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livetrax/libs/pbd/system_exec.cc
Robin Gareus 0e570d15ae
Amend 3a7ea6b, do not kill child after 10 sec w/o output
This fixes video-timeline issues (harvid has no output), as well
as ALSA device reservation and xjadeo (when idle).
2021-06-08 23:23:31 +02:00

914 lines
19 KiB
C++

/*
* Copyright (C) 2005-2008 Lennart Poettering
* Copyright (C) 2010-2019 Robin Gareus <robin@gareus.org>
* Copyright (C) 2013-2014 Colin Fletcher <colin.m.fletcher@googlemail.com>
* Copyright (C) 2014-2015 Paul Davis <paul@linuxaudiosystems.com>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <algorithm>
#include <assert.h>
#ifndef COMPILER_MSVC
#include <dirent.h>
#endif
#ifdef PLATFORM_WINDOWS
#include <windows.h>
#else
#include <poll.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/resource.h>
#endif
#include <glibmm/miscutils.h>
#include "pbd/file_utils.h"
#include "pbd/search_path.h"
#include "pbd/pthread_utils.h"
#include "pbd/system_exec.h"
using namespace std;
using namespace PBD;
static void * interposer_thread (void *arg);
#ifndef PLATFORM_WINDOWS /* POSIX Process only */
static void close_fd (int& fd) { if (fd >= 0) ::close (fd); fd = -1; }
#endif
void
SystemExec::init ()
{
pthread_mutex_init (&write_lock, NULL);
thread_active = false;
pid = 0;
pin[1] = -1;
nicelevel = 0;
envp = NULL;
#ifdef PLATFORM_WINDOWS
stdinP[0] = stdinP[1] = INVALID_HANDLE_VALUE;
stdoutP[0] = stdoutP[1] = INVALID_HANDLE_VALUE;
stderrP[0] = stderrP[1] = INVALID_HANDLE_VALUE;
w_args = NULL;
#else
argx = NULL;
#endif
}
SystemExec::SystemExec (std::string c, std::string a)
: cmd(c)
{
init ();
argp = NULL;
make_envp();
make_argp(a);
}
SystemExec::SystemExec (std::string c, char **a)
: cmd(c) , argp(a)
{
init ();
#ifdef PLATFORM_WINDOWS
make_wargs(a);
#endif
make_envp();
}
SystemExec::SystemExec (std::string command, const std::map<char, std::string> subs)
{
init ();
make_argp_escaped(command, subs);
#ifdef PLATFORM_WINDOWS
if (argp[0] && strlen (argp[0]) > 0) {
std::string wa = argp[0];
// only add quotes to command if required..
if (argp[0][0] != '"'
&& argp[0][strlen(argp[0])-1] != '"'
&& strchr(argp[0], ' ')) {
wa = "\"";
wa += argp[0];
wa += "\"";
}
// ...but always quote all args
for (int i = 1; argp[i]; ++i) {
std::string tmp (argp[i]);
size_t start_pos = 0;
while ((start_pos = tmp.find("\"", start_pos)) != std::string::npos) {
tmp.replace (start_pos, 1, "\\\"");
start_pos += 2;
}
wa += " \"";
wa += tmp;
wa += '"';
}
w_args = strdup(wa.c_str());
}
#else
if (find_file (Searchpath (Glib::getenv ("PATH")), argp[0], cmd)) {
// argp[0] exists in $PATH` - set it to the actual path where it was found
free (argp[0]);
argp[0] = strdup(cmd.c_str ());
}
// else argp[0] not found in path - leave it as-is, it might be an absolute path
// Glib::find_program_in_path () is only available in Glib >= 2.28
// cmd = Glib::find_program_in_path (argp[0]);
#endif
make_envp();
}
char*
SystemExec::format_key_value_parameter (std::string key, std::string value)
{
size_t start_pos = 0;
std::string v1 = value;
while((start_pos = v1.find_first_not_of(
"abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789(),.\"'",
start_pos)) != std::string::npos)
{
v1.replace(start_pos, 1, "_");
start_pos += 1;
}
#ifdef PLATFORM_WINDOWS
/* SystemExec::make_wargs() adds quotes around the complete argument
* windows uses CreateProcess() with a parameter string
* (and not an array list of separate arguments like Unix)
* so quotes need to be escaped.
