liblttng-ust/lttng-context-ip.c

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * LTTng UST Instruction Pointer Context.
   7  */
   8
   9 #define _LGPL_SOURCE
  10 #include <limits.h>
  11 #include <stddef.h>
  12 #include <sys/types.h>
  13 #include <unistd.h>
  14 #include <lttng/ust-events.h>
  15 #include <lttng/ust-tracer.h>
  16 #include <lttng/ringbuffer-context.h>
  17
  18 #include "context-internal.h"
  19
  20 static
  21 size_t ip_get_size(struct lttng_ust_ctx_field *field, size_t offset)
  22 {
  23         size_t size = 0;
  24
  25         size += lttng_ust_lib_ring_buffer_align(offset, lttng_alignof(void *));
  26         size += sizeof(void *);
  27         return size;
  28 }
  29
  30 static
  31 void ip_record(struct lttng_ust_ctx_field *field,
  32                  struct lttng_ust_lib_ring_buffer_ctx *ctx,
  33                  struct lttng_ust_channel_buffer *chan)
  34 {
  35         void *ip;
  36
  37         ip = ctx->ip;
  38         lttng_ust_lib_ring_buffer_align_ctx(ctx, lttng_alignof(ip));
  39         chan->ops->event_write(ctx, &ip, sizeof(ip));
  40 }
  41
  42 int lttng_add_ip_to_ctx(struct lttng_ust_ctx **ctx)
  43 {
  44         struct lttng_ust_ctx_field *field;
  45         struct lttng_ust_type_common *type;
  46         int ret;
  47
  48         type = lttng_ust_create_type_integer(sizeof(void *) * CHAR_BIT,
  49                         lttng_alignof(void *) * CHAR_BIT,
  50                         lttng_ust_is_signed_type(void *),
  51                         BYTE_ORDER, 16);
  52         if (!type)
  53                 return -ENOMEM;
  54         field = lttng_append_context(ctx);
  55         if (!field) {
  56                 ret = -ENOMEM;
  57                 goto error_context;
  58         }
  59         if (lttng_find_context(*ctx, "ip")) {
  60                 ret = -EEXIST;
  61                 goto error_find_context;
  62         }
  63         field->event_field->name = strdup("ip");
  64         if (!field->event_field->name) {
  65                 ret = -ENOMEM;
  66                 goto error_name;
  67         }
  68         field->event_field->type = type;
  69         field->get_size = ip_get_size;
  70         field->record = ip_record;
  71         lttng_context_update(*ctx);
  72         return 0;
  73
  74 error_name:
  75 error_find_context:
  76         lttng_remove_context_field(ctx, field);
  77 error_context:
  78         lttng_ust_destroy_type(type);
  79         return ret;
  80 }