lib/context.c

   1 /*
   2  * context.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/context.h>
  32 #include <babeltrace/context-internal.h>
  33 #include <babeltrace/trace-handle.h>
  34 #include <babeltrace/trace-handle-internal.h>
  35 #include <babeltrace/trace-collection.h>
  36 #include <babeltrace/format.h>
  37 #include <babeltrace/format-internal.h>
  38 #include <babeltrace/babeltrace-internal.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <assert.h>
  42 #include <errno.h>
  43
  44 #include <fcntl.h> /* For O_RDONLY */
  45
  46 #include <glib.h>
  47
  48 static
  49 void remove_trace_handle(struct bt_trace_handle *handle);
  50
  51 struct bt_context *bt_context_create(void)
  52 {
  53         struct bt_context *ctx;
  54
  55         ctx = g_new0(struct bt_context, 1);
  56         ctx->refcount = 1;
  57         /* Negative handle id are errors. */
  58         ctx->last_trace_handle_id = 0;
  59
  60         /* Instanciate the trace handle container */
  61         ctx->trace_handles = g_hash_table_new_full(g_direct_hash,
  62                                 g_direct_equal, NULL,
  63                                 (GDestroyNotify) remove_trace_handle);
  64
  65         ctx->current_iterator = NULL;
  66         ctx->tc = g_new0(struct trace_collection, 1);
  67         bt_init_trace_collection(ctx->tc);
  68
  69         return ctx;
  70 }
  71
  72 int bt_context_add_trace(struct bt_context *ctx, const char *path,
  73                 const char *format_name,
  74                 void (*packet_seek)(struct bt_stream_pos *pos, size_t index,
  75                         int whence),
  76                 struct bt_mmap_stream_list *stream_list,
  77                 FILE *metadata)
  78 {
  79         struct bt_trace_descriptor *td;
  80         struct bt_format *fmt;
  81         struct bt_trace_handle *handle;
  82         int ret, closeret;
  83
  84         if (!ctx || !format_name || (!path && !stream_list))
  85                 return -EINVAL;
  86
  87         fmt = bt_lookup_format(g_quark_from_string(format_name));
  88         if (!fmt) {
  89                 fprintf(stderr, "[error] [Context] Format \"%s\" unknown.\n\n",
  90                         format_name);
  91                 ret = -1;
  92                 goto end;
  93         }
  94         if (path) {
  95                 td = fmt->open_trace(path, O_RDONLY, packet_seek, NULL);
  96                 if (!td) {
  97                         fprintf(stderr, "[warning] [Context] Cannot open_trace of format %s at path %s.\n",
  98                                         format_name, path);
  99                         ret = -1;
 100                         goto end;
 101                 }
 102         } else {
 103                 td = fmt->open_mmap_trace(stream_list, packet_seek, metadata);
 104                 if (!td) {
 105                         fprintf(stderr, "[error] [Context] Cannot open_mmap_trace of format %s.\n\n",
 106                                         format_name);
 107                         ret = -1;
 108                         goto end;
 109                 }
 110         }
 111
 112         /* Create an handle for the trace */
 113         handle = bt_trace_handle_create(ctx);
 114         if (!handle) {
 115                 fprintf(stderr, "[error] [Context] Creating trace handle %s .\n\n",
 116                                 path);
 117                 ret = -1;
 118                 goto error;
 119         }
 120         handle->format = fmt;
 121         handle->td = td;
 122         if (path) {
 123                 strncpy(handle->path, path, PATH_MAX);
 124                 handle->path[PATH_MAX - 1] = '\0';
 125         }
 126
 127         if (fmt->set_handle)
 128                 fmt->set_handle(td, handle);
 129         if (fmt->set_context)
 130                 fmt->set_context(td, ctx);
 131
 132         /* Add new handle to container */
 133         g_hash_table_insert(ctx->trace_handles,
 134                 (gpointer) (unsigned long) handle->id,
 135                 handle);
 136         ret = bt_trace_collection_add(ctx->tc, td);
 137         if (ret != 0)
 138                 goto error;
 139
 140         if (fmt->convert_index_timestamp) {
 141                 ret = fmt->convert_index_timestamp(td);
 142                 if (ret < 0)
 143                         goto error;
 144         }
 145
 146         if (fmt->timestamp_begin)
 147                 handle->real_timestamp_begin = fmt->timestamp_begin(td,
 148                                 handle, BT_CLOCK_REAL);
 149         if (fmt->timestamp_end)
 150                 handle->real_timestamp_end = fmt->timestamp_end(td, handle,
 151                                 BT_CLOCK_REAL);
 152         if (fmt->timestamp_begin)
 153                 handle->cycles_timestamp_begin = fmt->timestamp_begin(td,
 154                                 handle, BT_CLOCK_CYCLES);
 155         if (fmt->timestamp_end)
 156                 handle->cycles_timestamp_end = fmt->timestamp_end(td, handle,
 157                                 BT_CLOCK_CYCLES);
 158
 159         return handle->id;
 160
 161 error:
 162         closeret = fmt->close_trace(td);
 163         if (closeret) {
 164                 fprintf(stderr, "Error in close_trace callback\n");
 165         }
 166 end:
 167         return ret;
 168 }
 169
 170 int bt_context_remove_trace(struct bt_context *ctx, int handle_id)
 171 {
 172         int ret = 0;
 173
 174         if (!ctx) {
 175                 ret = -EINVAL;
 176                 goto end;
 177         }
 178
 179         /*
 180          * Remove the handle. remove_trace_handle will be called
 181          * automatically.
 182          */
 183         if (!g_hash_table_remove(ctx->trace_handles,
 184                 (gpointer) (unsigned long) handle_id)) {
 185                 ret = -ENOENT;
 186                 goto end;
 187         }
 188 end:
 189         return ret;
 190 }
 191
 192 static
 193 void bt_context_destroy(struct bt_context *ctx)
 194 {
 195         assert(ctx);
 196
 197         /*
 198          * Remove all traces. The g_hash_table_destroy will call
 199          * remove_trace_handle on each element.
 200          */
 201         g_hash_table_destroy(ctx->trace_handles);
 202
 203         bt_finalize_trace_collection(ctx->tc);
 204
 205         /* ctx->tc should always be valid */
 206         assert(ctx->tc != NULL);
 207         g_free(ctx->tc);
 208         g_free(ctx);
 209 }
 210
 211 void bt_context_get(struct bt_context *ctx)
 212 {
 213         assert(ctx);
 214         ctx->refcount++;
 215 }
 216
 217 void bt_context_put(struct bt_context *ctx)
 218 {
 219         assert(ctx);
 220         ctx->refcount--;
 221         if (ctx->refcount == 0)
 222                 bt_context_destroy(ctx);
 223 }
 224
 225 static
 226 void remove_trace_handle(struct bt_trace_handle *handle)
 227 {
 228         int ret;
 229
 230         if (!handle->td->ctx)
 231                 return;
 232         /* Remove from containers */
 233         bt_trace_collection_remove(handle->td->ctx->tc, handle->td);
 234         /* Close the trace */
 235         ret = handle->format->close_trace(handle->td);
 236         if (ret) {
 237                 fprintf(stderr, "Error in close_trace callback\n");
 238         }
 239
 240         bt_trace_handle_destroy(handle);
 241 }