1. 数值类型
python3 支持的 c 语言类型
参考 https://docs.python.org/3/library/ctypes.html
| ctypes type | C type | Python type |
|---|---|---|
| c_bool | _Bool | bool (1) |
| c_char | char | 1-character bytes object |
| c_wchar | wchar_t | 1-character string |
| c_byte | char | int |
| c_ubyte | unsigned?char | int |
| c_short | short | int |
| c_ushort | unsigned?short | int |
| c_int | int | int |
| c_uint | unsigned?int | int |
| c_long | long | int |
| c_ulong | unsigned?long | int |
| c_longlong | __int64?or?long?long | int |
| c_ulonglong | unsigned?__int64?or?unsigned?long?long | int |
| c_size_t | size_t | int |
| c_ssize_t | ssize_t?or?Py_ssize_t | int |
| c_float | float | float |
| c_double | double | float |
| c_longdouble | long?double | float |
| c_char_p | char?*?(NUL terminated) | bytes object or?None |
| c_wchar_p | wchar_t?*?(NUL terminated) | string or?None |
| c_void_p | void?* | int or?None |
golang 支持的数值类型
参考 https://chai2010.cn/advanced-go-programming-book/ch2-cgo/ch2-03-cgo-types.html
| C 语言类型 | CGO 类型 | Go 语言类型 |
|---|---|---|
| char | C.char | byte |
| singed char | C.schar | int8 |
| unsigned char | C.uchar | uint8 |
| short | C.short | int16 |
| unsigned short | C.ushort | uint16 |
| int | C.int | int32 |
| unsigned int | C.uint | uint32 |
| long | C.long | int32 |
| unsigned long | C.ulong | uint32 |
| long long int | C.longlong | int64 |
| unsigned long long int | C.ulonglong | uint64 |
| float | C.float | float32 |
| double | C.double | float64 |
| size_t | C.size_t | uint |
python 和 golang 的数据类型对应
| ctypes type | C type | Python type | CGO 类型 | Go 语言类型 |
|---|---|---|---|---|
| c_char | char | 1-character bytes object | C.char | byte |
| c_ubyte | unsigned?char | int | C.uchar | uint8 |
| c_short | short | int | C.short | int16 |
| c_ushort | unsigned?short | int | C.ushort | uint16 |
| c_int | int | int | C.int | int32 |
| c_uint | unsigned?int | int | C.uint | uint32 |
| c_long | long | int | C.long | int32 |
| c_ulong | unsigned?long | int | C.ulong | uint32 |
| c_longlong | __int64?or?long?long | int | C.longlong | int64 |
| c_ulonglong | unsigned?__int64?or?unsigned?long?long | int | C.ulonglong | uint64 |
| c_size_t | size_t | int | C.size_t | uint |
| c_float | float | float | C.float | float32 |
| c_double | double | float | C.double | float64 |
2. 编写 golang 文件
test.go
// libadd.go
package main
import "C" // 声明使用了 cgo，这样才能编写出 C 兼容的动态链接库
// 需要在 Add() 函数上加 //export Add 注释，告诉编译器，Add() 可以供其他程序调用
//export Add
func Add(a, b int) int {return a + b}
//export AddFloat
func AddFloat(a, b float64) float64 {return a + b}
func main(){}
编译 dll
go build -ldflags "-s -w" -o test.dll -buildmode=c-shared test.go
3. 在 python 文件中调用扩展
test.py
import ctypes
lib = ctypes.cdll.LoadLibrary('./test.dll')
lib.AddFloat.argtypes = [ctypes.c_double, ctypes.c_double]
lib.AddFloat.restype = ctypes.c_double
result = lib.AddFloat(100, 200)
print(result)
result = lib.Add(100, 200)
print(result)
输出：
>python test.py
300.0
300
