1 files changed, 428 insertions, 0 deletions
diff --git a/layout/mathml/nsMathMLOperators.cpp b/layout/mathml/nsMathMLOperators.cpp
new file mode 100644
index 0000000000..fbfe686e32
--- /dev/null
+++ b/layout/mathml/nsMathMLOperators.cpp
@@ -0,0 +1,428 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMathMLOperators.h"
+#include "nsCOMPtr.h"
+#include "nsDataHashtable.h"
+#include "nsHashKeys.h"
+#include "nsNetUtil.h"
+#include "nsTArray.h"
+
+#include "nsIPersistentProperties2.h"
+#include "nsISimpleEnumerator.h"
+#include "nsCRT.h"
+
+// operator dictionary entry
+struct OperatorData {
+  OperatorData(void) : mFlags(0), mLeadingSpace(0.0f), mTrailingSpace(0.0f) {}
+
+  // member data
+  nsString mStr;
+  nsOperatorFlags mFlags;
+  float mLeadingSpace;   // unit is em
+  float mTrailingSpace;  // unit is em
+};
+
+static int32_t gTableRefCount = 0;
+static uint32_t gOperatorCount = 0;
+static OperatorData* gOperatorArray = nullptr;
+static nsDataHashtable<nsStringHashKey, OperatorData*>* gOperatorTable =
+    nullptr;
+static bool gGlobalsInitialized = false;
+
+static const char16_t kDashCh = char16_t('#');
+static const char16_t kColonCh = char16_t(':');
+
+static void SetBooleanProperty(OperatorData* aOperatorData, nsString aName) {
+  if (aName.IsEmpty()) return;
+
+  if (aName.EqualsLiteral("stretchy") && (1 == aOperatorData->mStr.Length()))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_STRETCHY;
+  else if (aName.EqualsLiteral("fence"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_FENCE;
+  else if (aName.EqualsLiteral("accent"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_ACCENT;
+  else if (aName.EqualsLiteral("largeop"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_LARGEOP;
+  else if (aName.EqualsLiteral("separator"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_SEPARATOR;
+  else if (aName.EqualsLiteral("movablelimits"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_MOVABLELIMITS;
+  else if (aName.EqualsLiteral("symmetric"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_SYMMETRIC;
+  else if (aName.EqualsLiteral("integral"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_INTEGRAL;
+  else if (aName.EqualsLiteral("mirrorable"))
+    aOperatorData->mFlags |= NS_MATHML_OPERATOR_MIRRORABLE;
+}
+
+static void SetProperty(OperatorData* aOperatorData, nsString aName,
+                        nsString aValue) {
+  if (aName.IsEmpty() || aValue.IsEmpty()) return;
+
+  // XXX These ones are not kept in the dictionary
+  // Support for these requires nsString member variables
+  // maxsize (default: infinity)
+  // minsize (default: 1)
+
+  if (aName.EqualsLiteral("direction")) {
+    if (aValue.EqualsLiteral("vertical"))
+      aOperatorData->mFlags |= NS_MATHML_OPERATOR_DIRECTION_VERTICAL;
+    else if (aValue.EqualsLiteral("horizontal"))
+      aOperatorData->mFlags |= NS_MATHML_OPERATOR_DIRECTION_HORIZONTAL;
+    else
+      return;  // invalid value
+  } else {
+    bool isLeadingSpace;
+    if (aName.EqualsLiteral("lspace"))
+      isLeadingSpace = true;
+    else if (aName.EqualsLiteral("rspace"))
+      isLeadingSpace = false;
+    else
+      return;  // input is not applicable
+
+    // aValue is assumed to be a digit from 0 to 7
+    nsresult error = NS_OK;
+    float space = aValue.ToFloat(&error) / 18.0;
+    if (NS_FAILED(error)) return;
+
+    if (isLeadingSpace)
+      aOperatorData->mLeadingSpace = space;
+    else
+      aOperatorData->mTrailingSpace = space;
+  }
+}
+
+static bool SetOperator(OperatorData* aOperatorData, nsOperatorFlags aForm,
+                        const nsCString& aOperator, nsString& aAttributes)
+
+{
+  static const char16_t kNullCh = char16_t('\0');
+
+  // aOperator is in the expanded format \uNNNN\uNNNN ...
