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-rw-r--r--src/common/address.c2
-rw-r--r--src/common/address.h2
-rw-r--r--src/common/compat.h2
-rw-r--r--src/common/crypto.c18
-rw-r--r--src/common/crypto_s2k.c6
-rw-r--r--src/common/handles.h153
-rw-r--r--src/common/include.am10
-rw-r--r--src/common/memarea.c6
-rw-r--r--src/common/timers.c297
-rw-r--r--src/common/timers.h22
-rw-r--r--src/common/util.c17
-rw-r--r--src/common/util.h41
-rw-r--r--src/common/util_bug.c53
-rw-r--r--src/common/util_bug.h150
14 files changed, 703 insertions, 76 deletions
diff --git a/src/common/address.c b/src/common/address.c
index 793a40effc..a6e0f3f491 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -1172,7 +1172,7 @@ tor_addr_hash(const tor_addr_t *addr)
/** Return a newly allocated string with a representation of <b>addr</b>. */
char *
-tor_dup_addr(const tor_addr_t *addr)
+tor_addr_to_str_dup(const tor_addr_t *addr)
{
char buf[TOR_ADDR_BUF_LEN];
if (tor_addr_to_str(buf, addr, sizeof(buf), 0)) {
diff --git a/src/common/address.h b/src/common/address.h
index 53712bde02..3de67e1c74 100644
--- a/src/common/address.h
+++ b/src/common/address.h
@@ -179,7 +179,7 @@ tor_addr_eq_ipv4h(const tor_addr_t *a, uint32_t u)
#define TOR_ADDR_BUF_LEN 48
int tor_addr_lookup(const char *name, uint16_t family, tor_addr_t *addr_out);
-char *tor_dup_addr(const tor_addr_t *addr) ATTR_MALLOC;
+char *tor_addr_to_str_dup(const tor_addr_t *addr) ATTR_MALLOC;
/** Wrapper function of fmt_addr_impl(). It does not decorate IPv6
* addresses. */
diff --git a/src/common/compat.h b/src/common/compat.h
index 8cf84580c6..b6ee4106db 100644
--- a/src/common/compat.h
+++ b/src/common/compat.h
@@ -430,7 +430,7 @@ typedef int socklen_t;
#ifdef _WIN32
/* XXX Actually, this should arguably be SOCKET; we use intptr_t here so that
- * any inadvertant checks for the socket being <= 0 or > 0 will probably
+ * any inadvertent checks for the socket being <= 0 or > 0 will probably
* still work. */
#define tor_socket_t intptr_t
#define TOR_SOCKET_T_FORMAT INTPTR_T_FORMAT
diff --git a/src/common/crypto.c b/src/common/crypto.c
index d2a42698cb..65a575ebea 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -134,7 +134,7 @@ crypto_get_rsa_padding_overhead(int padding)
switch (padding)
{
case RSA_PKCS1_OAEP_PADDING: return PKCS1_OAEP_PADDING_OVERHEAD;
- default: tor_assert(0); return -1;
+ default: tor_assert(0); return -1; // LCOV_EXCL_LINE
}
}
@@ -146,7 +146,7 @@ crypto_get_rsa_padding(int padding)
switch (padding)
{
case PK_PKCS1_OAEP_PADDING: return RSA_PKCS1_OAEP_PADDING;
- default: tor_assert(0); return -1;
+ default: tor_assert(0); return -1; // LCOV_EXCL_LINE
}
}
@@ -1739,8 +1739,8 @@ crypto_digest_algorithm_get_length(digest_algorithm_t alg)
case DIGEST_SHA3_512:
return DIGEST512_LEN;
default:
- tor_assert(0);
- return 0; /* Unreachable */
+ tor_assert(0); // LCOV_EXCL_LINE
+ return 0; /* Unreachable */ // LCOV_EXCL_LINE
}
}
@@ -1783,8 +1783,8 @@ crypto_digest_alloc_bytes(digest_algorithm_t alg)
case DIGEST_SHA3_512:
return END_OF_FIELD(d.sha3);
default:
- tor_assert(0);
- return 0;
+ tor_assert(0); // LCOV_EXCL_LINE
+ return 0; // LCOV_EXCL_LINE
}
#undef END_OF_FIELD
#undef STRUCT_FIELD_SIZE
@@ -1914,6 +1914,7 @@ crypto_digest_get_digest(crypto_digest_t *digest,
case DIGEST_SHA512:
SHA512_Final(r, &tmpenv.d.sha512);
break;
+//LCOV_EXCL_START
case DIGEST_SHA3_256: /* FALLSTHROUGH */
case DIGEST_SHA3_512:
log_warn(LD_BUG, "Handling unexpected algorithm %d", digest->algorithm);
@@ -1921,6 +1922,7 @@ crypto_digest_get_digest(crypto_digest_t *digest,
default:
tor_assert(0); /* Unreachable. */
break;
+//LCOV_EXCL_STOP
}
memcpy(out, r, out_len);
memwipe(r, 0, sizeof(r));
@@ -2382,8 +2384,6 @@ tor_check_dh_key(int severity, BIGNUM *bn)
return -1;
}
-#undef MIN
-#define MIN(a,b) ((a)<(b)?(a):(b))
/** Given a DH key exchange object, and our peer's value of g^y (as a
* <b>pubkey_len</b>-byte value in <b>pubkey</b>) generate
* <b>secret_bytes_out</b> bytes of shared key material and write them
