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diff --git a/tinyusb/test/vendor/ceedling/docs/UnityConfigurationGuide.md b/tinyusb/test/vendor/ceedling/docs/UnityConfigurationGuide.md new file mode 100755 index 00000000..dace20c5 --- /dev/null +++ b/tinyusb/test/vendor/ceedling/docs/UnityConfigurationGuide.md @@ -0,0 +1,433 @@ +# Unity Configuration Guide + +## C Standards, Compilers and Microcontrollers + +The embedded software world contains its challenges. Compilers support different +revisions of the C Standard. They ignore requirements in places, sometimes to +make the language more usable in some special regard. Sometimes it's to simplify +their support. Sometimes it's due to specific quirks of the microcontroller they +are targeting. Simulators add another dimension to this menagerie. + +Unity is designed to run on almost anything that is targeted by a C compiler. It +would be awesome if this could be done with zero configuration. While there are +some targets that come close to this dream, it is sadly not universal. It is +likely that you are going to need at least a couple of the configuration options +described in this document. + +All of Unity's configuration options are `#defines`. Most of these are simple +definitions. A couple are macros with arguments. They live inside the +unity_internals.h header file. We don't necessarily recommend opening that file +unless you really need to. That file is proof that a cross-platform library is +challenging to build. From a more positive perspective, it is also proof that a +great deal of complexity can be centralized primarily to one place to +provide a more consistent and simple experience elsewhere. + + +### Using These Options + +It doesn't matter if you're using a target-specific compiler and a simulator or +a native compiler. In either case, you've got a couple choices for configuring +these options: + +1. Because these options are specified via C defines, you can pass most of these +options to your compiler through command line compiler flags. Even if you're +using an embedded target that forces you to use their overbearing IDE for all +configuration, there will be a place somewhere in your project to configure +defines for your compiler. +2. You can create a custom `unity_config.h` configuration file (present in your +toolchain's search paths). In this file, you will list definitions and macros +specific to your target. All you must do is define `UNITY_INCLUDE_CONFIG_H` and +Unity will rely on `unity_config.h` for any further definitions it may need. + + +## The Options + +### Integer Types + +If you've been a C developer for long, you probably already know that C's +concept of an integer varies from target to target. The C Standard has rules +about the `int` matching the register size of the target microprocessor. It has +rules about the `int` and how its size relates to other integer types. An `int` +on one target might be 16 bits while on another target it might be 64. There are +more specific types in compilers compliant with C99 or later, but that's +certainly not every compiler you are likely to encounter. Therefore, Unity has a +number of features for helping to adjust itself to match your required integer +sizes. It starts off by trying to do it automatically. + + +##### `UNITY_EXCLUDE_STDINT_H` + +The first thing that Unity does to guess your types is check `stdint.h`. +This file includes defines like `UINT_MAX` that Unity can use to +learn a lot about your system. It's possible you don't want it to do this +(um. why not?) or (more likely) it's possible that your system doesn't +support `stdint.h`. If that's the case, you're going to want to define this. +That way, Unity will know to skip the inclusion of this file and you won't +be left with a compiler error. + +_Example:_ + #define UNITY_EXCLUDE_STDINT_H + + +##### `UNITY_EXCLUDE_LIMITS_H` + +The second attempt to guess your types is to check `limits.h`. Some compilers +that don't support `stdint.h` could include `limits.h` instead. If you don't +want Unity to check this file either, define this to make it skip the inclusion. + +_Example:_ + #define UNITY_EXCLUDE_LIMITS_H + + +If you've disabled both of the automatic options above, you're going to have to +do the configuration yourself. Don't worry. Even this isn't too bad... there are +just a handful of defines that you are going to specify if you don't like the +defaults. + + +##### `UNITY_INT_WIDTH` + +Define this to be the number of bits an `int` takes up on your system. The +default, if not autodetected, is 