Message builder: initial version

Author: AdamZvara

include/CMakeLists.txt

@@ -14,6 +14,7 @@ set(SUB_HEADERS
     ipfixcol2/message_garbage.h
     ipfixcol2/message_ipfix.h
     ipfixcol2/message_session.h
+    ipfixcol2/message_builder.h
     ipfixcol2/modifier.h
     ipfixcol2/plugins.h
     ipfixcol2/session.h

include/ipfixcol2.h

@@ -60,6 +60,7 @@
 #include <ipfixcol2/message_garbage.h>
 #include <ipfixcol2/message_session.h>
 #include <ipfixcol2/message_ipfix.h>
+#include <ipfixcol2/message_builder.h>
 
 #include <ipfixcol2/modifier.h>
 #include <ipfixcol2/plugins.h>

include/ipfixcol2/message_builder.h

@@ -0,0 +1,128 @@
+/**
+ * \file message_builder.h
+ * \author Adam Zvara <[email protected]>
+ * \brief Message builder (header file)
+ * \date 2023
+ */
+
+#ifndef IPX_MESSAGE_BUILDER_H
+#define IPX_MESSAGE_BUILDER_H
+
+#include <ipfixcol2/api.h>
+
+/** Internal declaration of message builder */
+typedef struct ipx_msg_builder ipx_msg_builder_t;
+
+/**
+ * \brief Create new message builder
+ *
+ * \return Pointer to new message builder, otherwise NULL (memory allocation error)
+ */
+IPX_API ipx_msg_builder_t *
+ipx_msg_builder_create();
+
+/**
+ * \brief Destroy message builder
+ *
+ * \warning This function does NOT free message pointer allocated in builder.
+ *  Raw message is usually freed by calling ipx_msg_ipfix_destroy() on created
+ *  wrapper or user can call ipx_msg_builder_free_raw() BEFORE destroying builder.
+ *
+ * \param[in] builder Message builder
+ */
+IPX_API void
+ipx_msg_builder_destroy(ipx_msg_builder_t *builder);
+
+/**
+ * \brief Free memory allocated for raw message in builder
+ *
+ * \param[in] builder Message builder
+ */
+IPX_API void
+ipx_msg_builder_free_raw(ipx_msg_builder_t *builder);
+
+/**
+ * \brief Get current maximum length of IPFIX message in builder
+ *
+ * \param[in] builder Message builder
+ * \return Maximum allowed size of IPFIX message in builder or 0 (builder is NULL)
+ */
+IPX_API size_t
+ipx_msg_builder_get_maxlength(const ipx_msg_builder_t *builder);
+
+/**
+ * \brief Set maximum length of new IPFIX message in builder
+ *
+ * \param[in] builder    Message builder
+ * \param[in] new_length New maximum length of IPFIX message
+ */
+IPX_API void
+ipx_msg_builder_set_maxlength(ipx_msg_builder_t *builder, const size_t new_length);
+
+/**
+ * \brief Start creating new IPFIX message
+ *
+ * This function allocates memory for new raw message and copies original message
+ * header into it. It MUST be called before trying to add sets/records into
+ * message builder.
+ *
+ * \note If hints are not given (e.g hints == 0), maxbytes is used as
+ *  allocation size for raw message
+ *
+ * \param[in] builder  Pointer to message builder
+ * \param[in] hdr      Original raw message header
+ * \param[in] maxbytes Maximum length of new message (without IPFIX header)
+ * \param[in] hints    Allocation size of new raw message
+ * \return #IPX_OK on success
+ * \return #IPX_ERR_ARG on invalid argument (NULL pointers or maxbytes < IPFIX header length)
+ * \return #IPX_ERR_NOMEM on failed memory allocation
+ */
+IPX_API int
+ipx_msg_builder_start(ipx_msg_builder_t *builder, const struct fds_ipfix_msg_hdr *hdr,
+    const uint32_t maxbytes, const uint32_t hints);
+
+/**
+ * \brief Add new set to IPFIX message
+ *
+ * \warning When message length exceeds maxbytes, ipx_msg_builder_end needs to be called
+ *  to create wrapper around message!
+ *
+ * \param[in] builder Pointer to builder
+ * \param[in] id      ID of new set
+ * \return #IPX_OK on success
+ * \return #IPX_ERR_DENIED when message length would exceed maxbytes
+ * \return #IPX_ERR_NOMEM on memory allocation error
+ */
+IPX_API int
+ipx_msg_builder_add_set(struct ipx_msg_builder *builder, const uint16_t id);
+
+/**
+ * \brief Add new data record to IPFIX message
+ *
+ * \warning When message length exceeds maxbytes, ipx_msg_builder_end needs to be called
+ *  to create wrapper around message!
+ * \note New set is added automatically, there is no need to call add_set before calling
+ *  this function
+ *
+ * \param[in] builder Pointer to message builder
+ * \param[in] record  Pointer to data record
+ * \return #IPX_OK on success
+ * \return #IPX_ERR_DENIED when message length would exceed maxbytes
+ * \return #IPX_ERR_NOMEM on memory allocation error
+ */
+IPX_API int
+ipx_msg_builder_add_drec(ipx_msg_builder_t *builder, const struct fds_drec *record);
+
+/**
+ * \brief Create wrapper around raw IPFIX message in message builder
+ *
+ * \param[in] builder    Pointer to message builder
+ * \param[in] plugin_ctx Plugin context
+ * \param[in] msg_ctx    Message context (from original IPFIX message)
+ * \return Pointer to allocated IPFIX wrapper or NULL
+ */
+IPX_API ipx_msg_ipfix_t *
+ipx_msg_builder_end(const ipx_msg_builder_t *builder, const ipx_ctx_t *plugin_ctx,
+    const struct ipx_msg_ctx *msg_ctx);
+
+#endif

src/core/CMakeLists.txt

@@ -44,6 +44,7 @@ set(CORE_SOURCE
     message_session.c
     message_terminate.c
     message_terminate.h
+    message_builder.c
     modifier.c
     modifier.h
     odid_range.c