Add create session feature

Add create session command to liblttngctl, lttng and
session daemon.

Fix a major bug with send data buffer having the wrong
pointer arithmetic and thus failing with memcpy.

Add -fno-strict-aliasing to the global CFLAGS.

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

diff --git a/configure.ac b/configure.ac
index bbd5914454c9738a4294a07740b41c07a46aa323..acf80176bb0ee27ac6b3a0b4bb35cb2eebb45247 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -38,7 +38,7 @@ AC_CHECK_DECL([cds_list_add], [],
        [AC_MSG_ERROR([liburcu 0.5.4 or newer is needed])], [[#include <urcu/list.h>]]
 )
 
-CFLAGS="-Wall $CFLAGS -g"
+CFLAGS="-Wall $CFLAGS -g -fno-strict-aliasing"
 
 AC_PROG_CC
 AC_PROG_LIBTOOL

diff --git a/include/lttng/liblttngctl.h b/include/lttng/liblttngctl.h
index 7d2bb88623171eec2a2dacd0e36249628ae42faa..3c084de323fba6481a9356b3ceae3e0a3525486a 100644 (file)
--- a/include/lttng/liblttngctl.h
+++ b/include/lttng/liblttngctl.h
@@ -41,7 +41,7 @@ struct lttng_session {
        char uuid[UUID_STR_LEN];
 };
 
-extern int lttng_create_session(const char *name, char *session_id);
+extern int lttng_create_session(char *name, char **session_id);
 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 fda45ae10d2bc423dea61b94f3a2521c5c074b0c..bd7dcb0c5b6f87cd146a8ceb2c5e064892a621ee 100644 (file)
--- a/liblttngctl/liblttngctl.c
+++ b/liblttngctl/liblttngctl.c
@@ -35,6 +35,7 @@ static char sessiond_sock_path[PATH_MAX];
 
 /* Communication structure to ltt-sessiond */
 static struct lttcomm_session_msg lsm;
+static struct lttcomm_lttng_msg llm;
 
 /* Prototypes */
 static int check_tracing_group(const char *grp_name);
@@ -109,7 +110,6 @@ static int ask_sessiond(enum lttcomm_command_type lct, void **buf)
        int ret;
        size_t size;
        void *data = NULL;
-       struct lttcomm_lttng_msg llm;
 
        lsm.cmd_type = lct;
 
@@ -188,6 +188,34 @@ int lttng_ust_list_apps(pid_t **pids)
        return ret / sizeof(pid_t);
 }
 
+/*
+ *  lttng_create_session
+ *
+ *  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 ret;
+       char *uuid;
+
+       strncpy(lsm.session_name, name, sizeof(lsm.session_name));
+
+       ret = ask_sessiond(LTTNG_CREATE_SESSION, NULL);
+       if (ret < 0) {
+               goto end;
+       }
+
+       /* Allocate UUID string length */
+       uuid = malloc(UUID_STR_LEN);
+
+       strncpy(uuid, llm.session_id, UUID_STR_LEN);
+       *session_id = uuid;
+
+end:
+       return ret;
+}
+
 /*
  *  lttng_list_sessions
  *

diff --git a/liblttsessiondcomm/liblttsessiondcomm.h b/liblttsessiondcomm/liblttsessiondcomm.h
index 6d6290d0a455cf34e2ec6ed043bdb471864a63f3..56414063c6bacd70b79e50ae697774d61420129a 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;
-       uuid_t session_id;
+       char session_id[37];
        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;
-       uuid_t session_id;
+       char session_id[37];
        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 fb197d43bc60c37228526ba6b72a3b5ff5abc1e2..5a6c5dc97428acceeacbbd78340278097999da21 100644 (file)
--- a/ltt-sessiond/ltt-sessiond.c
+++ b/ltt-sessiond/ltt-sessiond.c
@@ -59,15 +59,16 @@ static int connect_app(pid_t);
 static int init_daemon_socket(void);
 static int process_client_msg(int sock, struct lttcomm_session_msg*);
 static int send_unix_sock(int sock, void *buf, size_t len);
+static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm);
 
