/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2008-2009. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
/*
* Module: safe_string.c
*
* This is a bunch of generic string operation
* that are safe regarding buffer overflow.
*
* All string functions terminate the process with an error message
* on buffer overflow.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "safe_string.h"
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
static void string_overflow_handler(const char* format, ...)
{
va_list args;
va_start(args, format);
vfprintf(stderr,format,args);
va_end(args);
exit(1);
}
int vsn_printf(char* dst, size_t size, const char* format, va_list args)
{
int ret = vsnprintf(dst, size, format, args);
if (ret >= size || ret < 0) {
string_overflow_handler("Buffer truncated '%s'\n",dst);
}
return ret;
}
int sn_printf(char* dst, size_t size, const char* format, ...)
{
va_list args;
int ret;
va_start(args, format);
ret = vsn_printf(dst,size,format,args);
va_end(args);
return ret;
}
int strn_cpy(char* dst, size_t size, const char* src)
{
return sn_printf(dst,size,"%s",src);
}
int strn_cat(char* dst, size_t size, const char* src)
{
return strn_catf(dst,size,"%s",src);
}
int strn_catf(char* dst, size_t size, const char* format, ...)
{
int ret;
va_list args;
#ifdef _GNU_SOURCE
int len = strnlen(dst,size);
#else
int len = strlen(dst);
#endif
if (len >= size) {
string_overflow_handler("Buffer already overflowed '%.*s'\n",
size, dst);
}
va_start(args, format);
ret = vsn_printf(dst+len, size-len, format, args);
va_end(args);
return len+ret;
}
char* find_str(const char* haystack, int hsize, const char* needle)
{
int i = 0;
int nsize = strlen(needle);
hsize -= nsize - 1;
for (i=0; i<hsize; i++) {
if (haystack[i]==needle[0] && strncmp(haystack+i,needle,nsize)==0) {
return (char*)(haystack+i);
}
}
return NULL;
}
#ifndef HAVE_MEMMOVE
void* memmove(void *dest, const void *src, size_t n)
{
int i;
if (src > dest) {
for (i=0; i<n; i++) ((char*)dest)[i] = ((char*)src)[i];
}
else {
for (i=(int)(n-1); i>=0; i--) ((char*)dest)[i] = ((char*)src)[i];
}
return dest;
}
#endif /* HAVE_MEMMOVE */
