tor-android/external/badvpn_dns/misc/bstring.h

141 lines
3.9 KiB
C

/**
* @file bstring.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef BADVPN_BSTRING_H
#define BADVPN_BSTRING_H
#include <misc/debug.h>
#include <stdlib.h>
#include <string.h>
#define BSTRING_TYPE_STATIC 5
#define BSTRING_TYPE_DYNAMIC 7
#define BSTRING_TYPE_EXTERNAL 11
#define BSTRING_STATIC_SIZE 23
#define BSTRING_STATIC_MAX (BSTRING_STATIC_SIZE - 1)
typedef struct {
union {
struct {
char type;
char static_string[BSTRING_STATIC_SIZE];
} us;
struct {
char type;
char *dynamic_string;
} ud;
struct {
char type;
const char *external_string;
} ue;
} u;
} BString;
static void BString__assert (BString *o)
{
switch (o->u.us.type) {
case BSTRING_TYPE_STATIC:
case BSTRING_TYPE_DYNAMIC:
case BSTRING_TYPE_EXTERNAL:
return;
}
ASSERT(0);
}
static int BString_Init (BString *o, const char *str)
{
if (strlen(str) <= BSTRING_STATIC_MAX) {
strcpy(o->u.us.static_string, str);
o->u.us.type = BSTRING_TYPE_STATIC;
} else {
if (!(o->u.ud.dynamic_string = malloc(strlen(str) + 1))) {
return 0;
}
strcpy(o->u.ud.dynamic_string, str);
o->u.ud.type = BSTRING_TYPE_DYNAMIC;
}
BString__assert(o);
return 1;
}
static void BString_InitStatic (BString *o, const char *str)
{
ASSERT(strlen(str) <= BSTRING_STATIC_MAX)
strcpy(o->u.us.static_string, str);
o->u.us.type = BSTRING_TYPE_STATIC;
BString__assert(o);
}
static void BString_InitExternal (BString *o, const char *str)
{
o->u.ue.external_string = str;
o->u.ue.type = BSTRING_TYPE_EXTERNAL;
BString__assert(o);
}
static void BString_InitAllocated (BString *o, char *str)
{
o->u.ud.dynamic_string = str;
o->u.ud.type = BSTRING_TYPE_DYNAMIC;
BString__assert(o);
}
static void BString_Free (BString *o)
{
BString__assert(o);
if (o->u.ud.type == BSTRING_TYPE_DYNAMIC) {
free(o->u.ud.dynamic_string);
}
}
static const char * BString_Get (BString *o)
{
BString__assert(o);
switch (o->u.us.type) {
case BSTRING_TYPE_STATIC: return o->u.us.static_string;
case BSTRING_TYPE_DYNAMIC: return o->u.ud.dynamic_string;
case BSTRING_TYPE_EXTERNAL: return o->u.ue.external_string;
}
ASSERT(0);
return NULL;
}
#endif