 /* Command function */
-static void get_list_apps(void *buf);
-static void get_list_sessions(void *buf);
+static void get_list_apps(pid_t *pids);
+static void get_list_sessions(struct lttng_session *lt);
 
 static void *thread_manage_clients(void *);
 static void *thread_manage_apps(void *);
 
-static int create_session(const char*, uuid_t *);
+static int create_session(char *name, uuid_t *session_id);
 static void destroy_session(uuid_t);
 
 static struct ltt_session *find_session(uuid_t);
@@ -350,9 +351,10 @@ static void destroy_session(uuid_t session_id)
 /*
  *     create_session
  *
- *     Create a brand new session, 
+ *     Create a brand new session and add it to the
+ *     global session list.
  */
-static int create_session(const char *name, uuid_t *session_id)
+static int create_session(char *name, uuid_t *session_id)
 {
        struct ltt_session *new_session;
 
@@ -405,16 +407,15 @@ error:
  *  List traceable user-space application and fill an
  *  array of pids.
  */
-static void get_list_apps(void *buf)
+static void get_list_apps(pid_t *pids)
 {
-       size_t index = 0;
-       struct ltt_traceable_app *iter = NULL;
-       pid_t *pids = (pid_t *) buf;
+       int i = 0;
+       struct ltt_traceable_app *iter;
 
        /* TODO: Mutex needed to access this list */
        cds_list_for_each_entry(iter, &ltt_traceable_app_list.head, list) {
-               pids[index] = iter->pid;
-               index++;
+               pids[i] = iter->pid;
+               i++;
        }
 }
 
@@ -423,20 +424,21 @@ static void get_list_apps(void *buf)
  *
  *  List sessions and fill the data buffer.
  */
-static void get_list_sessions(void *buf)
+static void get_list_sessions(struct lttng_session *lt)
 {
        int i = 0;
-       struct ltt_session *iter = NULL;
+       struct ltt_session *iter;
        struct lttng_session lsess;
-       struct lttng_session *data = (struct lttng_session *) buf;
 
        /* Iterate over session list and append data after
         * the control struct in the buffer.
         */
        cds_list_for_each_entry(iter, &ltt_session_list.head, list) {
+               /* Copy name and uuid */
                uuid_unparse(iter->uuid, lsess.uuid);
                strncpy(lsess.name, iter->name, sizeof(lsess.name));
-               memcpy(data + (i * sizeof(struct lttng_session)), &lsess, sizeof(lsess));
+               lsess.name[sizeof(lsess.name) - 1] = '\0';
+               memcpy(&lt[i], &lsess, sizeof(lsess));
                i++;
                /* Reset struct for next pass */
                memset(&lsess, 0, sizeof(lsess));
@@ -452,10 +454,13 @@ static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_sessi
 {
        llm->cmd_type = lsm->cmd_type;
        llm->pid = lsm->pid;
-       if (!uuid_is_null(lsm->session_id)) {
-               uuid_copy(llm->session_id, lsm->session_id);
+
+       /* Manage uuid */
+       if (lsm->session_id != NULL) {
+               strncpy(llm->session_id, lsm->session_id, UUID_STR_LEN);
        }
-       strncpy(llm->trace_name, lsm->trace_name, sizeof(llm->trace_name));
+
+       strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name));
 }
 
