867 lines
31 KiB
Markdown
867 lines
31 KiB
Markdown
# KiCad C++ Source Code Style Guide #
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Latest Publishing: February 2017
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First Published: September 2010
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written by
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Wayne Stambaugh \<<stambaughw@gmail.com>\>
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and
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Dick Hollenbeck \<<dick@softplc.com>\>
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[TOC]
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# 1. Introduction # {#csp_intro}
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The purpose of this document is to provide a reference guide for KiCad
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developers about how source code should be styled and formatted in
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KiCad. It is not a comprehensive programming guide because it does not
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discuss many things such as software engineering strategies, source
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directories, existing classes, or how to internationalize text. The goal
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is to make all of the KiCad source conform to this guide.
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## 1.1 Why Coding Style Matters ## {#why}
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You may be thinking to yourself that using the style defined in this
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document will not make you a good programmer and you would be correct.
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Any given coding style is no substitute for experience. However, any
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experienced coder will tell that the only thing worse than looking at
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code that is not in your preferred coding style, is looking at twenty
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different coding styles that are not your preferred coding style.
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Consistency makes a) problems easier to spot, and b) looking at code for
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long periods of time more tolerable.
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## 1.2 Enforcement ## {#enforcement}
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The KiCad coding police are not going to break down your door and beat
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you with your keyboard if you don't follow these guidelines (although
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there are those who would argue that they should). However, there are
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some very sound reasons why you should follow them. If you are
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contributing patches, you are much more likely to be taken seriously by
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the primary developers if your patches are formatted correctly. Busy
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developers don't have the time to go back and reformat your code. If you
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have a desire to become a regular KiCad developer with commit access to
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the development branch, you're not likely to get a glowing
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recommendation by the lead developers if you will not follow these
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guidelines. It is just good programming courtesy to follow this policy
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because it is respectful of the investment already made by the existing
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developers. The other KiCad developers will appreciate your effort.
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**Warning**
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**Do not modify this document without the consent of the project
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leader. All changes to this document require approval.**
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## 1.3 Tools ## {#tools}
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There are some tools that can help you format your code easily.
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[`clang-format`][clang-format] is a formatting tool that can both be used to
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provide code-style automation to your editor of choice, as well as allow git to
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check formatting when committing (using a "Git hook"). You should install this
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program to be able to use the Git hooks.
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The style config file is `_clang-format`, and should be picked up automatically
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by `clang-format` when the `--style=file` option is set.
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To enable the Git hooks (only needs to be done once per Git repo):
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git config core.hooksPath .githooks
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Set the `git clang-format` tool to use the provided `_clang-format` file:
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git config clangFormat.style file
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Then, to enable the format checker, set the `kicad.check-format` Git config
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to "true" for the KiCad repo:
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git config kicad.check-format true
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Without this config, the format checker will not run on commit, but you can
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still check files staged for commit manually (see below).
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If the hook is enabled, when you commit a change, you will be told if you
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have caused any style violations (only in your changed code). You can then fix
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the errors, either manually, or with the tools below.
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If you are warned about formatting errors, but you are sure your style is correct,
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you can still commit:
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git commit --no-verify
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### Correcting Formatting Errors ## {#correcting-formatting-errors}
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There is a Git aliases file that provides the right commands to show and correct
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formatting errors. Add to your repository config by running this command from
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the source directory:
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git config --add include.path $(pwd)/helpers/git/format_alias
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Then you can use the following aliases:
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* `git check-format`: show any formatting warnings (but make no changes)
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* `git fix-format`: correct formatting (you will need to `git add` afterwards)
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These aliases use a script, `tools/check-coding.sh`, which takes care of only
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checking the formatting for files that should be formatted. This script has
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other uses:
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* Make (or see only) violations in files modified in the previous commit (useful
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when interactive-rebasing):
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* `check_coding.sh --amend [--diff]`
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# 2. Naming Conventions # {#naming_conventions}
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Before delving into anything as esoteric as indentation and formatting,
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naming conventions need to be addressed. This section does not attempt
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to define what names you use for your code. Rather, it defines the style
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for naming. See the references section for links to some excellent
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coding references. When defining multiple word names use the following
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conventions for improved readability:
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- Use underscores for all upper and all lower case variables to make
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multiple word names more readable.
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- Use camel case for mixed case variable names.
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Avoid mixing camel case and underscores.
