1 // Copyright 2003 Brian Alliet
2 // Based on org.xwt.imp.MIPS by Adam Megacz
3 // Portions Copyright 2003 Adam Megacz
5 package org.ibex.nestedvm;
7 import org.ibex.nestedvm.util.*;
9 import java.util.Arrays;
11 // FEATURE: Look over the public API, make sure we're exposing a bare minimum
12 // (we might make this an interface in the future)
14 public abstract class Runtime implements UsermodeConstants,Registers,Cloneable {
15 /** Number of bits to shift to get the page number (1<<<pageShift == pageSize) */
16 protected final int pageShift;
17 /** Bottom of region of memory allocated to the stack */
18 protected final int stackBottom;
20 /** Readable main memory pages */
21 protected int[][] readPages;
22 /** Writable main memory pages.
23 If the page is writable writePages[x] == readPages[x]; if not writePages[x] == null. */
24 protected int[][] writePages;
26 /** The address of the end of the heap */
29 /** Number of guard pages to keep between the stack and the heap */
30 private static final int STACK_GUARD_PAGES = 4;
32 /** The last address the executable uses (other than the heap/stack) */
33 protected abstract int heapStart();
35 /** The program's entry point */
36 protected abstract int entryPoint();
38 /** The location of the _user_info block (or 0 is there is none) */
39 protected int userInfoBase() { return 0; }
40 protected int userInfoSize() { return 0; }
42 /** The location of the global pointer */
43 protected abstract int gp();
45 /** When the process started */
46 private long startTime;
48 /** Text/Data loaded in memory */
49 public final static int STOPPED = 0;
50 /** Program is executing instructions */
51 public final static int RUNNING = 1;
52 /** Prgram has been started but is paused */
53 public final static int PAUSED = 2;
54 /** Program is executing a callJava() method */
55 public final static int CALLJAVA = 3;
56 /** Program has exited (it cannot currently be restarted) */
57 public final static int EXITED = 4;
58 /** Program has executed a successful exec(), a new Runtime needs to be run (used by UnixRuntime) */
59 public final static int EXECED = 5;
61 /** The current state */
62 protected int state = STOPPED;
63 /** @see Runtime#state state */
64 public final int getState() { return state; }
66 /** The exit status if the process (only valid if state==DONE)
68 private int exitStatus;
69 public ExecutionException exitException;
71 /** Table containing all open file descriptors. (Entries are null if the fd is not in use */
72 FD[] fds = new FD[OPEN_MAX]; // package-private for UnixRuntime
73 boolean closeOnExec[] = new boolean[OPEN_MAX];
75 /** Pointer to a SecurityManager for this process */
76 protected SecurityManager sm;
77 public void setSecurityManager(SecurityManager sm) { this.sm = sm; }
79 /** Pointer to a callback for the call_java syscall */
80 private CallJavaCB callJavaCB;
81 public void setCallJavaCB(CallJavaCB callJavaCB) { this.callJavaCB = callJavaCB; }
83 /** Temporary buffer for read/write operations */
84 private byte[] _byteBuf;
85 /** Max size of temporary buffer
86 @see Runtime#_byteBuf */
87 private final static int MAX_CHUNK = 16*1024*1024 - 1024;
89 /** Subclasses should actually execute program in this method. They should continue
90 executing until state != RUNNING. Only syscall() can modify state. It is safe
91 to only check the state attribute after a call to syscall() */
92 protected abstract void _execute() throws ExecutionException;
94 /** Subclasses should return the address of the symbol <i>symbol</i> or -1 it it doesn't exits in this method
95 This method is only required if the call() function is used */
96 protected int lookupSymbol(String symbol) { return -1; }
98 /** Subclasses should populate a CPUState object representing the cpu state */
99 protected abstract void getCPUState(CPUState state);
101 /** Subclasses should set the CPUState to the state held in <i>state</i> */
102 protected abstract void setCPUState(CPUState state);
104 protected Object clone() throws CloneNotSupportedException {
105 Runtime r = (Runtime) super.clone();
108 r.fds = new FD[OPEN_MAX];
109 for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) r.fds[i] = fds[i].dup();
110 int totalPages = writePages.length;
111 r.readPages = new int[totalPages][];
112 r.writePages = new int[totalPages][];
113 for(int i=0;i<totalPages;i++) {
114 if(readPages[i] == null) continue;
115 if(writePages[i] == null) r.readPages[i] = readPages[i];
116 else r.readPages[i] = r.writePages[i] = (int[])writePages[i].clone();
121 protected Runtime(int pageSize, int totalPages) {
122 if(pageSize <= 0) throw new IllegalArgumentException("pageSize <= 0");
123 if(totalPages <= 0) throw new IllegalArgumentException("totalPages <= 0");
124 if((pageSize&(pageSize-1)) != 0) throw new IllegalArgumentException("pageSize not a power of two");
127 while(pageSize>>>_pageShift != 1) _pageShift++;
128 pageShift = _pageShift;
130 int heapStart = heapStart();
131 int totalMemory = totalPages * pageSize;
132 int stackSize = max(totalMemory/512,ARG_MAX+65536);
135 stackSize = max(stackSize,pageSize);
136 stackSize = (stackSize + pageSize - 1) & ~(pageSize-1);
137 stackPages = stackSize >>> pageShift;
138 heapStart = (heapStart + pageSize) & ~(pageSize-1);
139 if(stackPages + STACK_GUARD_PAGES + (heapStart >>> pageShift) >= totalPages)
140 throw new IllegalArgumentException("total pages too small");
142 if(pageSize < heapStart + stackSize) throw new IllegalArgumentException("total memory too small");
143 heapStart = (heapStart + 4095) & ~4096;
146 stackBottom = totalMemory - stackSize;
149 readPages = new int[totalPages][];
150 writePages = new int[totalPages][];
152 if(totalPages == 1) {
153 readPages[0] = writePages[0] = new int[pageSize>>2];
155 for(int i=(stackBottom >>> pageShift);i<writePages.length;i++) {
156 readPages[i] = writePages[i] = new int[pageSize>>2];
160 addFD(new StdinFD(System.in));
161 addFD(new StdoutFD(System.out));
162 addFD(new StdoutFD(System.err));
165 /** Copy everything from <i>src</i> to <i>addr</i> initializing uninitialized pages if required.
