// See comments above for open_ckpt_to_read()
int dmtcp::CkptSerializer::openDmtcpCheckpointFile(const dmtcp::string& path,
int *offset,
int skipBytes)
{
char buf[1024];
// Function also sets dmtcp::ext_decomp_pid::ConnectionToFds
int fd = open_ckpt_to_read(path.c_str());
// The rest of this function is for compatibility with original definition.
JASSERT(fd >= 0) (path) .Text("Failed to open file.");
const int len = strlen(DMTCP_FILE_HEADER);
JASSERT(_real_read(fd, buf, len) == len)(path) .Text("_real_read() failed");
if (strncmp(buf, DMTCP_FILE_HEADER, len) == 0) {
JTRACE("opened checkpoint file [uncompressed]")(path);
} else {
close_ckpt_to_read(fd);
fd = open_ckpt_to_read(path.c_str()); /* Re-open from beginning */
JASSERT(fd >= 0) (path) .Text("Failed to open file.");
}
if (offset != NULL) {
*offset = strlen(DMTCP_FILE_HEADER);
}
skipBytes -= strlen(DMTCP_FILE_HEADER);
if (skipBytes > 0) {
JASSERT(dmtcp::Util::skipBytes(fd, skipBytes) == skipBytes) (skipBytes);
}
return fd;
}
int openSharedFile(dmtcp::string name, int flags)
{
int fd;
// try to create, truncate & open file
if ((fd = open(name.c_str(), O_EXCL|O_CREAT|O_TRUNC | flags, 0600)) >= 0) {
return fd;
}
if (fd < 0 && errno == EEXIST) {
if ((fd = open(name.c_str(), flags, 0600)) > 0) {
return fd;
}
}
// unable to create & open OR open
JASSERT(false)(name)(strerror(errno)).Text("Cannot open file");
return -1;
}
const DmtcpLocalStatus* __real_dmtcpGetLocalStatus(){
//these must be static so their memory is not deleted.
static dmtcp::string ckpt;
static dmtcp::string pid;
static DmtcpLocalStatus status;
ckpt.reserve(1024);
//get filenames
pid=dmtcp::UniquePid::ThisProcess().toString();
ckpt=dmtcp::UniquePid::getCkptFilename();
status.numCheckpoints = numCheckpoints;
status.numRestarts = numRestarts;
status.checkpointFilename = ckpt.c_str();
status.uniquePidStr = pid.c_str();
return &status;
}
static int queryPbsConfig(dmtcp::string option, dmtcp::string &pbs_config)
{
int fds[2];
const char *pbs_config_path = "pbs-config";
static const char *pbs_config_args[] = { "pbs-config", option.c_str(), NULL };
int cpid;
if( pipe(fds) == -1){
// just go away - we cannot serve this request
JTRACE("Cannot create pipe to execute pbs-config to find Torque/PBS library!");
return -1;
}
cpid = _real_fork();
if( cpid < 0 ){
JTRACE( "ERROR: cannot execute pbs-config. Will not run tm_spawn!");
return -1;
}
if( cpid == 0 ){
JTRACE ( "child process, will exec into external de-compressor");
fds[1] = dup(dup(dup(fds[1])));
close(fds[0]);
JASSERT(dup2(fds[1], STDOUT_FILENO) == STDOUT_FILENO);
close(fds[1]);
_real_execvp(pbs_config_path, (char **)pbs_config_args);
/* should not get here */
JASSERT(false)("ERROR: Failed to exec pbs-config. tm_spawn will fail with TM_BADINIT")(strerror(errno));
exit(0);
}
/* parent process */
JTRACE ( "created child process for pbs-config")(cpid);
int status;
if( waitpid(cpid,&status,0) < 0 ){
return -1;
}
if( !( WIFEXITED(status) && WEXITSTATUS(status) == 0 ) ){
return -1;
}
// set descriptor as non-blocking
// JTRACE ( "Set pipe fds[0] as non-blocking");
int flags = fcntl(fds[0], F_GETFL);
fcntl(fds[0], F_SETFL, flags | O_NONBLOCK);
//JTRACE ( "Read pbs-config output from pipe");
pbs_config = "";
char buf[256];
int count = 0;
while( (count = read(fds[0], buf, 255)) > 0 ){
buf[count] = '\0';
