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/context-internal.h>
  26 #include <babeltrace/ctf-ir/metadata.h>
  27 #include <babeltrace/iterator-internal.h>
  28 #include <inttypes.h>
  29
  30 static
  31 struct bt_dependencies *_babeltrace_dependencies_create(const char *first,
  32                                                         va_list ap)
  33 {
  34         const char *iter;
  35         struct bt_dependencies *dep;
  36
  37         dep = g_new0(struct bt_dependencies, 1);
  38         dep->refcount = 1;
  39         dep->deps = g_array_new(FALSE, TRUE, sizeof(GQuark));
  40         iter = first;
  41         while (iter) {
  42                 GQuark q = g_quark_from_string(iter);
  43                 g_array_append_val(dep->deps, q);
  44                 iter = va_arg(ap, const char *);
  45         }
  46         return dep;
  47 }
  48
  49 struct bt_dependencies *babeltrace_dependencies_create(const char *first, ...)
  50 {
  51         va_list ap;
  52         struct bt_dependencies *deps;
  53
  54         va_start(ap, first);
  55         deps = _babeltrace_dependencies_create(first, ap);
  56         va_end(ap);
  57         return deps;
  58 }
  59
  60 /*
  61  * bt_iter_add_callback: Add a callback to iterator.
  62  */
  63 int bt_iter_add_callback(struct bt_iter *iter,
  64                 bt_event_name event, void *private_data, int flags,
  65                 enum bt_cb_ret (*callback)(struct bt_ctf_data *ctf_data,
  66                                            void *private_data),
  67                 struct bt_dependencies *depends,
  68                 struct bt_dependencies *weak_depends,
  69                 struct bt_dependencies *provides)
  70 {
  71         int i, stream_id;
  72         gpointer *event_id_ptr;
  73         unsigned long event_id;
  74         struct trace_collection *tc = iter->ctx->tc;
  75
  76         for (i = 0; i < tc->array->len; i++) {
  77                 struct ctf_trace *tin;
  78                 struct trace_descriptor *td_read;
  79
  80                 td_read = g_ptr_array_index(tc->array, i);
  81                 tin = container_of(td_read, struct ctf_trace, parent);
  82
  83                 for (stream_id = 0; stream_id < tin->streams->len; stream_id++) {
  84                         struct ctf_stream_class *stream;
  85                         struct bt_stream_callbacks *bt_stream_cb = NULL;
  86                         struct bt_callback_chain *bt_chain = NULL;
  87                         struct bt_callback new_callback;
  88
  89                         stream = g_ptr_array_index(tin->streams, stream_id);
  90
  91                         if (stream_id >= iter->callbacks->len) {
  92                                 g_array_set_size(iter->callbacks, stream->stream_id + 1);
  93                         }
  94                         bt_stream_cb = &g_array_index(iter->callbacks,
  95                                         struct bt_stream_callbacks, stream->stream_id);
  96                         if (!bt_stream_cb->per_id_callbacks) {
  97                                 bt_stream_cb->per_id_callbacks = g_array_new(FALSE, TRUE,
  98                                                 sizeof(struct bt_callback_chain));
  99                         }
 100
 101                         if (event) {
 102                                 /* find the event id */
 103                                 event_id_ptr = g_hash_table_lookup(stream->event_quark_to_id,
 104                                                 (gconstpointer) (unsigned long) event);
 105                                 /* event not found in this stream class */
 106                                 if (!event_id_ptr) {
 107                                         fprintf(stderr, "event not found\n");
 108                                         continue;
 109                                 }
 110                                 event_id = (uint64_t)(unsigned long) *event_id_ptr;
 111
 112                                 /* find or create the bt_callback_chain for this event */
 113                                 if (event_id >= bt_stream_cb->per_id_callbacks->len) {
 114                                         g_array_set_size(bt_stream_cb->per_id_callbacks, event_id + 1);
 115                                 }
 116                                 bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
 117                                                 struct bt_callback_chain, event_id);
 118                                 if (!bt_chain->callback) {
 119                                         bt_chain->callback = g_array_new(FALSE, TRUE,
 120                                                 sizeof(struct bt_callback));