 /*
@@ -466,15 +471,14 @@ static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_sessi
  *
  *  Return total size of the buffer pointed by buf.
  */
-static int setup_data_buffer(void **buf, size_t s_data, struct lttcomm_lttng_msg *llm)
+static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm)
 {
        int ret = 0;
-       void *new_buf;
        size_t buf_size;
 
        buf_size = sizeof(struct lttcomm_lttng_msg) + s_data;
-       new_buf = malloc(buf_size);
-       if (new_buf == NULL) {
+       *buf = malloc(buf_size);
+       if (*buf == NULL) {
                perror("malloc");
                ret = -1;
                goto error;
@@ -484,9 +488,7 @@ static int setup_data_buffer(void **buf, size_t s_data, struct lttcomm_lttng_msg
         * it to the newly allocated buffer.
         */
        llm->size_payload = s_data;
-       memcpy(new_buf, llm, sizeof(struct lttcomm_lttng_msg));
-
-       *buf = new_buf;
+       memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg));
 
        return buf_size;
 
@@ -506,9 +508,9 @@ error:
 static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
 {
        int ret;
-       struct lttcomm_lttng_msg llm;
-       void *send_buf = NULL;
        int buf_size;
+       char *send_buf = NULL;
+       struct lttcomm_lttng_msg llm;
 
        /* Copy common data to identify the response
         * on the lttng client side.
@@ -522,6 +524,29 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
 
        /* Process by command type */
        switch (lsm->cmd_type) {
+               case LTTNG_CREATE_SESSION:
+               {
+                       uuid_t uuid;
+                       ret = create_session(lsm->session_name, &uuid);
+                       if (ret < 0) {
+                               goto error;
+                       }
+
+                       uuid_unparse(uuid, llm.session_id);
+
+                       buf_size = setup_data_buffer(&send_buf, 0, &llm);
+                       if (buf_size < 0) {
+                               ret = LTTCOMM_FATAL;
+                               goto error;
+                       }
+
+                       ret = send_unix_sock(sock, send_buf, buf_size);
+                       if (ret < 0) {
+                               goto send_error;
+                       }
+
+                       break;
+               }
                case UST_LIST_APPS:
                {
                        /* Stop right now if no apps */
@@ -538,7 +563,7 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
                                goto error;
                        }
 
-                       get_list_apps(send_buf + sizeof(struct lttcomm_lttng_msg));
+                       get_list_apps((pid_t *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 
                        ret = send_unix_sock(sock, send_buf, buf_size);
                        if (ret < 0) {
@@ -563,7 +588,7 @@ static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
                                goto error;
                        }
 
-                       get_list_sessions(send_buf + sizeof(struct lttcomm_lttng_msg));
+                       get_list_sessions((struct lttng_session *)(send_buf + sizeof(struct lttcomm_lttng_msg)));
 
                        ret = send_unix_sock(sock, send_buf, buf_size);
                        if (ret < 0) {

diff --git a/lttng/lttng.c b/lttng/lttng.c
index c7ff4edde334dd5131e1b207c902498cc8fc5ce1..b08ecfed8af6debe14aeff7d4f35eb691cc42cd5 100644 (file)
--- a/lttng/lttng.c
+++ b/lttng/lttng.c
@@ -42,6 +42,7 @@ static char *progname;
 static int process_client_opt(void);
 static int process_opt_list_apps(void);
 static int process_opt_list_sessions(void);
+static int process_opt_create_session(void);
 static void sighandler(int sig);
 static int set_signal_handler(void);
 
@@ -76,6 +77,13 @@ static int process_client_opt(void)
                }
        }
 
+       if (opt_create_session != NULL) {
+               ret = process_opt_create_session();
+               if (ret < 0) {
+                       goto end;
+               }
+       }
+
        return 0;
 
 end:
@@ -83,6 +91,29 @@ end:
        return ret;
 }
 
+/*
+ *  process_opt_create_session
+ *
+ *  Create a new session using the name pass
+ *  to the command line.
+ */
+static int process_opt_create_session(void)
+{
+       int ret;
+       char *session_id;
+
+       ret = lttng_create_session(opt_create_session, &session_id);
+       if (ret < 0) {
+               goto error;
+       }
+
+       MSG("Session created:");
+       MSG("    %s (%s)", opt_create_session, session_id);
+
+error:
+       return ret;
+}
+
 /*
  *  process_opt_list_sessions
  *

