1 // Copyright 2000-2005 the Contributors, as shown in the revision logs.
2 // Licensed under the Apache Public Source License 2.0 ("the License").
3 // You may not use this file except in compliance with the License.
5 // Copyright 2003 Brian Alliet
6 // Based on org.xwt.imp.MIPS by Adam Megacz
7 // Portions Copyright 2003 Adam Megacz
9 package org.ibex.nestedvm;
11 import org.ibex.nestedvm.util.*;
14 public abstract class Runtime implements UsermodeConstants,Registers,Cloneable {
15 public static final String VERSION = "1.0";
17 /** True to write useful diagnostic information to stderr when things go wrong */
18 final static boolean STDERR_DIAG = true;
20 /** Number of bits to shift to get the page number (1<<<pageShift == pageSize) */
21 protected final int pageShift;
22 /** Bottom of region of memory allocated to the stack */
23 private final int stackBottom;
25 /** Readable main memory pages */
26 protected int[][] readPages;
27 /** Writable main memory pages.
28 If the page is writable writePages[x] == readPages[x]; if not writePages[x] == null. */
29 protected int[][] writePages;
31 /** The address of the end of the heap */
34 /** Number of guard pages to keep between the stack and the heap */
35 private static final int STACK_GUARD_PAGES = 4;
37 /** The last address the executable uses (other than the heap/stack) */
38 protected abstract int heapStart();
40 /** The program's entry point */
41 protected abstract int entryPoint();
43 /** The location of the _user_info block (or 0 is there is none) */
44 protected int userInfoBase() { return 0; }
45 protected int userInfoSize() { return 0; }
47 /** The location of the global pointer */
48 protected abstract int gp();
50 /** When the process started */
51 private long startTime;
53 /** Program is executing instructions */
54 public final static int RUNNING = 0; // Horrible things will happen if this isn't 0
55 /** Text/Data loaded in memory */
56 public final static int STOPPED = 1;
57 /** Prgram has been started but is paused */
58 public final static int PAUSED = 2;
59 /** Program is executing a callJava() method */
60 public final static int CALLJAVA = 3;
61 /** Program has exited (it cannot currently be restarted) */
62 public final static int EXITED = 4;
63 /** Program has executed a successful exec(), a new Runtime needs to be run (used by UnixRuntime) */
64 public final static int EXECED = 5;
66 /** The current state */
67 protected int state = STOPPED;
68 /** @see Runtime#state state */
69 public final int getState() { return state; }
71 /** The exit status if the process (only valid if state==DONE)
73 private int exitStatus;
74 public ExecutionException exitException;
76 /** Table containing all open file descriptors. (Entries are null if the fd is not in use */
77 FD[] fds; // package-private for UnixRuntime
78 boolean closeOnExec[];
80 /** Pointer to a SecurityManager for this process */
82 public void setSecurityManager(SecurityManager sm) { this.sm = sm; }
84 /** Pointer to a callback for the call_java syscall */
85 private CallJavaCB callJavaCB;
86 public void setCallJavaCB(CallJavaCB callJavaCB) { this.callJavaCB = callJavaCB; }
88 /** Temporary buffer for read/write operations */
89 private byte[] _byteBuf;
90 /** Max size of temporary buffer
91 @see Runtime#_byteBuf */
92 final static int MAX_CHUNK = 16*1024*1024 - 1024;
94 /** Subclasses should actually execute program in this method. They should continue
95 executing until state != RUNNING. Only syscall() can modify state. It is safe
96 to only check the state attribute after a call to syscall() */
97 protected abstract void _execute() throws ExecutionException;
99 /** Subclasses should return the address of the symbol <i>symbol</i> or -1 it it doesn't exits in this method
100 This method is only required if the call() function is used */
101 protected int lookupSymbol(String symbol) { return -1; }
103 /** Subclasses should populate a CPUState object representing the cpu state */
104 protected abstract void getCPUState(CPUState state);
106 /** Subclasses should set the CPUState to the state held in <i>state</i> */
107 protected abstract void setCPUState(CPUState state);
109 /** True to enabled a few hacks to better support the win32 console */
110 final static boolean win32Hacks;
113 String os = Platform.getProperty("os.name");
114 String prop = Platform.getProperty("nestedvm.win32hacks");
115 if(prop != null) { win32Hacks = Boolean.valueOf(prop).booleanValue(); }
116 else { win32Hacks = os != null && os.toLowerCase().indexOf("windows") != -1; }
119 protected Object clone() throws CloneNotSupportedException {
120 Runtime r = (Runtime) super.clone();
123 r.fds = new FD[OPEN_MAX];
124 for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) r.fds[i] = fds[i].dup();
125 int totalPages = writePages.length;
126 r.readPages = new int[totalPages][];
127 r.writePages = new int[totalPages][];
128 for(int i=0;i<totalPages;i++) {
129 if(readPages[i] == null) continue;
130 if(writePages[i] == null) r.readPages[i] = readPages[i];
131 else r.readPages[i] = r.writePages[i] = (int[])writePages[i].clone();
136 protected Runtime(int pageSize, int totalPages) { this(pageSize, totalPages,false); }
137 protected Runtime(int pageSize, int totalPages, boolean exec) {
138 if(pageSize <= 0) throw new IllegalArgumentException("pageSize <= 0");
139 if(totalPages <= 0) throw new IllegalArgumentException("totalPages <= 0");
140 if((pageSize&(pageSize-1)) != 0) throw new IllegalArgumentException("pageSize not a power of two");
143 while(pageSize>>>_pageShift != 1) _pageShift++;
144 pageShift = _pageShift;
146 int heapStart = heapStart();
147 int totalMemory = totalPages * pageSize;
148 int stackSize = max(totalMemory/512,ARG_MAX+65536);
151 stackSize = max(stackSize,pageSize);
152 stackSize = (stackSize + pageSize - 1) & ~(pageSize-1);
153 stackPages = stackSize >>> pageShift;
154 heapStart = (heapStart + pageSize - 1) & ~(pageSize-1);
155 if(stackPages + STACK_GUARD_PAGES + (heapStart >>> pageShift) >= totalPages)
156 throw new IllegalArgumentException("total pages too small");
158 if(pageSize < heapStart + stackSize) throw new IllegalArgumentException("total memory too small");
159 heapStart = (heapStart + 4095) & ~4096;
162 stackBottom = totalMemory - stackSize;
165 readPages = new int[totalPages][];
166 writePages = new int[totalPages][];
168 if(totalPages == 1) {
169 readPages[0] = writePages[0] = new int[pageSize>>2];
171 for(int i=(stackBottom >>> pageShift);i<writePages.length;i++) {
172 readPages[i] = writePages[i] = new int[pageSize>>2];
177 fds = new FD[OPEN_MAX];
178 closeOnExec = new boolean[OPEN_MAX];
180 InputStream stdin = win32Hacks ? new Win32ConsoleIS(System.in) : System.in;
181 addFD(new TerminalFD(stdin));
182 addFD(new TerminalFD(System.out));
183 addFD(new TerminalFD(System.err));
187 /** Copy everything from <i>src</i> to <i>addr</i> initializing uninitialized pages if required.
