A small memory footprint AMQP implimentation
Dependents: iothub_client_sample_amqp remote_monitoring simplesample_amqp
frame_codec.c
- Committer:
- AzureIoTClient
- Date:
- 2017-01-08
- Revision:
- 15:5db103709f20
- Parent:
- 12:b30dacf113f2
- Child:
- 16:22a72cf8e416
File content as of revision 15:5db103709f20:
// Copyright (c) Microsoft. All rights reserved. // Licensed under the MIT license. See LICENSE file in the project root for full license information. #include <stdlib.h> #ifdef _CRTDBG_MAP_ALLOC #include <crtdbg.h> #endif #include <stdint.h> #include <stdbool.h> #include <string.h> #include "azure_c_shared_utility/xlogging.h" #include "azure_c_shared_utility/xio.h" #include "azure_c_shared_utility/singlylinkedlist.h" #include "azure_uamqp_c/frame_codec.h" #include "azure_uamqp_c/amqpvalue.h" #include "azure_uamqp_c/amqpalloc.h" #define FRAME_HEADER_SIZE 8 #define MAX_TYPE_SPECIFIC_SIZE ((255 * 4) - 6) typedef enum RECEIVE_FRAME_STATE_TAG { RECEIVE_FRAME_STATE_FRAME_SIZE, RECEIVE_FRAME_STATE_DOFF, RECEIVE_FRAME_STATE_FRAME_TYPE, RECEIVE_FRAME_STATE_TYPE_SPECIFIC, RECEIVE_FRAME_STATE_FRAME_BODY, RECEIVE_FRAME_STATE_ERROR } RECEIVE_FRAME_STATE; typedef enum ENCODE_FRAME_STATE_TAG { ENCODE_FRAME_STATE_IDLE, ENCODE_FRAME_STATE_ERROR } ENCODE_FRAME_STATE; typedef struct SUBSCRIPTION_TAG { uint8_t frame_type; ON_FRAME_RECEIVED on_frame_received; void* callback_context; } SUBSCRIPTION; typedef struct FRAME_CODEC_INSTANCE_TAG { /* subscriptions */ SINGLYLINKEDLIST_HANDLE subscription_list; /* decode frame */ RECEIVE_FRAME_STATE receive_frame_state; size_t receive_frame_pos; uint32_t receive_frame_size; uint32_t type_specific_size; uint8_t receive_frame_doff; uint8_t receive_frame_type; SUBSCRIPTION* receive_frame_subscription; unsigned char* receive_frame_bytes; ON_FRAME_CODEC_ERROR on_frame_codec_error; void* on_frame_codec_error_callback_context; /* encode frame */ ENCODE_FRAME_STATE encode_frame_state; /* configuration */ uint32_t max_frame_size; } FRAME_CODEC_INSTANCE; static bool find_subscription_by_frame_type(LIST_ITEM_HANDLE list_item, const void* match_context) { bool result; SUBSCRIPTION* subscription = (SUBSCRIPTION*)singlylinkedlist_item_get_value(list_item); if (subscription == NULL) { result = false; } else { result = subscription->frame_type == *((uint8_t*)match_context) ? true : false; } return result; } FRAME_CODEC_HANDLE frame_codec_create(ON_FRAME_CODEC_ERROR on_frame_codec_error, void* callback_context) { FRAME_CODEC_INSTANCE* result; /* Codes_SRS_FRAME_CODEC_01_020: [If the on_frame_codec_error argument is NULL, frame_codec_create shall return NULL.] */ /* Codes_SRS_FRAME_CODEC_01_104: [The callback_context shall be allowed to be NULL.] */ if (on_frame_codec_error == NULL) { result = NULL; } else { result = amqpalloc_malloc(sizeof(FRAME_CODEC_INSTANCE)); /* Codes_SRS_FRAME_CODEC_01_022: [If allocating memory for the frame_codec instance fails, frame_codec_create shall return NULL.] */ if (result != NULL) { /* Codes_SRS_FRAME_CODEC_01_021: [frame_codec_create shall create a new instance of frame_codec and return a non-NULL handle to it on success.] */ result->encode_frame_state = ENCODE_FRAME_STATE_IDLE; result->receive_frame_state = RECEIVE_FRAME_STATE_FRAME_SIZE; result->on_frame_codec_error = on_frame_codec_error; result->on_frame_codec_error_callback_context = callback_context; result->receive_frame_pos = 0; result->receive_frame_size = 0; result->receive_frame_bytes = NULL; result->subscription_list = singlylinkedlist_create(); /* Codes_SRS_FRAME_CODEC_01_082: [The initial max_frame_size_shall be 512.] */ result->max_frame_size = 512; } } return result; } void frame_codec_destroy(FRAME_CODEC_HANDLE frame_codec) { /* Codes_SRS_FRAME_CODEC_01_024: [If frame_codec is NULL, frame_codec_destroy