Add 'CAN-binder/libs/isotp-c/' from commit 'ee24440b7c123ab1b0317e57be33e837a1cb51f1'
authorRomain Forlot <romain.forlot@iot.bzh>
Tue, 2 May 2017 15:51:18 +0000 (17:51 +0200)
committerRomain Forlot <romain.forlot@iot.bzh>
Tue, 2 May 2017 15:51:18 +0000 (17:51 +0200)
git-subtree-dir: CAN-binder/libs/isotp-c
git-subtree-mainline: d170c9faeae2cf29c19f3523714ecdf58be73bed
git-subtree-split: ee24440b7c123ab1b0317e57be33e837a1cb51f1

20 files changed:
1  2 
CAN-binder/libs/isotp-c/.gitignore
CAN-binder/libs/isotp-c/.gitmodules
CAN-binder/libs/isotp-c/.travis.yml
CAN-binder/libs/isotp-c/CHANGELOG.mkd
CAN-binder/libs/isotp-c/LICENSE
CAN-binder/libs/isotp-c/Makefile
CAN-binder/libs/isotp-c/README.mkd
CAN-binder/libs/isotp-c/deps/bitfield-c
CAN-binder/libs/isotp-c/runtests.sh
CAN-binder/libs/isotp-c/src/isotp/isotp.c
CAN-binder/libs/isotp-c/src/isotp/isotp.h
CAN-binder/libs/isotp-c/src/isotp/isotp_types.h
CAN-binder/libs/isotp-c/src/isotp/receive.c
CAN-binder/libs/isotp-c/src/isotp/receive.h
CAN-binder/libs/isotp-c/src/isotp/send.c
CAN-binder/libs/isotp-c/src/isotp/send.h
CAN-binder/libs/isotp-c/tests/common.c
CAN-binder/libs/isotp-c/tests/test_core.c
CAN-binder/libs/isotp-c/tests/test_receive.c
CAN-binder/libs/isotp-c/tests/test_send.c

index 0000000,0000000..96a3694
new file mode 100644 (file)
--- /dev/null
--- /dev/null
@@@ -1,0 -1,0 +1,6 @@@
++*.o
++.DS_Store
++*~
++*.bin
++*.gcno
++build
index 0000000,0000000..aae6d23
new file mode 100644 (file)
--- /dev/null
--- /dev/null
@@@ -1,0 -1,0 +1,3 @@@
++[submodule "deps/canutil"]
++      path = deps/bitfield-c
++      url = https://github.com/openxc/canutil
index 0000000,31bfdeb..31bfdeb
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,8 +1,8 @@@
+ language: c
+ compiler:
+   - gcc
+ script: make test
+ before_install:
+     - git submodule update --init
+     - sudo apt-get update -qq
+     - sudo apt-get install check
index 0000000,e6fd5cc..e6fd5cc
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,10 +1,10 @@@
+ # ISO 15765-2 Support Library in C
+ ## v0.2
+ * Add multi-frame support for diagnostic responses. An IsoTpMessage payload is
+   currently limited to 256 bytes.
+ ## v0.1
+ * Initial release
index 0000000,0000000..330d61f
new file mode 100644 (file)
--- /dev/null
--- /dev/null
@@@ -1,0 -1,0 +1,24 @@@
++Copyright (c) 2013 Ford Motor Company
++All rights reserved.
++
++Redistribution and use in source and binary forms, with or without
++modification, are permitted provided that the following conditions are met:
++    * Redistributions of source code must retain the above copyright
++      notice, this list of conditions and the following disclaimer.
++    * Redistributions in binary form must reproduce the above copyright
++      notice, this list of conditions and the following disclaimer in the
++      documentation and/or other materials provided with the distribution.
++    * Neither the name of the <organization> nor the
++      names of its contributors may be used to endorse or promote products
++      derived from this software without specific prior written permission.
++
++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
++ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
++WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
++DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
++DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
++(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
++LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
++ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
++(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
++SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
index 0000000,90165ba..90165ba
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,56 +1,56 @@@
+ CC = gcc
+ INCLUDES = -Isrc -Ideps/bitfield-c/src
+ CFLAGS = $(INCLUDES) -c -Wall -Werror -g -ggdb -std=gnu99 -coverage
+ LDFLAGS = -coverage
+ LDLIBS = -lcheck -lm -lrt -lpthread
+ TEST_DIR = tests
+ TEST_OBJDIR = build
+ # Guard against \r\n line endings only in Cygwin
+ OSTYPE := $(shell uname)
+ ifneq ($(OSTYPE),Darwin)
+       OSTYPE := $(shell uname -o)
+       ifeq ($(OSTYPE),Cygwin)
+               TEST_SET_OPTS = igncr
+       endif
+ endif
+ LIBS_PATH = deps
+ SRC = $(wildcard src/**/*.c)
+ SRC += $(wildcard deps/bitfield-c/src/**/*.c)
+ OBJS = $(patsubst %,$(TEST_OBJDIR)/%,$(SRC:.c=.o))
+ TEST_SRC = $(wildcard $(TEST_DIR)/test_*.c)
+ TESTS=$(patsubst %.c,$(TEST_OBJDIR)/%.bin,$(TEST_SRC))
+ TEST_SUPPORT_SRC = $(TEST_DIR)/common.c
+ TEST_SUPPORT_OBJS = $(patsubst %,$(TEST_OBJDIR)/%,$(TEST_SUPPORT_SRC:.c=.o))
+ all: $(OBJS)
+ test: $(TESTS)
+       @set -o $(TEST_SET_OPTS) >/dev/null 2>&1
+       @export SHELLOPTS
+       @sh runtests.sh $(TEST_OBJDIR)/$(TEST_DIR)
+ COVERAGE_INFO_FILENAME = coverage.info
+ COVERAGE_INFO_PATH = $(TEST_OBJDIR)/$(COVERAGE_INFO_FILENAME)
+ coverage:
+       @lcov --base-directory . --directory src --zerocounters -q
+       @make clean
+       @make test
+       @lcov --base-directory . --directory $(TEST_OBJDIR) -c -o $(TEST_OBJDIR)/coverage.info
+       @lcov --remove $(COVERAGE_INFO_PATH) "$(LIBS_PATH)/bitfield-c/*" -o $(COVERAGE_INFO_PATH)
+       @genhtml -o $(TEST_OBJDIR)/coverage -t "isotp-c test coverage" --num-spaces 4 $(COVERAGE_INFO_PATH)
+       @$(BROWSER) $(TEST_OBJDIR)/coverage/index.html
+       @echo "$(GREEN)Coverage information generated in $(TEST_OBJDIR)/coverage/index.html.$(COLOR_RESET)"
+ $(TEST_OBJDIR)/%.o: %.c
+       @mkdir -p $(dir $@)
+       $(CC) $(CFLAGS) $(CC_SYMBOLS) $(INCLUDES) -o $@ $<
+ $(TEST_OBJDIR)/%.bin: $(TEST_OBJDIR)/%.o $(OBJS) $(TEST_SUPPORT_OBJS)
+       @mkdir -p $(dir $@)
+       $(CC) $(LDFLAGS) $(CC_SYMBOLS) $(INCLUDES) -o $@ $^ $(LDLIBS)
+ clean:
+       rm -rf $(TEST_OBJDIR)
index 0000000,9803048..9803048
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,142 +1,142 @@@
+ ISO-TP (ISO 15765-2) Support Library in C
+ ================================
+ This is a platform agnostic C library that implements the ISO 15765-2 (also
+ known as ISO-TP) protocol, which runs over a CAN bus. Quoting Wikipedia:
+ >ISO 15765-2, or ISO-TP, is an international standard for sending data packets
+ >over a CAN-Bus. The protocol allows for the transport of messages that exceed
+ >the eight byte maximum payload of CAN frames. ISO-TP segments longer messages
+ >into multiple frames, adding metadata that allows the interpretation of
+ >individual frames and reassembly into a complete message packet by the
+ >recipient. It can carry up to 4095 bytes of payload per message packet.