166 Newly initalized pages will be marked read-only if <i>ro</i> is set */
167 protected final void initPages(int[] src, int addr, boolean ro) {
168 int pageWords = (1<<pageShift)>>>2;
169 int pageMask = (1<<pageShift) - 1;
171 for(int i=0;i<src.length;) {
172 int page = addr >>> pageShift;
173 int start = (addr&pageMask)>>2;
174 int elements = min(pageWords-start,src.length-i);
175 if(readPages[page]==null) {
178 if(writePages[page] == null) writePages[page] = readPages[page];
180 System.arraycopy(src,i,readPages[page],start,elements);
186 /** Initialize <i>words</i> of pages starting at <i>addr</i> to 0 */
187 protected final void clearPages(int addr, int words) {
188 int pageWords = (1<<pageShift)>>>2;
189 int pageMask = (1<<pageShift) - 1;
191 for(int i=0;i<words;) {
192 int page = addr >>> pageShift;
193 int start = (addr&pageMask)>>2;
194 int elements = min(pageWords-start,words-i);
195 if(readPages[page]==null) {
196 readPages[page] = writePages[page] = new int[pageWords];
198 if(writePages[page] == null) writePages[page] = readPages[page];
199 for(int j=start;j<start+elements;j++) writePages[page][j] = 0;
206 /** Copies <i>length</i> bytes from the processes memory space starting at
207 <i>addr</i> INTO a java byte array <i>a</i> */
208 public final void copyin(int addr, byte[] buf, int count) throws ReadFaultException {
209 int pageWords = (1<<pageShift)>>>2;
210 int pageMask = pageWords - 1;
213 if(count == 0) return;
215 int word = memRead(addr&~3);
217 case 1: buf[x++] = (byte)((word>>>16)&0xff); if(--count==0) break;
218 case 2: buf[x++] = (byte)((word>>> 8)&0xff); if(--count==0) break;
219 case 3: buf[x++] = (byte)((word>>> 0)&0xff); if(--count==0) break;
223 if((count&~3) != 0) {
227 int[] page = readPages[a >>> (pageShift-2)];
228 if(page == null) throw new ReadFaultException(a<<2);
229 int index = a&pageMask;
230 int n = min(c,pageWords-index);
231 for(int i=0;i<n;i++,x+=4) {
232 int word = page[index+i];
233 buf[x+0] = (byte)((word>>>24)&0xff); buf[x+1] = (byte)((word>>>16)&0xff);
234 buf[x+2] = (byte)((word>>> 8)&0xff); buf[x+3] = (byte)((word>>> 0)&0xff);
238 addr = a<<2; count &=3;
241 int word = memRead(addr);
243 case 3: buf[x+2] = (byte)((word>>>8)&0xff);
244 case 2: buf[x+1] = (byte)((word>>>16)&0xff);
245 case 1: buf[x+0] = (byte)((word>>>24)&0xff);
250 /** Copies <i>length</i> bytes OUT OF the java array <i>a</i> into the processes memory
251 space at <i>addr</i> */
252 public final void copyout(byte[] buf, int addr, int count) throws FaultException {
253 int pageWords = (1<<pageShift)>>>2;
254 int pageWordMask = pageWords - 1;
257 if(count == 0) return;
259 int word = memRead(addr&~3);
261 case 1: word = (word&0xff00ffff)|((buf[x++]&0xff)<<16); if(--count==0) break;
262 case 2: word = (word&0xffff00ff)|((buf[x++]&0xff)<< 8); if(--count==0) break;
263 case 3: word = (word&0xffffff00)|((buf[x++]&0xff)<< 0); if(--count==0) break;
265 memWrite(addr&~3,word);
269 if((count&~3) != 0) {
273 int[] page = writePages[a >>> (pageShift-2)];
274 if(page == null) throw new WriteFaultException(a<<2);
275 int index = a&pageWordMask;
276 int n = min(c,pageWords-index);
277 for(int i=0;i<n;i++,x+=4)
278 page[index+i] = ((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16)|((buf[x+2]&0xff)<<8)|((buf[x+3]&0xff)<<0);
281 addr = a<<2; count&=3;
285 int word = memRead(addr);
287 case 1: word = (word&0x00ffffff)|((buf[x+0]&0xff)<<24); break;
288 case 2: word = (word&0x0000ffff)|((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16); break;
289 case 3: word = (word&0x000000ff)|((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16)|((buf[x+2]&0xff)<<8); break;
295 public final void memcpy(int dst, int src, int count) throws FaultException {
296 int pageWords = (1<<pageShift)>>>2;
297 int pageWordMask = pageWords - 1;
299 if((dst&3) == 0 && (src&3)==0) {
300 if((count&~3) != 0) {
305 int[] srcPage = readPages[s>>>(pageShift-2)];
306 if(srcPage == null) throw new ReadFaultException(s<<2);
307 int[] dstPage = writePages[d>>>(pageShift-2)];
308 if(dstPage == null) throw new WriteFaultException(d<<2);
309 int srcIndex = s&pageWordMask;
310 int dstIndex = d&pageWordMask;
311 int n = min(c,pageWords-max(srcIndex,dstIndex));
312 System.arraycopy(srcPage,srcIndex,dstPage,dstIndex,n);
313 s += n; d += n; c -= n;
315 src = s<<2; dst = d<<2; count&=3;
318 int word1 = memRead(src);
319 int word2 = memRead(dst);
321 case 1: memWrite(dst,(word1&0xff000000)|(word2&0x00ffffff)); break;
322 case 2: memWrite(dst,(word1&0xffff0000)|(word2&0x0000ffff)); break;
323 case 3: memWrite(dst,(word1&0xffffff00)|(word2&0x000000ff)); break;
328 int n = min(count,MAX_CHUNK);
329 byte[] buf = byteBuf(n);
332 count -= n; src += n; dst += n;
337 public final void memset(int addr, int ch, int count) throws FaultException {
338 int pageWords = (1<<pageShift)>>>2;
339 int pageWordMask = pageWords - 1;
341 int fourBytes = ((ch&0xff)<<24)|((ch&0xff)<<16)|((ch&0xff)<<8)|((ch&0xff)<<0);
343 int word = memRead(addr&~3);
345 case 1: word = (word&0xff00ffff)|((ch&0xff)<<16); if(--count==0) break;
346 case 2: word = (word&0xffff00ff)|((ch&0xff)<< 8); if(--count==0) break;
347 case 3: word = (word&0xffffff00)|((ch&0xff)<< 0); if(--count==0) break;
349 memWrite(addr&~3,word);
352 if((count&~3) != 0) {
356 int[] page = readPages[a>>>(pageShift-2)];
357 if(page == null) throw new WriteFaultException(a<<2);
