--- /dev/null
+package org.xwt.mips;
+
+import org.xwt.mips.util.*;
+import java.io.*;
+import java.util.*;
+
+public abstract class UnixRuntime extends Runtime {
+ /** The pid of this "process" */
+ private int pid;
+ private int ppid;
+ protected int getPid() { return pid; }
+
+ /** processes filesystem */
+ private FS fs;
+ public FS getFS() { return fs; }
+ public void setFS(FS fs) {
+ if(state >= RUNNING) throw new IllegalStateException("Can't change fs while process is running");
+ this.fs = fs;
+ }
+
+ /** proceses current working directory */
+ private String cwd;
+
+ /* Static stuff */
+ // FEATURE: Most of this is O(n) or worse - fix it
+ private final Object waitNotification = new Object();
+ private final static int MAX_TASKS = 256;
+ private final static UnixRuntime[] tasks = new UnixRuntime[MAX_TASKS];
+ private static int addTask(UnixRuntime rt) {
+ synchronized(tasks) {
+ for(int i=1;i<MAX_TASKS;i++) {
+ if(tasks[i] == null) {
+ tasks[i] = rt;
+ rt.pid = i;
+ return i;
+ }
+ }
+ return -1;
+ }
+ }
+ private static void removeTask(UnixRuntime rt) {
+ synchronized(tasks) {
+ for(int i=1;i<MAX_TASKS;i++)
+ if(tasks[i] == rt) { tasks[i] = null; break; }
+ }
+ }
+
+ public UnixRuntime(int pageSize, int totalPages, boolean allowEmptyPages) {
+ super(pageSize,totalPages,allowEmptyPages);
+
+ HostFS root = new HostFS();
+ fs = new UnixOverlayFS(root);
+
+ String dir = root.hostCWD();
+ try {
+ chdir(dir == null ? "/" : dir);
+ } catch(FileNotFoundException e) {
+ e.printStackTrace();
+ cwd = "/";
+ }
+ }
+
+ private static String posixTZ() {
+ StringBuffer sb = new StringBuffer();
+ TimeZone zone = TimeZone.getDefault();
+ int off = zone.getRawOffset() / 1000;
+ sb.append(zone.getDisplayName(false,TimeZone.SHORT));
+ if(off > 0) sb.append("-");
+ else off = -off;
+ sb.append(off/3600); off = off%3600;
+ if(off > 0) sb.append(":").append(off/60); off=off%60;
+ if(off > 0) sb.append(":").append(off);
+ if(zone.useDaylightTime())
+ sb.append(zone.getDisplayName(true,TimeZone.SHORT));
+ return sb.toString();
+ }
+
+ private static boolean envHas(String key,String[] environ) {
+ for(int i=0;i<environ.length;i++)
+ if(environ[i]!=null && environ[i].startsWith(key + "=")) return true;
+ return false;
+ }
+
+ protected String[] createEnv(String[] extra) {
+ String[] defaults = new String[5];
+ int n=0;
+ if(extra == null) extra = new String[0];
+ if(!envHas("USER",extra) && getSystemProperty("user.name") != null)
+ defaults[n++] = "USER=" + getSystemProperty("user.name");
+ if(!envHas("HOME",extra) && getSystemProperty("user.name") != null)
+ defaults[n++] = "HOME=" + getSystemProperty("user.home");
+ if(!envHas("SHELL",extra)) defaults[n++] = "SHELL=/bin/sh";
+ if(!envHas("TERM",extra)) defaults[n++] = "TERM=vt100";
+ if(!envHas("TZ",extra)) defaults[n++] = "TZ=" + posixTZ();
+ String[] env = new String[extra.length+n];
+ for(int i=0;i<n;i++) env[i] = defaults[i];
+ for(int i=0;i<extra.length;i++) env[n++] = extra[i];
+ return env;
+ }
+
+ protected void _start() {
+ if(addTask(this) < 0) throw new Error("Task list full");
+ }
+
+ protected void _exit() {
+ synchronized(tasks) {
+ if(ppid == 0) removeTask(this);
