text: /*
   * Copyright (c) 2009, 2010, 2011 Nicira Networks.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at:
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #ifndef COVERAGE_H
  #define COVERAGE_H 1
  
  /* This file implements a simple form of coverage instrumentation.  Points in
   * source code that are of interest must be explicitly annotated with
   * COVERAGE_INC.  The coverage counters may be logged at any time with
   * coverage_log().
   *
   * This form of coverage instrumentation is intended to be so lightweight that
   * it can be enabled in production builds.  It is obviously not a substitute
   * for traditional coverage instrumentation with e.g. "gcov", but it is still
   * a useful debugging tool. */
  
  #include "vlog.h"
  
  /* A coverage counter. */
  struct coverage_counter {
      const char *name;           /* Textual name. */
      unsigned int count;         /* Count within the current epoch. */
      unsigned long long int total; /* Total count over all epochs. */
  };
  
  /* Defines COUNTER.  There must be exactly one such definition at file scope
   * within a program. */
  #if USE_LINKER_SECTIONS
  #define COVERAGE_DEFINE(COUNTER)                                        \
          COVERAGE_DEFINE__(COUNTER);                                     \
          extern struct coverage_counter *counter_ptr_##COUNTER;          \
          struct coverage_counter *counter_ptr_##COUNTER                  \
              __attribute__((section("coverage"))) = &counter_##COUNTER
  #else
  #define COVERAGE_DEFINE(MODULE) \
          extern struct coverage_counter counter_##MODULE
  #endif
  
  /* Adds 1 to COUNTER. */
  #define COVERAGE_INC(COUNTER) counter_##COUNTER.count++;
  
  /* Adds AMOUNT to COUNTER. */
  #define COVERAGE_ADD(COUNTER, AMOUNT) counter_##COUNTER.count += (AMOUNT);
  
  void coverage_init(void);
  void coverage_log(enum vlog_level, bool suppress_dups);
  void coverage_clear(void);
  
  /* Implementation detail. */
  #define COVERAGE_DEFINE__(COUNTER)                              \
          extern struct coverage_counter counter_##COUNTER;       \
          struct coverage_counter counter_##COUNTER = { #COUNTER, 0, 0 }
  
  #endif /* coverage.h */
  