188 Newly initalized pages will be marked read-only if <i>ro</i> is set */
189 protected final void initPages(int[] src, int addr, boolean ro) {
190 int pageWords = (1<<pageShift)>>>2;
191 int pageMask = (1<<pageShift) - 1;
193 for(int i=0;i<src.length;) {
194 int page = addr >>> pageShift;
195 int start = (addr&pageMask)>>2;
196 int elements = min(pageWords-start,src.length-i);
197 if(readPages[page]==null) {
200 if(writePages[page] == null) writePages[page] = readPages[page];
202 System.arraycopy(src,i,readPages[page],start,elements);
208 /** Initialize <i>words</i> of pages starting at <i>addr</i> to 0 */
209 protected final void clearPages(int addr, int words) {
210 int pageWords = (1<<pageShift)>>>2;
211 int pageMask = (1<<pageShift) - 1;
213 for(int i=0;i<words;) {
214 int page = addr >>> pageShift;
215 int start = (addr&pageMask)>>2;
216 int elements = min(pageWords-start,words-i);
217 if(readPages[page]==null) {
218 readPages[page] = writePages[page] = new int[pageWords];
220 if(writePages[page] == null) writePages[page] = readPages[page];
221 for(int j=start;j<start+elements;j++) writePages[page][j] = 0;
228 /** Copies <i>length</i> bytes from the processes memory space starting at
229 <i>addr</i> INTO a java byte array <i>a</i> */
230 public final void copyin(int addr, byte[] buf, int count) throws ReadFaultException {
231 int pageWords = (1<<pageShift)>>>2;
232 int pageMask = pageWords - 1;
235 if(count == 0) return;
237 int word = memRead(addr&~3);
239 case 1: buf[x++] = (byte)((word>>>16)&0xff); if(--count==0) break;
240 case 2: buf[x++] = (byte)((word>>> 8)&0xff); if(--count==0) break;
241 case 3: buf[x++] = (byte)((word>>> 0)&0xff); if(--count==0) break;
245 if((count&~3) != 0) {
249 int[] page = readPages[a >>> (pageShift-2)];
250 if(page == null) throw new ReadFaultException(a<<2);
251 int index = a&pageMask;
252 int n = min(c,pageWords-index);
253 for(int i=0;i<n;i++,x+=4) {
254 int word = page[index+i];
255 buf[x+0] = (byte)((word>>>24)&0xff); buf[x+1] = (byte)((word>>>16)&0xff);
256 buf[x+2] = (byte)((word>>> 8)&0xff); buf[x+3] = (byte)((word>>> 0)&0xff);
260 addr = a<<2; count &=3;
263 int word = memRead(addr);
265 case 3: buf[x+2] = (byte)((word>>>8)&0xff);
266 case 2: buf[x+1] = (byte)((word>>>16)&0xff);
267 case 1: buf[x+0] = (byte)((word>>>24)&0xff);
272 /** Copies <i>length</i> bytes OUT OF the java array <i>a</i> into the processes memory
273 space at <i>addr</i> */
274 public final void copyout(byte[] buf, int addr, int count) throws FaultException {
275 int pageWords = (1<<pageShift)>>>2;
276 int pageWordMask = pageWords - 1;
279 if(count == 0) return;
281 int word = memRead(addr&~3);
283 case 1: word = (word&0xff00ffff)|((buf[x++]&0xff)<<16); if(--count==0) break;
284 case 2: word = (word&0xffff00ff)|((buf[x++]&0xff)<< 8); if(--count==0) break;
285 case 3: word = (word&0xffffff00)|((buf[x++]&0xff)<< 0); if(--count==0) break;
287 memWrite(addr&~3,word);
291 if((count&~3) != 0) {
295 int[] page = writePages[a >>> (pageShift-2)];
296 if(page == null) throw new WriteFaultException(a<<2);
297 int index = a&pageWordMask;
298 int n = min(c,pageWords-index);
299 for(int i=0;i<n;i++,x+=4)
300 page[index+i] = ((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16)|((buf[x+2]&0xff)<<8)|((buf[x+3]&0xff)<<0);
303 addr = a<<2; count&=3;
307 int word = memRead(addr);
309 case 1: word = (word&0x00ffffff)|((buf[x+0]&0xff)<<24); break;
310 case 2: word = (word&0x0000ffff)|((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16); break;
311 case 3: word = (word&0x000000ff)|((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16)|((buf[x+2]&0xff)<<8); break;
317 public final void memcpy(int dst, int src, int count) throws FaultException {
318 int pageWords = (1<<pageShift)>>>2;
319 int pageWordMask = pageWords - 1;
320 if((dst&3) == 0 && (src&3)==0) {
321 if((count&~3) != 0) {
326 int[] srcPage = readPages[s>>>(pageShift-2)];
327 if(srcPage == null) throw new ReadFaultException(s<<2);
328 int[] dstPage = writePages[d>>>(pageShift-2)];
329 if(dstPage == null) throw new WriteFaultException(d<<2);
330 int srcIndex = s&pageWordMask;
331 int dstIndex = d&pageWordMask;
332 int n = min(c,pageWords-max(srcIndex,dstIndex));
333 System.arraycopy(srcPage,srcIndex,dstPage,dstIndex,n);
334 s += n; d += n; c -= n;
336 src = s<<2; dst = d<<2; count&=3;
339 int word1 = memRead(src);
340 int word2 = memRead(dst);
342 case 1: memWrite(dst,(word1&0xff000000)|(word2&0x00ffffff)); break;
343 case 2: memWrite(dst,(word1&0xffff0000)|(word2&0x0000ffff)); break;
344 case 3: memWrite(dst,(word1&0xffffff00)|(word2&0x000000ff)); break;
349 int n = min(count,MAX_CHUNK);
350 byte[] buf = byteBuf(n);
353 count -= n; src += n; dst += n;
358 public final void memset(int addr, int ch, int count) throws FaultException {
359 int pageWords = (1<<pageShift)>>>2;
360 int pageWordMask = pageWords - 1;
362 int fourBytes = ((ch&0xff)<<24)|((ch&0xff)<<16)|((ch&0xff)<<8)|((ch&0xff)<<0);
364 int word = memRead(addr&~3);
366 case 1: word = (word&0xff00ffff)|((ch&0xff)<<16); if(--count==0) break;
367 case 2: word = (word&0xffff00ff)|((ch&0xff)<< 8); if(--count==0) break;
368 case 3: word = (word&0xffffff00)|((ch&0xff)<< 0); if(--count==0) break;
370 memWrite(addr&~3,word);
373 if((count&~3) != 0) {
377 int[] page = readPages[a>>>(pageShift-2)];
378 if(page == null) throw new WriteFaultException(a<<2);
379 int index = a&pageWordMask;
380 int n = min(c,pageWords-index);
