windows下子进程支持日志重定向、等待子进程推出、获取子进程退出码等特性

b08ea0fc · xiongziliang · 8ef8c91f · b08ea0fc · b08ea0fc
Commit b08ea0fc authored Jun 08, 2020 by xiongziliang
--- a/server/FFmpegSource.cpp
+++ b/server/FFmpegSource.cpp
@@ -24,19 +24,16 @@ const string kSnap = FFmpeg_FIELD"snap";
 onceToken token([]() {
 #ifdef _WIN32
-    string ffmpeg_bin = System::execute("where ffmpeg");
+    string ffmpeg_bin = trim(System::execute("where ffmpeg"));
-    //windows下先关闭FFmpeg日志(目前不支持日志重定向)
-    mINI::Instance()[kCmd] = "%s -re -i %s -loglevel quiet -c:a aac -strict -2 -ar 44100 -ab 48k -c:v libx264 -f flv %s";
-    mINI::Instance()[kSnap] = "%s -i %s -loglevel quiet -y -f mjpeg -t 0.001 %s";
 #else
-    string ffmpeg_bin = System::execute("which ffmpeg");
+    string ffmpeg_bin = trim(System::execute("which ffmpeg"));
-    mINI::Instance()[kCmd] = "%s -re -i %s -c:a aac -strict -2 -ar 44100 -ab 48k -c:v libx264 -f flv %s";
-    mINI::Instance()[kSnap] = "%s -i %s -y -f mjpeg -t 0.001 %s";
 #endif
    //默认ffmpeg命令路径为环境变量中路径
    mINI::Instance()[kBin] = ffmpeg_bin.empty() ? "ffmpeg" : ffmpeg_bin;
    //ffmpeg日志保存路径
    mINI::Instance()[kLog] = "./ffmpeg/ffmpeg.log";
+    mINI::Instance()[kCmd] = "%s -re -i %s -c:a aac -strict -2 -ar 44100 -ab 48k -c:v libx264 -f flv %s";
+    mINI::Instance()[kSnap] = "%s -i %s -y -f mjpeg -t 0.001 %s";
 });
 }

--- a/server/Process.cpp
+++ b/server/Process.cpp
@@ -16,6 +16,7 @@
 #else
 //#include <TlHelp32.h>
 #include <windows.h>
+#include <io.h>
 #endif
 #include <stdexcept>
@@ -31,23 +32,44 @@ using namespace toolkit;
 void Process::run(const string &cmd, const string &log_file_tmp) {
    kill(2000);
 #ifdef _WIN32
-    STARTUPINFO si;
+    STARTUPINFO si = {0};
-    PROCESS_INFORMATION pi;
+    PROCESS_INFORMATION pi = {0};
-    ZeroMemory(&si, sizeof(si));			//结构体初始化；
+    string log_file;
-    ZeroMemory(&pi, sizeof(pi));
+    if (log_file_tmp.empty()) {
+        //未指定子进程日志文件时，重定向至/dev/null
+        log_file = "NUL";
+    }
+    else {
+        log_file = StrPrinter << log_file_tmp << "." << getCurrentMillisecond();
+    }
-    LPTSTR lpDir = const_cast<char*>(cmd.data());
+    //重定向shell日志至文件
+    auto fp = File::create_file(log_file.data(), "ab");
+    if (!fp) {
+        fprintf(stderr, "open log file %s failed:%d(%s)\r\n", log_file.data(), errno, strerror(errno));
+    } else {
+        auto log_fd = (HANDLE)(_get_osfhandle(fileno(fp)));
+        // dup to stdout and stderr.
+        si.wShowWindow = SW_HIDE;
+        // STARTF_USESHOWWINDOW:The wShowWindow member contains additional information.   
+        // STARTF_USESTDHANDLES:The hStdInput, hStdOutput, and hStdError members contain additional information.    
