X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=ltt-sessiond%2Ftrace.c;h=a9ede93eb7b076d5273825606a1d271f10662755;hp=c5d700fd1450b17d842c20a93eef220d75e83d5d;hb=471d16937e160d99382c633db37d89605f483556;hpb=6abb15de23fcd1413963aef20f9f2c243f1bf749 diff --git a/ltt-sessiond/trace.c b/ltt-sessiond/trace.c index c5d700fd1..a9ede93eb 100644 --- a/ltt-sessiond/trace.c +++ b/ltt-sessiond/trace.c @@ -23,18 +23,24 @@ #include #include #include +#include +#include "liblttsessiondcomm.h" #include "lttngerr.h" #include "trace.h" #include "session.h" +static struct ltt_ust_trace *find_session_ust_trace_by_pid( + struct ltt_session *session, pid_t pid); + /* * find_session_ust_trace_by_pid * * Iterate over the session ust_traces and * return a pointer or NULL if not found. */ -struct ltt_ust_trace *find_session_ust_trace_by_pid(struct ltt_session *session, pid_t pid) +static struct ltt_ust_trace *find_session_ust_trace_by_pid( + struct ltt_session *session, pid_t pid) { struct ltt_ust_trace *iter; @@ -97,3 +103,108 @@ void get_traces_per_session(struct ltt_session *session, struct lttng_trace *tra i++; } } + +/* + * ust_create_trace + * + * Create an userspace trace using pid. + * This trace is then appended to the current session + * ust trace list. + */ +int ust_create_trace(int sock, pid_t pid) +{ + int ret; + struct ltt_ust_trace *trace; + + DBG("Creating trace for pid %d", pid); + + trace = malloc(sizeof(struct ltt_ust_trace)); + if (trace == NULL) { + perror("malloc"); + ret = -1; + goto error; + } + + /* Init */ + trace->pid = pid; + trace->shmid = 0; + /* NOTE: to be removed. Trace name will no longer be + * required for LTTng userspace tracer. For now, we set it + * to 'auto' for API compliance. + */ + snprintf(trace->name, 5, "auto"); + + ret = ustctl_create_trace(sock, trace->name); + if (ret < 0) { + ret = LTTCOMM_CREATE_FAIL; + goto error; + } + + /* Check if current session is valid */ + if (current_session) { + cds_list_add(&trace->list, ¤t_session->ust_traces); + current_session->ust_trace_count++; + } + +error: + return ret; +} + +/* + * ust_start_trace + * + * Start a trace. This trace, identified by the pid, must be + * in the current session ust_traces list. + */ +int ust_start_trace(int sock, pid_t pid) +{ + int ret; + struct ltt_ust_trace *trace; + + DBG("Starting trace for pid %d", pid); + + trace = find_session_ust_trace_by_pid(current_session, pid); + if (trace == NULL) { + ret = LTTCOMM_NO_TRACE; + goto error; + } + + ret = ustctl_start_trace(sock, "auto"); + if (ret < 0) { + ret = LTTCOMM_START_FAIL; + goto error; + } + +error: + return ret; +} + +/* + * ust_stop_trace + * + * Stop a trace. This trace, identified by the pid, must be + * in the current session ust_traces list. + */ +int ust_stop_trace(int sock, pid_t pid) +{ + int ret; + struct ltt_ust_trace *trace; + + DBG("Stopping trace for pid %d", pid); + + trace = find_session_ust_trace_by_pid(current_session, pid); + if (trace == NULL) { + ret = LTTCOMM_NO_TRACE; + goto error; + } + + ret = ustctl_stop_trace(sock, trace->name); + if (ret < 0) { + ret = LTTCOMM_STOP_FAIL; + goto error; + } + +error: + return ret; +} +