1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19
20 #include <tinycbor/cbor.h>
21 #include <tinycbor/cbor_buf_writer.h>
22
23 static inline int
would_overflow(struct cbor_buf_writer * cb,size_t len)24 would_overflow(struct cbor_buf_writer *cb, size_t len)
25 {
26 ptrdiff_t remaining = (ptrdiff_t)cb->end;
27 remaining -= (ptrdiff_t)cb->ptr;
28 remaining -= (ptrdiff_t)len;
29 return (remaining < 0);
30 }
31
32 int
cbor_buf_writer(struct cbor_encoder_writer * arg,const char * data,int len)33 cbor_buf_writer(struct cbor_encoder_writer *arg, const char *data, int len)
34 {
35 struct cbor_buf_writer *cb = (struct cbor_buf_writer *) arg;
36
37 if (would_overflow(cb, len)) {
38 return CborErrorOutOfMemory;
39 }
40
41 memcpy(cb->ptr, data, len);
42 cb->ptr += len;
43 cb->enc.bytes_written += len;
44 return CborNoError;
45 }
46
47 void
cbor_buf_writer_init(struct cbor_buf_writer * cb,uint8_t * buffer,size_t size)48 cbor_buf_writer_init(struct cbor_buf_writer *cb, uint8_t *buffer, size_t size)
49 {
50 cb->ptr = buffer;
51 cb->end = buffer + size;
52 cb->enc.bytes_written = 0;
53 cb->enc.write = cbor_buf_writer;
54 }
55
56 size_t
cbor_buf_writer_buffer_size(struct cbor_buf_writer * cb,const uint8_t * buffer)57 cbor_buf_writer_buffer_size(struct cbor_buf_writer *cb, const uint8_t *buffer)
58 {
59 return (size_t)(cb->ptr - buffer);
60 }
61
