/* Copyright (C) 2014 J.F.Dockes
* Based on ideas and code contributions from Christian Motz
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "autoconfig.h"
#include "execmd.h"
#include <string>
#include <iostream>
#include <sstream>
#include <unordered_map>
#include "log.h"
#include "safesysstat.h"
#include "safeunistd.h"
#include "safewindows.h"
#include <psapi.h>
#include "smallut.h"
#include "pathut.h"
using namespace std;
//////////////////////////////////////////////
// Helper routines
static void printError(const string& text)
{
DWORD err = GetLastError();
LOGERR(text << " : err: " << err << "\n");
}
/**
Append the given argument to a command line such that
CommandLineToArgvW will return the argument string unchanged.
Arguments in a command line should be separated by spaces; this
function does not add these spaces. The caller must append spaces
between calls.
@param arg Supplies the argument to encode.
@param cmdLine Supplies the command line to which we append
the encoded argument string.
@param force Supplies an indication of whether we should quote
the argument even if it does not contain any characters that
would ordinarily require quoting.
*/
static void argQuote(const string& arg, string& cmdLine, bool force = false)
{
// Don't quote unless we actually need to do so
if (!force && !arg.empty() &&
arg.find_first_of(" \t\n\v\"") == arg.npos) {
cmdLine.append(arg);
} else {
cmdLine.push_back ('"');
for (auto It = arg.begin () ; ; ++It) {
unsigned NumberBackslashes = 0;
while (It != arg.end () && *It == '\\') {
++It;
++NumberBackslashes;
}
if (It == arg.end()) {
// Escape all backslashes, but let the terminating
// double quotation mark we add below be interpreted
// as a metacharacter.
cmdLine.append (NumberBackslashes * 2, '\\');
break;
} else if (*It == L'"') {
// Escape all backslashes and the following
// double quotation mark.
cmdLine.append (NumberBackslashes * 2 + 1, '\\');
cmdLine.push_back (*It);
} else {
// Backslashes aren't special here.
cmdLine.append (NumberBackslashes, '\\');
cmdLine.push_back (*It);
}
}
cmdLine.push_back ('"');
}
}
static string argvToCmdLine(const string& cmd, const vector<string>& args)
{
string cmdline;
argQuote(cmd, cmdline);
for (auto it = args.begin(); it != args.end(); it++) {
cmdline.append(" ");
argQuote(*it, cmdline);
}
return cmdline;
}
// Merge the father environment with the variable specified in m_env
static char *mergeEnvironment(const std::unordered_map<string, string>& addenv)
{
// Parse existing environment.
char *envir = GetEnvironmentStrings();
char *cp0 = envir;
std::unordered_map<string, string> envirmap;
string name, value;
for (char *cp1 = cp0;;cp1++) {
if (*cp1 == '=') {
name = string(cp0, cp1 - cp0);
cp0 = cp1 + 1;
} else if (*cp1 == 0) {
value = string(cp0, cp1 - cp0);
envirmap[name] = value;
LOGDEB1("mergeEnvir: [" << (name) << "] = [" << (value) << "]\n" );
cp0 = cp1 + 1;
if (*cp0 == 0)
break;
}
}
FreeEnvironmentStrings(envir);
// Merge our values
for (auto it = addenv.begin(); it != addenv.end(); it++) {
envirmap[it->first] = it->second;
}
// Create environment block
size_t sz = 0;
for (auto it = envirmap.begin(); it != envirmap.end(); it++) {
sz += it->first.size() + it->second.size() + 2; // =, 0
}
sz++; // final 0
char *nenvir = (char *)malloc(sz);
if (nenvir == 0)
return nenvir;
char *cp = nenvir;
for (auto it = envirmap.begin(); it != envirmap.end(); it++) {
memcpy(cp, it->first.c_str(), it->first.size());