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**Examples**
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~~~~~~~~~~~~~{.cpp}
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CamelCaseName // if camelcase, then no underscores
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all_lower_case_name
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ALL_UPPER_CASE_NAME
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~~~~~~~~~~~~~
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## 2.1 Class, Type Definitions, Name Space, and Macro Names ## {#definitions}
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Class, typedef, enum, name space, and macro names should be comprised of
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all capital letters.
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**Examples**
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~~~~~~~~~~~~~{.cpp}
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class SIMPLE
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#define LONG_MACRO_WITH_UNDERSCORES
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typedef boost::ptr_vector<PIN> PIN_LIST;
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enum KICAD_T {...};
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~~~~~~~~~~~~~
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## 2.2 Local, Private and Automatic Variables ## {#local_variables}
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The first character of automatic, static local, and private variable
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names should be lower case. This indicates that the variable will not be
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“visible” outside of the function, file, or class where they are
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defined, respectively. The limited visibility is being acknowledged with
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the lowercase starting letter, where lowercase is considered to be less
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boisterous than uppercase.
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**Examples**
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~~~~~~~~~~~~~{.cpp}
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int i;
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double aPrivateVariable;
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static char* static_variable = NULL;
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~~~~~~~~~~~~~
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## 2.3 Public and Global Variables ## {#global_variables}
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The first character of public and global variable names are to be
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uppercase. This indicates that the variable is visible outside the class
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or file in which it was defined. (An exception is the use of prefix `g_`
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which is also sometimes used to indicate a global variable.)
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**Example**
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~~~~~~~~~~~~~{.cpp}
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char* GlobalVariable;
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~~~~~~~~~~~~~
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## 2.4 Local, Private and Static Functions ## {#functions}
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The first character of local, private, and static functions should be
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lower case. This indicates that the function is not visible outside the
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class or file where it is defined.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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bool isModified();
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static int buildList( int* list );
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~~~~~~~~~~~~~
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## 2.5 Function Arguments ## {#function_arguments}
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Function arguments are prefixed with an 'a' to indicate these are
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arguments to a function. The 'a' stands for “argument”, and it also
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enables clever and concise Doxygen comments.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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/*/** */*
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* Copy aFoo into this instance.
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*/
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void SetFoo( int aFoo );
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~~~~~~~~~~~~~
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Notice how the reader can say “a Foo” to himself when reading this.
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## 2.6 Pointers ## {#pointers}
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It is not desired to identify a pointer by building a 'p' into the
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variable name. The pointer aspect of the variable pertains to type, not
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purpose.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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MODULE* module;
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~~~~~~~~~~~~~
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The purpose of the variable is that it represents a MODULE. Something
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like `p_module` would only make that harder to discern.
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## 2.7 Accessing Member Variables and Member Functions ## {#accessing_members}
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We do not use “`this->`” to access either member variables or member
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functions from within the containing class. We let C++ perform this for
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us.
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# 3. Commenting # {#commenting}
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Comments in KiCad typically fall into two categories: in line code
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comments and Doxygen comments. In line comments have no set formatting
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rules other than they should have the same indent level as the code if
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they do not follow a statement. In line comments that follow statements
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should not exceed 99 columns unless absolutely necessary. The prevents
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word wrapping in an editor when the viewable columns is set to 100. In
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line comments can use either the C++ or the C commenting style, but C++
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comments are preferred for single line comments or comments consisting
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of only a few lines.
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## 3.1 Blank Lines Above Comments ## {#blank_lines_above_comments}
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If a comment is the first thing on a line, then that comment should have
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one or more blank lines above them. One blank line is preferred.
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## 3.2 Doxygen ## {#doxygen}
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Doxygen is a C++ source code documenting tool used by the project. Descriptive
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*.html files can be generated from the source code by installing Doxygen and
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building the target named **doxygen-docs** and **dev-docs** that include this
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document.
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$ cd <kicad_build_base>
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$ make doxygen-docs
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The generated source \*.html files will be placed into
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\<kicad\_project\_base\>/Documentation/doxygen/html/ and the developer's
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\*.html files will be placed into
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\<kicad\_project\_base\>/Documentation/development/doxygen/html/
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Doxygen comments are used to build developer documentation from the
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source code. They should normally be only placed in header files and not
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in \*.cpp files. This eliminates the obligation to keep two comments in
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agreement with each other. If the class, function, or enum, etc. is
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only defined in a \*.cpp source file and not present in any header file,
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in which case the Doxygen comments should go into the \*.cpp source file.