32 bits. + +_Example:_ + #define UNITY_INT_WIDTH 16 + + +##### `UNITY_LONG_WIDTH` + +Define this to be the number of bits a `long` takes up on your system. The +default, if not autodetected, is 32 bits. This is used to figure out what kind +of 64-bit support your system can handle. Does it need to specify a `long` or a +`long long` to get a 64-bit value. On 16-bit systems, this option is going to be +ignored. + +_Example:_ + #define UNITY_LONG_WIDTH 16 + + +##### `UNITY_POINTER_WIDTH` + +Define this to be the number of bits a pointer takes up on your system. The +default, if not autodetected, is 32-bits. If you're getting ugly compiler +warnings about casting from pointers, this is the one to look at. + +_Example:_ + #define UNITY_POINTER_WIDTH 64 + + +##### `UNITY_SUPPORT_64` + +Unity will automatically include 64-bit support if it auto-detects it, or if +your `int`, `long`, or pointer widths are greater than 32-bits. Define this to +enable 64-bit support if none of the other options already did it for you. There +can be a significant size and speed impact to enabling 64-bit support on small +targets, so don't define it if you don't need it. + +_Example:_ + #define UNITY_SUPPORT_64 + + +### Floating Point Types + +In the embedded world, it's not uncommon for targets to have no support for +floating point operations at all or to have support that is limited to only +single precision. We are able to guess integer sizes on the fly because integers +are always available in at least one size. Floating point, on the other hand, is +sometimes not available at all. Trying to include `float.h` on these platforms +would result in an error. This leaves manual configuration as the only option. + + +##### `UNITY_INCLUDE_FLOAT` + +##### `UNITY_EXCLUDE_FLOAT` + +##### `UNITY_INCLUDE_DOUBLE` + +##### `UNITY_EXCLUDE_DOUBLE` + +By default, Unity guesses that you will want single precision floating point +support, but not double precision. It's easy to change either of these using the +include and exclude options here. You may include neither, either, or both, as +suits your needs. For features that are enabled, the following floating point +options also become available. + +_Example:_ + + //what manner of strange processor is this? + #define UNITY_EXCLUDE_FLOAT + #define UNITY_INCLUDE_DOUBLE + + +##### `UNITY_EXCLUDE_FLOAT_PRINT` + +Unity aims for as small of a footprint as possible and avoids most standard +library calls (some embedded platforms don’t have a standard library!). Because +of this, its routines for printing integer values are minimalist and hand-coded. +Therefore, the display of floating point values during a failure are optional. +By default, Unity will print the actual results of floating point assertion +failure (e.g. ”Expected 4.56 Was 4.68”). To not include this extra support, you +can use this define to instead respond to a failed assertion with a message like +”Values Not Within Delta”. If you would like verbose failure messages for floating +point assertions, use these options to give more explicit failure messages. + +_Example:_ + #define UNITY_EXCLUDE_FLOAT_PRINT + + +##### `UNITY_FLOAT_TYPE` + +If enabled, Unity assumes you want your `FLOAT` asserts to compare standard C +floats. If your compiler supports a specialty floating point type, you can +always override this behavior by using this definition. + +_Example:_ + #define UNITY_FLOAT_TYPE float16_t + + +##### `UNITY_DOUBLE_TYPE` + +If enabled, Unity assumes you want your `DOUBLE` asserts to compare standard C +doubles. If you would like to change this, you can specify something else by +using this option. For example, defining `UNITY_DOUBLE_TYPE` to `long double` +could enable gargantuan floating point types on your 64-bit processor instead of +the standard `double`. + +_Example:_ + #define UNITY_DOUBLE_TYPE long double + + +##### `UNITY_FLOAT_PRECISION` + +##### `UNITY_DOUBLE_PRECISION` + +If you look up `UNITY_ASSERT_EQUAL_FLOAT` and `UNITY_ASSERT_EQUAL_DOUBLE` as +documented in the big daddy Unity Assertion Guide, you will learn that they are +not really asserting that two values are equal but rather that two values are +"close enough" to equal. "Close enough" is controlled by these precision +configuration options. If you are working with 32-bit floats and/or 64-bit +doubles (the normal on most processors), you should have no need to change these +options. They are both set to give you approximately 1 significant bit in either +direction. The float precision is 0.00001 while the double is 10-12. +For further details