cp += it->first.size();
*cp++ = '=';
memcpy(cp, it->second.c_str(), it->second.size());
cp += it->second.size();
*cp++ = 0;
}
// Final double-zero
*cp++ = 0;
return nenvir;
}
static bool is_exe(const string& path)
{
struct stat st;
if (access(path.c_str(), X_OK) == 0 && stat(path.c_str(), &st) == 0 &&
S_ISREG(st.st_mode)) {
return true;
}
return false;
}
// In mt programs the static vector computations below needs a call
// from main before going mt. This is done by rclinit and saves having
// to take a lock on every call
// Try appending executable suffixes to the base name and see if we
// have something
static bool is_exe_base(const string& path)
{
static vector<string> exts;
if (exts.empty()) {
const char *ep = getenv("PATHEXT");
if (!ep || !*ep) {
ep = ".com;.exe;.bat;.cmd";
}
string eps(ep);
trimstring(eps, ";");
stringToTokens(eps, exts, ";");
}
if (is_exe(path))
return true;
for (auto it = exts.begin(); it != exts.end(); it++) {
if (is_exe(path + *it))
return true;
}
return false;
}
// Parse a PATH spec into a vector<string>
static void make_path_vec(const char *ep, vector<string>& vec)
{
if (ep && *ep) {
string eps(ep);
trimstring(eps, ";");
stringToTokens(eps, vec, ";");
}
vec.insert(vec.begin(), ".\\");
}
static std::string pipeUniqueName(std::string nClass, std::string prefix)
{
std::stringstream uName;
long currCnt;
// PID + multi-thread-protected static counter to be unique
{
static long cnt = 0;
currCnt = InterlockedIncrement(&cnt);
}
DWORD pid = GetCurrentProcessId();
// naming convention
uName << "\\\\.\\" << nClass << "\\";
uName << "pid-" << pid << "-cnt-" << currCnt << "-";
uName << prefix;
return uName.str();
}
enum WaitResult {
Ok, Quit, Timeout
};
static WaitResult Wait(HANDLE hdl, int timeout)
{
//HANDLE hdls[2] = { hdl, eQuit };
HANDLE hdls[1] = { hdl};
LOGDEB1("Wait()\n" );
DWORD res = WaitForMultipleObjects(1, hdls, FALSE, timeout);
if (res == WAIT_OBJECT_0) {
LOGDEB1("Wait: returning Ok\n" );
return Ok;
} else if (res == (WAIT_OBJECT_0 + 1)) {
LOGDEB0("Wait: returning Quit\n" );
return Quit;
} else if (res == WAIT_TIMEOUT) {
LOGDEB0("Wait: returning Timeout\n" );
return Timeout;
}
printError("Wait: WaitForMultipleObjects: unknown, returning Timout\n");
return Timeout;
}
static int getVMMBytes(HANDLE hProcess)
{
PROCESS_MEMORY_COUNTERS pmc;
const int MB = 1024 * 1024;
if (GetProcessMemoryInfo(hProcess, &pmc, sizeof(pmc))) {
LOGDEB2("ExecCmd: getVMMBytes paged Kbs " << (int(pmc.QuotaPagedPoolUsage/1024)) << " non paged " << (int(pmc.QuotaNonPagedPoolUsage/1024)) << " Kbs\n" );
return int(pmc.QuotaPagedPoolUsage /MB +
pmc.QuotaNonPagedPoolUsage / MB);
}
return -1;
}
////////////////////////////////////////////////////////
// ExecCmd:
class ExecCmd::Internal {
public:
Internal(int flags)
: m_advise(0), m_provide(0), m_timeoutMs(1000), m_rlimit_as_mbytes(0),
m_flags(flags) {
reset();
}
std::unordered_map<string, string> m_env;
ExecCmdAdvise *m_advise;
ExecCmdProvide *m_provide;
int m_timeoutMs;
int m_rlimit_as_mbytes;
int m_flags;
// We need buffered I/O for getline. The Unix version uses netcon's
string m_buf; // Buffer. Only used when doing getline()s
size_t m_bufoffs; // Pointer to current 1st byte of useful data
bool m_killRequest;
string m_stderrFile;
HANDLE m_hOutputRead;
HANDLE m_hInputWrite;
OVERLAPPED m_oOutputRead;
OVERLAPPED m_oInputWrite;
PROCESS_INFORMATION m_piProcInfo;
// Reset internal state indicators. Any resources should have been
// previously freed.