 121                                 }
 122                         } else {
 123                                 /* callback for all events */
 124                                 if (!iter->main_callbacks.callback) {
 125                                         iter->main_callbacks.callback = g_array_new(FALSE, TRUE,
 126                                                         sizeof(struct bt_callback));
 127                                 }
 128                                 bt_chain = &iter->main_callbacks;
 129                         }
 130
 131                         new_callback.private_data = private_data;
 132                         new_callback.flags = flags;
 133                         new_callback.callback = callback;
 134                         new_callback.depends = depends;
 135                         new_callback.weak_depends = weak_depends;
 136                         new_callback.provides = provides;
 137
 138                         /* TODO : take care of priority, for now just FIFO */
 139                         g_array_append_val(bt_chain->callback, new_callback);
 140                 }
 141         }
 142
 143         return 0;
 144 }
 145
 146 static
 147 struct ctf_stream_event *extract_ctf_stream_event(struct ctf_stream *stream)
 148 {
 149         struct ctf_stream_class *stream_class = stream->stream_class;
 150         struct ctf_event *event_class;
 151         struct ctf_stream_event *event;
 152         uint64_t id = stream->event_id;
 153
 154         if (id >= stream_class->events_by_id->len) {
 155                 fprintf(stderr, "[error] Event id %" PRIu64 " is outside range.\n", id);
 156                 return NULL;
 157         }
 158         event = g_ptr_array_index(stream->events_by_id, id);
 159         if (!event) {
 160                 fprintf(stderr, "[error] Event id %" PRIu64 " is unknown.\n", id);
 161                 return NULL;
 162         }
 163         event_class = g_ptr_array_index(stream_class->events_by_id, id);
 164         if (!event_class) {
 165                 fprintf(stderr, "[error] Event id %" PRIu64 " is unknown.\n", id);
 166                 return NULL;
 167         }
 168
 169         return event;
 170 }
 171
 172 void process_callbacks(struct bt_iter *iter,
 173                        struct ctf_stream *stream)
 174 {
 175         struct bt_stream_callbacks *bt_stream_cb;
 176         struct bt_callback_chain *bt_chain;
 177         struct bt_callback *cb;
 178         int i;
 179         enum bt_cb_ret ret;
 180         struct bt_ctf_data ctf_data;
 181
 182         ctf_data.event = extract_ctf_stream_event(stream);
 183         ctf_data.stream = stream;
 184
 185         /* process all events callback first */
 186         if (iter->main_callbacks.callback) {
 187                 for (i = 0; i < iter->main_callbacks.callback->len; i++) {
 188                         cb = &g_array_index(iter->main_callbacks.callback, struct bt_callback, i);
 189                         if (!cb)
 190                                 goto end;
 191                         ret = cb->callback(&ctf_data, cb->private_data);
 192                         switch (ret) {
 193                         case BT_CB_OK_STOP:
 194                         case BT_CB_ERROR_STOP:
 195                                 goto end;
 196                         default:
 197                                 break;
 198                         }
 199                 }
 200         }
 201
 202         /* process per event callbacks */
 203         bt_stream_cb = &g_array_index(iter->callbacks,
 204                         struct bt_stream_callbacks, stream->stream_id);
 205         if (!bt_stream_cb || !bt_stream_cb->per_id_callbacks)
 206                 goto end;
 207
 208         if (stream->event_id > bt_stream_cb->per_id_callbacks->len)
 209                 goto end;
 210         bt_chain = &g_array_index(bt_stream_cb->per_id_callbacks,
 211                         struct bt_callback_chain, stream->event_id);
 212         if (!bt_chain || !bt_chain->callback)
 213                 goto end;
 214
 215         for (i = 0; i < bt_chain->callback->len; i++) {
 216                 cb = &g_array_index(bt_chain->callback, struct bt_callback, i);
 217                 if (!cb)
 218                         goto end;
 219                 ret = cb->callback(&ctf_data, cb->private_data);
 220                 switch (ret) {
 221                 case BT_CB_OK_STOP:
 222                 case BT_CB_ERROR_STOP:
 223                         goto end;
 224                 default:
 225                         break;
 226                 }
 227         }
 228
 229 end:
 230         return;
 231 }