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