void reset() {
m_buf.resize(0);
m_bufoffs = 0;
m_stderrFile.erase();
m_killRequest = false;
m_hOutputRead = NULL;
m_hInputWrite = NULL;
memset(&m_oOutputRead, 0, sizeof(m_oOutputRead));
memset(&m_oInputWrite, 0, sizeof(m_oInputWrite));
ZeroMemory(&m_piProcInfo, sizeof(PROCESS_INFORMATION));
}
bool preparePipes(bool has_input, HANDLE *hChildInput,
bool has_output, HANDLE *hChildOutput,
HANDLE *hChildError);
bool tooBig();
};
// Sending a break to a subprocess is only possible if we share the
// same console We temporarily ignore breaks, attach to the Console,
// send the break, and restore normal break processing
static bool sendIntr(int pid)
{
LOGDEB("execmd_w: sendIntr -> " << (pid) << "\n" );
bool needDetach = false;
if (GetConsoleWindow() == NULL) {
needDetach = true;
LOGDEB("execmd_w: sendIntr attaching console\n" );
if (!AttachConsole((unsigned int) pid)) {
int err = GetLastError();
LOGERR("execmd_w: sendIntr: AttachConsole failed: " << (err) << "\n" );
return false;
}
}
#if 0
// Would need to do this for sending to all processes on this console
// Disable Ctrl-C handling for our program
if (!SetConsoleCtrlHandler(NULL, true)) {
int err = GetLastError();
LOGERR("execmd_w:sendIntr:SetCons.Ctl.Hndlr.(NULL, true) failed: " << (err) << "\n" );
return false;
}
#endif
// Note: things don't work with CTRL_C (process not advised, sometimes
// stays apparently blocked), no idea why
bool ret = GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT, pid);
if (!ret) {
int err = GetLastError();
LOGERR("execmd_w:sendIntr:Gen.Cons.CtrlEvent failed: " << (err) << "\n" );
}
#if 0
// Restore Ctrl-C handling for our program
SetConsoleCtrlHandler(NULL, false);
#endif
if (needDetach) {
LOGDEB("execmd_w: sendIntr detaching console\n" );
if (!FreeConsole()) {
int err = GetLastError();
LOGERR("execmd_w: sendIntr: FreeConsole failed: " << (err) << "\n" );
}
}
return ret;
}
// ExecCmd resource releaser class. Using a separate object makes it
// easier that resources are released under all circumstances,
// esp. exceptions
class ExecCmdRsrc {
public:
ExecCmdRsrc(ExecCmd::Internal *parent)
: m_parent(parent), m_active(true) {
}
void inactivate() {
m_active = false;
}
~ExecCmdRsrc() {
if (!m_active || !m_parent)
return;
LOGDEB1("~ExecCmdRsrc: working. mypid: " << ((int)getpid()) << "\n" );
if (m_parent->m_hOutputRead)
CloseHandle(m_parent->m_hOutputRead);
if (m_parent->m_hInputWrite)
CloseHandle(m_parent->m_hInputWrite);
if (m_parent->m_oOutputRead.hEvent)
CloseHandle(m_parent->m_oOutputRead.hEvent);
if (m_parent->m_oInputWrite.hEvent)
CloseHandle(m_parent->m_oInputWrite.hEvent);
if (m_parent->m_piProcInfo.hProcess) {
BOOL bSuccess = sendIntr(m_parent->m_piProcInfo.dwProcessId);
if (bSuccess) {
// Give it a chance, then terminate
for (int i = 0; i < 3; i++) {
WaitResult res = Wait(m_parent->m_piProcInfo.hProcess,
i == 0 ? 5 : (i == 1 ? 100 : 2000));
switch (res) {
case Ok:
case Quit:
goto breakloop;
case Timeout:
if (i == 2) {
TerminateProcess(m_parent->m_piProcInfo.hProcess,
0xffff);
}
}
}
} else {
TerminateProcess(m_parent->m_piProcInfo.hProcess,
0xffff);
}
breakloop:
CloseHandle(m_parent->m_piProcInfo.hProcess);
}
if (m_parent->m_piProcInfo.hThread)
CloseHandle(m_parent->m_piProcInfo.hThread);
m_parent->reset();
}
private:
ExecCmd::Internal *m_parent;
bool m_active;
};
ExecCmd::ExecCmd(int flags)
{
m = new Internal(flags);
if (m) {
m->reset();
}
}
ExecCmd::~ExecCmd()
{
if (m) {
ExecCmdRsrc(this->m);
delete m;
}
}
// This does nothing under windows, but defining it avoids ifdefs in multiple
// places
void ExecCmd::useVfork(bool)
{
}
bool ExecCmd::which(const string& cmd, string& exe, const char* path)