+  // First compress these Unicode points to the internal nsString format
+  int32_t i = 0;
+  nsAutoString name, value;
+  int32_t len = aOperator.Length();
+  char16_t c = aOperator[i++];
+  uint32_t state = 0;
+  char16_t uchar = 0;
+  while (i <= len) {
+    if (0 == state) {
+      if (c != '\\') return false;
+      if (i < len) c = aOperator[i];
+      i++;
+      if (('u' != c) && ('U' != c)) return false;
+      if (i < len) c = aOperator[i];
+      i++;
+      state++;
+    } else {
+      if (('0' <= c) && (c <= '9'))
+        uchar = (uchar << 4) | (c - '0');
+      else if (('a' <= c) && (c <= 'f'))
+        uchar = (uchar << 4) | (c - 'a' + 0x0a);
+      else if (('A' <= c) && (c <= 'F'))
+        uchar = (uchar << 4) | (c - 'A' + 0x0a);
+      else
+        return false;
+      if (i < len) c = aOperator[i];
+      i++;
+      state++;
+      if (5 == state) {
+        value.Append(uchar);
+        uchar = 0;
+        state = 0;
+      }
+    }
+  }
+  if (0 != state) return false;
+
+  // Quick return when the caller doesn't care about the attributes and just
+  // wants to know if this is a valid operator (this is the case at the first
+  // pass of the parsing of the dictionary in InitOperators())
+  if (!aForm) return true;
+
+  // Add operator to hash table
+  aOperatorData->mFlags |= aForm;
+  aOperatorData->mStr.Assign(value);
+  value.AppendInt(aForm, 10);
+  gOperatorTable->Put(value, aOperatorData);
+
+#ifdef DEBUG
+  NS_LossyConvertUTF16toASCII str(aAttributes);
+#endif
+  // Loop over the space-delimited list of attributes to get the name:value
+  // pairs
+  aAttributes.Append(kNullCh);  // put an extra null at the end
+  char16_t* start = aAttributes.BeginWriting();
+  char16_t* end = start;
+  while ((kNullCh != *start) && (kDashCh != *start)) {
+    name.SetLength(0);
+    value.SetLength(0);
+    // skip leading space, the dash amounts to the end of the line
+    while ((kNullCh != *start) && (kDashCh != *start) &&
+           nsCRT::IsAsciiSpace(*start)) {
+      ++start;
+    }
+    end = start;
+    // look for ':'
+    while ((kNullCh != *end) && (kDashCh != *end) &&
+           !nsCRT::IsAsciiSpace(*end) && (kColonCh != *end)) {
+      ++end;
+    }
+    // If ':' is not found, then it's a boolean property
+    bool IsBooleanProperty = (kColonCh != *end);
+    *end = kNullCh;  // end segment here
+    // this segment is the name
+    if (start < end) {
+      name.Assign(start);
+    }
+    if (IsBooleanProperty) {
+      SetBooleanProperty(aOperatorData, name);
+    } else {
+      start = ++end;
+      // look for space or end of line
+      while ((kNullCh != *end) && (kDashCh != *end) &&
+             !nsCRT::IsAsciiSpace(*end)) {
+        ++end;
+      }
+      *end = kNullCh;  // end segment here
+      if (start < end) {
+        // this segment is the value
+        value.Assign(start);
+      }
+      SetProperty(aOperatorData, name, value);
+    }
+    start = ++end;
+  }
+  return true;
+}
+
+static nsresult InitOperators(void) {
+  // Load the property file containing the Operator Dictionary
+  nsresult rv;
+  nsCOMPtr<nsIPersistentProperties> mathfontProp;
+  rv = NS_LoadPersistentPropertiesFromURISpec(
+      getter_AddRefs(mathfontProp),
+      "resource://gre/res/fonts/mathfont.properties"_ns);
+
+  if (NS_FAILED(rv)) return rv;
+
+  // Parse the Operator Dictionary in two passes.
+  // The first pass is to count the number of operators; the second pass is to
+  // allocate the necessary space for them and to add them in the hash table.
