// FEATURE: Look over the public API, make sure we're exposing a bare minimum
// (we might make this an interface in the future)
-public abstract class Runtime implements UsermodeConstants,Registers {
- /** Pages are 4k in size */
- protected final int PAGE_SIZE;
- protected final int PAGE_WORDS;
- protected final int PAGE_SHIFT;
- protected final int TOTAL_PAGES;
- /** This is the upper limit of the pages allocated by the sbrk() syscall. */
- protected final int BRK_LIMIT;
- protected final int STACK_BOTTOM;
-
- /** This is the maximum size of command line arguments */
- public final static int ARGS_MAX = 1024*1024;
-
- /** True if we allow empty pages (_emptyPage) to exist in memory.
- Empty pages are pages which are allocated by the program but do not contain any
- data yet (they are all 0s). If empty pages are allowed subclasses must always
- access main memory with the memRead and memWrite functions */
- private final boolean allowEmptyPages;
- /** the "empty page" */
- private final static int[] _emptyPage = new int[0];
-
- protected final static boolean isEmptyPage(int[] page) { return page == _emptyPage; }
-
- /** Returns a new empty page (_emptyPage is empty pages are enabled or a new zero'd page) */
- private final int[] emptyPage() { return allowEmptyPages ? _emptyPage : new int[PAGE_WORDS]; }
+public abstract class Runtime implements UsermodeConstants,Registers,Cloneable {
+ /** Number of bits to shift to get the page number (1<<<pageShift == pageSize) */
+ protected final int pageShift;
+ /** Bottom of region of memory allocated to the stack */
+ protected final int stackBottom;
/** Readable main memory pages */
- protected final int[][] readPages;
+ protected int[][] readPages;
/** Writable main memory pages.
If the page is writable writePages[x] == readPages[x]; if not writePages[x] == null. */
- protected final int[][] writePages;
+ protected int[][] writePages;
- /** The current break between the heap and unallocated memory */
- protected int brkAddr;
+ /** The address of the end of the heap */
+ private int heapEnd;
+
+ /** Number of guard pages to keep between the stack and the heap */
+ private static final int STACK_GUARD_PAGES = 4;
+
+ /** The last address the executable uses (other than the heap/stack) */
+ protected abstract int heapStart();
/** The program's entry point */
- protected int entryPoint;
+ protected abstract int entryPoint();
/** The location of the _user_info block (or 0 is there is none) */
- protected int userInfoBase;
- protected int userInfoSize;
+ protected int userInfoBase() { return 0; }
+ protected int userInfoSize() { return 0; }
/** The location of the global pointer */
- protected int gp;
+ protected abstract int gp();
/** When the process started */
private long startTime;
- /** State constant: There is no program loaded in memory */
- public final static int UNINITIALIZED = 0;
/** Text/Data loaded in memory */
- public final static int INITIALIZED = 1;
+ public final static int STOPPED = 0;
/** Program is executing instructions */
- public final static int RUNNING = 2;
+ public final static int RUNNING = 1;
/** Prgram has been started but is paused */
- public final static int PAUSED = 3;
+ public final static int PAUSED = 2;
/** Program is executing a callJava() method */
- public final static int CALLJAVA = 4;
+ public final static int CALLJAVA = 3;
/** Program has exited (it cannot currently be restarted) */
- public final static int DONE = 5;
-
- /** The current state (UNINITIALIZED, INITIALIZED, RUNNING, PAUSED, or DONE) */
- protected int state = UNINITIALIZED;
+ public final static int EXITED = 4;