*/
start_pos = 0;
while((start_pos = v1.find("\"", start_pos)) != std::string::npos) {
v1.replace(start_pos, 1, "\\\"");
start_pos += 2;
}
#endif
size_t len = key.length() + v1.length() + 2;
char *mds = (char*) calloc(len, sizeof(char));
snprintf(mds, len, "%s=%s", key.c_str(), v1.c_str());
return mds;
}
void
SystemExec::make_argp_escaped (std::string command, const std::map<char, std::string> subs)
{
int inquotes = 0;
int n = 0;
size_t i = 0;
std::string arg = "";
argp = (char**) malloc (sizeof(char*));
for (i = 0; i <= command.length(); i++) { // include terminating '\0'
char c = command.c_str()[i];
if (inquotes) {
if (c == '"') {
inquotes = 0;
} else {
// still in quotes - just copy
arg += c;
}
} else switch (c) {
case '%' :
c = command.c_str()[++i];
if (c == '%' || c == '\0') {
// "%%", "%" at end-of-string => "%"
arg += '%';
} else {
// search subs for string to substitute for char
std::map<char, std::string>::const_iterator s = subs.find(c);
if (s != subs.end()) {
// found substitution
arg += s->second;
} else {
// not a valid substitution, just copy
arg += '%';
arg += c;
}
}
break;
case '\\':
c = command.c_str()[++i];
switch (c) {
case ' ' :
case '"' : arg += c; break; // "\\", "\" at end-of-string => "\"
case '\0':
case '\\': arg += '\\'; break;
default : arg += '\\'; arg += c; break;
}
break;
case '"' :
inquotes = 1;
break;
case ' ' :
case '\t':
case '\0':
if (arg.length() > 0) {
// if there wasn't already a space or tab, start a new parameter
argp = (char **) realloc(argp, (n + 2) * sizeof(char *));
argp[n++] = strdup (arg.c_str());
arg = "";
}
break;
default :
arg += c;
break;
}
}
argp[n] = NULL;
}
SystemExec::~SystemExec ()
{
terminate ();
if (envp) {
for (int i = 0; envp[i]; ++i) {
free (envp[i]);
}
free (envp);
}
if (argp) {
for (int i = 0; argp[i]; ++i) {
free (argp[i]);
}
free (argp);
}
#ifdef PLATFORM_WINDOWS
if (w_args) free(w_args);
#else
if (argx) {
/* argx[0 .. 8] are fixed parameters to vfork-exec-wrapper */
for (int i = 0; i < 9; ++i) {
free (argx[i]);
}
free (argx);
}
#endif
pthread_mutex_destroy(&write_lock);
}
static void*
interposer_thread (void *arg) {
SystemExec *sex = static_cast<SystemExec *>(arg);
pthread_set_name ("ExecStdOut");
sex->output_interposer();
pthread_exit(0);
return 0;
}
string
SystemExec::to_s () const
{
#ifdef PLATFORM_WINDOWS
return string (w_args ? w_args : "");
#else
stringstream out;
if (argp) {
for (int i = 0; argp[i]; ++i) {
out << argp[i] << " ";
}
}
return out.str();
#endif
}
size_t
SystemExec::write_to_stdin (std::string const& d, size_t len)
{
const char *data = d.c_str();
if (len == 0) {
len = d.length();
}
return write_to_stdin ((const void*)data, len);
}
size_t
SystemExec::write_to_stdin (const char* data, size_t len)
{
if (len == 0) {
len = strlen (data);
}
return write_to_stdin ((const void*)data, len);
}
#ifdef PLATFORM_WINDOWS /* Windows Process */
/* HELPER FUNCTIONS */
static void
create_pipe (HANDLE *pipe, bool in)
{
SECURITY_ATTRIBUTES secAtt = { sizeof(SECURITY_ATTRIBUTES), NULL, TRUE };
HANDLE tmpHandle;
if (in) {
if (!CreatePipe(&pipe[0], &tmpHandle, &secAtt, 1024 * 1024)) return;
