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_close;
 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         ret = bt_trace_collection_add(ctx->tc, td);
 128         if (ret != 0)
 129                 goto error_destroy_handle;
 130
 131         if (fmt->set_handle)
 132                 fmt->set_handle(td, handle);
 133         if (fmt->set_context)
 134                 fmt->set_context(td, ctx);
 135
 136         if (fmt->convert_index_timestamp) {
 137                 ret = fmt->convert_index_timestamp(td);
 138                 if (ret < 0)
 139                         goto error_collection_del;
 140         }
 141
 142         if (fmt->timestamp_begin)
 143                 handle->real_timestamp_begin = fmt->timestamp_begin(td,
 144                                 handle, BT_CLOCK_REAL);
 145         if (fmt->timestamp_end)
 146                 handle->real_timestamp_end = fmt->timestamp_end(td, handle,
 147                                 BT_CLOCK_REAL);
 148         if (fmt->timestamp_begin)
 149                 handle->cycles_timestamp_begin = fmt->timestamp_begin(td,
 150                                 handle, BT_CLOCK_CYCLES);
 151         if (fmt->timestamp_end)
 152                 handle->cycles_timestamp_end = fmt->timestamp_end(td, handle,
 153                                 BT_CLOCK_CYCLES);
 154
 155         /* Add new handle to container */
 156         g_hash_table_insert(ctx->trace_handles,
 157                 (gpointer) (unsigned long) handle->id,
 158                 handle);
 159
 160         return handle->id;
 161
 162 error_collection_del:
 163         /* Remove from containers */
 164         bt_trace_collection_remove(handle->td->ctx->tc, handle->td);
 165 error_destroy_handle:
 166         bt_trace_handle_destroy(handle);
 167 error_close:
 168         closeret = fmt->close_trace(td);
 169         if (closeret) {
 170                 fprintf(stderr, "Error in close_trace callback\n");
 171         }
 172 end:
 173         return ret;
 174 }
 175
 176 int bt_context_remove_trace(struct bt_context *ctx, int handle_id)
 177 {
 178         int ret = 0;
 179
 180         if (!ctx) {
 181                 ret = -EINVAL;
 182                 goto end;
 183         }
 184
 185         /*
 186          * Remove the handle. remove_trace_handle will be called
 187          * automatically.
 188          */
 189         if (!g_hash_table_remove(ctx->trace_handles,
 190                 (gpointer) (unsigned long) handle_id)) {
 191                 ret = -ENOENT;
 192                 goto end;
 193         }
 194 end:
 195         return ret;
 196 }
 197
 198 static
 199 void bt_context_destroy(struct bt_context *ctx)
 200 {
 201         assert(ctx);
 202
 203         /*
 204          * Remove all traces. The g_hash_table_destroy will call
 205          * remove_trace_handle on each element.
 206          */
 207         g_hash_table_destroy(ctx->trace_handles);
 208
 209         bt_finalize_trace_collection(ctx->tc);
 210
 211         /* ctx->tc should always be valid */
 212         assert(ctx->tc != NULL);
 213         g_free(ctx->tc);
 214         g_free(ctx);
 215 }
 216
 217 void bt_context_get(struct bt_context *ctx)
 218 {
 219         assert(ctx);
 220         ctx->refcount++;
 221 }
 222
 223 void bt_context_put(struct bt_context *ctx)
 224 {
 225         assert(ctx);
 226         ctx->refcount--;
 227         if (ctx->refcount == 0)
 228                 bt_context_destroy(ctx);
 229 }
 230
 231 static
 232 void remove_trace_handle(struct bt_trace_handle *handle)
 233 {
 234         int ret;
 235
 236         if (!handle->td->ctx)
 237                 return;
 238         /* Remove from containers */
 239         bt_trace_collection_remove(handle->td->ctx->tc, handle->td);
 240         /* Close the trace */
 241         ret = handle->format->close_trace(handle->td);
 242         if (ret) {
 243                 fprintf(stderr, "Error in close_trace callback\n");
 244         }
 245
 246         bt_trace_handle_destroy(handle);
 247 }