formats/ctf/iterator.c

   1 /*
   2  * ctf/iterator.c
   3  *
   4  * Babeltrace Library
   5  *
   6  * Copyright 2011-2012 EfficiOS Inc. and Linux Foundation
   7  *
   8  * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  *         Julien Desfossez <julien.desfossez@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  */
  29
  30 #include <babeltrace/babeltrace.h>
  31 #include <babeltrace/format.h>
  32 #include <babeltrace/ctf/events.h>
  33 #include <babeltrace/ctf-ir/metadata.h>
  34 #include <babeltrace/prio_heap.h>
  35 #include <babeltrace/iterator-internal.h>
  36 #include <babeltrace/ctf/events-internal.h>
  37 #include <babeltrace/ctf/metadata.h>
  38 #include <glib.h>
  39
  40 #include "events-private.h"
  41
  42 struct bt_ctf_iter *bt_ctf_iter_create(struct bt_context *ctx,
  43                 const struct bt_iter_pos *begin_pos,
  44                 const struct bt_iter_pos *end_pos)
  45 {
  46         struct bt_ctf_iter *iter;
  47         int ret;
  48
  49         if (!ctx)
  50                 return NULL;
  51
  52         iter = g_new0(struct bt_ctf_iter, 1);
  53         ret = bt_iter_init(&iter->parent, ctx, begin_pos, end_pos);
  54         if (ret) {
  55                 g_free(iter);
  56                 return NULL;
  57         }
  58         iter->callbacks = g_array_new(FALSE, TRUE,
  59                         sizeof(struct bt_stream_callbacks));
  60         iter->recalculate_dep_graph = 0;
  61         iter->main_callbacks.callback = NULL;
  62         iter->dep_gc = g_ptr_array_new();
  63         return iter;
  64 }
  65
  66 struct bt_ctf_iter *bt_ctf_iter_create_intersect(struct bt_context *ctx,
  67                 struct bt_iter_pos **inter_begin_pos,
  68                 struct bt_iter_pos **inter_end_pos)
  69 {
  70         int ret;
  71         uint64_t begin, end;
  72
  73         /*
  74          * The iterator's range is the union of each trace's intersection of
  75          * streams. This means that we determine the "active" region of each
  76          * trace (that is the region where all of its streams are active), and
  77          * use the TraceCollection to merge all of these active regions.
  78          *
  79          * This results in a union of the traces' active regions.
  80          */
  81         ret = ctf_find_tc_stream_packet_intersection_union(ctx, &begin, &end);
  82         if (ret == 1) {
  83                 fprintf(stderr, "[error] No intersection found between trace files.\n");
  84                 goto error;
  85         } else if (ret != 0) {
  86                 goto error;
  87         }
  88         *inter_begin_pos = bt_iter_create_time_pos(NULL, begin);
  89         if (!(*inter_begin_pos)) {
  90                 goto error;
  91         }
  92         *inter_end_pos = bt_iter_create_time_pos(NULL, end);
  93         if (!(*inter_end_pos)) {
  94                 goto error;
  95         }
  96
  97         ret = ctf_tc_set_stream_intersection_mode(ctx);
  98         if (ret) {
  99                 goto error;
 100         }
 101
 102         /*
 103          * bt_ctf_iter does not take ownership of begin and end positions,
 104          * so we return them to the caller who must still assume their ownership
 105          * until the iterator is destroyed.
