ent->rcv[i].fn(m); + } +} + +/** + * Run up to <b>max_msgs</b> callbacks for messages on the channel <b>ch</b> + * on the given dispatcher. Return 0 on success or recoverable failure, + * -1 on unrecoverable error. + **/ +int +dispatch_flush(dispatch_t *d, channel_id_t ch, int max_msgs) +{ + if (BUG(ch >= d->n_queues)) + return 0; + + int n_flushed = 0; + dqueue_t *q = &d->queues[ch]; + + while (n_flushed < max_msgs) { + msg_t *m = TOR_SIMPLEQ_FIRST(&q->queue); + if (!m) + break; + TOR_SIMPLEQ_REMOVE_HEAD(&q->queue, next); + dispatcher_run_msg_cbs(d, m); + dispatch_free_msg(d, m); + ++n_flushed; + } + + return 0; +} diff --git a/src/lib/dispatch/dispatch_new.c b/src/lib/dispatch/dispatch_new.c new file mode 100644 index 0000000000..a2879016a7 --- /dev/null +++ b/src/lib/dispatch/dispatch_new.c @@ -0,0 +1,170 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file dispatch_new.c + * \brief Code to construct a dispatch_t from a dispatch_cfg_t. + **/ + +#define DISPATCH_PRIVATE +#include "orconfig.h" + +#include "lib/dispatch/dispatch.h" +#include "lib/dispatch/dispatch_st.h" +#include "lib/dispatch/dispatch_cfg.h" +#include "lib/dispatch/dispatch_cfg_st.h" + +#include "lib/intmath/cmp.h" +#include "lib/malloc/malloc.h" +#include "lib/log/util_bug.h" + +#include <string.h> + +/** Convert a void* in a smartlist to the corresponding integer. */ +#define VOID_TO_ID(p) ((intptr_t)(p)) + +/** Given a smartlist full of void* fields encoding intptr_t values, + * return the largest intptr_t, or dflt if the list is empty. */ +static intptr_t +max_in_sl(const smartlist_t *sl, intptr_t dflt) +{ + if (!smartlist_len(sl)) + return dflt; + void *as_ptr = smartlist_get(sl, 0); + intptr_t max = VOID_TO_ID(as_ptr); + SMARTLIST_FOREACH_BEGIN(sl, void *, p) { + intptr_t i = VOID_TO_ID(p); + if (i > max) + max = i; + } SMARTLIST_FOREACH_END(p); + return max; +} + +/** Helper: Format an unformattable message auxiliary data item: just return a +* copy of the string <>. */ +static char * +type_fmt_nop(msg_aux_data_t arg) +{ + (void)arg; + return tor_strdup("<>"); +} + +/** Helper: Free an unfreeable message auxiliary data item: do nothing. */ +static void +type_free_nop(msg_aux_data_t arg) +{ + (void)arg; +} + +/** Type functions to use when no type functions are provided. */ +static dispatch_typefns_t nop_typefns = { + .free_fn = type_free_nop, + .fmt_fn = type_fmt_nop +}; + +/** + * Alert function to use when none is configured: do nothing. + **/ +static void +alert_fn_nop(dispatch_t *d, channel_id_t ch, void *arg) +{ + (void)d; + (void)ch; + (void)arg; +} + +/** + * Given a list of recvfn_t, create and return a new dtbl_entry_t mapping + * to each of those functions. + **/ +static dtbl_entry_t * +dtbl_entry_from_lst(smartlist_t *receivers) +{ + if (!receivers) + return NULL; + + size_t n_recv = smartlist_len(receivers); + dtbl_entry_t *ent; + ent = tor_malloc_zero(offsetof(dtbl_entry_t, rcv) + + sizeof(dispatch_rcv_t) * n_recv); + + ent->n_fns = n_recv; + + SMARTLIST_FOREACH_BEGIN(receivers, const dispatch_rcv_t *, rcv) { + memcpy(&ent->rcv[rcv_sl_idx], rcv, sizeof(*rcv)); + if (rcv->enabled) { + ++ent->n_enabled; + } + } SMARTLIST_FOREACH_END(rcv); + + return ent; +} + +/** Create and return a new dispatcher from a given dispatch_cfg_t. */ +dispatch_t * +dispatch_new(const dispatch_cfg_t *cfg) +{ + dispatch_t *d = tor_malloc_zero(sizeof(dispatch_t)); + + /* Any message that has a type or a receiver counts towards our messages */ + const size_t n_msgs = MAX(smartlist_len(cfg->type_by_msg), + smartlist_len(cfg->recv_by_msg)) + 1; + + /* Any channel that any message has counts towards the number of channels. */ + const size_t n_chans = (size_t) MAX(1, max_in_sl(cfg->chan_by_msg,0)) + 1; + + /* Any type that a message has, or that has functions, counts towards + * the number of types. */ + const size_t n_types = (size_t) MAX(max_in_sl(cfg->type_by_msg,0), + smartlist_len(cfg->fns_by_type)) + 1; + + d->n_msgs = n_msgs; + d->n_queues = n_chans; + d->n_types = n_types; + + /* Initialize the array of type-functions. */ + d->typefns = tor_calloc(n_types, sizeof(dispatch_typefns_t)); + for (size_t i = 0; i < n_types; ++i) { + /* Default to no-op for everything... */ + memcpy(&d->typefns[i], &nop_typefns, sizeof(dispatch_typefns_t)); + } + SMARTLIST_FOREACH_BEGIN(cfg->fns_by_type, dispatch_typefns_t *, fns) { + /* Set the functions if they are provided. */ + if (fns) { + if (fns->free_fn) + d->typefns[fns_sl_idx].free_fn = fns->free_fn; + if (fns->fmt_fn) + d->typefns[fns_sl_idx].fmt_fn = fns->fmt_fn; + } + } SMARTLIST_FOREACH_END(fns); + + /* Initialize the message queues: one for each channel. */ + d->queues = tor_calloc(d->n_queues, sizeof(dqueue_t)); + for (size_t i = 0; i < d->n_queues; ++i) { + TOR_SIMPLEQ_INIT(&d->queues[i].queue); + d->queues[i].alert_fn = alert_fn_nop; + } + + /* Build the dispatch tables mapping message IDs to receivers. */ + d->table = tor_calloc(d->n_msgs, sizeof(dtbl_entry_t *)); + SMARTLIST_FOREACH_BEGIN(cfg->recv_by_msg, smartlist_t *, rcv) { + d->table[rcv_sl_idx] = dtbl_entry_from_lst(rcv); + } SMARTLIST_FOREACH_END(rcv); + + /* Fill in the empty entries in the dispatch tables: + * types and channels for each message. */ + SMARTLIST_FOREACH_BEGIN(cfg->type_by_msg, smartlist_t *, type) { + if (d->table[type_sl_idx]) + d->table[type_sl_idx]->type = VOID_TO_ID(type); + } SMARTLIST_FOREACH_END(type); + + SMARTLIST_FOREACH_BEGIN(cfg->chan_by_msg, smartlist_t *, chan) { + if (d->table[chan_sl_idx]) + d->table[chan_sl_idx]->channel = VOID_TO_ID(chan); + } SMARTLIST_FOREACH_END(chan); + + return d; +} diff --git a/src/lib/dispatch/dispatch_st.h b/src/lib/dispatch/dispatch_st.h new file mode 100644 index 0000000000..568107b700 --- /dev/null +++ b/src/lib/dispatch/dispatch_st.h @@ -0,0 +1,108 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file dispatch_st.h + * + * \brief private structures used for the dispatcher module + */ + +#ifndef TOR_DISPATCH_ST_H +#define TOR_DISPATCH_ST_H + +#ifdef DISPATCH_PRIVATE + +#include "lib/container/smartlist.h" + +/** + * Information about the recipient of a message. + **/ +typedef struct dispatch_rcv_t { + /** The subsystem receiving a message. */ + subsys_id_t sys; + /** True iff this recipient is enabled. */ + bool enabled; + /** The function that will handle the message. */ + recv_fn_t fn; +} dispatch_rcv_t; + +/** + * Information used by a dispatcher to handle and dispatch a single message + * ID. It maps that message ID to its type, channel, and list of receiver + * functions. + * + * This structure is used when the dispatcher is running. + **/ +typedef struct dtbl_entry_t { + /** The number of enabled non-stub subscribers for this message. + * + * Note that