//examine /proc/self/fd for unknown connections
void dmtcp::FileConnList::scanForPreExisting()
{
// FIXME: Detect stdin/out/err fds to detect duplicates.
dmtcp::vector<int> fds = jalib::Filesystem::ListOpenFds();
dmtcp::string ctty = jalib::Filesystem::GetControllingTerm();
dmtcp::string parentCtty = jalib::Filesystem::GetControllingTerm(getppid());
for (size_t i = 0; i < fds.size(); ++i) {
int fd = fds[i];
if (!Util::isValidFd(fd)) continue;
if (dmtcp_is_protected_fd(fd)) continue;
struct stat statbuf;
JASSERT(fstat(fd, &statbuf) == 0);
bool isRegularFile = (S_ISREG(statbuf.st_mode) || S_ISCHR(statbuf.st_mode) ||
S_ISDIR(statbuf.st_mode) || S_ISBLK(statbuf.st_mode));
dmtcp::string device = _resolveSymlink(_procFDPath(fd));
JTRACE("scanning pre-existing device") (fd) (device);
if (device == ctty || device == parentCtty) {
// Search if this is duplicate connection
iterator conit;
int cttyType = (device == ctty) ? PtyConnection::PTY_CTTY
: PtyConnection::PTY_PARENT_CTTY;
for (conit = begin(); conit != end(); conit++) {
Connection *c = conit->second;
if (c->subType() == cttyType &&
((PtyConnection*)c)->ptsName() == device) {
processDup(c->getFds()[0], fd);
break;
}
}
if (conit == end()) {
// FIXME: Merge this code with the code in processFileConnection
PtyConnection *con = new PtyConnection(fd, (const char*) device.c_str(),
-1, -1, cttyType);
// Check comments in FileConnList::postRestart() for the explanation
// about isPreExistingCTTY.
con->markPreExistingCTTY();
add(fd, (Connection*)con);
}
} else if(dmtcp_is_bq_file && dmtcp_is_bq_file(device.c_str())) {
if (isRegularFile) {
Connection *c = findDuplication(fd, device.c_str());
if (c != NULL) {
c->addFd(fd);
continue;
}
}
processFileConnection(fd, device.c_str(), -1, -1);
} else if( fd <= 2 ){
add(fd, new StdioConnection(fd));
} else if (Util::strStartsWith(device, "/")) {
if (isRegularFile) {
Connection *c = findDuplication(fd, device.c_str());
if (c != NULL) {
c->addFd(fd);
continue;
}
}
processFileConnection(fd, device.c_str(), -1, -1);
}
}
}
