/** * Reads one start command from the command socket. If successful, a child is forked and a {@link * ZygoteInit.MethodAndArgsCaller} exception is thrown in that child while in the parent process, * the method returns normally. On failure, the child is not spawned and messages are printed to * the log and stderr. Returns a boolean status value indicating whether an end-of-file on the * command socket has been encountered. * * @return false if command socket should continue to be read from, or true if an end-of-file has * been encountered. * @throws ZygoteInit.MethodAndArgsCaller trampoline to invoke main() method in child process */ boolean runOnce() throws ZygoteInit.MethodAndArgsCaller { String args[]; Arguments parsedArgs = null; FileDescriptor[] descriptors; try { args = readArgumentList(); descriptors = mSocket.getAncillaryFileDescriptors(); } catch (IOException ex) { Log.w(TAG, "IOException on command socket " + ex.getMessage()); closeSocket(); return true; } if (args == null) { // EOF reached. closeSocket(); return true; } /** the stderr of the most recent request, if avail */ PrintStream newStderr = null; if (descriptors != null && descriptors.length >= 3) { newStderr = new PrintStream(new FileOutputStream(descriptors[2])); } int pid = -1; FileDescriptor childPipeFd = null; FileDescriptor serverPipeFd = null; try { parsedArgs = new Arguments(args); applyUidSecurityPolicy(parsedArgs, peer, peerSecurityContext); applyRlimitSecurityPolicy(parsedArgs, peer, peerSecurityContext); applyCapabilitiesSecurityPolicy(parsedArgs, peer, peerSecurityContext); applyInvokeWithSecurityPolicy(parsedArgs, peer, peerSecurityContext); applyseInfoSecurityPolicy(parsedArgs, peer, peerSecurityContext); applyDebuggerSystemProperty(parsedArgs); applyInvokeWithSystemProperty(parsedArgs); int[][] rlimits = null; if (parsedArgs.rlimits != null) { rlimits = parsedArgs.rlimits.toArray(intArray2d); } if (parsedArgs.runtimeInit && parsedArgs.invokeWith != null) { FileDescriptor[] pipeFds = Libcore.os.pipe(); childPipeFd = pipeFds[1]; serverPipeFd = pipeFds[0]; ZygoteInit.setCloseOnExec(serverPipeFd, true); } pid = Zygote.forkAndSpecialize( parsedArgs.uid, parsedArgs.gid, parsedArgs.gids, parsedArgs.debugFlags, rlimits, parsedArgs.mountExternal, parsedArgs.seInfo, parsedArgs.niceName); } catch (IOException ex) { logAndPrintError(newStderr, "Exception creating pipe", ex); } catch (ErrnoException ex) { logAndPrintError(newStderr, "Exception creating pipe", ex); } catch (IllegalArgumentException ex) { logAndPrintError(newStderr, "Invalid zygote arguments", ex); } catch (ZygoteSecurityException ex) { logAndPrintError(newStderr, "Zygote security policy prevents request: ", ex); } try { if (pid == 0) { // in child IoUtils.closeQuietly(serverPipeFd); serverPipeFd = null; handleChildProc(parsedArgs, descriptors, childPipeFd, newStderr); // should never get here, the child is expected to either // throw ZygoteInit.MethodAndArgsCaller or exec(). return true; } else { // in parent...pid of < 0 means failure IoUtils.closeQuietly(childPipeFd); childPipeFd = null; return handleParentProc(pid, descriptors, serverPipeFd, parsedArgs); } } finally { IoUtils.closeQuietly(childPipeFd); IoUtils.closeQuietly(serverPipeFd); } }