/*
- * liblttngctl.c
+ * lttng-ctl.c
*
* Linux Trace Toolkit Control Library
*
#include <common/sessiond-comm/sessiond-comm.h>
#include <common/uri.h>
#include <common/utils.h>
+#include <common/dynamic-buffer.h>
#include <lttng/lttng.h>
#include <lttng/health-internal.h>
#include <lttng/trigger/trigger-internal.h>
#include <lttng/endpoint.h>
#include <lttng/channel-internal.h>
+#include <lttng/event-internal.h>
#include "filter/filter-ast.h"
#include "filter/filter-parser.h"
return ret;
}
+/*
+ * Send file descriptors to the session daemon.
+ *
+ * On success, returns the number of bytes sent (>=0)
+ * On error, returns -1
+ */
+static int send_session_fds(const int *fds, size_t nb_fd)
+{
+ int ret;
+
+ if (!connected) {
+ ret = -LTTNG_ERR_NO_SESSIOND;
+ goto end;
+ }
+
+ if (!fds || !nb_fd) {
+ ret = 0;
+ goto end;
+ }
+
+ ret = lttcomm_send_fds_unix_sock(sessiond_socket, fds, nb_fd);
+ if (ret < 0) {
+ ret = -LTTNG_ERR_FATAL;
+ }
+
+end:
+ return ret;
+}
+
/*
* Receive data from the sessiond socket.
*
/*
* Ask the session daemon a specific command and put the data into buf.
- * Takes extra var. len. data as input to send to the session daemon.
+ * Takes extra var. len. data and file descriptors as input to send to the
+ * session daemon.
*
* Return size of data (only payload, not header) or a negative error code.
*/
LTTNG_HIDDEN
-int lttng_ctl_ask_sessiond_varlen(struct lttcomm_session_msg *lsm,
- const void *vardata, size_t vardata_len,
- void **user_payload_buf, void **user_cmd_header_buf,
- size_t *user_cmd_header_len)
+int lttng_ctl_ask_sessiond_fds_varlen(struct lttcomm_session_msg *lsm,
+ const int *fds, size_t nb_fd, const void *vardata,
+ size_t vardata_len, void **user_payload_buf,
+ void **user_cmd_header_buf, size_t *user_cmd_header_len)
{
int ret;
size_t payload_len;
goto end;
}
+ /* Send fds */
+ ret = send_session_fds(fds, nb_fd);
+ if (ret < 0) {
+ /* Ret value is a valid lttng error code. */
+ goto end;
+ }
+
/* Get header from data transmission */
ret = recv_data_sessiond(&llm, sizeof(llm));
if (ret < 0) {
struct lttcomm_event_command_header *cmd_header = NULL;
size_t cmd_header_len;
uint32_t nb_events, i;
- void *extended_at;
+ void *comm_ext_at;
+ void *listing_at;
+ char *reception_buffer = NULL;
+ char *listing = NULL;
+ size_t storage_req;
/* Safety check. An handle and channel name are mandatory */
if (handle == NULL || channel_name == NULL) {
sizeof(lsm.u.list.channel_name));
lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
- ret = lttng_ctl_ask_sessiond_varlen(&lsm, NULL, 0, (void **) events,
- (void **) &cmd_header, &cmd_header_len);
+ ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm, NULL, 0, NULL, 0,
+ (void **) &reception_buffer, (void **) &cmd_header,
+ &cmd_header_len);
if (ret < 0) {
- goto error;
+ goto end;
}
/* Set number of events and free command header */
nb_events = cmd_header->nb_events;
if (nb_events > INT_MAX) {
ret = -EOVERFLOW;
- goto error;
+ goto end;
}
- ret = (int) nb_events;
free(cmd_header);
cmd_header = NULL;
- /* Set extended info pointers */
- extended_at = ((void*) (*events)) +
- nb_events * sizeof(struct lttng_event);
+ /*
+ * The buffer that is returned must contain a "flat" version of
+ * the events that are returned. In other words, all pointers
+ * within an lttng_event must point to a location within the returned
+ * buffer so that the user may free by simply calling free() on the
+ * returned buffer. This is needed in order to maintain API
+ * compatibility.
+ *
+ * A first pass is performed to figure the size of the buffer that
+ * must be returned. A second pass is then performed to setup
+ * the returned events so that their members always point within the
+ * buffer.