+ for(int i=0;i<MAX_TASKS;i++) {
+ if(tasks[i] != null && tasks[i].ppid == pid) {
+ if(tasks[i].state == DONE) removeTask(tasks[i]);
+ else tasks[i].ppid = 0;
+ }
+ }
+ state = DONE;
+ if(ppid != 0) synchronized(tasks[ppid].waitNotification) { tasks[ppid].waitNotification.notify(); }
+ }
+ }
+
+ protected int syscall(int syscall, int a, int b, int c, int d) {
+ switch(syscall) {
+ case SYS_kill: return sys_kill(a,b);
+ case SYS_fork: return sys_fork();
+ case SYS_pipe: return sys_pipe(a);
+ case SYS_dup2: return sys_dup2(a,b);
+ case SYS_waitpid: return sys_waitpid(a,b,c);
+ case SYS_stat: return sys_stat(a,b);
+ case SYS_mkdir: return sys_mkdir(a,b);
+ case SYS_getcwd: return sys_getcwd(a,b);
+ case SYS_chdir: return sys_chdir(a);
+
+ default: return super.syscall(syscall,a,b,c,d);
+ }
+ }
+
+ protected FD open(String path, int flags, int mode) throws IOException { return fs.open(cleanupPath(path),flags,mode); }
+
+ // FEATURE: Allow simple, broken signal delivery to other processes
+ // (check if a signal was delivered before and after syscalls)
+ // FEATURE: Implement raise() in terms of call("raise",...) - kinda cheap, but it keeps the complexity in newlib
+ /** The kill syscall.
+ SIGSTOP, SIGTSTO, SIGTTIN, and SIGTTOUT pause the process.
+ SIGCONT, SIGCHLD, SIGIO, and SIGWINCH are ignored.
+ Anything else terminates the process. */
+ private int sys_kill(int pid, int signal) {
+ // This will only be called by raise() in newlib to invoke the default handler
+ // We don't have to worry about actually delivering the signal
+ if(pid != pid) return -ESRCH;
+ if(signal < 0 || signal >= 32) return -EINVAL;
+ switch(signal) {
+ case 0: return 0;
+ case 17: // SIGSTOP
+ case 18: // SIGTSTP
+ case 21: // SIGTTIN
+ case 22: // SIGTTOU
+ state = PAUSED;
+ break;
+ case 19: // SIGCONT
+ case 20: // SIGCHLD
+ case 23: // SIGIO
+ case 28: // SIGWINCH
+ break;
+ default: {
+ String msg = "Terminating on signal: " + signal + "\n";
+ exitStatus = 1;
+ state = DONE;
+ if(fds[2]==null) {
+ System.out.print(msg);
+ } else {
+ try {
+ byte[] b = getBytes(msg);
+ fds[2].write(b,0,b.length);
+ }
+ catch(IOException e) { /* ignore */ }
+ }
+ }
+ }
+ return 0;
+ }
+
+ private int sys_waitpid(int pid, int statusAddr, int options) {
+ final int WNOHANG = 1;
+ if((options & ~(WNOHANG)) != 0) return -EINVAL;
+ if(pid !=-1 && (pid <= 0 || pid >= MAX_TASKS)) return -ECHILD;
+ for(;;) {
+ synchronized(tasks) {
+ UnixRuntime task = null;
+ if(pid == -1) {
+ for(int i=0;i<MAX_TASKS;i++) {
+ if(tasks[i] != null && tasks[i].ppid == this.pid && tasks[i].state == DONE) {
+ task = tasks[i];
+ break;
+ }
+ }
+ } else if(tasks[pid] != null && tasks[pid].ppid == this.pid && tasks[pid].state == DONE) {
+ task = tasks[pid];
+ }
+
+ if(task != null) {
+ removeTask(task);
+ try {
+ if(statusAddr!=0) memWrite(statusAddr,task.exitStatus()<<8);
+ } catch(FaultException e) {
+ return -EFAULT;
+ }
+
+ return task.pid;
+ }
+ }
+ if((options&WNOHANG)!=0) return 0;
+ synchronized(waitNotification) {
+ try { waitNotification.wait(); } catch(InterruptedException e) { throw new Error(e); }
+ }
+ }
+ }
+
+ // Great ugliness lies within.....