pbs_config += dmtcp::string() + buf;
}
JTRACE ( "pbs-config output:")(pbs_config);
return 0;
}
static void writeCurrentLogFileNameToPrevLogFile(dmtcp::string& path)
{
#ifdef DEBUG
dmtcp::ostringstream o;
o << "========================================\n"
<< "This process exec()'d into a new program\n"
<< "Program Name: " << jalib::Filesystem::GetProgramName() << "\n"
<< "New JAssertLog Path: " << getLogFilePath() << "\n"
<< "========================================\n";
int fd = open(path.c_str(), O_WRONLY | O_APPEND, 0);
if (fd != -1) {
Util::writeAll(fd, o.str().c_str(), o.str().length());
}
_real_close(fd);
#endif
}
int dmtcp::CkptSerializer::openDmtcpCheckpointFile(const dmtcp::string& path){
int fd = open( path.c_str(), O_RDONLY);
JASSERT(fd>=0)(path).Text("Failed to open file.");
char buf[512];
const int len = strlen(DMTCP_FILE_HEADER);
JASSERT(_real_read(fd, buf, len)==len)(path).Text("_real_read() failed");
if(strncmp(buf, DMTCP_FILE_HEADER, len)==0){
JTRACE("opened checkpoint file [uncompressed]")(path);
return fd;
}else{
close(fd);
dmtcp::string cmd = dmtcp::string()+"exec gzip -d - < '"+path+"'";
FILE* t = _real_popen(cmd.c_str(),"r");
JASSERT(t!=NULL)(path)(cmd).Text("Failed to launch gzip.");
JTRACE ( "created gzip child process to uncompress checkpoint file");
fd = fileno(t);
JASSERT(_real_read(fd, buf, len)==len)(cmd)(path).Text("Invalid checkpoint file");
JASSERT(strncmp(buf, DMTCP_FILE_HEADER, len)==0)(path).Text("Invalid checkpoint file");
JTRACE("opened checkpoint file [compressed]")(path);
return fd;
}
}
const char* dmtcp_get_uniquepid_str()
{
static dmtcp::string uniquepid_str;
uniquepid_str = dmtcp::UniquePid::ThisProcess(true).toString();
return uniquepid_str.c_str();
}
const char* dmtcp_get_tmpdir()
{
static dmtcp::string tmpdir;
tmpdir = dmtcp::UniquePid::getTmpDir();
return tmpdir.c_str();
}
bool dmtcp::Util::strEndsWith(const dmtcp::string& str, const char *pattern)
{
return strEndsWith(str.c_str(), pattern);
}
void dmtcp::DmtcpCoordinatorAPI::sendCoordinatorHandshake (
const dmtcp::string& progname,
UniquePid compGroup /*= UniquePid()*/,
int np /*= -1*/,
DmtcpMessageType msgType /*= DMT_HELLO_COORDINATOR*/)
{
JTRACE("sending coordinator handshake")(UniquePid::ThisProcess());
dmtcp::string hostname = jalib::Filesystem::GetCurrentHostname();
const char *prefixPathEnv = getenv(ENV_VAR_PREFIX_PATH);
dmtcp::string prefixDir;
DmtcpMessage hello_local;
hello_local.type = msgType;
hello_local.params[0] = np;
hello_local.compGroup = compGroup;
hello_local.restorePort = theRestorePort;
if (getenv(ENV_VAR_VIRTUAL_PID) == NULL) {
hello_local.virtualPid = -1;
} else {
hello_local.virtualPid = (pid_t) atoi(getenv(ENV_VAR_VIRTUAL_PID));
}
const char* interval = getenv ( ENV_VAR_CKPT_INTR );
/* DmtcpMessage constructor default:
* hello_local.theCheckpointInterval: DMTCPMESSAGE_SAME_CKPT_INTERVAL
*/
if ( interval != NULL )
hello_local.theCheckpointInterval = jalib::StringToInt ( interval );
// Tell the coordinator the ckpt interval only once. It can change later.
_dmtcp_unsetenv ( ENV_VAR_CKPT_INTR );
hello_local.extraBytes = hostname.length() + 1 + progname.length() + 1;
if (prefixPathEnv != NULL) {
/* If --prefix was defined then this process is either running on the local
* node (the home of first process in the comptation) or a remote node.