if (!DuplicateHandle(GetCurrentProcess(), tmpHandle, GetCurrentProcess(), &pipe[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) return;
} else {
if (!CreatePipe(&tmpHandle, &pipe[1], &secAtt, 1024 * 1024)) return;
if (!DuplicateHandle(GetCurrentProcess(), tmpHandle, GetCurrentProcess(), &pipe[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) return;
}
CloseHandle(tmpHandle);
}
static void
destroy_pipe (HANDLE pipe[2])
{
if (pipe[0] != INVALID_HANDLE_VALUE) {
CloseHandle(pipe[0]);
pipe[0] = INVALID_HANDLE_VALUE;
}
if (pipe[1] != INVALID_HANDLE_VALUE) {
CloseHandle(pipe[1]);
pipe[1] = INVALID_HANDLE_VALUE;
}
}
static BOOL
CALLBACK my_terminateApp(HWND hwnd, LPARAM procId)
{
DWORD currentProcId = 0;
GetWindowThreadProcessId(hwnd, &currentProcId);
if (currentProcId == (DWORD)procId)
PostMessage(hwnd, WM_CLOSE, 0, 0);
return TRUE;
}
/* PROCESS API */
void
SystemExec::make_envp()
{
; /* environemt is copied over with CreateProcess(...,env=0 ,..) */
}
void
SystemExec::make_wargs (char** a)
{
std::string wa = cmd;
if (cmd[0] != '"' && cmd[cmd.size()] != '"' && strchr(cmd.c_str(), ' ')) { wa = "\"" + cmd + "\""; }
std::replace(cmd.begin(), cmd.end(), '/', '\\' );
char **tmp = ++a;
while (tmp && *tmp) {
wa.append(" \"");
wa.append(*tmp);
if (strlen(*tmp) > 0 && (*tmp)[strlen(*tmp) - 1] == '\\') {
wa.append("\\");
}
wa.append("\"");
tmp++;
}
w_args = strdup(wa.c_str());
}
void
SystemExec::make_argp (std::string args)
{
std::string wa = cmd;
if (cmd[0] != '"' && cmd[cmd.size()] != '"' && strchr(cmd.c_str(), ' ')) { wa = "\"" + cmd + "\""; }
std::replace(cmd.begin(), cmd.end(), '/', '\\' );
wa.append(" ");
wa.append(args);
w_args = strdup(wa.c_str());
}
void
SystemExec::terminate ()
{
::pthread_mutex_lock(&write_lock);
close_stdin();
if (pid) {
/* terminate */
EnumWindows(my_terminateApp, (LPARAM)pid->dwProcessId);
PostThreadMessage(pid->dwThreadId, WM_CLOSE, 0, 0);
/* kill ! */
TerminateProcess(pid->hProcess, 0xf291);
CloseHandle(pid->hThread);
CloseHandle(pid->hProcess);
destroy_pipe(stdinP);
destroy_pipe(stdoutP);
destroy_pipe(stderrP);
delete pid;
pid=0;
}
::pthread_mutex_unlock(&write_lock);
}
int
SystemExec::wait (int options)
{
while (is_running()) {
WaitForSingleObject(pid->hProcess, 40);
}
return 0;
}
bool
SystemExec::is_running ()
{
if (!pid) return false;
DWORD exit_code;
if (GetExitCodeProcess(pid->hProcess, &exit_code)) {
if (exit_code == STILL_ACTIVE) return true;
}
return false;
}
int
SystemExec::start (StdErrMode stderr_mode, const char * /*vfork_exec_wrapper*/)
{
char* working_dir = 0;
if (pid) { return 0; }
pid = new PROCESS_INFORMATION;
memset(pid, 0, sizeof(PROCESS_INFORMATION));
create_pipe(stdinP, true);
create_pipe(stdoutP, false);
if (stderr_mode == MergeWithStdin) {
/* merge stout & stderr */
DuplicateHandle(GetCurrentProcess(), stdoutP[1], GetCurrentProcess(), &stderrP[1], 0, TRUE, DUPLICATE_SAME_ACCESS);
} else if (stderr_mode == IgnoreAndClose) {
//TODO read/flush this pipe or close it...
create_pipe(stderrP, false);
} else {
//TODO: keep stderr of this process mode.
