lib/com_err/com_err.c

   1 /*
   2  * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 RCSID("$Id$");
  37 #endif
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <roken.h>
  42 #include "com_err.h"
  43
  44 struct et_list *_et_list = NULL;
  45
  46
  47 const char *
  48 error_message (long code)
  49 {
  50     static char msg[128];
  51     const char *p = com_right(_et_list, code);
  52     if (p == NULL) {
  53         if (code < 0)
  54             snprintf(msg, sizeof(msg), "Unknown error %ld", code);
  55         else
  56             p = strerror(code);
  57     }
  58     if (p != NULL && *p != '\0') {
  59         strlcpy(msg, p, sizeof(msg));
  60     } else
  61         snprintf(msg, sizeof(msg), "Unknown error %ld", code);
  62     return msg;
  63 }
  64
  65 int
  66 init_error_table(const char **msgs, long base, int count)
  67 {
  68     initialize_error_table_r(&_et_list, msgs, count, base);
  69     return 0;
  70 }
  71
  72 static void
  73 default_proc (const char *whoami, long code, const char *fmt, va_list args)
  74     __attribute__((__format__(__printf__, 3, 0)));
  75
  76 static void
  77 default_proc (const char *whoami, long code, const char *fmt, va_list args)
  78 {
  79     if (whoami)
  80       fprintf(stderr, "%s: ", whoami);
  81     if (code)
  82       fprintf(stderr, "%s ", error_message(code));
  83     if (fmt)
  84       vfprintf(stderr, fmt, args);
  85     fprintf(stderr, "\r\n");    /* ??? */
  86 }
  87
  88 static errf com_err_hook = default_proc;
  89
  90 void
  91 com_err_va (const char *whoami,
  92             long code,
  93             const char *fmt,
  94             va_list args)
  95 {
  96     (*com_err_hook) (whoami, code, fmt, args);
  97 }
  98
  99 void
 100 com_err (const char *whoami,
 101          long code,
 102          const char *fmt,
 103          ...)
 104 {
 105     va_list ap;
 106     va_start(ap, fmt);
 107     com_err_va (whoami, code, fmt, ap);
 108     va_end(ap);
 109 }
 110
 111 errf
 112 set_com_err_hook (errf new)
 113 {
 114     errf old = com_err_hook;
 115
 116     if (new)
 117         com_err_hook = new;
 118     else
 119         com_err_hook = default_proc;
 120
 121     return old;
 122 }
 123
 124 errf
 125 reset_com_err_hook (void)
 126 {
 127     return set_com_err_hook(NULL);
 128 }
 129
 130 #define ERRCODE_RANGE   8       /* # of bits to shift table number */
 131 #define BITS_PER_CHAR   6       /* # bits to shift per character in name */
 132
 133 static const char char_set[] =
 134         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_";
 135
 136 static char buf[6];
 137
 138 const char *
 139 error_table_name(int num)
 140 {
 141     int ch;
 142     int i;
 143     char *p;
 144
 145     /* num = aa aaa abb bbb bcc ccc cdd ddd d?? ??? ??? */
 146     p = buf;
 147     num >>= ERRCODE_RANGE;
 148     /* num = ?? ??? ??? aaa aaa bbb bbb ccc ccc ddd ddd */
 149     num &= 077777777;
 150     /* num = 00 000 000 aaa aaa bbb bbb ccc ccc ddd ddd */
 151     for (i = 4; i >= 0; i--) {
 152         ch = (num >> BITS_PER_CHAR * i) & ((1 << BITS_PER_CHAR) - 1);
 153         if (ch != 0)
 154             *p++ = char_set[ch-1];
 155     }
 156     *p = '\0';
 157     return(buf);
 158 }
 159
 160 void
 161 add_to_error_table(struct et_list *new_table)
 162 {
 163     struct et_list *et;
 164
 165     for (et = _et_list; et; et = et->next) {
 166         if (et->table->base == new_table->table->base)
 167             return;
 168     }
 169
 170     new_table->next = _et_list;
 171     _et_list = new_table;
 172 }