for now, this will be the same as <b>n_fns</b>, since there is + * no way to turn these subscribers on an off yet. */ + uint16_t n_enabled; + /** The channel that handles this message. */ + channel_id_t channel; + /** The associated C type for this message. */ + msg_type_id_t type; + /** + * The number of functions pointers for subscribers that receive this + * message, in rcv. */ + uint16_t n_fns; + /** + * The recipients for this message. + */ + dispatch_rcv_t rcv[FLEXIBLE_ARRAY_MEMBER]; +} dtbl_entry_t; + +/** + * A queue of messages for a given channel, used by a live dispatcher. + */ +typedef struct dqueue_t { + /** The queue of messages itself. */ + TOR_SIMPLEQ_HEAD( , msg_t) queue; + /** A function to be called when the queue becomes nonempty. */ + dispatch_alertfn_t alert_fn; + /** An argument for the alert_fn. */ + void *alert_fn_arg; +} dqueue_t ; + +/** + * A single dispatcher for cross-module messages. + */ +struct dispatch_t { + /** + * The length of <b>table</b>: the number of message IDs that this + * dispatcher can handle. + */ + size_t n_msgs; + /** + * The length of <b>queues</b>: the number of channels that this dispatcher + * has configured. + */ + size_t n_queues; + /** + * The length of <b>typefns</b>: the number of C type IDs that this + * dispatcher has configured. + */ + size_t n_types; + /** + * An array of message queues, indexed by channel ID. + */ + dqueue_t *queues; + /** + * An array of entries about how to handle particular message types, indexed + * by message ID. + */ + dtbl_entry_t **table; + /** + * An array of function tables for manipulating types, index by message + * type ID. + **/ + dispatch_typefns_t *typefns; +}; + +#endif + +#endif diff --git a/src/lib/dispatch/include.am b/src/lib/dispatch/include.am new file mode 100644 index 0000000000..c4aa170dbc --- /dev/null +++ b/src/lib/dispatch/include.am @@ -0,0 +1,23 @@ + +noinst_LIBRARIES += src/lib/libtor-dispatch.a + +if UNITTESTS_ENABLED +noinst_LIBRARIES += src/lib/libtor-dispatch-testing.a +endif + +src_lib_libtor_dispatch_a_SOURCES = \ + src/lib/dispatch/dispatch_cfg.c \ + src/lib/dispatch/dispatch_core.c \ + src/lib/dispatch/dispatch_new.c + +src_lib_libtor_dispatch_testing_a_SOURCES = \ + $(src_lib_libtor_dispatch_a_SOURCES) +src_lib_libtor_dispatch_testing_a_CPPFLAGS = $(AM_CPPFLAGS) $(TEST_CPPFLAGS) +src_lib_libtor_dispatch_testing_a_CFLAGS = $(AM_CFLAGS) $(TEST_CFLAGS) + +noinst_HEADERS += \ + src/lib/dispatch/dispatch.h \ + src/lib/dispatch/dispatch_cfg.h \ + src/lib/dispatch/dispatch_cfg_st.h \ + src/lib/dispatch/dispatch_st.h \ + src/lib/dispatch/msgtypes.h diff --git a/src/lib/dispatch/msgtypes.h b/src/lib/dispatch/msgtypes.h new file mode 100644 index 0000000000..4e79e592a6 --- /dev/null +++ b/src/lib/dispatch/msgtypes.h @@ -0,0 +1,80 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file msgtypes.h + * \brief Types used for messages in the dispatcher code. + **/ + +#ifndef TOR_DISPATCH_MSGTYPES_H +#define TOR_DISPATCH_MSGTYPES_H + +#include <stdint.h> + +#include "ext/tor_queue.h" + +/** + * These types are aliases for subsystems, channels, and message IDs. + **/ +typedef uint16_t subsys_id_t; +typedef uint16_t channel_id_t; +typedef uint16_t message_id_t; + +/** + * This identifies a C type that can be sent along with a message. + **/ +typedef uint16_t msg_type_id_t; + +/** + * An ID value