+ private int sys_fork() {
+ CPUState state = getCPUState();
+ int sp = state.r[SP];
+ final UnixRuntime r;
+ try {
+ r = (UnixRuntime) getClass().newInstance();
+ } catch(Exception e) {
+ System.err.println(e);
+ return -ENOMEM;
+ }
+ int child_pid = addTask(r);
+ if(child_pid < 0) return -ENOMEM;
+
+ r.ppid = pid;
+ r.brkAddr = brkAddr;
+ r.fds = new FD[OPEN_MAX];
+ for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) r.fds[i] = fds[i].dup();
+ r.cwd = cwd;
+ r.fs = fs;
+ for(int i=0;i<TOTAL_PAGES;i++) {
+ if(readPages[i] == null) continue;
+ if(isEmptyPage(writePages[i])) {
+ r.readPages[i] = r.writePages[i] = writePages[i];
+ } else if(writePages[i] != null) {
+ r.readPages[i] = r.writePages[i] = new int[PAGE_WORDS];
+ if(STACK_BOTTOM == 0 || i*PAGE_SIZE < STACK_BOTTOM || i*PAGE_SIZE >= sp-PAGE_SIZE*2)
+ System.arraycopy(writePages[i],0,r.writePages[i],0,PAGE_WORDS);
+ } else {
+ r.readPages[i] = r.readPages[i];
+ }
+ }
+ state.r[V0] = 0;
+ state.pc += 4;
+ r.setCPUState(state);
+ r.state = PAUSED;
+
+ new Thread() {
+ public void run() {
+ try {
+ while(!r.execute());
+ } catch(Exception e) {
+ System.err.println("Forked process threw exception: ");
+ e.printStackTrace();
+ }
+ }
+ }.start();
+
+ return child_pid;
+ }
+
+ private int sys_pipe(int addr) {
+ PipedOutputStream writerStream = new PipedOutputStream();
+ PipedInputStream readerStream;
+ try {
+ readerStream = new PipedInputStream(writerStream);
+ } catch(IOException e) {
+ return -EIO;
+ }
+ FD reader = new InputStreamFD(readerStream);
+ FD writer = new OutputStreamFD(writerStream);
+ int fd1 = addFD(reader);
+ if(fd1 < 0) return -ENFILE;
+ int fd2 = addFD(writer);
+ if(fd2 < 0) { closeFD(fd1); return -ENFILE; }
+ try {
+ memWrite(addr,fd1);
+ memWrite(addr+4,fd2);
+ } catch(FaultException e) {
+ closeFD(fd1);
+ closeFD(fd2);
+ return -EFAULT;
+ }
+ return 0;
+ }
+
+ private int sys_dup2(int oldd, int newd) {
+ if(oldd == newd) return 0;
+ if(oldd < 0 || oldd >= OPEN_MAX) return -EBADFD;
+ if(newd < 0 || newd >= OPEN_MAX) return -EBADFD;
+ if(fds[oldd] == null) return -EBADFD;
+ if(fds[newd] != null) fds[newd].close();
+ fds[newd] = fds[oldd].dup();
+ return 0;
+ }
+
+ private int sys_stat(int cstring, int addr) {
+ try {
+ String path = cleanupPath(cstring(cstring));
+ return stat(fs.stat(path),addr);
+ }
+ catch(ErrnoException e) { return -e.errno; }
+ catch(FileNotFoundException e) {
+ if(e.getMessage() != null && e.getMessage().indexOf("Permission denied") >= 0) return -EACCES;
+ return -ENOENT;
+ }
+ catch(IOException e) { return -EIO; }
+ catch(FaultException e) { return -EFAULT; }
+ }
+
+
+ private int sys_mkdir(int cstring, int mode) {
+ try {
+ fs.mkdir(cleanupPath(cstring(cstring)));
+ return 0;
+ }
+ catch(ErrnoException e) { return -e.errno; }
+ catch(FileNotFoundException e) { return -ENOENT; }
+ catch(IOException e) { return -EIO; }
+ catch(FaultException e) { return -EFAULT; }
+ }
+
+
+ private int sys_getcwd(int addr, int size) {
+ byte[] b = getBytes(cwd);
+ if(size == 0) return -EINVAL;
+ if(size < b.length+1) return -ERANGE;
+ if(!new File(cwd).exists()) return -ENOENT;
+ try {
+ copyout(b,addr,b.length);
+ memset(addr+b.length+1,0,1);