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Again, avoid duplicating the Doxygen comments in both the header and
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\*.cpp source files.
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KiCad uses the JAVADOC comment style defined in the [“Documenting the
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code”][doccode] section of the Doxygen [manual][manual]. Don't forget
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to use the special Doxygen tags: bug, todo, deprecated, etc., so other
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developers can quickly get useful information about your code. It is
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good practice to actually generate the Doxygen \*.html files by
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building target doxygen-docs, and then to review the quality of your
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Doxygen comments with a web browser before submitting a patch.
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[doccode]: http://www.doxygen.nl/manual/docblocks.html
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[manual]: http://www.doxygen.nl/manual
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### 3.2.1 Function Comments ### {#function_comments}
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These go into a header file, unless the function is a private (i.e.
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static) function known only to a \*.cpp file. The format of a function
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comment is chosen to serve a dual purpose role: delineation of the
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function declaration within the source code and to create a consistent
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leading sentence in the doxygen html output. The chosen format is
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to use a descriptive single line sentence, followed by a blank line,
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followed by an optional detailed description as the shown in the example
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below.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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/*/** */*
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* Format and write text to an output stream.
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*
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* A really detailed description goes here if it's needed.
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*
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* @param aMestLevel is the multiple of spaces to precede the output with.
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* @param aFmt is a printf() style format string.
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* @param ... is a variable list of parameters that will get blended into
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* the output under control of the format string.
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* @return the number of characters output.
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* @throw IO_ERROR, if there is a problem outputting.
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*/
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int PRINTF_FUNC Print( int aNestLevel, const char* aFmt, ... );
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~~~~~~~~~~~~~
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The single line description goes on the 2nd line of the comment. The
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\@return keyword if present, should describe the return value followed
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by a hyphen. The \@param keyword names a function parameter and the text
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following should flow like a normal English sentence.
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### 3.2.2 Class Comments ### {#class_comments}
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A class comment describes a class declaration by giving the purpose and
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use of the class. Its format is similar to a function comment. Doxygen
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can use the html \<p\> (paragraph designation) to begin a new paragraph
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in its output. So if the text of the comment is large, break it put into
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multiple paragraphs.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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/*/** */*
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* An interface (abstract) class used to output UTF8 text in a
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* convenient way.
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*
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* The primary interface is "printf() like" but with support for
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* indentation control. The destination of the 8 bit wide text is
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* up to the implementer.
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* <p>
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* The implementer only has to implement the write() function, but
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* can also optionally re-implement GetQuoteChar().
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* <p>
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* If you want to output a wxString, then use CONV_TO_UTF8() on it
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* before passing it as an argument to Print().
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* <p>
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* Since this is an abstract interface, only classes derived from
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* this one may actually be used.
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*/
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class OUTPUTFORMATTER
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{
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~~~~~~~~~~~~~
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# 4. Formatting # {#formatting}
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This section defines the formatting style used in the KiCad source.
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## 4.1 Indentation ## {#indentation}
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The indentation level for the KiCad source code is defined as four
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spaces. Please do not use tabs.
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### 4.1.1 Defines ### {#defines}
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There should be only one space after a \#define statement.
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### 4.1.2 Column Alignment ### {#column_alignment}
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Please try to align multiple consecutive similar lines into consistent
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columns when possible, such as \#define lines which can be thought of as
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containing 4 columns: \#define, symbol, value, and comment. Notice how
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all 4 columns are aligned in the example below.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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#define LN_RED 12 // my favorite
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#define LN_GREEN 13 // eco friendly
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~~~~~~~~~~~~~
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Another common case is the declaration of automatic variables. These are
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preferably shown in columns of type and variable name.
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## 4.2 Blank Lines ## {#blank_lines}
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### 4.2.1 Function Declarations ### {#function_declarations}
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There should be 1 blank line above a function declaration in a class
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file if that function declaration is presented with a Javadoc comment.
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This is consist with the statement above about blank lines above
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comments.
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### 4.2.2 Function Definitions ### {#function_definitions}
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Function definitions in *.cpp files will not typically be accompanied by
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any comment, since those are normally only in the header file. It is
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desirable to set off the function definition within the *.cpp file by
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leaving two blank lines above the function definition.
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### 4.2.3 If Statements ### {#if_statements}
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There should be one blank line above if statements.