+ This library doesn't assume anything about the source of the ISO-TP messages or
+ the underlying interface to CAN. It uses dependency injection to give you
+ complete control.
+ The current version supports *only single frame ISO-TP messages*. This is fine
+ for OBD-II diagnostic messages, for example, but this library needs some
+ additional work before it can support sending larger messages.
+ ## Usage
+ First, create some shim functions to let this library use your lower level
+ system:
+     // required, this must send a single CAN message with the given arbitration
+     // ID (i.e. the CAN message ID) and data. The size will never be more than 8
+     // bytes.
+     void send_can(const uint16_t arbitration_id, const uint8_t* data,
+             const uint8_t size) {
+         ...
+     }
+     // optional, provide to receive debugging log messages
+     void debug(const char* format, ...) {
+         ...
+     }
+     // not used in the current version
+     void set_timer(uint16_t time_ms, void (*callback)) {
+         ...
+     }
+ With your shims in place, create an IsoTpShims object to pass them around:
+     IsoTpShims shims = isotp_init_shims(debug, send_can, set_timer);
+ ### API
+ With your shims in hand, send an ISO-TP message:
+     // Optional: This is your callback that will be called when the message is
+     // completely sent. If it was single frame (the only type supported right
+     // now), this will be called immediately.
+     void message_sent(const IsoTpMessage* message, const bool success) {
+         // You received the message! Do something with it.
+     }
+     IsoTpSendHandle handle = isotp_send(&shims, 0x100, NULL, 0, message_sent);
+     if(handle.completed) {
+         if(!handle.success) {
+             // something happened and it already failed - possibly we aren't able to
+             // send CAN messages
+             return;
+         } else {
+             // If the message fit in a single frame, it's already been sent
+             // and you're done
+         }
+     } else {
+         while(true) {
+             // Continue to read from CAN, passing off each message to the handle
+             // this will return true when the message is completely sent (which
+             // may take more than one call if it was multi frame and we're waiting
+             // on flow control responses from the receiver)
+             bool complete = isotp_continue_send(&shims, &handle, 0x100, data, size);
+             if(complete && handle.completed) {
+                 if(handle.success) {
+                     // All frames of the message have now been sent, following
+                     // whatever flow control feedback it got from the receiver
+                 } else {
+                     // the message was unable to be sent and we bailed - fatal
+                     // error!
+                 }
+             }
+         }
+     }
+ Finally, receive an ISO-TP message:
+     // Optional: This is your callback for when a complete ISO-TP message is
+     // received at the arbitration ID you specify. The completed message is
+     // also returned by isotp_continue_receive, which can sometimes be more
+     // useful since you have more context.
+     void message_received(const IsoTpMessage* message) {
+     }
+     IsoTpReceiveHandle handle = isotp_receive(&shims, 0x100, message_received);
+     if(!handle.success) {
+         // something happened and it already failed - possibly we aren't able to
+         // send CAN messages
+     } else {
+         while(true) {
+             // Continue to read from CAN, passing off each message to the handle
+             IsoTpMessage message = isotp_continue_receive(&shims, &handle, 0x100, data, size);
+             if(message.completed && handle.completed) {
+                 if(handle.success) {
+                     // A message has been received successfully
+                 } else {
+                     // Fatal error - we weren't able to receive a message and
+                     // gave up trying. A message using flow control may have
+                     // timed out.
+                 }
+             }
+         }
+     }
+ ## Testing
+ The library includes a test suite that uses the `check` C unit test library.
+     $ make test
+ You can also see the test coverage if you have `lcov` installed and the
+ `BROWSER` environment variable set to your choice of web browsers:
+     $ BROWSER=google-chrome-stable make coverage
+ ## Authors
+ * Chris Peplin cpeplin@ford.com
+ * David Boll dboll2@ford.com (the inspiration for the library's API is from David)
+ ## License
+ Copyright (c) 2013 Ford Motor Company
+ Licensed under the BSD license.
index 0000000,7f1d547..7f1d547
mode 000000,160000..160000
--- /dev/null
@@@ -1,0 -1,1 +1,1 @@@
+ Subproject commit 7f1d5473842361f97fef886bc4e98949ecf853b6
index 0000000,0000000..4781636
new file mode 100644 (file)
--- /dev/null
--- /dev/null
@@@ -1,0 -1,0 +1,17 @@@
++echo "Running unit tests:"
++
++for i in $1/*.bin
++do
++    if test -f $i
++    then
++        if ./$i
++        then
++            echo $i PASS
++        else
++            echo "ERROR in test $i:"
++            exit 1
++        fi
++    fi
++done
++
++echo "${txtbld}$(tput setaf 2)All unit tests passed.$(tput sgr0)"
index 0000000,ce87f1b..ce87f1b
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,32 +1,32 @@@
+ #include <isotp/isotp.h>
+ #include <bitfield/bitfield.h>
+ #include <inttypes.h>
+ /* void isotp_set_timeout(IsoTpHandler* handler, uint16_t timeout_ms) { */
+     /* handler->timeout_ms = timeout_ms; */
+ /* } */
+ IsoTpShims isotp_init_shims(LogShim log, SendCanMessageShim send_can_message,
+         SetTimerShim set_timer) {
+     IsoTpShims shims = {
+         log: log,
+         send_can_message: send_can_message,
+         set_timer: set_timer,
+         frame_padding: ISO_TP_DEFAULT_FRAME_PADDING_STATUS
+     };
+     return shims;
+ }
+ void isotp_message_to_string(const IsoTpMessage* message, char* destination,
+         size_t destination_length) {
+     snprintf(destination, destination_length, "ID: 0x%" SCNd32 ", Payload: 0x%02x%02x%02x%02x%02x%02x%02x%02x",
+             message->arbitration_id,
+             message->payload[0],
+             message->payload[1],
+             message->payload[2],
+             message->payload[3],
+             message->payload[4],
+             message->payload[5],
+             message->payload[6],
+             message->payload[7]);
+ }
index 0000000,3a3658c..3a3658c
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,41 +1,41 @@@
+ #ifndef __ISOTP_H__
+ #define __ISOTP_H__
+ #include <isotp/isotp_types.h>
+ #include <isotp/send.h>
+ #include <isotp/receive.h>
+ #include <stdint.h>
+ #include <stdbool.h>
+ #include <stdio.h>
+ #ifdef __cplusplus
+ extern "C" {
+ #endif
+ /* Public: Initialize an IsoTpShims with the given callback functions.