 106          */
 107         return bt_ctf_iter_create(ctx, *inter_begin_pos,
 108                         *inter_end_pos);
 109 error:
 110         return NULL;
 111 }
 112
 113 void bt_ctf_iter_destroy(struct bt_ctf_iter *iter)
 114 {
 115         struct bt_stream_callbacks *bt_stream_cb;
 116         struct bt_callback_chain *bt_chain;
 117         int i, j;
 118
 119         assert(iter);
 120
 121         /* free all events callbacks */
 122         if (iter->main_callbacks.callback)
 123                 g_array_free(iter->main_callbacks.callback, TRUE);
 124
 125         /* free per-event callbacks */
 126         for (i = 0; i < iter->callbacks->len; i++) {
 127                 bt_stream_cb = &g_array_index(iter->callbacks,
 128                                 struct bt_stream_callbacks, i);
 129                 if (!bt_stream_cb || !bt_stream_cb->per_id_callbacks)
 130                         continue;
 131                 for (j = 0; j < bt_stream_cb->per_id_callbacks->len; j++) {
 132                         bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
 133                                         struct bt_callback_chain, j);
 134                         if (bt_chain->callback) {
 135                                 g_array_free(bt_chain->callback, TRUE);
 136                         }
 137                 }
 138                 g_array_free(bt_stream_cb->per_id_callbacks, TRUE);
 139         }
 140         g_array_free(iter->callbacks, TRUE);
 141         g_ptr_array_free(iter->dep_gc, TRUE);
 142
 143         bt_iter_fini(&iter->parent);
 144         g_free(iter);
 145 }
 146
 147 struct bt_iter *bt_ctf_get_iter(struct bt_ctf_iter *iter)
 148 {
 149         if (!iter)
 150                 return NULL;
 151
 152         return &iter->parent;
 153 }
 154
 155 struct bt_ctf_event *bt_ctf_iter_read_event_flags(struct bt_ctf_iter *iter,
 156                 int *flags)
 157 {
 158         struct ctf_file_stream *file_stream;
 159         struct bt_ctf_event *ret;
 160         struct ctf_stream_definition *stream;
 161         struct packet_index *packet_index;
 162
 163         /*
 164          * We do not want to fail for any other reason than end of
 165          * trace, hence the assert.
 166          */
 167         assert(iter);
 168
 169         if (flags)
 170                 *flags = 0;
 171
 172         ret = &iter->current_ctf_event;
 173         file_stream = bt_heap_maximum(iter->parent.stream_heap);
 174         if (!file_stream) {
 175                 /* end of file for all streams */
 176                 goto stop;
 177         }
 178
 179         /*
 180          * If the packet is empty (contains only headers or is of size 0), the
 181          * caller has to know that we can't read the current event and we need
 182          * to do a bt_iter_next.
 183          */
 184         if (file_stream->pos.data_offset == file_stream->pos.content_size
 185                         || file_stream->pos.content_size == 0) {
 186                 /* More events may come. */
 187                 ret = NULL;
 188                 if (flags)
 189                         *flags |= BT_ITER_FLAG_RETRY;
 190                 goto end;
 191         }
 192
 193         stream = &file_stream->parent;
 194         if (iter->parent.end_pos &&
 195                 iter->parent.end_pos->type == BT_SEEK_TIME &&
 196                 stream->real_timestamp > iter->parent.end_pos->u.seek_time) {
 197                 goto stop;
 198         }
 199         ret->parent = g_ptr_array_index(stream->events_by_id,
 200                         stream->event_id);
 201
 202         if (!file_stream->pos.packet_index)
 203                 packet_index = NULL;
 204         else
 205                 packet_index = &g_array_index(file_stream->pos.packet_index,
 206                                 struct packet_index, file_stream->pos.cur_index);
 207         iter->events_lost = 0;
 208         if (packet_index && packet_index->events_discarded >
 209                         file_stream->pos.last_events_discarded) {
 210                 if (flags)
 211                         *flags |= BT_ITER_FLAG_LOST_EVENTS;
 212                 iter->events_lost += packet_index->events_discarded -
 213                         file_stream->pos.last_events_discarded;
 214                 file_stream->pos.last_events_discarded =
 215                         packet_index->events_discarded;
 216         }
 217
 218         if (ret->parent->stream->stream_id > iter->callbacks->len)
 219                 goto end;
 220
 221         process_callbacks(iter, ret->parent->stream);
 222
 223 end:
 224         return ret;
 225 stop:
 226         return NULL;
 227 }
 228
 229 struct bt_ctf_event *bt_ctf_iter_read_event(struct bt_ctf_iter *iter)
 230 {
 231         return bt_ctf_iter_read_event_flags(iter, NULL);
 232 }
 233
 234 uint64_t bt_ctf_get_lost_events_count(struct bt_ctf_iter *iter)
 235 {
 236         if (!iter)
 237                 return -1ULL;
 238
 239         return iter->events_lost;
 240 }