*
* If the process is running on the local node, the prefix-path-env may be
* different from the prefix-dir of this binary, in which case, we want to
* send the prefix-path of this binary to the coordinator and the
* coordinator will save it as the local-prefix.
*
* However, if this is running on a remote node, the prefix-path-env would
* be the same as the prefix-path of this binary and we should send the
* prefix-path-env to the coordinator and the coordinator will note this as
* the remote-prefix.
*/
dmtcp::string utilDirPrefix =
jalib::Filesystem::DirName(getenv(ENV_VAR_UTILITY_DIR));
if (utilDirPrefix == jalib::Filesystem::ResolveSymlink(prefixPathEnv)) {
prefixDir = prefixPathEnv;
} else {
prefixDir = utilDirPrefix;
}
hello_local.extraBytes += prefixDir.length() + 1;
}
_coordinatorSocket << hello_local;
_coordinatorSocket.writeAll( hostname.c_str(),hostname.length()+1);
_coordinatorSocket.writeAll( progname.c_str(),progname.length()+1);
if (!prefixDir.empty()) {
_coordinatorSocket.writeAll(prefixDir.c_str(), prefixDir.length()+1);
}
}
EXTERNC const char* dmtcp_get_ckpt_files_subdir(void)
{
static dmtcp::string tmpdir;
tmpdir = dmtcp::ProcessInfo::instance().getCkptFilesSubDir();
return tmpdir.c_str();
}
EXTERNC const char* dmtcp_get_ckpt_filename(void)
{
static dmtcp::string filename;
filename = dmtcp::ProcessInfo::instance().getCkptFilename();
return filename.c_str();
}
EXTERNC const char* dmtcp_get_coord_ckpt_dir(void)
{
static dmtcp::string dir;
dir = CoordinatorAPI::instance().getCoordCkptDir();
return dir.c_str();
}
EXTERNC const char* dmtcp_get_ckpt_dir()
{
static dmtcp::string tmpdir;
tmpdir = dmtcp::ProcessInfo::instance().getCkptDir();
return tmpdir.c_str();
}
void runMtcpRestore(const char* path, int offset, size_t argvSize,
size_t envSize)
{
static dmtcp::string mtcprestart =
jalib::Filesystem::FindHelperUtility ("mtcp_restart");
// Tell mtcp_restart process to write its debugging information to
// PROTECTED_STDERR_FD. This way we prevent it from spitting out garbage onto
// FD_STDERR if it is being used by the user process in a special way.
char protected_stderr_fd_str[16];
sprintf(protected_stderr_fd_str, "%d", PROTECTED_STDERR_FD);
#ifdef USE_MTCP_FD_CALLING
int fd = ConnectionToFds::openMtcpCheckpointFile(path);
char buf[64];
char buf2[64];
sprintf(buf, "%d", fd);
// gzip_child_pid set by openMtcpCheckpointFile() above.
sprintf(buf2, "%d", dmtcp::ConnectionToFds::gzip_child_pid);
char* newArgs[] = {
(char*) mtcprestart.c_str(),
(char*) "--stderr-fd",
protected_stderr_fd_str,
(char*) "--fd",
buf,
(char*) "--gzip-child-pid",
buf2,
NULL
};
if (dmtcp::ConnectionToFds::gzip_child_pid == -1) { // If no gzip compression
newArgs[3] = NULL;
}
JTRACE ("launching mtcp_restart --fd")(fd)(path);
#else
char buf[64];
sprintf(buf, "%d", offset);
char* newArgs[] = {
(char*) mtcprestart.c_str(),
(char*) "--stderr-fd",
protected_stderr_fd_str,
(char*) "--offset",
buf,
(char*) path,
NULL
};
JTRACE ("launching mtcp_restart --offset")(path)(offset);
#endif
// Create the placeholder for "MTCP_OLDPERS" environment.
