Add application context support to lttng-ctl lttng_add_context

[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index 0dcd673ebaed084249afa638cd0dc00a9a52e2ca..03b74c0b74771a9d0be8158f152a617123799c47 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -4,6 +4,7 @@
  * Linux Trace Toolkit Control Library
  *
  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
  * This library is free software; you can redistribute it and/or modify it
  * under the terms of the GNU Lesser General Public License, version 2.1 only,
@@ -644,15 +645,18 @@ int lttng_add_context(struct lttng_handle *handle,
                struct lttng_event_context *ctx, const char *event_name,
                const char *channel_name)
 {
+       int ret;
+       size_t len = 0;
+       char *buf = NULL;
        struct lttcomm_session_msg lsm;
 
        /* Safety check. Both are mandatory. */
        if (handle == NULL || ctx == NULL) {
-               return -LTTNG_ERR_INVALID;
+               ret = -LTTNG_ERR_INVALID;
+               goto end;
        }
 
        memset(&lsm, 0, sizeof(lsm));
-
        lsm.cmd_type = LTTNG_ADD_CONTEXT;
 
        /* If no channel name, send empty string. */
@@ -665,13 +669,52 @@ int lttng_add_context(struct lttng_handle *handle,
        }
 
        lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
-
-       memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
-
        lttng_ctl_copy_string(lsm.session.name, handle->session_name,
                        sizeof(lsm.session.name));
 
-       return lttng_ctl_ask_sessiond(&lsm, NULL);
+       if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
+               size_t provider_len, ctx_len;
+               const char *provider_name = ctx->u.app_ctx.provider_name;
+               const char *ctx_name = ctx->u.app_ctx.ctx_name;
+
+               if (!provider_name || !ctx_name) {
+                       ret = -LTTNG_ERR_INVALID;
+                       goto end;
+               }
+
+               provider_len = strlen(provider_name);
+               if (provider_len == 0) {
+                       ret = -LTTNG_ERR_INVALID;
+                       goto end;
+               }
+               lsm.u.context.provider_name_len = provider_len;
+
+               ctx_len = strlen(ctx_name);
+               if (ctx_len == 0) {
+                       ret = -LTTNG_ERR_INVALID;
+                       goto end;
+               }
+               lsm.u.context.context_name_len = ctx_len;
+
+               len = provider_len + ctx_len;
+               buf = zmalloc(len);
+               if (!buf) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               memcpy(buf, provider_name, provider_len);
+               memcpy(buf + provider_len, ctx_name, ctx_len);
+       }
+       memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context));
+       /* Don't leak application addresses to the sessiond. */
+       lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
+       lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
+
+       ret = lttng_ctl_ask_sessiond_varlen(&lsm, buf, len, NULL);
+end:
+       free(buf);
+       return ret;
 }
 
 /*