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
  22 #include <babeltrace/babeltrace.h>
  23 #include <babeltrace/context.h>
  24 #include <babeltrace/context-internal.h>
  25 #include <babeltrace/trace-handle.h>
  26 #include <babeltrace/trace-handle-internal.h>
  27 #include <babeltrace/trace-collection.h>
  28 #include <babeltrace/format.h>
  29 #include <babeltrace/babeltrace-internal.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <assert.h>
  33 #include <errno.h>
  34
  35 #include <fts.h>
  36 #include <fcntl.h> /* For O_RDONLY */
  37
  38 #include <glib.h>
  39
  40 struct bt_context *bt_context_create(void)
  41 {
  42         struct bt_context *ctx;
  43
  44         ctx = g_new0(struct bt_context, 1);
  45         ctx->refcount = 1;
  46         /* Negative handle id are errors. */
  47         ctx->last_trace_handle_id = 0;
  48
  49         /* Instanciate the trace handle container */
  50         ctx->trace_handles = g_hash_table_new_full(g_direct_hash,
  51                                 g_direct_equal, NULL,
  52                                 (GDestroyNotify) bt_trace_handle_destroy);
  53
  54         ctx->current_iterator = NULL;
  55         ctx->tc = g_new0(struct trace_collection, 1);
  56         init_trace_collection(ctx->tc);
  57
  58         return ctx;
  59 }
  60
  61 int bt_context_add_trace(struct bt_context *ctx, const char *path,
  62                 const char *format_name,
  63                 void (*packet_seek)(struct stream_pos *pos, size_t index,
  64                         int whence),
  65                 struct mmap_stream_list *stream_list,
  66                 FILE *metadata)
  67 {
  68         struct trace_descriptor *td;
  69         struct format *fmt;
  70         struct bt_trace_handle *handle;
  71         int ret;
  72
  73         if (!ctx || !format_name || (!path && !stream_list))
  74                 return -EINVAL;
  75
  76         fmt = bt_lookup_format(g_quark_from_string(format_name));
  77         if (!fmt) {
  78                 fprintf(stderr, "[error] [Context] Format \"%s\" unknown.\n\n",
  79                         format_name);
  80                 ret = -1;
  81                 goto end;
  82         }
  83         if (path) {
  84                 td = fmt->open_trace(path, O_RDONLY, packet_seek, NULL);
  85                 if (!td) {
  86                         fprintf(stderr, "[warning] [Context] Cannot open_trace of the format %s .\n\n",
  87                                         path);
  88                         ret = -1;
  89                         goto end;
  90                 }
  91         } else {
  92                 td = fmt->open_mmap_trace(stream_list, packet_seek, metadata);
  93                 if (!td) {
  94                         fprintf(stderr, "[error] [Context] Cannot open_trace of the format %s .\n\n",
  95                                         path);
  96                         ret = -1;
  97                         goto end;
  98                 }
  99         }
 100
 101         /* Create an handle for the trace */
 102         handle = bt_trace_handle_create(ctx);
 103         if (handle < 0) {
 104                 fprintf(stderr, "[error] [Context] Creating trace handle %s .\n\n",
 105                                 path);
 106                 ret = -1;
 107                 goto end;
 108         }
 109         handle->format = fmt;
 110         handle->td = td;
 111         if (path) {
 112                 strncpy(handle->path, path, PATH_MAX);
 113                 handle->path[PATH_MAX - 1] = '\0';
 114         }
 115
 116         if (fmt->set_handle)
 117                 fmt->set_handle(td, handle);
 118         if (fmt->set_context)
 119                 fmt->set_context(td, ctx);
 120
 121         /* Add new handle to container */
 122         g_hash_table_insert(ctx->trace_handles,
 123                 (gpointer) (unsigned long) handle->id,
 124                 handle);
 125         ret = trace_collection_add(ctx->tc, td);
 126         if (ret != 0)
 127                 goto end;
 128
 129         ret = fmt->convert_index_timestamp(td);
 130         if (ret < 0)
 131                 goto end;
 132
 133         handle->real_timestamp_begin = fmt->timestamp_begin(td, handle, BT_CLOCK_REAL);
 134         handle->real_timestamp_end = fmt->timestamp_end(td, handle, BT_CLOCK_REAL);
 135         handle->cycles_timestamp_begin = fmt->timestamp_begin(td, handle, BT_CLOCK_CYCLES);
 136         handle->cycles_timestamp_end = fmt->timestamp_end(td, handle, BT_CLOCK_CYCLES);
 137
 138         return handle->id;
 139 end:
 140         return ret;
 141 }
 142
 143 int bt_context_remove_trace(struct bt_context *ctx, int handle_id)
 144 {
 145         struct bt_trace_handle *handle;
 146
 147         if (!ctx)
 148                 return -EINVAL;
 149
 150         handle = g_hash_table_lookup(ctx->trace_handles,
 151                 (gpointer) (unsigned long) handle_id);
 152         if (!handle)
 153                 return -ENOENT;
 154
 155         /* Remove from containers */
 156         trace_collection_remove(ctx->tc, handle->td);
 157         /* Close the trace */
 158         handle->format->close_trace(handle->td);
 159
 160         /* Remove and free the handle */
 161         g_hash_table_remove(ctx->trace_handles,
 162                         (gpointer) (unsigned long) handle_id);
 163         return 0;
 164 }
 165
 166 static
 167 void bt_context_destroy(struct bt_context *ctx)
 168 {
 169         assert(ctx);
 170         finalize_trace_collection(ctx->tc);
 171
 172         /* Remote all traces. The g_hash_table_destroy will call
 173          * bt_trace_handle_destroy on each elements.
 174          */
 175         g_hash_table_destroy(ctx->trace_handles);
 176
 177         /* ctx->tc should always be valid */
 178         assert(ctx->tc != NULL);
 179         g_free(ctx->tc);
 180         g_free(ctx);
 181 }
 182
 183 void bt_context_get(struct bt_context *ctx)
 184 {
 185         assert(ctx);
 186         ctx->refcount++;
 187 }
 188
 189 void bt_context_put(struct bt_context *ctx)
 190 {
 191         assert(ctx);
 192         ctx->refcount--;
 193         if (ctx->refcount == 0)
 194                 bt_context_destroy(ctx);
 195 }