// setenv("MTCP_OLDPERS_DUMMY", "XXXXXXXXXXXXXXXX", 1);
// FIXME: Put an explanation of the logic below. -- Kapil
#define ENV_PTR(x) ((char*) (getenv(x) - strlen(x) - 1))
char* dummyEnviron = NULL;
const int dummyEnvironIndex = 0; // index in newEnv[]
const int pathIndex = 1; // index in newEnv[]
// Eventually, newEnv = {ENV_PTR("MTCP_OLDPERS"), ENV_PTR("PATH"), NULL}
char* newEnv[3] = {NULL, NULL, NULL};
// Will put ENV_PTR("MTCP_OLDPERS") here.
newEnv[dummyEnvironIndex] = (char*) dummyEnviron;
newEnv[pathIndex] = (getenv("PATH") ? ENV_PTR("PATH") : NULL);
size_t newArgsSize = 0;
for (int i = 0; newArgs[i] != 0; i++) {
newArgsSize += strlen(newArgs[i]) + 1;
}
size_t newEnvSize = 0;
for (int i = 0; newEnv[i] != 0; i++) {
newEnvSize += strlen(newEnv[i]) + 1;
}
size_t originalArgvEnvSize = argvSize + envSize;
size_t newArgvEnvSize = newArgsSize + newEnvSize + strlen(newArgs[0]);
size_t argvSizeDiff = originalArgvEnvSize - newArgvEnvSize;
dummyEnviron = (char*) malloc(argvSizeDiff);
memset(dummyEnviron, '0', (argvSizeDiff >= 1 ? argvSizeDiff - 1 : 0));
strncpy(dummyEnviron,
ENV_VAR_DMTCP_DUMMY "=0",
strlen(ENV_VAR_DMTCP_DUMMY "="));
dummyEnviron[argvSizeDiff - 1] = '\0';
newEnv[dummyEnvironIndex] = dummyEnviron;
JTRACE("Args/Env Sizes")
(newArgsSize) (newEnvSize) (argvSize) (envSize) (argvSizeDiff);
execve (newArgs[0], newArgs, newEnv);
JASSERT (false) (newArgs[0]) (newArgs[1]) (JASSERT_ERRNO)
.Text ("exec() failed");
}
int main ( int argc, char** argv )
{
initializeJalib();
if (! getenv(ENV_VAR_QUIET))
setenv(ENV_VAR_QUIET, "0", 0);
processArgs(&argc, &argv);
// If --ssh-slave and --prefix both are present, verify that the prefix-dir
// of this binary (dmtcp_checkpoint) is same as the one provided with
// --prefix
if (isSSHSlave && getenv(ENV_VAR_PREFIX_PATH) != NULL) {
const char *str = getenv(ENV_VAR_PREFIX_PATH);
dmtcp::string prefixDir = jalib::Filesystem::ResolveSymlink(str);
dmtcp::string programPrefixDir =
jalib::Filesystem::DirName(jalib::Filesystem::GetProgramDir());
JASSERT(prefixDir == programPrefixDir)
(prefixDir) (programPrefixDir);
}
dmtcp::UniquePid::setTmpDir(getenv(ENV_VAR_TMPDIR));
dmtcp::UniquePid::ThisProcess(true);
dmtcp::Util::initializeLogFile();
#ifdef FORKED_CHECKPOINTING
/* When this is robust, add --forked-checkpointing option on command-line,
* with #ifdef FORKED_CHECKPOINTING around the option, change default of
* configure.ac, dmtcp/configure.ac, to enable, and change them
* from enable-forked... to disable-...
*/
setenv(ENV_VAR_FORKED_CKPT, "1", 1);
#endif
if (jassert_quiet == 0)
JASSERT_STDERR << DMTCP_BANNER;
// This code will go away when zero-mapped pages are implemented in MTCP.
struct rlimit rlim;
getrlimit(RLIMIT_STACK, &rlim);
if (rlim.rlim_cur > 256*1024*1024 && rlim.rlim_cur != RLIM_INFINITY)
JASSERT_STDERR <<
"*** WARNING: RLIMIT_STACK > 1/4 GB. This causes each thread to"
"\n*** receive a 1/4 GB stack segment. Checkpoint/restart will be slow,"
"\n*** and will potentially break if many threads are created."
"\n*** Suggest setting (sh/bash): ulimit -s 10000"
"\n*** (csh/tcsh): limit stacksize 10000"
"\n*** prior to using DMTCP. (This will be fixed in the future, when"
"\n*** DMTCP supports restoring zero-mapped pages.)\n\n\n" ;
// Remove this when zero-mapped pages are supported. For segments with
// no file backing: Start with 4096 (page) offset and keep doubling offset
// until finding region of memory segment with many zeroes.