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## 4.3 Line Length ### {#line_length}
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The maximum line width is 99 columns. An exception to this is a long
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quoted string such as the internationalized text required to satisfy
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MSVC++, described below.
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## 4.4 Strings ## {#strings}
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The KiCad project team no longer supports compiling with Microsoft
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Visual C++. When you need to break long strings into smaller substrings,
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please use the C99 compliant method for improved readability. Using
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any of previously accepted methods defined below for breaking
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long internationalized strings will no longer be accepted.
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**Examples**
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~~~~~~~~~~~~~{.cpp}
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// This works with C99 compliant compilers is the **only** accepted method:
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wxChar* foo = _( “this is a long string broken ”
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“into pieces for readability.” );
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// This works with MSVC, breaks POEdit, and is **not** acceptable:
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wxChar* foo = _( “this is a long string broken ”
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L“into pieces for readability” );
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// This works with MSVC, is ugly, and is **not** accepted:
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wxChar* foo = _( “this is a long string \
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broken into pieces for readability” );
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~~~~~~~~~~~~~
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A second acceptable solution is to simply put the text all on one
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line, even if it exceeds the 99 character line length limit. However,
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the preferred method is to break strings within the 99 character limit
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whenever possible to prevent wrapping.
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## 4.5 Trailing Whitespace ## {#trailing_whitespace}
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Many programming editors conveniently indent your code for you. Some of
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them do it rather poorly and leave trailing whitespace. Thankfully, most
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editors come with a remove trailing whitespace macro or at least a
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setting to make trailing whitespace visible so you can see it and
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manually remove it. Trailing whitespace is known to break some text
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parsing tools. It also leads to unnecessary diffs in the version control
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system. Please remove trailing whitespace.
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## 4.6 Multiple Statements per Line ## {#multiple_statements_per_line}
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It is generally preferred that each statement be placed on its own line.
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This is especially true for statements without keywords.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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x=1; y=2; z=3; // Bad, should be on separate lines.
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~~~~~~~~~~~~~
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## 4.7 Braces ## {#braces}
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Braces should be placed on the line proceeding the keyword and indented
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to the same level. It is not necessary to use braces if there is only a
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single line statement after the keyword. In the case of if..else
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if..else, indent all to the same level.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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void function()
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{
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if( foo )
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{
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statement1;
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statement2;
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}
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else if( bar )
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{
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statement3;
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statement4;
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}
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else
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statement5;
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}
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~~~~~~~~~~~~~
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## 4.8 Parenthesis ## {#parenthesis}
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Parenthesis should be placed immediately after function names and
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keywords. Spaces should be placed after the opening parenthesis, before
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the closing parenthesis, and between the comma and the next argument in
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functions. No space is needed if a function has no arguments.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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void Function( int aArg1, int aArg2 )
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{
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while( busy )
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{
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if( a || b || c )
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doSomething();
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else
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doSomethingElse();
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}
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}
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~~~~~~~~~~~~~
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## 4.9 Switch Formatting ## {#switch}
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The case statement is to be indented to the same level as the switch.
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**Example**
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~~~~~~~~~~~~~{.cpp}
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switch( foo )
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{
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case 1:
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doOne();
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break;
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case 2:
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doTwo();
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// Fall through.
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default:
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doDefault();
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}
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~~~~~~~~~~~~~
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It is permitted to place all cases on a single line each, if that makes the
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code more readable. This is often done for look-ups or translation functions. In
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this case, you will have to manually align for readability as appropriate and
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reject clang-format's suggested changes, if you use it:
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~~~~~~~~~~~~~{.cpp}
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switch( m_orientation )
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{
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case PIN_RIGHT: m_orientation = PIN_UP; break;
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case PIN_UP: m_orientation = PIN_LEFT; break;
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case PIN_LEFT: m_orientation = PIN_DOWN; break;
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case PIN_DOWN: m_orientation = PIN_RIGHT; break;
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}
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~~~~~~~~~~~~~
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# 5. License Statement # {#license_statement}
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There is a the file copyright.h which you can copy into the top of
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your new source files and edit the \<author\> field. KiCad depends on
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the copyright enforcement capabilities of copyright law, and this
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means that source files must be copyrighted and not be released into
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the public domain. Each source file has one or more owners.