diff --git a/lttng/lttng.h b/lttng/lttng.h
index be32bf7efa50bd179b181dbc5b1487c7a9d164a7..1faa29d7979298f0cdcc36d7880b0171950b51ac 100644 (file)
--- a/lttng/lttng.h
+++ b/lttng/lttng.h
@@ -28,6 +28,7 @@ extern int opt_verbose;
 extern int opt_quiet;
 extern char *opt_tracing_group;
 extern char *opt_session_name;
+extern char *opt_create_session;
 extern char *opt_sessiond_path;
 extern int opt_list_apps;
 extern int opt_no_sessiond;

diff --git a/lttng/options.c b/lttng/options.c
index 78e1764f9196091f6be3905b5aa3cab4f8d66417..eb31108c446ea5f07f55838245a360ef8861e220 100644 (file)
--- a/lttng/options.c
+++ b/lttng/options.c
@@ -24,6 +24,7 @@
 /* Option variables */
 char *opt_tracing_group;
 char *opt_session_name;
+char *opt_create_session;
 char *opt_sessiond_path;
 int opt_trace_kernel = 0;
 int opt_quiet = 0;
@@ -43,6 +44,7 @@ static struct poptOption long_options[] = {
        {"kernel",                      0,              POPT_ARG_VAL,           &opt_trace_kernel, 1, 0, 0},
        {"no-kernel",           0,              POPT_ARG_VAL,           &opt_trace_kernel, 0, 0, 0},
        {"session",                     0,              POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_session_name, 0, 0},
+       {"create-session",  'c',        POPT_ARG_STRING,        &opt_create_session, 0, 0},
        {"quiet",                       'q',    POPT_ARG_VAL,           &opt_quiet, 1, 0},
        {"verbose",                     'v',    POPT_ARG_VAL,           &opt_verbose, 1, 0},
        {"list-apps",           'l',    POPT_ARG_VAL,           &opt_list_apps, 1, 0},
@@ -62,22 +64,23 @@ static void usage(FILE *ofp)
        fprintf(ofp, "usage : lttng [OPTION]\n");
        fprintf(ofp, "\n");
        fprintf(ofp, "Options:\n");
-       fprintf(ofp, "  -v, --verbose           Verbose mode\n");
-       fprintf(ofp, "  -q, --quiet             Quiet mode\n");
-       fprintf(ofp, "      --help              Show help\n");
-       fprintf(ofp, "      --group NAME        Unix tracing group name. (default: tracing)\n");
-       fprintf(ofp, "      --no-sessiond       Don't spawn a session daemon.\n");
-       fprintf(ofp, "      --sessiond-path     Session daemon full path\n");
+       fprintf(ofp, "  -v, --verbose                Verbose mode\n");
+       fprintf(ofp, "  -q, --quiet                  Quiet mode\n");
+       fprintf(ofp, "      --help                   Show help\n");
+       fprintf(ofp, "      --group NAME             Unix tracing group name. (default: tracing)\n");
+       fprintf(ofp, "      --no-sessiond            Don't spawn a session daemon.\n");
+       fprintf(ofp, "      --sessiond-path          Session daemon full path\n");
        fprintf(ofp, "\n");
        fprintf(ofp, "Session options:\n");
-       fprintf(ofp, "      --list-session      List all available sessions\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, "\n");
        fprintf(ofp, "Tracing options:\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, "      --kernel            Enable kernel tracing\n");
-       //fprintf(ofp, "      --no-kernel         Disable kernel tracing\n");
-       fprintf(ofp, "  -l, --list-apps         List traceable UST applications\n");
+       //fprintf(ofp, "      --kernel               Enable kernel tracing\n");
+       //fprintf(ofp, "      --no-kernel            Disable kernel tracing\n");
+       fprintf(ofp, "  -l, --list-apps              List traceable UST applications\n");
 }
 
 /*