+ return addr;
+ } catch(FaultException e) {
+ return -EFAULT;
+ }
+ }
+
+ private int sys_chdir(int addr) {
+ try {
+ String path = cleanupPath(cstring(addr));
+ System.err.println("Chdir: " + cstring(addr) + " -> " + path + " pwd: " + cwd);
+ if(fs.stat(path).type() != FStat.S_IFDIR) return -ENOTDIR;
+ cwd = path;
+ System.err.println("Now: " + cwd);
+ return 0;
+ }
+ catch(ErrnoException e) { return -e.errno; }
+ catch(FileNotFoundException e) { return -ENOENT; }
+ catch(IOException e) { return -EIO; }
+ catch(FaultException e) { return -EFAULT; }
+ }
+
+ public void chdir(String dir) throws FileNotFoundException {
+ if(state >= RUNNING) throw new IllegalStateException("Can't chdir while process is running");
+ try {
+ dir = cleanupPath(dir);
+ if(fs.stat(dir).type() != FStat.S_IFDIR) throw new FileNotFoundException();
+ } catch(IOException e) {
+ throw new FileNotFoundException();
+ }
+ cwd = dir;
+ }
+
+ public abstract static class FS {
+ public FD open(String path, int flags, int mode) throws IOException { throw new FileNotFoundException(); }
+ public FStat stat(String path) throws IOException { throw new FileNotFoundException(); }
+ public void mkdir(String path) throws IOException { throw new ErrnoException(ENOTDIR); }
+
+ public static FD directoryFD(String[] files, int hashCode) throws IOException {
+ ByteArrayOutputStream bos = new ByteArrayOutputStream();
+ DataOutputStream dos = new DataOutputStream(bos);
+ for(int i=0;i<files.length;i++) {
+ byte[] b = getBytes(files[i]);
+ int inode = (files[i].hashCode() ^ hashCode) & 0xfffff;
+ dos.writeInt(inode);
+ dos.writeInt(b.length);
+ dos.write(b,0,b.length);
+ }
+ final byte[] data = bos.toByteArray();
+ return new SeekableFD(new SeekableByteArray(data,false),RD_ONLY) {
+ protected FStat _fstat() { return new FStat() {
+ public int length() { return data.length; }
+ public int type() { return S_IFDIR; }
+ }; }
+ };
+ }
+ }
+
+ public static void main(String[] args) throws Exception {
+ UnixRuntime rt = new Interpreter();
+ rt.cwd = getSystemProperty("user.dir");
+ BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+ String line;
+ while((line = br.readLine()) != null) {
+ System.out.println("[" + rt.cleanupPath(line) + "]");
+ }
+ }
+
+
+ private static boolean needsCleanup(String path) {
+ if(path.indexOf("//") != -1) return true;
+ if(path.indexOf('.') != -1) {
+ if(path.length() == 1) return true;
+ if(path.equals("..")) return true;
+ if(path.startsWith("./") || path.indexOf("/./") != -1 || path.endsWith("/.")) return true;
+ if(path.startsWith("../") || path.indexOf("/../") != -1 || path.endsWith("/..")) return true;
+ }
+ return false;
+ }
+
+ // FIXME: This is probably still buggy
+ // FEATURE: Remove some of the "should never happen checks"
+ protected String cleanupPath(String p) throws ErrnoException {
+ if(p.length() == 0) throw new ErrnoException(ENOENT);
+ if(needsCleanup(p)) {
+ char[] in = p.toCharArray();
+ char[] out;
+ int outp ;
+ if(in[0] == '/') {
+ out = new char[in.length];
+ outp = 0;
+ } else {
+ out = new char[cwd.length() + in.length + 1];
+ outp = cwd.length();
+ for(int i=0;i<outp;i++) out[i] = cwd.charAt(i);