+  *
+  * If any callbacks are not to be used, set them to NULL. For documentation of
+  * the function type signatures, see isotp_types.h. This struct is a handy
+  * encapsulation used to pass the shims around to the various isotp_* functions.
+  *
+  * Returns a struct with the fields initailized to the callbacks.
+  */
+ IsoTpShims isotp_init_shims(LogShim log,
+         SendCanMessageShim send_can_message,
+         SetTimerShim set_timer);
+ /* Public: Render an IsoTpMessage as a string into the given buffer.
+  *
+  * message - the message to convert to a string, for debug logging.
+  * destination - the target string buffer.
+  * destination_length - the size of the destination buffer, i.e. the max size
+  *      for the rendered string.
+  */
+ void isotp_message_to_string(const IsoTpMessage* message, char* destination,
+         size_t destination_length);
+ #ifdef __cplusplus
+ }
+ #endif
+ #endif // __ISOTP_H__
index 0000000,3b7fd26..3b7fd26
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,144 +1,144 @@@
+ #ifndef __ISOTP_TYPES__
+ #define __ISOTP_TYPES__
+ #include <stdint.h>
+ #include <stdbool.h>
+ #include <stdio.h>
+ #define CAN_MESSAGE_BYTE_SIZE 8
+ #define MAX_ISO_TP_MESSAGE_SIZE 4096
+ // TODO we want to avoid malloc, and we can't be allocated 4K on the stack for
+ // each IsoTpMessage, so for now we're setting an artificial max message size
+ // here - for most multi-frame use cases, 256 bytes is plenty.
+ #define OUR_MAX_ISO_TP_MESSAGE_SIZE 127
+ /* Private: IsoTp nibble specifics for PCI and Payload.
+  */
+ #define PCI_NIBBLE_INDEX 0
+ #define PAYLOAD_LENGTH_NIBBLE_INDEX 1
+ #define PAYLOAD_BYTE_INDEX 1
+ /* Private: The default timeout to use when waiting for a response during a
+  * multi-frame send or receive.
+  */
+ #define ISO_TP_DEFAULT_RESPONSE_TIMEOUT 100
+ /* Private: Determines if by default, padding is added to ISO-TP message frames.
+  */
+ #define ISO_TP_DEFAULT_FRAME_PADDING_STATUS true
+ #ifdef __cplusplus
+ extern "C" {
+ #endif
+ /* Public: A container for a sent or received ISO-TP message.
+  *
+  * completed - An IsoTpMessage is the return value from a few functions - this
+  *      attribute will be true if the message is actually completely received.
+  *      If the function returns but is only partially through receiving the
+  *      message, this will be false, the multi_frame attribute will be true,
+  *      and you should not consider the other data to be valid.
+  * multi_frame - Designates the message is being built with multi-frame.
+  * arbitration_id - The arbitration ID of the message.
+  * payload - The optional payload of the message - don't forget to check the
+  *      size!
+  * size -  The size of the payload. The size will be 0 if there is no payload.
+  */
+ typedef struct {
+     const uint32_t arbitration_id;
+     uint8_t payload[OUR_MAX_ISO_TP_MESSAGE_SIZE];
+     uint16_t size;
+     bool completed;
+     bool multi_frame;
+ } IsoTpMessage;
+ /* Public: The type signature for an optional logging function, if the user
+  * wishes to provide one. It should print, store or otherwise display the
+  * message.
+  *
+  * message - A format string to log using the given parameters.
+  * ... (vargs) - the parameters for the format string.
+  */
+ typedef void (*LogShim)(const char* message, ...);
+ /* Public: The type signature for a function to send a single CAN message.
+  *
+  * arbitration_id - The arbitration ID of the message.
+  * data - The data payload for the message. NULL is valid if size is also 0.
+  * size - The size of the data payload, in bytes.
+  *
+  * Returns true if the CAN message was sent successfully.
+  */
+ typedef bool (*SendCanMessageShim)(const uint32_t arbitration_id,
+         const uint8_t* data, const uint8_t size);
+ /* Public: The type signature for a... TODO, not used yet.
+  */
+ typedef bool (*SetTimerShim)(uint16_t time_ms, void (*callback));
+ /* Public: The signature for a function to be called when an ISO-TP message has
+  * been completely received.
+  *
+  * message - The received message.
+  */
+ typedef void (*IsoTpMessageReceivedHandler)(const IsoTpMessage* message);
+ /* Public: the signature for a function to be called when an ISO-TP message has
+  * been completely sent, or had a fatal error during sending.
+  *
+  * message - The sent message.
+  * success - True if the message was sent successfully.
+  */
+ typedef void (*IsoTpMessageSentHandler)(const IsoTpMessage* message,
+         const bool success);
+ /* Public: The signature for a function to be called when a CAN frame has been
+  * sent as as part of sending or receive an ISO-TP message.
+  *
+  * This is really only useful for debugging the library itself.
+  *
+  * message - The ISO-TP message that generated this CAN frame.
+  */
+ typedef void (*IsoTpCanFrameSentHandler)(const IsoTpMessage* message);
+ /* Public: A container for the 3 shim functions used by the library to interact
+  * with the wider system.
+  *
+  * Use the isotp_init_shims(...) function to create an instance of this struct.
+  *
+  * By default, all CAN frames sent from this device in the process of an ISO-TP
+  * message are padded out to a complete 8 byte frame. This is often required by
+  * ECUs. To disable this feature, change the 'frame_padding' field to false on
+  * the IsoTpShims object returned from isotp_init_shims(...).
+  *
+  * frame_padding - true if outgoing CAN frames should be padded to a full 8
+  *      bytes.
+  */
+ typedef struct {
+     LogShim log;
+     SendCanMessageShim send_can_message;
+     SetTimerShim set_timer;
+     bool frame_padding;
+ } IsoTpShims;
+ /* Private: PCI types, for identifying each frame of an ISO-TP message.
+  */
+ typedef enum {
+     PCI_SINGLE = 0x0,
+     PCI_FIRST_FRAME = 0x1,
+     PCI_CONSECUTIVE_FRAME = 0x2,
+     PCI_FLOW_CONTROL_FRAME = 0x3
+ } IsoTpProtocolControlInformation;
+ /* Private: PCI flow control identifiers.
