#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
+#include <dlfcn.h>
#include <urcu/arch.h>
#include <lttng/urcu/urcu-ust.h>
}
}
+/*
+ * Use a symbol of the previous ABI to detect if liblttng-ust-tracepoint.so.0
+ * is loaded in the current process.
+ */
+#define LTTNG_UST_TRACEPOINT_SONAME_0_SYM "tracepoint_unregister_lib"
+
+static
+void lttng_ust_tracepoint_check_soname_0(void)
+{
+ if (!dlsym(RTLD_DEFAULT, LTTNG_UST_TRACEPOINT_SONAME_0_SYM))
+ return;
+
+ CRIT("Incompatible library ABIs detected within the same process. "
+ "The process is likely linked against different major soname of LTTng-UST which is unsupported. "
+ "The detection was triggered by lookup of ABI 0 symbol \"%s\" in the Global Symbol Table\n",
+ LTTNG_UST_TRACEPOINT_SONAME_0_SYM);
+}
+
+/*
+ * Expose a canary symbol of the previous ABI to ensure we catch uses of a
+ * liblttng-ust-tracepoint.so.0 dlopen'd after .so.1 has been loaded. Use a
+ * different symbol than the detection code to ensure we don't detect ourself.
+ */
+int tracepoint_register_lib(void *arg0 __attribute__((unused)), int arg1 __attribute__((unused)));
+int tracepoint_register_lib(void *arg0 __attribute__((unused)), int arg1 __attribute__((unused)))
+{
+ CRIT("Incompatible library ABIs detected within the same process. "
+ "The process is likely linked against different major soname of LTTng-UST which is unsupported. "
+ "The detection was triggered by canary symbol \"%s\"\n", __func__);
+
+ return -1;
+}
+
/**
* lttng_ust_tracepoint_provider_register - Connect a probe to a tracepoint
* @name: tracepoint provider name
void *old;
int ret = 0;
+ /*
+ * Check if we find a symbol of the previous ABI in the current process
+ * as different ABIs of liblttng-ust can't co-exist in a process. If we
+ * do so, emit a critical log message which will also abort if the
+ * LTTNG_UST_ABORT_ON_CRITICAL environment variable is set.
+ */
+ lttng_ust_tracepoint_check_soname_0();
+
DBG("Registering probe to tracepoint \"%s:%s\"", provider_name, event_name);
pthread_mutex_lock(&tracepoint_mutex);