+  for (int32_t pass = 1; pass <= 2; pass++) {
+    OperatorData dummyData;
+    OperatorData* operatorData = &dummyData;
+    nsCOMPtr<nsISimpleEnumerator> iterator;
+    if (NS_SUCCEEDED(mathfontProp->Enumerate(getter_AddRefs(iterator)))) {
+      bool more;
+      uint32_t index = 0;
+      nsAutoCString name;
+      nsAutoString attributes;
+      while ((NS_SUCCEEDED(iterator->HasMoreElements(&more))) && more) {
+        nsCOMPtr<nsISupports> supports;
+        nsCOMPtr<nsIPropertyElement> element;
+        if (NS_SUCCEEDED(iterator->GetNext(getter_AddRefs(supports)))) {
+          element = do_QueryInterface(supports);
+          if (NS_SUCCEEDED(element->GetKey(name)) &&
+              NS_SUCCEEDED(element->GetValue(attributes))) {
+            // expected key: operator.\uNNNN.{infix,postfix,prefix}
+            if ((21 <= name.Length()) && (0 == name.Find("operator.\\u"))) {
+              name.Cut(0, 9);  // 9 is the length of "operator.";
+              int32_t len = name.Length();
+              nsOperatorFlags form = 0;
+              if (kNotFound != name.RFind(".infix")) {
+                form = NS_MATHML_OPERATOR_FORM_INFIX;
+                len -= 6;  // 6 is the length of ".infix";
+              } else if (kNotFound != name.RFind(".postfix")) {
+                form = NS_MATHML_OPERATOR_FORM_POSTFIX;
+                len -= 8;  // 8 is the length of ".postfix";
+              } else if (kNotFound != name.RFind(".prefix")) {
+                form = NS_MATHML_OPERATOR_FORM_PREFIX;
+                len -= 7;  // 7 is the length of ".prefix";
+              } else
+                continue;  // input is not applicable
+              name.SetLength(len);
+              if (2 == pass) {  // allocate space and start the storage
+                if (!gOperatorArray) {
+                  if (0 == gOperatorCount) return NS_ERROR_UNEXPECTED;
+                  gOperatorArray = new OperatorData[gOperatorCount];
+                  if (!gOperatorArray) return NS_ERROR_OUT_OF_MEMORY;
+                }
+                operatorData = &gOperatorArray[index];
+              } else {
+                form = 0;  // to quickly return from SetOperator() at pass 1
+              }
+              // See if the operator should be retained
+              if (SetOperator(operatorData, form, name, attributes)) {
+                index++;
+                if (1 == pass) gOperatorCount = index;
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  return NS_OK;
+}
+
+static nsresult InitOperatorGlobals() {
+  gGlobalsInitialized = true;
+  nsresult rv = NS_ERROR_OUT_OF_MEMORY;
+  gOperatorTable = new nsDataHashtable<nsStringHashKey, OperatorData*>();
+  if (gOperatorTable) {
+    rv = InitOperators();
+  }
+  if (NS_FAILED(rv)) nsMathMLOperators::CleanUp();
+  return rv;
+}
+
+void nsMathMLOperators::CleanUp() {
+  if (gOperatorArray) {
+    delete[] gOperatorArray;
+    gOperatorArray = nullptr;
+  }
+  if (gOperatorTable) {
+    delete gOperatorTable;
+    gOperatorTable = nullptr;
+  }
+}
+
+void nsMathMLOperators::AddRefTable(void) { gTableRefCount++; }
+
+void nsMathMLOperators::ReleaseTable(void) {
+  if (0 == --gTableRefCount) {
+    CleanUp();
+  }
+}
+
+static OperatorData* GetOperatorData(const nsString& aOperator,
+                                     nsOperatorFlags aForm) {
+  nsAutoString key(aOperator);
+  key.AppendInt(aForm);
+  return gOperatorTable->Get(key);
+}
+
+bool nsMathMLOperators::LookupOperator(const nsString& aOperator,
+                                       const nsOperatorFlags aForm,
+                                       nsOperatorFlags* aFlags,
+                                       float* aLeadingSpace,
+                                       float* aTrailingSpace) {
+  if (!gGlobalsInitialized) {
+    InitOperatorGlobals();
+  }
+  if (gOperatorTable) {
+    NS_ASSERTION(aFlags && aLeadingSpace && aTrailingSpace, "bad usage");
+    NS_ASSERTION(aForm > 0 && aForm < 4, "*** invalid call ***");
+
+    // The MathML REC says:
+    // If the operator does not occur in the dictionary with the specified form,
+    // the renderer should use one of the forms which is available there, in the
+    // order of preference: infix, postfix, prefix.
