Bug 1159972 - Remove the fallible version of PL_DHashTableInit(). r=f…

…roydnj.

It's no longer needed now that entry storage isn't allocated there. (The other
possible causes of failures in that function are less interesting and simply
crashing is a reasonable thing to do for them.)

This also makes PL_DNewHashTable() infallible, so I removed some
now-unnecessary checks of its result.

dom/base/nsDocument.cpp

@@ -4047,9 +4047,6 @@ nsDocument::SetSubDocumentFor(Element* aElement, nsIDocument* aSubDoc)
       };
 
       mSubDocuments = PL_NewDHashTable(&hash_table_ops, sizeof(SubDocMapEntry));
-      if (!mSubDocuments) {
-        return NS_ERROR_OUT_OF_MEMORY;
-      }
     }
 
     // Add a mapping to the hash table

dom/base/nsScriptNameSpaceManager.cpp

@@ -323,21 +323,15 @@ nsScriptNameSpaceManager::Init()
     GlobalNameHashInitEntry
   };
 
-  mIsInitialized = PL_DHashTableInit(&mGlobalNames, &hash_table_ops,
-                                     sizeof(GlobalNameMapEntry),
-                                     fallible,
-                                     GLOBALNAME_HASHTABLE_INITIAL_LENGTH);
-  NS_ENSURE_TRUE(mIsInitialized, NS_ERROR_OUT_OF_MEMORY);
-
-  mIsInitialized = PL_DHashTableInit(&mNavigatorNames, &hash_table_ops,
-                                     sizeof(GlobalNameMapEntry),
-                                     fallible,
-                                     GLOBALNAME_HASHTABLE_INITIAL_LENGTH);
-  if (!mIsInitialized) {
-    PL_DHashTableFinish(&mGlobalNames);
+  PL_DHashTableInit(&mGlobalNames, &hash_table_ops,
+                    sizeof(GlobalNameMapEntry),
+                    GLOBALNAME_HASHTABLE_INITIAL_LENGTH);
 
-    return NS_ERROR_OUT_OF_MEMORY;
-  }
+  PL_DHashTableInit(&mNavigatorNames, &hash_table_ops,
+                    sizeof(GlobalNameMapEntry),
+                    GLOBALNAME_HASHTABLE_INITIAL_LENGTH);
+
+  mIsInitialized = true;
 
   RegisterWeakMemoryReporter(this);
 

dom/xul/XULDocument.cpp

@@ -769,11 +769,6 @@ XULDocument::AddBroadcastListenerFor(Element& aBroadcaster, Element& aListener,
 
     if (! mBroadcasterMap) {
         mBroadcasterMap = PL_NewDHashTable(&gOps, sizeof(BroadcasterMapEntry));
-
-        if (! mBroadcasterMap) {
-            aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
-            return;
-        }
     }
 
     BroadcasterMapEntry* entry =

layout/style/nsRuleNode.cpp

@@ -1617,8 +1617,6 @@ nsRuleNode::ConvertChildrenToHash(int32_t aNumKids)
   PLDHashTable *hash = PL_NewDHashTable(&ChildrenHashOps,
                                         sizeof(ChildrenHashEntry),
                                         aNumKids);
-  if (!hash)
-    return;
   for (nsRuleNode* curr = ChildrenList(); curr; curr = curr->mNextSibling) {
     // This will never fail because of the initial size we gave the table.
     ChildrenHashEntry *entry = static_cast<ChildrenHashEntry*>(

modules/libpref/prefapi.cpp

@@ -149,11 +149,8 @@ static nsresult pref_HashPref(const char *key, PrefValue value, PrefType type, u
 nsresult PREF_Init()
 {
     if (!gHashTable.IsInitialized()) {
-        if (!PL_DHashTableInit(&gHashTable, &pref_HashTableOps,
-                               sizeof(PrefHashEntry), fallible,
-                               PREF_HASHTABLE_INITIAL_LENGTH)) {
-            return NS_ERROR_OUT_OF_MEMORY;
-        }
+        PL_DHashTableInit(&gHashTable, &pref_HashTableOps,
+                          sizeof(PrefHashEntry), PREF_HASHTABLE_INITIAL_LENGTH);
 
