ds: add a new type "byte array producer"

Introduced to write bytes to a byte array with size checking.

common/utils/ds/CMakeLists.txt

@@ -1,5 +1,6 @@
 add_library(ds OBJECT
             byte_array.c
+            byte_array_producer.c
             seq_arr.c
 )
 

common/utils/ds/byte_array_producer.c

@@ -0,0 +1,64 @@
+/*
+ * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The OpenAirInterface Software Alliance licenses this file to You under
+ * the OAI Public License, Version 1.1  (the "License"); you may not use this file
+ * except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.openairinterface.org/?page_id=698
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *-------------------------------------------------------------------------------
+ * For more information about the OpenAirInterface (OAI) Software Alliance:
+ *      contact@openairinterface.org
+ */
+
+#include "byte_array_producer.h"
+
+/* create a byte array producer from an existing buffer */
+byte_array_producer_t byte_array_producer_from_buffer(uint8_t *buffer, int len)
+{
+  byte_array_producer_t result = { .b.len = len, .b.buf = buffer, .pos = 0 };
+  return result;
+}
+
+/* put a byte in a byte array if there is space
+ * returns 1 on success, 0 on error
+ */
+int byte_array_producer_put_byte(byte_array_producer_t *b, uint8_t byte)
+{
+  if (b->pos == b->b.len)
+    return 0;
+
+  b->b.buf[b->pos] = byte;
+  b->pos++;
+
+  return 1;
+}
+
+/* put an u32 number as big endian in a byte array if there is space
+ * returns 1 on success, 0 on error
+ */
+int byte_array_producer_put_u32_be(byte_array_producer_t *b, uint32_t v)
+{
+  return byte_array_producer_put_byte(b, (v >> 24) & 0xff)
+         && byte_array_producer_put_byte(b, (v >> 16) & 0xff)
+         && byte_array_producer_put_byte(b, (v >> 8) & 0xff)
+         && byte_array_producer_put_byte(b, v & 0xff);
+}
+
+/* put an u24 number as big endian in a byte array if there is space
+ * returns 1 on success, 0 on error
+ */
+int byte_array_producer_put_u24_be(byte_array_producer_t *b, uint32_t v)
+{
+  return byte_array_producer_put_byte(b, (v >> 16) & 0xff)
+         && byte_array_producer_put_byte(b, (v >> 8) & 0xff)
+         && byte_array_producer_put_byte(b, v & 0xff);
+}

common/utils/ds/byte_array_producer.h

@@ -0,0 +1,40 @@
+/*
+ * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The OpenAirInterface Software Alliance licenses this file to You under
+ * the OAI Public License, Version 1.1  (the "License"); you may not use this file
+ * except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.openairinterface.org/?page_id=698
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *-------------------------------------------------------------------------------
+ * For more information about the OpenAirInterface (OAI) Software Alliance:
+ *      contact@openairinterface.org
+ */
+
+#ifndef BYTE_ARRAY_PRODUCER_H
+#define BYTE_ARRAY_PRODUCER_H
+
+#include <stdint.h>
+
+#include "byte_array.h"
+
+typedef struct {
+  byte_array_t b;
+  size_t pos;
+} byte_array_producer_t;
+
+byte_array_producer_t byte_array_producer_from_buffer(uint8_t *buffer, int len);
+
+int byte_array_producer_put_byte(byte_array_producer_t *b, uint8_t v);
+int byte_array_producer_put_u32_be(byte_array_producer_t *b, uint32_t v);
+int byte_array_producer_put_u24_be(byte_array_producer_t *b, uint32_t v);
+
+#endif