381 /* Arrays.fill(page,index,index+n,fourBytes);*/
382 for(int i=index;i<index+n;i++) page[i] = fourBytes;
385 addr = a<<2; count&=3;
388 int word = memRead(addr);
390 case 1: word = (word&0x00ffffff)|(fourBytes&0xff000000); break;
391 case 2: word = (word&0x0000ffff)|(fourBytes&0xffff0000); break;
392 case 3: word = (word&0x000000ff)|(fourBytes&0xffffff00); break;
398 /** Read a word from the processes memory at <i>addr</i> */
399 public final int memRead(int addr) throws ReadFaultException {
400 if((addr & 3) != 0) throw new ReadFaultException(addr);
401 return unsafeMemRead(addr);
404 protected final int unsafeMemRead(int addr) throws ReadFaultException {
405 int page = addr >>> pageShift;
406 int entry = (addr&(1<<pageShift) - 1)>>2;
408 return readPages[page][entry];
409 } catch(ArrayIndexOutOfBoundsException e) {
410 if(page < 0 || page >= readPages.length) throw new ReadFaultException(addr);
411 throw e; // should never happen
412 } catch(NullPointerException e) {
413 throw new ReadFaultException(addr);
417 /** Writes a word to the processes memory at <i>addr</i> */
418 public final void memWrite(int addr, int value) throws WriteFaultException {
419 if((addr & 3) != 0) throw new WriteFaultException(addr);
420 unsafeMemWrite(addr,value);
423 protected final void unsafeMemWrite(int addr, int value) throws WriteFaultException {
424 int page = addr >>> pageShift;
425 int entry = (addr&(1<<pageShift) - 1)>>2;
427 writePages[page][entry] = value;
428 } catch(ArrayIndexOutOfBoundsException e) {
429 if(page < 0 || page >= writePages.length) throw new WriteFaultException(addr);
430 throw e; // should never happen
431 } catch(NullPointerException e) {
432 throw new WriteFaultException(addr);
436 /** Created a new non-empty writable page at page number <i>page</i> */
437 private final int[] initPage(int page) { return initPage(page,false); }
438 /** Created a new non-empty page at page number <i>page</i>. If <i>ro</i> is set the page will be read-only */
439 private final int[] initPage(int page, boolean ro) {
440 int[] buf = new int[(1<<pageShift)>>>2];
441 writePages[page] = ro ? null : buf;
442 readPages[page] = buf;
446 /** Returns the exit status of the process. (only valid if state == DONE)
447 @see Runtime#state */
448 public final int exitStatus() {
449 if(state != EXITED) throw new IllegalStateException("exitStatus() called in an inappropriate state");
453 private int addStringArray(String[] strings, int topAddr) throws FaultException {
454 int count = strings.length;
455 int total = 0; /* null last table entry */
456 for(int i=0;i<count;i++) total += strings[i].length() + 1;
457 total += (count+1)*4;
458 int start = (topAddr - total)&~3;
459 int addr = start + (count+1)*4;
460 int[] table = new int[count+1];
462 for(int i=0;i<count;i++) {
463 byte[] a = getBytes(strings[i]);
465 copyout(a,addr,a.length);
466 memset(addr+a.length,0,1);
467 addr += a.length + 1;
470 for(int i=0;i<count+1;i++) {
471 memWrite(addr,table[i]);
474 } catch(FaultException e) {
475 throw new RuntimeException(e.toString());
480 String[] createEnv(String[] extra) { if(extra == null) extra = new String[0]; return extra; }
482 /** Sets word number <i>index</i> in the _user_info table to <i>word</i>
483 * The user_info table is a chunk of memory in the program's memory defined by the
484 * symbol "user_info". The compiler/interpreter automatically determine the size
485 * and location of the user_info table from the ELF symbol table. setUserInfo and
486 * getUserInfo are used to modify the words in the user_info table. */
487 public void setUserInfo(int index, int word) {
488 if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
490 memWrite(userInfoBase()+index*4,word);
491 } catch(FaultException e) { throw new RuntimeException(e.toString()); }
494 /** Returns the word in the _user_info table entry <i>index</i>
495 @see Runtime#setUserInfo(int,int) setUserInfo */
496 public int getUserInfo(int index) {
497 if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
499 return memRead(userInfoBase()+index*4);
500 } catch(FaultException e) { throw new RuntimeException(e.toString()); }
503 /** Calls _execute() (subclass's execute()) and catches exceptions */
504 private void __execute() {
507 } catch(FaultException e) {
508 if(STDERR_DIAG) e.printStackTrace();
509 exit(128+11,true); // SIGSEGV
511 } catch(ExecutionException e) {
512 if(STDERR_DIAG) e.printStackTrace();
513 exit(128+4,true); // SIGILL
518 /** Executes the process until the PAUSE syscall is invoked or the process exits. Returns true if the process exited. */
519 public final boolean execute() {
520 if(state != PAUSED) throw new IllegalStateException("execute() called in inappropriate state");
521 if(startTime == 0) startTime = System.currentTimeMillis();
524 if(state != PAUSED && state != EXITED && state != EXECED)
525 throw new IllegalStateException("execute() ended up in an inappropriate state (" + state + ")");
526 return state != PAUSED;
529 static String[] concatArgv(String argv0, String[] rest) {
530 String[] argv = new String[rest.length+1];
531 System.arraycopy(rest,0,argv,1,rest.length);
536 public final int run() { return run(null); }
537 public final int run(String argv0, String[] rest) { return run(concatArgv(argv0,rest)); }
538 public final int run(String[] args) { return run(args,null); }
540 /** Runs the process until it exits and returns the exit status.
