mdw@git.distorted.org.uk Git - mLib/blob - trace/trace.h

   1 /* -*-c-*-
   2  *
   3  * Tracing functions for debugging
   4  *
   5  * (c) 1998 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the mLib utilities library.
  11  *
  12  * mLib is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * mLib is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with mLib; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 #ifndef MLIB_TRACE_H
  29 #define MLIB_TRACE_H
  30
  31 #ifdef __cplusplus
  32   extern "C" {
  33 #endif
  34
  35 /*----- Header files ------------------------------------------------------*/
  36
  37 #include <stdio.h>
  38
  39 #ifndef MLIB_MACROS_H
  40 #  include "macros.h"
  41 #endif
  42
  43 /*----- Data structures ---------------------------------------------------*/
  44
  45 typedef struct trace_opt {
  46   char ch;
  47   unsigned f;
  48   const char *help;
  49 } trace_opt;
  50
  51 /*----- Functions provided ------------------------------------------------*/
  52
  53 /* --- @trace@ --- *
  54  *
  55  * Arguments:   @unsigned l@ = trace level for output
  56  *              @const char *f@ = a @printf@-style format string
  57  *              @...@ = other arguments
  58  *
  59  * Returns:     ---
  60  *
  61  * Use:         Reports a message to the trace output.
  62  */
  63
  64 extern void PRINTF_LIKE(2, 3)
  65   trace(unsigned /*l*/, const char */*f*/, ...);
  66
  67 /* --- @trace_block@ --- *
  68  *
  69  * Arguments:   @unsigned l@ = trace level for output
  70  *              @const char *s@ = some header string to write
  71  *              @const void *b@ = pointer to a block of memory to dump
  72  *              @size_t sz@ = size of the block of memory
  73  *
  74  * Returns:     ---
  75  *
  76  * Use:         Dumps the contents of a block to the trace output.
  77  */
  78
  79 extern void trace_block(unsigned /*l*/, const char */*s*/,
  80                         const void */*b*/, size_t /*sz*/);
  81
  82 /* --- @trace_on@ --- *
  83  *
  84  * Arguments:   @FILE *fp@ = a file to trace on
  85  *              @unsigned l@ = trace level to set
  86  *
  87  * Returns:     ---
  88  *
  89  * Use:         Enables tracing to a file.
  90  */
  91
  92 extern void trace_on(FILE */*fp*/, unsigned /*l*/);
  93
  94 /* --- @trace_custom@ --- *
  95  *
  96  * Arguments:   @void (*func)(const char *buf, size_t sz, void *v)@ =
  97  *                      output function
  98  *              @void *v@ = magic handle to give to function
  99  *
 100  * Returns:     ---
 101  *
 102  * Use:         Sets up a custom trace handler.
 103  */
 104
 105 extern void trace_custom(void (*/*func*/)(const char */*buf*/,
 106                                           size_t /*sz*/, void */*v*/),
 107                          void */*v*/);
 108
 109 /* --- @trace_level@ --- *
 110  *
 111  * Arguments:   @unsigned l@ = trace level to set
 112  *
 113  * Returns:     ---
 114  *
 115  * Use:         Sets the tracing level.
 116  */
 117
 118 extern void trace_level(unsigned /*l*/);
 119
 120 /* --- @tracing@ --- *
 121  *
 122  * Arguments:   ---
 123  *
 124  * Returns:     Zero if not tracing, tracing level if tracing.
 125  *
 126  * Use:         Informs the caller whether tracing is enabled.
 127  */
 128
 129 extern unsigned tracing(void);
 130
 131 /* --- @traceopt@ --- *
 132  *
 133  * Arguments:   @const trace_opt *t@ = pointer to trace options table
 134  *              @const char *p@ = option string supplied by user
 135  *              @unsigned f@ = initial tracing flags
 136  *              @unsigned bad@ = forbidden tracing flags
 137  *
 138  * Returns:     Trace flags as set by user.
 139  *
 140  * Use:         Parses an option string from the user and sets the
 141  *              appropriate trace flags.  If the argument is null or a single
 142  *              `?' character, a help message is displayed.
 143  */
 144
 145 extern unsigned traceopt(const trace_opt */*t*/, const char */*p*/,
 146                          unsigned /*f*/, unsigned /*bad*/);
 147
 148 /*----- Tracing macros ----------------------------------------------------*/
 149
 150 #ifndef NTRACE
 151 #  define T(x) x
 152 #  define IF_TRACING(l, x) if ((l) & tracing()) x
 153 #else
 154 #  define T(x)
 155 #  define IF_TRACING(l, x)
 156 #endif
 157
 158 /*----- That's all, folks -------------------------------------------------*/
 159
 160 #ifdef __cplusplus
 161   }
 162 #endif
 163
 164 #endif