diff options
Diffstat (limited to 'src/libs/mynewt-nimble/CODING_STANDARDS.md')
| -rw-r--r-- | src/libs/mynewt-nimble/CODING_STANDARDS.md | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/src/libs/mynewt-nimble/CODING_STANDARDS.md b/src/libs/mynewt-nimble/CODING_STANDARDS.md new file mode 100644 index 00000000..d14b9fdb --- /dev/null +++ b/src/libs/mynewt-nimble/CODING_STANDARDS.md @@ -0,0 +1,267 @@ +# Coding Style for Apache NimBLE + +Apache NimBLE project is part of Apache Mynewt projct and follows its coding +style. + +# Coding Style for Apache Mynewt Core + +This document is meant to define the coding style for Apache Mynewt, and +all subprojects of Apache Mynewt. This covers C and Assembly coding +conventions, *only*. Other languages (such as Go), have their own +coding conventions. + +## Headers + +* All files that are newly written, should have the Apache License clause +at the top of them. + +* For files that are copied from another source, but contain an Apache +compatible license, the original license header shall be maintained. + +* For more information on applying the Apache license, the definitive +source is here: http://www.apache.org/dev/apply-license.html + +* The Apache License clause for the top of files is as follows: + +```no-highlight +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +``` + +## Whitespace and Braces + +* Code must be indented to 4 spaces, tabs should not be used. + +* Do not add whitespace at the end of a line. + +* Put space after keywords (for, if, return, switch, while). + +* for, else, if, while statements must have braces around their +code blocks, i.e., do: + +``` + if (x) { + assert(0); + } else { + assert(0); + } +``` + +Not: + +``` + if (x) + assert(0); + else + assert(0); +``` + +* Braces for statements must be on the same line as the statement. Good: + +``` + for (i = 0; i < 10; i++) { + if (i == 5) { + break; + } else { + continue; + } + } +``` + +Not: + +``` + for (i = 0; i < 10; i++) + { <-- brace must be on same line as for + if (i == 5) { + break; + } <-- no new line between else + else { + continue; + } + } +``` + +* After a function declaration, the braces should be on a newline, i.e. do: + +``` + static void * + function(int var1, int var2) + { +``` + +not: + +``` + static void * + function(int var1, int var2) { +``` + +## Line Length and Wrap + +* Line length should never exceed 79 columns. + +* When you have to wrap a long statement, put the operator at the end of the + line. i.e.: + +``` + if (x && + y == 10 && + b) +``` + +Not: + +``` + if (x + && y == 10 + && b) +``` + +## Comments + +* No C++ style comments allowed. + +* When using a single line comment, put it above the line of code that you +intend to comment, i.e., do: + +``` + /* check variable */ + if (a) { +``` + +Not: + +``` + if (a) { /* check variable */ +``` + + +* All public APIs should be commented with Doxygen style comments describing +purpose, parameters and return values. Private APIs need not be documented. + + +## Header files + +* Header files must contain the following structure: + * Apache License (see above) + * ```#ifdef``` aliasing, to prevent multiple includes + * ```#include``` directives for other required header files + * ```#ifdef __cplusplus``` wrappers to maintain C++ friendly APIs + * Contents of the header file + +* ```#ifdef``` aliasing, shall be in the following format, where +the package name is "os" and the file name is "callout.h": + +```no-highlight +#ifndef _OS_CALLOUT_H +#define _OS_CALLOUT_H +``` + +* ```#include``` directives must happen prior to the cplusplus +wrapper. + +* The cplusplus wrapper must have the following format, and precedes +any contents of the header file: + +```no-highlight +#ifdef __cplusplus +#extern "C" { +##endif +``` + +## Naming + +* Names of functions, structures and variables must be in all lowercase. + +* Names should be as short as possible, but no shorter. + +* Globally visible names must be prefixed with the name of the module, +followed by the '_' character, i.e.: + +``` + os_callout_init(&c) +``` + +Not: + +``` + callout_init(c) +``` + +## Functions + +* No spaces after function names when calling a function, i.e, do: + +``` + rc = function(a) +``` + +Not: + +``` + rc = function (a) +``` + + +* Arguments to function calls should have spaces between the comma, i.e. do: + +``` + rc = function(a, b) +``` + +Not: + +``` + rc = function(a,b) +``` + +* The function type must be on a line by itself preceding the function, i.e. do: + +``` + static void * + function(int var1, int var2) + { +``` + +Not: + +``` + static void *function(int var1, int var2) + { +``` + +* In general, for functions that return values that denote success or error, 0 +shall be success, and non-zero shall be the failure code. + +## Variables and Macros + +* Do not use typedefs for structures. This makes it impossible for +applications to use pointers to those structures opaquely. + +* typedef may be used for non-structure types, where it is beneficial to +hide or alias the underlying type used (e.g. ```os_time_t```.) Indicate +typedefs by applying the ```_t``` marker to them. + +* Place all function-local variable definitions at the top of the function body, before any statements. + +## Compiler Directives + +* Code must compile cleanly with -Wall enabled. + |