358 int index = a&pageWordMask;
359 int n = min(c,pageWords-index);
360 Arrays.fill(page,index,index+n,fourBytes);
363 addr = a<<2; count&=3;
366 int word = memRead(addr);
368 case 1: word = (word&0x00ffffff)|(fourBytes&0xff000000); break;
369 case 2: word = (word&0x0000ffff)|(fourBytes&0xffff0000); break;
370 case 3: word = (word&0x000000ff)|(fourBytes&0xffffff00); break;
376 /** Read a word from the processes memory at <i>addr</i> */
377 public final int memRead(int addr) throws ReadFaultException {
378 if((addr & 3) != 0) throw new ReadFaultException(addr);
379 return unsafeMemRead(addr);
382 protected final int unsafeMemRead(int addr) throws ReadFaultException {
383 int page = addr >>> pageShift;
384 int entry = (addr&(1<<pageShift) - 1)>>2;
386 return readPages[page][entry];
387 } catch(ArrayIndexOutOfBoundsException e) {
388 if(page < 0 || page >= readPages.length) throw new ReadFaultException(addr);
389 throw e; // should never happen
390 } catch(NullPointerException e) {
391 throw new ReadFaultException(addr);
395 /** Writes a word to the processes memory at <i>addr</i> */
396 public final void memWrite(int addr, int value) throws WriteFaultException {
397 if((addr & 3) != 0) throw new WriteFaultException(addr);
398 unsafeMemWrite(addr,value);
401 protected final void unsafeMemWrite(int addr, int value) throws WriteFaultException {
402 int page = addr >>> pageShift;
403 int entry = (addr&(1<<pageShift) - 1)>>2;
405 writePages[page][entry] = value;
406 } catch(ArrayIndexOutOfBoundsException e) {
407 if(page < 0 || page >= writePages.length) throw new WriteFaultException(addr);
408 throw e; // should never happen
409 } catch(NullPointerException e) {
410 throw new WriteFaultException(addr);
414 /** Created a new non-empty writable page at page number <i>page</i> */
415 private final int[] initPage(int page) { return initPage(page,false); }
416 /** Created a new non-empty page at page number <i>page</i>. If <i>ro</i> is set the page will be read-only */
417 private final int[] initPage(int page, boolean ro) {
418 int[] buf = new int[(1<<pageShift)>>>2];
419 writePages[page] = ro ? null : buf;
420 readPages[page] = buf;
424 /** Returns the exit status of the process. (only valid if state == DONE)
425 @see Runtime#state */
426 public final int exitStatus() {
427 if(state != EXITED) throw new IllegalStateException("exitStatus() called in an inappropriate state");
431 private int addStringArray(String[] strings, int topAddr) throws FaultException {
432 int count = strings.length;
433 int total = 0; /* null last table entry */
434 for(int i=0;i<count;i++) total += strings[i].length() + 1;
435 total += (count+1)*4;
436 int start = (topAddr - total)&~3;
437 int addr = start + (count+1)*4;
438 int[] table = new int[count+1];
440 for(int i=0;i<count;i++) {
441 byte[] a = getBytes(strings[i]);
443 copyout(a,addr,a.length);
444 memset(addr+a.length,0,1);
445 addr += a.length + 1;
448 for(int i=0;i<count+1;i++) {
449 memWrite(addr,table[i]);
452 } catch(FaultException e) {
453 // should never happen
454 throw new Error(e.toString());
459 protected String[] createEnv(String[] extra) { if(extra == null) extra = new String[0]; return extra; }
461 /** Sets word number <i>index</i> in the _user_info table to <i>word</i>
462 * The user_info table is a chunk of memory in the program's memory defined by the
463 * symbol "user_info". The compiler/interpreter automatically determine the size
464 * and location of the user_info table from the ELF symbol table. setUserInfo and
465 * getUserInfo are used to modify the words in the user_info table. */
466 public void setUserInfo(int index, int word) {
467 if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
469 memWrite(userInfoBase()+index*4,word);
470 } catch(FaultException e) { throw new RuntimeException(e.toString()); }
473 /** Returns the word in the _user_info table entry <i>index</i>
474 @see Runtime#setUserInfo(int,int) setUserInfo */
475 public int getUserInfo(int index) {
476 if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
478 return memRead(userInfoBase()+index*4);
479 } catch(FaultException e) { throw new RuntimeException(e.toString()); }
482 /** Calls _execute() (subclass's execute()) and catches exceptions */
483 private void __execute() {
486 } catch(FaultException e) {
488 sys_exit(128+11); // SIGSEGV
490 } catch(ExecutionException e) {
492 System.err.println(e);
493 sys_exit(128+4); // SIGILL
498 /** Executes the process until the PAUSE syscall is invoked or the process exits. Returns true if the process exited. */
499 public final boolean execute() {
500 if(state != PAUSED) throw new IllegalStateException("execute() called in inappropriate state");
501 if(startTime == 0) startTime = System.currentTimeMillis();
504 if(state != PAUSED && state != EXITED && state != EXECED)
505 throw new IllegalStateException("execute() ended up in an inappropriate state (" + state + ")");
506 return state != PAUSED;
509 protected static String[] concatArgv(String argv0, String[] rest) {
510 String[] argv = new String[rest.length+1];
511 System.arraycopy(rest,0,argv,1,rest.length);
516 public final int run() { return run(null); }
517 public final int run(String argv0, String[] rest) { return run(concatArgv(argv0,rest)); }
518 public final int run(String[] args) { return run(args,null); }
520 /** Runs the process until it exits and returns the exit status.