+  */
+ typedef enum {
+     PCI_FLOW_STATUS_CONTINUE = 0x0,
+     PCI_FLOW_STATUS_WAIT = 0x1,
+     PCI_FLOW_STATUS_OVERFLOW = 0x2
+ } IsoTpFlowStatus;
+ #ifdef __cplusplus
+ }
+ #endif
+ #endif // __ISOTP_TYPES__
index 0000000,35b7a2a..35b7a2a
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,166 +1,166 @@@
+ #include <isotp/receive.h>
+ #include <isotp/send.h>
+ #include <bitfield/bitfield.h>
+ #include <string.h>
+ #include <stdlib.h>
+ #define ARBITRATION_ID_OFFSET 0x8
+ static void isotp_complete_receive(IsoTpReceiveHandle* handle, IsoTpMessage* message) {
+     if(handle->message_received_callback != NULL) {
+         handle->message_received_callback(message);
+     }
+ }
+ bool isotp_handle_single_frame(IsoTpReceiveHandle* handle, IsoTpMessage* message) {
+     isotp_complete_receive(handle, message);
+     return true;
+ }
+ bool isotp_handle_multi_frame(IsoTpReceiveHandle* handle, IsoTpMessage* message) {
+     // call this once all consecutive frames have been received
+     isotp_complete_receive(handle, message);
+     return true;
+ }
+ bool isotp_send_flow_control_frame(IsoTpShims* shims, IsoTpMessage* message) {
+     uint8_t can_data[CAN_MESSAGE_BYTE_SIZE] = {0};
+     if(!set_nibble(PCI_NIBBLE_INDEX, PCI_FLOW_CONTROL_FRAME, can_data, sizeof(can_data))) {
+         shims->log("Unable to set PCI in CAN data");
+         return false;
+     }
+     shims->send_can_message(message->arbitration_id - ARBITRATION_ID_OFFSET, can_data,
+             shims->frame_padding ? 8 : 1 + message->size);
+     return true;
+ }
+ IsoTpReceiveHandle isotp_receive(IsoTpShims* shims,
+         const uint32_t arbitration_id, IsoTpMessageReceivedHandler callback) {
+     IsoTpReceiveHandle handle = {
+         success: false,
+         completed: false,
+         arbitration_id: arbitration_id,
+         message_received_callback: callback
+     };
+     return handle;
+ }
+ IsoTpMessage isotp_continue_receive(IsoTpShims* shims,
+         IsoTpReceiveHandle* handle, const uint32_t arbitration_id,
+         const uint8_t data[], const uint8_t size) {
+     IsoTpMessage message = {
+         arbitration_id: arbitration_id,
+         completed: false,
+         multi_frame: false,
+         payload: {0},
+         size: 0
+     };
+     if(size < 1) {
+         return message;
+     }
+     if(handle->arbitration_id != arbitration_id) {
+         if(shims->log != NULL)  {
+             // You may turn this on for debugging, but in normal operation it's
+             // very noisy if you are passing all received CAN messages to this
+             // handler.
+             /* shims->log("The arb ID 0x%x doesn't match the expected rx ID 0x%x", */
+                     /* arbitration_id, handle->arbitration_id); */
+         }
+         return message;
+     }
+     IsoTpProtocolControlInformation pci = (IsoTpProtocolControlInformation)
+             get_nibble(data, size, 0);
+     // TODO this is set up to handle rx a response with a payload, but not to
+     // handle flow control responses for multi frame messages that we're in the
+     // process of sending
+     switch(pci) {
+         case PCI_SINGLE: {
+             uint8_t payload_length = get_nibble(data, size, 1);
+             
+             if(payload_length > 0) {
+                 memcpy(message.payload, &data[1], payload_length);
+             }
+             
+             message.size = payload_length;
+             message.completed = true;
+             handle->success = true;
+             handle->completed = true;
+             isotp_handle_single_frame(handle, &message);
+             break;
+         }
+         //If multi-frame, then the payload length is contained in the 12
+         //bits following the first nibble of Byte 0. 
+         case PCI_FIRST_FRAME: {
+             uint16_t payload_length = (get_nibble(data, size, 1) << 8) + get_byte(data, size, 1);
+             if(payload_length > OUR_MAX_ISO_TP_MESSAGE_SIZE) {
+                 shims->log("Multi-frame response too large for receive buffer.");
+                 break;
+             }
+             //Need to allocate memory for the combination of multi-frame
+             //messages. That way we don't have to allocate 4k of memory 
+             //for each multi-frame response.
+             uint8_t* combined_payload = NULL;
+             combined_payload = (uint8_t*)malloc(sizeof(uint8_t)*payload_length);
+             if(combined_payload == NULL) {
+                 shims->log("Unable to allocate memory for multi-frame response.");
+                 break;
+             }
+             memcpy(combined_payload, &data[2], CAN_MESSAGE_BYTE_SIZE - 2);
+             handle->receive_buffer = combined_payload;
+             handle->received_buffer_size = CAN_MESSAGE_BYTE_SIZE - 2;
+             handle->incoming_message_size = payload_length;
+             message.multi_frame = true;
+             handle->success = false;
+             handle->completed = false;
+             isotp_send_flow_control_frame(shims, &message);
+             break;
+         }
+         case PCI_CONSECUTIVE_FRAME: {
+             uint8_t start_index = handle->received_buffer_size;
+             uint8_t remaining_bytes = handle->incoming_message_size - start_index;
+             message.multi_frame = true;
+             if(remaining_bytes > 7) {
+                 memcpy(&handle->receive_buffer[start_index], &data[1], CAN_MESSAGE_BYTE_SIZE - 1);
+                 handle->received_buffer_size = start_index + 7;
+             } else {
+                 memcpy(&handle->receive_buffer[start_index], &data[1], remaining_bytes);
+                 handle->received_buffer_size = start_index + remaining_bytes;
+                 if(handle->received_buffer_size != handle->incoming_message_size){
+                     free(handle->receive_buffer);
+                     handle->success = false;
+                     shims->log("Error capturing all bytes of multi-frame. Freeing memory.");
+                 } else {
+                     memcpy(message.payload,&handle->receive_buffer[0],handle->incoming_message_size);
+                     free(handle->receive_buffer);
+                     message.size = handle->incoming_message_size;
+                     message.completed = true;
+                     shims->log("Successfully captured all of multi-frame. Freeing memory.");
+                     handle->success = true;
+                     handle->completed = true;
+                     isotp_handle_multi_frame(handle, &message);
+                 }
+             }
+             break;
+         }
+         default:
+             break;
+     }
+     return message;
+ }
index 0000000,6788914..6788914
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,86 +1,86 @@@
+ #ifndef __ISOTP_RECEIVE_H__
+ #define __ISOTP_RECEIVE_H__
+ #include <isotp/isotp.h>
+ #include <stdint.h>
+ #include <stdbool.h>
+ #ifdef __cplusplus
+ extern "C" {
+ #endif
+ /* Public: A handle for beginning and continuing receiving a single ISO-TP
+  * message - both single and multi-frame.
+  *
+  * Since an ISO-TP message may contain multiple frames, we need to keep a handle
+  * around while waiting for subsequent CAN messages to complete the message.
+  * This struct encapsulates the local state required.
+  *
+  * completed - True if the received message request is completely finished.
+  * success - True if the message request was successful. The value if this field
+  *      isn't valid if 'completed' isn't true.
+  */
+ typedef struct {
+     bool completed;
+     bool success;
+     // Private
+     uint32_t arbitration_id;
+     IsoTpMessageReceivedHandler message_received_callback;
+     uint16_t timeout_ms;
+     // timeout_ms: ISO_TP_DEFAULT_RESPONSE_TIMEOUT,
+     uint8_t* receive_buffer;
+     uint16_t received_buffer_size;
+     uint16_t incoming_message_size;
+     // TODO timer callback for multi frame
+ } IsoTpReceiveHandle;
+ /* Public: Initiate receiving a single ISO-TP message on a particular
+  * arbitration ID.