@@ -2760,10 +2760,12 @@ crypto_strongest_rand(uint8_t *out, size_t out_len)
while (out_len) {
crypto_rand((char*) inp, DLEN);
if (crypto_strongest_rand_raw(inp+DLEN, DLEN) < 0) {
+ // LCOV_EXCL_START
log_err(LD_CRYPTO, "Failed to load strong entropy when generating an "
"important key. Exiting.");
/* Die with an assertion so we get a stack trace. */
tor_assert(0);
+ // LCOV_EXCL_STOP
}
if (out_len >= DLEN) {
SHA512(inp, sizeof(inp), out);
diff --git a/src/common/crypto_s2k.c b/src/common/crypto_s2k.c
index a9140c7553..149c39344c 100644
--- a/src/common/crypto_s2k.c
+++ b/src/common/crypto_s2k.c
@@ -57,7 +57,8 @@
#define SCRYPT_KEY_LEN 32
/** Given an algorithm ID (one of S2K_TYPE_*), return the length of the
- * specifier part of it, without the prefix type byte. */
+ * specifier part of it, without the prefix type byte. Return -1 if it is not
+ * a valid algorithm ID. */
static int
secret_to_key_spec_len(uint8_t type)
{
@@ -86,7 +87,8 @@ secret_to_key_key_len(uint8_t type)
case S2K_TYPE_SCRYPT:
return DIGEST256_LEN;
default:
- return -1;
+ tor_fragile_assert(); // LCOV_EXCL_LINE
+ return -1; // LCOV_EXCL_LINE
}
}
diff --git a/src/common/handles.h b/src/common/handles.h
new file mode 100644
index 0000000000..1ee2322579
--- /dev/null
+++ b/src/common/handles.h
@@ -0,0 +1,153 @@
+/* Copyright (c) 2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file handles.h
+ * \brief Macros for C weak-handle implementation.
+ *
+ * A 'handle' is a pointer to an object that is allowed to go away while
+ * the handle stays alive. When you dereference the handle, you might get
+ * the object, or you might get "NULL".
+ *
+ * Use this pattern when an object has a single obvious lifespan, so you don't
+ * want to use reference counting, but when other objects might need to refer
+ * to the first object without caring about its lifetime.
+ *
+ * To enable a type to have handles, add a HANDLE_ENTRY() field in its
+ * definition, as in:
+ *
+ * struct walrus {
+ * HANDLE_ENTRY(wlr, walrus);
+ * // ...
+ * };
+ *
+ * And invoke HANDLE_DECL(wlr, walrus, [static]) to declare the handle
+ * manipulation functions (typically in a header):
+ *
+ * // opaque handle to walrus.
+ * typedef struct wlr_handle_t wlr_handle_t;
+ *
+ * // make a new handle
+ * struct wlr_handle_t *wlr_handle_new(struct walrus *);
+ *
+ * // release a handle
+ * void wlr_handle_free(wlr_handle_t *);
+ *
+ * // return the pointed-to walrus, or NULL.
+ * struct walrus *wlr_handle_get(wlr_handle_t *).
+ *
+ * // call this function when you're about to free the walrus;
+ * // it invalidates all handles. (IF YOU DON'T, YOU WILL HAVE
+ * // DANGLING REFERENCES)
+ * void wlr_handles_clear(struct walrus *);
+ *
+ * Finally, use HANDLE_IMPL() to define the above functions in some
+ * appropriate C file: HANDLE_IMPL(wlr, walrus, [static])
+ *
+ **/
+
+#ifndef TOR_HANDLE_H
+#define TOR_HANDLE_H
+
+#include "orconfig.h"
+#include "tor_queue.h"
+#include "util.h"
+
+#define HANDLE_ENTRY(name, structname) \
+ struct name ## _handle_head_t *handle_head
+
+#define HANDLE_DECL(name, structname, linkage) \
+ typedef struct name ## _handle_t name ## _handle_t; \
+ linkage name ## _handle_t *name ## _handle_new(struct structname *object); \
+ linkage void name ## _handle_free(name ## _handle_t *); \
+ linkage struct structname *name ## _handle_get(name ## _handle_t *); \
+ linkage void name ## _handles_clear(struct structname *object);
+
+/*
+ * Implementation notes: there are lots of possible implementations here. We
+ * could keep a linked list of handles, each with a backpointer to the object,
+ * and set all of their backpointers to NULL when the object is freed. Or we
+ * could have the clear function invalidate the object, but not actually let
+ * the object get freed until the all the handles went away. We could even
+ * have a hash-table mapping unique identifiers to objects, and have each
+ * handle be a copy of the unique identifier. (We'll want to build that last
+ * one eventually if we want cross-process handles.)
