/** Return an unused directory in the execution pool directory. Set virtualExecDir */
public static String createVirtualExecDir() {
if (useStandardExecPoolDirStrategy) {
// Assume we are in the run directory, so set the standard paths
execPoolDir = new File(SysInfoUtils.getcwd(), "state/execs").toString();
actualExecPoolDir =
new File(SysInfoUtils.getcwd(), "state/hosts/" + SysInfoUtils.getShortHostName())
.toString();
if (!new File(actualExecPoolDir).isDirectory()) actualExecPoolDir = null;
}
if (!StrUtils.isEmpty(execPoolDir) && !new File(execPoolDir).isDirectory())
throw Exceptions.bad("Execution pool directory '" + execPoolDir + "' doesn't exist");
if (!StrUtils.isEmpty(actualExecPoolDir) && !new File(actualExecPoolDir).isDirectory())
throw Exceptions.bad(
"Actual execution pool directory '" + actualExecPoolDir + "' doesn't exist");
if (!StrUtils.isEmpty(execDir)) { // Use specified execDir
boolean exists = new File(execDir).isDirectory();
if (exists && !overwriteExecDir)
throw Exceptions.bad("Directory %s already exists and overwrite flag is false", execDir);
if (!exists) mkdirHard(new File(execDir));
else {
// This part looks at actualExecPoolDir
// This case is overwriting an existing execution directory, which
// happens when we are executing a thunk. We have to be careful here
// because the actual symlinked directory that was created when thunking
// might be using a different actualPoolDir. If this happens, we need
// to move the actual thunked symlinked directory into the actual
// execution pool directory requested. In fact, we always do this for simplicity.
String oldActualExecDir = Utils.systemGetStringOutputEasy("readlink " + execDir);
if (oldActualExecDir == null) { // Not symlink
if (!StrUtils.isEmpty(actualExecPoolDir))
throw Exceptions.bad(
"The old execution directory was not created with actualExecPoolDir but now we want an actualExecPoolDir");
// Do nothing, just use the directory as is
} else { // Symlink
oldActualExecDir = oldActualExecDir.trim();
if (StrUtils.isEmpty(actualExecPoolDir))
throw Exceptions.bad(
"The old execution directory was created with actualExecPoolDir but now we don't want an actualExecPoolDir");
// Note that now the execution numbers might not correspond between the
// actual and virtual execution pool directories.
File newActualExecDir = null;
for (int i = 0; ; i++) {
newActualExecDir = new File(actualExecPoolDir, i + "a.exec");
if (!newActualExecDir.exists()) break;
}
// Move the old directory to the new directory
Utils.systemHard(String.format("mv %s %s", oldActualExecDir, newActualExecDir));
// Update the symlink (execDir -> newActualExecDir)
Utils.systemHard(
String.format("ln -sf %s %s", newActualExecDir.getAbsolutePath(), execDir));
}
}
return virtualExecDir = execDir;
}
// execDir hasn't been specified, so we need to pick one from a pool directory
// execPoolDir must exist; actualExecPoolDir is optional
// Get a list of files that already exists
Set<String> files = new HashSet<String>();
for (String f : new File(execPoolDir).list()) files.add(f);
// Go through and pick out a file that doesn't exist
int numFailures = 0;
for (int i = 0; numFailures < 3; i++) {
// Either the virtual file (a link) or the actual file
File f = new File(execPoolDir, i + ".exec");
// Actual file
File g =
StrUtils.isEmpty(actualExecPoolDir) ? null : new File(actualExecPoolDir, i + ".exec");
if (!files.contains(i + ".exec") && (g == null || !g.exists())) {
if (g == null || g.equals(f)) {
mkdirHard(f);
return virtualExecDir = f.toString();
}
// Create symlink before mkdir to try to reserve the name and avoid race conditions
if (Utils.createSymLink(g.getAbsolutePath(), f.getAbsolutePath())) {
mkdirHard(g);
return virtualExecDir = f.toString();
}
// Probably because someone else already linked to it
// in the race condition: so try again
stderr.println("Cannot create symlink from " + f + " to " + g);
numFailures++;
}
}
throw Exceptions.bad("Failed many times to create execution directory");
}
public static void linkFileFromExec(String file, String realFileName) {
if (StrUtils.isEmpty(realFileName) || StrUtils.isEmpty(file)) return;
File f = new File(realFileName);
Utils.createSymLink(getFile(file), f.getAbsolutePath());
}
public static synchronized void printOutputMap(String path) {
if (StrUtils.isEmpty(path)) return;
// First write to a temporary directory and then rename the file
String tmpPath = path + ".tmp";
if (outputMap.printEasy(tmpPath)) new File(tmpPath).renameTo(new File(path));
}
// Get the path of the file (in the execution directory)
public static String getFile(String file) {
if (StrUtils.isEmpty(virtualExecDir)) return null;
if (StrUtils.isEmpty(file)) return null;
return new File(virtualExecDir, file).toString();
}