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

   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 /*----- Header files ------------------------------------------------------*/
  29
  30 /* --- ANSI headers --- */
  31
  32 #include <ctype.h>
  33 #include <stdarg.h>
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37
  38 /* --- Local headers --- */
  39
  40 #include "dstr.h"
  41 #include "macros.h"
  42 #include "quis.h"
  43 #include "trace.h"
  44
  45 /*----- Private state information -----------------------------------------*/
  46
  47 static void (*tracefunc)(const char *buf, size_t sz, void *v) = 0;
  48 static void *tracearg;
  49 static unsigned tracelvl = 0;           /* How much tracing gets done? */
  50
  51 /*----- Functions provided ------------------------------------------------*/
  52
  53 /* --- @t_file@ --- *
  54  *
  55  * Arguments:   @const char *buf@ = buffer to print
  56  *              @size_t sz@ = buffer size
  57  *              @void *v@ = file handle
  58  *
  59  * Returns:     ---
  60  *
  61  * Use:         Dumps tracing information to a file.
  62  */
  63
  64 static void t_file(const char *buf, size_t sz, void *v)
  65 {
  66   FILE *fp = v;
  67   fprintf(fp, "+ %s: ", QUIS);
  68   fwrite(buf, 1, sz, fp);
  69   fputc('\n', fp);
  70 }
  71
  72 /* --- @trace@ --- *
  73  *
  74  * Arguments:   @unsigned l@ = trace level for output
  75  *              @const char *f@ = a @printf@-style format string
  76  *              @...@ = other arguments
  77  *
  78  * Returns:     ---
  79  *
  80  * Use:         Reports a message to the trace output.
  81  */
  82
  83 void trace(unsigned l, const char *f, ...)
  84 {
  85   va_list ap;
  86   dstr d = DSTR_INIT;
  87   if ((l & tracing()) == 0)
  88     return;
  89   va_start(ap, f);
  90   dstr_vputf(&d, f, &ap);
  91   va_end(ap);
  92   tracefunc(d.buf, d.len, tracearg);
  93   dstr_destroy(&d);
  94 }
  95
  96 /* --- @trace_block@ --- *
  97  *
  98  * Arguments:   @unsigned l@ = trace level for output
  99  *              @const char *s@ = some header string to write
 100  *              @const void *b@ = pointer to a block of memory to dump
 101  *              @size_t sz@ = size of the block of memory
 102  *
 103  * Returns:     ---
 104  *
 105  * Use:         Dumps the contents of a block to the trace output.
 106  */
 107
 108 void trace_block(unsigned l, const char *s, const void *b, size_t sz)
 109 {
 110   const unsigned char *p = b;
 111   size_t i;
 112   unsigned long o = 0;
 113   dstr d = DSTR_INIT;
 114   size_t c;
 115
 116   /* --- Skip if the trace level is too high --- */
 117
 118   if ((l & tracing()) == 0)
 119     return;
 120
 121   /* --- Now start work --- */
 122
 123   tracefunc(s, strlen(s), tracearg);
 124   while (sz) {
 125     dstr_reset(&d);
 126     dstr_putf(&d, "   %08lx : ", o);
 127     for (i = 0; i < 8; i++) {
 128       if (i < sz)
 129         dstr_putf(&d, "%02x ", p[i]);
 130       else
 131         dstr_puts(&d, "** ");
 132     }
 133     dstr_puts(&d, ": ");
 134     for (i = 0; i < 8; i++) {
 135       if (i < sz)
 136         dstr_putc(&d, ISPRINT(p[i]) ? p[i] : '.');
 137       else
 138         dstr_putc(&d, '*');
 139     }
 140     dstr_putz(&d);
 141     tracefunc(d.buf, d.len, tracearg);
 142     c = (sz >= 8) ? 8 : sz;
 143     sz -= c, p += c, o += c;
 144   }
 145   dstr_destroy(&d);
 146 }
 147
 148 /* --- @trace_on@ --- *
 149  *
 150  * Arguments:   @FILE *fp@ = a file to trace on
 151  *              @unsigned l@ = trace level to set
 152  *
 153  * Returns:     ---
 154  *
 155  * Use:         Enables tracing to a file.
 156  */
 157
 158 void trace_on(FILE *fp, unsigned l)
 159 {
 160   tracefunc = t_file;
 161   tracearg = fp;
 162   if (!tracelvl)
 163     tracelvl = l;
 164 }
 165
 166 /* --- @trace_custom@ --- *
 167  *
 168  * Arguments:   @void (*func)(const char *buf, size_t sz, void *v)@ =
 169  *                      output function
 170  *              @void *v@ = magic handle to give to function
 171  *
 172  * Returns:     ---
 173  *
 174  * Use:         Sets up a custom trace handler.
 175  */
 176
 177 void trace_custom(void (*func)(const char */*buf*/,
 178                                size_t /*sz*/, void */*v*/),
 179                   void *v)
 180 {
 181   tracefunc = func;
 182   tracearg = v;
 183 }
 184
 185 /* --- @trace_level@ --- *
 186  *
 187  * Arguments:   @unsigned l@ = trace level to set
 188  *
 189  * Returns:     ---
 190  *
 191  * Use:         Sets the tracing level.
 192  */
 193
 194 void trace_level(unsigned l)
 195 {
 196   tracelvl = l;
 197 }
 198
 199 /* --- @tracing@ --- *
 200  *
 201  * Arguments:   ---
 202  *
 203  * Returns:     Zero if not tracing, tracing level if tracing.
 204  *
 205  * Use:         Informs the caller whether tracing is enabled.
 206  */
 207
 208 unsigned tracing(void)
 209 {
 210   return (tracefunc ? tracelvl : 0u);
 211 }
 212
 213 /*----- That's all, folks -------------------------------------------------*/