521 If the process executes the PAUSE syscall execution will be paused for 500ms and a warning will be displayed */
522 public final int run(String[] args, String[] env) {
526 System.err.println("WARNING: Pause requested while executing run()");
528 if(state == EXECED) System.err.println("WARNING: Process exec()ed while being run under run()");
529 return state == EXITED ? exitStatus() : 0;
532 public final void start() { start(null); }
533 public final void start(String[] args) { start(args,null); }
535 /** Initializes the process and prepairs it to be executed with execute() */
536 public final void start(String[] args, String[] environ) {
537 int top, sp, argsAddr, envAddr;
538 if(state != STOPPED) throw new IllegalStateException("start() called in inappropriate state");
540 if(args == null) args = new String[]{getClass().getName()};
542 sp = top = writePages.length*(1<<pageShift);
544 sp = argsAddr = addStringArray(args,sp);
545 sp = envAddr = addStringArray(createEnv(environ),sp);
546 } catch(FaultException e) {
547 throw new IllegalArgumentException("args/environ too big");
550 if(top - sp > ARG_MAX) throw new IllegalArgumentException("args/environ too big");
552 CPUState cpuState = new CPUState();
553 cpuState.r[A0] = argsAddr;
554 cpuState.r[A1] = envAddr;
556 cpuState.r[RA] = 0xdeadbeef;
557 cpuState.r[GP] = gp();
558 cpuState.pc = entryPoint();
559 setCPUState(cpuState);
566 /** Hook for subclasses to do their own startup */
567 protected void _started() { }
569 public final int call(String sym, Object[] args) throws CallException, FaultException {
570 if(state != PAUSED && state != CALLJAVA) throw new IllegalStateException("call() called in inappropriate state");
571 if(args.length > 7) throw new IllegalArgumentException("args.length > 7");
572 CPUState state = new CPUState();
575 int sp = state.r[SP];
576 int[] ia = new int[args.length];
577 for(int i=0;i<args.length;i++) {
580 if(o instanceof String) {
581 buf = getBytes((String)o);
582 } else if(o instanceof byte[]) {
584 } else if(o instanceof Number) {
585 ia[i] = ((Number)o).intValue();
589 copyout(buf,sp,buf.length);
593 int oldSP = state.r[SP];
594 if(oldSP == sp) return call(sym,ia);
598 int ret = call(sym,ia);
604 public final int call(String sym) throws CallException { return call(sym,new int[]{}); }
605 public final int call(String sym, int a0) throws CallException { return call(sym,new int[]{a0}); }
606 public final int call(String sym, int a0, int a1) throws CallException { return call(sym,new int[]{a0,a1}); }
608 /** Calls a function in the process with the given arguments */
609 public final int call(String sym, int[] args) throws CallException {
610 int func = lookupSymbol(sym);
611 if(func == -1) throw new CallException(sym + " not found");
612 int helper = lookupSymbol("_call_helper");
613 if(helper == -1) throw new CallException("_call_helper not found");
614 return call(helper,func,args);
617 /** Executes the code at <i>addr</i> in the process setting A0-A3 and S0-S3 to the given arguments
618 and returns the contents of V1 when the the pause syscall is invoked */
619 //public final int call(int addr, int a0, int a1, int a2, int a3, int s0, int s1, int s2, int s3) {
620 public final int call(int addr, int a0, int[] rest) throws CallException {
621 if(rest.length > 7) throw new IllegalArgumentException("rest.length > 7");
622 if(state != PAUSED && state != CALLJAVA) throw new IllegalStateException("call() called in inappropriate state");
623 int oldState = state;
624 CPUState saved = new CPUState();
626 CPUState cpustate = saved.dup();
628 cpustate.r[SP] = cpustate.r[SP]&~15;
629 cpustate.r[RA] = 0xdeadbeef;
631 switch(rest.length) {
632 case 7: cpustate.r[S3] = rest[6];
633 case 6: cpustate.r[S2] = rest[5];
634 case 5: cpustate.r[S1] = rest[4];
635 case 4: cpustate.r[S0] = rest[3];
636 case 3: cpustate.r[A3] = rest[2];
637 case 2: cpustate.r[A2] = rest[1];
638 case 1: cpustate.r[A1] = rest[0];
644 setCPUState(cpustate);
646 getCPUState(cpustate);
649 if(state != PAUSED) throw new CallException("Process exit()ed while servicing a call() request");
652 return cpustate.r[V1];
655 /** Determines if the process can access <i>fileName</i>. The default implementation simply logs
656 the request and allows it */
657 protected boolean allowFileAccess(String fileName, boolean write) {
658 //System.err.println("Allowing " + (write?"write":"read-only") + " access to " + fileName);
662 /** Allocated an entry in the FileDescriptor table for <i>fd</i> and returns the number.
