File content as of revision 27:d74f1cea23e1:

// 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>
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include "azure_c_shared_utility/optimize_size.h"
#include "azure_c_shared_utility/gballoc.h"
#include "azure_c_shared_utility/xlogging.h"
#include "azure_uamqp_c/amqp_frame_codec.h"
#include "azure_uamqp_c/frame_codec.h"
#include "azure_uamqp_c/amqpvalue.h"

typedef enum AMQP_FRAME_DECODE_STATE_TAG
{
	AMQP_FRAME_DECODE_FRAME,
	AMQP_FRAME_DECODE_ERROR
} AMQP_FRAME_DECODE_STATE;

typedef struct AMQP_FRAME_CODEC_INSTANCE_TAG
{
	FRAME_CODEC_HANDLE frame_codec;

	/* decode */
	AMQP_FRAME_RECEIVED_CALLBACK frame_received_callback;
	AMQP_EMPTY_FRAME_RECEIVED_CALLBACK empty_frame_received_callback;
	AMQP_FRAME_CODEC_ERROR_CALLBACK error_callback;
	void* callback_context;
	AMQPVALUE_DECODER_HANDLE decoder;
	AMQP_FRAME_DECODE_STATE decode_state;
	AMQP_VALUE decoded_performative;
} AMQP_FRAME_CODEC_INSTANCE;

static void amqp_value_decoded(void* context, AMQP_VALUE decoded_value)
{
	AMQP_FRAME_CODEC_INSTANCE* amqp_frame_codec_instance = (AMQP_FRAME_CODEC_INSTANCE*)context;
	uint64_t performative_descriptor_ulong;
	AMQP_VALUE descriptor = amqpvalue_get_inplace_descriptor(decoded_value);

	/* Codes_SRS_AMQP_FRAME_CODEC_01_060: [If any error occurs while decoding a frame, the decoder shall switch to an error state where decoding shall not be possible anymore.] */
	if ((descriptor == NULL) ||
		(amqpvalue_get_ulong(descriptor, &performative_descriptor_ulong) != 0) ||
		/* Codes_SRS_AMQP_FRAME_CODEC_01_003: [The performative MUST be one of those defined in section 2.7 and is encoded as a described type in the AMQP type system.] */
		(performative_descriptor_ulong < AMQP_OPEN) ||
		(performative_descriptor_ulong > AMQP_CLOSE))
	{
		/* Codes_SRS_AMQP_FRAME_CODEC_01_060: [If any error occurs while decoding a frame, the decoder shall switch to an error state where decoding shall not be possible anymore.] */
		amqp_frame_codec_instance->decode_state = AMQP_FRAME_DECODE_ERROR;
	}
	else
	{
		amqp_frame_codec_instance->decoded_performative = decoded_value;
	}
}

static void frame_received(void* context, const unsigned char* type_specific, uint32_t type_specific_size, const unsigned char* frame_body, uint32_t frame_body_size)
{
	AMQP_FRAME_CODEC_INSTANCE* amqp_frame_codec_instance = (AMQP_FRAME_CODEC_INSTANCE*)context;
	uint16_t channel;

	switch (amqp_frame_codec_instance->decode_state)
	{
	default:
	/* Codes_SRS_AMQP_FRAME_CODEC_01_050: [All subsequent decoding shall fail and no AMQP frames shall be indicated from that point on to the consumers of amqp_frame_codec.] */
	case AMQP_FRAME_DECODE_ERROR:
		break;

	case AMQP_FRAME_DECODE_FRAME:
		/* Codes_SRS_AMQP_FRAME_CODEC_01_049: [If not enough type specific bytes are received to decode the channel number, the decoding shall stop with an error.] */
		if (type_specific_size < 2)
		{
			amqp_frame_codec_instance->decode_state = AMQP_FRAME_DECODE_ERROR;