         PL_INIT_ARENA_POOL(&gPrefNameArena, "PrefNameArena",
                            PREFNAME_ARENA_SIZE);

netwerk/cache/nsCacheEntry.cpp

@@ -402,14 +402,9 @@ nsCacheEntryHashTable::~nsCacheEntryHashTable()
 nsresult
 nsCacheEntryHashTable::Init()
 {
-    nsresult rv = NS_OK;
-    initialized = PL_DHashTableInit(&table, &ops,
-                                    sizeof(nsCacheEntryHashTableEntry),
-                                    fallible, 256);
-
-    if (!initialized) rv = NS_ERROR_OUT_OF_MEMORY;
-
-    return rv;
+    PL_DHashTableInit(&table, &ops, sizeof(nsCacheEntryHashTableEntry), 256);
+    initialized = true;
+    return NS_OK;
 }
 
 void

netwerk/protocol/http/nsHttp.cpp

@@ -105,10 +105,8 @@ nsHttp::CreateAtomTable()
     // The initial length for this table is a value greater than the number of
     // known atoms (NUM_HTTP_ATOMS) because we expect to encounter a few random
     // headers right off the bat.
-    if (!PL_DHashTableInit(&sAtomTable, &ops, sizeof(PLDHashEntryStub),
-                           fallible, NUM_HTTP_ATOMS + 10)) {
-        return NS_ERROR_OUT_OF_MEMORY;
-    }
+    PL_DHashTableInit(&sAtomTable, &ops, sizeof(PLDHashEntryStub),
+                      NUM_HTTP_ATOMS + 10);
 
     // fill the table with our known atoms
     const char *const atoms[] = {

parser/htmlparser/nsHTMLEntities.cpp

@@ -83,17 +83,10 @@ nsresult
 nsHTMLEntities::AddRefTable(void)
 {
   if (!gTableRefCnt) {
-    if (!PL_DHashTableInit(&gEntityToUnicode, &EntityToUnicodeOps,
-                           sizeof(EntityNodeEntry),
-                           fallible, NS_HTML_ENTITY_COUNT)) {
-      return NS_ERROR_OUT_OF_MEMORY;
-    }
-    if (!PL_DHashTableInit(&gUnicodeToEntity, &UnicodeToEntityOps,
-                           sizeof(EntityNodeEntry),
-                           fallible, NS_HTML_ENTITY_COUNT)) {
-      PL_DHashTableFinish(&gEntityToUnicode);
-      return NS_ERROR_OUT_OF_MEMORY;
-    }
+    PL_DHashTableInit(&gEntityToUnicode, &EntityToUnicodeOps,
+                      sizeof(EntityNodeEntry), NS_HTML_ENTITY_COUNT);
+    PL_DHashTableInit(&gUnicodeToEntity, &UnicodeToEntityOps,
+                      sizeof(EntityNodeEntry), NS_HTML_ENTITY_COUNT);
     for (const EntityNode *node = gEntityArray,
                  *node_end = ArrayEnd(gEntityArray);
          node < node_end; ++node) {

security/manager/ssl/src/nsCertTree.cpp

@@ -175,10 +175,8 @@ void nsCertTree::ClearCompareHash()
 nsresult nsCertTree::InitCompareHash()
 {
   ClearCompareHash();
-  if (!PL_DHashTableInit(&mCompareCache, &gMapOps,
-                         sizeof(CompareCacheHashEntryPtr), fallible, 64)) {
-    return NS_ERROR_OUT_OF_MEMORY;
-  }
+  PL_DHashTableInit(&mCompareCache, &gMapOps,
+                    sizeof(CompareCacheHashEntryPtr), 64);
   return NS_OK;
 }
 

xpcom/ds/nsStaticNameTable.cpp

@@ -138,11 +138,8 @@ nsStaticCaseInsensitiveNameTable::Init(const char* const aNames[],
     return false;
   }
 
-  if (!PL_DHashTableInit(&mNameTable, &nametable_CaseInsensitiveHashTableOps,
-                         sizeof(NameTableEntry), fallible,
-                         aLength)) {
-    return false;
-  }
+  PL_DHashTableInit(&mNameTable, &nametable_CaseInsensitiveHashTableOps,
+                    sizeof(NameTableEntry), aLength);
 
   for (int32_t index = 0; index < aLength; ++index) {
     const char* raw = aNames[index];

xpcom/glue/pldhash.cpp

@@ -174,10 +174,7 @@ PL_NewDHashTable(const PLDHashTableOps* aOps, uint32_t aEntrySize,
                  uint32_t aLength)
 {
   PLDHashTable* table = new PLDHashTable();
-  if (!PL_DHashTableInit(table, aOps, aEntrySize, fallible, aLength)) {
-    delete table;
-    return nullptr;
-  }
+  PL_DHashTableInit(table, aOps, aEntrySize, aLength);
   return table;
 }
 