+ *
+ * But instead we're opting for a single independent 'head' that knows how
+ * many handles there are, and where the object is (or isn't). This makes
+ * all of our functions O(1), and most as fast as a single pointer access.
+ *
+ * The handles themselves are opaque structures holding a pointer to the head.
+ * We could instead have each foo_handle_t* be identical to foo_handle_head_t
+ * *, and save some allocations ... but doing so would make handle leaks
+ * harder to debug. As it stands, every handle leak is a memory leak, and
+ * existing memory debugging tools should help with those. We can revisit
+ * this decision if handles are too slow.
+ */
+
+#define HANDLE_IMPL(name, structname, linkage) \
+ /* The 'head' object for a handle-accessible type. This object */ \
+ /* persists for as long as the object, or any handles, exist. */ \
+ typedef struct name ## _handle_head_t { \
+ struct structname *object; /* pointed-to object, or NULL */ \
+ unsigned int references; /* number of existing handles */ \
+ } name ## _handle_head_t; \
+ \
+ struct name ## _handle_t { \
+ struct name ## _handle_head_t *head; /* reference to the 'head'. */ \
+ }; \
+ \
+ linkage struct name ## _handle_t * \
+ name ## _handle_new(struct structname *object) \
+ { \
+ tor_assert(object); \
+ name ## _handle_head_t *head = object->handle_head; \
+ if (PREDICT_UNLIKELY(head == NULL)) { \
+ head = object->handle_head = tor_malloc_zero(sizeof(*head)); \
+ head->object = object; \
+ } \
+ name ## _handle_t *new_ref = tor_malloc_zero(sizeof(*new_ref)); \
+ new_ref->head = head; \
+ ++head->references; \
+ return new_ref; \
+ } \
+ \
+ linkage void \
+ name ## _handle_free(struct name ## _handle_t *ref) \
+ { \
+ if (! ref) return; \
+ name ## _handle_head_t *head = ref->head; \
+ tor_assert(head); \
+ --head->references; \
+ tor_free(ref); \
+ if (head->object == NULL && head->references == 0) { \
+ tor_free(head); \
+ return; \
+ } \
+ } \
+ \
+ linkage struct structname * \
+ name ## _handle_get(struct name ## _handle_t *ref) \
+ { \
+ tor_assert(ref); \
+ name ## _handle_head_t *head = ref->head; \
+ tor_assert(head); \
+ return head->object; \
+ } \
+ \
+ linkage void \
+ name ## _handles_clear(struct structname *object) \
+ { \
+ tor_assert(object); \
+ name ## _handle_head_t *head = object->handle_head; \
+ if (! head) \
+ return; \
+ object->handle_head = NULL; \
+ head->object = NULL; \
+ if (head->references == 0) { \
+ tor_free(head); \
+ } \
+ }
+
+#endif /* TOR_HANDLE_H */
+
diff --git a/src/common/include.am b/src/common/include.am
index 5afb30da6a..bae90ad977 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -68,12 +68,12 @@ LIBOR_A_SOURCES = \
src/common/log.c \
src/common/memarea.c \
src/common/util.c \
+ src/common/util_bug.c \
src/common/util_format.c \
src/common/util_process.c \
src/common/sandbox.c \
src/common/workqueue.c \
src/ext/csiphash.c \
- src/ext/trunnel/trunnel.c \
$(libor_extra_source) \
$(threads_impl_source) \
$(readpassphrase_source)
@@ -89,13 +89,14 @@ LIBOR_CRYPTO_A_SOURCES = \
src/common/crypto_format.c \
src/common/torgzip.c \
src/common/tortls.c \
- src/trunnel/pwbox.c \
src/common/crypto_curve25519.c \
src/common/crypto_ed25519.c
LIBOR_EVENT_A_SOURCES = \
src/common/compat_libevent.c \
- src/common/procmon.c
+ src/common/procmon.c \
+ src/common/timers.c \
+ src/ext/timeouts/timeout.c
src_common_libor_a_SOURCES = $(LIBOR_A_SOURCES)
src_common_libor_crypto_a_SOURCES = $(LIBOR_CRYPTO_A_SOURCES)
@@ -129,16 +130,19 @@ COMMONHEADERS = \
src/common/crypto_pwbox.h \
src/common/crypto_s2k.h \
src/common/di_ops.h \
+ src/common/handles.h \
src/common/memarea.h \
src/common/linux_syscalls.inc \
src/common/procmon.h \
src/common/sandbox.h \
src/common/testsupport.h \
+ src/common/timers.h \
src/common/torgzip.h \
src/common/torint.h \
src/common/torlog.h \
src/common/tortls.h \
src/common/util.h \
+ src/common/util_bug.h \
