Mi destroy command: support and validation

Function destroy_session now take a session as argument. It simplifies the mi
support and give further information on the destroyed session.

Regular output is not affected but the refactoring. We could add the
supplementary information for regular printing if wanted.

Signed-off-by: Jonathan Rajotte Julien <jonathan.r.julien@gmail.com>

diff --git a/src/bin/lttng/commands/destroy.c b/src/bin/lttng/commands/destroy.c
index 26548b9e153521f1b74b2d5c10d44968e7179744..50d5bb441a4476e8624a3cbfba095adaf2724d1a 100644 (file)
--- a/src/bin/lttng/commands/destroy.c
+++ b/src/bin/lttng/commands/destroy.c
@@ -26,11 +26,15 @@
 
 #include "../command.h"
 
+#include <common/mi-lttng.h>
 #include <common/sessiond-comm/sessiond-comm.h>
 
 static char *opt_session_name;
 static int opt_destroy_all;
 
+/* Mi writer */
+static struct mi_writer *writer;
+
 enum {
        OPT_HELP = 1,
        OPT_LIST_OPTIONS,
@@ -67,15 +71,15 @@ static void usage(FILE *ofp)
  * Unregister the provided session to the session daemon. On success, removes
  * the default configuration.
  */
-static int destroy_session(const char *session_name)
+static int destroy_session(struct lttng_session *session)
 {
        int ret;
 
-       ret = lttng_destroy_session(session_name);
+       ret = lttng_destroy_session(session->name);
        if (ret < 0) {
                switch (-ret) {
                case LTTNG_ERR_SESS_NOT_FOUND:
-                       WARN("Session name %s not found", session_name);
+                       WARN("Session name %s not found", session->name);
                        break;
                default:
                        ERR("%s", lttng_strerror(ret));
@@ -84,8 +88,17 @@ static int destroy_session(const char *session_name)
                goto error;
        }
 
-       MSG("Session %s destroyed", session_name);
+       MSG("Session %s destroyed", session->name);
        config_destroy_default();
+
+       if (lttng_opt_mi) {
+               ret = mi_lttng_session(writer, session, 0);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto error;
+               }
+       }
+
        ret = CMD_SUCCESS;
 error:
        return ret;
@@ -96,12 +109,10 @@ error:
  *
  * Call destroy_sessions for each registered sessions
  */
-static int destroy_all_sessions()
+static int destroy_all_sessions(struct lttng_session *sessions, int count)
 {
-       int count, i, ret = CMD_SUCCESS;
-       struct lttng_session *sessions;
+       int i, ret = CMD_SUCCESS;
 
-       count = lttng_list_sessions(&sessions);
        if (count == 0) {
                MSG("No session found, nothing to do.");
        } else if (count < 0) {
@@ -110,7 +121,7 @@ static int destroy_all_sessions()
        }
 
        for (i = 0; i < count; i++) {
-               ret = destroy_session(sessions[i].name);
+               ret = destroy_session(&sessions[i]);
                if (ret < 0) {
                        goto error;
                }
@@ -125,10 +136,14 @@ error:
 int cmd_destroy(int argc, const char **argv)
 {
        int opt;
-       int ret = CMD_SUCCESS;
+       int ret = CMD_SUCCESS , i, command_ret = CMD_SUCCESS, success = 1;
        static poptContext pc;
        char *session_name = NULL;
 
+       struct lttng_session *sessions;
+       int count;
+       int found;
+
        pc = poptGetContext(NULL, argc, argv, long_options, 0);
        poptReadDefaultConfig(pc, 0);
 
@@ -148,39 +163,127 @@ int cmd_destroy(int argc, const char **argv)
                goto end;
        }
 
-       /* TODO: mi support */
+       /* Mi preparation */
        if (lttng_opt_mi) {
-               ret = -LTTNG_ERR_MI_NOT_IMPLEMENTED;
-               ERR("mi option not supported");
-               goto end;
+               writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
+               if (!writer) {
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto end;
+               }
+
+               /* Open command element */
+               ret = mi_lttng_writer_command_open(writer,
+                               mi_lttng_element_command_destroy);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto end;
+               }
+
+               /* Open output element */
+               ret = mi_lttng_writer_open_element(writer,
+                               mi_lttng_element_command_output);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto end;
+               }
+
+               /* For validation and semantic purpose we open a sessions element */
+               ret = mi_lttng_sessions_open(writer);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto end;
+               }
+       }
+
+       /* Recuperate all sessions for further operation */
+       count = lttng_list_sessions(&sessions);
+       if (count < 0) {
+               command_ret = count;
+               success = 0;
+               goto mi_closing;
        }
 
