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

/**
 * @file expstring.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_MISC_EXPSTRING_H
#define BADVPN_MISC_EXPSTRING_H

#include <stddef.h>

#include <misc/debug.h>
#include <misc/exparray.h>
#include <misc/bsize.h>

typedef struct {
    struct ExpArray arr;
    size_t n;
} ExpString;

static int ExpString_Init (ExpString *c);
static void ExpString_Free (ExpString *c);
static int ExpString_Append (ExpString *c, const char *str);
static int ExpString_AppendChar (ExpString *c, char ch);
static int ExpString_AppendByte (ExpString *c, uint8_t x);
static int ExpString_AppendBinary (ExpString *c, const uint8_t *data, size_t len);
static int ExpString_AppendZeros (ExpString *c, size_t len);
static char * ExpString_Get (ExpString *c);
static size_t ExpString_Length (ExpString *c);

int ExpString_Init (ExpString *c)
{
    if (!ExpArray_init(&c->arr, 1, 16)) {
        return 0;
    }
    
    c->n = 0;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

void ExpString_Free (ExpString *c)
{
    free(c->arr.v);
}

int ExpString_Append (ExpString *c, const char *str)
{
    ASSERT(str)
    
    size_t l = strlen(str);
    bsize_t newsize = bsize_add(bsize_fromsize(c->n), bsize_add(bsize_fromsize(l), bsize_fromint(1)));
    
    if (newsize.is_overflow || !ExpArray_resize(&c->arr, newsize.value)) {
        return 0;
    }
    
    memcpy((char *)c->arr.v + c->n, str, l);
    c->n += l;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

int ExpString_AppendChar (ExpString *c, char ch)
{
    ASSERT(ch != '\0')
    
    bsize_t newsize = bsize_add(bsize_fromsize(c->n), bsize_fromint(2));
    
    if (newsize.is_overflow || !ExpArray_resize(&c->arr, newsize.value)) {
        return 0;
    }
    
    ((char *)c->arr.v)[c->n] = ch;
    c->n++;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

int ExpString_AppendByte (ExpString *c, uint8_t x)
{
    bsize_t newsize = bsize_add(bsize_fromsize(c->n), bsize_fromint(2));
    
    if (newsize.is_overflow || !ExpArray_resize(&c->arr, newsize.value)) {
        return 0;
    }
    
    ((uint8_t *)c->arr.v)[c->n] = x;
    c->n++;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

int ExpString_AppendBinary (ExpString *c, const uint8_t *data, size_t len)
{
    bsize_t newsize = bsize_add(bsize_fromsize(c->n), bsize_add(bsize_fromsize(len), bsize_fromint(1)));
    
    if (newsize.is_overflow || !ExpArray_resize(&c->arr, newsize.value)) {
        return 0;
    }
    
    memcpy((char *)c->arr.v + c->n, data, len);
    c->n += len;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

int ExpString_AppendZeros (ExpString *c, size_t len)
{
    bsize_t newsize = bsize_add(bsize_fromsize(c->n), bsize_add(bsize_fromsize(len), bsize_fromint(1)));
    
    if (newsize.is_overflow || !ExpArray_resize(&c->arr, newsize.value)) {
        return 0;
    }
    
    memset((char *)c->arr.v + c->n, 0, len);
    c->n += len;
    ((char *)c->arr.v)[c->n] = '\0';
    
    return 1;
}

char * ExpString_Get (ExpString *c)
{
    return (char *)c->arr.v;
}

size_t ExpString_Length (ExpString *c)
{
    return c->n;
}

#endif