src/common/util_format.h \
src/common/util_process.h \
src/common/workqueue.h
diff --git a/src/common/memarea.c b/src/common/memarea.c
index 0a3fd009b0..61117288c3 100644
--- a/src/common/memarea.c
+++ b/src/common/memarea.c
@@ -132,7 +132,7 @@ alloc_chunk(size_t sz)
/** Release <b>chunk</b> from a memarea. */
static void
-chunk_free_unchecked(memarea_chunk_t *chunk)
+memarea_chunk_free_unchecked(memarea_chunk_t *chunk)
{
CHECK_SENTINEL(chunk);
tor_free(chunk);
@@ -155,7 +155,7 @@ memarea_drop_all(memarea_t *area)
memarea_chunk_t *chunk, *next;
for (chunk = area->first; chunk; chunk = next) {
next = chunk->next_chunk;
- chunk_free_unchecked(chunk);
+ memarea_chunk_free_unchecked(chunk);
}
area->first = NULL; /*fail fast on */
tor_free(area);
@@ -171,7 +171,7 @@ memarea_clear(memarea_t *area)
if (area->first->next_chunk) {
for (chunk = area->first->next_chunk; chunk; chunk = next) {
next = chunk->next_chunk;
- chunk_free_unchecked(chunk);
+ memarea_chunk_free_unchecked(chunk);
}
area->first->next_chunk = NULL;
}
diff --git a/src/common/timers.c b/src/common/timers.c
new file mode 100644
index 0000000000..5d8d1feafd
--- /dev/null
+++ b/src/common/timers.c
@@ -0,0 +1,297 @@
+/* Copyright (c) 2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file timers.c
+ * \brief Wrapper around William Ahern's fast hierarchical timer wheel
+ * implementation, to tie it in with a libevent backend.
+ *
+ * Only use these functions from the main thread.
+ *
+ * The main advantage of tor_timer_t over using libevent's timers is that
+ * they're way more efficient if we need to have thousands or millions of
+ * them. For more information, see
+ * http://www.25thandclement.com/~william/projects/timeout.c.html
+ *
+ * Periodic timers are available in the backend, but I've turned them off.
+ * We can turn them back on if needed.
+ */
+
+/* Notes:
+ *
+ * The use of tor_gettimeofday_cached_monotonic() is kind of ugly. It would
+ * be neat to fix it.
+ *
+ * Having a way to free all timers on shutdown would free people from the
+ * need to track them. Not sure if that's clever though.
+ *
+ * In an ideal world, Libevent would just switch to use this backend, and we
+ * could throw this file away. But even if Libevent does switch, we'll be
+ * stuck with legacy libevents for some time.
+ */
+
+#include "orconfig.h"
+
+#include "compat.h"
+#include "compat_libevent.h"
+#include "timers.h"
+#include "torlog.h"
+#include "util.h"
+
+#ifdef HAVE_EVENT2_EVENT_H
+#include <event2/event.h>
+#else
+#include <event.h>
+#endif
+
+struct timeout_cb {
+ timer_cb_fn_t cb;
+ void *arg;
+};
+
+/*
+ * These definitions are for timeouts.c and timeouts.h.
+ */
+#ifdef __GNUC__
+/* We're not exposing any of the functions outside this file. */
+#define TIMEOUT_PUBLIC __attribute__((__unused__)) static
+#else
+/* We're not exposing any of the functions outside this file. */
+#define TIMEOUT_PUBLIC static
+#endif
+/* We're not using periodic events. */
+#define TIMEOUT_DISABLE_INTERVALS
+/* We always know the global_timeouts object, so we don't need each timeout
+ * to keep a pointer to it. */
+#define TIMEOUT_DISABLE_RELATIVE_ACCESS
+/* We're providing our own struct timeout_cb. */
+#define TIMEOUT_CB_OVERRIDE
+/* We're going to support timers that are pretty far out in advance. Making
+ * this big can be inefficient, but having a significant number of timers
+ * above TIMEOUT_MAX can also be super-inefficent. Choosing 5 here sets
+ * timeout_max to 2^30 ticks, or 29 hours with our value for USEC_PER_TICK */
+#define WHEEL_NUM 5
+#include "src/ext/timeouts/timeout.c"
+
+static struct timeouts *global_timeouts = NULL;
+static struct event *global_timer_event = NULL;
+
+/** We need to choose this value carefully. Because we're using timer wheels,
+ * it actually costs us to have extra resolution we don't use. So for now,
+ * I'm going to define our resolution as .1 msec, and hope that's good enough.
