diff --git a/ChangeLog b/ChangeLog
index 7b09d1904ae32e700b02d5900f42ed3c5fe0d03e..22bc33b9d9cc0006153a20acea67b223f3bb27b3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,11 @@ Changes in version 0.2.1.11-alpha - 2009-01-??
keys in those obsolete descriptors when building circuits. Bugfix
on 0.2.0.x. Fixes bug 887.
+ o Minor features:
+ - Try to make sure that the version of Libevent we're running with
+ is binary-compatible with the one we built with. May address bug
+ 897 and others.
+
o Minor bugfixes:
- Make outbound DNS packets respect the OutboundBindAddress setting.
Fixes the bug part of bug 798. Bugfix on 0.1.2.2-alpha.
diff --git a/configure.in b/configure.in
index aa59e776a51eaad2cea3449b3bbfc55dbabf1479..8cd44288533135c4efcd0eebd619709f9d3dfb9e 100644
--- a/configure.in
+++ b/configure.in
@@ -264,6 +264,10 @@ LIBS="-levent $TOR_LIB_WS32 $LIBS"
LDFLAGS="$TOR_LDFLAGS_libevent $LDFLAGS"
CPPFLAGS="$TOR_CPPFLAGS_libevent $CPPFLAGS"
AC_CHECK_FUNCS(event_get_version event_get_method event_set_log_callback)
+AC_CHECK_MEMBERS([struct event.min_heap_idx], , ,
+[#include <event.h>
+])
+
LIBS="$save_LIBS"
LDFLAGS="$save_LDFLAGS"
CPPFLAGS="$save_CPPFLAGS"
diff --git a/src/or/config.c b/src/or/config.c
index f733c362f7617f9eb0a20b96de23b358b58bfb35..02b9793737c1d2a44e9fa8e6d78cc2c4aafa4e1d 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -702,10 +702,12 @@ typedef enum {
/* Note: we compare these, so it's important that "old" precede everything,
* and that "other" come last. */
LE_OLD=0, LE_10C, LE_10D, LE_10E, LE_11, LE_11A, LE_11B, LE_12, LE_12A,
- LE_13, LE_13A, LE_13B, LE_13C, LE_13D,
+ LE_13, LE_13A, LE_13B, LE_13C, LE_13D, LE_13E,
+ LE_140, LE_141, LE_142, LE_143, LE_144, LE_145, LE_146, LE_147, LE_148,
+ LE_1499,
LE_OTHER
} le_version_t;
-static le_version_t decode_libevent_version(void);
+static le_version_t decode_libevent_version(const char *v, int *bincompat_out);
#if defined(HAVE_EVENT_GET_VERSION) && defined(HAVE_EVENT_GET_METHOD)
static void check_libevent_version(const char *m, int server);
#endif
@@ -4741,10 +4743,71 @@ init_libevent(void)
*/
suppress_libevent_log_msg("Function not implemented");
#ifdef __APPLE__
- if (decode_libevent_version() < LE_11B) {
+ if (decode_libevent_version(event_get_version()) < LE_11B) {
setenv("EVENT_NOKQUEUE","1",1);
}
#endif
+
+ /* In libevent versions before 2.0, it's hard to keep binary compatibility
+ * between upgrades, and unpleasant to detect when the version we compiled
+ * against is unlike the version we have linked against. Here's how. */
+#if defined(_EVENT_VERSION) && defined(HAVE_EVENT_GET_VERSION)
+ /* We have a header-file version and a function-call version. Easy. */
+ if (strcmp(_EVENT_VERSION, event_get_version())) {
+ int compat1 = -1, compat2 = -1;
+ int verybad, prettybad ;
+ decode_libevent_version(_EVENT_VERSION, &compat1);
+ decode_libevent_version(event_get_version(), &compat2);
+ verybad = compat1 != compat2;
+ prettybad = (compat1 == -1 || compat2 == -1) && compat1 != compat2;
+
+ log(verybad ? LOG_WARN : (prettybad ? LOG_NOTICE : LOG_INFO),
+ LD_GENERAL, "We were compiled with headers from version %s "
+ "of Libevent, but we're using a Libevent library that says it's "
+ "version %s.", _EVENT_VERSION, event_get_version());
+ if (verybad)
+ log_warn(LD_GENERAL, "This will almost certainly make Tor crash.");
+ else if (prettybad)
+ log_notice(LD_GENERAL, "If Tor crashes, this might be why.");
+ else
+ log_info(LD_GENERAL, "I think these versions are binary-compatible.");
+ }
+#elif defined(HAVE_EVENT_GET_VERSION)
+ /* event_get_version but no _EVENT_VERSION. We might be in 1.4.0-beta or
+ earlier, where that's normal. To see whether we were compiled with an
+ earlier version, let's see whether the struct event defines MIN_HEAP_IDX.