{
static vector<string> s_pathelts;
vector<string> pathelts;
vector<string> *pep;
if (path) {
make_path_vec(path, pathelts);
pep = &pathelts;
} else {
if (s_pathelts.empty()) {
const char *ep = getenv("PATH");
make_path_vec(ep, s_pathelts);
}
pep = &s_pathelts;
}
if (path_isabsolute(cmd)) {
if (is_exe_base(cmd)) {
exe = cmd;
return true;
}
exe.clear();
return false;
}
for (auto it = pep->begin(); it != pep->end(); it++) {
exe = path_cat(*it, cmd);
if (is_exe_base(exe)) {
return true;
}
}
exe.clear();
return false;
}
void ExecCmd::setAdvise(ExecCmdAdvise *adv)
{
m->m_advise = adv;
}
void ExecCmd::setProvide(ExecCmdProvide *p)
{
m->m_provide = p;
}
void ExecCmd::setTimeout(int mS)
{
if (mS > 30) {
m->m_timeoutMs = mS;
}
}
void ExecCmd::setStderr(const std::string& stderrFile)
{
m->m_stderrFile = stderrFile;
}
pid_t ExecCmd::getChildPid()
{
return m->m_piProcInfo.dwProcessId;
}
void ExecCmd::setKill()
{
m->m_killRequest = true;
}
void ExecCmd::zapChild()
{
setKill();
(void)wait();
}
bool ExecCmd::requestChildExit()
{
if (m->m_piProcInfo.hProcess) {
return sendIntr(m->m_piProcInfo.dwProcessId);
}
return false;
}
void ExecCmd::putenv(const string &envassign)
{
vector<string> v;
stringToTokens(envassign, v, "=");
if (v.size() == 2) {
m->m_env[v[0]] = v[1];
}
}
void ExecCmd::putenv(const string &name, const string& value)
{
m->m_env[name] = value;
}
void ExecCmd::setrlimit_as(int mbytes)
{
m->m_rlimit_as_mbytes = mbytes;
}
bool ExecCmd::Internal::tooBig()
{
if (m_rlimit_as_mbytes <= 0)
return false;
int mbytes = getVMMBytes(m_piProcInfo.hProcess);
if (mbytes > m_rlimit_as_mbytes) {
LOGINFO("ExecCmd:: process mbytes " << (mbytes) << " > set limit " << (m_rlimit_as_mbytes) << "\n" );
m_killRequest = true;
return true;
}
return false;
}
bool ExecCmd::Internal::preparePipes(bool has_input,HANDLE *hChildInput,
bool has_output, HANDLE *hChildOutput,
HANDLE *hChildError)
{
// Note: our caller is responsible for ensuring that we start with
// a clean state, and for freeing class resources in case of
// error. We just manage the local ones.
HANDLE hOutputWrite = NULL;
HANDLE hErrorWrite = NULL;
HANDLE hInputRead = NULL;
// manual reset event
m_oOutputRead.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (m_oOutputRead.hEvent == INVALID_HANDLE_VALUE) {
LOGERR("ExecCmd::preparePipes: CreateEvent failed\n" );
goto errout;
}
// manual reset event
m_oInputWrite.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (m_oInputWrite.hEvent == INVALID_HANDLE_VALUE) {
LOGERR("ExecCmd::preparePipes: CreateEvent failed\n" );
goto errout;
}
SECURITY_ATTRIBUTES sa;
// Set up the security attributes struct.
sa.nLength = sizeof(SECURITY_ATTRIBUTES);
sa.bInheritHandle = TRUE; // this is the critical bit
sa.lpSecurityDescriptor = NULL;
if (has_output) {
// src for this code: https://www.daniweb.com/software-development/cpp/threads/295780/using-named-pipes-with-asynchronous-io-redirection-to-winapi
// ONLY IMPORTANT CHANGE
// set inheritance flag to TRUE in CreateProcess
// you need this for the client to inherit the handles
// Create the child output named pipe.
// This creates a non-inheritable, one-way handle for the server to read
string pipeName = pipeUniqueName("pipe", "output");
sa.bInheritHandle = FALSE;
m_hOutputRead = CreateNamedPipeA(
pipeName.c_str(),
PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED,
PIPE_WAIT,
1, 4096, 4096, 0, &sa);
if (m_hOutputRead == INVALID_HANDLE_VALUE) {
printError("preparePipes: CreateNamedPipe(outputR)");
goto errout;
}
// However, the client can not use an inbound server handle.
// Client needs a write-only, outgoing handle.