// Then mark as CS_ZERO_PAGES in MTCP instead of CS_RESTORE (or mark
// entire segment as CS_ZERO_PAGES and then overwrite with CS_RESTORE
// region for portion to be read back from checkpoint image.
// For CS_ZERO_PAGES region, mmap // on restart, but don't write in zeroes.
// Also, after checkpointing segment, munmap zero pages, and mmap them again.
// Don't try to find all pages. The above strategy may increase
// the non-zero-mapped mapped pages to no more than double the actual
// non-zero region (assuming that the zero-mapped pages are contiguous).
// - Gene
testMatlab(argv[0]);
testJava(argv); // Warn that -Xmx flag needed to limit virtual memory size
// If dmtcphijack.so is in standard search path and _also_ has setgid access,
// then LD_PRELOAD will work.
// Otherwise, it will only work if the application does not use setuid and
// setgid access. So, we test // if the application does not use
// setuid/setgid. (See 'man ld.so')
// FIXME: ALSO DO THIS FOR execwrappers.cpp:dmtcpPrepareForExec()
// Should pass dmtcphijack.so path, and let testSetuid determine
// if setgid is set for it. If so, no problem: continue.
// If not, call testScreen() and adapt 'screen' to run using
// Util::patchArgvIfSetuid(argv[0], argv, &newArgv) (which shouldn't
// will just modify argv[0] to point to /tmp/dmtcp-USER@HOST/screen
// and other modifications: doesn't need newArgv).
// If it's not 'screen' and if no setgid for dmtcphijack.so, then testSetuid
// should issue the warning, unset our LD_PRELOAD, and hope for the best.
// A program like /usr/libexec/utempter/utempter (Fedora path)
// is short-lived and can be safely run. Ideally, we should
// disable checkpoints while utempter is running, and enable checkpoints
// when utempter finishes. See possible model at
// execwrappers.cpp:execLibProcessAndExit(), since the same applies
// to running /lib/libXXX.so for running libraries as executables.
if (testSetuid(argv[0])) {
char **newArgv;
// THIS NEXT LINE IS DANGEROUS. MOST setuid PROGRAMS CAN'T RUN UNPRIVILEGED
dmtcp::Util::patchArgvIfSetuid(argv[0], argv, &newArgv);
argv = newArgv;
};
if (argc > 0) {
JTRACE("dmtcp_checkpoint starting new program:")(argv[0]);
}
//set up CHECKPOINT_DIR
if(getenv(ENV_VAR_CHECKPOINT_DIR) == NULL){
const char* ckptDir = get_current_dir_name();
if(ckptDir != NULL ){
//copy to private buffer
static dmtcp::string _buf = ckptDir;
ckptDir = _buf.c_str();
}else{
ckptDir=".";
}
setenv ( ENV_VAR_CHECKPOINT_DIR, ckptDir, 0 );
JTRACE("setting " ENV_VAR_CHECKPOINT_DIR)(ckptDir);
}
dmtcp::string stderrDevice = jalib::Filesystem::ResolveSymlink ( _stderrProcPath() );
//TODO:
// When stderr is a pseudo terminal for IPC between parent/child processes,
// this logic fails and JASSERT may write data to FD 2 (stderr).
// This will cause problems in programs that use FD 2 (stderr) for
// algorithmic things ...
if ( stderrDevice.length() > 0
&& jalib::Filesystem::FileExists ( stderrDevice ) )
setenv ( ENV_VAR_STDERR_PATH,stderrDevice.c_str(), 0 );
else// if( isSSHSlave )
setenv ( ENV_VAR_STDERR_PATH, "/dev/null", 0 );
if ( getenv(ENV_VAR_SIGCKPT) != NULL )
setenv ( "MTCP_SIGCKPT", getenv(ENV_VAR_SIGCKPT), 1);
else
unsetenv("MTCP_SIGCKPT");
if ( checkpointOpenFiles )
setenv( ENV_VAR_CKPT_OPEN_FILES, "1", 0 );
else
unsetenv( ENV_VAR_CKPT_OPEN_FILES);
#ifdef PID_VIRTUALIZATION
setenv( ENV_VAR_ROOT_PROCESS, "1", 1 );
#endif
bool isElf, is32bitElf;
if (dmtcp::Util::elfType(argv[0], &isElf, &is32bitElf) == -1) {
// Couldn't read argv_buf
// FIXME: This could have been a symbolic link. Don't issue an error,
// unless we're sure that the executable is not readable.