+        si.dwFlags = STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
+        si.hStdError = log_fd;
+        si.hStdOutput = log_fd;
+    }
-    if (CreateProcess(NULL, lpDir, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi)){
+    LPTSTR lpDir = const_cast<char*>(cmd.data());
+    if (CreateProcess(NULL, lpDir, NULL, NULL, TRUE, 0, NULL, NULL, &si, &pi)){
        //下面两行关闭句柄，解除本进程和新进程的关系，不然有可能 不小心调用TerminateProcess函数关掉子进程 
        CloseHandle(pi.hProcess);
        CloseHandle(pi.hThread);
        _pid = pi.dwProcessId;
+		fprintf(fp, "\r\n\r\n#### pid=%d,cmd=%s #####\r\n\r\n", _pid, cmd.data());
        InfoL << "start child proces " << _pid;
    } else {
-        WarnL << "start child proces fail: " << GetLastError();
+        WarnL << "start child proces fail: " << get_uv_errmsg();
    }
+	fclose(fp);
 #else	
    _pid = fork();
    if (_pid < 0) {
@@ -125,16 +147,42 @@ static bool s_wait(pid_t pid,int *exit_code_ptr,bool block) {
    if (pid <= 0) {
        return false;
    }
-    int status = 0;
 #ifdef _WIN32
    HANDLE hProcess = NULL;
-    hProcess = OpenProcess(PROCESS_TERMINATE, FALSE, pid);	//打开目标进程
+    hProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, pid);	//打开目标进程
-    if (hProcess == NULL) {
+    if (!hProcess) {
+        WarnL << "OpenProcess failed:" << get_uv_errmsg();
+        return false;
+    }
+    DWORD code = 0;
+    if (block) {
+        //一直等待
+        code = WaitForSingleObject(hProcess, INFINITE);
+    } else {
+        code = WaitForSingleObject(hProcess, 0);
+    }
+    if(code == WAIT_FAILED || code == WAIT_OBJECT_0){
+        //子进程已经退出了,获取子进程退出代码
+        DWORD exitCode = 0;
+        if(GetExitCodeProcess(hProcess, &exitCode) && exit_code_ptr){
+            *exit_code_ptr = exitCode;
+        }
+        CloseHandle(hProcess);
        return false;
    }
    CloseHandle(hProcess);
+    if(code == WAIT_TIMEOUT){
+        //子进程还在线
+        return true;
+    }
+	//不太可能运行到此处
+    WarnL << "WaitForSingleObject ret:" << code;
+    return false;
 #else
+    int status = 0;
    pid_t p = waitpid(pid, &status, block ? 0 : WNOHANG);
    int exit_code = (status & 0xFF00) >> 8;
    if (exit_code_ptr) {
@@ -148,10 +196,41 @@ static bool s_wait(pid_t pid,int *exit_code_ptr,bool block) {
        InfoL << "process terminated, pid=" << pid << ", exit code=" << exit_code;
        return false;
    }
+    return true;
 #endif // _WIN32
+}
-    return true;
+#ifdef _WIN32
+// Inspired from http://stackoverflow.com/a/15281070/1529139
+// and http://stackoverflow.com/q/40059902/1529139
+bool signalCtrl(DWORD dwProcessId, DWORD dwCtrlEvent){
+    bool success = false;
+    DWORD thisConsoleId = GetCurrentProcessId();
+    // Leave current console if it exists
+    // (otherwise AttachConsole will return ERROR_ACCESS_DENIED)
+    bool consoleDetached = (FreeConsole() != FALSE);
+    if (AttachConsole(dwProcessId) != FALSE){
+        // Add a fake Ctrl-C handler for avoid instant kill is this console
+        // WARNING: do not revert it or current program will be also killed
+        SetConsoleCtrlHandler(nullptr, true);
+        success = (GenerateConsoleCtrlEvent(dwCtrlEvent, 0) != FALSE);
+        FreeConsole();
+    }
+    if (consoleDetached){
+        // Create a new console if previous was deleted by OS
+        if (AttachConsole(thisConsoleId) == FALSE){
+            int errorCode = GetLastError();
+            if (errorCode == 31){
+                // 31=ERROR_GEN_FAILURE
+                AllocConsole();
+            }
+        }
+    }
+    return success;
 }
+#endif // _WIN32
 static void s_kill(pid_t pid,int max_delay,bool force){
    if (pid <= 0) {
@@ -161,13 +240,20 @@ static void s_kill(pid_t pid,int max_delay,bool force){
 #ifdef _WIN32
    HANDLE hProcess = NULL;
    hProcess = OpenProcess(PROCESS_TERMINATE, FALSE, pid);	//打开目标进程
-    if (hProcess == NULL) {
+    if (!hProcess) {
-        WarnL << "\nOpen Process fAiled: " << GetLastError();
+		//子进程可能已经推出了
        return;
    }
+    if(force){
+        //强制关闭
        DWORD ret = TerminateProcess(hProcess, 0);	//结束目标进程
+        CloseHandle(hProcess);
        if (ret == 0) {
-        WarnL << GetLastError;
+            WarnL << "TerminateProcess " << pid << " failed:" << get_uv_errmsg();
+        }
+    }else{
+        //非强制关闭，发生Ctr+C信号
+        signalCtrl(pid, CTRL_C_EVENT);
    }
 #else
    if (::kill(pid, force ? SIGKILL : SIGTERM) == -1) {
@@ -177,7 +263,6 @@ static void s_kill(pid_t pid,int max_delay,bool force){
    }
 #endif // _WIN32
    if(force){
        //发送SIGKILL信号后，阻塞等待退出
        s_wait(pid, NULL, true);