// So, you create another handle to the same named pipe, only
// write-only. Again, must be created with the inheritable
// attribute, and the options are important.
// use CreateFile to open a new handle to the existing pipe...
sa.bInheritHandle = TRUE;
hOutputWrite = CreateFile(
pipeName.c_str(),
FILE_WRITE_DATA | SYNCHRONIZE,
0, &sa, OPEN_EXISTING, // very important flag!
FILE_ATTRIBUTE_NORMAL, 0 // no template file for OPEN_EXISTING
);
if (hOutputWrite == INVALID_HANDLE_VALUE) {
printError("preparePipes: CreateFile(outputWrite)");
goto errout;
}
} else {
// Not using child output. Let the child have our standard output.
HANDLE hstd = GetStdHandle(STD_OUTPUT_HANDLE);
if (hstd == INVALID_HANDLE_VALUE) {
printError("preparePipes: GetStdHandle(stdout)");
goto errout;
}
if (!DuplicateHandle(GetCurrentProcess(), hstd,
GetCurrentProcess(), &hOutputWrite,
0, TRUE,
DUPLICATE_SAME_ACCESS)) {
printError("preparePipes: DuplicateHandle(stdout)");
// This occurs when the parent process is a GUI app. Ignoring the error works, but
// not too sure this is the right approach. Maybe look a bit more at:
// https://support.microsoft.com/en-us/kb/190351
//goto errout;
}
}
if (has_input) {
// now same procedure for input pipe
sa.bInheritHandle = FALSE;
string pipeName = pipeUniqueName("pipe", "input");
m_hInputWrite = CreateNamedPipeA(
pipeName.c_str(),
PIPE_ACCESS_OUTBOUND | FILE_FLAG_OVERLAPPED,
PIPE_WAIT,
1, 4096, 4096, 0, &sa);
if (m_hInputWrite == INVALID_HANDLE_VALUE) {
printError("preparePipes: CreateNamedPipe(inputW)");
goto errout;
}
sa.bInheritHandle = TRUE;
hInputRead = CreateFile(
pipeName.c_str(),
FILE_READ_DATA | SYNCHRONIZE,
0, &sa, OPEN_EXISTING, // very important flag!
FILE_ATTRIBUTE_NORMAL, 0 // no template file for OPEN_EXISTING
);
if (hInputRead == INVALID_HANDLE_VALUE) {
printError("preparePipes: CreateFile(inputRead)");
goto errout;
}
} else {
// Let the child inherit our standard input
HANDLE hstd = GetStdHandle(STD_INPUT_HANDLE);
if (hstd == INVALID_HANDLE_VALUE) {
printError("preparePipes: GetStdHandle(stdin)");
goto errout;
}
if (!DuplicateHandle(GetCurrentProcess(), hstd,
GetCurrentProcess(), &hInputRead,
0, TRUE,
DUPLICATE_SAME_ACCESS)) {
printError("preparePipes: DuplicateHandle(stdin)");
//goto errout;
}
}
// Stderr: output to file or inherit. We don't support the file thing
// for the moment
if (false && !m_stderrFile.empty()) {
// Open the file set up the child handle: TBD
printError("preparePipes: m_stderrFile not empty");
} else {
// Let the child inherit our standard input
HANDLE hstd = GetStdHandle(STD_ERROR_HANDLE);
if (hstd == INVALID_HANDLE_VALUE) {
printError("preparePipes: GetStdHandle(stderr)");
goto errout;
}
if (!DuplicateHandle(GetCurrentProcess(), hstd,
GetCurrentProcess(), &hErrorWrite,
0, TRUE,
DUPLICATE_SAME_ACCESS)) {
printError("preparePipes: DuplicateHandle(stderr)");
//goto errout;
}
}
*hChildInput = hInputRead;
*hChildOutput = hOutputWrite;
*hChildError = hErrorWrite;
return true;
errout:
if (hOutputWrite)
CloseHandle(hOutputWrite);
if (hInputRead)
CloseHandle(hInputRead);
if (hErrorWrite)
CloseHandle(hErrorWrite);
return false;
}
// Create a child process
int ExecCmd::startExec(const string &cmd, const vector<string>& args,
bool has_input, bool has_output)
{
{ // Debug and logging
string command = cmd + " ";
for (vector<string>::const_iterator it = args.begin();
it != args.end(); it++) {
command += "{" + *it + "} ";
}
LOGDEB("ExecCmd::startExec: (" << (has_input) << "|" << (has_output) << ") " << (command) << "\n" );
}
// What if we're called twice ? First make sure we're clean
{
ExecCmdRsrc(this->m);
}
// Arm clean up. This will be disabled before a success return.