663 Returns -1 if the table is full. This can be used by subclasses to use custom file
665 public int addFD(FD fd) {
666 if(state == EXITED || state == EXECED) throw new IllegalStateException("addFD called in inappropriate state");
668 for(i=0;i<OPEN_MAX;i++) if(fds[i] == null) break;
669 if(i==OPEN_MAX) return -1;
671 closeOnExec[i] = false;
675 /** Closes file descriptor <i>fdn</i> and removes it from the file descriptor table */
676 public boolean closeFD(int fdn) {
677 if(state == EXITED || state == EXECED) throw new IllegalStateException("closeFD called in inappropriate state");
678 if(fdn < 0 || fdn >= OPEN_MAX) return false;
679 if(fds[fdn] == null) return false;
685 /** Duplicates the file descriptor <i>fdn</i> and returns the new fs */
686 public int dupFD(int fdn) {
688 if(fdn < 0 || fdn >= OPEN_MAX) return -1;
689 if(fds[fdn] == null) return -1;
690 for(i=0;i<OPEN_MAX;i++) if(fds[i] == null) break;
691 if(i==OPEN_MAX) return -1;
692 fds[i] = fds[fdn].dup();
696 public static final int RD_ONLY = 0;
697 public static final int WR_ONLY = 1;
698 public static final int RDWR = 2;
700 public static final int O_CREAT = 0x0200;
701 public static final int O_EXCL = 0x0800;
702 public static final int O_APPEND = 0x0008;
703 public static final int O_TRUNC = 0x0400;
704 public static final int O_NONBLOCK = 0x4000;
706 FD hostFSOpen(final File f, int flags, int mode) throws ErrnoException {
707 if((flags & ~(3|O_CREAT|O_EXCL|O_APPEND|O_TRUNC)) != 0) {
708 System.err.println("WARNING: Unsupported flags passed to open(): " + toHex(flags & ~(3|O_CREAT|O_EXCL|O_APPEND|O_TRUNC)));
709 throw new ErrnoException(ENOTSUP);
711 boolean write = mode!=RD_ONLY;
713 if(sm != null && !(write ? sm.allowWrite(f) : sm.allowRead(f))) throw new ErrnoException(EACCES);
715 if((flags & (O_EXCL|O_CREAT)) == (O_EXCL|O_CREAT)) {
717 // NOTE: createNewFile is a Java2 function
718 if(!f.createNewFile()) throw new ErrnoException(EEXIST);
719 } catch(IOException e) {
720 throw new ErrnoException(EIO);
722 } else if(!f.exists()) {
723 if((flags&O_CREAT)==0) return null;
724 } else if(f.isDirectory()) {
725 return hostFSDirFD(f);
728 final Seekable.File sf;
730 sf = new Seekable.File(f,write);
731 } catch(FileNotFoundException e) {
732 if(e.getMessage() != null && e.getMessage().indexOf("Permission denied") >= 0) throw new ErrnoException(EACCES);
734 } catch(IOException e) { throw new ErrnoException(EIO); }
736 return new SeekableFD(sf,flags) { protected FStat _fstat() { return hostFStat(f); } };
739 FStat hostFStat(File f) { return new HostFStat(f); }
740 FD hostFSDirFD(File f) { return null; }
742 FD _open(String path, int flags, int mode) throws ErrnoException {
743 return hostFSOpen(new File(path),flags,mode);
746 /** The open syscall */
747 private int sys_open(int addr, int flags, int mode) throws ErrnoException, FaultException {
748 FD fd = _open(cstring(addr),flags,mode);
749 if(fd == null) return -ENOENT;
751 if(fdn == -1) { fd.close(); return -ENFILE; }
755 /** The write syscall */
756 private int sys_write(int fdn, int addr, int count) throws FaultException {
757 count = Math.min(count,MAX_CHUNK);
758 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
759 if(fds[fdn] == null || !fds[fdn].writable()) return -EBADFD;
761 byte[] buf = byteBuf(count);
762 copyin(addr,buf,count);
763 return fds[fdn].write(buf,0,count);
764 } catch(IOException e) {
765 // NOTE: This should really send a SIGPIPE
766 if(e.getMessage().equals("Pipe closed")) return sys_exit(128+13);
771 /** The read syscall */
772 private int sys_read(int fdn, int addr, int count) throws FaultException {
773 count = Math.min(count,MAX_CHUNK);
774 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
775 if(fds[fdn] == null || !fds[fdn].readable()) return -EBADFD;
777 byte[] buf = byteBuf(count);
778 int n = fds[fdn].read(buf,0,count);
781 } catch(IOException e) {
786 /** The close syscall */
787 private int sys_close(int fdn) {
788 return closeFD(fdn) ? 0 : -EBADFD;
792 /** The seek syscall */
793 private int sys_lseek(int fdn, int offset, int whence) {
794 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
795 if(fds[fdn] == null) return -EBADFD;
796 if(whence != SEEK_SET && whence != SEEK_CUR && whence != SEEK_END) return -EINVAL;
798 int n = fds[fdn].seek(offset,whence);
799 return n < 0 ? -ESPIPE : n;
800 } catch(IOException e) {
805 /** The stat/fstat syscall helper */
806 int stat(FStat fs, int addr) throws FaultException {