+ /** Program has executed a successful exec(), a new Runtime needs to be run (used by UnixRuntime) */
+ public final static int EXECED = 5;
+
+ /** The current state */
+ protected int state = STOPPED;
/** @see Runtime#state state */
public final int getState() { return state; }
/** The exit status if the process (only valid if state==DONE)
@see Runtime#state */
- protected int exitStatus;
+ private int exitStatus;
public ExecutionException exitException;
- /** Maximum number of open file descriptors */
- final static int OPEN_MAX = 256;
/** Table containing all open file descriptors. (Entries are null if the fd is not in use */
- FD[] fds = new FD[OPEN_MAX];
+ FD[] fds = new FD[OPEN_MAX]; // package-private for UnixRuntime
+ boolean closeOnExec[] = new boolean[OPEN_MAX];
+
+ /** Pointer to a callback for the call_java syscall */
+ protected CallJavaCB callJavaCB;
+ public void setCallJavaCB(CallJavaCB callJavaCB) { this.callJavaCB = callJavaCB; }
+ public CallJavaCB getCallJavaCB() { return callJavaCB; }
/** Temporary buffer for read/write operations */
- private byte[] _byteBuf = null;
+ private byte[] _byteBuf;
/** Max size of temporary buffer
@see Runtime#_byteBuf */
- private final static int MAX_CHUNK = 15*1024*1024;
+ private final static int MAX_CHUNK = 16*1024*1024 - 1024;
/** Subclasses should actually execute program in this method. They should continue
executing until state != RUNNING. Only syscall() can modify state. It is safe
This method is only required if the call() function is used */
protected int lookupSymbol(String symbol) { return -1; }
- /** Subclasses should returns a CPUState object representing the cpu state */
- protected abstract CPUState getCPUState();
+ /** Subclasses should populate a CPUState object representing the cpu state */
+ protected abstract void getCPUState(CPUState state);
/** Subclasses should set the CPUState to the state held in <i>state</i> */
protected abstract void setCPUState(CPUState state);
-
- static void checkPageSize(int pageSize, int totalPages) throws IllegalArgumentException {
- if(pageSize < 256) throw new IllegalArgumentException("pageSize too small");
- if((pageSize&(pageSize-1)) != 0) throw new IllegalArgumentException("pageSize must be a power of two");
- if((totalPages&(totalPages-1)) != 0) throw new IllegalArgumentException("totalPages must be a power of two");
- if(totalPages != 1 && totalPages < 256) throw new IllegalArgumentException("totalPages too small");
- if(totalPages * pageSize < 4*1024*1024) throw new IllegalArgumentException("total memory too small (" + totalPages + "*" + pageSize + ")");
+
+ protected Object clone() throws CloneNotSupportedException {
+ Runtime r = (Runtime) super.clone();
+ r._byteBuf = null;
+ r.startTime = 0;
+ r.fds = new FD[OPEN_MAX];
+ for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) r.fds[i] = fds[i].dup();
+ int totalPages = writePages.length;
+ r.readPages = new int[totalPages][];
+ r.writePages = new int[totalPages][];
+ for(int i=0;i<totalPages;i++) {
+ if(readPages[i] == null) continue;
+ if(writePages[i] == null) r.readPages[i] = readPages[i];
+ else r.readPages[i] = r.writePages[i] = (int[])writePages[i].clone();
+ }
+ return r;
}
- protected Runtime(int pageSize, int totalPages, boolean allowEmptyPages) {
- this.allowEmptyPages = allowEmptyPages;
-
- checkPageSize(pageSize,totalPages);
-
- PAGE_SIZE = pageSize;
- PAGE_WORDS = pageSize>>>2;
- int pageShift = 0;
- while(pageSize>>>pageShift != 1) pageShift++;
- PAGE_SHIFT = pageShift;
-
- TOTAL_PAGES = totalPages;
-
- readPages = new int[TOTAL_PAGES][];
- writePages = new int[TOTAL_PAGES][];
