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/**
* ======================== legal notice ======================
*
* File: CommandReader.cc
* Created: 30. Juli 2012, 06:42
* Author: <a href="mailto:geronimo013@gmx.de">Geronimo</a>
* Project: libIO: classes for files, filesystem and input/output
*
* CMP - compound media player
*
* is a client/server mediaplayer intended to play any media from any workstation
* without the need to export or mount shares. cmps is an easy to use backend
* with a (ready to use) HTML-interface. Additionally the backend supports
* authentication via HTTP-digest authorization.
* cmpc is a client with vdr-like osd-menues.
*
* Copyright (c) 2012 Reinhard Mantey, some rights reserved!
* published under Creative Commons by-sa
* For details see http://creativecommons.org/licenses/by-sa/3.0/
*
* The cmp project's homepage is at http://projects.vdr-developer.org/projects/cmp
*
* --------------------------------------------------------------
*/
#include <CommandReader.h>
#include <Logging.h>
#include <stdarg.h>
#include <errno.h>
#include <wait.h>
int cCommandReader::fdMax = 0;
cCommandReader::cCommandReader(const char *cmd)
: pid(-1)
{
args.push_back(cmd);
}
cCommandReader::~cCommandReader()
{
Close();
}
void cCommandReader::AddCommandParameter(const char* Param)
{
args.push_back(Param);
}
void cCommandReader::Close(void)
{
int status = 0;
if (!fdMax) fdMax = getdtablesize();
if (fd > 0 && fd < fdMax) {
close(fd);
isyslog("closed fd #%d", fd);
}
fd = -1;
if (pid != waitpid(pid, &status, 0)) {
esyslog("ERROR: failed to wait for child #%d - error #%d", pid, errno);
}
else {
isyslog("child exit status: %d", WEXITSTATUS(status));
}
pid = -1;
}
bool cCommandReader::Open(void)
{
enum { FDRead, FDWrite };
int child2Parent[2] = {0};
if (pipe(child2Parent)) {
esyslog("ERROR: failed to create child2Parent-pipe #%d", errno);
return false;
}
switch ((pid = fork())) {
case -1:
esyslog("fork failed");
close(child2Parent[0]);
close(child2Parent[1]);
return false;
case 0: { /* child */
const char *cmdArgs[args.size() + 1];
for (size_t i=0; i < args.size(); ++i) {
cmdArgs[i] = args[i].c_str();
}
cmdArgs[args.size()] = 0;
if (dup2(child2Parent[FDWrite], STDOUT_FILENO) < 0) {
esyslog("ERROR: failed to create childs stdout #%d", errno);
exit(-1);
}
if (dup2(child2Parent[FDWrite], STDERR_FILENO) < 0) {
esyslog("ERROR: failed to create childs stderr #%d", errno);
exit(-1);
}
if (close(child2Parent[FDRead])) {
esyslog("ERROR: failed to close childs read-end of the pipe #%d", errno);
exit(-1);
}
execv(args[0].c_str(), (char *const*) cmdArgs);
esyslog("should never be reached! #1");
exit(-1);
} break;
default: { /* parent */
if (close(child2Parent[FDWrite])) {
esyslog("ERROR: failed to close write end from parent side!");
exit(-1);
}
isyslog("child process #%d started ... fd %d", pid, child2Parent[FDRead]);
fd = child2Parent[FDRead];
return true;
}
}
esyslog("should never be reached! #2");
close(child2Parent[0]);
close(child2Parent[1]);
return false;
}
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