JASSERT_STDERR <<
"*** ERROR: Executable to run w/ DMTCP appears not to be readable,\n"
"*** or no such executable in path.\n\n"
<< argv[0] << "\n";
exit(DMTCP_FAIL_RC);
} else {
#if defined(__x86_64__) && !defined(CONFIG_M32)
if (is32bitElf)
JASSERT_STDERR << "*** ERROR: You appear to be checkpointing "
<< "a 32-bit target under 64-bit Linux.\n"
<< "*** If this fails, then please try re-configuring DMTCP:\n"
<< "*** configure --enable-m32 ; make clean ; make\n\n";
#endif
testStaticallyLinked(argv[0]);
}
// UNSET DISPLAY environment variable.
unsetenv("DISPLAY");
// FIXME: Unify this code with code prior to execvp in execwrappers.cpp
// Can use argument to dmtcpPrepareForExec() or getenv("DMTCP_...")
// from DmtcpWorker constructor, to distinguish the two cases.
dmtcp::Util::adjustRlimitStack();
// FIXME: This call should be moved closer to call to execvp().
dmtcp::Util::prepareDlsymWrapper();
if (autoStartCoordinator)
dmtcp::DmtcpCoordinatorAPI::startCoordinatorIfNeeded(allowedModes);
dmtcp::DmtcpCoordinatorAPI coordinatorAPI;
pid_t virtualPid = coordinatorAPI.getVirtualPidFromCoordinator();
if (virtualPid != -1) {
JTRACE("Got virtual pid from coordinator") (virtualPid);
dmtcp::Util::setVirtualPidEnvVar(virtualPid, getppid());
}
// preloadLibs are to set LD_PRELOAD:
// LD_PRELOAD=PLUGIN_LIBS:UTILITY_DIR/dmtcphijack.so:R_LIBSR_UTILITY_DIR/
dmtcp::string preloadLibs = "";
// FIXME: If the colon-separated elements of ENV_VAR_PLUGIN are not
// absolute pathnames, then they must be expanded to absolute pathnames.
// Warn user if an absolute pathname is not valid.
if ( getenv(ENV_VAR_PLUGIN) != NULL ) {
preloadLibs += getenv(ENV_VAR_PLUGIN);
preloadLibs += ":";
}
// FindHelperUtiltiy requires ENV_VAR_UTILITY_DIR to be set
dmtcp::string searchDir = jalib::Filesystem::GetProgramDir();
setenv ( ENV_VAR_UTILITY_DIR, searchDir.c_str(), 0 );
#ifdef PTRACE
preloadLibs += jalib::Filesystem::FindHelperUtility ( "ptracehijack.so" );
preloadLibs += ":";
#endif
preloadLibs += jalib::Filesystem::FindHelperUtility ( "dmtcphijack.so" );
#ifdef PID_VIRTUALIZATION
preloadLibs += ":";
preloadLibs += jalib::Filesystem::FindHelperUtility ( "pidvirt.so" );
#endif
setenv(ENV_VAR_HIJACK_LIBS, preloadLibs.c_str(), 1);
// If dmtcp_checkpoint was called with user LD_PRELOAD, and if
// if dmtcp_checkpoint survived the experience, then pass it back to user.