+ protected Runtime(int pageSize, int totalPages) {
+ if(pageSize <= 0) throw new IllegalArgumentException("pageSize <= 0");
+ if(totalPages <= 0) throw new IllegalArgumentException("totalPages <= 0");
+ if((pageSize&(pageSize-1)) != 0) throw new IllegalArgumentException("pageSize not a power of two");
+
+ int _pageShift = 0;
+ while(pageSize>>>_pageShift != 1) _pageShift++;
+ pageShift = _pageShift;
- if(TOTAL_PAGES == 1) {
- readPages[0] = writePages[0] = new int[PAGE_WORDS];
- BRK_LIMIT = STACK_BOTTOM = 0;
+ int heapStart = heapStart();
+ int totalMemory = totalPages * pageSize;
+ int stackSize = max(totalMemory/64,ARG_MAX+65536);
+ int stackPages = 0;
+ if(totalPages > 1) {
+ stackSize = max(stackSize,pageSize);
+ stackSize = (stackSize + pageSize) & ~(pageSize-1);
+ stackPages = stackSize >>> pageShift;
+ heapStart = (heapStart + pageSize) & ~(pageSize-1);
+ if(stackPages + STACK_GUARD_PAGES + (heapStart >>> pageShift) >= totalPages)
+ throw new IllegalArgumentException("total pages too small");
} else {
- int stackPages = max(TOTAL_PAGES>>>8,(1024*1024)>>>PAGE_SHIFT);
- STACK_BOTTOM = (TOTAL_PAGES - stackPages) * PAGE_SIZE;
- // leave some unmapped pages between the stack and the heap
- BRK_LIMIT = STACK_BOTTOM - 4*PAGE_SIZE;
-
- for(int i=0;i<stackPages;i++)
- readPages[TOTAL_PAGES-1-i] = writePages[TOTAL_PAGES-1-i] = emptyPage();
+ if(pageSize < heapStart + stackSize) throw new IllegalArgumentException("total memory too small");
+ heapStart = (heapStart + 4095) & ~4096;
}
+ stackBottom = totalMemory - stackSize;
+ heapEnd = heapStart;
+
+ readPages = new int[totalPages][];
+ writePages = new int[totalPages][];
+
+ if(totalPages == 1)
+ readPages[0] = writePages[0] = new int[pageSize>>2];
+ else
+ for(int i=stackBottom >>> pageShift;i<writePages.length;i++)
+ readPages[i] = writePages[i] = new int[pageSize>>2];
+
addFD(new StdinFD(System.in));
addFD(new StdoutFD(System.out));
addFD(new StdoutFD(System.err));
/** Copy everything from <i>src</i> to <i>addr</i> initializing uninitialized pages if required.
Newly initalized pages will be marked read-only if <i>ro</i> is set */
protected final void initPages(int[] src, int addr, boolean ro) {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageMask = (1<<pageShift) - 1;
+
for(int i=0;i<src.length;) {
- int page = addr >>> PAGE_SHIFT;
- int start = (addr&(PAGE_SIZE-1))>>2;
- int elements = min(PAGE_WORDS-start,src.length-i);
+ int page = addr >>> pageShift;
+ int start = (addr&pageMask)>>2;
+ int elements = min(pageWords-start,src.length-i);
if(readPages[page]==null) {
initPage(page,ro);
} else if(!ro) {
/** Initialize <i>words</i> of pages starting at <i>addr</i> to 0 */
protected final void clearPages(int addr, int words) {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageMask = (1<<pageShift) - 1;
+
for(int i=0;i<words;) {
- int page = addr >>> PAGE_SHIFT;
- int start = (addr&(PAGE_SIZE-1))>>2;
- int elements = min(PAGE_WORDS-start,words-i);
+ int page = addr >>> pageShift;
+ int start = (addr&pageMask)>>2;
+ int elements = min(pageWords-start,words-i);
if(readPages[page]==null) {
- readPages[page] = writePages[page] = emptyPage();
+ readPages[page] = writePages[page] = new int[pageWords];
} else {
if(writePages[page] == null) writePages[page] = readPages[page];
for(int j=start;j<start+elements;j++) writePages[page][j] = 0;
/** Copies <i>length</i> bytes from the processes memory space starting at
<i>addr</i> INTO a java byte array <i>a</i> */
public final void copyin(int addr, byte[] buf, int count) throws ReadFaultException {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageMask = pageWords - 1;
