Linux下GO语言内存共享,CGO实现

来源：互联网发布：折叠的北京知乎编辑：程序博客网时间：2024/05/01 22:26

package ceimport ("errors""fmt""os""os/exec")/*#include <stdio.h>#include <sys/shm.h>#include <stdlib.h>#include <sys/ipc.h>#include <string.h>int Size;int Shm_id;key_t Key;char *Shm_add;int getMem(char *pathname,int size){    Key = ftok((char *)pathname,0x03);    if(Key==-1)    {        return -1;    }    Shm_id=shmget(Key,size,IPC_CREAT|IPC_EXCL|0600);    if (Shm_id==-1)    {        return -2;    }    Shm_add=shmat(Shm_id,0,0);    if (Shm_add==(void *)-1)    {    return -3;    }    Size=size;    return 0;}int close(){    int result;    result=shmdt(Shm_add);    if (result != 0)    {        return result;    }    result=shmctl(Shm_id, IPC_RMID, NULL);    if (result != 0)    {        return result;    }    return 0;}int write(char *str){        int len;len=strlen(str);if (len >= Size){return 0;}strcpy((char *)Shm_add,(char *)str);return len;}char* read(){return (char *)Shm_add;}*/import "C"type Mem struct {Shm_id C.intsize   int}func GetShareMem(path string, size int) (*Mem, error) {info, err := os.Lstat(path)if err != nil {return nil, err}if info.IsDir() {return nil, errors.New("Must Is File")}cstr := C.CString(path)        num := C.getMem(cstr, C.int(size))        C.free(unsafe.Pointer(cstr))switch num {case 0:return &Mem{C.Shm_id, size}, nilcase -1:return nil, errors.New("Get Key error")case -2:return nil, errors.New("Get Shm_id error")case -3:C.close()return nil, errors.New("Map AddrSpace error")}C.close()return nil, errors.New("Unknow error")}func (self *Mem) Close() error {num := C.close() if num != 0 {cmd := exec.Command("ipcrm", "-m", fmt.Sprint(self.Shm_id))return cmd.Run()}return nil}func (self *Mem) Read() string {return C.GoString(C.read())}func (self *Mem) Write(body string) C.int {    if len(body) > self.size {        return C.int(0)    }    return C.write(C.CString(body))}

package mainimport ("flag""fmt")/*#include <stdio.h>#include <sys/shm.h>#include <sys/ipc.h>char* GetMem(int Shm_id){    char *Shm_add;    Shm_add=shmat(Shm_id,0,0);    if (Shm_add==(void *)-1)    {        return (char *)-1;    }    return (char *)Shm_add;}int close(char *Shm_add){int result;result=shmdt(Shm_add);    if (result != 0)    {        return result;    }}*/import "C"type ShareMem struct {Addr *C.char}func main() {i := flag.Int("m", 0, "-m=12345")flag.Parse()x := GetShareMem(*i)if x == nil {fmt.Println("open error")}defer x.Close()fmt.Println(x.Read())}func GetShareMem(shm_id int) *ShareMem {m,err := C.GetMem(C.int(shm_id))if err != nil {return nil}return &ShareMem{m}}func (self *ShareMem) Close() {C.close(self.Addr)}func (self *ShareMem) Read() string {return C.GoString(self.Addr)}

package mainimport (    "fmt"    "ce")func main() {m, err := ce.GetShareMem("/tmp/.tmpfile", 1024)if err != nil {fmt.Println(err)}defer m.Close()m.Write("fyxichen")fmt.Println(m.Read())}

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