安装使用clang-format

(Owed by: 春夜喜雨 http://blog.csdn.net/chunyexiyu)
参考：https://zhuanlan.zhihu.com/p/513588054

1、关于clang-format

clang-format用于格式化代码，并能够指定采用的格式名称，例如google，microsoft，GNU代码样式格式等。

在github上一些c/c++代码提交时，有些库明确要求代码格式需要使用clang-fomat格式化。

例如下面这个摘抄的说明：

Consistent Style: This project conforms to the Google C++ Style Guide. To ensure your changes are properly formatted please run:

clang-format -i --style=file <file>

2、centos上安装

首先yum search，找到远程库中有的clang-format包

$ sudo yum search clang-format
Last metadata expiration check: 1:27:55 ago on Tue 29 Nov 2022 08:27:57 AM CST.
Name & Summary Matched: clang-format
git-clang-format.x86_64 : Integration of clang-format for git
git-clang-format.i686 : Integration of clang-format for git

然后安装现有的clang-format包，就选git-clang-format.x86_64这个包吧

$ sudo yum install git-clang-format.x86_64
Last metadata expiration check: 1:24:22 ago on Tue 29 Nov 2022 08:27:57 AM CST.
Dependencies resolved.
…
Complete!

clang-format使用

查看clang-format的版本
$ clang-format --version
clang-format version 12.0.1 (Red Hat 12.0.1-4.module_el8.5.0+1025+93159d6c)

3、使用-格式化例子

例如下面代码的格式化：

$ cat main.c #include  "stdio.h"
int main()
{
printf("hello world");
return 0;
}

查看格式化后输出: 格式化后对齐好了很多

$ clang-format main.c
#include "stdio.h"
int main() {printf("hello world");return 0;
}

直接在源文件上格式化代码

$ clang-format -i main.c
$ cat main.c
#include "stdio.h"
int main() {printf("hello world");return 0;
}

指定格式化代码的风格： currently supports LLVM, GNU, Google, Chromium, Microsoft, Mozilla, WebKit.

$ clang-format -style=Google main.c
#include "stdio.h"
int main() {printf("hello world");return 0;
}
$ clang-format -style=Microsoft main.c
#include "stdio.h"
int main()
{printf("hello world");return 0;
}

附：使用帮助

命令帮助说明：

$ clang-format --help
OVERVIEW: A tool to format C/C++/Java/JavaScript/Objective-C/Protobuf/C# code.If no arguments are specified, it formats the code from standard input
and writes the result to the standard output.
If <file>s are given, it reformats the files. If -i is specified
together with <file>s, the files are edited in-place. Otherwise, the
result is written to the standard output.USAGE: clang-format [options] [<file> ...]OPTIONS:Clang-format options:--Werror                   - If set, changes formatting warnings to errors--Wno-error=<value>        - If set don't error out on the specified warning type.=unknown                 -   If set, unknown format options are only warned about.This can be used to enable formatting, even if theconfiguration contains unknown (newer) options.Use with caution, as this might lead to dramaticallydiffering format depending on an option beingsupported or not.--assume-filename=<string> - Override filename used to determine the language.When reading from stdin, clang-format assumes thisfilename to determine the language.--cursor=<uint>            - The position of the cursor when invokingclang-format from an editor integration--dry-run                  - If set, do not actually make the formatting changes--dump-config              - Dump configuration options to stdout and exit.Can be used with -style option.--fallback-style=<string>  - The name of the predefined style used as afallback in case clang-format is invoked with-style=file, but can not find the .clang-formatfile to use.Use -fallback-style=none to skip formatting.--ferror-limit=<uint>      - Set the maximum number of clang-format errors to emit before stopping (0 = no limit). Used only with --dry-run or -n-i                         - Inplace edit <file>s, if specified.--length=<uint>            - Format a range of this length (in bytes).Multiple ranges can be formatted by specifyingseveral -offset and -length pairs.When only a single -offset is specified without-length, clang-format will format up to the endof the file.Can only be used with one input file.--lines=<string>           - <start line>:<end line> - format a range oflines (both 1-based).Multiple ranges can be formatted by specifyingseveral -lines arguments.Can't be used with -offset and -length.Can only be used with one input file.-n                         - Alias for --dry-run--offset=<uint>            - Format a range starting at this byte offset.Multiple ranges can be formatted by specifyingseveral -offset and -length pairs.Can only be used with one input file.--output-replacements-xml  - Output replacements as XML.--sort-includes            - If set, overrides the include sorting behavior determined by the SortIncludes style flag--style=<string>           - Coding style, currently supports:LLVM, GNU, Google, Chromium, Microsoft, Mozilla, WebKit.Use -style=file to load style configuration from.clang-format file located in one of the parentdirectories of the source file (or currentdirectory for stdin).Use -style="{key: value, ...}" to set specificparameters, e.g.:-style="{BasedOnStyle: llvm, IndentWidth: 8}"--verbose                  - If set, shows the list of processed filesGeneric Options:--help                     - Display available options (--help-hidden for more)--help-list                - Display list of available options (--help-list-hidden for more)--version                  - Display the version of this program

(Owed by: 春夜喜雨 http://blog.csdn.net/chunyexiyu)