807 memWrite(addr+0,(fs.dev()<<16)|(fs.inode()&0xffff)); // st_dev (top 16), // st_ino (bottom 16)
808 memWrite(addr+4,((fs.type()&0xf000))|(fs.mode()&0xfff)); // st_mode
809 memWrite(addr+8,1<<16); // st_nlink (top 16) // st_uid (bottom 16)
810 memWrite(addr+12,0); // st_gid (top 16) // st_rdev (bottom 16)
811 memWrite(addr+16,fs.size()); // st_size
812 memWrite(addr+20,fs.atime()); // st_atime
813 // memWrite(addr+24,0) // st_spare1
814 memWrite(addr+28,fs.mtime()); // st_mtime
815 // memWrite(addr+32,0) // st_spare2
816 memWrite(addr+36,fs.ctime()); // st_ctime
817 // memWrite(addr+40,0) // st_spare3
818 memWrite(addr+44,fs.blksize()); // st_bklsize;
819 memWrite(addr+48,fs.blocks()); // st_blocks
820 // memWrite(addr+52,0) // st_spare4[0]
821 // memWrite(addr+56,0) // st_spare4[1]
825 /** The fstat syscall */
826 private int sys_fstat(int fdn, int addr) throws FaultException {
827 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
828 if(fds[fdn] == null) return -EBADFD;
829 return stat(fds[fdn].fstat(),addr);
838 private int sys_gettimeofday(int timevalAddr, int timezoneAddr) throws FaultException {
839 long now = System.currentTimeMillis();
840 int tv_sec = (int)(now / 1000);
841 int tv_usec = (int)((now%1000)*1000);
842 memWrite(timevalAddr+0,tv_sec);
843 memWrite(timevalAddr+4,tv_usec);
847 private int sys_sleep(int sec) {
848 if(sec < 0) sec = Integer.MAX_VALUE;
850 Thread.sleep((long)sec*1000);
852 } catch(InterruptedException e) {
858 #define _CLOCKS_PER_SEC_ 1000
859 #define _CLOCK_T_ unsigned long
867 private int sys_times(int tms) {
868 long now = System.currentTimeMillis();
869 int userTime = (int)((now - startTime)/16);
870 int sysTime = (int)((now - startTime)/16);
874 memWrite(tms+0,userTime);
875 memWrite(tms+4,sysTime);
876 memWrite(tms+8,userTime);
877 memWrite(tms+12,sysTime);
879 } catch(FaultException e) {
885 private int sys_sysconf(int n) {
887 case _SC_CLK_TCK: return 1000;
889 System.err.println("WARNING: Attempted to use unknown sysconf key: " + n);
894 /** The sbrk syscall. This can also be used by subclasses to allocate memory.
895 <i>incr</i> is how much to increase the break by */
896 public int sbrk(int incr) {
897 if(incr < 0) return -ENOMEM;
898 if(incr==0) return heapEnd;
900 int oldEnd = heapEnd;
901 int newEnd = oldEnd + incr;
902 if(newEnd >= stackBottom) return -ENOMEM;
904 if(writePages.length > 1) {
905 int pageMask = (1<<pageShift) - 1;
906 int pageWords = (1<<pageShift) >>> 2;
907 int start = (oldEnd + pageMask) >>> pageShift;
908 int end = (newEnd + pageMask) >>> pageShift;
910 for(int i=start;i<end;i++) readPages[i] = writePages[i] = new int[pageWords];
911 } catch(OutOfMemoryError e) {
912 System.err.println("WARNING: Caught OOM Exception in sbrk: " + e);
920 /** The getpid syscall */
921 private int sys_getpid() { return getPid(); }
922 protected int getPid() { return 1; }
924 public static interface CallJavaCB { public int call(int a, int b, int c, int d); }
926 private int sys_calljava(int a, int b, int c, int d) {
927 if(state != RUNNING) throw new IllegalStateException("wound up calling sys_calljava while not in RUNNING");
928 if(callJavaCB != null) {
932 ret = callJavaCB.call(a,b,c,d);
933 } catch(RuntimeException e) {
934 System.err.println("Error while executing callJavaCB");
941 System.err.println("WARNING: calljava syscall invoked without a calljava callback set");
946 private int sys_pause() {
951 private int sys_getpagesize() { return writePages.length == 1 ? 4096 : (1<<pageShift); }
953 private int sys_isatty(int fdn) {
954 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
955 if(fds[fdn] == null) return -EBADFD;
956 return fds[fdn].isatty() ? 1 : 0;
960 /** Hook for subclasses to do something when the process exits */
961 protected void _exited() { }
963 private int sys_exit(int status) {
965 for(int i=0;i<fds.length;i++) if(fds[i] != null) closeFD(i);
971 private int sys_fcntl(int fdn, int cmd, int arg) {
974 if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
975 if(fds[fdn] == null) return -EBADFD;
980 if(arg < 0 || arg >= OPEN_MAX) return -EINVAL;
981 for(i=arg;i<OPEN_MAX;i++) if(fds[i]==null) break;
982 if(i==OPEN_MAX) return -EMFILE;
987 if(fd.writable() && fd.readable()) flags = 2;
988 else if(fd.writable()) flags = 1;
991 closeOnExec[fdn] = arg != 0;
994 return closeOnExec[fdn] ? 1 : 0;
996 System.err.println("WARNING: Unknown fcntl command: " + cmd);
1001 /** The syscall dispatcher.