+  *
+  * Note that no actual CAN data has been received at this point - this just sets
+  * up a handle to be used when new CAN messages to arrive, so they can be parsed
+  * as potential single or multi-frame ISO-TP messages.
+  *
+  * shims -  Low-level shims required to send and receive CAN messages, etc.
+  * arbitration_id - The arbitration ID to receive the message on.
+  * callback - an optional function to be called when the message is completely
+  *      received (use NULL if no callback required).
+  *
+  * Returns a handle to be used with isotp_continue_receive when a new CAN frame
+  * arrives. The 'completed' field in the returned IsoTpReceiveHandle will be true
+  * when the message is completely sent.
+  */
+ IsoTpReceiveHandle isotp_receive(IsoTpShims* shims,
+         const uint32_t arbitration_id, IsoTpMessageReceivedHandler callback);
+ /* Public: Continue to receive a an ISO-TP message, based on a freshly
+  * received CAN message.
+  *
+  * For a multi-frame ISO-TP message, this function must be called
+  * repeatedly whenever a new CAN message is received in order to complete
+  * receipt.
+  *
+  * TODO does this API work for if we wanted to receive an ISO-TP message and
+  * send our own flow control messages back?
+  *
+  * shims -  Low-level shims required to send and receive CAN messages, etc.
+  * handle - An IsoTpReceiveHandle previously returned by isotp_receive(...).
+  * arbitration_id - The arbitration_id of the received CAN message.
+  * data - The data of the received CAN message.
+  * size - The size of the data in the received CAN message.
+  *
+  * Returns an IsoTpMessage with the 'completed' field set to true if a message
+  * was completely received. If 'completed' is false, more CAN frames are
+  * required to complete the messages, or the arbitration ID didn't match this
+  * handle. Keep passing the same handle to this function when CAN frames arrive.
+  */
+ IsoTpMessage isotp_continue_receive(IsoTpShims* shims,
+         IsoTpReceiveHandle* handle, const uint32_t arbitration_id,
+         const uint8_t data[], const uint8_t size);
+ #ifdef __cplusplus
+ }
+ #endif
+ #endif // __ISOTP_RECEIVE_H__
index 0000000,e849bb2..e849bb2
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,89 +1,89 @@@
+ #include <isotp/send.h>
+ #include <bitfield/bitfield.h>
+ #include <string.h>
+ #define PCI_NIBBLE_INDEX 0
+ #define PAYLOAD_LENGTH_NIBBLE_INDEX 1
+ #define PAYLOAD_BYTE_INDEX 1
+ void isotp_complete_send(IsoTpShims* shims, IsoTpMessage* message,
+         bool status, IsoTpMessageSentHandler callback) {
+     if(callback != NULL) {
+         callback(message, status);
+     }
+ }
+ IsoTpSendHandle isotp_send_single_frame(IsoTpShims* shims, IsoTpMessage* message,
+         IsoTpMessageSentHandler callback) {
+     IsoTpSendHandle handle = {
+         success: false,
+         completed: true
+     };
+     uint8_t can_data[CAN_MESSAGE_BYTE_SIZE] = {0};
+     if(!set_nibble(PCI_NIBBLE_INDEX, PCI_SINGLE, can_data, sizeof(can_data))) {
+         shims->log("Unable to set PCI in CAN data");
+         return handle;
+     }
+     if(!set_nibble(PAYLOAD_LENGTH_NIBBLE_INDEX, message->size, can_data,
+                 sizeof(can_data))) {
+         shims->log("Unable to set payload length in CAN data");
+         return handle;
+     }
+     if(message->size > 0) {
+         memcpy(&can_data[1], message->payload, message->size);
+     }
+     shims->send_can_message(message->arbitration_id, can_data,
+             shims->frame_padding ? 8 : 1 + message->size);
+     handle.success = true;
+     isotp_complete_send(shims, message, true, callback);
+     return handle;
+ }
+ IsoTpSendHandle isotp_send_multi_frame(IsoTpShims* shims, IsoTpMessage* message,
+         IsoTpMessageSentHandler callback) {
+     // TODO make sure to copy message into a local buffer
+     shims->log("Only single frame messages are supported");
+     IsoTpSendHandle handle = {
+         success: false,
+         completed: true
+     };
+     // TODO need to set sending and receiving arbitration IDs separately if we
+     // can't always just add 0x8 (and I think we can't)
+     return handle;
+ }
+ IsoTpSendHandle isotp_send(IsoTpShims* shims, const uint16_t arbitration_id,
+         const uint8_t payload[], uint16_t size,
+         IsoTpMessageSentHandler callback) {
+     IsoTpMessage message = {
+         arbitration_id: arbitration_id,
+         size: size
+     };
+     memcpy(message.payload, payload, size);
+     if(size < 8) {
+         return isotp_send_single_frame(shims, &message, callback);
+     } else {
+         return isotp_send_multi_frame(shims, &message, callback);
+     }
+ }
+ bool isotp_continue_send(IsoTpShims* shims, IsoTpSendHandle* handle,
+         const uint16_t arbitration_id, const uint8_t data[],
+         const uint8_t size) {
+     // TODO this will need to be tested when we add multi-frame support,
+     // which is when it'll be necessary to pass in CAN messages to SENDING
+     // handles.
+     if(handle->receiving_arbitration_id != arbitration_id) {
+         if(shims->log != NULL) {
+             shims->log("The arb ID 0x%x doesn't match the expected tx continuation ID 0x%x",
+                     arbitration_id, handle->receiving_arbitration_id);
+         }
+         return false;
+     }
+     return false;
+ }
index 0000000,1af3266..1af3266
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,86 +1,86 @@@
+ #ifndef __ISOTP_SEND_H__
+ #define __ISOTP_SEND_H__
+ #include <isotp/isotp.h>
+ #include <stdint.h>
+ #include <stdbool.h>
+ #ifdef __cplusplus
+ extern "C" {
+ #endif
+ /* Public: A handle for beginning and continuing sending a single ISO-TP
+  * message - both single and multi-frame.
+  *
+  * Since an ISO-TP message may contain multiple frames, we need to keep a handle
+  * around while waiting for flow control messages from the receiver.
+  * This struct encapsulates the local state required.
+  *
+  * completed - True if the message was completely sent, or the send was
+  *      otherwise cancelled.
+  * success - True if the message send request was successful. The value if this
+  *      field isn't valid if 'completed' isn't true.
+  */
+ typedef struct {
+     bool completed;
+     bool success;
+     // Private
+     uint16_t sending_arbitration_id;
+     uint16_t receiving_arbitration_id;
+     IsoTpMessageSentHandler message_sent_callback;
+     IsoTpCanFrameSentHandler can_frame_sent_callback;
+     // TODO going to need some state here for multi frame messages
+ } IsoTpSendHandle;
+ /* Public: Initiate sending a single ISO-TP message.