        /* Ignore session name in case all sessions are to be destroyed */
        if (opt_destroy_all) {
-               ret = destroy_all_sessions();
-               goto end;
-       }
+               command_ret = destroy_all_sessions(sessions, count);
+               if (command_ret) {
+                       success = 0;
+               }
+       } else {
+               opt_session_name = (char *) poptGetArg(pc);
+
+               if (opt_session_name == NULL) {
+                       /* No session name specified, lookup default */
+                       session_name = get_session_name();
+                       if (session_name == NULL) {
+                               command_ret = CMD_ERROR;
+                               success = 0;
+                               goto mi_closing;
+                       }
+               } else {
+                       session_name = opt_session_name;
+               }
 
-       opt_session_name = (char *) poptGetArg(pc);
+               /* Find the corresponding lttng_session struct */
+               found = 0;
+               for (i = 0; i < count; i++) {
+                       if (strncmp(sessions[i].name, session_name, NAME_MAX) == 0) {
+                               found = 1;
+                               command_ret = destroy_session(&sessions[i]);
+                               if (command_ret) {
+                                       success = 0;
+                               }
 
-       if (opt_session_name == NULL) {
-               /* No session name specified, lookup default */
-               session_name = get_session_name();
-               if (session_name == NULL) {
+                       }
+               }
+
+               if (!found) {
+                       ERR("Session name %s not found", session_name);
+                       command_ret = LTTNG_ERR_SESS_NOT_FOUND;
+                       success = 0;
+                       goto mi_closing;
+               }
+       }
+
+mi_closing:
+       /* Mi closing */
+       if (lttng_opt_mi) {
+               /* Close sessions and output element element */
+               ret = mi_lttng_close_multi_element(writer, 2);
+               if (ret) {
                        ret = CMD_ERROR;
                        goto end;
                }
-       } else {
-               session_name = opt_session_name;
-       }
 
-       ret = destroy_session(session_name);
+               /* Success ? */
+               ret = mi_lttng_writer_write_element_bool(writer,
+                               mi_lttng_element_command_success, success);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto end;
+               }
 
+               /* Command element close */
+               ret = mi_lttng_writer_command_close(writer);
+               if (ret) {
+                       ret = CMD_ERROR;
+                       goto end;
+               }
+       }
 end:
+       /* Mi clean-up */
+       if (writer && mi_lttng_writer_destroy(writer)) {
+               /* Preserve original error code */
+               ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
+       }
+
        if (opt_session_name == NULL) {
                free(session_name);
        }
 
+       /* Overwrite ret if an error occurred during destroy_session/all */
+       ret = command_ret ? command_ret : ret;
+
        poptFreeContext(pc);
        return ret;
 }

diff --git a/src/common/mi-lttng.c b/src/common/mi-lttng.c
index 0994678a334377faa00ca8c75899dcc560c7084a..15deeb21ac64f6de1b214882f8a7f89fc7798548 100644 (file)
--- a/src/common/mi-lttng.c
+++ b/src/common/mi-lttng.c
@@ -33,6 +33,7 @@ const char * const mi_lttng_element_command_load = "load";
 const char * const mi_lttng_element_command_start = "start";
 const char * const mi_lttng_element_command_stop = "stop";
 const char * const mi_lttng_element_command_create = "create";
+const char * const mi_lttng_element_command_destroy = "destroy";
 const char * const mi_lttng_element_command_output = "output";
 const char * const mi_lttng_element_command_success = "success";
 

diff --git a/src/common/mi-lttng.h b/src/common/mi-lttng.h
index 2176b09ad76d70e16cd94863dc6dd6aba08af0cf..0f263fc5a69710bfc96efa5e7812d6a20c33bece 100644 (file)
--- a/src/common/mi-lttng.h
+++ b/src/common/mi-lttng.h
@@ -55,6 +55,7 @@ const char * const mi_lttng_element_command_load;
 const char * const mi_lttng_element_command_stop;
 const char * const mi_lttng_element_command_start;
 const char * const mi_lttng_element_command_create;
+const char * const mi_lttng_element_command_destroy;
 const char * const mi_lttng_element_command_output;
 const char * const mi_lttng_element_command_success;
 

diff --git a/src/common/mi_lttng.xsd b/src/common/mi_lttng.xsd
index ce472a3860262e7e9e487c59bcd69adf6e8c3e36..76e9a152ef18fd85127d52169f16bc73235fed76 100644 (file)
--- a/src/common/mi_lttng.xsd
+++ b/src/common/mi_lttng.xsd
@@ -330,6 +330,7 @@ THE SOFTWARE.
                        <xs:enumeration value="load" />
                        <xs:enumeration value="start" />
                        <xs:enumeration value="stop" />
+                       <xs:enumeration value="destroy" />
                </xs:restriction>
        </xs:simpleType>