Add destroy session feature

The destroy command is added. Some fixes were needed
for destroy_session function in ltt-sessiond and basic
handling of uuid.

Now, the whole chain of tools uses libuuid.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>

diff --git a/include/lttng/liblttngctl.h b/include/lttng/liblttngctl.h
index 3c084de323fba6481a9356b3ceae3e0a3525486a..b729f2b5b0c29f520fb5f4f7e3aa6ba047f45d1f 100644 (file)
--- a/include/lttng/liblttngctl.h
+++ b/include/lttng/liblttngctl.h
@@ -20,6 +20,7 @@
 #define _LIBLTTNGCTL_H
 
 #include <limits.h>
+#include <uuid/uuid.h>
 
 /* Default unix group name for tracing.
  */
@@ -41,7 +42,8 @@ struct lttng_session {
        char uuid[UUID_STR_LEN];
 };
 
-extern int lttng_create_session(char *name, char **session_id);
+extern int lttng_create_session(char *name, uuid_t *session_id);
+extern int lttng_destroy_session(uuid_t *uuid);
 extern int lttng_connect_sessiond(void);
 extern int lttng_set_tracing_group(const char *name);
 extern int lttng_check_session_daemon(void);

diff --git a/liblttngctl/liblttngctl.c b/liblttngctl/liblttngctl.c
index bd7dcb0c5b6f87cd146a8ceb2c5e064892a621ee..9afd6fda3239e0085c24ec433383ac2755019bd8 100644 (file)
--- a/liblttngctl/liblttngctl.c
+++ b/liblttngctl/liblttngctl.c
@@ -194,23 +194,40 @@ int lttng_ust_list_apps(pid_t **pids)
  *  Create a brand new session using name. Allocate
  *  the session_id param pointing to the UUID.
  */
-int lttng_create_session(char *name, char **session_id)
+int lttng_create_session(char *name, uuid_t *session_id)
 {
        int ret;
        char *uuid;
 
        strncpy(lsm.session_name, name, sizeof(lsm.session_name));
+       lsm.session_name[sizeof(lsm.session_name) - 1] = '\0';
 
        ret = ask_sessiond(LTTNG_CREATE_SESSION, NULL);
        if (ret < 0) {
                goto end;
        }
 
-       /* Allocate UUID string length */
-       uuid = malloc(UUID_STR_LEN);
+       uuid_copy(*session_id, llm.session_id);
 
-       strncpy(uuid, llm.session_id, UUID_STR_LEN);
-       *session_id = uuid;
+end:
+       return ret;
+}
+
+/*
+ *  lttng_destroy_session
+ *
+ *  Destroy session using name.
+ */
+int lttng_destroy_session(uuid_t *uuid)
+{
+       int ret;
+
+       uuid_copy(lsm.session_id, *uuid);
+
+       ret = ask_sessiond(LTTNG_DESTROY_SESSION, NULL);
+       if (ret < 0) {
+               goto end;
+       }
 
 end:
        return ret;

diff --git a/liblttsessiondcomm/liblttsessiondcomm.h b/liblttsessiondcomm/liblttsessiondcomm.h
index 56414063c6bacd70b79e50ae697774d61420129a..6d6290d0a455cf34e2ec6ed043bdb471864a63f3 100644 (file)
--- a/liblttsessiondcomm/liblttsessiondcomm.h
+++ b/liblttsessiondcomm/liblttsessiondcomm.h
@@ -85,7 +85,7 @@ enum lttcomm_return_code {
 struct lttcomm_session_msg {
        /* Common data to almost all command */
        enum lttcomm_command_type cmd_type;
-       char session_id[37];
+       uuid_t session_id;
        char trace_name[NAME_MAX];
        char session_name[NAME_MAX];
        pid_t pid;
@@ -125,7 +125,7 @@ struct lttcomm_session_msg {
 struct lttcomm_lttng_msg {
        enum lttcomm_command_type cmd_type;
        enum lttcomm_return_code ret_code;
-       char session_id[37];
+       uuid_t session_id;
        pid_t pid;
        char trace_name[NAME_MAX];
        unsigned int size_payload;

diff --git a/ltt-sessiond/ltt-sessiond.c b/ltt-sessiond/ltt-sessiond.c
index 2dcf62f4518b620a31bd3b674dab166b143c67b3..3590d7e444c685147cf74c3a2ece2e1de2831367 100644 (file)
--- a/ltt-sessiond/ltt-sessiond.c
+++ b/ltt-sessiond/ltt-sessiond.c
@@ -69,9 +69,10 @@ static void *thread_manage_clients(void *data);
 static void *thread_manage_apps(void *data);
 
 static int create_session(char *name, uuid_t *session_id);
-static void destroy_session(uuid_t session_id);
+static int destroy_session(uuid_t *uuid);
 
-static struct ltt_session *find_session(uuid_t session_id);
+static struct ltt_session *find_session_by_uuid(uuid_t session_id);
+static struct ltt_session *find_session_by_name(char *name);
 