541 If the process executes the PAUSE syscall execution will be paused for 500ms and a warning will be displayed */
542 public final int run(String[] args, String[] env) {
546 if(STDERR_DIAG) System.err.println("WARNING: Pause requested while executing run()");
548 if(state == EXECED && STDERR_DIAG) System.err.println("WARNING: Process exec()ed while being run under run()");
549 return state == EXITED ? exitStatus() : 0;
552 public final void start() { start(null); }
553 public final void start(String[] args) { start(args,null); }
555 /** Initializes the process and prepairs it to be executed with execute() */
556 public final void start(String[] args, String[] environ) {
557 int top, sp, argsAddr, envAddr;
558 if(state != STOPPED) throw new IllegalStateException("start() called in inappropriate state");
560 if(args == null) args = new String[]{getClass().getName()};
562 sp = top = writePages.length*(1<<pageShift);
564 sp = argsAddr = addStringArray(args,sp);
565 sp = envAddr = addStringArray(createEnv(environ),sp);
566 } catch(FaultException e) {
567 throw new IllegalArgumentException("args/environ too big");
570 if(top - sp > ARG_MAX) throw new IllegalArgumentException("args/environ too big");
572 // HACK: heapStart() isn't always available when the constructor
573 // is run and this sometimes doesn't get initialized
575 heapEnd = heapStart();
576 if(heapEnd == 0) throw new Error("heapEnd == 0");
577 int pageSize = writePages.length == 1 ? 4096 : (1<<pageShift);
578 heapEnd = (heapEnd + pageSize - 1) & ~(pageSize-1);
581 CPUState cpuState = new CPUState();
582 cpuState.r[A0] = argsAddr;
583 cpuState.r[A1] = envAddr;
585 cpuState.r[RA] = 0xdeadbeef;
586 cpuState.r[GP] = gp();
587 cpuState.pc = entryPoint();
588 setCPUState(cpuState);
595 /** Hook for subclasses to do their own startup */
598 public final int call(String sym, Object[] args) throws CallException, FaultException {
599 if(state != PAUSED && state != CALLJAVA) throw new IllegalStateException("call() called in inappropriate state");
600 if(args.length > 7) throw new IllegalArgumentException("args.length > 7");
601 CPUState state = new CPUState();
604 int sp = state.r[SP];
605 int[] ia = new int[args.length];
606 for(int i=0;i<args.length;i++) {
609 if(o instanceof String) {
610 buf = getBytes((String)o);
611 } else if(o instanceof byte[]) {
613 } else if(o instanceof Number) {
614 ia[i] = ((Number)o).intValue();
618 copyout(buf,sp,buf.length);
622 int oldSP = state.r[SP];
623 if(oldSP == sp) return call(sym,ia);
627 int ret = call(sym,ia);
633 public final int call(String sym) throws CallException { return call(sym,new int[]{}); }
634 public final int call(String sym, int a0) throws CallException { return call(sym,new int[]{a0}); }
635 public final int call(String sym, int a0, int a1) throws CallException { return call(sym,new int[]{a0,a1}); }
637 /** Calls a function in the process with the given arguments */
638 public final int call(String sym, int[] args) throws CallException {
639 int func = lookupSymbol(sym);
640 if(func == -1) throw new CallException(sym + " not found");
641 int helper = lookupSymbol("_call_helper");
642 if(helper == -1) throw new CallException("_call_helper not found");
643 return call(helper,func,args);
646 /** Executes the code at <i>addr</i> in the process setting A0-A3 and S0-S3 to the given arguments
647 and returns the contents of V1 when the the pause syscall is invoked */
648 //public final int call(int addr, int a0, int a1, int a2, int a3, int s0, int s1, int s2, int s3) {
649 public final int call(int addr, int a0, int[] rest) throws CallException {
650 if(rest.length > 7) throw new IllegalArgumentException("rest.length > 7");
651 if(state != PAUSED && state != CALLJAVA) throw new IllegalStateException("call() called in inappropriate state");
652 int oldState = state;
653 CPUState saved = new CPUState();
655 CPUState cpustate = saved.dup();
657 cpustate.r[SP] = cpustate.r[SP]&~15;
658 cpustate.r[RA] = 0xdeadbeef;
660 switch(rest.length) {
661 case 7: cpustate.r[S3] = rest[6];
662 case 6: cpustate.r[S2] = rest[5];
663 case 5: cpustate.r[S1] = rest[4];
664 case 4: cpustate.r[S0] = rest[3];
665 case 3: cpustate.r[A3] = rest[2];
666 case 2: cpustate.r[A2] = rest[1];
667 case 1: cpustate.r[A1] = rest[0];
673 setCPUState(cpustate);
675 getCPUState(cpustate);
678 if(state != PAUSED) throw new CallException("Process exit()ed while servicing a call() request");
681 return cpustate.r[V1];
684 /** Allocated an entry in the FileDescriptor table for <i>fd</i> and returns the number.