+ */
+#ifdef HAVE_STRUCT_EVENT_MIN_HEAP_IDX
+ /* The header files are 1.4.0-beta or later. If the version is not
+ * 1.4.0-beta, we are incompatible. */
+ {
+ if (strcmp(event_get_version(), "1.4.0-beta")) {
+ log_warn(LD_GENERAL, "It's a little hard to tell, but you seem to have "
+ "Libevent 1.4.0-beta header files, whereas you have linked "
+ "against Libevent %s. This will probably make Tor crash.",
+ event_get_version());
+ }
+ }
+#else
+ /* Our headers are 1.3e or earlier. If the library version is not 1.4.x or
+ later, we're probably fine. */
+ {
+ const char *v = event_get_version();
+ if ((v[0] == '1' && v[2] == '.' && v[3] > '3') || v[0] > '1') {
+ log_warn(LD_GENERAL, "It's a little hard to tell, but you seem to have "
+ "Libevent header file from 1.3e or earlier, whereas you have "
+ "linked against Libevent %s. This will probably make Tor "
+ "crash.", event_get_version());
+ }
+ }
+#endif
+
+#elif defined(_EVENT_VERSION)
+#warn "_EVENT_VERSION is defined but not get_event_version(): Libevent is odd."
+#else
+ /* Your libevent is ancient. */
+#endif
+
event_init();
suppress_libevent_log_msg(NULL);
#if defined(HAVE_EVENT_GET_VERSION) && defined(HAVE_EVENT_GET_METHOD)
@@ -4763,44 +4826,60 @@ init_libevent(void)
#endif
}
-#if defined(HAVE_EVENT_GET_VERSION) && defined(HAVE_EVENT_GET_METHOD)
/** Table mapping return value of event_get_version() to le_version_t. */
static const struct {
- const char *name; le_version_t version;
+ const char *name; le_version_t version; int bincompat;
} le_version_table[] = {
/* earlier versions don't have get_version. */
- { "1.0c", LE_10C },
- { "1.0d", LE_10D },
- { "1.0e", LE_10E },
- { "1.1", LE_11 },
- { "1.1a", LE_11A },
- { "1.1b", LE_11B },
- { "1.2", LE_12 },
- { "1.2a", LE_12A },
- { "1.3", LE_13 },
- { "1.3a", LE_13A },
- { "1.3b", LE_13B },
- { "1.3c", LE_13C },
- { "1.3d", LE_13D },
- { NULL, LE_OTHER }
+ { "1.0c", LE_10C, 1},
+ { "1.0d", LE_10D, 1},
+ { "1.0e", LE_10E, 1},
+ { "1.1", LE_11, 1 },
+ { "1.1a", LE_11A, 1 },
+ { "1.1b", LE_11B, 1 },
+ { "1.2", LE_12, 1 },
+ { "1.2a", LE_12A, 1 },
+ { "1.3", LE_13, 1 },
+ { "1.3a", LE_13A, 1 },
+ { "1.3b", LE_13B, 1 },
+ { "1.3c", LE_13C, 1 },
+ { "1.3d", LE_13D, 1 },
+ { "1.3e", LE_13E, 1 },
+ { "1.4.0-beta", LE_140, 2 },
+ { "1.4.1-beta", LE_141, 2 },
+ { "1.4.2-rc", LE_142, 2 },
+ { "1.4.3-stable", LE_143, 2 },
+ { "1.4.4-stable", LE_144, 2 },
+ { "1.4.5-stable", LE_145, 2 },
+ { "1.4.6-stable", LE_146, 2 },
+ { "1.4.7-stable", LE_147, 2 },
+ { "1.4.8-stable", LE_148, 2 },
+ { "1.4.99-trunk", LE_1499, 3 },
+ { NULL, LE_OTHER, 0 }
};
/** Return the le_version_t for the current version of libevent. If the
* version is very new, return LE_OTHER. If the version is so old that it
* doesn't support event_get_version(), return LE_OLD. */
static le_version_t
-decode_libevent_version(void)
+decode_libevent_version(const char *v, int *bincompat_out)
{
- const char *v = event_get_version();
int i;
for (i=0; le_version_table[i].name; ++i) {
if (!strcmp(le_version_table[i].name, v)) {
+ if (bincompat_out)
+ *bincompat_out = le_version_table[i].bincompat;
return le_version_table[i].version;
}
}
+ if (v[0] != '1' && bincompat_out)
+ *bincompat_out = 100;
+ else if (!strcmpstart(v, "1.4") && bincompat_out)
+ *bincompat_out = 2;
return LE_OTHER;
}
+#if defined(HAVE_EVENT_GET_VERSION) && defined(HAVE_EVENT_GET_METHOD)
/**
* Compare the given libevent method and version to a list of versions
* which are known not to work. Warn the user as appropriate.
@@ -4814,7 +4893,7 @@ check_libevent_version(const char *m, int server)
const char *badness = NULL;
const char *sad_os = "";
- version = decode_libevent_version();
+ version = decode_libevent_version(v, NULL);
/* XXX Would it be worthwhile disabling the methods that we know
* are buggy, rather than just warning about them and then proceeding
@@ -4888,12 +4967,6 @@ check_libevent_version(const char *m, int server)
}
}
-#else
-static le_version_t
-decode_libevent_version(void)
-{
- return LE_OLD;
-}
#endif
/** Return the persistent state struct for this Tor. */