+
int x=0;
+ if(count == 0) return;
if((addr&3)!=0) {
int word = memRead(addr&~3);
switch(addr&3) {
int c = count>>>2;
int a = addr>>>2;
while(c != 0) {
- int[] page = readPages[a >>> (PAGE_SHIFT-2)];
+ int[] page = readPages[a >>> (pageShift-2)];
if(page == null) throw new ReadFaultException(a<<2);
- int index = a&(PAGE_WORDS-1);
- int n = min(c,PAGE_WORDS-index);
- if(page != _emptyPage) {
- for(int i=0;i<n;i++,x+=4) {
- int word = page[index+i];
- buf[x+0] = (byte)((word>>>24)&0xff); buf[x+1] = (byte)((word>>>16)&0xff);
- buf[x+2] = (byte)((word>>> 8)&0xff); buf[x+3] = (byte)((word>>> 0)&0xff);
- }
+ int index = a&pageMask;
+ int n = min(c,pageWords-index);
+ for(int i=0;i<n;i++,x+=4) {
+ int word = page[index+i];
+ buf[x+0] = (byte)((word>>>24)&0xff); buf[x+1] = (byte)((word>>>16)&0xff);
+ buf[x+2] = (byte)((word>>> 8)&0xff); buf[x+3] = (byte)((word>>> 0)&0xff);
}
a += n; c -=n;
}
/** Copies <i>length</i> bytes OUT OF the java array <i>a</i> into the processes memory
space at <i>addr</i> */
public final void copyout(byte[] buf, int addr, int count) throws FaultException {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageWordMask = pageWords - 1;
+
int x=0;
+ if(count == 0) return;
if((addr&3)!=0) {
int word = memRead(addr&~3);
switch(addr&3) {
memWrite(addr&~3,word);
addr += x;
}
+
if((count&~3) != 0) {
int c = count>>>2;
int a = addr>>>2;
while(c != 0) {
- int[] page = writePages[a >>> (PAGE_SHIFT-2)];
+ int[] page = writePages[a >>> (pageShift-2)];
if(page == null) throw new WriteFaultException(a<<2);
- if(page == _emptyPage) page = initPage(a >>> (PAGE_SHIFT-2));
- int index = a&(PAGE_WORDS-1);
- int n = min(c,PAGE_WORDS-index);
+ int index = a&pageWordMask;
+ int n = min(c,pageWords-index);
for(int i=0;i<n;i++,x+=4)
page[index+i] = ((buf[x+0]&0xff)<<24)|((buf[x+1]&0xff)<<16)|((buf[x+2]&0xff)<<8)|((buf[x+3]&0xff)<<0);
a += n; c -=n;
}
addr = a<<2; count&=3;
}
+
if(count != 0) {
int word = memRead(addr);
switch(count) {
}
public final void memcpy(int dst, int src, int count) throws FaultException {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageWordMask = pageWords - 1;
+
if((dst&3) == 0 && (src&3)==0) {
if((count&~3) != 0) {
int c = count>>2;
int s = src>>>2;
int d = dst>>>2;
while(c != 0) {
- int[] srcPage = readPages[s>>>(PAGE_SHIFT-2)];
+ int[] srcPage = readPages[s>>>(pageShift-2)];
if(srcPage == null) throw new ReadFaultException(s<<2);
- int[] dstPage = writePages[d>>>(PAGE_SHIFT-2)];
+ int[] dstPage = writePages[d>>>(pageShift-2)];
if(dstPage == null) throw new WriteFaultException(d<<2);
- int srcIndex = (s&(PAGE_WORDS-1));
- int dstIndex = (d&(PAGE_WORDS-1));
- int n = min(c,PAGE_WORDS-max(srcIndex,dstIndex));
- if(srcPage != _emptyPage) {
- if(dstPage == _emptyPage) dstPage = initPage(d>>>(PAGE_SHIFT-2));
- System.arraycopy(srcPage,srcIndex,dstPage,dstIndex,n);
- } else if(srcPage == _emptyPage && dstPage != _emptyPage) {
- Arrays.fill(dstPage,dstIndex,dstIndex+n,0);
- }
+ int srcIndex = s&pageWordMask;
+ int dstIndex = d&pageWordMask;
+ int n = min(c,pageWords-max(srcIndex,dstIndex));
+ System.arraycopy(srcPage,srcIndex,dstPage,dstIndex,n);
s += n; d += n; c -= n;
}
src = s<<2; dst = d<<2; count&=3;
}
public final void memset(int addr, int ch, int count) throws FaultException {
+ int pageWords = (1<<pageShift)>>>2;
+ int pageWordMask = pageWords - 1;
+
int fourBytes = ((ch&0xff)<<24)|((ch&0xff)<<16)|((ch&0xff)<<8)|((ch&0xff)<<0);
if((addr&3)!=0) {
int word = memRead(addr&~3);
int c = count>>2;
int a = addr>>>2;
while(c != 0) {
- int[] page = readPages[a>>>(PAGE_SHIFT-2)];
+ int[] page = readPages[a>>>(pageShift-2)];
