在现有的C项目中使用Go代码

问题描述：

Ever since Go 1.5 came out, I started taking another look at how I could integrate it into an existing project of mine.

The project's codebase is written entirely in C for low level access to to hardware and other fun stuff. However, some of the higher level things are tedious, and I would like to start writing them in a higher level language (Go)

Is there any way I can call Go code from a C program? I installed Go 1.5, which added -buildmode=c-archive (https://golang.org/s/execmodes) which I am trying to get working.

However, I can't seem to get Go to generate the appropriate header files to allow my project to actually compile. When I generate the archive, I see the function in the exported symbols (using objdump), but without the header files to include gcc complains about the function not existing (as expected)

I'm quite new to Go - however, I love the language and would like to make use of it. Is there any idiomatic way ("idiomatic" gets used a lot in the world of Go I see...) to get this to play nicely with each other?

The reason I asked this question and specifically mentioned Go 1.5 is that according to this document, https://docs.google.com/document/d/1nr-TQHw_er6GOQRsF6T43GGhFDelrAP0NqSS_00RgZQ/edit?pli=1#heading=h.1gw5ytjfcoke Go 1.5 added support for non-Go programs to call Go code. Specifically, mentioned under the section "Go code linked into, and called from, a non-Go program"

自从Go 1.5发布以来，我开始着眼于如何将其集成到我现有的项目中 p>

该项目的代码库完全使用C语言编写，可用于低级访问硬件和其他有趣的东西。但是，有些高级的东西很乏味，我想开始用高级语言（Go）编写它们。 p>

有什么方法可以从C调用Go代码？程序？我安装了Go 1.5，它添加了-buildmode = c-archive code>（ https://golang.org/s/execmodes ）。 p>

但是，我似乎无法让Go生成适当的头文件来实际编译我的项目。生成归档文件时，我在导出的符号中看到了该函数（使用objdump），但是没有包含gcc的头文件，抱怨该函数不存在（按预期） p>


 I' 对Go语言来说，这是很陌生的-但是，我喜欢这种语言，并且想利用它。 是否有任何惯用的方式（我在Go的世界中经常使用“惯用的” ...）来使它们相互配合？ p> 
 
 
我问这个的原因 问题并特别提到的Go 1.5是根据此文档， https  ：//docs.google.com/document/d/1nr-TQHw_er6GOQRsF6T43GGhFDelrAP0NqSS_00RgZQ/edit？pli = 1＃heading = h.1gw5ytjfcoke  
Go 1.5添加了对非Go程序调用Go代码的支持。 具体来说，在“链接到非Go程序并从中调用的Go代码”一节中提到 p> 
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答

To build an archive callable from C, you will need to mark them as exported CGo symbols.
For example, if I create a file foo.go with the following contents:

package main

import (
    "C"
    "fmt"
)

//export PrintInt
func PrintInt(x int) {
    fmt.Println(x)
}

func main() {}

The important things to note are:

The package needs to be called main
You need to have a main function, although it can be empty.
You need to import the package C
You need special //export comments to mark the functions you want callable from C.

I can compile it as a C callable static library with the following command:

go build -buildmode=c-archive foo.go

The results will be an archive foo.a and a header foo.h. In the header, we get the following (eliding irrelevant parts):

...
typedef long long GoInt64;
...
typedef GoInt64 GoInt;
...
extern void PrintInt(GoInt p0);
...

So that's enough to call the exported function. We can write a simple C program that calls it like so:

#include "foo.h"

int main(int argc, char **argv) {
    PrintInt(42);
    return 0;
}

We can compile it with a command like:

gcc -pthread foo.c foo.a -o foo

The -pthread option is needed because the Go runtime makes use of threads. When I run the resulting executable it prints 42.

在现有的C项目中使用Go代码

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