on how this works, see the appendix of the Unity Assertion +Guide. + +_Example:_ + #define UNITY_FLOAT_PRECISION 0.001f + + +### Toolset Customization + +In addition to the options listed above, there are a number of other options +which will come in handy to customize Unity's behavior for your specific +toolchain. It is possible that you may not need to touch any of these... but +certain platforms, particularly those running in simulators, may need to jump +through extra hoops to run properly. These macros will help in those +situations. + + +##### `UNITY_OUTPUT_CHAR(a)` + +##### `UNITY_OUTPUT_FLUSH()` + +##### `UNITY_OUTPUT_START()` + +##### `UNITY_OUTPUT_COMPLETE()` + +By default, Unity prints its results to `stdout` as it runs. This works +perfectly fine in most situations where you are using a native compiler for +testing. It works on some simulators as well so long as they have `stdout` +routed back to the command line. There are times, however, where the simulator +will lack support for dumping results or you will want to route results +elsewhere for other reasons. In these cases, you should define the +`UNITY_OUTPUT_CHAR` macro. This macro accepts a single character at a time (as +an `int`, since this is the parameter type of the standard C `putchar` function +most commonly used). You may replace this with whatever function call you like. + +_Example:_ +Say you are forced to run your test suite on an embedded processor with no +`stdout` option. You decide to route your test result output to a custom serial +`RS232_putc()` function you wrote like thus: + #include "RS232_header.h" + ... + #define UNITY_OUTPUT_CHAR(a) RS232_putc(a) + #define UNITY_OUTPUT_START() RS232_config(115200,1,8,0) + #define UNITY_OUTPUT_FLUSH() RS232_flush() + #define UNITY_OUTPUT_COMPLETE() RS232_close() + +_Note:_ +`UNITY_OUTPUT_FLUSH()` can be set to the standard out flush function simply by +specifying `UNITY_USE_FLUSH_STDOUT`. No other defines are required. + + +##### `UNITY_WEAK_ATTRIBUTE` + +##### `UNITY_WEAK_PRAGMA` + +##### `UNITY_NO_WEAK` + +For some targets, Unity can make the otherwise required setUp() and tearDown() +functions optional. This is a nice convenience for test writers since setUp and +tearDown don’t often actually do anything. If you’re using gcc or clang, this +option is automatically defined for you. Other compilers can also support this +behavior, if they support a C feature called weak functions. A weak function is +a function that is compiled into your executable unless a non-weak version of +the same function is defined elsewhere. If a non-weak version is found, the weak +version is ignored as if it never existed. If your compiler supports this feature, +you can let Unity know by defining UNITY_WEAK_ATTRIBUTE or UNITY_WEAK_PRAGMA as +the function attributes that would need to be applied to identify a function as +weak. If your compiler lacks support for weak functions, you will always need to +define setUp and tearDown functions (though they can be and often will be just +empty). You can also force Unity to NOT use weak functions by defining +UNITY_NO_WEAK. The most common options for this feature are: + +_Example:_ + #define UNITY_WEAK_ATTRIBUTE weak + #define UNITY_WEAK_ATTRIBUTE __attribute__((weak)) + #define UNITY_WEAK_PRAGMA + #define UNITY_NO_WEAK + + +##### `UNITY_PTR_ATTRIBUTE` + +Some compilers require a custom attribute to be assigned to pointers, like +`near` or `far`. In these cases, you can give Unity a safe default for these by +defining this option with the attribute you would like. + +_Example:_ + #define UNITY_PTR_ATTRIBUTE __attribute__((far)) + #define UNITY_PTR_ATTRIBUTE near + + +##### `UNITY_PRINT_EOL` + +By default, Unity outputs \n at the end of each line of output. This is easy +to parse by the scripts, by Ceedling, etc, but it might not be ideal for YOUR +system. Feel free to override this and to make it whatever you wish. + +_Example:_ + #define UNITY_PRINT_EOL { UNITY_OUTPUT_CHAR('\r'); UNITY_OUTPUT_CHAR('\n') } + + + +##### `UNITY_EXCLUDE_DETAILS` + +This is an option for if you absolutely must squeeze every byte of memory out of +your system. Unity stores a set of internal scratchpads which are used to pass +extra detail information around. It's used by systems like CMock in order to +report which function or argument flagged an error. If you're not using CMock and +you're not using these details for other things, then you can exclude them. + +_Example:_ + #define UNITY_EXCLUDE_DETAILS + + + +##### `UNITY_EXCLUDE_SETJMP` + +If your embedded