extern "C" int ttyname_r(int fd, char *buf, size_t buflen)
{
char tmpbuf[64];
DMTCP_PLUGIN_DISABLE_CKPT();
int ret = _real_ttyname_r(fd, tmpbuf, sizeof(tmpbuf));
if (ret == 0 && strcmp(tmpbuf, "/dev/tty") != 0) {
Connection* c = FileConnList::instance().getConnection(fd);
JASSERT(c != NULL) (fd) (tmpbuf);
PtyConnection* ptyCon =(PtyConnection*) c;
string virtPtsName = ptyCon->virtPtsName();
if (virtPtsName.length() >= buflen) {
JWARNING(false) (virtPtsName) (virtPtsName.length()) (buflen)
.Text("fake ptsname() too long for user buffer");
errno = ERANGE;
ret = -1;
} else {
strncpy(buf, virtPtsName.c_str(), buflen);
}
}
DMTCP_PLUGIN_ENABLE_CKPT();
return ret;
}
void dmtcp::FileConnList::refill(bool isRestart)
{
// Check comments in PtyConnection::preRefill()/refill()
for (iterator i = begin(); i != end(); ++i) {
Connection* con = i->second;
if (con->hasLock() && con->conType() == Connection::PTY) {
PtyConnection *pcon = (PtyConnection*) con;
pcon->preRefill(isRestart);
}
}
ConnectionList::refill(isRestart);
}
void FileConnList::refill(bool isRestart)
{
// Check comments in PtyConnection::preRefill()/refill()
for (iterator i = begin(); i != end(); ++i) {
Connection* con = i->second;
if (con->hasLock() && con->conType() == Connection::PTY) {
PtyConnection *pcon = (PtyConnection*) con;
pcon->preRefill(isRestart);
}
}
if (isRestart) {
// The backing file will be created as a result of restoreShmArea. We need
// to unlink all such files in the resume() call below.
for (size_t i = 0; i < missingUnlinkedShmFiles.size(); i++) {
recreateShmFileAndMap(missingUnlinkedShmFiles[i]);
}
}
ConnectionList::refill(isRestart);
}
void FileConnList::postRestart()
{
/* It is possible to have two different connection-ids for a pre-existing
* CTTY in two or more different process trees. In this case, only one of the
* several process trees would be able to acquire a lock on the underlying
* fd. The send-receive fd logic fails in this case due to different
* connection-ids. Therefore, we let every process do a postRestart to
* reopen the CTTY.
*
* TODO: A better fix would be to have a unique connection-id for each
* pre-existing CTTY that is then used by all process trees. It can be
* implemented by using the SharedData area.
*/
for (iterator i = begin(); i != end(); ++i) {
Connection* con = i->second;
if (!con->hasLock() && con->conType() == Connection::PTY &&
con->isPreExistingCTTY()) {
PtyConnection *pcon = (PtyConnection*) con;
pcon->postRestart();
}
}
/* Try to map the file as is, if it already exists on the disk.
*/
for (size_t i = 0; i < unlinkedShmAreas.size(); i++) {
if (jalib::Filesystem::FileExists(unlinkedShmAreas[i].name)) {
// TODO(kapil): Verify the file contents.
JWARNING(false) (unlinkedShmAreas[i].name)
.Text("File was unlinked at ckpt but is currently present on disk; "
"remove it and try again.");
restoreShmArea(unlinkedShmAreas[i]);
} else {
missingUnlinkedShmFiles.push_back(unlinkedShmAreas[i]);
}
}
ConnectionList::postRestart();
}
static int ptsname_r_work(int fd, char * buf, size_t buflen)
{
JTRACE("Calling ptsname_r");
Connection* c = FileConnList::instance().getConnection(fd);
PtyConnection* ptyCon =(PtyConnection*) c;
string virtPtsName = ptyCon->virtPtsName();
JTRACE("ptsname_r") (virtPtsName);
if (virtPtsName.length() >= buflen)
{
JWARNING(false) (virtPtsName) (virtPtsName.length()) (buflen)
.Text("fake ptsname() too long for user buffer");
errno = ERANGE;
return -1;
}
strcpy(buf, virtPtsName.c_str());
return 0;
}
void dmtcp::FileConnList::postRestart()
{
/* It is possible to have two different connection-ids for a pre-existing
* CTTY in two or more different process trees. In this case, only one of the
* several process trees would be able to acquire a lock on the underlying
* fd. The send-receive fd logic fails in this case due to different
* connection-ids. Therefore, we let every process do a postRestart to
* reopen the CTTY.
*
* TODO: A better fix would be to have a unique connection-id for each
* pre-existing CTTY that is then used by all process trees. It can be
* implemented by using the SharedData area.
*/
for (iterator i = begin(); i != end(); ++i) {
Connection* con = i->second;
if (!con->hasLock() && con->conType() == Connection::PTY &&
con->isPreExistingCTTY()) {
PtyConnection *pcon = (PtyConnection*) con;
pcon->postRestart();
}
}
ConnectionList::postRestart();
}
//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);
}
}
}