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# 6. Header Files # {#header_files}
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Project \*.h source files should:
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|
|
- contain a license statement
|
|
- contain a nested include \#ifndef
|
|
- be fully self standing and not depend on other headers that are not
|
|
included within it.
|
|
|
|
The license statement was described above.
|
|
|
|
## 6.1 Nested Include #ifndef ## {#nested_include}
|
|
Each header file should include an \#ifndef which is commonly used to
|
|
prevent compiler errors in the case where the header file is seen
|
|
multiple times in the code stream presented to the compiler. Just
|
|
after the license statement, at the top of the file there should be
|
|
lines similar to these (but with a file name specific token other than
|
|
`RICHIO_H_`):
|
|
|
|
~~~~~~~~~~~~~{.cpp}
|
|
#ifndef RICHIO_H_
|
|
#define RICHIO_H_
|
|
~~~~~~~~~~~~~
|
|
|
|
And at the very bottom of the header file, use a line like this one:
|
|
|
|
~~~~~~~~~~~~~{.cpp}
|
|
#endif // RICHIO_H_
|
|
~~~~~~~~~~~~~
|
|
|
|
The \#ifndef wrapper begins after the license statement, and ends at
|
|
the very bottom of the file. It is important that it wrap any nested
|
|
\#include statements, so that the compiler can skip them if the
|
|
\#ifndef evaluates to false, which will reduce compilation time.
|
|
|
|
## 6.2 Headers Without Unsatisfied Dependencies ## {#header_depends}
|
|
Any header file should include other headers that it depends on. (Note:
|
|
KiCad is not at this point now, but this section is a goal of the
|
|
project.)
|
|
|
|
It should be possible to run the compiler on any header file within the
|
|
project, and with proper include paths being passed to the compiler, the
|
|
header file should compile without error.
|
|
|
|
**Example**
|
|
|
|
$ cd /svn/kicad/testing.checkout/include
|
|
$ g++ wx-config --cxxflags -I . xnode.h -o /tmp/junk
|
|
|
|
Such structuring of the header files removes the need within a client
|
|
\*.cpp file to include some project header file before some other project
|
|
header file. (A client \*.cpp file is one that intends to **use, not
|
|
implement,** the public API exposed within the header file.)
|
|
|
|
Client code should not have to piece together things that a header file
|
|
wishes to expose. The exposing header file should be viewed as a fully
|
|
sufficient **ticket to use** the public API of that header file.
|
|
|
|
This is not saying anything about how much to expose, only that that
|
|
which is exposed needs to be fully usable merely by including the header
|
|
file that exposes it, with no additional includes.
|
|
|
|
For situations where there is a class header file and an
|
|
implementation \*.cpp file, it is desirable to hide as much of the
|
|
private implementation as is practical and any header file that is not
|
|
needed as part of the public API can and should be included only in
|
|
the implementation \*.cpp file. However, the number one concern of
|
|
this section is that client (using) code can use the public API which
|
|
is exposed in the header file, merely by including that one header
|
|
file.
|
|
|
|
|
|
# 7. I Wrote X Lines of Code Before I Read This Document # {#x_lines}
|
|
It's OK. We all make mistakes. Fortunately, KiCad provides a
|
|
configuration file for the code beautifier uncrustify. Uncrustify won't
|
|
fix your naming problems but it does a pretty decent job of formatting
|
|
your source code. There are a few places where uncrustify makes some
|
|
less than ideal indentation choices. It struggles with the string
|
|
declaration macros wxT(“”) and \_(“”) and functions used as arguments to
|
|
other functions. After you uncrustify your source code, please review the
|
|
indentation for any glaring errors and manually fix them. See the
|
|
uncrustify [website][uncrustify] for more information.
|
|
|
|
[uncrustify]: http://uncrustify.sourceforge.net/
|
|
|
|
|
|
# 8. Show Me an Example # {#show_me_an_example}
|
|
Nothing drives the point home like an example. The source file richio.h
|
|
below was taken directly from the KiCad source.
|
|
|
|
~~~~~~~~~~~~~{.cpp}
|
|
/*
|
|
* This program source code file is part of KICAD, a free EDA CAD application.
|
|
*
|
|
* Copyright (C) 2007-2010 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
|
|
* Copyright (C) 2007 KiCad Developers, see change_log.txt for contributors.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, you may find one here:
|
|
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
|
|
* or you may search the http://www.gnu.org website for the version 2 license,
|
|
* or you may write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
|
|
*/
|
|
|
|
#ifndef RICHIO_H_
|
|
#define RICHIO_H_
|
|
|
|
|
|
// This file defines 3 classes useful for working with DSN text files and is named
|
|
// "richio" after its author, Richard Hollenbeck, aka Dick Hollenbeck.