+  *
+  * If the message fits in a single ISO-TP frame (i.e. the payload isn't more
+  * than 7 bytes) it will be sent immediately and the returned IsoTpSendHandle's
+  * 'completed' flag will be true.
+  *
+  * For multi-frame messages, see isotp_continue_send(...).
+  *
+  * shims -  Low-level shims required to send CAN messages, etc.
+  * arbitration_id - The arbitration ID to send the message on.
+  * payload - The payload for the message. If no payload, NULL is valid is size
+  *      is also 0.
+  * size - The size of the payload, or 0 if no payload.
+  * callback - an optional function to be called when the message is completely
+  *      sent (use NULL if no callback required).
+  *
+  * Returns a handle to be used with isotp_continue_send to continue sending
+  * multi-frame messages. The 'completed' field in the returned IsoTpSendHandle
+  * will be true when the message is completely sent.
+  */
+ IsoTpSendHandle isotp_send(IsoTpShims* shims, const uint16_t arbitration_id,
+         const uint8_t payload[], uint16_t size,
+         IsoTpMessageSentHandler callback);
+ /* Public: Continue to send a multi-frame ISO-TP message, based on a freshly
+  * received CAN message (potentially from the receiver about flow control).
+  *
+  * For a multi-frame ISO-TP message, this function must be called
+  * repeatedly whenever a new CAN message is received in order to complete the
+  * send. The sender can't just blast everything onto the bus at once - it must
+  * wait for some response from the receiver to know how much to send at once.
+  *
+  * shims -  Low-level shims required to send CAN messages, etc.
+  * handle - An IsoTpSendHandle previously returned by isotp_send(...).
+  * arbitration_id - The arbitration_id of the received CAN message.
+  * data - The data of the received CAN message.
+  * size - The size of the data in the received CAN message.
+  *
+  * Returns true if the message was completely sent, or the send was
+  *      otherwise cancelled. Check the 'success' field of the handle to see if
+  *      it was successful.
+  */
+ bool isotp_continue_send(IsoTpShims* shims, IsoTpSendHandle* handle,
+         const uint16_t arbitration_id, const uint8_t data[],
+         const uint8_t size);
+ #ifdef __cplusplus
+ }
+ #endif
+ #endif // __ISOTP_SEND_H__
index 0000000,a9eed39..a9eed39
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,91 +1,91 @@@
+ #include <isotp/isotp.h>
+ #include <stdint.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <stdarg.h>
+ #include <string.h>
+ IsoTpShims SHIMS;
+ IsoTpReceiveHandle RECEIVE_HANDLE;
+ uint32_t last_can_frame_sent_arb_id;
+ uint8_t last_can_payload_sent[8];
+ uint8_t last_can_payload_size;
+ bool can_frame_was_sent;
+ bool message_was_received;
+ uint32_t last_message_received_arb_id;
+ uint8_t last_message_received_payload[OUR_MAX_ISO_TP_MESSAGE_SIZE];
+ uint8_t last_message_received_payload_size;
+ uint32_t last_message_sent_arb_id;
+ bool last_message_sent_status;
+ uint8_t last_message_sent_payload[OUR_MAX_ISO_TP_MESSAGE_SIZE];
+ uint8_t last_message_sent_payload_size;
+ void debug(const char* format, ...) {
+     va_list args;
+     va_start(args, format);
+     vprintf(format, args);
+     printf("\r\n");
+     va_end(args);
+ }
+ bool mock_send_can(const uint32_t arbitration_id, const uint8_t* data,
+         const uint8_t size) {
+     can_frame_was_sent = true;
+     last_can_frame_sent_arb_id = arbitration_id;
+     last_can_payload_size = size;
+     if(size > 0) {
+         memcpy(last_can_payload_sent, data, size);
+     }
+     return true;
+ }
+ void message_received(const IsoTpMessage* message) {
+     debug("Received ISO-TP message:");
+     message_was_received = true;
+     char str_message[48] = {0};
+     isotp_message_to_string(message, str_message, sizeof(str_message));
+     debug("%s", str_message);
+     last_message_received_arb_id = message->arbitration_id;
+     last_message_received_payload_size = message->size;
+     if(message->size > 0) {
+         memcpy(last_message_received_payload, message->payload, message->size);
+     }
+ }
+ void message_sent(const IsoTpMessage* message, const bool success) {
+     if(success) {
+         debug("Sent ISO-TP message:");
+     } else {
+         debug("Unable to send ISO-TP message:");
+     }
+     char str_message[48] = {0};
+     isotp_message_to_string(message, str_message, sizeof(str_message));
+     debug("%s", str_message);
+     last_message_sent_arb_id = message->arbitration_id;
+     last_message_sent_payload_size = message->size;
+     last_message_sent_status = success;
+     if(message->size > 0) {
+         memcpy(last_message_sent_payload, message->payload, message->size);
+     }
+ }
+ void can_frame_sent(const uint32_t arbitration_id, const uint8_t* payload,
+         const uint8_t size) {
+     debug("Sent CAN Frame with arb ID 0x%x and %d bytes", arbitration_id, size);
+ }
+ void setup() {
+     SHIMS = isotp_init_shims(debug, mock_send_can, NULL);
+     RECEIVE_HANDLE = isotp_receive(&SHIMS, 0x2a, message_received);
+     memset(last_message_sent_payload, 0, OUR_MAX_ISO_TP_MESSAGE_SIZE);
+     memset(last_message_received_payload, 0, OUR_MAX_ISO_TP_MESSAGE_SIZE);
+     memset(last_can_payload_sent, 0, sizeof(last_can_payload_sent));
+     last_message_sent_status = false;
+     message_was_received = false;
+     can_frame_was_sent = false;
+ }
index 0000000,73b47af..73b47af
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,78 +1,78 @@@
+ #include <isotp/receive.h>
+ #include <check.h>
+ #include <stdint.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <stdarg.h>
+ extern IsoTpShims SHIMS;
+ extern void message_sent(const IsoTpMessage* message, const bool success);
+ extern uint16_t last_can_frame_sent_arb_id;
+ extern uint8_t last_can_payload_sent[8];
+ extern uint8_t last_can_payload_size;
+ extern bool can_frame_was_sent;
+ extern bool message_was_received;
+ extern uint16_t last_message_received_arb_id;
+ extern uint8_t last_message_received_payload[];
+ extern uint8_t last_message_received_payload_size;
+ extern uint16_t last_message_sent_arb_id;
+ extern bool last_message_sent_status;
+ extern uint8_t last_message_sent_payload[];
+ extern uint8_t last_message_sent_payload_size;
+ extern void setup();
+ START_TEST (test_default_frame_padding_on)
+ {
+     ck_assert(SHIMS.frame_padding);
+     const uint8_t payload[] = {0x12, 0x34};
+     uint32_t arbitration_id = 0x2a;
+     isotp_send(&SHIMS, arbitration_id, payload, sizeof(payload), message_sent);
+     ck_assert_int_eq(last_message_sent_arb_id, arbitration_id);
+     fail_unless(last_message_sent_status);
+     ck_assert_int_eq(last_message_sent_payload_size, 2);
+     ck_assert_int_eq(last_can_payload_size, 8);
+ }
+ END_TEST
+ START_TEST (test_disabled_frame_padding)
+ {
+     SHIMS.frame_padding = false;
+     const uint8_t payload[] = {0x12, 0x34};
+     uint32_t arbitration_id = 0x2a;