@@ -217,9 +214,9 @@ MinCapacity(uint32_t aLength)
   return (aLength * 4 + (3 - 1)) / 3;   // == ceil(aLength * 4 / 3)
 }
 
-MOZ_ALWAYS_INLINE bool
+MOZ_ALWAYS_INLINE void
 PLDHashTable::Init(const PLDHashTableOps* aOps,
-                   uint32_t aEntrySize, const fallible_t&, uint32_t aLength)
+                   uint32_t aEntrySize, uint32_t aLength)
 {
   MOZ_ASSERT(!IsInitialized());
 
@@ -229,7 +226,7 @@ PLDHashTable::Init(const PLDHashTableOps* aOps,
   MOZ_ASSERT(mEntryStore == nullptr);
 
   if (aLength > PL_DHASH_MAX_INITIAL_LENGTH) {
-    return false;
+    MOZ_CRASH("Initial length is too large");
   }
 
   // Compute the smallest capacity allowing |aLength| elements to be inserted
@@ -243,51 +240,30 @@ PLDHashTable::Init(const PLDHashTableOps* aOps,
 
   capacity = 1u << log2;
   MOZ_ASSERT(capacity <= PL_DHASH_MAX_CAPACITY);
+  mOps = aOps;
   mHashShift = PL_DHASH_BITS - log2;
   mEntrySize = aEntrySize;
   mEntryCount = mRemovedCount = 0;
   mGeneration = 0;
   uint32_t nbytes;
   if (!SizeOfEntryStore(capacity, aEntrySize, &nbytes)) {
-    return false;  // overflowed
+    MOZ_CRASH("Initial entry store size is too large");
   }
 
   mEntryStore = nullptr;
 
   METER(memset(&mStats, 0, sizeof(mStats)));
 
-  // Set this only once we reach a point where we know we can't fail.
-  mOps = aOps;
-
 #ifdef DEBUG
   mRecursionLevel = 0;
 #endif
-
-  return true;
-}
-
-bool
-PL_DHashTableInit(PLDHashTable* aTable, const PLDHashTableOps* aOps,
-                  uint32_t aEntrySize,
-                  const fallible_t& aFallible, uint32_t aLength)
-{
-  return aTable->Init(aOps, aEntrySize, aFallible, aLength);
 }
 
 void
 PL_DHashTableInit(PLDHashTable* aTable, const PLDHashTableOps* aOps,
                   uint32_t aEntrySize, uint32_t aLength)
 {
-  if (!PL_DHashTableInit(aTable, aOps, aEntrySize, fallible, aLength)) {
-    if (aLength > PL_DHASH_MAX_INITIAL_LENGTH) {
-      MOZ_CRASH();          // the asked-for length was too big
-    }
-    uint32_t capacity = MinCapacity(aLength), nbytes;
-    if (!SizeOfEntryStore(capacity, aEntrySize, &nbytes)) {
-      MOZ_CRASH();          // the required mEntryStore size was too big
-    }
-    NS_ABORT_OOM(nbytes);   // allocation failed
-  }
+  aTable->Init(aOps, aEntrySize, aLength);
 }
 
 /*

xpcom/glue/pldhash.h

@@ -269,8 +269,7 @@ class PLDHashTable
   uint32_t EntryCount() const { return mEntryCount; }
   uint32_t Generation() const { return mGeneration; }
 
-  bool Init(const PLDHashTableOps* aOps, uint32_t aEntrySize,
-            const mozilla::fallible_t&, uint32_t aLength);
+  void Init(const PLDHashTableOps* aOps, uint32_t aEntrySize, uint32_t aLength);
 
   void Finish();
 
@@ -467,7 +466,7 @@ const PLDHashTableOps* PL_DHashGetStubOps(void);
 
 /*
  * Dynamically allocate a new PLDHashTable, initialize it using
- * PL_DHashTableInit, and return its address. Return null on allocation failure.
+ * PL_DHashTableInit, and return its address. Never returns null.
  */
 PLDHashTable* PL_NewDHashTable(
   const PLDHashTableOps* aOps, uint32_t aEntrySize,
@@ -494,15 +493,6 @@ void PL_DHashTableInit(
   PLDHashTable* aTable, const PLDHashTableOps* aOps,
   uint32_t aEntrySize, uint32_t aLength = PL_DHASH_DEFAULT_INITIAL_LENGTH);
 