if(page == null) throw new WriteFaultException(a<<2);
- int index = (a&(PAGE_WORDS-1));
- int n = min(c,PAGE_WORDS-index);
- if(page != _emptyPage || ch != 0) {
- if(page == _emptyPage) page = initPage(a>>>(PAGE_SHIFT-2));
- Arrays.fill(page,index,index+n,fourBytes);
- }
+ int index = a&pageWordMask;
+ int n = min(c,pageWords-index);
+ Arrays.fill(page,index,index+n,fourBytes);
a += n; c -= n;
}
addr = a<<2; count&=3;
}
protected final int unsafeMemRead(int addr) throws ReadFaultException {
- int page = addr >>> PAGE_SHIFT;
- int entry = (addr >>> 2) & (PAGE_WORDS-1);
+ int page = addr >>> pageShift;
+ int entry = (addr&(1<<pageShift) - 1)>>2;
try {
return readPages[page][entry];
} catch(ArrayIndexOutOfBoundsException e) {
- if(page < 0) throw e; // should never happen
- if(page >= readPages.length) throw new ReadFaultException(addr);
- if(readPages[page] != _emptyPage) throw e; // should never happen
- initPage(page);
- return 0;
+ if(page < 0 || page >= readPages.length) throw new ReadFaultException(addr);
+ throw e; // should never happen
} catch(NullPointerException e) {
throw new ReadFaultException(addr);
}
}
protected final void unsafeMemWrite(int addr, int value) throws WriteFaultException {
- int page = addr >>> PAGE_SHIFT;
- int entry = (addr>>>2)&(PAGE_WORDS-1);
+ int page = addr >>> pageShift;
+ int entry = (addr&(1<<pageShift) - 1)>>2;
try {
writePages[page][entry] = value;
} catch(ArrayIndexOutOfBoundsException e) {
- if(page < 0) throw e;// should never happen
- if(page >= writePages.length) throw new WriteFaultException(addr);
- if(readPages[page] != _emptyPage) throw e; // should never happen
- initPage(page);
- writePages[page][entry] = value;
+ if(page < 0 || page >= writePages.length) throw new WriteFaultException(addr);
+ throw e; // should never happen
} catch(NullPointerException e) {
throw new WriteFaultException(addr);
}
private final int[] initPage(int page) { return initPage(page,false); }
/** Created a new non-empty page at page number <i>page</i>. If <i>ro</i> is set the page will be read-only */
private final int[] initPage(int page, boolean ro) {
- int[] buf = new int[PAGE_WORDS];
+ int[] buf = new int[(1<<pageShift)>>>2];
writePages[page] = ro ? null : buf;
readPages[page] = buf;
return buf;
/** Returns the exit status of the process. (only valid if state == DONE)
@see Runtime#state */
public final int exitStatus() {
- if(state != DONE) throw new IllegalStateException("exitStatus() called in an inappropriate state");
+ if(state != EXITED) throw new IllegalStateException("exitStatus() called in an inappropriate state");
return exitStatus;
}
- private int addStringArray(String[] strings, int topAddr) {
+ private int addStringArray(String[] strings, int topAddr) throws FaultException {
int count = strings.length;
int total = 0; /* null last table entry */
for(int i=0;i<count;i++) total += strings[i].length() + 1;
- if(total >= ARGS_MAX) throw new IllegalArgumentException("arguments/environ too big");
total += (count+1)*4;
int start = (topAddr - total)&~3;
int addr = start + (count+1)*4;
* and location of the user_info table from the ELF symbol table. setUserInfo and
* getUserInfo are used to modify the words in the user_info table. */
public void setUserInfo(int index, int word) {
- if(index < 0 || index >= userInfoSize/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize/4));
+ if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
try {
- memWrite(userInfoBase+index*4,word);
- } catch(FaultException e) { throw new Error("should never happen: " + e); }
+ memWrite(userInfoBase()+index*4,word);
