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         ret = fmt->convert_index_timestamp(td);
 141         if (ret < 0)
 142                 goto error;
 143
 144         handle->real_timestamp_begin = fmt->timestamp_begin(td, handle, BT_CLOCK_REAL);
 145         handle->real_timestamp_end = fmt->timestamp_end(td, handle, BT_CLOCK_REAL);
 146         handle->cycles_timestamp_begin = fmt->timestamp_begin(td, handle, BT_CLOCK_CYCLES);
 147         handle->cycles_timestamp_end = fmt->timestamp_end(td, handle, BT_CLOCK_CYCLES);
 148
 149         return handle->id;
 150
 151 error:
 152         closeret = fmt->close_trace(td);
 153         if (closeret) {
 154                 fprintf(stderr, "Error in close_trace callback\n");
 155         }
 156 end:
 157         return ret;
 158 }
 159
 160 int bt_context_remove_trace(struct bt_context *ctx, int handle_id)
 161 {
 162         int ret = 0;
 163
 164         if (!ctx) {
 165                 ret = -EINVAL;
 166                 goto end;
 167         }
 168
 169         /*
 170          * Remove the handle. remove_trace_handle will be called
 171          * automatically.
 172          */
 173         if (!g_hash_table_remove(ctx->trace_handles,
 174                 (gpointer) (unsigned long) handle_id)) {
 175                 ret = -ENOENT;
 176                 goto end;
 177         }
 178 end:
 179         return ret;
 180 }
 181
 182 static
 183 void bt_context_destroy(struct bt_context *ctx)
 184 {
 185         assert(ctx);
 186
 187         /*
 188          * Remove all traces. The g_hash_table_destroy will call
 189          * remove_trace_handle on each element.
 190          */
 191         g_hash_table_destroy(ctx->trace_handles);
 192
 193         bt_finalize_trace_collection(ctx->tc);
 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 }
 214
 215 static
 216 void remove_trace_handle(struct bt_trace_handle *handle)
 217 {
 218         int ret;
 219
 220         /* Remove from containers */
 221         bt_trace_collection_remove(handle->td->ctx->tc, handle->td);
 222         /* Close the trace */
 223         ret = handle->format->close_trace(handle->td);
 224         if (ret) {
 225                 fprintf(stderr, "Error in close_trace callback\n");
 226         }
 227
 228         bt_trace_handle_destroy(handle);
 229 }