ExecCmdRsrc cleaner(this->m);
string cmdline = argvToCmdLine(cmd, args);
HANDLE hInputRead;
HANDLE hOutputWrite;
HANDLE hErrorWrite;
if (!m->preparePipes(has_input, &hInputRead, has_output,
&hOutputWrite, &hErrorWrite)) {
LOGERR("ExecCmd::startExec: preparePipes failed\n" );
return false;
}
STARTUPINFO siStartInfo;
BOOL bSuccess = FALSE;
// Set up members of the PROCESS_INFORMATION structure.
ZeroMemory(&m->m_piProcInfo, sizeof(PROCESS_INFORMATION));
// Set up members of the STARTUPINFO structure.
// This structure specifies the STDIN and STDOUT handles for redirection.
ZeroMemory(&siStartInfo, sizeof(STARTUPINFO));
siStartInfo.cb = sizeof(STARTUPINFO);
if (m->m_flags & EXF_SHOWWINDOW) {
siStartInfo.dwFlags |= STARTF_USESTDHANDLES;
if (m->m_flags & EXF_MAXIMIZED) {
siStartInfo.dwFlags |= STARTF_USESHOWWINDOW;
siStartInfo.wShowWindow = SW_SHOWMAXIMIZED;
}
} else {
siStartInfo.dwFlags |= STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
// This is to hide the console when starting a cmd line command from
// the GUI. Also note STARTF_USESHOWWINDOW above
siStartInfo.wShowWindow = SW_HIDE;
}
siStartInfo.hStdOutput = hOutputWrite;
siStartInfo.hStdInput = hInputRead;
siStartInfo.hStdError = hErrorWrite;
char *envir = mergeEnvironment(m->m_env);
// Create the child process.
// Need a writable buffer for the command line, for some reason.
LOGDEB1("ExecCmd:startExec: cmdline [" << (cmdline) << "]\n" );
LPSTR buf = (LPSTR)malloc(cmdline.size() + 1);
memcpy(buf, cmdline.c_str(), cmdline.size());
buf[cmdline.size()] = 0;
bSuccess = CreateProcess(NULL,
buf, // command line
NULL, // process security attributes
NULL, // primary thread security attrs
TRUE, // handles are inherited
CREATE_NEW_PROCESS_GROUP, // creation flags
envir, // Merged environment
NULL, // use parent's current directory
&siStartInfo, // STARTUPINFO pointer
&m->m_piProcInfo); // PROCESS_INFORMATION
if (!bSuccess) {
printError("ExecCmd::doexec: CreateProcess");
}
free(envir);
free(buf);
// Close child-side handles else we'll never see eofs
if (!CloseHandle(hOutputWrite))
printError("CloseHandle");
if (!CloseHandle(hInputRead))
printError("CloseHandle");
if (!CloseHandle(hErrorWrite))
printError("CloseHandle");
if (bSuccess) {
cleaner.inactivate();
}
return bSuccess;
}
// Send data to the child.
int ExecCmd::send(const string& data)
{
LOGDEB2("ExecCmd::send: cnt " << (int(data.size())) << "\n" );
BOOL bSuccess = WriteFile(m->m_hInputWrite, data.c_str(),
(DWORD)data.size(), NULL, &m->m_oInputWrite);
DWORD err = GetLastError();
// TODO: some more decision, either the operation completes immediately
// and we get success, or it is started (which is indicated by no success)
// and ERROR_IO_PENDING
// in the first case bytes read/written parameter can be used directly
if (!bSuccess && err != ERROR_IO_PENDING) {
LOGERR("ExecCmd::send: WriteFile: got err " << (err) << "\n" );
return -1;
}
WaitResult waitRes = Wait(m->m_oInputWrite.hEvent, m->m_timeoutMs);
DWORD dwWritten;
if (waitRes == Ok) {
if (!GetOverlappedResult(m->m_hInputWrite,
&m->m_oInputWrite, &dwWritten, TRUE)) {
err = GetLastError();
LOGERR("ExecCmd::send: GetOverLappedResult: err " << (err) << "\n" );
return -1;
}
} else if (waitRes == Quit) {
printError("ExecCmd::send: got Quit");
if (!CancelIo(m->m_hInputWrite)) {
printError("CancelIo");
}
return -1;
} else if (waitRes == Timeout) {
printError("ExecCmd::send: got Timeout");
if (!CancelIo(m->m_hInputWrite)) {
printError("CancelIo");
}
return -1;
}
LOGDEB2("ExecCmd::send: returning " << (int(dwWritten)) << "\n" );
return dwWritten;
}
#ifndef MIN
#define MIN(A,B) ((A)<(B)?(A):(B))
#endif
// Read output from the child process's pipe for STDOUT
// and write to cout in this programme
// Stop when there is no more data.