685 Returns -1 if the table is full. This can be used by subclasses to use custom file
687 public final int addFD(FD fd) {
688 if(state == EXITED || state == EXECED) throw new IllegalStateException("addFD called in inappropriate state");
690 for(i=0;i<OPEN_MAX;i++) if(fds[i] == null) break;
691 if(i==OPEN_MAX) return -1;
693 closeOnExec[i] = false;
697 /** Closes file descriptor <i>fdn</i> and removes it from the file descriptor table */
698 public final boolean closeFD(int fdn) {
699 if(state == EXITED || state == EXECED) throw new IllegalStateException("closeFD called in inappropriate state");
700 if(fdn < 0 || fdn >= OPEN_MAX) return false;
701 if(fds[fdn] == null) return false;
707 /** Duplicates the file descriptor <i>fdn</i> and returns the new fs */
708 public final int dupFD(int fdn) {
710 if(fdn < 0 || fdn >= OPEN_MAX) return -1;
711 if(fds[fdn] == null) return -1;
712 for(i=0;i<OPEN_MAX;i++) if(fds[i] == null) break;
713 if(i==OPEN_MAX) return -1;
714 fds[i] = fds[fdn].dup();
718 public static final int RD_ONLY = 0;
719 public static final int WR_ONLY = 1;
720 public static final int RDWR = 2;
722 public static final int O_CREAT = 0x0200;
723 public static final int O_EXCL = 0x0800;
724 public static final int O_APPEND = 0x0008;
725 public static final int O_TRUNC = 0x0400;
726 public static final int O_NONBLOCK = 0x4000;
727 public static final int O_NOCTTY = 0x8000;
730 FD hostFSOpen(final File f, int flags, int mode, final Object data) throws ErrnoException {
731 if((flags & ~(3|O_CREAT|O_EXCL|O_APPEND|O_TRUNC)) != 0) {
733 System.err.println("WARNING: Unsupported flags passed to open(\"" + f + "\"): " + toHex(flags & ~(3|O_CREAT|O_EXCL|O_APPEND|O_TRUNC)));
734 throw new ErrnoException(ENOTSUP);
736 boolean write = (flags&3) != RD_ONLY;
738 if(sm != null && !(write ? sm.allowWrite(f) : sm.allowRead(f))) throw new ErrnoException(EACCES);
740 if((flags & (O_EXCL|O_CREAT)) == (O_EXCL|O_CREAT)) {
742 if(!Platform.atomicCreateFile(f)) throw new ErrnoException(EEXIST);
743 } catch(IOException e) {
744 throw new ErrnoException(EIO);
746 } else if(!f.exists()) {
747 if((flags&O_CREAT)==0) return null;
748 } else if(f.isDirectory()) {
749 return hostFSDirFD(f,data);
752 final Seekable.File sf;
754 sf = new Seekable.File(f,write,(flags & O_TRUNC) != 0);
755 } catch(FileNotFoundException e) {
756 if(e.getMessage() != null && e.getMessage().indexOf("Permission denied") >= 0) throw new ErrnoException(EACCES);
758 } catch(IOException e) { throw new ErrnoException(EIO); }
760 return new SeekableFD(sf,flags) { protected FStat _fstat() { return hostFStat(f,data); } };
763 FStat hostFStat(File f, Object data) { return new HostFStat(f); }
765 FD hostFSDirFD(File f, Object data) { return null; }
767 FD _open(String path, int flags, int mode) throws ErrnoException {
768 return hostFSOpen(new File(path),flags,mode,null);
771 /** The open syscall */
772 private int sys_open(int addr, int flags, int mode) throws ErrnoException, FaultException {
773 String name = cstring(addr);
775 // HACK: TeX, or GPC, or something really sucks
776 if(name.length() == 1024 && getClass().getName().equals("tests.TeX")) name = name.trim();
778 flags &= ~O_NOCTTY; // this is meaningless under nestedvm
779 FD fd = _open(name,flags,mode);
780 if(fd == null) return -ENOENT;
782 if(fdn == -1) { fd.close(); return -ENFILE; }
786 /** The write syscall */
788 private int sys_write(int fdn, int addr, int count) throws FaultException, ErrnoException {
789 count = Math.min(count,MAX_CHUNK);
790 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
791 if(fds[fdn] == null) return -EBADFD;
792 byte[] buf = byteBuf(count);
793 copyin(addr,buf,count);
795 return fds[fdn].write(buf,0,count);
796 } catch(ErrnoException e) {
797 if(e.errno == EPIPE) sys_exit(128+13);
802 /** The read syscall */
803 private int sys_read(int fdn, int addr, int count) throws FaultException, ErrnoException {
804 count = Math.min(count,MAX_CHUNK);
805 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
806 if(fds[fdn] == null) return -EBADFD;
807 byte[] buf = byteBuf(count);
808 int n = fds[fdn].read(buf,0,count);
813 /** The close syscall */
814 private int sys_close(int fdn) {
815 return closeFD(fdn) ? 0 : -EBADFD;
819 /** The seek syscall */
820 private int sys_lseek(int fdn, int offset, int whence) throws ErrnoException {
821 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
822 if(fds[fdn] == null) return -EBADFD;
823 if(whence != SEEK_SET && whence != SEEK_CUR && whence != SEEK_END) return -EINVAL;
824 int n = fds[fdn].seek(offset,whence);
825 return n < 0 ? -ESPIPE : n;
828 /** The stat/fstat syscall helper */
829 int stat(FStat fs, int addr) throws FaultException {
830 memWrite(addr+0,(fs.dev()<<16)|(fs.inode()&0xffff)); // st_dev (top 16), // st_ino (bottom 16)
831 memWrite(addr+4,((fs.type()&0xf000))|(fs.mode()&0xfff)); // st_mode
832 memWrite(addr+8,fs.nlink()<<16|fs.uid()&0xffff); // st_nlink (top 16) // st_uid (bottom 16)
833 memWrite(addr+12,fs.gid()<<16|0); // st_gid (top 16) // st_rdev (bottom 16)
834 memWrite(addr+16,fs.size()); // st_size
835 memWrite(addr+20,fs.atime()); // st_atime
836 // memWrite(addr+24,0) // st_spare1
837 memWrite(addr+28,fs.mtime()); // st_mtime
838 // memWrite(addr+32,0) // st_spare2
839 memWrite(addr+36,fs.ctime()); // st_ctime
840 // memWrite(addr+40,0) // st_spare3
841 memWrite(addr+44,fs.blksize()); // st_bklsize;
842 memWrite(addr+48,fs.blocks()); // st_blocks
843 // memWrite(addr+52,0) // st_spare4[0]
844 // memWrite(addr+56,0) // st_spare4[1]
848 /** The fstat syscall */
849 private int sys_fstat(int fdn, int addr) throws FaultException {
850 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
851 if(fds[fdn] == null) return -EBADFD;
852 return stat(fds[fdn].fstat(),addr);
861 private int sys_gettimeofday(int timevalAddr, int timezoneAddr) throws FaultException {
862 long now = System.currentTimeMillis();
863 int tv_sec = (int)(now / 1000);
864 int tv_usec = (int)((now%1000)*1000);
865 memWrite(timevalAddr+0,tv_sec);
866 memWrite(timevalAddr+4,tv_usec);
870 private int sys_sleep(int sec) {
871 if(sec < 0) sec = Integer.MAX_VALUE;
873 Thread.sleep((long)sec*1000);
875 } catch(InterruptedException e) {
881 #define _CLOCKS_PER_SEC_ 1000
882 #define _CLOCK_T_ unsigned long
890 private int sys_times(int tms) {
891 long now = System.currentTimeMillis();
892 int userTime = (int)((now - startTime)/16);
893 int sysTime = (int)((now - startTime)/16);
897 memWrite(tms+0,userTime);
898 memWrite(tms+4,sysTime);
899 memWrite(tms+8,userTime);
900 memWrite(tms+12,sysTime);
902 } catch(FaultException e) {
908 private int sys_sysconf(int n) {
910 case _SC_CLK_TCK: return 1000;
911 case _SC_PAGESIZE: return writePages.length == 1 ? 4096 : (1<<pageShift);
912 case _SC_PHYS_PAGES: return writePages.length == 1 ? (1<<pageShift)/4096 : writePages.length;
914 if(STDERR_DIAG) System.err.println("WARNING: Attempted to use unknown sysconf key: " + n);
919 /** The sbrk syscall. This can also be used by subclasses to allocate memory.