			/* Codes_SRS_AMQP_FRAME_CODEC_01_069: [If any error occurs while decoding a frame, the decoder shall indicate the error by calling the amqp_frame_codec_error_callback  and passing to it the callback context argument that was given in amqp_frame_codec_create.] */
			amqp_frame_codec_instance->error_callback(amqp_frame_codec_instance->callback_context);
		}
		else
		{
			/* Codes_SRS_AMQP_FRAME_CODEC_01_001: [Bytes 6 and 7 of an AMQP frame contain the channel number ] */
			channel = ((uint16_t)type_specific[0]) << 8;
			channel += type_specific[1];

			if (frame_body_size == 0)
			{
				/* Codes_SRS_AMQP_FRAME_CODEC_01_048: [When a frame header is received from frame_codec and the frame payload size is 0, empty_frame_received_callback shall be invoked, while passing the channel number as argument.] */
				/* Codes_SRS_AMQP_FRAME_CODEC_01_007: [An AMQP frame with no body MAY be used to generate artificial traffic as needed to satisfy any negotiated idle timeout interval ] */
				amqp_frame_codec_instance->empty_frame_received_callback(amqp_frame_codec_instance->callback_context, channel);
			}
			else
			{
				/* Codes_SRS_AMQP_FRAME_CODEC_01_051: [If the frame payload is greater than 0, amqp_frame_codec shall decode the performative as a described AMQP type.] */
				/* Codes_SRS_AMQP_FRAME_CODEC_01_002: [The frame body is defined as a performative followed by an opaque payload.] */
				amqp_frame_codec_instance->decoded_performative = NULL;

				while ((frame_body_size > 0) &&
					   (amqp_frame_codec_instance->decoded_performative == NULL) &&
					   (amqp_frame_codec_instance->decode_state != AMQP_FRAME_DECODE_ERROR))
				{
					/* Codes_SRS_AMQP_FRAME_CODEC_01_052: [Decoding the performative shall be done by feeding the bytes to the decoder create in amqp_frame_codec_create.] */
					if (amqpvalue_decode_bytes(amqp_frame_codec_instance->decoder, frame_body, 1) != 0)
					{
						/* Codes_SRS_AMQP_FRAME_CODEC_01_060: [If any error occurs while decoding a frame, the decoder shall switch to an error state where decoding shall not be possible anymore.] */
						amqp_frame_codec_instance->decode_state = AMQP_FRAME_DECODE_ERROR;
					}
					else
					{
						frame_body_size--;
						frame_body++;
					}
				}

				if (amqp_frame_codec_instance->decode_state == AMQP_FRAME_DECODE_ERROR)
				{
					/* Codes_SRS_AMQP_FRAME_CODEC_01_069: [If any error occurs while decoding a frame, the decoder shall indicate the error by calling the amqp_frame_codec_error_callback  and passing to it the callback context argument that was given in amqp_frame_codec_create.] */
					amqp_frame_codec_instance->error_callback(amqp_frame_codec_instance->callback_context);
				}
				else
				{
					/* Codes_SRS_AMQP_FRAME_CODEC_01_004: [The remaining bytes in the frame body form the payload for that frame.] */
					/* Codes_SRS_AMQP_FRAME_CODEC_01_067: [When the performative is decoded, the rest of the frame_bytes shall not be given to the AMQP decoder, but they shall be buffered so that later they are given to the frame_received callback.] */
					/* Codes_SRS_AMQP_FRAME_CODEC_01_054: [Once the performative is decoded and all frame payload bytes are received, the callback frame_received_callback shall be called.] */
					/* Codes_SRS_AMQP_FRAME_CODEC_01_068: [A pointer to all the payload bytes shall also be passed to frame_received_callback.] */
					amqp_frame_codec_instance->frame_received_callback(amqp_frame_codec_instance->callback_context, channel, amqp_frame_codec_instance->decoded_performative, frame_body, frame_body_size);
				}
			}
		}
		break;
	}
}

static int encode_bytes(void* context, const unsigned char* bytes, size_t length)
{
	PAYLOAD* payload = (PAYLOAD*)context;
	(void)memcpy((unsigned char*)payload->bytes + payload->length, bytes, length);
	payload->length += length;
	return 0;
}