+ *
+ * Note that two of the most popular libevent backends (epoll without timerfd,
+ * and windows select), simply can't support sub-millisecond resolution,
+ * do this is optimistic for a lot of users.
+ */
+#define USEC_PER_TICK 100
+
+/** One million microseconds in a second */
+#define USEC_PER_SEC 1000000
+
+/** Check at least once every N seconds. */
+#define MIN_CHECK_SECONDS 3600
+
+/** Check at least once every N ticks. */
+#define MIN_CHECK_TICKS \
+ (((timeout_t)MIN_CHECK_SECONDS) * (1000000 / USEC_PER_TICK))
+
+/**
+ * Convert the timeval in <b>tv</b> to a timeout_t, and return it.
+ *
+ * The output resolution is set by USEC_PER_TICK, and the time corresponding
+ * to 0 is the same as the time corresponding to 0 from
+ * tor_gettimeofday_cached_monotonic().
+ */
+static timeout_t
+tv_to_timeout(const struct timeval *tv)
+{
+ uint64_t usec = tv->tv_usec;
+ usec += ((uint64_t)USEC_PER_SEC) * tv->tv_sec;
+ return usec / USEC_PER_TICK;
+}
+
+/**
+ * Convert the timeout in <b>t</b> to a timeval in <b>tv_out</b>
+ */
+static void
+timeout_to_tv(timeout_t t, struct timeval *tv_out)
+{
+ t *= USEC_PER_TICK;
+ tv_out->tv_usec = (int)(t % USEC_PER_SEC);
+ tv_out->tv_sec = (time_t)(t / USEC_PER_SEC);
+}
+
+/**
+ * Update the timer <b>tv</b> to the current time in <b>tv</b>.
+ */
+static void
+timer_advance_to_cur_time(const struct timeval *tv)
+{
+ timeout_t cur_tick = tv_to_timeout(tv);
+ if (BUG(cur_tick < timeouts_get_curtime(global_timeouts))) {
+ cur_tick = timeouts_get_curtime(global_timeouts); // LCOV_EXCL_LINE
+ }
+ timeouts_update(global_timeouts, cur_tick);
+}
+
+/**
+ * Adjust the time at which the libevent timer should fire based on
+ * the next-expiring time in <b>global_timeouts</b>
+ */
+static void
+libevent_timer_reschedule(void)
+{
+ struct timeval now;
+ tor_gettimeofday_cached_monotonic(&now);
+ timer_advance_to_cur_time(&now);
+
+ timeout_t delay = timeouts_timeout(global_timeouts);
+ struct timeval d;
+ if (delay > MIN_CHECK_TICKS)
+ delay = MIN_CHECK_TICKS;
+ timeout_to_tv(delay, &d);
+ event_add(global_timer_event, &d);
+}
+
+/**
+ * Invoked when the libevent timer has expired: see which tor_timer_t events
+ * have fired, activate their callbacks, and reschedule the libevent timer.
+ */
+static void
+libevent_timer_callback(evutil_socket_t fd, short what, void *arg)
+{
+ (void)fd;
+ (void)what;
+ (void)arg;
+
+ struct timeval now;
+ tor_gettimeofday_cache_clear();
+ tor_gettimeofday_cached_monotonic(&now);
+ timer_advance_to_cur_time(&now);
+
+ tor_timer_t *t;
+ while ((t = timeouts_get(global_timeouts))) {
+ t->callback.cb(t, t->callback.arg, &now);
+ }
+
+ tor_gettimeofday_cache_clear();
+ libevent_timer_reschedule();
+}
+
+/**
+ * Initialize the timers subsystem. Requires that libevent has already been
+ * initialized.
+ */
+void
+timers_initialize(void)
+{
+ if (BUG(global_timeouts))
+ return; // LCOV_EXCL_LINE
+
+ timeout_error_t err;
+ global_timeouts = timeouts_open(0, &err);
+ if (!global_timeouts) {
+ // LCOV_EXCL_START -- this can only fail on malloc failure.
+ log_err(LD_BUG, "Unable to open timer backend: %s", strerror(err));
+ tor_assert(0);
+ // LCOV_EXCL_STOP
+ }
+
+ struct event *timer_event;
+ timer_event = tor_event_new(tor_libevent_get_base(),
+ -1, 0, libevent_timer_callback, NULL);
+ tor_assert(timer_event);
+ global_timer_event = timer_event;
+
+ libevent_timer_reschedule();
+}
+
+/**
+ * Release all storage held in the timers subsystem. Does not fire timers.
+ */
+void
+timers_shutdown(void)
+{
+ if (global_timer_event) {
+ tor_event_free(global_timer_event);
+ global_timer_event = NULL;
+ }
+ if (global_timeouts) {
+ timeouts_close(global_timeouts);
+ global_timeouts = NULL;
+ }
+}
+
+/**
+ * Allocate and return a new timer, with given callback and argument.