if (getenv("LD_PRELOAD"))
preloadLibs = preloadLibs + ":" + getenv("LD_PRELOAD");
setenv ( "LD_PRELOAD", preloadLibs.c_str(), 1 );
JTRACE("getting value of LD_PRELOAD")(getenv("LD_PRELOAD"));
//run the user program
char **newArgv = NULL;
if (testScreen(argv, &newArgv))
execvp ( newArgv[0], newArgv );
else
execvp ( argv[0], argv );
//should be unreachable
JASSERT_STDERR <<
"ERROR: Failed to exec(\"" << argv[0] << "\"): " << JASSERT_ERRNO << "\n"
<< "Perhaps it is not in your $PATH?\n"
<< "See `dmtcp_checkpoint --help` for usage.\n";
//fprintf(stderr, theExecFailedMsg, argv[0], JASSERT_ERRNO);
return -1;
}
int main ( int argc, char** argv )
{
for (size_t fd = PROTECTED_FD_START; fd < PROTECTED_FD_END; fd++) {
close(fd);
}
if (! getenv(ENV_VAR_QUIET))
setenv(ENV_VAR_QUIET, "0", 0);
processArgs(&argc, &argv);
initializeJalib();
// If --ssh-slave and --prefix both are present, verify that the prefix-dir
// of this binary (dmtcp_launch) is same as the one provided with
// --prefix
if (isSSHSlave && getenv(ENV_VAR_PREFIX_PATH) != NULL) {
char buf[PATH_MAX];
string prefixPath = getenv(ENV_VAR_PREFIX_PATH);
prefixPath += "/bin/dmtcp_launch";
JASSERT(realpath(prefixPath.c_str(), buf) != NULL) (prefixPath);
prefixPath = buf;
string programPath = jalib::Filesystem::GetProgramPath();
JASSERT(prefixPath == programPath) (prefixPath) (programPath);
}
dmtcp::Util::setTmpDir(getenv(ENV_VAR_TMPDIR));
dmtcp::UniquePid::ThisProcess(true);
dmtcp::Util::initializeLogFile();
#ifdef FORKED_CHECKPOINTING
/* When this is robust, add --forked-checkpointing option on command-line,
* with #ifdef FORKED_CHECKPOINTING around the option, change default of
* configure.ac, dmtcp/configure.ac, to enable, and change them
* from enable-forked... to disable-...
*/
setenv(ENV_VAR_FORKED_CKPT, "1", 1);
#endif
// This code will go away when zero-mapped pages are implemented in MTCP.
struct rlimit rlim;
getrlimit(RLIMIT_STACK, &rlim);
if (rlim.rlim_cur > 256*1024*1024 && rlim.rlim_cur != RLIM_INFINITY)
JASSERT_STDERR <<
"*** WARNING: RLIMIT_STACK > 1/4 GB. This causes each thread to"
"\n*** receive a 1/4 GB stack segment. Checkpoint/restart will be slow,"
"\n*** and will potentially break if many threads are created."
"\n*** Suggest setting (sh/bash): ulimit -s 10000"
"\n*** (csh/tcsh): limit stacksize 10000"
"\n*** prior to using DMTCP. (This will be fixed in the future, when"
"\n*** DMTCP supports restoring zero-mapped pages.)\n\n\n" ;
// Remove this when zero-mapped pages are supported. For segments with
// no file backing: Start with 4096 (page) offset and keep doubling offset
// until finding region of memory segment with many zeroes.
// Then mark as CS_ZERO_PAGES in MTCP instead of CS_RESTORE (or mark
// entire segment as CS_ZERO_PAGES and then overwrite with CS_RESTORE
// region for portion to be read back from checkpoint image.
// For CS_ZERO_PAGES region, mmap // on restart, but don't write in zeroes.
// Also, after checkpointing segment, munmap zero pages, and mmap them again.
// Don't try to find all pages. The above strategy may increase
// the non-zero-mapped mapped pages to no more than double the actual
// non-zero region (assuming that the zero-mapped pages are contiguous).
// - Gene
testMatlab(argv[0]);
testJava(argv); // Warn that -Xmx flag needed to limit virtual memory size
// If libdmtcp.so is in standard search path and _also_ has setgid access,
// then LD_PRELOAD will work.
// Otherwise, it will only work if the application does not use setuid and
// setgid access. So, we test // if the application does not use
// setuid/setgid. (See 'man ld.so')
// FIXME: ALSO DO THIS FOR execwrappers.cpp:dmtcpPrepareForExec()
// Should pass libdmtcp.so path, and let testSetuid determine
// if setgid is set for it. If so, no problem: continue.
// If not, call testScreen() and adapt 'screen' to run using
// Util::patchArgvIfSetuid(argv[0], argv, &newArgv) (which shouldn't
// will just modify argv[0] to point to /tmp/dmtcp-USER@HOST/screen
// and other modifications: doesn't need newArgv).
