ABI: refuse non-matching ABI minor version on event registration

[lttng-ust.git] / liblttng-ust-ctl / ustctl.c

diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c
index 49ae3e6cf94dfc12f6ae32c176841d8a8e71cc79..5a7fa61fa17064be30a524a3c8dd04c28b7c1da6 100644 (file)
--- a/liblttng-ust-ctl/ustctl.c
+++ b/liblttng-ust-ctl/ustctl.c
@@ -32,6 +32,7 @@
 #include "../libringbuffer/frontend.h"
 #include "../liblttng-ust/wait.h"
 #include "../liblttng-ust/lttng-rb-clients.h"
+#include "../liblttng-ust/clock.h"
 
 /*
  * Number of milliseconds to retry before failing metadata writes on
@@ -942,8 +943,14 @@ error:
 
 /* Buffer operations */
 
+int ustctl_get_nr_stream_per_channel(void)
+{
+       return num_possible_cpus();
+}
+
 struct ustctl_consumer_channel *
-       ustctl_create_channel(struct ustctl_consumer_channel_attr *attr)
+       ustctl_create_channel(struct ustctl_consumer_channel_attr *attr,
+               const int *stream_fds, int nr_stream_fds)
 {
        struct ustctl_consumer_channel *chan;
        const char *transport_name;
@@ -995,7 +1002,8 @@ struct ustctl_consumer_channel *
                        attr->subbuf_size, attr->num_subbuf,
                        attr->switch_timer_interval,
                        attr->read_timer_interval,
-                       attr->uuid, attr->chan_id);
+                       attr->uuid, attr->chan_id,
+                       stream_fds, nr_stream_fds);
        if (!chan->chan) {
                goto chan_error;
        }
@@ -1333,6 +1341,8 @@ int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
        unsigned long sb_bindex;
        struct lttng_ust_lib_ring_buffer *buf;
        struct ustctl_consumer_channel *consumer_chan;
+       struct lttng_ust_lib_ring_buffer_backend_pages_shmp *barray_idx;
+       struct lttng_ust_lib_ring_buffer_backend_pages *pages;
 
        if (!stream)
                return -EINVAL;
@@ -1343,8 +1353,14 @@ int ustctl_get_mmap_read_offset(struct ustctl_consumer_stream *stream,
                return -EINVAL;
        sb_bindex = subbuffer_id_get_index(&chan->backend.config,
                                        buf->backend.buf_rsb.id);
-       *off = shmp(consumer_chan->chan->handle,
-               shmp_index(consumer_chan->chan->handle, buf->backend.array, sb_bindex)->shmp)->mmap_offset;
+       barray_idx = shmp_index(consumer_chan->chan->handle, buf->backend.array,
+                       sb_bindex);
+       if (!barray_idx)
+               return -EINVAL;
+       pages = shmp(consumer_chan->chan->handle, barray_idx->shmp);
+       if (!pages)
+               return -EINVAL;
+       *off = pages->mmap_offset;
        return 0;
 }
 
@@ -1510,6 +1526,8 @@ struct lttng_ust_client_lib_ring_buffer_client_cb *get_client_cb(
        struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
 
        chan = shmp(handle, buf->backend.chan);
+       if (!chan)
+               return NULL;
        config = &chan->backend.config;
        if (!config->cb_ptr)
                return NULL;
@@ -1638,6 +1656,22 @@ int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream,
        return client_cb->current_timestamp(buf, handle, ts);
 }
 
+#if defined(__x86_64__) || defined(__i386__)
+
+int ustctl_has_perf_counters(void)
+{
+       return 1;
+}
+
+#else
+
+int ustctl_has_perf_counters(void)
+{
+       return 0;
+}
+
+#endif
+
 /*
  * Returns 0 on success, negative error value on error.
  */
@@ -1703,6 +1737,17 @@ int ustctl_recv_reg_msg(int sock,
                return -LTTNG_UST_ERR_UNSUP_MAJOR;
        }
 
+       /*
+        * Addition of enumeration inside _ustclt_basic_type should have been
+        * marked as a breaking ABI change since it blows past the included
+        * padding hence result in bigger than expected struct. Refuse
+        * registration for non-matching minor version since only two minor
+        * versions exist for ust-2.7(6.0) and 2.8(6.1).
+        */
+       if (reg_msg.minor != LTTNG_UST_ABI_MINOR_VERSION) {
+               return -LTTNG_UST_ERR_UNSUP_MAJOR;
+       }
+
        return 0;
 }
 
@@ -1980,6 +2025,7 @@ static __attribute__((constructor))
 void ustctl_init(void)
 {
        init_usterr();
+       lttng_ust_clock_init();
        lttng_ring_buffer_metadata_client_init();
        lttng_ring_buffer_client_overwrite_init();
        lttng_ring_buffer_client_overwrite_rt_init();