|
|
|
|
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
// I really did not want to be dependent on wxWidgets in richio
|
|
// but the errorText needs to be wide char so wxString rules.
|
|
#include <wx/wx.h>
|
|
#include <cstdio> // FILE
|
|
|
|
|
|
|
|
/*/** */*
|
|
* A class used to hold an error message and may be used to throw exceptions
|
|
* containing meaningful error messages.
|
|
*/
|
|
struct IOError
|
|
{
|
|
wxString errorText;
|
|
|
|
IOError( const wxChar* aMsg ) :
|
|
errorText( aMsg )
|
|
{
|
|
}
|
|
|
|
IOError( const wxString& aMsg ) :
|
|
errorText( aMsg )
|
|
{
|
|
}
|
|
};
|
|
|
|
|
|
/*/** */*
|
|
* Read single lines of text into a buffer and increments a line number counter.
|
|
*/
|
|
class LINE_READER
|
|
{
|
|
protected:
|
|
|
|
FILE* fp;
|
|
int lineNum;
|
|
unsigned maxLineLength;
|
|
unsigned length;
|
|
char* line;
|
|
unsigned capacity;
|
|
|
|
public:
|
|
|
|
/*/** */*
|
|
* @param aFile is an open file in "ascii" mode, not binary mode.
|
|
* @param aMaxLineLength is the number of bytes to use in the line buffer.
|
|
*/
|
|
LINE_READER( FILE* aFile, unsigned aMaxLineLength );
|
|
|
|
~LINE_READER()
|
|
{
|
|
delete[] line;
|
|
}
|
|
|
|
/*
|
|
int CharAt( int aNdx )
|
|
{
|
|
if( (unsigned) aNdx < capacity )
|
|
return (char) (unsigned char) line[aNdx];
|
|
return -1;
|
|
}
|
|
*/
|
|
|
|
/*/** */*
|
|
* Read a line of text into the buffer and increments the line number
|
|
* counter.
|
|
*
|
|
* @return is the number of bytes read, 0 at end of file.
|
|
* @throw IO_ERROR when a line is too long.
|
|
*/
|
|
int ReadLine();
|
|
|
|
operator char* ()
|
|
{
|
|
return line;
|
|
}
|
|
|
|
int LineNumber()
|
|
{
|
|
return lineNum;
|
|
}
|
|
|
|
unsigned Length()
|
|
{
|
|
return length;
|
|
}
|
|
};
|
|
|
|
|
|
|
|
/*/** */*
|
|
* An interface (abstract class) used to output ASCII text in a convenient way.
|
|
*
|
|
* The primary interface is printf() like with support for indentation control.
|
|
* The destination of the 8 bit wide text is up to the implementer. If you want
|
|
* to output a wxString, then use CONV_TO_UTF8() on it before passing it as an
|
|
* argument to Print().
|
|
* <p>
|
|
* Since this is an abstract interface, only classes derived from this one
|
|
* will be the implementations.
|
|
* </p>
|
|
*/
|
|
class OUTPUTFORMATTER
|
|
{
|
|
|
|
#if defined(__GNUG__) // The GNU C++ compiler defines this
|
|
|
|
// When used on a C++ function, we must account for the "this" pointer,
|
|
// so increase the STRING-INDEX and FIRST-TO_CHECK by one.
|
|
// See http://docs.freebsd.org/info/gcc/gcc.info.Function_Attributes.html
|
|
// Then to get format checking during the compile, compile with -Wall or -Wformat
|
|
#define PRINTF_FUNC __attribute__ ((format (printf, 3, 4)))
|
|
|
|
#else
|
|
#define PRINTF_FUNC // nothing
|
|
#endif
|
|
|
|
public:
|
|
|
|
/*/** */*
|
|
* Format and write text to the output stream.
|
|
*
|
|
* @param nestLevel is the multiple of spaces to preceed the output with.
|
|
* @param fmt is a printf() style format string.
|
|
* @param ... is a variable list of parameters that will get blended into
|
|
* the output under control of the format string.
|
|
* @return the number of characters output.
|
|
* @throw IO_ERROR if there is a problem outputting, such as a full disk.