+
+    OperatorData* found;
+    int32_t form = NS_MATHML_OPERATOR_GET_FORM(aForm);
+    if (!(found = GetOperatorData(aOperator, form))) {
+      if (form == NS_MATHML_OPERATOR_FORM_INFIX ||
+          !(found =
+                GetOperatorData(aOperator, NS_MATHML_OPERATOR_FORM_INFIX))) {
+        if (form == NS_MATHML_OPERATOR_FORM_POSTFIX ||
+            !(found = GetOperatorData(aOperator,
+                                      NS_MATHML_OPERATOR_FORM_POSTFIX))) {
+          if (form != NS_MATHML_OPERATOR_FORM_PREFIX) {
+            found = GetOperatorData(aOperator, NS_MATHML_OPERATOR_FORM_PREFIX);
+          }
+        }
+      }
+    }
+    if (found) {
+      NS_ASSERTION(found->mStr.Equals(aOperator), "bad setup");
+      *aLeadingSpace = found->mLeadingSpace;
+      *aTrailingSpace = found->mTrailingSpace;
+      *aFlags &= ~NS_MATHML_OPERATOR_FORM;  // clear the form bits
+      *aFlags |= found->mFlags;             // just add bits without overwriting
+      return true;
+    }
+  }
+  return false;
+}
+
+void nsMathMLOperators::LookupOperators(const nsString& aOperator,
+                                        nsOperatorFlags* aFlags,
+                                        float* aLeadingSpace,
+                                        float* aTrailingSpace) {
+  if (!gGlobalsInitialized) {
+    InitOperatorGlobals();
+  }
+
+  aFlags[NS_MATHML_OPERATOR_FORM_INFIX] = 0;
+  aLeadingSpace[NS_MATHML_OPERATOR_FORM_INFIX] = 0.0f;
+  aTrailingSpace[NS_MATHML_OPERATOR_FORM_INFIX] = 0.0f;
+
+  aFlags[NS_MATHML_OPERATOR_FORM_POSTFIX] = 0;
+  aLeadingSpace[NS_MATHML_OPERATOR_FORM_POSTFIX] = 0.0f;
+  aTrailingSpace[NS_MATHML_OPERATOR_FORM_POSTFIX] = 0.0f;
+
+  aFlags[NS_MATHML_OPERATOR_FORM_PREFIX] = 0;
+  aLeadingSpace[NS_MATHML_OPERATOR_FORM_PREFIX] = 0.0f;
+  aTrailingSpace[NS_MATHML_OPERATOR_FORM_PREFIX] = 0.0f;
+
+  if (gOperatorTable) {
+    OperatorData* found;
+    found = GetOperatorData(aOperator, NS_MATHML_OPERATOR_FORM_INFIX);
+    if (found) {
+      aFlags[NS_MATHML_OPERATOR_FORM_INFIX] = found->mFlags;
+      aLeadingSpace[NS_MATHML_OPERATOR_FORM_INFIX] = found->mLeadingSpace;
+      aTrailingSpace[NS_MATHML_OPERATOR_FORM_INFIX] = found->mTrailingSpace;
+    }
+    found = GetOperatorData(aOperator, NS_MATHML_OPERATOR_FORM_POSTFIX);
+    if (found) {
+      aFlags[NS_MATHML_OPERATOR_FORM_POSTFIX] = found->mFlags;
+      aLeadingSpace[NS_MATHML_OPERATOR_FORM_POSTFIX] = found->mLeadingSpace;
+      aTrailingSpace[NS_MATHML_OPERATOR_FORM_POSTFIX] = found->mTrailingSpace;
+    }
+    found = GetOperatorData(aOperator, NS_MATHML_OPERATOR_FORM_PREFIX);
+    if (found) {
+      aFlags[NS_MATHML_OPERATOR_FORM_PREFIX] = found->mFlags;
+      aLeadingSpace[NS_MATHML_OPERATOR_FORM_PREFIX] = found->mLeadingSpace;
+      aTrailingSpace[NS_MATHML_OPERATOR_FORM_PREFIX] = found->mTrailingSpace;
+    }
+  }
+}
+
+/* static */
+bool nsMathMLOperators::IsMirrorableOperator(const nsString& aOperator) {
+  // LookupOperator will search infix, postfix and prefix forms of aOperator and
+  // return the first form found. It is assumed that all these forms have same
+  // mirrorability.
+  nsOperatorFlags flags = 0;
+  float dummy;
+  nsMathMLOperators::LookupOperator(aOperator, NS_MATHML_OPERATOR_FORM_INFIX,
+                                    &flags, &dummy, &dummy);
+  return NS_MATHML_OPERATOR_IS_MIRRORABLE(flags);
+}
+
+/* static */
+nsStretchDirection nsMathMLOperators::GetStretchyDirection(
+    const nsString& aOperator) {
+  // LookupOperator will search infix, postfix and prefix forms of aOperator and
+  // return the first form found. It is assumed that all these forms have same
+  // direction.
+  nsOperatorFlags flags = 0;
+  float dummy;
+  nsMathMLOperators::LookupOperator(aOperator, NS_MATHML_OPERATOR_FORM_INFIX,
+                                    &flags, &dummy, &dummy);
+
+  if (NS_MATHML_OPERATOR_IS_DIRECTION_VERTICAL(flags)) {
+    return NS_STRETCH_DIRECTION_VERTICAL;
+  } else if (NS_MATHML_OPERATOR_IS_DIRECTION_HORIZONTAL(flags)) {
+    return NS_STRETCH_DIRECTION_HORIZONTAL;
+  } else {
+    return NS_STRETCH_DIRECTION_UNSUPPORTED;
+  }
+}