+     isotp_send(&SHIMS, arbitration_id, payload, sizeof(payload), message_sent);
+     ck_assert_int_eq(last_message_sent_arb_id, arbitration_id);
+     fail_unless(last_message_sent_status);
+     ck_assert_int_eq(last_message_sent_payload_size, 2);
+     ck_assert_int_eq(last_can_payload_size, 3);
+ }
+ END_TEST
+ Suite* testSuite(void) {
+     Suite* s = suite_create("iso15765");
+     TCase *tc_core = tcase_create("core");
+     tcase_add_checked_fixture(tc_core, setup, NULL);
+     tcase_add_test(tc_core, test_default_frame_padding_on);
+     tcase_add_test(tc_core, test_disabled_frame_padding);
+     suite_add_tcase(s, tc_core);
+     return s;
+ }
+ int main(void) {
+     int numberFailed;
+     Suite* s = testSuite();
+     SRunner *sr = srunner_create(s);
+     // Don't fork so we can actually use gdb
+     srunner_set_fork_status(sr, CK_NOFORK);
+     srunner_run_all(sr, CK_NORMAL);
+     numberFailed = srunner_ntests_failed(sr);
+     srunner_free(sr);
+     return (numberFailed == 0) ? 0 : 1;
+ }
index 0000000,607f906..607f906
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,176 +1,176 @@@
+ #include <isotp/isotp.h>
+ #include <check.h>
+ #include <stdint.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <stdarg.h>
+ extern IsoTpShims SHIMS;
+ extern IsoTpReceiveHandle RECEIVE_HANDLE;
+ extern void message_sent(const IsoTpMessage* message, const bool success);
+ extern uint16_t last_can_frame_sent_arb_id;
+ extern uint8_t last_can_payload_sent;
+ extern uint8_t last_can_payload_size;
+ extern bool can_frame_was_sent;
+ extern bool message_was_received;
+ extern uint16_t last_message_received_arb_id;
+ extern uint8_t last_message_received_payload[];
+ extern uint8_t last_message_received_payload_size;
+ extern uint16_t last_message_sent_arb_id;
+ extern bool last_message_sent_status;
+ extern uint8_t last_message_sent_payload[];
+ extern uint8_t last_message_sent_payload_size;
+ extern void setup();
+ START_TEST (test_receive_empty_can_message)
+ {
+     const uint8_t data[CAN_MESSAGE_BYTE_SIZE] = {0};
+     fail_if(RECEIVE_HANDLE.completed);
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x100, data, 0);
+     fail_if(message.completed);
+     fail_if(message_was_received);
+ }
+ END_TEST
+ START_TEST (test_receive_wrong_id)
+ {
+     const uint8_t data[CAN_MESSAGE_BYTE_SIZE] = {0};
+     fail_if(RECEIVE_HANDLE.completed);
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x100, data, 1);
+     fail_if(message.completed);
+     fail_if(message_was_received);
+ }
+ END_TEST
+ START_TEST (test_receive_bad_pci)
+ {
+     // 4 is a reserved number for the PCI field - only 0-3 are allowed
+     const uint8_t data[CAN_MESSAGE_BYTE_SIZE] = {0x40};
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data, 1);
+     fail_if(message.completed);
+     fail_if(message_was_received);
+ }
+ END_TEST
+ START_TEST (test_receive_single_frame_empty_payload)
+ {
+     const uint8_t data[CAN_MESSAGE_BYTE_SIZE] = {0x00, 0x12, 0x34};
+     fail_if(RECEIVE_HANDLE.completed);
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data, 3);
+     fail_unless(RECEIVE_HANDLE.completed);
+     fail_unless(message.completed);
+     fail_unless(message_was_received);
+     ck_assert_int_eq(last_message_received_arb_id, 0x2a);
+     ck_assert_int_eq(last_message_received_payload_size, 0);
+ }
+ END_TEST
+ START_TEST (test_receive_single_frame)
+ {
+     const uint8_t data[CAN_MESSAGE_BYTE_SIZE] = {0x02, 0x12, 0x34};
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data, 3);
+     fail_unless(message.completed);
+     fail_unless(message_was_received);
+     ck_assert_int_eq(last_message_received_arb_id, 0x2a);
+     ck_assert_int_eq(last_message_received_payload_size, 2);
+     ck_assert_int_eq(last_message_received_payload[0], 0x12);
+     ck_assert_int_eq(last_message_received_payload[1], 0x34);
+ }
+ END_TEST
+ START_TEST (test_receive_multi_frame)
+ {
+     const uint8_t data0[CAN_MESSAGE_BYTE_SIZE] = {0x10, 0x14, 0x49, 0x02, 0x01, 0x31, 0x46, 0x4d};
+     IsoTpMessage message0 = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data0, 8);
+     fail_unless(!RECEIVE_HANDLE.completed);
+     fail_unless(!message0.completed);
+     fail_unless(!message_was_received);
+     fail_unless(message0.multi_frame);
+     //make sure flow control message has been sent.
+     ck_assert_int_eq(last_can_frame_sent_arb_id, 0x2a - 8);
+     ck_assert_int_eq(last_can_payload_sent, 0x30);
+     const uint8_t data1[CAN_MESSAGE_BYTE_SIZE] = {0x21, 0x43, 0x55, 0x39, 0x4a, 0x39, 0x34, 0x48};
+     IsoTpMessage message1 = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data1, 8);
+     fail_unless(!RECEIVE_HANDLE.completed);
+     fail_unless(!message1.completed);
+     fail_unless(!message_was_received);
+     fail_unless(message1.multi_frame);
+     const uint8_t data2[CAN_MESSAGE_BYTE_SIZE] = {0x22, 0x55, 0x41, 0x30, 0x34, 0x35, 0x32, 0x34};
+     IsoTpMessage message2 = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data2, 8);
+     fail_unless(RECEIVE_HANDLE.completed);
+     fail_unless(message2.completed);
+     fail_unless(message_was_received);
+     fail_unless(message2.multi_frame);
+     ck_assert_int_eq(last_message_received_arb_id, 0x2a);
+     ck_assert_int_eq(last_message_received_payload_size, 0x14);
+     ck_assert_int_eq(last_message_received_payload[0], 0x49);
+     ck_assert_int_eq(last_message_received_payload[1], 0x02);
+     ck_assert_int_eq(last_message_received_payload[2], 0x01);
+     ck_assert_int_eq(last_message_received_payload[3], 0x31);
+     ck_assert_int_eq(last_message_received_payload[4], 0x46);
+     ck_assert_int_eq(last_message_received_payload[5], 0x4d);
+     ck_assert_int_eq(last_message_received_payload[6], 0x43);
+     ck_assert_int_eq(last_message_received_payload[7], 0x55);
+     ck_assert_int_eq(last_message_received_payload[8], 0x39);
+     ck_assert_int_eq(last_message_received_payload[9], 0x4a);
+     ck_assert_int_eq(last_message_received_payload[10], 0x39);
+     ck_assert_int_eq(last_message_received_payload[11], 0x34);
+     ck_assert_int_eq(last_message_received_payload[12], 0x48);
+     ck_assert_int_eq(last_message_received_payload[13], 0x55);
+     ck_assert_int_eq(last_message_received_payload[14], 0x41);
+     ck_assert_int_eq(last_message_received_payload[15], 0x30);
+     ck_assert_int_eq(last_message_received_payload[16], 0x34);
+     ck_assert_int_eq(last_message_received_payload[17], 0x35);
+     ck_assert_int_eq(last_message_received_payload[18], 0x32);
+     ck_assert_int_eq(last_message_received_payload[19], 0x34);
+ }
+ END_TEST
+ START_TEST (test_receive_large_multi_frame)
+ {
+     const uint8_t data0[CAN_MESSAGE_BYTE_SIZE] = {0x10, 0x80, 0x49, 0x02, 0x01, 0x31, 0x46, 0x4d};
+     IsoTpMessage message = isotp_continue_receive(&SHIMS, &RECEIVE_HANDLE, 0x2a, data0, 8);
+     //Make sure we don't try to receive messages that are too large and don't send flow control.