/* Codes_SRS_AMQP_FRAME_CODEC_01_011: [amqp_frame_codec_create shall create an instance of an amqp_frame_codec and return a non-NULL handle to it.] */
AMQP_FRAME_CODEC_HANDLE amqp_frame_codec_create(FRAME_CODEC_HANDLE frame_codec, AMQP_FRAME_RECEIVED_CALLBACK frame_received_callback,
	AMQP_EMPTY_FRAME_RECEIVED_CALLBACK empty_frame_received_callback, AMQP_FRAME_CODEC_ERROR_CALLBACK amqp_frame_codec_error_callback, void* callback_context)
{
	AMQP_FRAME_CODEC_INSTANCE* result;

	/* Codes_SRS_AMQP_FRAME_CODEC_01_012: [If any of the arguments frame_codec, frame_received_callback, amqp_frame_codec_error_callback or empty_frame_received_callback is NULL, amqp_frame_codec_create shall return NULL.] */
	if ((frame_codec == NULL) ||
		(frame_received_callback == NULL) ||
		(empty_frame_received_callback == NULL) ||
		(amqp_frame_codec_error_callback == NULL))
	{
        LogError("Bad arguments: frame_codec = %p, frame_received_callback = %p, empty_frame_received_callback = %p, amqp_frame_codec_error_callback = %p",
            frame_codec, frame_received_callback, empty_frame_received_callback, amqp_frame_codec_error_callback);
		result = NULL;
	}
	else
	{
		result = (AMQP_FRAME_CODEC_INSTANCE*)malloc(sizeof(AMQP_FRAME_CODEC_INSTANCE));
		/* Codes_SRS_AMQP_FRAME_CODEC_01_020: [If allocating memory for the new amqp_frame_codec fails, then amqp_frame_codec_create shall fail and return NULL.] */
        if (result == NULL)
        {
            LogError("Could not allocate memory for AMQP frame codec");
        }
        else
        {
			result->frame_codec = frame_codec;
			result->frame_received_callback = frame_received_callback;
			result->empty_frame_received_callback = empty_frame_received_callback;
			result->error_callback = amqp_frame_codec_error_callback;
			result->callback_context = callback_context;
			result->decode_state = AMQP_FRAME_DECODE_FRAME;

			/* Codes_SRS_AMQP_FRAME_CODEC_01_018: [amqp_frame_codec_create shall create a decoder to be used for decoding AMQP values.] */
			result->decoder = amqpvalue_decoder_create(amqp_value_decoded, result);
			if (result->decoder == NULL)
			{
				/* Codes_SRS_AMQP_FRAME_CODEC_01_019: [If creating the decoder fails, amqp_frame_codec_create shall fail and return NULL.] */
                LogError("Could not create AMQP decoder");
                free(result);
				result = NULL;
			}
			else
			{
				/* Codes_SRS_AMQP_FRAME_CODEC_01_013: [amqp_frame_codec_create shall subscribe for AMQP frames with the given frame_codec.] */
				if (frame_codec_subscribe(frame_codec, FRAME_TYPE_AMQP, frame_received, result) != 0)
				{
					/* Codes_SRS_AMQP_FRAME_CODEC_01_014: [If subscribing for AMQP frames fails, amqp_frame_codec_create shall fail and return NULL.] */
                    LogError("Could not subscribe for received AMQP frames");
                    amqpvalue_decoder_destroy(result->decoder);
					free(result);
					result = NULL;
				}
			}
		}
	}

	return result;
}

void amqp_frame_codec_destroy(AMQP_FRAME_CODEC_HANDLE amqp_frame_codec)
{
    if (amqp_frame_codec == NULL)
    {
        /* Codes_SRS_AMQP_FRAME_CODEC_01_016: [If amqp_frame_codec is NULL, amqp_frame_codec_destroy shall do nothing.] */
        LogError("NULL amqp_frame_codec");
    }
    else
    {
		/* Codes_SRS_AMQP_FRAME_CODEC_01_017: [amqp_frame_codec_destroy shall unsubscribe from receiving AMQP frames from the frame_codec that was passed to amqp_frame_codec_create.] */
		(void)frame_codec_unsubscribe(amqp_frame_codec->frame_codec, FRAME_TYPE_AMQP);

