+++ /dev/null
-/*
- * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; only version 2
- * of the License.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-
-#ifndef _LIBLTTKCONSUMERD_H
-#define _LIBLTTKCONSUMERD_H
-
-#include <lttng-sessiond-comm.h>
-#include "lttng-kconsumerd.h"
-
-/*
- * When the receiving thread dies, we need to have a way to make
- * the polling thread exit eventually.
- * If all FDs hang up (normal case when the ltt-sessiond stops),
- * we can exit cleanly, but if there is a problem and for whatever
- * reason some FDs remain open, the consumer should still exit eventually.
- *
- * If the timeout is reached, it means that during this period
- * no events occurred on the FDs so we need to force an exit.
- * This case should not happen but it is a safety to ensure we won't block
- * the consumer indefinitely.
- *
- * The value of 2 seconds is an arbitrary choice.
- */
-#define KCONSUMERD_POLL_GRACE_PERIOD 2000
-
-struct kconsumerd_fd_list {
- struct cds_list_head head;
-};
-
-/*
- * Internal representation of the FDs,
- * sessiond_fd is used to identify uniquely a fd
- */
-struct kconsumerd_fd {
- struct cds_list_head list;
- int sessiond_fd; /* used to identify uniquely a fd with sessiond */
- int consumerd_fd; /* fd to consume */
- int out_fd; /* output file to write the data */
- off_t out_fd_offset; /* write position in the output file descriptor */
- char path_name[PATH_MAX]; /* tracefile name */
- enum kconsumerd_fd_state state;
- unsigned long max_sb_size; /* the subbuffer size for this channel */
- void *mmap_base;
- size_t mmap_len;
- enum lttng_event_output output; /* splice or mmap */
-};
-
-struct kconsumerd_local_data {
- /* function to call when data is available on a buffer */
- int (*on_buffer_ready)(struct kconsumerd_fd *kconsumerd_fd);
- /* socket to communicate errors with sessiond */
- int kconsumerd_error_socket;
- /* socket to exchange commands with sessiond */
- char *kconsumerd_command_sock_path;
- /* communication with splice */
- int kconsumerd_thread_pipe[2];
- /* pipe to wake the poll thread when necessary */
- int kconsumerd_poll_pipe[2];
- /* to let the signal handler wake up the fd receiver thread */
- int kconsumerd_should_quit[2];
-};
-
-/*
- * kconsumerd_create
- * initialise the necessary environnement :
- * - create a new context
- * - create the poll_pipe
- * - create the should_quit pipe (for signal handler)
- * - create the thread pipe (for splice)
- * Takes a function pointer as argument, this function is called when data is
- * available on a buffer. This function is responsible to do the
- * kernctl_get_next_subbuf, read the data with mmap or splice depending on the
- * buffer configuration and then kernctl_put_next_subbuf at the end.
- * Returns a pointer to the new context or NULL on error.
- */
-struct kconsumerd_local_data *kconsumerd_create(
- int (*buffer_ready)(struct kconsumerd_fd *kconsumerd_fd));
-
-/*
- * kconsumerd_destroy
- * Close all fds associated with the instance and free the context
- */
-void kconsumerd_destroy(struct kconsumerd_local_data *ctx);
-
-/*
- * kconsumerd_on_read_subbuffer_mmap
- * mmap the ring buffer, read it and write the data to the tracefile.
- * Returns the number of bytes written
- */
-int kconsumerd_on_read_subbuffer_mmap(struct kconsumerd_local_data *ctx,
- struct kconsumerd_fd *kconsumerd_fd, unsigned long len);
-
-/*
- * kconsumerd_on_read_subbuffer
- *
- * Splice the data from the ring buffer to the tracefile.
- * Returns the number of bytes spliced
- */
-int kconsumerd_on_read_subbuffer_splice(struct kconsumerd_local_data *ctx,
- struct kconsumerd_fd *kconsumerd_fd, unsigned long len);
-
-/*
- * kconsumerd_send_error
- * send return code to ltt-sessiond
- * returns the return code of sendmsg : the number of bytes transmitted
- * or -1 on error.
- */
-int kconsumerd_send_error(struct kconsumerd_local_data *ctx,
- enum lttcomm_return_code cmd);
-
-/*
- * kconsumerd_poll_socket
- * Poll on the should_quit pipe and the command socket
- * return -1 on error and should exit, 0 if data is
- * available on the command socket
- */
-int kconsumerd_poll_socket(struct pollfd *kconsumerd_sockpoll);
-
-/*
- * kconsumerd_thread_poll_fds
- * This thread polls the fds in the ltt_fd_list to consume the data
- * and write it to tracefile if necessary.
- */
-void *kconsumerd_thread_poll_fds(void *data);
-
-/*
- * kconsumerd_thread_receive_fds
- * This thread listens on the consumerd socket and
- * receives the file descriptors from ltt-sessiond
- */
-void *kconsumerd_thread_receive_fds(void *data);
-
-/*
- * kconsumerd_should_exit
- * Called from signal handler to ensure a clean exit
- */
-void kconsumerd_should_exit(struct kconsumerd_local_data *ctx);
-
-/*
- * kconsumerd_cleanup
- * Cleanup the daemon's socket on exit
- */
-void kconsumerd_cleanup(void);
-
-/*
- * kconsumerd_set_error_socket
- * Set the error socket for communication with a session daemon
- */
-void kconsumerd_set_error_socket(struct kconsumerd_local_data *ctx, int sock);
-
-/*
- * kconsumerd_set_command_socket_path
- * Set the command socket path for communication with a session daemon
- */
-void kconsumerd_set_command_socket_path(struct kconsumerd_local_data *ctx, char *sock);
-
-#endif /* _LIBLTTKCONSUMERD_H */
projects / lttng-tools.git / blobdiff