ltt-sessiond/trace.c

   1 /*
   2  * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <urcu/list.h>
  24
  25 #include "ltt-sessiond.h"
  26 #include "trace.h"
  27
  28 /*
  29  *  trace_create_kernel_session
  30  *
  31  *  Allocate and initialize a kernel session data structure.
  32  *
  33  *  Return pointer to structure or NULL.
  34  */
  35 struct ltt_kernel_session *trace_create_kernel_session(void)
  36 {
  37         struct ltt_kernel_session *lks;
  38
  39         /* Allocate a new ltt kernel session */
  40         lks = malloc(sizeof(struct ltt_kernel_session));
  41         if (lks == NULL) {
  42                 perror("create kernel session malloc");
  43                 goto error;
  44         }
  45
  46         /* Init data structure */
  47         lks->fd = 0;
  48         lks->metadata_stream_fd = 0;
  49         lks->channel_count = 0;
  50         lks->stream_count_global = 0;
  51         lks->metadata = NULL;
  52         CDS_INIT_LIST_HEAD(&lks->channel_list.head);
  53
  54         return lks;
  55
  56 error:
  57         return NULL;
  58 }
  59
  60 /*
  61  *  trace_create_kernel_channel
  62  *
  63  *  Allocate and initialize a kernel channel data structure.
  64  *
  65  *  Return pointer to structure or NULL.
  66  */
  67 struct ltt_kernel_channel *trace_create_kernel_channel(void)
  68 {
  69         int ret;
  70         struct ltt_kernel_channel *lkc;
  71         struct lttng_kernel_channel *chan;
  72
  73         lkc = malloc(sizeof(struct ltt_kernel_channel));
  74         chan = malloc(sizeof(struct lttng_kernel_channel));
  75         if (lkc == NULL || chan == NULL) {
  76                 perror("kernel channel malloc");
  77                 goto error;
  78         }
  79
  80         /* Default value to channel */
  81         chan->overwrite = DEFAULT_KERNEL_OVERWRITE;
  82         chan->subbuf_size = DEFAULT_KERNEL_SUBBUF_SIZE;
  83         chan->num_subbuf = DEFAULT_KERNEL_SUBBUF_NUM;
  84         chan->switch_timer_interval = DEFAULT_KERNEL_SWITCH_TIMER;
  85         chan->read_timer_interval = DEFAULT_KERNEL_READ_TIMER;
  86
  87         lkc->fd = 0;
  88         lkc->stream_count = 0;
  89         lkc->channel = chan;
  90         /* Init linked list */
  91         CDS_INIT_LIST_HEAD(&lkc->events_list.head);
  92         CDS_INIT_LIST_HEAD(&lkc->stream_list.head);
  93         /* Set default trace output path */
  94         ret = asprintf(&lkc->pathname, "%s", DEFAULT_TRACE_OUTPUT);
  95         if (ret < 0) {
  96                 perror("asprintf kernel create channel");
  97                 goto error;
  98         }
  99
 100         return lkc;
 101
 102 error:
 103         return NULL;
 104 }
 105
 106 /*
 107  *  trace_create_kernel_event
 108  *
 109  *  Allocate and initialize a kernel event. Set name and event type.
 110  *
 111  *  Return pointer to structure or NULL.
 112  */
 113 struct ltt_kernel_event *trace_create_kernel_event(char *name,
 114                 enum lttng_kernel_instrumentation type)
 115 {
 116         struct ltt_kernel_event *lke;
 117         struct lttng_kernel_event *attr;
 118
 119         lke = malloc(sizeof(struct ltt_kernel_event));
 120         attr = malloc(sizeof(struct lttng_kernel_event));
 121         if (lke == NULL || attr == NULL) {
 122                 perror("kernel event malloc");
 123                 goto error;
 124         }
 125
 126         /* Init event attribute */
 127         attr->instrumentation = type;
 128         strncpy(attr->name, name, LTTNG_SYM_NAME_LEN);
 129         /* Setting up a kernel event */
 130         lke->fd = 0;
 131         lke->event = attr;
 132
 133         return lke;
 134
 135 error:
 136         return NULL;
 137 }
 138
 139 /*
 140  *  trace_create_kernel_metadata
 141  *
 142  *  Allocate and initialize a kernel metadata.
 143  *
 144  *  Return pointer to structure or NULL.
 145  */
 146 struct ltt_kernel_metadata *trace_create_kernel_metadata(void)
 147 {
 148         int ret;
 149         struct ltt_kernel_metadata *lkm;
 150         struct lttng_kernel_channel *attr;
 151
 152         lkm = malloc(sizeof(struct ltt_kernel_metadata));
 153         attr = malloc(sizeof(struct lttng_kernel_channel));
 154         if (lkm == NULL || attr == NULL) {
 155                 perror("kernel metadata malloc");
 156                 goto error;
 157         }
 158
 159         /* Set default attributes */
 160         attr->overwrite = DEFAULT_KERNEL_OVERWRITE;
 161         attr->subbuf_size = DEFAULT_KERNEL_SUBBUF_SIZE;
 162         attr->num_subbuf = DEFAULT_KERNEL_SUBBUF_NUM;
 163         attr->switch_timer_interval = DEFAULT_KERNEL_SWITCH_TIMER;
 164         attr->read_timer_interval = DEFAULT_KERNEL_READ_TIMER;
 165
 166         /* Init metadata */
 167         lkm->fd = 0;
 168         lkm->conf = attr;
 169         /* Set default metadata path */
 170         ret = asprintf(&lkm->pathname, "%s/metadata", DEFAULT_TRACE_OUTPUT);
 171         if (ret < 0) {
 172                 perror("asprintf kernel metadata");
 173                 goto error;
 174         }
 175
 176         return lkm;
 177
 178 error:
 179         return NULL;
 180 }
 181
 182 /*
 183  *  trace_create_kernel_stream
 184  *
 185  *  Allocate and initialize a kernel stream. The stream is set to ACTIVE_FD by
 186  *  default.
 187  *
 188  *  Return pointer to structure or NULL.
 189  */
 190 struct ltt_kernel_stream *trace_create_kernel_stream(void)
 191 {
 192         struct ltt_kernel_stream *lks;
 193
 194         lks = malloc(sizeof(struct ltt_kernel_stream));
 195         if (lks == NULL) {
 196                 perror("kernel stream malloc");
 197                 goto error;
 198         }
 199
 200         /* Init stream */
 201         lks->fd = 0;
 202         lks->pathname = NULL;
 203         lks->state = 0;
 204
 205         return lks;
 206
 207 error:
 208         return NULL;
 209 }