wip: refactoring and remove sigint handling

rust/ares/src/interpreter.rs

@@ -332,7 +332,6 @@ pub enum GuardError {
     GuardArmor = GUARD_ARMOR as isize,
     GuardWeird = GUARD_WEIRD as isize,
     GuardSpent = GUARD_SPENT as isize,
-    GuardErupt = GUARD_ERUPT as isize,
 }
 
 impl TryFrom<u32> for GuardError {
@@ -343,7 +342,6 @@ impl TryFrom<u32> for GuardError {
             GUARD_ARMOR => Ok(GuardError::GuardArmor),
             GUARD_WEIRD => Ok(GuardError::GuardWeird),
             GUARD_SPENT => Ok(GuardError::GuardSpent),
-            GUARD_ERUPT => Ok(GuardError::GuardErupt),
             _ => Err(()),
         }
     }
@@ -523,8 +521,6 @@ pub fn call_with_guard<
             ret_pp,
         );
 
-        eprint!("call_with_guard: error: {}\n", guard_error);
-
         if let Ok(err) = GuardError::try_from(guard_error) {
             match err {
                 GuardError::GuardSound => {
@@ -535,7 +531,8 @@ pub fn call_with_guard<
                     })
                 }
                 GuardError::GuardArmor => {
-                    return Err(Error::Deterministic(Mote::Exit, D(0)));
+                    // XX
+                    panic!("guard: couldn't place guard page\r\n");
                 }
                 GuardError::GuardWeird => {
                     return Err(Error::Deterministic(Mote::Exit, D(0)));
@@ -543,9 +540,6 @@ pub fn call_with_guard<
                 GuardError::GuardSpent => {
                     return Err(Error::NonDeterministic(Mote::Meme, D(0)));
                 }
-                GuardError::GuardErupt => {
-                    return Err(Error::NonDeterministic(Mote::Intr, D(0)));
-                }
             }
         } else {
             return Err(Error::Deterministic(Mote::Exit, D(0)));

rust/ares/src/serf.rs

@@ -143,7 +143,7 @@ impl Context {
         snapshot: Option<Snapshot>,
         constant_hot_state: &[HotEntry],
     ) -> Self {
-        let mut stack = NockStack::new(128 << 10 << 10, 0);
+        let mut stack = NockStack::new(64 << 10 << 10, 0);
         let newt = Newt::new();
         let cache = Hamt::<Noun>::new(&mut stack);
 

rust/ares_guard/c-src/guard.c

@@ -14,9 +14,7 @@
 
 static uint64_t *guard_p = 0;
 static jmp_buf env_buffer;
-volatile sig_atomic_t err = guard_sound;
 static void (*prev_sigsegv_handler)(int, siginfo_t *, void *);
-
 static const uint64_t *(*low)(void *, void *) = 0;
 static const uint64_t *(*high)(void *, void *) = 0;
 static void *bounds = 0;
@@ -29,33 +27,20 @@ _focus_guard()
   const uint64_t *low_p = low(bounds, context);
   const uint64_t *high_p = high(bounds, context);
 
-  // Check if we're spent already.
-  if (low_p == high_p || low_p > high_p) {
+  if (low_p >= high_p ) {
     return guard_spent;
   }
 
-  // Check for strange situations.
   if (low_p == 0 || high_p == 0) {
     fprintf(stderr, "guard: low or high bound pointer is null\r\n");
     return guard_weird;
   }
 
-  // Unmark the old guard page if one exists.
   void *old_guard_p = guard_p;
-  if (old_guard_p != NULL) {
-    fprintf(stderr, "guard: retiring old guard page\r\n");
-    if (old_guard_p != 0
-        && mprotect(old_guard_p, GD_PAGESIZE, PROT_READ | PROT_WRITE) == -1) {
-      return guard_armor;
-    }
-  }
 
-  // Calculate the new center for the guard page.
   guard_p = (uint64_t *)low_p + ((high_p - low_p) / 2);
   guard_p = (uint64_t *)((uintptr_t)guard_p & ~(GD_PAGESIZE - 1));
 
-  // Place the new guard page or return if we're spent.
-  bool spent = false;
   const bool same = old_guard_p == guard_p;
   const bool left = (high_p - low_p) > GD_PAGESIZE;
   if (same && !left) {
@@ -63,62 +48,51 @@ _focus_guard()
     return guard_spent;
   }
   else {
-    fprintf(stderr, "guard: high: %p; low: %p\r\n", high_p, low_p);
-    fprintf(stderr, "guard: focused: %p; left: %u\r\n", guard_p, left);
     if (mprotect(guard_p, GD_PAGESIZE, PROT_NONE) == -1) {
       return guard_armor;
     }
   }
 
+  if (old_guard_p != NULL && 
+      mprotect(old_guard_p, GD_PAGESIZE, PROT_READ | PROT_WRITE) == -1)
+  {
+    return guard_armor;
+  }
+
   return guard_sound;
 }
 
 static void
 _signal_handler(int sig, siginfo_t *si, void *unused)
 {
+  if (sig != SIGSEGV) {
+    fprintf(stderr, "guard: weird signal: %d\r\n", sig);
+    return;
+  }
+
   if (guard_p == NULL) {
     fprintf(stderr, "guard: no guard page\r\n");
-    err = guard_weird;
     return;
   }
 
   if (si == NULL) {
     fprintf(stderr, "guard: no signal info\r\n");
-    err = guard_weird;
     return;
   }
 