// If it's not 'screen' and if no setgid for libdmtcp.so, then testSetuid
// should issue the warning, unset our LD_PRELOAD, and hope for the best.
// A program like /usr/libexec/utempter/utempter (Fedora path)
// is short-lived and can be safely run. Ideally, we should
// disable checkpoints while utempter is running, and enable checkpoints
// when utempter finishes. See possible model at
// execwrappers.cpp:execLibProcessAndExit(), since the same applies
// to running /lib/libXXX.so for running libraries as executables.
if (testSetuid(argv[0])) {
char **newArgv;
// THIS NEXT LINE IS DANGEROUS. MOST setuid PROGRAMS CAN'T RUN UNPRIVILEGED
dmtcp::Util::patchArgvIfSetuid(argv[0], argv, &newArgv);
argv = newArgv;
};
if (argc > 0) {
JTRACE("dmtcp_launch starting new program:")(argv[0]);
}
//set up CHECKPOINT_DIR
if(getenv(ENV_VAR_CHECKPOINT_DIR) == NULL){
const char* ckptDir = get_current_dir_name();
if(ckptDir != NULL ){
//copy to private buffer
static dmtcp::string _buf = ckptDir;
ckptDir = _buf.c_str();
}else{
ckptDir=".";
}
setenv ( ENV_VAR_CHECKPOINT_DIR, ckptDir, 0 );
JTRACE("setting " ENV_VAR_CHECKPOINT_DIR)(ckptDir);
}
if ( checkpointOpenFiles )
setenv( ENV_VAR_CKPT_OPEN_FILES, "1", 0 );
else
unsetenv( ENV_VAR_CKPT_OPEN_FILES);
bool isElf, is32bitElf;
if (dmtcp::Util::elfType(argv[0], &isElf, &is32bitElf) == -1) {
// Couldn't read argv_buf
// FIXME: This could have been a symbolic link. Don't issue an error,
// unless we're sure that the executable is not readable.
JASSERT_STDERR <<
"*** ERROR: Executable to run w/ DMTCP appears not to be readable,\n"
"*** or no such executable in path.\n\n"
<< argv[0] << "\n";
exit(DMTCP_FAIL_RC);
} else {
testStaticallyLinked(argv[0]);
}
if (getenv("DISPLAY") != NULL) {
setenv("ORIG_DISPLAY", getenv("DISPLAY"), 1);
// UNSET DISPLAY environment variable.
unsetenv("DISPLAY");
}
if( explicitSrun ){
setenv(ENV_VAR_EXPLICIT_SRUN, "1", 1);
}
// FIXME: Unify this code with code prior to execvp in execwrappers.cpp
// Can use argument to dmtcpPrepareForExec() or getenv("DMTCP_...")
// from DmtcpWorker constructor, to distinguish the two cases.
dmtcp::Util::adjustRlimitStack();
// Set DLSYM_OFFSET env var(s).
dmtcp::Util::prepareDlsymWrapper();
DmtcpUniqueProcessId compId;
CoordinatorInfo coordInfo;
struct in_addr localIPAddr;
CoordinatorAPI::instance().connectToCoordOnStartup(allowedModes, argv[0],
&compId, &coordInfo,
&localIPAddr);
Util::writeCoordPortToFile(getenv(ENV_VAR_NAME_PORT), thePortFile.c_str());
/* We need to initialize SharedData here to make sure that it is
* initialized with the correct coordinator timestamp. The coordinator
* timestamp is updated only during postCkpt callback. However, the
* SharedData area may be initialized earlier (for example, while
* recreating threads), causing it to use *older* timestamp.
*/
SharedData::initialize(Util::getTmpDir().c_str(), &compId, &coordInfo,
&localIPAddr);
setLDPreloadLibs(is32bitElf);
//run the user program
char **newArgv = NULL;
if (testScreen(argv, &newArgv))
execvp ( newArgv[0], newArgv );
else
execvp ( argv[0], argv );
//should be unreachable
JASSERT_STDERR <<
"ERROR: Failed to exec(\"" << argv[0] << "\"): " << JASSERT_ERRNO << "\n"
<< "Perhaps it is not in your $PATH?\n"
<< "See `dmtcp_launch --help` for usage.\n";
//fprintf(stderr, theExecFailedMsg, argv[0], JASSERT_ERRNO);
return -1;
}