Fix: race between lttng-ust getenv() and application setenv()

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

diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c
index bbf47381e538d2021c2f3a57776549bd4de06f82..4067758254438c45e2db0363ba55ee8d5d2f08a0 100644 (file)
--- a/liblttng-ust-ctl/ustctl.c
+++ b/liblttng-ust-ctl/ustctl.c
@@ -18,6 +18,7 @@
 
 #define _GNU_SOURCE
 #include <string.h>
+#include <lttng/ust-config.h>
 #include <lttng/ust-ctl.h>
 #include <lttng/ust-abi.h>
 #include <lttng/ust-events.h>
@@ -212,34 +213,86 @@ int ustctl_create_event(int sock, struct lttng_ust_event *ev,
        return 0;
 }
 
-int ustctl_add_context(int sock, struct lttng_ust_context *ctx,
+int ustctl_add_context(int sock, struct lttng_ust_context_attr *ctx,
                struct lttng_ust_object_data *obj_data,
                struct lttng_ust_object_data **_context_data)
 {
        struct ustcomm_ust_msg lum;
        struct ustcomm_ust_reply lur;
-       struct lttng_ust_object_data *context_data;
+       struct lttng_ust_object_data *context_data = NULL;
+       char *buf = NULL;
+       size_t len;
        int ret;
 
-       if (!obj_data || !_context_data)
-               return -EINVAL;
+       if (!obj_data || !_context_data) {
+               ret = -EINVAL;
+               goto end;
+       }
 
        context_data = zmalloc(sizeof(*context_data));
-       if (!context_data)
-               return -ENOMEM;
+       if (!context_data) {
+               ret = -ENOMEM;
+               goto end;
+       }
        context_data->type = LTTNG_UST_OBJECT_TYPE_CONTEXT;
        memset(&lum, 0, sizeof(lum));
        lum.handle = obj_data->handle;
        lum.cmd = LTTNG_UST_CONTEXT;
-       lum.u.context = *ctx;
-       ret = ustcomm_send_app_cmd(sock, &lum, &lur);
-       if (ret) {
-               free(context_data);
-               return ret;
+
+       lum.u.context.ctx = ctx->ctx;
+       switch (ctx->ctx) {
+       case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
+               lum.u.context.u.perf_counter = ctx->u.perf_counter;
+               break;
+       case LTTNG_UST_CONTEXT_APP_CONTEXT:
+       {
+               size_t provider_name_len = strlen(
+                               ctx->u.app_ctx.provider_name) + 1;
+               size_t ctx_name_len = strlen(ctx->u.app_ctx.ctx_name) + 1;
+
+               lum.u.context.u.app_ctx.provider_name_len = provider_name_len;
+               lum.u.context.u.app_ctx.ctx_name_len = ctx_name_len;
+
+               len = provider_name_len + ctx_name_len;
+               buf = zmalloc(len);
+               if (!buf) {
+                       ret = -ENOMEM;
+                       goto end;
+               }
+               memcpy(buf, ctx->u.app_ctx.provider_name,
+                               provider_name_len);
+               memcpy(buf + provider_name_len, ctx->u.app_ctx.ctx_name,
+                               ctx_name_len);
+               break;
+       }
+       default:
+               break;
+       }
+       ret = ustcomm_send_app_msg(sock, &lum);
+       if (ret)
+               goto end;
+       if (buf) {
+               /* send var len ctx_name */
+               ret = ustcomm_send_unix_sock(sock, buf, len);
+               if (ret < 0) {
+                       goto end;
+               }
+               if (ret != len) {
+                       ret = -EINVAL;
+                       goto end;
+               }
+       }
+       ret = ustcomm_recv_app_reply(sock, &lur, lum.handle, lum.cmd);
+       if (ret < 0) {
+               goto end;
        }
        context_data->handle = -1;
        DBG("Context created successfully");
        *_context_data = context_data;
+       context_data = NULL;
+end:
+       free(context_data);
+       free(buf);
        return ret;
 }
 
@@ -1656,7 +1709,41 @@ 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_get_sequence_number(struct ustctl_consumer_stream *stream,
+               uint64_t *seq)
+{
+       struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
+       struct lttng_ust_lib_ring_buffer *buf;
+       struct lttng_ust_shm_handle *handle;
+
+       if (!stream || !seq)
+               return -EINVAL;
+       buf = stream->buf;
+       handle = stream->chan->chan->handle;
+       client_cb = get_client_cb(buf, handle);
+       if (!client_cb || !client_cb->sequence_number)
+               return -ENOSYS;
+       return client_cb->sequence_number(buf, handle, seq);
+}
+
+int ustctl_get_instance_id(struct ustctl_consumer_stream *stream,
+               uint64_t *id)
+{
+       struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb;
+       struct lttng_ust_lib_ring_buffer *buf;
+       struct lttng_ust_shm_handle *handle;
+
+       if (!stream || !id)
+               return -EINVAL;
+       buf = stream->buf;
+       handle = stream->chan->chan->handle;
+       client_cb = get_client_cb(buf, handle);
+       if (!client_cb)
+               return -ENOSYS;
+       return client_cb->instance_id(buf, handle, id);
+}
+
+#ifdef LTTNG_UST_HAVE_PERF_EVENT
 
 int ustctl_has_perf_counters(void)
 {
@@ -2097,10 +2184,28 @@ int ustctl_reply_register_channel(int sock,
        return 0;
 }
 
+/* Regenerate the statedump. */
+int ustctl_regenerate_statedump(int sock, int handle)
+{
+       struct ustcomm_ust_msg lum;
+       struct ustcomm_ust_reply lur;
+       int ret;
+
+       memset(&lum, 0, sizeof(lum));
+       lum.handle = handle;
+       lum.cmd = LTTNG_UST_SESSION_STATEDUMP;
+       ret = ustcomm_send_app_cmd(sock, &lum, &lur);
+       if (ret)
+               return ret;
+       DBG("Regenerated statedump for handle %u", handle);
+       return 0;
+}
+
 static __attribute__((constructor))
 void ustctl_init(void)
 {
        init_usterr();
+       lttng_ust_getenv_init();        /* Needs init_usterr() to be completed. */
        lttng_ust_clock_init();
        lttng_ring_buffer_metadata_client_init();
        lttng_ring_buffer_client_overwrite_init();