}
bool success = false;
STARTUPINFOA startupInfo = { sizeof(STARTUPINFO), 0, 0, 0,
(unsigned long)CW_USEDEFAULT, (unsigned long)CW_USEDEFAULT,
(unsigned long)CW_USEDEFAULT, (unsigned long)CW_USEDEFAULT,
0, 0, 0,
STARTF_USESTDHANDLES,
0, 0, 0,
stdinP[0], stdoutP[1], stderrP[1]
};
success = CreateProcess(0, w_args,
0, 0, /* bInheritHandles = */ TRUE,
(CREATE_NO_WINDOW&0) | CREATE_UNICODE_ENVIRONMENT | (0&CREATE_NEW_CONSOLE),
/*env = */ 0,
working_dir,
&startupInfo, pid);
if (stdinP[0] != INVALID_HANDLE_VALUE) {
CloseHandle(stdinP[0]);
stdinP[0] = INVALID_HANDLE_VALUE;
}
if (stdoutP[1] != INVALID_HANDLE_VALUE) {
CloseHandle(stdoutP[1]);
stdoutP[1] = INVALID_HANDLE_VALUE;
}
if (stderrP[1] != INVALID_HANDLE_VALUE) {
CloseHandle(stderrP[1]);
stderrP[1] = INVALID_HANDLE_VALUE;
}
if (!success) {
CloseHandle(pid->hThread);
CloseHandle(pid->hProcess);
destroy_pipe(stdinP);
destroy_pipe(stdoutP);
destroy_pipe(stderrP);
delete pid;
pid=0;
return -1;
}
int rv = pthread_create (&thread_id_tt, NULL, interposer_thread, this);
thread_active=true;
if (rv) {
thread_active=false;
terminate();
return -2;
}
Sleep(20);
return 0;
}
void
SystemExec::output_interposer()
{
DWORD bytesRead = 0;
char data[BUFSIZ];
#if 0 // untested code to set up nonblocking
unsigned long l = 1;
ioctlsocket(stdoutP[0], FIONBIO, &l);
#endif
while(1) {
#if 0 // for non-blocking pipes..
DWORD bytesAvail = 0;
PeekNamedPipe(stdoutP[0], 0, 0, 0, &bytesAvail, 0);
if (bytesAvail < 1) {Sleep(500); printf("N/A\n"); continue;}
#endif
if (stdoutP[0] == INVALID_HANDLE_VALUE) break;
if (!ReadFile(stdoutP[0], data, BUFSIZ - 1, &bytesRead, 0)) {
DWORD err = GetLastError();
if (err == ERROR_IO_PENDING) continue;
break;
}
if (bytesRead < 1) continue; /* actually not needed; but this is safe. */
data[bytesRead] = 0;
ReadStdout(data, bytesRead); /* EMIT SIGNAL */
}
Terminated(); /* EMIT SIGNAL */
pthread_exit(0);
}
void
SystemExec::close_stdin()
{
if (stdinP[0] != INVALID_HANDLE_VALUE) FlushFileBuffers (stdinP[0]);
if (stdinP[1] != INVALID_HANDLE_VALUE) FlushFileBuffers (stdinP[1]);
Sleep(200);
destroy_pipe (stdinP);
}
size_t
SystemExec::write_to_stdin (const void* data, size_t bytes)
{
DWORD r, c;
::pthread_mutex_lock (&write_lock);
c=0;
while (c < bytes) {
if (!WriteFile (stdinP[1], &((const char*)data)[c], bytes - c, &r, NULL)) {
if (GetLastError() == 0xE8 /*NT_STATUS_INVALID_USER_BUFFER*/) {
Sleep(100);
continue;
} else {
fprintf(stderr, "SYSTEM-EXEC: stdin write error.\n");
break;
}
}
c += r;
}
::pthread_mutex_unlock(&write_lock);
return c;
}
/* end windows process */
#else
/* UNIX/POSIX process */
extern char **environ;
void
SystemExec::make_envp()
{
int i = 0;
envp = (char **) calloc(1, sizeof(char*));
/* copy current environment */