		/* Codes_SRS_AMQP_FRAME_CODEC_01_021: [The decoder created in amqp_frame_codec_create shall be destroyed by amqp_frame_codec_destroy.] */
		amqpvalue_decoder_destroy(amqp_frame_codec->decoder);

		/* Codes_SRS_AMQP_FRAME_CODEC_01_015: [amqp_frame_codec_destroy shall free all resources associated with the amqp_frame_codec instance.] */
		free(amqp_frame_codec);
	}
}

int amqp_frame_codec_encode_frame(AMQP_FRAME_CODEC_HANDLE amqp_frame_codec, uint16_t channel, const AMQP_VALUE performative, const PAYLOAD* payloads, size_t payload_count, ON_BYTES_ENCODED on_bytes_encoded, void* callback_context)
{
	int result;

	/* Codes_SRS_AMQP_FRAME_CODEC_01_024: [If frame_codec, performative or on_bytes_encoded is NULL, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
	if ((amqp_frame_codec == NULL) ||
		(performative == NULL) ||
		(on_bytes_encoded == NULL))
	{
        LogError("Bad arguments: amqp_frame_codec = %p, performative = %p, on_bytes_encoded = %p",
            amqp_frame_codec, performative, on_bytes_encoded);
        result = __FAILURE__;
	}
	else
	{
		AMQP_VALUE descriptor;
		uint64_t performative_ulong;
		size_t encoded_size;

        if ((descriptor = amqpvalue_get_inplace_descriptor(performative)) == NULL)
        {
            /* Codes_SRS_AMQP_FRAME_CODEC_01_029: [If any error occurs during encoding, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
            LogError("Getting the descriptor failed");
            result = __FAILURE__;
        }
        else if (amqpvalue_get_ulong(descriptor, &performative_ulong) != 0)
        {
            /* Codes_SRS_AMQP_FRAME_CODEC_01_029: [If any error occurs during encoding, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
            LogError("Getting the descriptor ulong failed");
            result = __FAILURE__;
        }
		/* Codes_SRS_AMQP_FRAME_CODEC_01_008: [The performative MUST be one of those defined in section 2.7 and is encoded as a described type in the AMQP type system.] */
        else if ((performative_ulong < AMQP_OPEN) ||
			(performative_ulong > AMQP_CLOSE))
		{
			/* Codes_SRS_AMQP_FRAME_CODEC_01_029: [If any error occurs during encoding, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
            LogError("Bad arguments: amqp_frame_codec = %p, performative = %p, on_bytes_encoded = %p",
                amqp_frame_codec, performative, on_bytes_encoded);
            result = __FAILURE__;
		}
		/* Codes_SRS_AMQP_FRAME_CODEC_01_027: [The encoded size of the performative and its fields shall be obtained by calling amqpvalue_get_encoded_size.] */
		else if (amqpvalue_get_encoded_size(performative, &encoded_size) != 0)
		{
			/* Codes_SRS_AMQP_FRAME_CODEC_01_029: [If any error occurs during encoding, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
            LogError("Getting the encoded size failed");
            result = __FAILURE__;
		}
		else
		{
			unsigned char* amqp_performative_bytes = (unsigned char*)malloc(encoded_size);
			if (amqp_performative_bytes == NULL)
			{
                LogError("Could not allocate performative bytes");
                result = __FAILURE__;
			}
			else
			{
				PAYLOAD* new_payloads = (PAYLOAD*)malloc(sizeof(PAYLOAD) * (payload_count + 1));
				if (new_payloads == NULL)
				{
                    LogError("Could not allocate frame payloads");
                    result = __FAILURE__;
				}
				else
				{
					/* Codes_SRS_AMQP_FRAME_CODEC_01_070: [The payloads argument for frame_codec_encode_frame shall be made of the payload for the encoded performative and the payloads passed to amqp_frame_codec_encode_frame.] */
					/* Codes_SRS_AMQP_FRAME_CODEC_01_028: [The encode result for the performative shall be placed in a PAYLOAD structure.] */
					new_payloads[0].bytes = amqp_performative_bytes;
					new_payloads[0].length = 0;

					if (payload_count > 0)
					{
						(void)memcpy(new_payloads + 1, payloads, sizeof(PAYLOAD) * payload_count);
					}

					if (amqpvalue_encode(performative, encode_bytes, &new_payloads[0]) != 0)
					{
                        LogError("amqpvalue_encode failed");
                        result = __FAILURE__;
					}
					else
					{
                        unsigned char channel_bytes[2];