 /* Variables */
 const char *progname;
@@ -302,13 +303,14 @@ error:
 }
 
 /*
- *     find_session
+ *     find_session_by_uuid
  *
  *     Return a ltt_session structure ptr that matches the uuid.
  */
-static struct ltt_session *find_session(uuid_t session_id)
+static struct ltt_session *find_session_by_uuid(uuid_t session_id)
 {
-       struct ltt_session *iter = NULL;
+       int found = 0;
+       struct ltt_session *iter;
 
        /* Sanity check for NULL session_id */
        if (uuid_is_null(session_id)) {
@@ -316,12 +318,41 @@ static struct ltt_session *find_session(uuid_t session_id)
        }
 
        cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
-               if (uuid_compare(iter->uuid, session_id)) {
+               if (uuid_compare(iter->uuid, session_id) == 0) {
+                       found = 1;
                        break;
                }
        }
 
 end:
+       if (!found) {
+               iter = NULL;
+       }
+       return iter;
+}
+
+/*
+ *     find_session_by_name
+ *
+ *     Return a ltt_session structure ptr that matches name.
+ *     If no session found, NULL is returned.
+ */
+static struct ltt_session *find_session_by_name(char *name)
+{
+       int found = 0;
+       struct ltt_session *iter;
+
+       cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
+               if (strncmp(iter->name, name, strlen(iter->name)) == 0) {
+                       found = 1;
+                       break;
+               }
+       }
+
+       if (!found) {
+               iter = NULL;
+       }
+
        return iter;
 }
 
@@ -330,22 +361,26 @@ end:
  *
  *  Delete session from the global session list
  *  and free the memory.
+ *
+ *  Return -1 if no session is found.
+ *  On success, return 1;
  */
-static void destroy_session(uuid_t session_id)
+static int destroy_session(uuid_t *uuid)
 {
-       struct ltt_session *iter = NULL;
+       int found = -1;
+       struct ltt_session *iter;
 
        cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
-               if (uuid_compare(iter->uuid, session_id)) {
+               if (uuid_compare(iter->uuid, *uuid) == 0) {
                        cds_list_del(&iter->list);
+                       free(iter);
+                       session_count--;
+                       found = 1;
                        break;
                }
        }
 
-       if (iter) {
-               free(iter);
-               session_count--;
-       }
+       return found;
 }
 
 /*
@@ -371,7 +406,7 @@ static int create_session(char *name, uuid_t *session_id)
                }
        } else {
                /* Generate session name based on the session count */
-               if (asprintf(&new_session->name, "%s%d", "auto", session_count) < 0) {
+               if (asprintf(&new_session->name, "%s%d", "lttng-", session_count) < 0) {
                        goto error;
                }
        }
@@ -456,11 +491,12 @@ static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_sessi
        llm->pid = lsm->pid;
 
        /* Manage uuid */
-       if (lsm->session_id != NULL) {
-               strncpy(llm->session_id, lsm->session_id, UUID_STR_LEN);
+       if (!uuid_is_null(lsm->session_id)) {
+               uuid_copy(llm->session_id, lsm->session_id);
        }
 
        strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name));
+       llm->trace_name[strlen(llm->trace_name) - 1] = '\0';
 }
 
 /*
@@ -526,29 +562,37 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
        switch (lsm->cmd_type) {
                case LTTNG_CREATE_SESSION:
                {
-                       uuid_t uuid;
-                       ret = create_session(lsm->session_name, &uuid);
+                       ret = create_session(lsm->session_name, &llm.session_id);
                        if (ret < 0) {
-                               goto error;
+                               goto end;
                        }
 
-                       uuid_unparse(uuid, llm.session_id);
-
                        buf_size = setup_data_buffer(&send_buf, 0, &llm);
                        if (buf_size < 0) {
                                ret = LTTCOMM_FATAL;
-                               goto error;
+                               goto end;
                        }
 
-                       goto send;
                        break;
                }
+               case LTTNG_DESTROY_SESSION:
+               {
+                       ret = destroy_session(&lsm->session_id);
+                       if (ret < 0) {
+                               ret = LTTCOMM_NO_SESS;
+                       } else {
+                               ret = LTTCOMM_OK;
+                       }
+
+                       /* No auxiliary data so only send the llm struct. */
+                       goto end;
+               }
                case UST_LIST_APPS:
                {
                        /* Stop right now if no apps */
                        if (traceable_app_count == 0) {
                                ret = LTTCOMM_NO_APPS;
-                               goto error;
+                               goto end;
                        }
 
                        /* Setup data buffer and details for transmission */
@@ -556,12 +600,11 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
                                        sizeof(pid_t) * traceable_app_count, &llm);
                        if (buf_size < 0) {
                                ret = LTTCOMM_FATAL;
-                               goto error;
+                               goto end;
                        }
 
                        get_list_apps((pid_t *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 
-                       goto send;
                        break;
                }
                case LTTNG_LIST_SESSIONS:
@@ -569,7 +612,7 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
                        /* Stop right now if no session */
                        if (session_count == 0) {
                                ret = LTTCOMM_NO_SESS;
-                               goto error;
+                               goto end;
                        }
 