+ } catch(FaultException e) { throw new RuntimeException(e.toString()); }
}
/** Returns the word in the _user_info table entry <i>index</i>
@see Runtime#setUserInfo(int,int) setUserInfo */
public int getUserInfo(int index) {
- if(index < 0 || index >= userInfoSize/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize/4));
+ if(index < 0 || index >= userInfoSize()/4) throw new IndexOutOfBoundsException("setUserInfo called with index >= " + (userInfoSize()/4));
try {
- return memRead(userInfoBase+index*4);
- } catch(FaultException e) { throw new Error("should never happen: " + e); }
+ return memRead(userInfoBase()+index*4);
+ } catch(FaultException e) { throw new RuntimeException(e.toString()); }
}
/** Calls _execute() (subclass's execute()) and catches exceptions */
if(startTime == 0) startTime = System.currentTimeMillis();
state = RUNNING;
__execute();
- if(state != PAUSED && state != DONE) throw new IllegalStateException("execute() ended up in an inappropriate state (" + state + ")");
- return state == DONE;
+ if(state != PAUSED && state != EXITED && state != EXECED)
+ throw new IllegalStateException("execute() ended up in an inappropriate state (" + state + ")");
+ return state != PAUSED;
}
- public final int run() { return run(null); }
- public final int run(String argv0, String[] rest) {
- String[] args = new String[rest.length+1];
- System.arraycopy(rest,0,args,1,rest.length);
- args[0] = argv0;
- return run(args);
+ protected static String[] concatArgv(String argv0, String[] rest) {
+ String[] argv = new String[rest.length+1];
+ System.arraycopy(rest,0,argv,1,rest.length);
+ argv[0] = argv0;
+ return argv;
}
+
+ public final int run() { return run(null); }
+ public final int run(String argv0, String[] rest) { return run(concatArgv(argv0,rest)); }
public final int run(String[] args) { return run(args,null); }
/** Runs the process until it exits and returns the exit status.
for(;;) {
if(execute()) break;
System.err.println("WARNING: Pause requested while executing run()");
- try { Thread.sleep(500); } catch(InterruptedException e) { /* noop */ }
}
- return exitStatus();
+ if(state == EXECED) System.err.println("WARNING: Process exec()ed while being run under run()");
+ return state == EXITED ? exitStatus() : 0;
}
public final void start() { start(null); }
/** Initializes the process and prepairs it to be executed with execute() */
public final void start(String[] args, String[] environ) {
- int sp, argsAddr, envAddr;
- if(state != INITIALIZED) throw new IllegalStateException("start() called in inappropriate state");
+ int top, sp, argsAddr, envAddr;
+ if(state != STOPPED) throw new IllegalStateException("start() called in inappropriate state");
if(args == null) args = new String[]{getClass().getName()};
- sp = TOTAL_PAGES*PAGE_SIZE-512;
- sp = argsAddr = addStringArray(args,sp);
- sp = envAddr = addStringArray(createEnv(environ),sp);
+ sp = top = writePages.length*(1<<pageShift);
+ try {
+ sp = argsAddr = addStringArray(args,sp);
+ sp = envAddr = addStringArray(createEnv(environ),sp);
+ } catch(FaultException e) {
+ throw new IllegalArgumentException("args/environ too big");
+ }
sp &= ~15;
-
+ if(top - sp > ARG_MAX) throw new IllegalArgumentException("args/environ too big");
+
CPUState cpuState = new CPUState();
cpuState.r[A0] = argsAddr;
cpuState.r[A1] = envAddr;
cpuState.r[SP] = sp;
cpuState.r[RA] = 0xdeadbeef;
- cpuState.r[GP] = gp;
- cpuState.pc = entryPoint;
+ cpuState.r[GP] = gp();
+ cpuState.pc = entryPoint();
setCPUState(cpuState);
-
+
state = PAUSED;
- _start();
+ _start();
}
/** Hook for subclasses to do their own startup */
protected void _start() { /* noop */ }
