/*
* Copyright (c) 2000, 2001, 2002, 2003, 2004, 2012 by Martin C. Shepherd.
*
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, and/or sell copies of the Software, and to permit persons
* to whom the Software is furnished to do so, provided that the above
* copyright notice(s) and this permission notice appear in all copies of
* the Software and that both the above copyright notice(s) and this
* permission notice appear in supporting documentation.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
* OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
* HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
* INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
* FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Except as contained in this notice, the name of a copyright holder
* shall not be used in advertising or otherwise to promote the sale, use
* or other dealings in this Software without prior written authorization
* of the copyright holder.
*/
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include "errmsg.h"
/*
* Encapsulate the error reporting buffer in an opaque object.
*/
struct ErrMsg {
char msg[ERR_MSG_LEN+1]; /* An error message */
};
/*.......................................................................
* Create a new error-message object.
*
* Output:
* return ErrMsg * The new object, or NULL on error.
*/
ErrMsg *_new_ErrMsg(void)
{
ErrMsg *err; /* The object to be returned */
/*
* Allocate the container.
*/
err = malloc(sizeof(ErrMsg));
if(!err) {
errno = ENOMEM;
return NULL;
};
/*
* Before attempting any operation that might fail, initialize the
* container at least up to the point at which it can safely be passed
* to del_ErrMsg().
*/
err->msg[0] = '\0';
return err;
}
/*.......................................................................
* Delete an error-message object.
*
* Input:
* err ErrMsg * The object to be deleted.
* Output:
* return ErrMsg * The deleted object (always NULL).
*/
ErrMsg *_del_ErrMsg(ErrMsg *err)
{
if(err) {
free(err);
};
return NULL;
}
/*.......................................................................
* Record the concatenation of a list of string arguments in an error
* message object. The last argument must be END_ERR_MSG to terminate
* the argument list.
*
* Input:
* err ErrMsg * The error-message container.
* ... const char * Zero or more strings to be concatenated in buff[].
* ... const char * The last argument must always be END_ERR_MSG to
* terminate the argument list.
*/
void _err_record_msg(ErrMsg *err, ...)
{
va_list ap; /* The variable argument list */
const char *s; /* The string being printed */
size_t msglen = 0; /* The total length of the message */
/*
* Nowhere to record the result?
*/
if(!err) {
errno = EINVAL;
return;
};
/*
* Concatenate the list of argument strings in err->msg[].
*/
va_start(ap, err);
while((s = va_arg(ap, const char *)) != END_ERR_MSG) {
/*
* How much room is left in the output buffer (note that the output
* buffer has ERR_MSG_LEN+1 elements).
*/
int nleft = ERR_MSG_LEN - msglen;
/*
* How long is the next string to be appended?
*/
size_t slen = strlen(s);
/*
* If there is any room left, append as much of the string
* as will fit.
*/
if(nleft > 0) {
int nnew = slen < nleft ? slen : nleft;
strncpy(err->msg + msglen, s, nnew);
msglen += nnew;
};
};
va_end(ap);
/*
* Terminate the message.
*/
err->msg[msglen] = '\0';
return;
}
/*.......................................................................
* Return a pointer to the error message buffer.
*
* Input:
* err ErrMsg * The container of the error message buffer.
* Output:
* return char * The current error message, or NULL if err==NULL.
*/
char *_err_get_msg(ErrMsg *err)
{
return err ? err->msg : NULL;
}
/*.......................................................................
* Replace the current error message with an empty string.
*
* Input:
* err ErrMsg * The container of the error message buffer.
*/
void _err_clear_msg(ErrMsg *err)
{
if(err)
err->msg[0] = '\0';
}