                        /* Setup data buffer and details for transmission */
@@ -577,23 +620,21 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
                                        (sizeof(struct lttng_session) * session_count), &llm);
                        if (buf_size < 0) {
                                ret = LTTCOMM_FATAL;
-                               goto error;
+                               goto end;
                        }
 
                        get_list_sessions((struct lttng_session *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 
-                       goto send;
                        break;
                }
                default:
                {
                        /* Undefined command */
                        ret = LTTCOMM_UND;
-                       goto error;
+                       goto end;
                }
        }
 
-send:
        ret = send_unix_sock(sock, send_buf, buf_size);
 
        if (send_buf != NULL) {
@@ -602,13 +643,13 @@ send:
 
        return ret;
 
-error:
+end:
        /* Notify client of error */
        llm.ret_code = ret;
        llm.size_payload = 0;
        send_unix_sock(sock, (void*) &llm, sizeof(llm));
 
-       return -1;
+       return ret;
 }
 
 /*

diff --git a/lttng/lttng.c b/lttng/lttng.c
index b08ecfed8af6debe14aeff7d4f35eb691cc42cd5..169e70eb0ddeedf5d29ffbe57ffb4f8581b3990f 100644 (file)
--- a/lttng/lttng.c
+++ b/lttng/lttng.c
@@ -56,6 +56,7 @@ static int set_signal_handler(void);
 static int process_client_opt(void)
 {
        int ret;
+       uuid_t uuid;
 
        /* Connect to the session daemon */
        ret = lttng_connect_sessiond();
@@ -84,6 +85,14 @@ static int process_client_opt(void)
                }
        }
 
+       if (opt_destroy_session != NULL) {
+               uuid_parse(opt_destroy_session, uuid);
+               ret = lttng_destroy_session(&uuid);
+               if (ret < 0) {
+                       goto end;
+               }
+       }
+
        return 0;
 
 end:
@@ -100,15 +109,18 @@ end:
 static int process_opt_create_session(void)
 {
        int ret;
-       char *session_id;
+       uuid_t session_id;
+       char str_uuid[37];
 
        ret = lttng_create_session(opt_create_session, &session_id);
        if (ret < 0) {
                goto error;
        }
 
+       uuid_unparse(session_id, str_uuid);
+
        MSG("Session created:");
-       MSG("    %s (%s)", opt_create_session, session_id);
+       MSG("    %s (%s)", opt_create_session, str_uuid);
 
 error:
        return ret;

diff --git a/lttng/lttng.h b/lttng/lttng.h
index 1faa29d7979298f0cdcc36d7880b0171950b51ac..f9e75538c96d9213ac2220a76f0a149e4f35c601 100644 (file)
--- a/lttng/lttng.h
+++ b/lttng/lttng.h
@@ -30,6 +30,7 @@ extern char *opt_tracing_group;
 extern char *opt_session_name;
 extern char *opt_create_session;
 extern char *opt_sessiond_path;
+extern char *opt_destroy_session;
 extern int opt_list_apps;
 extern int opt_no_sessiond;
 extern int opt_list_session;

diff --git a/lttng/options.c b/lttng/options.c
index eb31108c446ea5f07f55838245a360ef8861e220..befeab54af83d8f34b07bb7673b0b19597ae9e7a 100644 (file)
--- a/lttng/options.c
+++ b/lttng/options.c
@@ -26,6 +26,7 @@ char *opt_tracing_group;
 char *opt_session_name;
 char *opt_create_session;
 char *opt_sessiond_path;
+char *opt_destroy_session;
 int opt_trace_kernel = 0;
 int opt_quiet = 0;
 int opt_verbose = 0;
@@ -51,6 +52,7 @@ static struct poptOption long_options[] = {
        {"no-sessiond",         0,              POPT_ARG_VAL,           &opt_no_sessiond, 1, 0},
        {"sessiond-path",       0,              POPT_ARG_STRING,        &opt_sessiond_path, 0, 0},
        {"list-session",        0,              POPT_ARG_VAL,           &opt_list_session, 1, 0},
+       {"destroy-session", 'd',        POPT_ARG_STRING,        &opt_destroy_session, 0, 0},
        {0, 0, 0, 0, 0, 0}
 };
 
@@ -74,8 +76,9 @@ static void usage(FILE *ofp)
        fprintf(ofp, "Session options:\n");
        fprintf(ofp, "  -c, --create-session NAME    Create a new session\n");
        fprintf(ofp, "      --list-session           List all available sessions\n");
-       //fprintf(ofp, "      --session [NAME]       Specify tracing session. If no NAME is given\n");
-       //fprintf(ofp, "                             or option is ommited, a session will be created\n");
+       fprintf(ofp, "      --session [NAME]         Specify tracing session. If no NAME is given\n");
+       fprintf(ofp, "                               or option is ommited, a session will be created\n");
+       fprintf(ofp, "  -d, --destroy-session=NAME   Destroy the session specified by NAME\n");
        fprintf(ofp, "\n");
        fprintf(ofp, "Tracing options:\n");
        //fprintf(ofp, "      --kernel               Enable kernel tracing\n");