|
|
*/
|
|
virtual int PRINTF_FUNC Print( int nestLevel, const char* fmt, ... ) = 0;
|
|
|
|
/*/** */*
|
|
* Return the quoting character required for aWrapee.
|
|
*
|
|
* Return the quote character as a single character string for a given
|
|
* input wrapee string. If the wrappee does not need to be quoted,
|
|
* the return value is "" (the null string), such as when there are no
|
|
* delimiters in the input wrapee string. If you want the quote character
|
|
* to be assuredly not "", then pass in "(" as the wrappee.
|
|
* <p>
|
|
* Implementations are free to override the default behavior, which is to
|
|
* call the static function of the same name.
|
|
* </p>
|
|
*
|
|
* @param aWrapee is a string that might need wrapping on each end.
|
|
* @return the quote character as a single character string, or ""
|
|
* if the wrapee does not need to be wrapped.
|
|
*/
|
|
virtual const char* GetQuoteChar( const char* aWrapee ) = 0;
|
|
|
|
virtual ~OUTPUTFORMATTER() {}
|
|
|
|
/*/** */*
|
|
* Get the quote character according to the Specctra DSN specification.
|
|
*
|
|
* @param aWrapee is a string that might need wrapping on each end.
|
|
* @param aQuoteChar is a single character C string which provides the current
|
|
* quote character, should it be needed by the wrapee.
|
|
*
|
|
* @return the quote_character as a single character string, or ""
|
|
* if the wrapee does not need to be wrapped.
|
|
*/
|
|
static const char* GetQuoteChar( const char* aWrapee, const char* aQuoteChar );
|
|
};
|
|
|
|
|
|
/*/** */*
|
|
* Implement an OUTPUTFORMATTER to a memory buffer.
|
|
*/
|
|
class STRINGFORMATTER : public OUTPUTFORMATTER
|
|
{
|
|
std::vector<char> buffer;
|
|
std::string mystring;
|
|
|
|
int sprint( const char* fmt, ... );
|
|
int vprint( const char* fmt, va_list ap );
|
|
|
|
public:
|
|
|
|
/*/** */*
|
|
* Reserve space in the buffer
|
|
*/
|
|
STRINGFORMATTER( int aReserve = 300 ) :
|
|
buffer( aReserve, '\0' )
|
|
{
|
|
}
|
|
|
|
|
|
/*/** */*
|
|
* Clears the buffer and empties the internal string.
|
|
*/
|
|
void Clear()
|
|
{
|
|
mystring.clear();
|
|
}
|
|
|
|
/*/** */*
|
|
* Remove whitespace, '(', and ')' from the internal string.
|
|
*/
|
|
void StripUseless();
|
|
|
|
|
|
std::string GetString()
|
|
{
|
|
return mystring;
|
|
}
|
|
|
|
|
|
//-----<OUTPUTFORMATTER>------------------------------------------------
|
|
int PRINTF_FUNC Print( int nestLevel, const char* fmt, ... );
|
|
const char* GetQuoteChar( const char* wrapee );
|
|
//-----</OUTPUTFORMATTER>-----------------------------------------------
|
|
};
|
|
|
|
|
|
#endif // RICHIO_H_
|
|
~~~~~~~~~~~~~
|
|
|
|
|
|
# 9. Resources # {#resources}
|
|
There are plenty of excellent resources on the Internet on C++ coding
|
|
styles and coding do's and don'ts. Here are a few useful ones. In most
|
|
cases, the coding styles do not follow the KiCad coding style but there
|
|
is plenty of other good information here. Besides, most of them have
|
|
some great humor in them enjoyable to read. Who knows, you might even
|
|
learn something new.
|
|
|
|
- [C++ Coding Standard][cppstandard]
|
|
- [Linux Kernel Coding Style][kernel]
|
|
- [C++ Operator Overloading Guidelines][overloading]
|
|
- [Wikipedia's Programming Style Page][style]
|
|
|
|
[clang-format]: https://clang.llvm.org/docs/ClangFormat.html
|
|
[cppstandard]:http://www.possibility.com/Cpp/CppCodingStandard.html
|
|
[kernel]:https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/Documentation/process/coding-style.rst
|
|
[overloading]:http://www.cs.caltech.edu/courses/cs11/material/cpp/donnie/cpp-ops.html
|
|
[style]:http://en.wikipedia.org/wiki/Programming_style
|