lib/coverage.h

   1 /*
   2  * Copyright (c) 2009 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef COVERAGE_H
  18 #define COVERAGE_H 1
  19
  20 /* This file implements a simple form of coverage instrumentation.  Points in
  21  * source code that are of interest must be explicitly annotated with
  22  * COVERAGE_INC.  The coverage counters may be logged at any time with
  23  * coverage_log().
  24  *
  25  * This form of coverage instrumentation is intended to be so lightweight that
  26  * it can be enabled in production builds.  It is obviously not a substitute
  27  * for traditional coverage instrumentation with e.g. "gcov", but it is still
  28  * a useful debugging tool. */
  29
  30 #include "vlog.h"
  31
  32 /* A coverage counter. */
  33 struct coverage_counter {
  34     const char *name;           /* Textual name. */
  35     unsigned int count;         /* Count within the current epoch. */
  36     unsigned long long int total; /* Total count over all epochs. */
  37 };
  38
  39 /* Increments the counter with the given NAME.  Coverage counters need not be
  40  * declared explicitly, but when you add the first coverage counter to a given
  41  * file, you must also add that file to COVERAGE_FILES in lib/automake.mk. */
  42 #define COVERAGE_INC(NAME)                              \
  43     do {                                                \
  44         extern struct coverage_counter NAME##_count;    \
  45         NAME##_count.count++;                           \
  46     } while (0)
  47
  48 /* Adds AMOUNT to the coverage counter with the given NAME. */
  49 #define COVERAGE_ADD(NAME, AMOUNT)                      \
  50     do {                                                \
  51         extern struct coverage_counter NAME##_count;    \
  52         NAME##_count.count += AMOUNT;                   \
  53     } while (0)
  54
  55 void coverage_init(void);
  56 void coverage_log(enum vlog_level, bool suppress_dups);
  57 void coverage_clear(void);
  58
  59 #endif /* coverage.h */