1002 The should be called by subclasses when the syscall instruction is invoked.
1003 <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
1004 the contenst of A0, A1, A2, and A3. The call MAY change the state
1005 @see Runtime#state state */
1006 protected final int syscall(int syscall, int a, int b, int c, int d) {
1008 return _syscall(syscall,a,b,c,d);
1009 } catch(ErrnoException e) {
1010 e.printStackTrace();
1012 } catch(FaultException e) {
1014 } catch(RuntimeException e) {
1015 e.printStackTrace();
1016 throw new Error("Internal Error in _syscall()");
1020 int _syscall(int syscall, int a, int b, int c, int d) throws ErrnoException, FaultException {
1022 case SYS_null: return 0;
1023 case SYS_exit: return sys_exit(a);
1024 case SYS_pause: return sys_pause();
1025 case SYS_write: return sys_write(a,b,c);
1026 case SYS_fstat: return sys_fstat(a,b);
1027 case SYS_sbrk: return sbrk(a);
1028 case SYS_open: return sys_open(a,b,c);
1029 case SYS_close: return sys_close(a);
1030 case SYS_read: return sys_read(a,b,c);
1031 case SYS_lseek: return sys_lseek(a,b,c);
1032 case SYS_getpid: return sys_getpid();
1033 case SYS_calljava: return sys_calljava(a,b,c,d);
1034 case SYS_gettimeofday: return sys_gettimeofday(a,b);
1035 case SYS_sleep: return sys_sleep(a);
1036 case SYS_times: return sys_times(a);
1037 case SYS_getpagesize: return sys_getpagesize();
1038 case SYS_isatty: return sys_isatty(a);
1039 case SYS_fcntl: return sys_fcntl(a,b,c);
1040 case SYS_sysconf: return sys_sysconf(a);
1051 System.err.println("Attempted to use a UnixRuntime syscall in Runtime (" + syscall + ")");
1054 System.err.println("Attempted to use unknown syscall: " + syscall);
1059 public int xmalloc(int size) { int p=malloc(size); if(p==0) throw new RuntimeException("malloc() failed"); return p; }
1060 public int xrealloc(int addr,int newsize) { int p=realloc(addr,newsize); if(p==0) throw new RuntimeException("realloc() failed"); return p; }
1061 public int realloc(int addr, int newsize) { try { return call("realloc",addr,newsize); } catch(CallException e) { return 0; } }
1062 public int malloc(int size) { try { return call("malloc",size); } catch(CallException e) { return 0; } }
1063 public void free(int p) { try { if(p!=0) call("free",p); } catch(CallException e) { /*noop*/ } }
1065 /** Helper function to create a cstring in main memory */
1066 public int strdup(String s) {
1068 if(s == null) s = "(null)";
1069 byte[] a2 = getBytes(s);
1070 a = new byte[a2.length+1];
1071 System.arraycopy(a2,0,a,0,a2.length);
1072 int addr = malloc(a.length);
1073 if(addr == 0) return 0;
1075 copyout(a,addr,a.length);
1076 } catch(FaultException e) {
1083 /** Helper function to read a cstring from main memory */
1084 public String cstring(int addr) throws ReadFaultException {
1085 StringBuffer sb = new StringBuffer();
1087 int word = memRead(addr&~3);
1089 case 0: if(((word>>>24)&0xff)==0) return sb.toString(); sb.append((char)((word>>>24)&0xff)); addr++;
1090 case 1: if(((word>>>16)&0xff)==0) return sb.toString(); sb.append((char)((word>>>16)&0xff)); addr++;
1091 case 2: if(((word>>> 8)&0xff)==0) return sb.toString(); sb.append((char)((word>>> 8)&0xff)); addr++;
1092 case 3: if(((word>>> 0)&0xff)==0) return sb.toString(); sb.append((char)((word>>> 0)&0xff)); addr++;
1097 /** File Descriptor class */
1098 public static abstract class FD {
1099 private int refCount = 1;
1101 /** returns true if the fd is readable */
1102 public boolean readable() { return false; }
1103 /** returns true if the fd is writable */
1104 public boolean writable() { return false; }
1106 /** Read some bytes. Should return the number of bytes read, 0 on EOF, or throw an IOException on error */
1107 public int read(byte[] a, int off, int length) throws IOException { throw new IOException("no definition"); }
1108 /** Write. Should return the number of bytes written or throw an IOException on error */
1109 public int write(byte[] a, int off, int length) throws IOException { throw new IOException("no definition"); }
1111 /** Seek in the filedescriptor. Whence is SEEK_SET, SEEK_CUR, or SEEK_END. Should return -1 on error or the new position. */
1112 public int seek(int n, int whence) throws IOException { return -1; }
1114 /** Return a Seekable object representing this file descriptor (can be read only)
1115 This is required for exec() */
1116 Seekable seekable() { return null; }
1118 /** Should return true if this is a tty */
1119 // FEATURE: get rid of the isatty syscall and just do with newlib's dumb isatty.c
1120 public boolean isatty() { return false; }
1122 private FStat cachedFStat = null;
1123 public final FStat fstat() {
1124 if(cachedFStat == null) cachedFStat = _fstat();
1128 protected abstract FStat _fstat();
1130 /** Closes the fd */
1131 public final void close() { if(--refCount==0) _close(); }
1132 protected void _close() { /* noop*/ }
1134 FD dup() { refCount++; return this; }
1137 /** FileDescriptor class for normal files */
1138 public abstract static class SeekableFD extends FD {
1139 private final int flags;
1140 private final Seekable data;
1141 public boolean readable() { return (flags&3) != WR_ONLY; }
1142 public boolean writable() { return (flags&3) != RD_ONLY; }
1144 SeekableFD(Seekable data, int flags) { this.data = data; this.flags = flags; }
1146 protected abstract FStat _fstat();
1148 Seekable seekable() { return data; }
1150 public int seek(int n, int whence) throws IOException {
1152 case SEEK_SET: break;
1153 case SEEK_CUR: n += data.pos(); break;
1154 case SEEK_END: n += data.length(); break;
1161 public int write(byte[] a, int off, int length) throws IOException {
1162 // NOTE: There is race condition here but we can't fix it in pure java
1163 if((flags&O_APPEND) != 0) seek(0,SEEK_END);
1164 return data.write(a,off,length);
1167 public int read(byte[] a, int off, int length) throws IOException {
1168 int n = data.read(a,off,length);
1169 return n < 0 ? 0 : n;
1172 protected void _close() { try { data.close(); } catch(IOException e) { /*ignore*/ } }
1175 public static class OutputStreamFD extends FD {
1176 private OutputStream os;
1177 public boolean writable() { return true; }