// @arg cnt count to read, -1 means read to end of data.
// 0 means read whatever comes back on the first read;
int ExecCmd::receive(string& data, int cnt)
{
LOGDEB1("ExecCmd::receive: cnt " << (cnt) << "\n" );
int totread = 0;
// If there is buffered data, use it (remains from a previous getline())
if (m->m_bufoffs < m->m_buf.size()) {
int bufcnt = int(m->m_buf.size() - m->m_bufoffs);
int toread = (cnt > 0) ? MIN(cnt, bufcnt) : bufcnt;
data.append(m->m_buf, m->m_bufoffs, toread);
m->m_bufoffs += toread;
totread += toread;
if (cnt == 0 || (cnt > 0 && totread == cnt)) {
return cnt;
}
}
while (true) {
const int BUFSIZE = 4096;
CHAR chBuf[BUFSIZE];
int toread = cnt > 0 ? MIN(cnt - totread, BUFSIZE) : BUFSIZE;
BOOL bSuccess = ReadFile(m->m_hOutputRead, chBuf, toread,
NULL, &m->m_oOutputRead);
DWORD err = GetLastError();
LOGDEB1("receive: ReadFile: success " << (int(bSuccess)) << " err " << (int(err)) << "\n" );
if (!bSuccess && err != ERROR_IO_PENDING) {
if (err != ERROR_BROKEN_PIPE)
LOGERR("ExecCmd::receive: ReadFile error: " << (int(err)) << "\n" );
break;
}
waitagain:
WaitResult waitRes = Wait(m->m_oOutputRead.hEvent, m->m_timeoutMs);
if (waitRes == Ok) {
DWORD dwRead;
if (!GetOverlappedResult(m->m_hOutputRead, &m->m_oOutputRead,
&dwRead, TRUE)) {
err = GetLastError();
if (err && err != ERROR_BROKEN_PIPE) {
LOGERR("ExecCmd::recv:GetOverlappedResult: err " << (err) << "\n" );
return -1;
}
}
if (dwRead > 0) {
totread += dwRead;
data.append(chBuf, dwRead);
if (m->m_advise)
m->m_advise->newData(dwRead);
LOGDEB1("ExecCmd::recv: ReadFile: " << (int(dwRead)) << " bytes\n" );
}
} else if (waitRes == Quit) {
if (!CancelIo(m->m_hOutputRead)) {
printError("CancelIo");
}
break;
} else if (waitRes == Timeout) {
LOGDEB0("ExecCmd::receive: timeout (" << (m->m_timeoutMs) << " mS)\n" );
if (m->tooBig()) {
if (!CancelIo(m->m_hOutputRead)) {
printError("CancelIo");
}
return -1;
}
// We only want to cancel if m_advise says so here.
if (m->m_advise) {
try {
m->m_advise->newData(0);
} catch (...) {
if (!CancelIo(m->m_hOutputRead)) {
printError("CancelIo");
}
throw;
}
}
if (m->m_killRequest) {
LOGINFO("ExecCmd::doexec: cancel request\n" );
if (!CancelIo(m->m_hOutputRead)) {
printError("CancelIo");
}
break;
}
goto waitagain;
}
if ((cnt == 0 && totread > 0) || (cnt > 0 && totread == cnt))
break;
}
LOGDEB1("ExecCmd::receive: returning " << (totread) << " bytes\n" );
return totread;
}
int ExecCmd::getline(string& data)
{
LOGDEB2("ExecCmd::getline: cnt " << (cnt) << ", timeo " << (timeo) << "\n" );
data.erase();
if (m->m_buf.empty()) {
m->m_buf.reserve(4096);
m->m_bufoffs = 0;
}
for (;;) {
// Transfer from buffer. Have to take a lot of care to keep counts and
// pointers consistant in all end cases
int nn = int(m->m_buf.size() - m->m_bufoffs);
bool foundnl = false;
for (; nn > 0;) {
nn--;
char c = m->m_buf[m->m_bufoffs++];
if (c == '\r')
continue;
data += c;
if (c == '\n') {
foundnl = true;
break;
}
}
if (foundnl) {
LOGDEB2("ExecCmd::getline: ret: [" << (data) << "]\n" );
return int(data.size());
}
// Read more
m->m_buf.erase();
if (receive(m->m_buf, 0) < 0) {
return -1;
}
if (m->m_buf.empty()) {
LOGDEB("ExecCmd::getline: eof? ret: [" << (data) << "]\n" );
return int(data.size());
}
m->m_bufoffs = 0;
}
//??