+ */
+tor_timer_t *
+timer_new(timer_cb_fn_t cb, void *arg)
+{
+ tor_timer_t *t = tor_malloc(sizeof(tor_timer_t));
+ timeout_init(t, 0);
+ timer_set_cb(t, cb, arg);
+ return t;
+}
+
+/**
+ * Release all storage held by <b>t</b>, and unschedule it if was already
+ * scheduled.
+ */
+void
+timer_free(tor_timer_t *t)
+{
+ if (! t)
+ return;
+
+ timeouts_del(global_timeouts, t);
+ tor_free(t);
+}
+
+/**
+ * Change the callback and argument associated with a timer <b>t</b>.
+ */
+void
+timer_set_cb(tor_timer_t *t, timer_cb_fn_t cb, void *arg)
+{
+ t->callback.cb = cb;
+ t->callback.arg = arg;
+}
+
+/**
+ * Schedule the timer t to fire at the current time plus a delay of <b>tv</b>.
+ * All times are relative to tor_gettimeofday_cached_monotonic.
+ */
+void
+timer_schedule(tor_timer_t *t, const struct timeval *tv)
+{
+ const timeout_t when = tv_to_timeout(tv);
+ struct timeval now;
+ tor_gettimeofday_cached_monotonic(&now);
+ timer_advance_to_cur_time(&now);
+
+ /* Take the old timeout value. */
+ timeout_t to = timeouts_timeout(global_timeouts);
+
+ timeouts_add(global_timeouts, t, when);
+
+ /* Should we update the libevent timer? */
+ if (to <= when) {
+ return; /* we're already going to fire before this timer would trigger. */
+ }
+ libevent_timer_reschedule();
+}
+
+/**
+ * Cancel the timer <b>t</b> if it is currently scheduled. (It's okay to call
+ * this on an unscheduled timer.
+ */
+void
+timer_disable(tor_timer_t *t)
+{
+ timeouts_del(global_timeouts, t);
+ /* We don't reschedule the libevent timer here, since it's okay if it fires
+ * early. */
+}
+
diff --git a/src/common/timers.h b/src/common/timers.h
new file mode 100644
index 0000000000..594cf38a64
--- /dev/null
+++ b/src/common/timers.h
@@ -0,0 +1,22 @@
+/* Copyright (c) 2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_TIMERS_H
+#define TOR_TIMERS_H
+
+#include "orconfig.h"
+#include "testsupport.h"
+
+typedef struct timeout tor_timer_t;
+typedef void (*timer_cb_fn_t)(tor_timer_t *, void *, const struct timeval *);
+tor_timer_t *timer_new(timer_cb_fn_t cb, void *arg);
+void timer_set_cb(tor_timer_t *t, timer_cb_fn_t cb, void *arg);
+void timer_schedule(tor_timer_t *t, const struct timeval *delay);
+void timer_disable(tor_timer_t *t);
+void timer_free(tor_timer_t *t);
+
+void timers_initialize(void);
+void timers_shutdown(void);
+
+#endif
+
diff --git a/src/common/util.c b/src/common/util.c
index 008c682b3b..fa2953cc30 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -105,23 +105,6 @@
#endif
/* =====
- * Assertion helper.
- * ===== */
-/** Helper for tor_assert: report the assertion failure. */
-void
-tor_assertion_failed_(const char *fname, unsigned int line,
- const char *func, const char *expr)
-{
- char buf[256];
- log_err(LD_BUG, "%s:%u: %s: Assertion %s failed; aborting.",
- fname, line, func, expr);
- tor_snprintf(buf, sizeof(buf),
- "Assertion %s failed in %s at %s:%u",
- expr, func, fname, line);
- log_backtrace(LOG_ERR, LD_BUG, buf);
-}
-
-/* =====
* Memory management
* ===== */
#ifdef USE_DMALLOC
diff --git a/src/common/util.h b/src/common/util.h
index ebcf88b32d..814c8622a2 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -22,6 +22,7 @@
/* for the correct alias to struct stat */
#include <sys/stat.h>
#endif
+#include "util_bug.h"
#ifndef O_BINARY
#define O_BINARY 0
@@ -33,41 +34,6 @@
#define O_NOFOLLOW 0
#endif
-/* Replace assert() with a variant that sends failures to the log before
- * calling assert() normally.
- */
-#ifdef NDEBUG
-/* Nobody should ever want to build with NDEBUG set. 99% of our asserts will
- * be outside the critical path anyway, so it's silly to disable bug-checking
- * throughout the entire program just because a few asserts are slowing you
- * down. Profile, optimize the critical path, and keep debugging on.
- *
- * And I'm not just saying that because some of our asserts check
- * security-critical properties.
- */
-#error "Sorry; we don't support building with NDEBUG."
