//
// Created by xajhuang on 2023/3/2.
//
#include <fcntl.h>
#include <sys/file.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include "user_errno.h"
#include "misc.h"
static int  g_lockfd            = -1;
static char g_pidPath[MAX_PATH] = {0};

int process_lock_pidfile(char *pFilePath) {
    if (pFilePath == NULL || strlen(pFilePath) == 0) {
        return ERR_SUCCESS;
    }

    strcpy(g_pidPath, pFilePath);

    g_lockfd = open(pFilePath, O_CREAT | O_RDWR, 0666);    // open file
    int rc   = flock(g_lockfd, LOCK_EX | LOCK_NB);         // lock access to open file
    if (rc && EWOULDBLOCK == errno) {                      // check lock success
        return -ERR_FILE_LOCKED;                           // another instance is running
    }

    return ERR_SUCCESS;
}

void process_unlock_pidfile() {
    close(g_lockfd);
    unlink(g_pidPath);
}