+ if(outp == 0 || out[0] != '/') throw new Error("should never happen");
+ }
+ int inLength = in.length;
+ int inp = 0;
+ while(inp<inLength) {
+ if(inp == 0 || in[inp] == '/') {
+ while(inp < inLength && in[inp] == '/') inp++;
+ if(inp == inLength) break;
+ if(in[inp] == '.') {
+ if(inp+1 == inLength) break;
+ if(in[inp+1] == '.' && (inp+2 == inLength || in[inp+2] == '/')) {
+ inp+=2;
+ if(outp == 0) continue;
+ do { outp--; } while(outp > 0 && out[outp] != '/');
+ } else if(in[inp+1] == '/') {
+ inp++;
+ } else {
+ out[outp++] = '/';
+ }
+ } else {
+ out[outp++] = '/';
+ out[outp++] = in[inp++];
+ }
+ } else {
+ out[outp++] = in[inp++];
+ }
+ }
+ if(outp == 0) out[outp++] = '/';
+ return new String(out,0,outp);
+ } else {
+ if(p.startsWith("/")) return p;
+ StringBuffer sb = new StringBuffer(cwd);
+ if(!cwd.equals("/")) sb.append('/');
+ return sb.append(p).toString();
+ }
+ }
+
+ // FEATURE: Probably should make this more general - support mountpoints, etc
+ public class UnixOverlayFS extends FS {
+ private final FS root;
+ private final FS dev = new DevFS();
+ public UnixOverlayFS(FS root) {
+ this.root = root;
+ }
+ private String devPath(String path) {
+ if(path.startsWith("/dev")) {
+ if(path.length() == 4) return "/";
+ if(path.charAt(4) == '/') return path.substring(4);
+ }
+ return null;
+ }
+ public FD open(String path, int flags, int mode) throws IOException{
+ String dp = devPath(path);
+ return dp == null ? root.open(path,flags,mode) : dev.open(dp,flags,mode);
+ }
+ public FStat stat(String path) throws IOException {
+ String dp = devPath(path);
+ return dp == null ? root.stat(path) : dev.stat(dp);
+ }
+ public void mkdir(String path) throws IOException {
+ String dp = devPath(path);
+ if(dp == null) root.mkdir(path);
+ else dev.mkdir(dp);
+ }
+ }
+
+ // FIXME: This is totally broken on non-unix hosts - need to do some kind of cygwin type mapping
+ public static class HostFS extends FS {
+ public static String fixPath(String path) throws FileNotFoundException {
+ return path;
+ }
+
+ public String hostCWD() {
+ return getSystemProperty("user.dir");
+ }
+
+ // FEATURE: This shares a lot with Runtime.open
+ public FD open(String path, int flags, int mode) throws IOException {
+ path = fixPath(path);
+ final File f = new File(path);
+ // NOTE: createNewFile is a Java2 function
+ if((flags & (O_EXCL|O_CREAT)) == (O_EXCL|O_CREAT))
+ if(!f.createNewFile()) throw new ErrnoException(EEXIST);
+ if(!f.exists() && (flags&O_CREAT) == 0) return null;
+ if(f.isDirectory()) {
+ if((flags&3)!=RD_ONLY) throw new ErrnoException(EACCES);
+ return directoryFD(f.list(),path.hashCode());
+ }
+ final SeekableFile sf = new SeekableFile(path,(flags&3)!=RD_ONLY);
+ if((flags&O_TRUNC)!=0) sf.setLength(0);
+ return new SeekableFD(sf,mode) {
+ protected FStat _fstat() { return new HostFStat(f) {
+ public int size() {
+ try { return sf.length(); } catch(IOException e) { return 0; }
+ }
+ };}
+ };
+ }
+
+ public FStat stat(String path) throws FileNotFoundException {
+ File f = new File(fixPath(path));
+ if(!f.exists()) throw new FileNotFoundException();
+ return new HostFStat(f);
+ }
+
+ public void mkdir(String path) throws IOException {
