lib/callbacks.c

   1 /*
   2  * callbacks.c
   3  *
   4  * Babeltrace Library
   5  *
   6  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   7  *
   8  * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a copy
  11  * of this software and associated documentation files (the "Software"), to deal
  12  * in the Software without restriction, including without limitation the rights
  13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14  * copies of the Software, and to permit persons to whom the Software is
  15  * furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  */
  20
  21 #include <babeltrace/babeltrace.h>
  22 #include <babeltrace/babeltrace-internal.h>
  23 #include <babeltrace/callbacks-internal.h>
  24 #include <babeltrace/context.h>
  25 #include <babeltrace/ctf-ir/metadata.h>
  26 #include <babeltrace/iterator-internal.h>
  27 #include <inttypes.h>
  28
  29 static
  30 struct bt_dependencies *_babeltrace_dependencies_create(const char *first,
  31                                                         va_list ap)
  32 {
  33         const char *iter;
  34         struct bt_dependencies *dep;
  35
  36         dep = g_new0(struct bt_dependencies, 1);
  37         dep->refcount = 1;
  38         dep->deps = g_array_new(FALSE, TRUE, sizeof(GQuark));
  39         iter = first;
  40         while (iter) {
  41                 GQuark q = g_quark_from_string(iter);
  42                 g_array_append_val(dep->deps, q);
  43                 iter = va_arg(ap, const char *);
  44         }
  45         return dep;
  46 }
  47
  48 struct bt_dependencies *babeltrace_dependencies_create(const char *first, ...)
  49 {
  50         va_list ap;
  51         struct bt_dependencies *deps;
  52
  53         va_start(ap, first);
  54         deps = _babeltrace_dependencies_create(first, ap);
  55         va_end(ap);
  56         return deps;
  57 }
  58
  59 /*
  60  * babeltrace_iter_add_callback: Add a callback to iterator.
  61  */
  62 int babeltrace_iter_add_callback(struct babeltrace_iter *iter,
  63                 bt_event_name event, void *private_data, int flags,
  64                 enum bt_cb_ret (*callback)(struct bt_ctf_data *ctf_data,
  65                                            void *private_data),
  66                 struct bt_dependencies *depends,
  67                 struct bt_dependencies *weak_depends,
  68                 struct bt_dependencies *provides)
  69 {
  70         int i, stream_id;
  71         gpointer *event_id_ptr;
  72         unsigned long event_id;
  73         struct trace_collection *tc = iter->ctx->tc;
  74
  75         for (i = 0; i < tc->array->len; i++) {
  76                 struct ctf_trace *tin;
  77                 struct trace_descriptor *td_read;
  78
  79                 td_read = g_ptr_array_index(tc->array, i);
  80                 tin = container_of(td_read, struct ctf_trace, parent);
  81
  82                 for (stream_id = 0; stream_id < tin->streams->len; stream_id++) {
  83                         struct ctf_stream_class *stream;
  84                         struct bt_stream_callbacks *bt_stream_cb = NULL;
  85                         struct bt_callback_chain *bt_chain = NULL;
  86                         struct bt_callback new_callback;
  87
  88                         stream = g_ptr_array_index(tin->streams, stream_id);
  89
  90                         if (stream_id >= iter->callbacks->len) {
  91                                 g_array_set_size(iter->callbacks, stream->stream_id + 1);
  92                         }
  93                         bt_stream_cb = &g_array_index(iter->callbacks,
  94                                         struct bt_stream_callbacks, stream->stream_id);
  95                         if (!bt_stream_cb->per_id_callbacks) {
  96                                 bt_stream_cb->per_id_callbacks = g_array_new(FALSE, TRUE,
  97                                                 sizeof(struct bt_callback_chain));
  98                         }
  99
 100                         if (event) {
 101                                 /* find the event id */
 102                                 event_id_ptr = g_hash_table_lookup(stream->event_quark_to_id,
 103                                                 (gconstpointer) (unsigned long) event);
 104                                 /* event not found in this stream class */
 105                                 if (!event_id_ptr) {
 106                                         fprintf(stderr, "event not found\n");
 107                                         continue;
 108                                 }
 109                                 event_id = (uint64_t)(unsigned long) *event_id_ptr;
 110
 111                                 /* find or create the bt_callback_chain for this event */
 112                                 if (event_id >= bt_stream_cb->per_id_callbacks->len) {
 113                                         g_array_set_size(bt_stream_cb->per_id_callbacks, event_id + 1);
 114                                 }