1178 public OutputStreamFD(OutputStream os) { this.os = os; }
1179 public int write(byte[] a, int off, int length) throws IOException { os.write(a,off,length); return length; }
1180 public void _close() { try { os.close(); } catch(IOException e) { /*ignore*/ } }
1181 public FStat _fstat() { return new FStat(); }
1184 public static class InputStreamFD extends FD {
1185 private InputStream is;
1186 public boolean readable() { return true; }
1187 public InputStreamFD(InputStream is) { this.is = is; }
1188 public int read(byte[] a, int off, int length) throws IOException { int n = is.read(a,off,length); return n < 0 ? 0 : n; }
1189 public void _close() { try { is.close(); } catch(IOException e) { /*ignore*/ } }
1190 public FStat _fstat() { return new FStat(); }
1193 protected static class StdinFD extends InputStreamFD {
1194 public StdinFD(InputStream is) { super(is); }
1195 public void _close() { /* noop */ }
1196 public FStat _fstat() { return new FStat() { public int type() { return S_IFCHR; } }; }
1197 public boolean isatty() { return true; }
1199 protected static class StdoutFD extends OutputStreamFD {
1200 public StdoutFD(OutputStream os) { super(os); }
1201 public void _close() { /* noop */ }
1202 public FStat _fstat() { return new FStat() { public int type() { return S_IFCHR; } }; }
1203 public boolean isatty() { return true; }
1206 public static class FStat {
1207 public static final int S_IFIFO = 0010000;
1208 public static final int S_IFCHR = 0020000;
1209 public static final int S_IFDIR = 0040000;
1210 public static final int S_IFREG = 0100000;
1212 public int dev() { return -1; }
1213 // FEATURE: inode numbers are calculated inconsistently throught the runtime
1214 public int inode() { return hashCode() & 0xfffff; }
1215 public int mode() { return 0; }
1216 public int type() { return S_IFIFO; }
1217 public int nlink() { return 0; }
1218 public int uid() { return 0; }
1219 public int gid() { return 0; }
1220 public int size() { return 0; }
1221 public int atime() { return 0; }
1222 public int mtime() { return 0; }
1223 public int ctime() { return 0; }
1224 public int blksize() { return 512; }
1225 public int blocks() { return (size()+blksize()-1)/blksize(); }
1228 protected static class HostFStat extends FStat {
1229 private final File f;
1230 private final boolean executable;
1231 public HostFStat(File f) {
1233 executable = executable();
1235 public int dev() { return 1; }
1236 public int inode() { return f.getName().hashCode() & 0xffff; }
1237 public int type() { return f.isDirectory() ? S_IFDIR : S_IFREG; }
1238 public int nlink() { return 1; }
1241 boolean canread = f.canRead();
1242 if(canread && (executable || f.isDirectory())) mode |= 0111;
1243 if(canread) mode |= 0444;
1244 if(f.canWrite()) mode |= 0222;
1247 public int size() { return (int) f.length(); }
1248 public int mtime() { return (int)(f.lastModified()/1000); }
1250 boolean executable() { return false; }
1254 public class ReadFaultException extends FaultException {
1255 public ReadFaultException(int addr) { super(addr); }
1257 public class WriteFaultException extends FaultException {
1258 public WriteFaultException(int addr) { super(addr); }
1260 public abstract class FaultException extends ExecutionException {
1262 public FaultException(int addr) { super("fault at: " + toHex(addr)); this.addr = addr; }
1264 public static class ExecutionException extends Exception {
1265 private String message = "(null)";
1266 private String location = "(unknown)";
1267 public ExecutionException() { /* noop */ }
1268 public ExecutionException(String s) { if(s != null) message = s; }
1269 void setLocation(String s) { location = s == null ? "(unknown)" : s; }
1270 public final String getMessage() { return message + " at " + location; }
1272 public static class CallException extends Exception {
1273 public CallException(String s) { super(s); }
1276 protected static class ErrnoException extends Exception {
1278 public ErrnoException(int errno) { super("Errno: " + errno); this.errno = errno; }
1282 protected static class CPUState {
1283 public CPUState() { /* noop */ }
1285 public int[] r = new int[32];
1286 /* Floating point regs */
1287 public int[] f = new int[32];
1292 public CPUState dup() {
1293 CPUState c = new CPUState();
1298 for(int i=0;i<32;i++) {
1306 public static class SecurityManager {
1307 public boolean allowRead(File f) { return true; }
1308 public boolean allowWrite(File f) { return true; }
1309 public boolean allowStat(File f) { return true; }
1312 // Null pointer check helper function
1313 protected final void nullPointerCheck(int addr) throws ExecutionException {
1315 throw new ExecutionException("Attempted to dereference a null pointer " + toHex(addr));
1318 // Utility functions
1319 private byte[] byteBuf(int size) {
1320 if(_byteBuf==null) _byteBuf = new byte[size];
1321 else if(_byteBuf.length < size)
1322 _byteBuf = new byte[min(max(_byteBuf.length*2,size),MAX_CHUNK)];
1326 protected static String getSystemProperty(String key) {
1328 return System.getProperty(key);
1329 } catch(SecurityException e) {
1334 /** Decode a packed string */
1335 protected static final int[] decodeData(String s, int words) {
1336 if(s.length() % 8 != 0) throw new IllegalArgumentException("string length must be a multiple of 8");
1337 if((s.length() / 8) * 7 < words*4) throw new IllegalArgumentException("string isn't big enough");
1338 int[] buf = new int[words];
1339 int prev = 0, left=0;
1340 for(int i=0,n=0;n<words;i+=8) {
1342 for(int j=0;j<8;j++) { l <<= 7; l |= s.charAt(i+j) & 0x7f; }
1343 if(left > 0) buf[n++] = prev | (int)(l>>>(56-left));
1344 if(n < words) buf[n++] = (int) (l >>> (24-left));
1345 left = (left + 8) & 0x1f;
1346 prev = (int)(l << left);
1351 protected static byte[] getBytes(String s) {
1353 return s.getBytes("ISO-8859-1");
1354 } catch(UnsupportedEncodingException e) {
1355 return null; // should never happen
1359 protected final static String toHex(int n) { return "0x" + Long.toString(n & 0xffffffffL, 16); }
1360 protected final static int min(int a, int b) { return a < b ? a : b; }
1361 protected final static int max(int a, int b) { return a > b ? a : b; }