920 <i>incr</i> is how much to increase the break by */
921 public final int sbrk(int incr) {
922 if(incr < 0) return -ENOMEM;
923 if(incr==0) return heapEnd;
925 int oldEnd = heapEnd;
926 int newEnd = oldEnd + incr;
927 if(newEnd >= stackBottom) return -ENOMEM;
929 if(writePages.length > 1) {
930 int pageMask = (1<<pageShift) - 1;
931 int pageWords = (1<<pageShift) >>> 2;
932 int start = (oldEnd + pageMask) >>> pageShift;
933 int end = (newEnd + pageMask) >>> pageShift;
935 for(int i=start;i<end;i++) readPages[i] = writePages[i] = new int[pageWords];
936 } catch(OutOfMemoryError e) {
937 if(STDERR_DIAG) System.err.println("WARNING: Caught OOM Exception in sbrk: " + e);
945 /** The getpid syscall */
946 private int sys_getpid() { return getPid(); }
947 int getPid() { return 1; }
949 public static interface CallJavaCB { public int call(int a, int b, int c, int d); }
951 private int sys_calljava(int a, int b, int c, int d) {
952 if(state != RUNNING) throw new IllegalStateException("wound up calling sys_calljava while not in RUNNING");
953 if(callJavaCB != null) {
957 ret = callJavaCB.call(a,b,c,d);
958 } catch(RuntimeException e) {
959 System.err.println("Error while executing callJavaCB");
966 if(STDERR_DIAG) System.err.println("WARNING: calljava syscall invoked without a calljava callback set");
971 private int sys_pause() {
976 private int sys_getpagesize() { return writePages.length == 1 ? 4096 : (1<<pageShift); }
978 /** Hook for subclasses to do something when the process exits */
981 void exit(int status, boolean fromSignal) {
982 if(fromSignal && fds[2] != null) {
984 byte[] msg = getBytes("Process exited on signal " + (status - 128) + "\n");
985 fds[2].write(msg,0,msg.length);
986 } catch(ErrnoException e) { }
989 for(int i=0;i<fds.length;i++) if(fds[i] != null) closeFD(i);
994 private int sys_exit(int status) {
999 private int sys_fcntl(int fdn, int cmd, int arg) {
1002 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
1003 if(fds[fdn] == null) return -EBADFD;
1008 if(arg < 0 || arg >= OPEN_MAX) return -EINVAL;
1009 for(i=arg;i<OPEN_MAX;i++) if(fds[i]==null) break;
1010 if(i==OPEN_MAX) return -EMFILE;
1016 closeOnExec[fdn] = arg != 0;
1019 return closeOnExec[fdn] ? 1 : 0;
1021 if(STDERR_DIAG) System.err.println("WARNING: Unknown fcntl command: " + cmd);
1026 /** The syscall dispatcher.
1027 The should be called by subclasses when the syscall instruction is invoked.
1028 <i>syscall</i> should be the contents of V0 and <i>a</i>, <i>b</i>, <i>c</i>, and <i>d</i> should be
1029 the contenst of A0, A1, A2, and A3. The call MAY change the state
1030 @see Runtime#state state */
1031 protected final int syscall(int syscall, int a, int b, int c, int d, int e, int f) {
1033 int n = _syscall(syscall,a,b,c,d,e,f);
1034 //if(n<0) throw new ErrnoException(-n);
1036 } catch(ErrnoException ex) {
1037 //System.err.println("While executing syscall: " + syscall + ":");
1038 //if(syscall == SYS_open) try { System.err.println("Failed to open " + cstring(a) + " errno " + ex.errno); } catch(Exception e2) { }
1039 //ex.printStackTrace();
1041 } catch(FaultException ex) {
1043 } catch(RuntimeException ex) {
1044 ex.printStackTrace();
1045 throw new Error("Internal Error in _syscall()");
1049 int _syscall(int syscall, int a, int b, int c, int d, int e, int f) throws ErrnoException, FaultException {
1051 case SYS_null: return 0;
1052 case SYS_exit: return sys_exit(a);
1053 case SYS_pause: return sys_pause();
1054 case SYS_write: return sys_write(a,b,c);
1055 case SYS_fstat: return sys_fstat(a,b);
1056 case SYS_sbrk: return sbrk(a);
1057 case SYS_open: return sys_open(a,b,c);
1058 case SYS_close: return sys_close(a);
1059 case SYS_read: return sys_read(a,b,c);
1060 case SYS_lseek: return sys_lseek(a,b,c);
1061 case SYS_getpid: return sys_getpid();
1062 case SYS_calljava: return sys_calljava(a,b,c,d);
1063 case SYS_gettimeofday: return sys_gettimeofday(a,b);
1064 case SYS_sleep: return sys_sleep(a);
1065 case SYS_times: return sys_times(a);
1066 case SYS_getpagesize: return sys_getpagesize();
1067 case SYS_fcntl: return sys_fcntl(a,b,c);
1068 case SYS_sysconf: return sys_sysconf(a);
1069 case SYS_getuid: return sys_getuid();
1070 case SYS_geteuid: return sys_geteuid();
1071 case SYS_getgid: return sys_getgid();
1072 case SYS_getegid: return sys_getegid();
1074 case SYS_memcpy: memcpy(a,b,c); return a;
1075 case SYS_memset: memset(a,b,c); return a;
1086 if(STDERR_DIAG) System.err.println("Attempted to use a UnixRuntime syscall in Runtime (" + syscall + ")");
1089 if(STDERR_DIAG) System.err.println("Attempted to use unknown syscall: " + syscall);
1094 private int sys_getuid() { return 0; }
1095 private int sys_geteuid() { return 0; }
1096 private int sys_getgid() { return 0; }
1097 private int sys_getegid() { return 0; }
1099 public int xmalloc(int size) { int p=malloc(size); if(p==0) throw new RuntimeException("malloc() failed"); return p; }
1100 public int xrealloc(int addr,int newsize) { int p=realloc(addr,newsize); if(p==0) throw new RuntimeException("realloc() failed"); return p; }
1101 public int realloc(int addr, int newsize) { try { return call("realloc",addr,newsize); } catch(CallException e) { return 0; } }
1102 public int malloc(int size) { try { return call("malloc",size); } catch(CallException e) { return 0; } }
1103 public void free(int p) { try { if(p!=0) call("free",p); } catch(CallException e) { /*noop*/ } }
1105 /** Helper function to create a cstring in main memory */
1106 public int strdup(String s) {
1108 if(s == null) s = "(null)";
1109 byte[] a2 = getBytes(s);
1110 a = new byte[a2.length+1];
1111 System.arraycopy(a2,0,a,0,a2.length);
1112 int addr = malloc(a.length);
1113 if(addr == 0) return 0;
1115 copyout(a,addr,a.length);