for (i = 0; environ[i]; ++i) {
envp[i] = strdup(environ[i]);
envp = (char **) realloc(envp, (i+2) * sizeof(char*));
}
envp[i] = 0;
}
void
SystemExec::make_argp(std::string args)
{
int argn = 1;
char *cp1;
char *cp2;
char *carg = strdup(args.c_str());
argp = (char **) malloc((argn + 1) * sizeof(char *));
if (argp == (char **) 0) {
free(carg);
return; // FATAL
}
argp[0] = strdup(cmd.c_str());
/* TODO: quotations and escapes
* http://stackoverflow.com/questions/1511797/convert-string-to-argv-in-c
*
* It's actually not needed. All relevant invocations specify 'argp' directly.
* Only 'xjadeo -L -R' uses this function and that uses neither quotations
* nor arguments with white-space.
*/
for (cp1 = cp2 = carg; *cp2 != '\0'; ++cp2) {
if (*cp2 == ' ') {
*cp2 = '\0';
argp[argn++] = strdup(cp1);
cp1 = cp2 + 1;
argp = (char **) realloc(argp, (argn + 1) * sizeof(char *));
}
}
if (cp2 != cp1) {
argp[argn++] = strdup(cp1);
argp = (char **) realloc(argp, (argn + 1) * sizeof(char *));
}
argp[argn] = (char *) 0;
free(carg);
}
void
SystemExec::terminate ()
{
::pthread_mutex_lock(&write_lock);
/* close stdin in an attempt to get the child to exit cleanly.
*/
close_stdin();
if (pid) {
::usleep(200000);
sched_yield();
wait(WNOHANG);
}
/* if pid is non-zero, the child task is still executing (i.e. it did
* not exit in response to stdin being closed). try to kill it.
*/
if (pid) {
::kill(pid, SIGTERM);
::usleep(250000);
sched_yield();
wait(WNOHANG);
}
/* if pid is non-zero, the child task is STILL executing after being
* sent SIGTERM. Act tough ... send SIGKILL
*/
if (pid) {
::fprintf(stderr, "Process is still running! trying SIGKILL\n");
::kill(pid, SIGKILL);
}
wait();
if (thread_active) pthread_join(thread_id_tt, NULL);
thread_active = false;
assert(pid == 0);
::pthread_mutex_unlock(&write_lock);
}
int
SystemExec::wait (int options)
{
int status = 0;
int ret;
if (pid == 0) return -1;
ret = waitpid (pid, &status, options);
if (ret == pid) {
if (WEXITSTATUS(status) || WIFSIGNALED(status)) {
pid=0;
}
} else {
if (ret != 0) {
if (errno == ECHILD) {
/* no currently running children, reset pid */
pid=0;
}
} /* else the process is still running */
}
return status;
}
bool
SystemExec::is_running ()
{
int status = 0;
if (pid == 0) {
return false;
}
if (::waitpid (pid, &status, WNOHANG)==0) {
return true;
}
return false;
}
int
SystemExec::start (StdErrMode stderr_mode, const char *vfork_exec_wrapper)
{
if (is_running ()) {
return 0;
}
int r;
if (::pipe(pin) < 0 || ::pipe(pout) < 0 || ::pipe(pok) < 0) {
/* Something unexpected went wrong creating a pipe. */
return -1;
}
r = ::vfork();
if (r < 0) {
/* failed to fork */
return -2;
}
if (r > 0) {
/* main */
pid = r;
/* check if execve was successful. */
close_fd (pok[1]);
char buf;
