monero/external/unbound/ldns/sbuffer.c
2014-10-05 23:44:31 +02:00

178 lines
3.6 KiB
C

/*
* buffer.c -- generic memory buffer .
*
* Copyright (c) 2001-2008, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/
/**
* \file
*
* This file contains the definition of sldns_buffer, and functions to manipulate those.
*/
#include "config.h"
#include "ldns/sbuffer.h"
#include <stdarg.h>
sldns_buffer *
sldns_buffer_new(size_t capacity)
{
sldns_buffer *buffer = (sldns_buffer*)malloc(sizeof(sldns_buffer));
if (!buffer) {
return NULL;
}
buffer->_data = (uint8_t *) malloc(capacity);
if (!buffer->_data) {
free(buffer);
return NULL;
}
buffer->_position = 0;
buffer->_limit = buffer->_capacity = capacity;
buffer->_fixed = 0;
buffer->_status_err = 0;
sldns_buffer_invariant(buffer);
return buffer;
}
void
sldns_buffer_new_frm_data(sldns_buffer *buffer, void *data, size_t size)
{
assert(data != NULL);
buffer->_position = 0;
buffer->_limit = buffer->_capacity = size;
buffer->_fixed = 0;
buffer->_data = malloc(size);
if(!buffer->_data) {
buffer->_status_err = 1;
return;
}
memcpy(buffer->_data, data, size);
buffer->_status_err = 0;
sldns_buffer_invariant(buffer);
}
void
sldns_buffer_init_frm_data(sldns_buffer *buffer, void *data, size_t size)
{
memset(buffer, 0, sizeof(*buffer));
buffer->_data = data;
buffer->_capacity = buffer->_limit = size;
buffer->_fixed = 1;
}
int
sldns_buffer_set_capacity(sldns_buffer *buffer, size_t capacity)
{
void *data;
sldns_buffer_invariant(buffer);
assert(buffer->_position <= capacity);
data = (uint8_t *) realloc(buffer->_data, capacity);
if (!data) {
buffer->_status_err = 1;
return 0;
} else {
buffer->_data = data;
buffer->_limit = buffer->_capacity = capacity;
return 1;
}
}
int
sldns_buffer_reserve(sldns_buffer *buffer, size_t amount)
{
sldns_buffer_invariant(buffer);
assert(!buffer->_fixed);
if (buffer->_capacity < buffer->_position + amount) {
size_t new_capacity = buffer->_capacity * 3 / 2;
if (new_capacity < buffer->_position + amount) {
new_capacity = buffer->_position + amount;
}
if (!sldns_buffer_set_capacity(buffer, new_capacity)) {
buffer->_status_err = 1;
return 0;
}
}
buffer->_limit = buffer->_capacity;
return 1;
}
int
sldns_buffer_printf(sldns_buffer *buffer, const char *format, ...)
{
va_list args;
int written = 0;
size_t remaining;
if (sldns_buffer_status_ok(buffer)) {
sldns_buffer_invariant(buffer);
assert(buffer->_limit == buffer->_capacity);
remaining = sldns_buffer_remaining(buffer);
va_start(args, format);
written = vsnprintf((char *) sldns_buffer_current(buffer), remaining,
format, args);
va_end(args);
if (written == -1) {
buffer->_status_err = 1;
return -1;
} else if ((size_t) written >= remaining) {
if (!sldns_buffer_reserve(buffer, (size_t) written + 1)) {
buffer->_status_err = 1;
return -1;
}
va_start(args, format);
written = vsnprintf((char *) sldns_buffer_current(buffer),
sldns_buffer_remaining(buffer), format, args);
va_end(args);
if (written == -1) {
buffer->_status_err = 1;
return -1;
}
}
buffer->_position += written;
}
return written;
}
void
sldns_buffer_free(sldns_buffer *buffer)
{
if (!buffer) {
return;
}
if (!buffer->_fixed)
free(buffer->_data);
free(buffer);
}
void *
sldns_buffer_export(sldns_buffer *buffer)
{
buffer->_fixed = 1;
return buffer->_data;
}
void
sldns_buffer_copy(sldns_buffer* result, sldns_buffer* from)
{
size_t tocopy = sldns_buffer_limit(from);
if(tocopy > sldns_buffer_capacity(result))
tocopy = sldns_buffer_capacity(result);
sldns_buffer_clear(result);
sldns_buffer_write(result, sldns_buffer_begin(from), tocopy);
sldns_buffer_flip(result);
}