-/*
- * Initialize aTable. This is the same as PL_DHashTableInit, except that it
- * returns a boolean indicating success, rather than crashing on failure.
- */
-MOZ_WARN_UNUSED_RESULT bool PL_DHashTableInit(
-  PLDHashTable* aTable, const PLDHashTableOps* aOps,
-  uint32_t aEntrySize, const mozilla::fallible_t&,
-  uint32_t aLength = PL_DHASH_DEFAULT_INITIAL_LENGTH);
-
 /*
  * Free |aTable|'s entry storage (via aTable->mOps->freeTable). Use this
  * function to destroy a PLDHashTable that is allocated on the stack or in

xpcom/tests/TestPLDHash.cpp

@@ -22,12 +22,20 @@ static bool test_pldhash_Init_capacity_ok()
   }
 
   // Try the largest allowed capacity.  With PL_DHASH_MAX_CAPACITY==1<<26, this
-  // will allocate 0.5GB of entry store on 32-bit platforms and 1GB on 64-bit
-  // platforms.
-  if (!PL_DHashTableInit(&t, PL_DHashGetStubOps(), sizeof(PLDHashEntryStub),
-                         mozilla::fallible, PL_DHASH_MAX_INITIAL_LENGTH)) {
-    return false;
-  }
+  // would allocate (if we added an element) 0.5GB of entry store on 32-bit
+  // platforms and 1GB on 64-bit platforms.
+  //
+  // Ideally we'd also try (a) a too-large capacity, and (b) a large capacity
+  // combined with a large entry size that when multipled overflow. But those
+  // cases would cause the test to abort immediately.
+  //
+  // Furthermore, ideally we'd also try a large-but-ok capacity that almost but
+  // doesn't quite overflow, but that would result in allocating just under 4GB
+  // of entry storage.  That's very likely to fail on 32-bit platforms, so such
+  // a test wouldn't be reliable.
+  //
+  PL_DHashTableInit(&t, PL_DHashGetStubOps(), sizeof(PLDHashEntryStub),
+                    PL_DHASH_MAX_INITIAL_LENGTH);
 
   // Check that Init() sets |ops|.
   if (!t.IsInitialized()) {
@@ -43,67 +51,6 @@ static bool test_pldhash_Init_capacity_ok()
   return true;
 }
 
-static bool test_pldhash_Init_capacity_too_large()
-{
-  PLDHashTable t;
-
-  // Check that the constructor nulls |ops|.
-  if (t.IsInitialized()) {
-    return false;
-  }
-
-  // Try the smallest too-large capacity.
-  if (PL_DHashTableInit(&t, PL_DHashGetStubOps(),
-                        sizeof(PLDHashEntryStub),
-                        mozilla::fallible,
-                        PL_DHASH_MAX_INITIAL_LENGTH + 1)) {
-    return false;   // it succeeded!?
-  }
-  // Don't call PL_DHashTableFinish() here; it's not safe after Init() failure.
-
-  // Check that |ops| is still null.
-  if (t.IsInitialized()) {
-    return false;
-  }
-
-  return true;
-}
-
-static bool test_pldhash_Init_overflow()
-{
-  PLDHashTable t;
-
-  // Check that the constructor nulls |ops|.
-  if (t.IsInitialized()) {
-    return false;
-  }
-
-  // Try an acceptable capacity, but one whose byte size overflows uint32_t.
-  //
-  // Ideally we'd also try a large-but-ok capacity that almost but doesn't
-  // quite overflow, but that would result in allocating just under 4GB of
-  // entry storage.  That's very likely to fail on 32-bit platforms, so such a
-  // test wouldn't be reliable.
-
-  struct OneKBEntry {
-      PLDHashEntryHdr hdr;
-      char buf[1024 - sizeof(PLDHashEntryHdr)];
-  };
-
-  if (PL_DHashTableInit(&t, PL_DHashGetStubOps(), sizeof(OneKBEntry),
-                        mozilla::fallible, PL_DHASH_MAX_INITIAL_LENGTH)) {
-    return false;   // it succeeded!?
-  }
-  // Don't call PL_DHashTableFinish() here; it's not safe after Init() failure.
-
-  // Check that |ops| is still null.
-  if (t.IsInitialized()) {
-    return false;
-  }
-
-  return true;
-}
-
 static bool test_pldhash_lazy_storage()
 {
   PLDHashTable t;
@@ -226,8 +173,6 @@ static const struct Test {
   TestFunc    func;
 } tests[] = {
   DECL_TEST(test_pldhash_Init_capacity_ok),
-  DECL_TEST(test_pldhash_Init_capacity_too_large),
-  DECL_TEST(test_pldhash_Init_overflow),
   DECL_TEST(test_pldhash_lazy_storage),
 // See bug 931062, we skip this test on Android due to OOM.
 #ifndef MOZ_WIDGET_ANDROID