-#endif
-
-/* Sometimes we don't want to use assertions during branch coverage tests; it
- * leads to tons of unreached branches which in reality are only assertions we
- * didn't hit. */
-#if defined(TOR_UNIT_TESTS) && defined(DISABLE_ASSERTS_IN_UNIT_TESTS)
-#define tor_assert(a) STMT_BEGIN \
- (void)(a); \
- STMT_END
-#else
-/** Like assert(3), but send assertion failures to the log as well as to
- * stderr. */
-#define tor_assert(expr) STMT_BEGIN \
- if (PREDICT_UNLIKELY(!(expr))) { \
- tor_assertion_failed_(SHORT_FILE__, __LINE__, __func__, #expr); \
- abort(); \
- } STMT_END
-#endif
-
-void tor_assertion_failed_(const char *fname, unsigned int line,
- const char *func, const char *expr);
-
/* If we're building with dmalloc, we want all of our memory allocation
* functions to take an extra file/line pair of arguments. If not, not.
* We define DMALLOC_PARAMS to the extra parameters to insert in the
@@ -81,11 +47,6 @@ void tor_assertion_failed_(const char *fname, unsigned int line,
#define DMALLOC_ARGS
#endif
-/** Define this if you want Tor to crash when any problem comes up,
- * so you can get a coredump and track things down. */
-// #define tor_fragile_assert() tor_assert(0)
-#define tor_fragile_assert()
-
/* Memory management */
void *tor_malloc_(size_t size DMALLOC_PARAMS) ATTR_MALLOC;
void *tor_malloc_zero_(size_t size DMALLOC_PARAMS) ATTR_MALLOC;
diff --git a/src/common/util_bug.c b/src/common/util_bug.c
new file mode 100644
index 0000000000..e3e1d6df90
--- /dev/null
+++ b/src/common/util_bug.c
@@ -0,0 +1,53 @@
+/* Copyright (c) 2003, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file util_bug.c
+ **/
+
+#include "orconfig.h"
+#include "util_bug.h"
+#include "torlog.h"
+#include "backtrace.h"
+
+/** Helper for tor_assert: report the assertion failure. */
+void
+tor_assertion_failed_(const char *fname, unsigned int line,
+ const char *func, const char *expr)
+{
+ char buf[256];
+ log_err(LD_BUG, "%s:%u: %s: Assertion %s failed; aborting.",
+ fname, line, func, expr);
+ tor_snprintf(buf, sizeof(buf),
+ "Assertion %s failed in %s at %s:%u",
+ expr, func, fname, line);
+ log_backtrace(LOG_ERR, LD_BUG, buf);
+}
+
+/** Helper for tor_assert_nonfatal: report the assertion failure. */
+void
+tor_bug_occurred_(const char *fname, unsigned int line,
+ const char *func, const char *expr,
+ int once)
+{
+ char buf[256];
+ const char *once_str = once ?
+ " (Future instances of this warning will be silenced.)": "";
+ if (! expr) {
+ log_warn(LD_BUG, "%s:%u: %s: This line should not have been reached.%s",
+ fname, line, func, once_str);
+ tor_snprintf(buf, sizeof(buf),
+ "Line unexpectedly reached at %s at %s:%u",
+ func, fname, line);
+ } else {
+ log_warn(LD_BUG, "%s:%u: %s: Non-fatal assertion %s failed.%s",
+ fname, line, func, expr, once_str);
+ tor_snprintf(buf, sizeof(buf),
+ "Non-fatal assertion %s failed in %s at %s:%u",
+ expr, func, fname, line);
+ }
+ log_backtrace(LOG_WARN, LD_BUG, buf);
+}
+
diff --git a/src/common/util_bug.h b/src/common/util_bug.h
new file mode 100644
index 0000000000..36056aa4bd
--- /dev/null
+++ b/src/common/util_bug.h
@@ -0,0 +1,150 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2016, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file util_bug.h
+ **/
+
+#ifndef TOR_UTIL_BUG_H
+#define TOR_UTIL_BUG_H
+
+#include "orconfig.h"
+#include "compat.h"
+#include "testsupport.h"
+
+/* Replace assert() with a variant that sends failures to the log before
+ * calling assert() normally.
+ */
+#ifdef NDEBUG
+/* Nobody should ever want to build with NDEBUG set. 99% of our asserts will
+ * be outside the critical path anyway, so it's silly to disable bug-checking
+ * throughout the entire program just because a few asserts are slowing you
+ * down. Profile, optimize the critical path, and keep debugging on.
+ *
+ * And I'm not just saying that because some of our asserts check
+ * security-critical properties.
+ */
+#error "Sorry; we don't support building with NDEBUG."