+ File f = new File(fixPath(path));
+ if(f.exists() && f.isDirectory()) throw new ErrnoException(EEXIST);
+ if(f.exists()) throw new ErrnoException(ENOTDIR);
+ File parent = f.getParentFile();
+ if(parent!=null && (!parent.exists() || !parent.isDirectory())) throw new ErrnoException(ENOTDIR);
+ if(!f.mkdir()) throw new ErrnoException(EIO);
+ }
+ }
+
+ private static class DevFStat extends FStat {
+ public int dev() { return 1; }
+ public int mode() { return 0666; }
+ public int type() { return S_IFCHR; }
+ public int nlink() { return 1; }
+ }
+ private static FD devZeroFD = new FD() {
+ public boolean readable() { return true; }
+ public boolean writable() { return true; }
+ public int read(byte[] a, int off, int length) { Arrays.fill(a,off,off+length,(byte)0); return length; }
+ public int write(byte[] a, int off, int length) { return length; }
+ public int seek(int n, int whence) { return 0; }
+ public FStat _fstat() { return new DevFStat(); }
+ };
+ private static FD devNullFD = new FD() {
+ public boolean readable() { return true; }
+ public boolean writable() { return true; }
+ public int read(byte[] a, int off, int length) { return 0; }
+ public int write(byte[] a, int off, int length) { return length; }
+ public int seek(int n, int whence) { return 0; }
+ public FStat _fstat() { return new DevFStat(); }
+ };
+
+ public class DevFS extends FS {
+ public FD open(String path, int mode, int flags) throws IOException {
+ if(path.equals("/null")) return devNullFD;
+ if(path.equals("/zero")) return devZeroFD;
+ if(path.startsWith("/fd/")) {
+ int n;
+ try {
+ n = Integer.parseInt(path.substring(4));
+ } catch(NumberFormatException e) {
+ throw new FileNotFoundException();
+ }
+ if(n < 0 || n >= OPEN_MAX) throw new FileNotFoundException();
+ if(fds[n] == null) throw new FileNotFoundException();
+ return fds[n].dup();
+ }
+ if(path.equals("/fd")) {
+ int count=0;
+ for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) count++;
+ String[] files = new String[count];
+ count = 0;
+ for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) files[count++] = Integer.toString(i);
+ return directoryFD(files,hashCode());
+ }
+ if(path.equals("/")) {
+ String[] files = { "null", "zero", "fd" };
+ return directoryFD(files,hashCode());
+ }
+ throw new FileNotFoundException();
+ }
+
+ public FStat stat(String path) throws IOException {
+ if(path.equals("/null")) return devNullFD.fstat();
+ if(path.equals("/zero")) return devZeroFD.fstat();
+ if(path.startsWith("/fd/")) {
+ int n;
+ try {
+ n = Integer.parseInt(path.substring(4));
+ } catch(NumberFormatException e) {
+ throw new FileNotFoundException();
+ }
+ if(n < 0 || n >= OPEN_MAX) throw new FileNotFoundException();
+ if(fds[n] == null) throw new FileNotFoundException();
+ return fds[n].fstat();
+ }
+ if(path.equals("/fd")) return new FStat() { public int type() { return S_IFDIR; } public int mode() { return 0444; }};
+ if(path.equals("/")) return new FStat() { public int type() { return S_IFDIR; } public int mode() { return 0444; }};
+ throw new FileNotFoundException();
+ }
+
+ public void mkdir(String path) throws IOException { throw new ErrnoException(EACCES); }
+ }
+}