1116 } catch(FaultException e) {
1123 /** Helper function to read a cstring from main memory */
1124 public final String cstring(int addr) throws ReadFaultException {
1125 StringBuffer sb = new StringBuffer();
1127 int word = memRead(addr&~3);
1129 case 0: if(((word>>>24)&0xff)==0) return sb.toString(); sb.append((char)((word>>>24)&0xff)); addr++;
1130 case 1: if(((word>>>16)&0xff)==0) return sb.toString(); sb.append((char)((word>>>16)&0xff)); addr++;
1131 case 2: if(((word>>> 8)&0xff)==0) return sb.toString(); sb.append((char)((word>>> 8)&0xff)); addr++;
1132 case 3: if(((word>>> 0)&0xff)==0) return sb.toString(); sb.append((char)((word>>> 0)&0xff)); addr++;
1137 /** File Descriptor class */
1138 public static abstract class FD {
1139 private int refCount = 1;
1141 /** Read some bytes. Should return the number of bytes read, 0 on EOF, or throw an IOException on error */
1142 public int read(byte[] a, int off, int length) throws ErrnoException { throw new ErrnoException(EBADFD); }
1143 /** Write. Should return the number of bytes written or throw an IOException on error */
1144 public int write(byte[] a, int off, int length) throws ErrnoException { throw new ErrnoException(EBADFD); }
1146 /** Seek in the filedescriptor. Whence is SEEK_SET, SEEK_CUR, or SEEK_END. Should return -1 on error or the new position. */
1147 public int seek(int n, int whence) throws ErrnoException { return -1; }
1149 public int getdents(byte[] a, int off, int length) throws ErrnoException { throw new ErrnoException(EBADFD); }
1151 /** Return a Seekable object representing this file descriptor (can be read only)
1152 This is required for exec() */
1153 Seekable seekable() { return null; }
1155 private FStat cachedFStat = null;
1156 public final FStat fstat() {
1157 if(cachedFStat == null) cachedFStat = _fstat();
1161 protected abstract FStat _fstat();
1162 public abstract int flags();
1164 /** Closes the fd */
1165 public final void close() { if(--refCount==0) _close(); }
1166 protected void _close() { /* noop*/ }
1168 FD dup() { refCount++; return this; }
1171 /** FileDescriptor class for normal files */
1172 public abstract static class SeekableFD extends FD {
1173 private final int flags;
1174 private final Seekable data;
1176 SeekableFD(Seekable data, int flags) { this.data = data; this.flags = flags; }
1178 protected abstract FStat _fstat();
1179 public int flags() { return flags; }
1181 Seekable seekable() { return data; }
1183 public int seek(int n, int whence) throws ErrnoException {
1186 case SEEK_SET: break;
1187 case SEEK_CUR: n += data.pos(); break;
1188 case SEEK_END: n += data.length(); break;
1193 } catch(IOException e) {
1194 throw new ErrnoException(ESPIPE);
1198 public int write(byte[] a, int off, int length) throws ErrnoException {
1199 if((flags&3) == RD_ONLY) throw new ErrnoException(EBADFD);
1200 // NOTE: There is race condition here but we can't fix it in pure java
1201 if((flags&O_APPEND) != 0) seek(0,SEEK_END);
1203 return data.write(a,off,length);
1204 } catch(IOException e) {
1205 throw new ErrnoException(EIO);
1209 public int read(byte[] a, int off, int length) throws ErrnoException {
1210 if((flags&3) == WR_ONLY) throw new ErrnoException(EBADFD);
1212 int n = data.read(a,off,length);
1213 return n < 0 ? 0 : n;
1214 } catch(IOException e) {
1215 throw new ErrnoException(EIO);
1219 protected void _close() { try { data.close(); } catch(IOException e) { /*ignore*/ } }
1222 public static class InputOutputStreamFD extends FD {
1223 private final InputStream is;
1224 private final OutputStream os;
1226 public InputOutputStreamFD(InputStream is) { this(is,null); }
1227 public InputOutputStreamFD(OutputStream os) { this(null,os); }
1228 public InputOutputStreamFD(InputStream is, OutputStream os) {
1231 if(is == null && os == null) throw new IllegalArgumentException("at least one stream must be supplied");
1234 public int flags() {
1235 if(is != null && os != null) return O_RDWR;
1236 if(is != null) return O_RDONLY;
1237 if(os != null) return O_WRONLY;
1238 throw new Error("should never happen");
1241 public void _close() {
1242 if(is != null) try { is.close(); } catch(IOException e) { /*ignore*/ }
1243 if(os != null) try { os.close(); } catch(IOException e) { /*ignore*/ }
1246 public int read(byte[] a, int off, int length) throws ErrnoException {
1247 if(is == null) return super.read(a,off,length);
1249 int n = is.read(a,off,length);
1250 return n < 0 ? 0 : n;
1251 } catch(IOException e) {
1252 throw new ErrnoException(EIO);
1256 public int write(byte[] a, int off, int length) throws ErrnoException {
1257 if(os == null) return super.write(a,off,length);
1259 os.write(a,off,length);
1261 } catch(IOException e) {
1262 throw new ErrnoException(EIO);
1266 public FStat _fstat() { return new SocketFStat(); }
1269 static class TerminalFD extends InputOutputStreamFD {
1270 public TerminalFD(InputStream is) { this(is,null); }
1271 public TerminalFD(OutputStream os) { this(null,os); }
1272 public TerminalFD(InputStream is, OutputStream os) { super(is,os); }
1273 public void _close() { /* noop */ }
1274 public FStat _fstat() { return new SocketFStat() { public int type() { return S_IFCHR; } public int mode() { return 0600; } }; }
1277 // This is pretty inefficient but it is only used for reading from the console on win32
1278 static class Win32ConsoleIS extends InputStream {
1279 private int pushedBack = -1;
1280 private final InputStream parent;
1281 public Win32ConsoleIS(InputStream parent) { this.parent = parent; }
1282 public int read() throws IOException {
1283 if(pushedBack != -1) { int c = pushedBack; pushedBack = -1; return c; }
1284 int c = parent.read();
1285 if(c == '\r' && (c = parent.read()) != '\n') { pushedBack = c; return '\r'; }