+ *
+ * The layout of the returned buffer is as follows:
+ * - struct lttng_event[nb_events],
+ * - nb_events times the following:
+ * - struct lttng_event_extended,
+ * - flattened version of userspace_probe_location
+ * - filter_expression
+ * - exclusions
+ * - padding to align to 64-bits
+ */
+ comm_ext_at = reception_buffer +
+ (nb_events * sizeof(struct lttng_event));
+ storage_req = nb_events * sizeof(struct lttng_event);
for (i = 0; i < nb_events; i++) {
- struct lttcomm_event_extended_header *ext_header;
- struct lttng_event *event = &(*events)[i];
+ struct lttcomm_event_extended_header *ext_comm =
+ (struct lttcomm_event_extended_header *) comm_ext_at;
- event->extended.ptr = extended_at;
- ext_header =
- (struct lttcomm_event_extended_header *) extended_at;
- extended_at += sizeof(*ext_header);
- extended_at += ext_header->filter_len;
- extended_at +=
- ext_header->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
- }
-
- return ret;
-error:
- free(cmd_header);
- free(*events);
- return ret;
-}
-
-int lttng_event_get_filter_expression(struct lttng_event *event,
- const char **filter_expression)
-{
- int ret = 0;
- struct lttcomm_event_extended_header *ext_header;
+ comm_ext_at += sizeof(*ext_comm);
+ comm_ext_at += ext_comm->filter_len;
+ comm_ext_at +=
+ ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
- if (!event || !filter_expression) {
- ret = -LTTNG_ERR_INVALID;
- goto end;
+ storage_req += sizeof(struct lttng_event_extended);
+ /* TODO: missing size of flat userspace probe. */
+ storage_req += ext_comm->filter_len;
+ storage_req += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+ storage_req += storage_req % 8;
}
- ext_header = event->extended.ptr;
-
- if (!ext_header) {
- /*
- * This can happen since the lttng_event structure is
- * used for other tasks where this pointer is never set.
- */
- *filter_expression = NULL;
- goto end;
- }
-
- if (ext_header->filter_len) {
- *filter_expression = ((const char *) (ext_header)) +
- sizeof(*ext_header);
- } else {
- *filter_expression = NULL;
- }
-
-end:
- return ret;
-}
-
-int lttng_event_get_exclusion_name_count(struct lttng_event *event)
-{
- int ret;
- struct lttcomm_event_extended_header *ext_header;
-
- if (!event) {
- ret = -LTTNG_ERR_INVALID;
- goto end;
- }
-
- ext_header = event->extended.ptr;
- if (!ext_header) {
- /*
- * This can happen since the lttng_event structure is
- * used for other tasks where this pointer is never set.
- */
- ret = 0;
+ listing = zmalloc(storage_req);
+ if (!listing) {
goto end;
}
+ memcpy(listing, reception_buffer,
+ nb_events * sizeof(struct lttng_event));
- if (ext_header->nb_exclusions > INT_MAX) {
- ret = -LTTNG_ERR_OVERFLOW;
- goto end;
- }
- ret = (int) ext_header->nb_exclusions;
-end:
- return ret;
-}
-
-int lttng_event_get_exclusion_name(struct lttng_event *event,
- size_t index, const char **exclusion_name)
-{
- int ret = 0;
- struct lttcomm_event_extended_header *ext_header;
- void *at;
-
- if (!event || !exclusion_name) {
- ret = -LTTNG_ERR_INVALID;
- goto end;
- }
-
- ext_header = event->extended.ptr;
- if (!ext_header) {
- ret = -LTTNG_ERR_INVALID;
- goto end;
- }
-
- if (index >= ext_header->nb_exclusions) {
- ret = -LTTNG_ERR_INVALID;
- goto end;
- }
-
- at = (void *) ext_header + sizeof(*ext_header);
- at += ext_header->filter_len;
- at += index * LTTNG_SYMBOL_NAME_LEN;
- *exclusion_name = at;
-
+ comm_ext_at = reception_buffer +
+ (nb_events * sizeof(struct lttng_event));
+ listing_at = listing +
+ (nb_events * sizeof(struct lttng_event));
+ for (i = 0; i < nb_events; i++) {
+ struct lttng_event *event = (struct lttng_event *)
+ (listing + (sizeof(struct lttng_event) * i));
+ struct lttcomm_event_extended_header *ext_comm =
+ (struct lttcomm_event_extended_header *) comm_ext_at;
+ struct lttng_event_extended *event_extended =
+ (struct lttng_event_extended *) listing_at;
+
+ event->extended.ptr = event_extended;
+ listing_at += sizeof(*event_extended);
+ comm_ext_at += sizeof(*ext_comm);
+
+ /* Copy filter expression. */
+ memcpy(listing_at, comm_ext_at, ext_comm->filter_len);
+ event_extended->filter_expression = listing_at;
+ comm_ext_at += ext_comm->filter_len;
+ listing_at += ext_comm->filter_len;
+
+ /* Copy exclusions. */
+ event_extended->exclusions.count = ext_comm->nb_exclusions;
+ event_extended->exclusions.strings = listing_at;
+ memcpy(listing_at, comm_ext_at,
+ ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN);
+ listing_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+ comm_ext_at += ext_comm->nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
+
+ listing_at += ((uintptr_t) listing_at) % 8;
+ }
+
+ *events = (struct lttng_event *) listing;
+ listing = NULL;
+ ret = (int) nb_events;
end:
+ free(cmd_header);
+ free(reception_buffer);
+ free(listing);
return ret;
}
projects / lttng-tools.git / blobdiff