 115                                 bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
 116                                                 struct bt_callback_chain, event_id);
 117                                 if (!bt_chain->callback) {
 118                                         bt_chain->callback = g_array_new(FALSE, TRUE,
 119                                                 sizeof(struct bt_callback));
 120                                 }
 121                         } else {
 122                                 /* callback for all events */
 123                                 if (!iter->main_callbacks.callback) {
 124                                         iter->main_callbacks.callback = g_array_new(FALSE, TRUE,
 125                                                         sizeof(struct bt_callback));
 126                                 }
 127                                 bt_chain = &iter->main_callbacks;
 128                         }
 129
 130                         new_callback.private_data = private_data;
 131                         new_callback.flags = flags;
 132                         new_callback.callback = callback;
 133                         new_callback.depends = depends;
 134                         new_callback.weak_depends = weak_depends;
 135                         new_callback.provides = provides;
 136
 137                         /* TODO : take care of priority, for now just FIFO */
 138                         g_array_append_val(bt_chain->callback, new_callback);
 139                 }
 140         }
 141
 142         return 0;
 143 }
 144
 145 static
 146 struct ctf_stream_event *extract_ctf_stream_event(struct ctf_stream *stream)
 147 {
 148         struct ctf_stream_class *stream_class = stream->stream_class;
 149         struct ctf_event *event_class;
 150         struct ctf_stream_event *event;
 151         uint64_t id = stream->event_id;
 152
 153         if (id >= stream_class->events_by_id->len) {
 154                 fprintf(stderr, "[error] Event id %" PRIu64 " is outside range.\n", id);
 155                 return NULL;
 156         }
 157         event = g_ptr_array_index(stream->events_by_id, id);
 158         if (!event) {
 159                 fprintf(stderr, "[error] Event id %" PRIu64 " is unknown.\n", id);
 160                 return NULL;
 161         }
 162         event_class = g_ptr_array_index(stream_class->events_by_id, id);
 163         if (!event_class) {
 164                 fprintf(stderr, "[error] Event id %" PRIu64 " is unknown.\n", id);
 165                 return NULL;
 166         }
 167
 168         return event;
 169 }
 170
 171 void process_callbacks(struct babeltrace_iter *iter,
 172                        struct ctf_stream *stream)
 173 {
 174         struct bt_stream_callbacks *bt_stream_cb;
 175         struct bt_callback_chain *bt_chain;
 176         struct bt_callback *cb;
 177         int i;
 178         enum bt_cb_ret ret;
 179         struct bt_ctf_data ctf_data;
 180
 181         ctf_data.event = extract_ctf_stream_event(stream);
 182         ctf_data.stream = stream;
 183
 184         /* process all events callback first */
 185         if (iter->main_callbacks.callback) {
 186                 for (i = 0; i < iter->main_callbacks.callback->len; i++) {
 187                         cb = &g_array_index(iter->main_callbacks.callback, struct bt_callback, i);
 188                         if (!cb)
 189                                 goto end;
 190                         ret = cb->callback(&ctf_data, cb->private_data);
 191                         switch (ret) {
 192                         case BT_CB_OK_STOP:
 193                         case BT_CB_ERROR_STOP:
 194                                 goto end;
 195                         default:
 196                                 break;
 197                         }
 198                 }
 199         }
 200
 201         /* process per event callbacks */
 202         bt_stream_cb = &g_array_index(iter->callbacks,
 203                         struct bt_stream_callbacks, stream->stream_id);
 204         if (!bt_stream_cb || !bt_stream_cb->per_id_callbacks)
 205                 goto end;
 206
 207         if (stream->event_id > bt_stream_cb->per_id_callbacks->len)
 208                 goto end;
 209         bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
 210                         struct bt_callback_chain, stream->event_id);
 211         if (!bt_chain || !bt_chain->callback)
 212                 goto end;
 213
 214         for (i = 0; i < bt_chain->callback->len; i++) {
 215                 cb = &g_array_index(bt_chain->callback, struct bt_callback, i);
 216                 if (!cb)
 217                         goto end;
 218                 ret = cb->callback(&ctf_data, cb->private_data);
 219                 switch (ret) {
 220                 case BT_CB_OK_STOP:
 221                 case BT_CB_ERROR_STOP:
 222                         goto end;
 223                 default:
 224                         break;
 225                 }
 226         }
 227
 228 end:
 229         return;
 230 }