1288 public int read(byte[] buf, int pos, int len) throws IOException {
1290 if(pushedBack != -1 && len > 0) {
1291 buf[0] = (byte) pushedBack;
1293 pos++; len--; pb = true;
1295 int n = parent.read(buf,pos,len);
1296 if(n == -1) return -1;
1297 for(int i=0;i<n;i++) {
1298 if(buf[pos+i] == '\r') {
1300 int c = parent.read();
1301 if(c == '\n') buf[pos+i] = '\n';
1302 else pushedBack = c;
1303 } else if(buf[pos+i+1] == '\n') {
1304 System.arraycopy(buf,pos+i+1,buf,pos+i,len-i-1);
1309 return n + (pb ? 1 : 0);
1313 public abstract static class FStat {
1314 public static final int S_IFIFO = 0010000;
1315 public static final int S_IFCHR = 0020000;
1316 public static final int S_IFDIR = 0040000;
1317 public static final int S_IFREG = 0100000;
1318 public static final int S_IFSOCK = 0140000;
1320 public int mode() { return 0; }
1321 public int nlink() { return 0; }
1322 public int uid() { return 0; }
1323 public int gid() { return 0; }
1324 public int size() { return 0; }
1325 public int atime() { return 0; }
1326 public int mtime() { return 0; }
1327 public int ctime() { return 0; }
1328 public int blksize() { return 512; }
1329 public int blocks() { return (size()+blksize()-1)/blksize(); }
1331 public abstract int dev();
1332 public abstract int type();
1333 public abstract int inode();
1336 public static class SocketFStat extends FStat {
1337 public int dev() { return -1; }
1338 public int type() { return S_IFSOCK; }
1339 public int inode() { return hashCode() & 0x7fff; }
1342 static class HostFStat extends FStat {
1343 private final File f;
1344 private final boolean executable;
1345 public HostFStat(File f) { this(f,false); }
1346 public HostFStat(File f, boolean executable) {
1348 this.executable = executable;
1350 public int dev() { return 1; }
1351 public int inode() { return f.getAbsolutePath().hashCode() & 0x7fff; }
1352 public int type() { return f.isDirectory() ? S_IFDIR : S_IFREG; }
1353 public int nlink() { return 1; }
1356 boolean canread = f.canRead();
1357 if(canread && (executable || f.isDirectory())) mode |= 0111;
1358 if(canread) mode |= 0444;
1359 if(f.canWrite()) mode |= 0222;
1362 public int size() { return (int) f.length(); }
1363 public int mtime() { return (int)(f.lastModified()/1000); }
1367 public static class ReadFaultException extends FaultException {
1368 public ReadFaultException(int addr) { super(addr); }
1370 public static class WriteFaultException extends FaultException {
1371 public WriteFaultException(int addr) { super(addr); }
1373 public static class FaultException extends ExecutionException {
1374 public final int addr;
1375 public final RuntimeException cause;
1376 public FaultException(int addr) { super("fault at: " + toHex(addr)); this.addr = addr; cause = null; }
1377 public FaultException(RuntimeException e) { super(e.toString()); addr = -1; cause = e; }
1379 public static class ExecutionException extends Exception {
1380 private String message = "(null)";
1381 private String location = "(unknown)";
1382 public ExecutionException() { /* noop */ }
1383 public ExecutionException(String s) { if(s != null) message = s; }
1384 void setLocation(String s) { location = s == null ? "(unknown)" : s; }
1385 public final String getMessage() { return message + " at " + location; }
1387 public static class CallException extends Exception {
1388 public CallException(String s) { super(s); }
1391 protected static class ErrnoException extends Exception {
1393 public ErrnoException(int errno) { super("Errno: " + errno); this.errno = errno; }
1397 protected static class CPUState {
1398 public CPUState() { /* noop */ }
1400 public int[] r = new int[32];
1401 /* Floating point regs */
1402 public int[] f = new int[32];
1407 public CPUState dup() {
1408 CPUState c = new CPUState();
1413 for(int i=0;i<32;i++) {
1421 public static class SecurityManager {
1422 public boolean allowRead(File f) { return true; }
1423 public boolean allowWrite(File f) { return true; }
1424 public boolean allowStat(File f) { return true; }
1425 public boolean allowUnlink(File f) { return true; }
1428 // Null pointer check helper function
1429 protected final void nullPointerCheck(int addr) throws ExecutionException {
1431 throw new ExecutionException("Attempted to dereference a null pointer " + toHex(addr));
1434 // Utility functions
1435 byte[] byteBuf(int size) {
1436 if(_byteBuf==null) _byteBuf = new byte[size];
1437 else if(_byteBuf.length < size)
1438 _byteBuf = new byte[min(max(_byteBuf.length*2,size),MAX_CHUNK)];
1442 /** Decode a packed string */
1443 protected static final int[] decodeData(String s, int words) {
1444 if(s.length() % 8 != 0) throw new IllegalArgumentException("string length must be a multiple of 8");
1445 if((s.length() / 8) * 7 < words*4) throw new IllegalArgumentException("string isn't big enough");
1446 int[] buf = new int[words];
1447 int prev = 0, left=0;
1448 for(int i=0,n=0;n<words;i+=8) {
1450 for(int j=0;j<8;j++) { l <<= 7; l |= s.charAt(i+j) & 0x7f; }
1451 if(left > 0) buf[n++] = prev | (int)(l>>>(56-left));
1452 if(n < words) buf[n++] = (int) (l >>> (24-left));
1453 left = (left + 8) & 0x1f;
1454 prev = (int)(l << left);
1459 static byte[] getBytes(String s) {
1461 return s.getBytes("ISO-8859-1");
1462 } catch(UnsupportedEncodingException e) {
1463 return null; // should never happen
1467 static byte[] getNullTerminatedBytes(String s) {
1468 byte[] buf1 = getBytes(s);
1469 byte[] buf2 = new byte[buf1.length+1];
1470 System.arraycopy(buf1,0,buf2,0,buf1.length);
1474 final static String toHex(int n) { return "0x" + Long.toString(n & 0xffffffffL, 16); }
1475 final static int min(int a, int b) { return a < b ? a : b; }
1476 final static int max(int a, int b) { return a > b ? a : b; }