+#endif
+
+/* Sometimes we don't want to use assertions during branch coverage tests; it
+ * leads to tons of unreached branches which in reality are only assertions we
+ * didn't hit. */
+#if defined(TOR_UNIT_TESTS) && defined(DISABLE_ASSERTS_IN_UNIT_TESTS)
+#define tor_assert(a) STMT_BEGIN \
+ (void)(a); \
+ STMT_END
+#else
+/** Like assert(3), but send assertion failures to the log as well as to
+ * stderr. */
+#define tor_assert(expr) STMT_BEGIN \
+ if (PREDICT_UNLIKELY(!(expr))) { \
+ tor_assertion_failed_(SHORT_FILE__, __LINE__, __func__, #expr); \
+ abort(); \
+ } STMT_END
+#endif
+
+#define tor_assert_unreached() tor_assert(0)
+
+/* Non-fatal bug assertions. The "unreached" variants mean "this line should
+ * never be reached." The "once" variants mean "Don't log a warning more than
+ * once".
+ *
+ * The 'BUG' macro checks a boolean condition and logs an error message if it
+ * is true. Example usage:
+ * if (BUG(x == NULL))
+ * return -1;
+ */
+
+#ifdef ALL_BUGS_ARE_FATAL
+#define tor_assert_nonfatal_unreached() tor_assert(0)
+#define tor_assert_nonfatal(cond) tor_assert((cond))
+#define tor_assert_nonfatal_unreached_once() tor_assert(0)
+#define tor_assert_nonfatal_once(cond) tor_assert((cond))
+#define BUG(cond) \
+ (PREDICT_UNLIKELY(cond) ? \
+ (tor_assertion_failed_(SHORT_FILE__,__LINE__,__func__,#cond), abort(), 1) \
+ : 0)
+#elif defined(TOR_UNIT_TESTS) && defined(DISABLE_ASSERTS_IN_UNIT_TESTS)
+#define tor_assert_nonfatal_unreached() STMT_NIL
+#define tor_assert_nonfatal(cond) ((void)(cond))
+#define tor_assert_nonfatal_unreached_once() STMT_NIL
+#define tor_assert_nonfatal_once(cond) ((void)(cond))
+#define BUG(cond) (PREDICT_UNLIKELY(cond) ? 1 : 0)
+#else /* Normal case, !ALL_BUGS_ARE_FATAL, !DISABLE_ASSERTS_IN_UNIT_TESTS */
+#define tor_assert_nonfatal_unreached() STMT_BEGIN \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, NULL, 0); \
+ STMT_END
+#define tor_assert_nonfatal(cond) STMT_BEGIN \
+ if (PREDICT_UNLIKELY(!(cond))) { \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 0); \
+ } \
+ STMT_END
+#define tor_assert_nonfatal_unreached_once() STMT_BEGIN \
+ static int warning_logged__ = 0; \
+ if (!warning_logged__) { \
+ warning_logged__ = 1; \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, NULL, 1); \
+ } \
+ STMT_END
+#define tor_assert_nonfatal_once(cond) STMT_BEGIN \
+ static int warning_logged__ = 0; \
+ if (!warning_logged__ && PREDICT_UNLIKELY(!(cond))) { \
+ warning_logged__ = 1; \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 1); \
+ } \
+ STMT_END
+#define BUG(cond) \
+ (PREDICT_UNLIKELY(cond) ? \
+ (tor_bug_occurred_(SHORT_FILE__,__LINE__,__func__,#cond,0), 1) \
+ : 0)
+#endif
+
+#ifdef __GNUC__
+#define IF_BUG_ONCE__(cond,var) \
+ if (({ \
+ static int var = 0; \
+ int bool_result = (cond); \
+ if (PREDICT_UNLIKELY(bool_result) && !var) { \
+ var = 1; \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 1); \
+ } \
+ PREDICT_UNLIKELY(bool_result); }))
+#else
+#define IF_BUG_ONCE__(cond,var) \
+ static int var = 0; \
+ if (PREDICT_UNLIKELY(cond)) ? \
+ (var ? 1 : \
+ (var=1, \
+ tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 1), \
+ 1)) \
+ : 0)
+#endif
+#define IF_BUG_ONCE_VARNAME_(a) \
+ warning_logged_on_ ## a ## __
+#define IF_BUG_ONCE_VARNAME__(a) \
+ IF_BUG_ONCE_VARNAME_(a)
+
+/** This macro behaves as 'if (bug(x))', except that it only logs its
+ * warning once, no matter how many times it triggers.
+ */
+
+#define IF_BUG_ONCE(cond) \
+ IF_BUG_ONCE__((cond), \
+ IF_BUG_ONCE_VARNAME__(__LINE__))
+
+/** Define this if you want Tor to crash when any problem comes up,
+ * so you can get a coredump and track things down. */
+// #define tor_fragile_assert() tor_assert_unreached(0)
+#define tor_fragile_assert() tor_assert_nonfatal_unreached_once()
+
+void tor_assertion_failed_(const char *fname, unsigned int line,
+ const char *func, const char *expr);
+void tor_bug_occurred_(const char *fname, unsigned int line,
+ const char *func, const char *expr,
+ int once);
+
+#endif
+