                        channel_bytes[0] = channel >> 8;
                        channel_bytes[1] = channel & 0xFF;

						/* Codes_SRS_AMQP_FRAME_CODEC_01_005: [Bytes 6 and 7 of an AMQP frame contain the channel number ] */
						/* Codes_SRS_AMQP_FRAME_CODEC_01_025: [amqp_frame_codec_encode_frame shall encode the frame header by using frame_codec_encode_frame.] */
						/* Codes_SRS_AMQP_FRAME_CODEC_01_006: [The frame body is defined as a performative followed by an opaque payload.] */
						if (frame_codec_encode_frame(amqp_frame_codec->frame_codec, FRAME_TYPE_AMQP, new_payloads, payload_count + 1, channel_bytes, sizeof(channel_bytes), on_bytes_encoded, callback_context) != 0)
						{
							/* Codes_SRS_AMQP_FRAME_CODEC_01_029: [If any error occurs during encoding, amqp_frame_codec_encode_frame shall fail and return a non-zero value.] */
                            LogError("frame_codec_encode_frame failed");
                            result = __FAILURE__;
						}
						else
						{
							/* Codes_SRS_AMQP_FRAME_CODEC_01_022: [amqp_frame_codec_begin_encode_frame shall encode the frame header and AMQP performative in an AMQP frame and on success it shall return 0.] */
							result = 0;
						}
					}

					free(new_payloads);
				}

				free(amqp_performative_bytes);
			}
		}
	}

	return result;
}

/* Codes_SRS_AMQP_FRAME_CODEC_01_042: [amqp_frame_codec_encode_empty_frame shall encode a frame with no payload.] */
/* Codes_SRS_AMQP_FRAME_CODEC_01_010: [An AMQP frame with no body MAY be used to generate artificial traffic as needed to satisfy any negotiated idle timeout interval ] */
int amqp_frame_codec_encode_empty_frame(AMQP_FRAME_CODEC_HANDLE amqp_frame_codec, uint16_t channel, ON_BYTES_ENCODED on_bytes_encoded, void* callback_context)
{
	int result;

	/* Codes_SRS_AMQP_FRAME_CODEC_01_045: [If amqp_frame_codec is NULL, amqp_frame_codec_encode_empty_frame shall fail and return a non-zero value.] */
	if (amqp_frame_codec == NULL)
	{
        LogError("NULL amqp_frame_codec");
        result = __FAILURE__;
	}
	else
	{
        unsigned char channel_bytes[2];
        
        channel_bytes[0] = channel >> 8;
        channel_bytes[1] = channel & 0xFF;

		/* Codes_SRS_AMQP_FRAME_CODEC_01_044: [amqp_frame_codec_encode_empty_frame shall use frame_codec_encode_frame to encode the frame.] */
		if (frame_codec_encode_frame(amqp_frame_codec->frame_codec, FRAME_TYPE_AMQP, NULL, 0, channel_bytes, sizeof(channel_bytes), on_bytes_encoded, callback_context) != 0)
		{
			/* Codes_SRS_AMQP_FRAME_CODEC_01_046: [If encoding fails in any way, amqp_frame_codec_encode_empty_frame shall fail and return a non-zero value.]  */
            LogError("frame_codec_encode_frame failed when encoding empty frame");
            result = __FAILURE__;
		}
		else
		{
			/* Codes_SRS_AMQP_FRAME_CODEC_01_043: [On success, amqp_frame_codec_encode_empty_frame shall return 0.] */
			result = 0;
		}
	}

	return result;
}