system doesn't support the standard library setjmp, you can +exclude Unity's reliance on this by using this define. This dropped dependence +comes at a price, though. You will be unable to use custom helper functions for +your tests, and you will be unable to use tools like CMock. Very likely, if your +compiler doesn't support setjmp, you wouldn't have had the memory space for those +things anyway, though... so this option exists for those situations. + +_Example:_ + #define UNITY_EXCLUDE_SETJMP + +##### `UNITY_OUTPUT_COLOR` + +If you want to add color using ANSI escape codes you can use this define. +t +_Example:_ + #define UNITY_OUTPUT_COLOR + + + +## Getting Into The Guts + +There will be cases where the options above aren't quite going to get everything +perfect. They are likely sufficient for any situation where you are compiling +and executing your tests with a native toolchain (e.g. clang on Mac). These +options may even get you through the majority of cases encountered in working +with a target simulator run from your local command line. But especially if you +must run your test suite on your target hardware, your Unity configuration will +require special help. This special help will usually reside in one of two +places: the `main()` function or the `RUN_TEST` macro. Let's look at how these +work. + + +##### `main()` + +Each test module is compiled and run on its own, separate from the other test +files in your project. Each test file, therefore, has a `main` function. This +`main` function will need to contain whatever code is necessary to initialize +your system to a workable state. This is particularly true for situations where +you must set up a memory map or initialize a communication channel for the +output of your test results. + +A simple main function looks something like this: + + int main(void) { + UNITY_BEGIN(); + RUN_TEST(test_TheFirst); + RUN_TEST(test_TheSecond); + RUN_TEST(test_TheThird); + return UNITY_END(); + } + +You can see that our main function doesn't bother taking any arguments. For our +most barebones case, we'll never have arguments because we just run all the +tests each time. Instead, we start by calling `UNITY_BEGIN`. We run each test +(in whatever order we wish). Finally, we call `UNITY_END`, returning its return +value (which is the total number of failures). + +It should be easy to see that you can add code before any test cases are run or +after all the test cases have completed. This allows you to do any needed +system-wide setup or teardown that might be required for your special +circumstances. + + +##### `RUN_TEST` + +The `RUN_TEST` macro is called with each test case function. Its job is to +perform whatever setup and teardown is necessary for executing a single test +case function. This includes catching failures, calling the test module's +`setUp()` and `tearDown()` functions, and calling `UnityConcludeTest()`. If +using CMock or test coverage, there will be additional stubs in use here. A +simple minimalist RUN_TEST macro looks something like this: + + #define RUN_TEST(testfunc) \ + UNITY_NEW_TEST(#testfunc) \ + if (TEST_PROTECT()) { \ + setUp(); \ + testfunc(); \ + } \ + if (TEST_PROTECT() && (!TEST_IS_IGNORED)) \ + tearDown(); \ + UnityConcludeTest(); + +So that's quite a macro, huh? It gives you a glimpse of what kind of stuff Unity +has to deal with for every single test case. For each test case, we declare that +it is a new test. Then we run `setUp` and our test function. These are run +within a `TEST_PROTECT` block, the function of which is to handle failures that +occur during the test. Then, assuming our test is still running and hasn't been +ignored, we run `tearDown`. No matter what, our last step is to conclude this +test before moving on to the next. + +Let's say you need to add a call to `fsync` to force all of your output data to +flush to a file after each test. You could easily insert this after your +`UnityConcludeTest` call. Maybe you want to write an xml tag before and after +each result set. Again, you could do this by adding lines to this macro. Updates +to this macro are for the occasions when you need an action before or after +every single test case throughout your entire suite of tests. + + +## Happy Porting + +The defines and macros in this guide should help you port Unity to just about +any C target we can imagine. If you run into a snag or two, don't be afraid of +asking for help on the forums. We love a good challenge! + + +*Find The Latest of This And More at [ThrowTheSwitch.org](https://throwtheswitch.org)* |