rom/dos/fault.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: dos.library function Fault()
   6     Lang: english
   7 */
   8 #include <aros/options.h>
   9 #include "dos_intern.h"
  10 #if PassThroughErrnos
  11 #   include <errno.h>
  12 #endif
  13 #include <string.h>
  14
  15 /*****************************************************************************
  16
  17     NAME */
  18 #include <proto/dos.h>
  19
  20         AROS_LH4(BOOL, Fault,
  21
  22 /*  SYNOPSIS */
  23         AROS_LHA(LONG,         code,   D1),
  24         AROS_LHA(CONST_STRPTR, header, D2),
  25         AROS_LHA(STRPTR,       buffer, D3),
  26         AROS_LHA(LONG,         len,    D4),
  27
  28 /*  LOCATION */
  29         struct DosLibrary *, DOSBase, 78, Dos)
  30
  31 /*  FUNCTION
  32         Fault will obtain the error message string for the given error
  33         code. First the header string is copied to the buffer, followed
  34         by a ":" (colon), then the NULL terminated string for the error
  35         message into the buffer.
  36
  37         By convention, error messages are ALWAYS less than 80 (plus 1 for
  38         NULL termination), and ideally less than 60 characters.
  39
  40         If the error code is not know, then the string "Unknown error"
  41         followed by the error number will be added to the string.
  42
  43     INPUTS
  44         code    -   The error code.
  45         header  -   The string to prepend to the buffer before the error
  46                     text. This may be NULL in which case nothing is prepended.
  47         buffer  -   The destination buffer.
  48         len     -   Length of the buffer.
  49
  50     RESULT
  51         Number of characters placed in the buffer, may be 0.
  52
  53     NOTES
  54
  55     EXAMPLE
  56
  57     BUGS
  58
  59     SEE ALSO
  60
  61     INTERNALS
  62
  63 *****************************************************************************/
  64 {
  65     AROS_LIBFUNC_INIT
  66     AROS_LIBBASE_EXT_DECL(struct DosLibrary *,DOSBase)
  67
  68     LONG index = 0;
  69     STRPTR theString;
  70
  71     if (code == 0)
  72     {
  73         *buffer = '\0';
  74         return 0;
  75     }
  76
  77     /* Do this to make sure there is room for a NULL terminator */
  78     len--;
  79
  80     if (header)
  81     {
  82         while((index < len) && *header)
  83         {
  84             buffer[index++] = *header++;
  85         }
  86
  87         buffer[index++] = ':';
  88         buffer[index++] = ' ';
  89     }
  90
  91     theString = DosGetString(code);
  92 #if PassThroughErrnos
  93     if ((!theString) && (code & PassThroughErrnos))
  94     {
  95         theString = strerror (code ^ PassThroughErrnos);
  96     }
  97 #endif
  98     if(theString)
  99     {
 100         while((index < len) && *theString)
 101         {
 102             buffer[index++] = *theString++;
 103         }
 104     }
 105     else
 106     {
 107         /* String buffer/index for long 2 string */
 108         UBYTE l2str[12], l2idx = 11;
 109
 110         theString = "Unknown error ";
 111         while((index < len) && *theString)
 112         {
 113             buffer[index++] = *theString++;
 114         }
 115
 116         /* If the number is negative, whack in a - sign. */
 117         if(code < 0)
 118         {
 119             code = -code;
 120             buffer[index++] = '-';
 121         }
 122
 123         /* Convert the number to a string, I work backwards, its easier */
 124         l2str[l2idx--] = '\0';
 125         while(code != 0)
 126         {
 127             l2str[l2idx--] = (code % 10) + '0';
 128             code /= 10;
 129         }
 130
 131         l2str[l2idx] = ' ';
 132
 133         /* Copy the number onto the fault string */
 134         while((index < len) && l2str[l2idx])
 135         {
 136             buffer[index++] = l2str[l2idx++];
 137         }
 138     }
 139     buffer[index] = '\0';
 140     return (len - index + 1);
 141
 142     AROS_LIBFUNC_EXIT
 143 } /* Fault */