+ // FEATURE: call() that accepts an Object[] array and automatically allocates strings/arrays/etc on the stack
public final int call(String sym) throws CallException { return call(sym,0,0,0,0,0,0,0); }
public final int call(String sym, int a0) throws CallException { return call(sym,a0,0,0,0,0,0,0); }
public final int call(String sym, int a0, int a1) throws CallException { return call(sym,a0,a1,0,0,0,0,0); }
public final int call(int addr, int a0, int a1, int a2, int a3, int s0, int s1, int s2, int s3) {
if(state != PAUSED && state != CALLJAVA) throw new IllegalStateException("call() called in inappropriate state");
int oldState = state;
- CPUState saved = getCPUState();
- CPUState cpustate = new CPUState();
- cpustate.r[SP] = saved.r[SP]&~15;
+ CPUState saved = new CPUState();
+ getCPUState(saved);
+ CPUState cpustate = saved.dup();
+
+ cpustate.r[SP] = cpustate.r[SP]&~15;
cpustate.r[RA] = 0xdeadbeef;
cpustate.r[A0] = a0;
cpustate.r[A1] = a1;
cpustate.r[S1] = s1;
cpustate.r[S2] = s2;
cpustate.r[S3] = s3;
- cpustate.r[GP] = gp;
cpustate.pc = addr;
state = RUNNING;
setCPUState(cpustate);
__execute();
- cpustate = getCPUState();
+ getCPUState(cpustate);
setCPUState(saved);
if(state != PAUSED)
return cpustate.r[V1];
}
- // FEATURE: This is ugly - we should have some kind of way to specify a callback rather than requiring subclassing
- protected int callJava(int a, int b, int c, int d) {
- System.err.println("WARNING: Default implementation of callJava() called with args " + toHex(a) + "," + toHex(b) + "," + toHex(c) + "," + toHex(d));
- return 0;
- }
-
/** Determines if the process can access <i>fileName</i>. The default implementation simply logs
the request and allows it */
protected boolean allowFileAccess(String fileName, boolean write) {
Returns -1 if the table is full. This can be used by subclasses to use custom file
descriptors */
public int addFD(FD fd) {
+ if(state == EXITED || state == EXECED) throw new IllegalStateException("addFD called in inappropriate state");
int i;
for(i=0;i<OPEN_MAX;i++) if(fds[i] == null) break;
if(i==OPEN_MAX) return -1;
fds[i] = fd;
+ closeOnExec[i] = false;
return i;
}
/** Closes file descriptor <i>fdn</i> and removes it from the file descriptor table */
public boolean closeFD(int fdn) {
+ if(state == EXITED || state == EXECED) throw new IllegalStateException("closeFD called in inappropriate state");
if(fdn < 0 || fdn >= OPEN_MAX) return false;
if(fds[fdn] == null) return false;
fds[fdn].close();
<i>incr</i> is how much to increase the break by */
public int sbrk(int incr) {
if(incr < 0) return -ENOMEM;
- if(incr==0) return brkAddr;
+ if(incr==0) return heapEnd;
incr = (incr+3)&~3;
- int oldBrk = brkAddr;
- int newBrk = oldBrk + incr;
- if(TOTAL_PAGES == 1) {
- CPUState state = getCPUState();
- if(newBrk >= state.r[SP] - 65536) {
- System.err.println("WARNING: brk too close to stack pointer");
- return -ENOMEM;
- }
- } else if(newBrk >= BRK_LIMIT) {
- System.err.println("WARNING: Hit BRK_LIMIT");
- return -ENOMEM;
- }
- if(TOTAL_PAGES != 1) {
+ int oldEnd = heapEnd;
+ int newEnd = oldEnd + incr;
+ if(newEnd >= stackBottom) return -ENOMEM;
+
+ if(writePages.length > 1) {
+ int pageMask = (1<<pageShift) - 1;
+ int pageWords = (1<<pageShift) >>> 2;
+ int start = (oldEnd + pageMask) >>> pageShift;
+ int end = (newEnd + pageMask) >>> pageShift;
try {
- for(int i=(oldBrk+PAGE_SIZE-1)>>>PAGE_SHIFT;i<((newBrk+PAGE_SIZE-1)>>>PAGE_SHIFT);i++)
- readPages[i] = writePages[i] = emptyPage();
+ for(int i=start;i<end;i++) readPages[i] = writePages[i] = new int[pageWords];
} catch(OutOfMemoryError e) {
System.err.println("WARNING: Caught OOM Exception in sbrk: " + e);