shall do nothing.] */ if (frame_codec != NULL) { FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; singlylinkedlist_destroy(frame_codec_data->subscription_list); if (frame_codec_data->receive_frame_bytes != NULL) { amqpalloc_free(frame_codec_data->receive_frame_bytes); } /* Codes_SRS_FRAME_CODEC_01_023: [frame_codec_destroy shall free all resources associated with a frame_codec instance.] */ amqpalloc_free(frame_codec); } } int frame_codec_set_max_frame_size(FRAME_CODEC_HANDLE frame_codec, uint32_t max_frame_size) { int result; FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; /* Codes_SRS_FRAME_CODEC_01_077: [If frame_codec is NULL, frame_codec_set_max_frame_size shall return a non-zero value.] */ if ((frame_codec == NULL) || /* Codes_SRS_FRAME_CODEC_01_078: [If max_frame_size is invalid according to the AMQP standard, frame_codec_set_max_frame_size shall return a non-zero value.] */ (max_frame_size < FRAME_HEADER_SIZE) || /* Codes_SRS_FRAME_CODEC_01_081: [If a frame being decoded already has a size bigger than the max_frame_size argument then frame_codec_set_max_frame_size shall return a non-zero value and the previous frame size shall be kept.] */ ((max_frame_size < frame_codec_data->receive_frame_size) && (frame_codec_data->receive_frame_state != RECEIVE_FRAME_STATE_FRAME_SIZE)) || /* Codes_SRS_FRAME_CODEC_01_097: [Setting a frame size on a frame_codec that had a decode error shall fail.] */ (frame_codec_data->receive_frame_state == RECEIVE_FRAME_STATE_ERROR) || /* Codes_SRS_FRAME_CODEC_01_098: [Setting a frame size on a frame_codec that had an encode error shall fail.] */ (frame_codec_data->encode_frame_state == ENCODE_FRAME_STATE_ERROR)) { result = __LINE__; } else { /* Codes_SRS_FRAME_CODEC_01_075: [frame_codec_set_max_frame_size shall set the maximum frame size for a frame_codec.] */ /* Codes_SRS_FRAME_CODEC_01_079: [The new frame size shall take effect immediately, even for a frame that is being decoded at the time of the call.] */ frame_codec_data->max_frame_size = max_frame_size; /* Codes_SRS_FRAME_CODEC_01_076: [On success, frame_codec_set_max_frame_size shall return 0.] */ result = 0; } return result; } /* Codes_SRS_FRAME_CODEC_01_001: [Frames are divided into three distinct areas: a fixed width frame header, a variable width extended header, and a variable width frame body.] */ /* Codes_SRS_FRAME_CODEC_01_002: [frame header The frame header is a fixed size (8 byte) structure that precedes each frame.] */ /* Codes_SRS_FRAME_CODEC_01_003: [The frame header includes mandatory information necessary to parse the rest of the frame including size and type information.] */ /* Codes_SRS_FRAME_CODEC_01_004: [extended header The extended header is a variable width area preceding the frame body.] */ /* Codes_SRS_FRAME_CODEC_01_007: [frame body The frame body is a variable width sequence of bytes the format of which depends on the frame type.] */ /* Codes_SRS_FRAME_CODEC_01_028: [The sequence of bytes shall be decoded according to the AMQP ISO.] */ /* Codes_SRS_FRAME_CODEC_01_029: [The sequence of bytes does not have to be a complete frame, frame_codec shall be responsible for maintaining decoding state between frame_codec_receive_bytes calls.] */ int frame_codec_receive_bytes(FRAME_CODEC_HANDLE frame_codec, const unsigned char* buffer, size_t size) { int result = __LINE__; FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; /* Codes_SRS_FRAME_CODEC_01_026: [If frame_codec or buffer are NULL, frame_codec_receive_bytes shall return a non-zero value.] */ if ((frame_codec == NULL) || (buffer == NULL) || /* Codes_SRS_FRAME_CODEC_01_027: [If size is zero, frame_codec_receive_bytes shall return a non-zero value.] */ (size == 0)) { result = __LINE__; } else { while (size > 0) { switch (frame_codec_data->receive_frame_state) { default: case RECEIVE_FRAME_STATE_ERROR: /* Codes_SRS_FRAME_CODEC_01_074: [If a decoding error is detected, any subsequent calls on frame_codec_data_receive_bytes shall fail.] */ result = __LINE__; size = 0; break; /* Codes_SRS_FRAME_CODEC_01_008: [SIZE Bytes 0-3 of the frame header contain the frame size.] */ case RECEIVE_FRAME_STATE_FRAME_SIZE: /* Codes_SRS_FRAME_CODEC_01_009: [This is an unsigned 32-bit integer that MUST contain the total frame size of the frame header, extended header, and frame body.] */ frame_codec_data->receive_frame_size += buffer[0] << (24 - frame_codec_data->receive_frame_pos * 8); buffer++; size--; frame_codec_data->receive_frame_pos++; if (frame_codec_data->receive_frame_pos == 4) { /* Codes_SRS_FRAME_CODEC_01_010: [The frame is malformed if the size is less than the size of the frame header (8 bytes).] */ if ((frame_codec_data->receive_frame_size < FRAME_HEADER_SIZE) || /* Codes_SRS_FRAME_CODEC_01_096: [If a frame bigger than the current max frame size is received, frame_codec_receive_bytes shall fail and return a non-zero value.] */ (frame_codec_data->receive_frame_size > frame_codec_data->max_frame_size)) { /* Codes_SRS_FRAME_CODEC_01_074: [If a decoding error is detected, any subsequent calls on frame_codec_data_receive_bytes shall fail.] */ frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_ERROR; /* Codes_SRS_FRAME_CODEC_01_103: [Upon any decode error, if an error callback has been passed to frame_codec_create, then the error callback shall be called with the context argument being the on_frame_codec_error_callback_context argument passed to frame_codec_create.] */ frame_codec_data->on_frame_codec_error(frame_codec_data->on_frame_codec_error_callback_context); result = __LINE__; } else { frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_DOFF; result = 0; } } else { result = 0; } break; case RECEIVE_FRAME_STATE_DOFF: /* Codes_SRS_FRAME_CODEC_01_011: [DOFF Byte 4 of the frame header is the data offset.] */ /* Codes_SRS_FRAME_CODEC_01_013: [The value of the data offset is an unsigned, 8-bit integer specifying a count of 4-byte words.] */ /* Codes_SRS_FRAME_CODEC_01_012: [This gives the position of the body within the frame.] */ frame_codec_data->receive_frame_doff = buffer[0]; buffer++; size--; /* Codes_SRS_FRAME_CODEC_01_014: [Due to the mandatory 8-byte frame header, the frame is malformed if the value is less than 2.] */ if (frame_codec_data->receive_frame_doff < 2) { /* Codes_SRS_FRAME_CODEC_01_074: [If a decoding error is detected, any subsequent calls on frame_codec_data_receive_bytes shall fail.] */ frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_ERROR; /* Codes_SRS_FRAME_CODEC_01_103: [Upon any decode error, if an error callback has been passed to frame_codec_create, then the error callback shall be called with the context argument being the on_frame_codec_error_callback_context argument passed to frame_codec_create.] */ frame_codec_data->on_frame_codec_error(frame_codec_data->on_frame_codec_error_callback_context); result = __LINE__; } else { frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_FRAME_TYPE; result = 0; } break; case RECEIVE_FRAME_STATE_FRAME_TYPE: { LIST_ITEM_HANDLE item_handle; frame_codec_data->type_specific_size = (frame_codec_data->receive_frame_doff * 4) - 6; /* Codes_SRS_FRAME_CODEC_01_015: [TYPE Byte 5 of the frame header is a type code.] */ frame_codec_data->receive_frame_type = buffer[0]; buffer++; size--; /* Codes_SRS_FRAME_CODEC_01_035: [After successfully registering a callback for a certain frame type, when subsequently that frame type is received the callbacks shall be invoked, passing to it the received frame and the callback_context value.] */ item_handle = singlylinkedlist_find(frame_codec_data->subscription_list, find_subscription_by_frame_type, &frame_codec_data->receive_frame_type); if (item_handle == NULL) { frame_codec_data->receive_frame_subscription = NULL; frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_TYPE_SPECIFIC; result = 0; break; } else { frame_codec_data->receive_frame_subscription = (SUBSCRIPTION*)singlylinkedlist_item_get_value(item_handle); if (frame_codec_data->receive_frame_subscription == NULL) { frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_TYPE_SPECIFIC; result = 0; break; } else { frame_codec_data->receive_frame_pos = 0; /* Codes_SRS_FRAME_CODEC_01_102: [frame_codec_receive_bytes shall allocate memory to hold the frame_body bytes.] */ frame_codec_data->receive_frame_bytes = (unsigned char*)amqpalloc_malloc(frame_codec_data->receive_frame_size - 6); if (frame_codec_data->receive_frame_bytes == NULL) { /* Codes_SRS_FRAME_CODEC_01_101: [If the memory for the frame_body bytes cannot be allocated, frame_codec_receive_bytes shall fail and return a non-zero value.] */ /* Codes_SRS_FRAME_CODEC_01_030: [If a decoding error occurs, frame_codec_data_receive_bytes shall return a non-zero value.] */ /* Codes_SRS_FRAME_CODEC_01_074: [If a decoding error is detected, any subsequent calls on frame_codec_data_receive_bytes shall fail.] */ frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_ERROR; /* Codes_SRS_FRAME_CODEC_01_103: [Upon any decode error, if an error callback has been passed to frame_codec_create, then the error callback shall be called with the context argument being the on_frame_codec_error_callback_context argument passed to frame_codec_create.] */ frame_codec_data->on_frame_codec_error(frame_codec_data->on_frame_codec_error_callback_context); result = __LINE__; break; } else { frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_TYPE_SPECIFIC; result = 0; break; } } } } case RECEIVE_FRAME_STATE_TYPE_SPECIFIC: { size_t to_copy = frame_codec_data->type_specific_size - frame_codec_data->receive_frame_pos; if (to_copy > size) { to_copy = size; } if (frame_codec_data->receive_frame_subscription != NULL) { (void)memcpy(&frame_codec_data->receive_frame_bytes[frame_codec_data->receive_frame_pos], buffer, to_copy); frame_codec_data->receive_frame_pos += to_copy; buffer += to_copy; size -= to_copy; } else { frame_codec_data->receive_frame_pos += to_copy; buffer += to_copy; size -= to_copy; } if (frame_codec_data->receive_frame_pos == frame_codec_data->type_specific_size) { if (frame_codec_data->receive_frame_size == FRAME_HEADER_SIZE) { if (frame_codec_data->receive_frame_subscription != NULL) { /* Codes_SRS_FRAME_CODEC_01_031: [When a complete frame is successfully decoded it shall be indicated to the upper layer by invoking the on_frame_received passed to frame_codec_subscribe.] */ /* Codes_SRS_FRAME_CODEC_01_032: [Besides passing the frame information, the callback_context value passed to frame_codec_data_subscribe shall be passed to the on_frame_received function.] */ /* Codes_SRS_FRAME_CODEC_01_005: [This is an extension point defined for future expansion.] */ /* Codes_SRS_FRAME_CODEC_01_006: [The treatment of this area depends on the frame type.] */ /* Codes_SRS_FRAME_CODEC_01_100: [If the frame body size is 0, the frame_body pointer passed to on_frame_received shall be NULL.] */ frame_codec_data->receive_frame_subscription->on_frame_received(frame_codec_data->receive_frame_subscription->callback_context, frame_codec_data->receive_frame_bytes, frame_codec_data->type_specific_size, NULL, 0); amqpalloc_free(frame_codec_data->receive_frame_bytes); frame_codec_data->receive_frame_bytes = NULL; } frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_FRAME_SIZE; frame_codec_data->receive_frame_size = 0; } else { frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_FRAME_BODY; } frame_codec_data->receive_frame_pos = 0; } result = 0; break; } case RECEIVE_FRAME_STATE_FRAME_BODY: { uint32_t frame_body_size = frame_codec_data->receive_frame_size - (frame_codec_data->receive_frame_doff * 4); size_t to_copy = frame_body_size - frame_codec_data->receive_frame_pos; if (to_copy > size) { to_copy = size; } (void)memcpy(frame_codec_data->receive_frame_bytes + frame_codec_data->receive_frame_pos + frame_codec_data->type_specific_size, buffer, to_copy); buffer += to_copy; size -= to_copy; frame_codec_data->receive_frame_pos += to_copy; if (frame_codec_data->receive_frame_pos == frame_body_size) { if (frame_codec_data->receive_frame_subscription != NULL) { /* Codes_SRS_FRAME_CODEC_01_031: [When a complete frame is successfully decoded it shall be indicated to the upper layer by invoking the on_frame_received passed to frame_codec_subscribe.] */ /* Codes_SRS_FRAME_CODEC_01_032: [Besides passing the frame information, the callback_context value passed to frame_codec_data_subscribe shall be passed to the on_frame_received function.] */ /* Codes_SRS_FRAME_CODEC_01_005: [This is an extension point defined for future expansion.] */ /* Codes_SRS_FRAME_CODEC_01_006: [The treatment of this area depends on the frame type.] */ /* Codes_SRS_FRAME_CODEC_01_099: [A pointer to the frame_body bytes shall also be passed to the on_frame_received.] */ frame_codec_data->receive_frame_subscription->on_frame_received(frame_codec_data->receive_frame_subscription->callback_context, frame_codec_data->receive_frame_bytes, frame_codec_data->type_specific_size, frame_codec_data->receive_frame_bytes + frame_codec_data->type_specific_size, frame_body_size); amqpalloc_free(frame_codec_data->receive_frame_bytes); frame_codec_data->receive_frame_bytes = NULL; } frame_codec_data->receive_frame_state = RECEIVE_FRAME_STATE_FRAME_SIZE; frame_codec_data->receive_frame_pos = 0; frame_codec_data->receive_frame_size = 0; } result = 0; break; } } } } return result; } /* Codes_SRS_FRAME_CODEC_01_033: [frame_codec_subscribe subscribes for a certain type of frame received by the frame_codec instance identified by frame_codec.] */ int frame_codec_subscribe(FRAME_CODEC_HANDLE frame_codec, uint8_t type, ON_FRAME_RECEIVED on_frame_received, void* callback_context) { int result; /* Codes_SRS_FRAME_CODEC_01_034: [If any of the frame_codec or on_frame_received arguments is NULL, frame_codec_subscribe shall return a non-zero value.] */ if ((frame_codec == NULL) || (on_frame_received == NULL)) { result = __LINE__; } else { FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; SUBSCRIPTION* subscription; /* Codes_SRS_FRAME_CODEC_01_036: [Only one callback pair shall be allowed to be registered for a given frame type.] */ /* find the subscription for this frame type */ LIST_ITEM_HANDLE list_item = singlylinkedlist_find(frame_codec_data->subscription_list, find_subscription_by_frame_type, &type); if (list_item != NULL) { subscription = (SUBSCRIPTION*)singlylinkedlist_item_get_value(list_item); if (subscription == NULL) { /* Codes_SRS_FRAME_CODEC_01_037: [If any failure occurs while performing the subscribe operation, frame_codec_subscribe shall return a non-zero value.] */ result = __LINE__; } else { /* a subscription was found */ subscription->on_frame_received = on_frame_received; subscription->callback_context = callback_context; /* Codes_SRS_FRAME_CODEC_01_087: [On success, frame_codec_subscribe shall return zero.] */ result = 0; } } else { /* add a new subscription */ subscription = (SUBSCRIPTION*)amqpalloc_malloc(sizeof(SUBSCRIPTION)); /* Codes_SRS_FRAME_CODEC_01_037: [If any failure occurs while performing the subscribe operation, frame_codec_subscribe shall return a non-zero value.] */ if (subscription == NULL) { result = __LINE__; } else { subscription->on_frame_received = on_frame_received; subscription->callback_context = callback_context; subscription->frame_type = type; /* Codes_SRS_FRAME_CODEC_01_037: [If any failure occurs while performing the subscribe operation, frame_codec_subscribe shall return a non-zero value.] */ if (singlylinkedlist_add(frame_codec_data->subscription_list, subscription) == NULL) { amqpalloc_free(subscription); result = __LINE__; } else { /* Codes_SRS_FRAME_CODEC_01_087: [On success, frame_codec_subscribe shall return zero.] */ result = 0; } } } } return result; } int frame_codec_unsubscribe(FRAME_CODEC_HANDLE frame_codec, uint8_t type) { int result; /* Codes_SRS_FRAME_CODEC_01_039: [If frame_codec is NULL, frame_codec_unsubscribe shall return a non-zero value.] */ if (frame_codec == NULL) { result = __LINE__; } else { FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; LIST_ITEM_HANDLE list_item = singlylinkedlist_find(frame_codec_data->subscription_list, find_subscription_by_frame_type, &type); if (list_item == NULL) { /* Codes_SRS_FRAME_CODEC_01_040: [If no subscription for the type frame type exists, frame_codec_unsubscribe shall return a non-zero value.] */ /* Codes_SRS_FRAME_CODEC_01_041: [If any failure occurs while performing the unsubscribe operation, frame_codec_unsubscribe shall return a non-zero value.] */ result = __LINE__; } else { SUBSCRIPTION* subscription = (SUBSCRIPTION*)singlylinkedlist_item_get_value(list_item); if (subscription == NULL) { /* Codes_SRS_FRAME_CODEC_01_041: [If any failure occurs while performing the unsubscribe operation, frame_codec_unsubscribe shall return a non-zero value.] */ result = __LINE__; } else { amqpalloc_free(subscription); if (singlylinkedlist_remove(frame_codec_data->subscription_list, list_item) != 0) { /* Codes_SRS_FRAME_CODEC_01_041: [If any failure occurs while performing the unsubscribe operation, frame_codec_unsubscribe shall return a non-zero value.] */ result = __LINE__; } else { /* Codes_SRS_FRAME_CODEC_01_038: [frame_codec_unsubscribe removes a previous subscription for frames of type type and on success it shall return 0.] */ result = 0; } } } } return result; } int frame_codec_encode_frame(FRAME_CODEC_HANDLE frame_codec, uint8_t type, const PAYLOAD* payloads, size_t payload_count, const unsigned char* type_specific_bytes, uint32_t type_specific_size, ON_BYTES_ENCODED on_bytes_encoded, void* callback_context) { int result; FRAME_CODEC_INSTANCE* frame_codec_data = (FRAME_CODEC_INSTANCE*)frame_codec; /* Codes_SRS_FRAME_CODEC_01_044: [If the argument frame_codec is NULL, frame_codec_encode_frame shall return a non-zero value.] */ if ((frame_codec == NULL) || /* Codes_SRS_FRAME_CODEC_01_091: [If the argument type_specific_size is greater than 0 and type_specific_bytes is NULL, frame_codec_encode_frame shall return a non-zero value.] */ ((type_specific_size > 0) && (type_specific_bytes == NULL)) || /* Codes_SRS_FRAME_CODEC_01_092: [If type_specific_size is too big to allow encoding the frame according to the AMQP ISO then frame_codec_encode_frame shall return a non-zero value.] */ (type_specific_size > MAX_TYPE_SPECIFIC_SIZE) || (frame_codec_data->encode_frame_state == ENCODE_FRAME_STATE_ERROR)) { result = __LINE__; } else { /* round up to the 4 bytes for doff */ /* Codes_SRS_FRAME_CODEC_01_067: [The value of the data offset is an unsigned, 8-bit integer specifying a count of 4-byte words.] */ /* Codes_SRS_FRAME_CODEC_01_068: [Due to the mandatory 8-byte frame header, the frame is malformed if the value is less than 2.] */ uint8_t padding_byte_count; uint32_t frame_body_offset = type_specific_size + 6; uint8_t doff = (uint8_t)((frame_body_offset + 3) / 4); size_t i; size_t frame_size; size_t frame_body_size = 0; frame_body_offset = doff * 4; padding_byte_count = (uint8_t)(frame_body_offset - type_specific_size - 6); for (i = 0; i < payload_count; i++) { frame_body_size += payloads[i].length; } /* Codes_SRS_FRAME_CODEC_01_063: [This is an unsigned 32-bit integer that MUST contain the total frame size of the frame header, extended header, and frame body.] */ frame_size = frame_body_size + frame_body_offset; if (frame_size > frame_codec_data->max_frame_size) { /* Codes_SRS_FRAME_CODEC_01_095: [If the frame_size needed for the frame is bigger than the maximum frame size, frame_codec_encode_frame shall fail and return a non-zero value.] */ result = __LINE__; } else { /* Codes_SRS_FRAME_CODEC_01_042: [frame_codec_encode_frame encodes the header and type specific bytes of a frame that has frame_payload_size bytes.] */ /* Codes_SRS_FRAME_CODEC_01_055: [Frames are divided into three distinct areas: a fixed width frame header, a variable width extended header, and a variable width frame body.] */ /* Codes_SRS_FRAME_CODEC_01_056: [frame header The frame header is a fixed size (8 byte) structure that precedes each frame.] */ /* Codes_SRS_FRAME_CODEC_01_057: [The frame header includes mandatory information necessary to parse the rest of the frame including size and type information.] */ /* Codes_SRS_FRAME_CODEC_01_058: [extended header The extended header is a variable width area preceding the frame body.] */ /* Codes_SRS_FRAME_CODEC_01_059: [This is an extension point defined for future expansion.] */ /* Codes_SRS_FRAME_CODEC_01_060: [The treatment of this area depends on the frame type.]*/ /* Codes_SRS_FRAME_CODEC_01_062: [SIZE Bytes 0-3 of the frame header contain the frame size.] */ /* Codes_SRS_FRAME_CODEC_01_063: [This is an unsigned 32-bit integer that MUST contain the total frame size of the frame header, extended header, and frame body.] */ /* Codes_SRS_FRAME_CODEC_01_064: [The frame is malformed if the size is less than the size of the frame header (8 bytes).] */ unsigned char frame_header[6]; frame_header[0] = (frame_size >> 24) & 0xFF; frame_header[1] = (frame_size >> 16) & 0xFF; frame_header[2] = (frame_size >> 8) & 0xFF; frame_header[3] = frame_size & 0xFF; /* Codes_SRS_FRAME_CODEC_01_065: [DOFF Byte 4 of the frame header is the data offset.] */ frame_header[4] = doff; /* Codes_SRS_FRAME_CODEC_01_069: [TYPE Byte 5 of the frame header is a type code.] */ frame_header[5] = type; /* Codes_SRS_FRAME_CODEC_01_088: [Encoded bytes shall be passed to the on_bytes_encoded callback.] */ on_bytes_encoded(callback_context, frame_header, sizeof(frame_header), ((frame_body_size + type_specific_bytes + padding_byte_count) == 0) ? true : false); /* Codes_SRS_FRAME_CODEC_01_088: [Encoded bytes shall be passed to the on_bytes_encoded callback.] */ if (type_specific_size > 0) { on_bytes_encoded(callback_context, type_specific_bytes, type_specific_size, ((frame_body_size + padding_byte_count) == 0) ? true : false); } /* send padding bytes */ /* Codes_SRS_FRAME_CODEC_01_090: [If the type_specific_size – 2 does not divide by 4, frame_codec_encode_frame shall pad the type_specific bytes with zeroes so that type specific data is according to the AMQP ISO.] */ unsigned char padding_bytes[] = { 0x00, 0x00, 0x00 }; /* Codes_SRS_FRAME_CODEC_01_088: [Encoded bytes shall be passed to the on_bytes_encoded callback.] */ if (padding_byte_count > 0) { on_bytes_encoded(callback_context, padding_bytes, padding_byte_count, (payload_count == 0) ? true : false); } for (i = 0; i < payload_count; i++) { /* Codes_SRS_FRAME_CODEC_01_088: [Encoded bytes shall be passed to the on_bytes_encoded callback.] */ on_bytes_encoded(callback_context, payloads[i].bytes, payloads[i].length, (i == payload_count - 1) ? true : false); } /* Codes_SRS_FRAME_CODEC_01_043: [On success it shall return 0.] */ result = 0; } } return result; }