for (;;) {
ssize_t n = ::read (pok[0], &buf, 1);
if (n == 1) {
/* child process returned from execve */
pid=0;
close_fd (pok[0]);
close_fd (pok[1]);
close_fd (pin[1]);
close_fd (pin[0]);
close_fd (pout[1]);
close_fd (pout[0]);
return -3;
} else if (n == -1) {
if (errno==EAGAIN || errno==EINTR) {
continue;
}
}
break;
}
close_fd (pok[0]);
/* child started successfully */
close_fd (pout[1]);
close_fd (pin[0]);
int rv = pthread_create (&thread_id_tt, NULL, interposer_thread, this);
thread_active=true;
if (rv) {
thread_active=false;
terminate();
return -2;
}
return 0; /* all systems go - return to main */
}
/* XXX this should be done before vfork()
* calling malloc here only increases the time vfork() blocks
*/
int argn = 0;
for (int i = 0; argp[i]; ++i) { argn++; }
argx = (char **) malloc ((argn + 10) * sizeof(char*));
argx[0] = strdup (vfork_exec_wrapper);
#define FDARG(NUM, FDN) \
argx[NUM] = (char*) calloc(6, sizeof(char)); snprintf(argx[NUM], 6, "%d", FDN);
FDARG (1, pok[0])
FDARG (2, pok[1])
FDARG (3, pin[0])
FDARG (4, pin[1])
FDARG (5, pout[0])
FDARG (6, pout[1])
FDARG (7, stderr_mode)
FDARG (8, nicelevel)
for (int i = 0; argp[i]; ++i) {
argx[9+i] = argp[i];
}
argx[argn+9] = NULL;
::execve (argx[0], argx, envp);
/* if we reach here something went wrong.. */
char buf = 0;
(void) ::write (pok[1], &buf, 1);
close_fd (pok[1]);
_exit (EXIT_FAILURE);
return -1;
}
void
SystemExec::output_interposer ()
{
int rfd = pout[0];
char buf[BUFSIZ];
ssize_t r;
unsigned long l = 1;
ioctl (rfd, FIONBIO, &l); // set non-blocking I/O
for (;fcntl (rfd, F_GETFL) != -1;) {
r = read (rfd, buf, BUFSIZ - 1);
if (r < 0 && (errno == EINTR || errno == EAGAIN)) {
/* wait till ready to read */
struct pollfd pfd;
pfd.fd = rfd;
pfd.events = POLLIN|POLLERR|POLLHUP;
int rv = poll (&pfd, 1, -1);
if (rv == -1) {
break;
}
if (pfd.revents & (POLLERR|POLLHUP)) {
break;
}
if (rv == 1 && pfd.revents & POLLIN) {
/* back to read(2) call */
continue;
}
}
if (r <= 0) {
break;
}
buf[r]=0;
std::string rv = std::string (buf, r);
ReadStdout (rv, r); /* EMIT SIGNAL */
}
Terminated (); /* EMIT SIGNAL */
pthread_exit (0);
}
void
SystemExec::close_stdin()
{
if (pin[1] < 0) {
return;
}
close_fd (pin[0]);
close_fd (pin[1]);
close_fd (pout[0]);
close_fd (pout[1]);
}
size_t
SystemExec::write_to_stdin (const void* data, size_t bytes)
{
ssize_t r;
size_t c;
::pthread_mutex_lock (&write_lock);
c = 0;
while (c < bytes) {
for (;;) {
r = ::write (pin[1], &((const char*)data)[c], bytes - c);
if (r < 0 && (errno == EINTR || errno == EAGAIN)) {
sleep(1);
continue;
}
if ((size_t) r != (bytes-c)) {
::pthread_mutex_unlock(&write_lock);
return c;
}
break;
}
c += r;
}
fsync (pin[1]);
::pthread_mutex_unlock(&write_lock);
return c;
}
#endif // end UNIX process