+     fail_unless(!can_frame_was_sent);
+     fail_unless(!RECEIVE_HANDLE.completed);
+     fail_unless(!message.completed);
+     fail_unless(!message_was_received);
+     fail_unless(!message.multi_frame);
+ }
+ END_TEST
+ Suite* testSuite(void) {
+     Suite* s = suite_create("iso15765");
+     TCase *tc_core = tcase_create("receive");
+     tcase_add_checked_fixture(tc_core, setup, NULL);
+     tcase_add_test(tc_core, test_receive_wrong_id);
+     tcase_add_test(tc_core, test_receive_bad_pci);
+     tcase_add_test(tc_core, test_receive_single_frame);
+     tcase_add_test(tc_core, test_receive_single_frame_empty_payload);
+     tcase_add_test(tc_core, test_receive_empty_can_message);
+     tcase_add_test(tc_core, test_receive_multi_frame);
+     tcase_add_test(tc_core, test_receive_large_multi_frame);
+     suite_add_tcase(s, tc_core);
+     return s;
+ }
+ int main(void) {
+     int numberFailed;
+     Suite* s = testSuite();
+     SRunner *sr = srunner_create(s);
+     // Don't fork so we can actually use gdb
+     srunner_set_fork_status(sr, CK_NOFORK);
+     srunner_run_all(sr, CK_NORMAL);
+     numberFailed = srunner_ntests_failed(sr);
+     srunner_free(sr);
+     return (numberFailed == 0) ? 0 : 1;
+ }
index 0000000,29cf5de..29cf5de
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,103 +1,103 @@@
+ #include <isotp/receive.h>
+ #include <check.h>
+ #include <stdint.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <stdarg.h>
+ extern IsoTpShims SHIMS;
+ extern void message_sent(const IsoTpMessage* message, const bool success);
+ extern uint16_t last_can_frame_sent_arb_id;
+ extern uint8_t last_can_payload_sent[8];
+ extern uint8_t last_can_payload_size;
+ extern bool can_frame_was_sent;
+ extern bool message_was_received;
+ extern uint16_t last_message_received_arb_id;
+ extern uint8_t last_message_received_payload[];
+ extern uint8_t last_message_received_payload_size;
+ extern uint16_t last_message_sent_arb_id;
+ extern bool last_message_sent_status;
+ extern uint8_t last_message_sent_payload[];
+ extern uint8_t last_message_sent_payload_size;
+ extern void setup();
+ START_TEST (test_send_empty_payload)
+ {
+     SHIMS.frame_padding = false;
+     uint16_t arbitration_id = 0x2a;
+     IsoTpSendHandle handle = isotp_send(&SHIMS, arbitration_id, NULL, 0, message_sent);
+     fail_unless(handle.success);
+     fail_unless(handle.completed);
+     ck_assert_int_eq(last_message_sent_arb_id, arbitration_id);
+     fail_unless(last_message_sent_status);
+     ck_assert_int_eq(last_message_sent_payload[0], '\0');
+     ck_assert_int_eq(last_message_sent_payload_size, 0);
+     ck_assert_int_eq(last_can_frame_sent_arb_id, arbitration_id);
+     fail_unless(can_frame_was_sent);
+     ck_assert_int_eq(last_can_payload_sent[0], 0x0);
+     ck_assert_int_eq(last_can_payload_size, 1);
+ }
+ END_TEST
+ START_TEST (test_send_single_frame)
+ {
+     SHIMS.frame_padding = false;
+     const uint8_t payload[] = {0x12, 0x34};
+     uint16_t arbitration_id = 0x2a;
+     isotp_send(&SHIMS, arbitration_id, payload, sizeof(payload), message_sent);
+     ck_assert_int_eq(last_message_sent_arb_id, arbitration_id);
+     fail_unless(last_message_sent_status);
+     ck_assert_int_eq(last_message_sent_payload[0], 0x12);
+     ck_assert_int_eq(last_message_sent_payload[1], 0x34);
+     ck_assert_int_eq(last_message_sent_payload_size, 2);
+     ck_assert_int_eq(last_can_frame_sent_arb_id, arbitration_id);
+     fail_unless(can_frame_was_sent);
+     ck_assert_int_eq(last_can_payload_sent[0], 0x2);
+     ck_assert_int_eq(last_can_payload_sent[1], 0x12);
+     ck_assert_int_eq(last_can_payload_sent[2], 0x34);
+     ck_assert_int_eq(last_can_payload_size, 3);
+ }
+ END_TEST
+ START_TEST (test_send_multi_frame)
+ {
+     const uint8_t payload[] = {0x12, 0x34, 0x56, 0x78, 0x90, 0x01, 0x23,
+             0x45, 0x67, 0x89};
+     uint16_t arbitration_id = 0x2a;
+     IsoTpSendHandle handle = isotp_send(&SHIMS, arbitration_id, payload, sizeof(payload),
+             message_sent);
+     fail_unless(handle.completed);
+     fail_if(handle.success);
+ }
+ END_TEST
+ Suite* testSuite(void) {
+     Suite* s = suite_create("iso15765");
+     TCase *tc_core = tcase_create("send");
+     tcase_add_checked_fixture(tc_core, setup, NULL);
+     tcase_add_test(tc_core, test_send_empty_payload);
+     tcase_add_test(tc_core, test_send_single_frame);
+     tcase_add_test(tc_core, test_send_multi_frame);
+     suite_add_tcase(s, tc_core);
+     return s;
+ }
+ int main(void) {
+     int numberFailed;
+     Suite* s = testSuite();
+     SRunner *sr = srunner_create(s);
+     // Don't fork so we can actually use gdb
+     srunner_set_fork_status(sr, CK_NOFORK);
+     srunner_run_all(sr, CK_NORMAL);
+     numberFailed = srunner_ntests_failed(sr);
+     srunner_free(sr);
+     return (numberFailed == 0) ? 0 : 1;
+ }