-  switch (sig) {
-    case SIGSEGV:
   if (si->si_addr >= (void *)guard_p && 
       si->si_addr <  (void *)guard_p + GD_PAGESIZE)
   {
     fprintf(stderr, "guard: hit: %p\r\n", si->si_addr);
-        err = _focus_guard();
-        break;
+    guard_err err = _focus_guard();
+    if (err != guard_sound) {
+      fprintf(stderr, "guard: jump\r\n");
+      siglongjmp(env_buffer, err);
+    }
   }
   else {
     fprintf(stderr, "guard: weird hit: %p\r\n", si->si_addr);
-        if (NULL != prev_sigsegv_handler) {
-          prev_sigsegv_handler(sig, si, unused);
-          break;
-        }
-        else { 
-          err = guard_weird;
-        }
-      }
-      break;
-    case SIGINT:
-      fprintf(stderr, "guard: sigint\r\n");
-      err = guard_erupt;
-      break;
-    default:
-      break;
-  }
-
-  if (err != guard_sound) {
-    fprintf(stderr, "guard: long jumping\r\n");
-    siglongjmp(env_buffer, 1);
+    return;
   }
 }
 
@@ -152,69 +126,44 @@ guard(
   void *const *ret
 )
 {
-  // Set globals.
+  guard_err err;
+
   low = low_f;
   high = high_f;
   bounds= bounds_data;
   context = context_p;
 
-  const uint64_t *low_p = low_f(bounds_data, context_p);
-  const uint64_t *high_p = high_f(bounds_data, context_p);
-
-  if (guard_p == NULL) {
-    guard_err focus_err = _focus_guard();
-    if (focus_err != guard_sound && focus_err != guard_spent) {
-      fprintf(stderr, "guard: failed to install guard page\r\n");
-      err = focus_err;
-      goto fail;
-    }
-  }
-
-  if (_register_handler() != guard_sound) {
-    err = guard_weird;
+  err = _focus_guard();
+  if (guard_p == NULL && err != guard_sound && err != guard_spent) {
+    fprintf(stderr, "guard: failed to install\r\n");
     goto fail;
   }
 
-  void *result;
-  if (sigsetjmp(env_buffer, 1) == 0) {
-    result = work_f(work_data, context_p);
-    *(void **)ret = result;
+  if ((err = _register_handler()) != guard_sound) {
+    fprintf(stderr, "guard: failed to register handler\r\n");
+    goto fail;
+  }
+
+  err = sigsetjmp(env_buffer, 1);
+  if (err == guard_start) {
+    *(void **)ret = work_f(work_data, context_p);
     return guard_sound;
   }
   else {
-    if (err != guard_sound) {
     goto fail; 
   }
-  }
 
 fail:
-  if (guard_p != NULL && 
-      mprotect(guard_p, GD_PAGESIZE, PROT_READ | PROT_WRITE) == -1)
-  {
-    fprintf(stderr, "guard: failed to uninstall guard page\r\n");
-  }
-
   // Restore the previous signal handler.
+  {
     struct sigaction sa;
     sa.sa_flags = SA_SIGINFO;
     sa.sa_sigaction = prev_sigsegv_handler;
     sigemptyset(&sa.sa_mask);
     sigaddset(&(sa.sa_mask), SIGSEGV);
     sigaction(SIGSEGV, &sa, NULL);
-  
-  switch (err) {
-    case guard_armor:
-      fprintf(stderr, "guard: armor error\r\n");
-      break;
-    case guard_weird:
-      fprintf(stderr, "guard: weird error\r\n");
-      break;
-    case guard_spent:
-      fprintf(stderr, "guard: spent error\r\n");
-      break;
-    case guard_erupt:
-      fprintf(stderr, "guard: erupt error\r\n");
-      break;
   }
+  
+  fprintf(stderr, "guard: fail: %d\r\n", err);
   return err;
 }

rust/ares_guard/c-src/guard.h

@@ -5,11 +5,11 @@
 
 
 typedef enum {
-  guard_sound = 0, // job's done
-  guard_armor = 1, // mprotect
-  guard_weird = 2, // strange state
-  guard_spent = 3, // out of memory (bail:meme)
-  guard_erupt = 4, // sigint
+  guard_start = 0, // setjmp
+  guard_sound = 1, // good/done
+  guard_armor = 2, // mprotect
+  guard_weird = 3, // strange state
+  guard_spent = 4, // out of memory (bail:meme)
 } guard_err;
 
 /**

rust/ares_guard/src/lib.rs

@@ -8,4 +8,3 @@ pub const GUARD_SOUND: u32 = guard_err_guard_sound;
 pub const GUARD_ARMOR: u32 = guard_err_guard_armor; 
 pub const GUARD_WEIRD: u32 = guard_err_guard_weird;
 pub const GUARD_SPENT: u32 = guard_err_guard_spent;
-pub const GUARD_ERUPT: u32 = guard_err_guard_erupt;