return -1;
}
int ExecCmd::wait()
{
// If killRequest was set, we don't perform the normal
// wait. cleaner will kill the child.
ExecCmdRsrc cleaner(this->m);
DWORD exit_code = -1;
if (!m->m_killRequest && m->m_piProcInfo.hProcess) {
// Wait until child process exits.
while (WaitForSingleObject(m->m_piProcInfo.hProcess, m->m_timeoutMs)
== WAIT_TIMEOUT) {
LOGDEB("ExecCmd::wait: timeout (ok)\n" );
if (m->m_advise) {
m->m_advise->newData(0);
}
if (m->tooBig()) {
// Let cleaner work to kill the child
m->m_killRequest = true;
return -1;
}
}
exit_code = 0;
GetExitCodeProcess(m->m_piProcInfo.hProcess, &exit_code);
// Clean up, here to avoid cleaner trying to kill the now
// inexistant process.
CloseHandle(m->m_piProcInfo.hProcess);
m->m_piProcInfo.hProcess = NULL;
if (m->m_piProcInfo.hThread) {
CloseHandle(m->m_piProcInfo.hThread);
m->m_piProcInfo.hThread = NULL;
}
}
return (int)exit_code;
}
bool ExecCmd::maybereap(int *status)
{
ExecCmdRsrc e(this->m);
*status = -1;
if (m->m_piProcInfo.hProcess == NULL) {
// Already waited for ??
return true;
}
WaitResult res = Wait(m->m_piProcInfo.hProcess, 1);
DWORD exit_code = -1;
switch (res) {
case Ok:
exit_code = 0;
GetExitCodeProcess(m->m_piProcInfo.hProcess, &exit_code);
*status = (int)exit_code;
CloseHandle(m->m_piProcInfo.hProcess);
m->m_piProcInfo.hProcess = NULL;
if (m->m_piProcInfo.hThread) {
CloseHandle(m->m_piProcInfo.hThread);
m->m_piProcInfo.hThread = NULL;
}
return true;
default:
e.inactivate();
return false;
}
}
// Static
bool ExecCmd::backtick(const vector<string> cmd, string& out)
{
vector<string>::const_iterator it = cmd.begin();
it++;
vector<string> args(it, cmd.end());
ExecCmd mexec;
int status = mexec.doexec(*cmd.begin(), args, 0, &out);
return status == 0;
}
int ExecCmd::doexec(const string &cmd, const vector<string>& args,
const string *input, string *output)
{
if (input && output) {
LOGERR("ExecCmd::doexec: can't do both input and output\n" );
return -1;
}
// The assumption is that the state is clean when this method
// returns. Have a cleaner ready in case we return without
// calling wait() e.g. if an exception is raised in receive()
ExecCmdRsrc cleaner(this->m);
if (startExec(cmd, args, input != 0, output != 0) < 0) {
return -1;
}
if (input) {
if (!input->empty()) {
if (send(*input) != (int)input->size()) {
LOGERR("ExecCmd::doexec: send failed\n" );
CloseHandle(m->m_hInputWrite);
m->m_hInputWrite = NULL;
return -1;
}
}
if (m->m_provide) {
for (;;) {
m->m_provide->newData();
if (input->empty()) {
CloseHandle(m->m_hInputWrite);
m->m_hInputWrite = NULL;
break;
}
if (send(*input) != (int)input->size()) {
LOGERR("ExecCmd::doexec: send failed\n" );
CloseHandle(m->m_hInputWrite);
m->m_hInputWrite = NULL;
break;
}
}
}
} else if (output) {
receive(*output);
}
cleaner.inactivate();
return wait();
}