forked from Unidata/netcdf-c
/
d4bytes.c
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/
d4bytes.c
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/* Copyright 2009, UCAR/Unidata and OPeNDAP, Inc.
See the COPYRIGHT file for more information. */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "config.h"
#include "d4util.h"
#include "d4bytes.h"
#define DEFAULTMINALLOC 8
D4bytes*
d4bytesnew(void)
{
D4bytes* d4m = (D4bytes*)malloc(sizeof(D4bytes));
if(d4m == NULL) return NULL;
d4m->alloc=0;
d4m->used=0;
d4m->memory=NULL;
return d4m;
}
void
d4bytesfree(D4bytes* d4m)
{
if(d4m == NULL) return;
if(d4m->memory != NULL) free(d4m->memory);
free(d4m);
}
void*
d4bytesalloc(D4bytes* d4m, size_t sz)
{
void* allocation;
size_t newalloc;
if(sz == 0 || d4m == NULL) return NULL;
newalloc = d4m->alloc;
if(newalloc == 0) newalloc = DEFAULTMINALLOC;
for(;;) {
size_t avail = newalloc - d4m->used;
if(avail >= sz) { /* rebuild */
void* newmem = realloc(d4m->memory,newalloc);
d4m->memory = newmem;
d4m->alloc = newalloc;
break;
}
newalloc = (2*newalloc); /* keep doubling */
}
allocation = (void*)(((char*)d4m->memory)+d4m->used);
d4m->used += sz;
return allocation;
}
void*
d4byteszero(D4bytes* d4m, size_t sz)
{
void* mem = d4bytesalloc(d4m,sz);
memset(mem,0,sz);
return mem;
}
D4bytes*
d4bytesconcat(D4bytes* dst, D4bytes* src)
{
if(dst == NULL && src != NULL && src->used > 0) {
void* target = d4bytesalloc(dst,src->used);
d4memmove(target,src->memory,src->used);
}
return dst;
}