returned for *_type_t when none exists. + */ +#define ERROR_ID 65535 + +/** + * Auxiliary (untyped) data sent along with a message. + * + * We define this as a union of a pointer and a u64, so that the integer + * types will have the same range across platforms. + **/ +typedef union { + void *ptr; + uint64_t u64; +} msg_aux_data_t; + +/** + * Structure of a received message. + **/ +typedef struct msg_t { + TOR_SIMPLEQ_ENTRY(msg_t) next; + subsys_id_t sender; + channel_id_t channel; + message_id_t msg; + /** We could omit this field, since it is implicit in the message type, but + * IMO let's leave it in for safety. */ + msg_type_id_t type; + /** Untyped auxiliary data. You shouldn't have to mess with this + * directly. */ + msg_aux_data_t aux_data__; +} msg_t; + +/** + * A function that a subscriber uses to receive a message. + **/ +typedef void (*recv_fn_t)(const msg_t *m); + +/** + * Table of functions to use for a given C type. Any omitted (NULL) functions + * will be treated as no-ops. + **/ +typedef struct dispatch_typefns_t { + /** Release storage held for the auxiliary data of this type. */ + void (*free_fn)(msg_aux_data_t); + /** Format and return a newly allocated string describing the contents + * of this data element. */ + char *(*fmt_fn)(msg_aux_data_t); +} dispatch_typefns_t; + +#endif diff --git a/src/test/include.am b/src/test/include.am index c3827d3eb9..d4e8eb4e8c 100644 --- a/src/test/include.am +++ b/src/test/include.am @@ -124,6 +124,7 @@ src_test_test_SOURCES += \ src/test/test_dir.c \ src/test/test_dir_common.c \ src/test/test_dir_handle_get.c \ + src/test/test_dispatch.c \ src/test/test_dos.c \ src/test/test_entryconn.c \ src/test/test_entrynodes.c \ diff --git a/src/test/test.c b/src/test/test.c index 1230b632a5..4c6d9775b4 100644 --- a/src/test/test.c +++ b/src/test/test.c @@ -872,6 +872,7 @@ struct testgroup_t testgroups[] = { { "dir/voting/flags/", voting_flags_tests }, { "dir/voting/schedule/", voting_schedule_tests }, { "dir_handle_get/", dir_handle_get_tests }, + { "dispatch/", dispatch_tests, }, { "dns/", dns_tests }, { "dos/", dos_tests }, { "entryconn/", entryconn_tests }, diff --git a/src/test/test.h b/src/test/test.h index 7a3a4d8fdc..cd0ce4f6df 100644 --- a/src/test/test.h +++ b/src/test/test.h @@ -209,6 +209,7 @@ extern struct testcase_t crypto_openssl_tests[]; extern struct testcase_t crypto_tests[]; extern struct testcase_t dir_handle_get_tests[]; extern struct testcase_t dir_tests[]; +extern struct testcase_t dispatch_tests[]; extern struct testcase_t dns_tests[]; extern struct testcase_t dos_tests[]; extern struct testcase_t entryconn_tests[]; diff --git a/src/test/test_dispatch.c b/src/test/test_dispatch.c new file mode 100644 index 0000000000..ec704c042a --- /dev/null +++ b/src/test/test_dispatch.c @@ -0,0 +1,181 @@ +/* Copyright (c) 2018, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#define DISPATCH_PRIVATE + +#include "test/test.h" + +#include "lib/dispatch/dispatch.h" +#include "lib/dispatch/dispatch_cfg.h" +#include "lib/dispatch/dispatch_st.h" +#include "lib/dispatch/msgtypes.h" + +#include "lib/log/escape.h" +#include "lib/malloc/malloc.h" +#include "lib/string/printf.h" + +#include <stdio.h> +#include <string.h> + +/* Construct an empty dispatch_t. */ +static void +test_dispatch_empty(void *arg) +{ + (void)arg; + + dispatch_t *d=NULL; + dispatch_cfg_t *cfg=NULL; + + cfg = dcfg_new(); + d = dispatch_new(cfg); + tt_assert(d); + + done: + dispatch_free(d); + dcfg_free(cfg); +} + +static int total_recv1_simple = 0; +static int total_recv2_simple = 0; + +static void +simple_recv1(const msg_t *m) +{ + total_recv1_simple += m->aux_data__.u64; +} + +static void +simple_recv2(const msg_t *m) +{ + total_recv2_simple += m->aux_data__.u64*10; +} + +/* Construct a dispatch_t with two messages, make sure that they both get + * delivered. */ +static void +test_dispatch_simple(void *arg) +{ + (void)arg; + + dispatch_t *d=NULL; + dispatch_cfg_t *cfg=NULL; + int r; + + cfg = dcfg_new(); + r = dcfg_msg_set_type(cfg,0,0); + r += dcfg_msg_set_chan(cfg,0,0); + r += dcfg_add_recv(cfg,0,1,simple_recv1); + r += dcfg_msg_set_type(cfg,1,0); + r += dcfg_msg_set_chan(cfg,1,0); + r += dcfg_add_recv(cfg,1,1,simple_recv2); + r += dcfg_add_recv(cfg,1,1,simple_recv2); /* second copy */ + tt_int_op(r, OP_EQ, 0); + + d = dispatch_new(cfg); + tt_assert(d); + + msg_aux_data_t data = {.u64 = 7}; + r = dispatch_send(d, 99, 0, 0, 0, data); + tt_int_op(r, OP_EQ, 0); + tt_int_op(total_recv1_simple, OP_EQ, 0); + + r = dispatch_flush(d, 0, INT_MAX); + tt_int_op(r, OP_EQ, 0); + tt_int_op(total_recv1_simple, OP_EQ, 7); + tt_int_op(total_recv2_simple, OP_EQ, 0); + + total_recv1_simple = 0; + r = dispatch_send(d, 99, 0, 1, 0, data); + tt_int_op(r, OP_EQ, 0); + r = dispatch_flush(d, 0, INT_MAX); + tt_int_op(total_recv1_simple, OP_EQ, 0); + tt_int_op(total_recv2_simple, OP_EQ, 140); + + done: + dispatch_free(d); + dcfg_free(cfg); +} + +struct coord { int x; int y; }; +static void +free_coord(msg_aux_data_t d) +{ + tor_free(d.ptr); +} +static char * +fmt_coord(msg_aux_data_t d) +{ + char *v; + struct coord *c = d.ptr; + tor_asprintf(&v, "[%d, %d]", c->x, c->y); + return v; +} +static dispatch_typefns_t coord_fns = { + .fmt_fn = fmt_coord, + .free_fn = free_coord, +}; +static void +alert_run_immediate(dispatch_t *d, channel_id_t ch, void *arg) +{ + (void)arg; + dispatch_flush(d, ch, INT_MAX); +} + +static dispatch_t *dispatcher_in_use=NULL; +static char *received_data=NULL; + +static void +recv_typed_data(const msg_t *m) +{ + tor_free(received_data); + received_data = dispatch_fmt_msg_data(dispatcher_in_use, m); +} + +static void +test_dispatch_with_types(void *arg) +{ + (void)arg; + + dispatch_t *d=NULL; + dispatch_cfg_t *cfg=NULL; + int r; + + cfg = dcfg_new(); + r = dcfg_msg_set_type(cfg,5,3); + r += dcfg_msg_set_chan(cfg,5,2); + r += dcfg_add_recv(cfg,5,0,recv_typed_data); + r += dcfg_type_set_fns(cfg,3,&coord_fns); + tt_int_op(r, OP_EQ, 0); + + d = dispatch_new(cfg); + tt_assert(d); + dispatcher_in_use = d; + + /* Make this message get run immediately. */ + r = dispatch_set_alert_fn(d, 2, alert_run_immediate, NULL); + tt_int_op(r, OP_EQ, 0); + + struct coord *xy = tor_malloc(sizeof(*xy)); + xy->x = 13; + xy->y = 37; + msg_aux_data_t data = {.ptr = xy}; + r = dispatch_send(d, 99/*sender*/, 2/*channel*/, 5/*msg*/, 3/*type*/, data); + tt_int_op(r, OP_EQ, 0); + tt_str_op(received_data, OP_EQ, "[13, 37]"); + + done: + dispatch_free(d); + dcfg_free(cfg); + tor_free(received_data); + dispatcher_in_use = NULL; +} + +#define T(name) \ + { #name, test_dispatch_ ## name, TT_FORK, NULL, NULL } + +struct testcase_t dispatch_tests[] = { + T(empty), + T(simple), + T(with_types), + END_OF_TESTCASES +}; |