bdberl/c_src/bin_helper.c

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/* -------------------------------------------------------------------
*
* bin_helper: ErlDrvBinary helper functions
* Copyright (c) 2008 The Hive. All rights reserved.
*
* ------------------------------------------------------------------- */
#include "bin_helper.h"
#include <string.h>
#include <stdlib.h>
static void bin_helper_check_size(BinHelper* bh, int space_needed)
{
if (bh->offset + space_needed > bh->bin->orig_size)
{
// Need to realloc space -- grow by 2 * space_needed
bh->bin = driver_realloc_binary(bh->bin, bh->bin->orig_size + (2 * space_needed));
}
}
void bin_helper_init(BinHelper* bh, unsigned int size)
{
bh->bin = driver_alloc_binary(size);
bh->offset = 0;
}
void bin_helper_push_byte(BinHelper* bh, int value)
{
bin_helper_check_size(bh, 1);
bh->bin->orig_bytes[bh->offset] = (char)value;
bh->offset++;
}
void bin_helper_push_int32(BinHelper* bh, int value)
{
bin_helper_check_size(bh, 4);
memcpy(bh->bin->orig_bytes+(bh->offset), (char*)&value, 4);
bh->offset += 4;
}
void bin_helper_push_string(BinHelper* bh, const char* string)
{
int sz = strlen(string);
bin_helper_check_size(bh, sz+1);
strncpy(bh->bin->orig_bytes+(bh->offset), string, sz+1);
bh->offset += sz + 1;
}