return -ENOMEM;
}
}
- brkAddr = newBrk;
- return oldBrk;
+ heapEnd = newEnd;
+ return oldEnd;
}
/** The getpid syscall */
private int sys_getpid() { return getPid(); }
protected int getPid() { return 1; }
+ public static interface CallJavaCB { public int call(int a, int b, int c, int d); }
+
private int sys_calljava(int a, int b, int c, int d) {
if(state != RUNNING) throw new IllegalStateException("wound up calling sys_calljava while not in RUNNING");
- state = CALLJAVA;
- int ret = callJava(a,b,c,d);
- state = RUNNING;
- return ret;
+ if(callJavaCB != null) {
+ state = CALLJAVA;
+ int ret = callJavaCB.call(a,b,c,d);
+ state = RUNNING;
+ return ret;
+ } else {
+ System.err.println("WARNING: calljava syscall invoked without a calljava callback set");
+ return 0;
+ }
}
private int sys_pause() {
return 0;
}
- private int sys_getpagesize() { return TOTAL_PAGES == 1 ? 4096 : PAGE_SIZE; }
+ private int sys_getpagesize() { return writePages.length == 1 ? 4096 : (1<<pageShift); }
private int sys_isatty(int fdn) {
if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
}
- /** Hook for subclasses to do something when the process exits (MUST set state = DONE) */
- protected void _exit() { state = DONE; }
+ /** Hook for subclasses to do something when the process exits (MUST set state = EXITED) */
+ protected void _exit() { state = EXITED; }
private int sys_exit(int status) {
exitStatus = status;
- for(int i=0;i<fds.length;i++) if(fds[i] != null) sys_close(i);
+ for(int i=0;i<fds.length;i++) if(fds[i] != null) closeFD(i);
_exit();
return 0;
}
private int sys_fcntl(int fdn, int cmd, int arg) {
+ // FEATURE: Pull these from fcntl.h
final int F_DUPFD = 0;
+ final int F_GETFD = 1;
+ final int F_SETFD = 2;
final int F_GETFL = 3;
int i;
if(fd.writable() && fd.readable()) flags = 2;
else if(fd.writable()) flags = 1;
return flags;
+ case F_SETFD:
+ closeOnExec[fdn] = arg != 0;
+ return 0;
+ case F_GETFD:
+ return closeOnExec[fdn] ? 1 : 0;
default:
System.err.println("WARNING: Unknown fcntl command: " + cmd);
return -ENOSYS;
public int seek(int n, int whence) throws IOException { return -1; }
/** Should return true if this is a tty */
+ // FEATURE: get rid of the isatty syscall and just do with newlib's dumb isatty.c
public boolean isatty() { return false; }
private FStat cachedFStat = null;
private final boolean executable;
public HostFStat(File f) {
this.f = f;
- String name = f.getName();
- // FEATURE: This is ugly.. maybe we should do a file(1) type check
- executable = name.endsWith(".mips") || name.endsWith(".sh");
+ boolean _executable = false;
+ // FEATURE: This might be too expensive
+ try {
+ FileInputStream fis = new FileInputStream(f);
+ switch(fis.read()) {
+ case '\177': _executable = fis.read() == 'E' && fis.read() == 'L' && fis.read() == 'F'; break;
+ case '#': _executable = fis.read() == '!';
+ }
+ fis.close();
+ } catch(IOException e) { /* ignore */ }
+ executable = _executable;
}
public int dev() { return 1; }
public int inode() { return f.getName().hashCode() & 0xffff; }
public int hi, lo;
public int fcsr;
public int pc;
+
+ public CPUState dup() {
+ CPUState c = new CPUState();
+ c.hi = hi;
+ c.lo = lo;
+ c.fcsr = fcsr;
+ c.pc = pc;
+ for(int i=0;i<32;i++) {
+ c.r[i] = r[i];
+ c.f[i] = f[i];
+ }
+ return c;
+ }
}
// Null pointer check helper function
protected final void nullPointerCheck(int addr) throws ExecutionException {
- if(TOTAL_PAGES==1 ? addr < 65536 : (addr>>>PAGE_SHIFT) < 16)
+ if(addr < 65536)
throw new ExecutionException("Attempted to dereference a null pointer " + toHex(addr));
}
projects / nestedvm.git / blobdiff