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extras/piped_proc.cpp

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+/* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "stdafx.h"
+#include "piped_proc.h"
+#include "Logs.h"
+
+#ifdef __unix__
+piped_proc::piped_proc(std::string cmd)
+{
+	file = popen(cmd.c_str(), "r");
+}
+
+piped_proc::~piped_proc()
+{
+	if (file)
+		pclose(file);
+}
+
+size_t piped_proc::read(unsigned char *buf, size_t len)
+{
+	if (!file)
+		return 0;
+
+	return fread(buf, 1, len, file);
+}
+#elif _WIN32
+piped_proc::piped_proc(std::string cmd)
+{
+	PROCESS_INFORMATION process;
+	STARTUPINFO siStartInfo;
+	SECURITY_ATTRIBUTES saAttr;
+
+	memset(&process, 0, sizeof(PROCESS_INFORMATION));
+	memset(&siStartInfo, 0, sizeof(STARTUPINFO));
+	memset(&saAttr, 0, sizeof(SECURITY_ATTRIBUTES));
+
+	saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
+	saAttr.bInheritHandle = TRUE;
+	saAttr.lpSecurityDescriptor = NULL;
+
+	if (!CreatePipe(&pipe_rd, &pipe_wr, &saAttr, 0)) {
+		ErrorLog("piped_proc: CreatePipe failed!");
+		return;
+	}
+
+	if (!SetHandleInformation(pipe_rd, HANDLE_FLAG_INHERIT, 0)) {
+		ErrorLog("piped_proc: SetHandleInformation failed!");
+		return;
+	}
+
+	siStartInfo.cb = sizeof(STARTUPINFO);
+	siStartInfo.hStdError = GetStdHandle(STD_ERROR_HANDLE);
+	siStartInfo.hStdOutput = pipe_wr;
+	siStartInfo.dwFlags |= STARTF_USESTDHANDLES;
+
+	if (!CreateProcessA(NULL, (char*)cmd.c_str(), NULL, NULL, TRUE, 0, NULL, NULL, &siStartInfo, &process)) {
+		ErrorLog("piped_proc: CreateProcess failed!");
+		return;
+	}
+
+	if (process.hProcess)
+		CloseHandle(process.hProcess);
+	if (process.hThread)
+		CloseHandle(process.hThread);
+}
+
+piped_proc::~piped_proc()
+{
+	if (pipe_wr)
+		CloseHandle(pipe_wr);
+	if (pipe_rd)
+		CloseHandle(pipe_rd);
+}
+
+size_t piped_proc::read(unsigned char *buf, size_t len)
+{
+	if (!pipe_rd)
+		return 0;
+
+	DWORD read = 0;
+	BOOL ret = ReadFile(pipe_rd, buf, len, &read, NULL);
+
+	return read;
+}
+#endif

extras/piped_proc.h

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+/* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#pragma once
+
+#ifdef __unix__
+#include <cstdio>
+#elif _WIN32
+#include "winheaders.h"
+#endif
+#include <string>
+
+class piped_proc
+{
+private:
+#ifdef __unix__
+FILE *file = nullptr;
+#elif _WIN32
+HANDLE pipe_rd = nullptr;
+HANDLE pipe_wr = nullptr;
+#endif
+
+public:
+    piped_proc(std::string cmd);
+	size_t read(unsigned char *buf, size_t len);
+	~piped_proc();
+};