ICU-551.30.tar.gz

[apple/icu.git] / icuSources / layout / ScriptAndLanguage.cpp

diff --git a/icuSources/layout/ScriptAndLanguage.cpp b/icuSources/layout/ScriptAndLanguage.cpp
index 80941a5deec45d3d68d4cefaf0792fbfd2cbeadf..c7818d1866016fd8d6ec5a95ce3f0e540767b6dc 100644 (file)
--- a/icuSources/layout/ScriptAndLanguage.cpp
+++ b/icuSources/layout/ScriptAndLanguage.cpp
@@ -1,7 +1,5 @@
 /*
 /*

- * %W% %E%
- *
- * (C) Copyright IBM Corp. 1998-2003 - All Rights Reserved
+ * (C) Copyright IBM Corp. 1998-2013 - All Rights Reserved

  *
  */
 
  *
  */
 


@@ -13,49 +11,94 @@
 
 U_NAMESPACE_BEGIN
 
 
 U_NAMESPACE_BEGIN
 

-const LangSysTable *ScriptTable::findLanguage(LETag languageTag, le_bool exactMatch) const
+LEReferenceTo<LangSysTable> ScriptTable::findLanguage(const LETableReference& base, LETag languageTag, LEErrorCode &success, le_bool exactMatch) const

 {
     le_uint16 count = SWAPW(langSysCount);
     Offset langSysTableOffset = exactMatch? 0 : SWAPW(defaultLangSysTableOffset);
 
     if (count > 0) {
 {
     le_uint16 count = SWAPW(langSysCount);
     Offset langSysTableOffset = exactMatch? 0 : SWAPW(defaultLangSysTableOffset);
 
     if (count > 0) {

-        Offset foundOffset =
-            OpenTypeUtilities::getTagOffset(languageTag, langSysRecordArray, count);
-
-        if (foundOffset != 0) {
-            langSysTableOffset = foundOffset;
-        }
+      LEReferenceToArrayOf<TagAndOffsetRecord> langSysRecords(base, success, langSysRecordArray, count);
+      Offset foundOffset =
+        OpenTypeUtilities::getTagOffset(languageTag, langSysRecords, success);
+      
+      if (foundOffset != 0 && LE_SUCCESS(success)) {
+        langSysTableOffset = foundOffset;
+      }

     }
     }

-
+    

     if (langSysTableOffset != 0) {
     if (langSysTableOffset != 0) {

-        return (const LangSysTable *) ((char *)this + langSysTableOffset);
+      return LEReferenceTo<LangSysTable>(base, success, langSysTableOffset);

     }
 
     }
 

-    return 0;
+    return LEReferenceTo<LangSysTable>();

 }
 
 }
 

-const ScriptTable *ScriptListTable::findScript(LETag scriptTag) const
+LEReferenceTo<ScriptTable> ScriptListTable::findScript(const LETableReference &base, LETag scriptTag, LEErrorCode &success) const

 {
 {

+    if (LE_FAILURE(success) ) {
+      return LEReferenceTo<ScriptTable>(); // get out
+    }
+    /*
+     * There are some fonts that have a large, bogus value for scriptCount. To try
+     * and protect against this, we use the offset in the first scriptRecord,
+     * which we know has to be past the end of the scriptRecordArray, to compute
+     * a value which is greater than or equal to the actual script count.
+     *
+     * Note: normally, the first offset will point to just after the scriptRecordArray,
+     * but there's no guarantee of this, only that it's *after* the scriptRecordArray.
+     * Because of this, a binary serach isn't safe, because the new count may include
+     * data that's not actually in the scriptRecordArray and hence the array will appear
+     * to be unsorted.
+     */

     le_uint16 count = SWAPW(scriptCount);
     le_uint16 count = SWAPW(scriptCount);

-    Offset scriptTableOffset =
-        OpenTypeUtilities::getTagOffset(scriptTag, scriptRecordArray, count);
+
+    if (count == 0) {
+      return LEReferenceTo<ScriptTable>(); // no items, no search
+    }
+    
+    // attempt to construct a ref with at least one element
+    LEReferenceToArrayOf<ScriptRecord> oneElementTable(base, success, &scriptRecordArray[0], 1);
+    
+    if( LE_FAILURE(success) ) {
+      return LEReferenceTo<ScriptTable>(); // couldn't even read the first record - bad font.
+    }
+
+    le_uint16 limit = ((SWAPW(scriptRecordArray[0].offset) - sizeof(ScriptListTable)) / sizeof(scriptRecordArray)) + ANY_NUMBER;
+    Offset scriptTableOffset = 0;
+    
+
+    if (count > limit) {
+        // the scriptCount value is bogus; do a linear search
+        // because limit may still be too large.
+        LEReferenceToArrayOf<ScriptRecord> scriptRecordArrayRef(base, success, &scriptRecordArray[0], limit);
+        for(le_int32 s = 0; (s < limit)&&LE_SUCCESS(success); s += 1) {
+          if (SWAPT(scriptRecordArrayRef(s,success).tag) == scriptTag) {
+            scriptTableOffset = SWAPW(scriptRecordArrayRef(s,success).offset);
+            break;
+          }
+        }
+    } else {
+      LEReferenceToArrayOf<ScriptRecord> scriptRecordArrayRef(base, success, &scriptRecordArray[0], count);
+      
+      scriptTableOffset = OpenTypeUtilities::getTagOffset(scriptTag, scriptRecordArrayRef, success);
+    }

 
     if (scriptTableOffset != 0) {
 
     if (scriptTableOffset != 0) {

-        return (const ScriptTable *) ((char *)this + scriptTableOffset);
+      return LEReferenceTo<ScriptTable>(base, success, scriptTableOffset);

     }
 
     }
 

-    return 0;
+  return LEReferenceTo<ScriptTable>();

 }
 
 }
 

-const LangSysTable *ScriptListTable::findLanguage(LETag scriptTag, LETag languageTag, le_bool exactMatch) const
+LEReferenceTo<LangSysTable>  ScriptListTable::findLanguage(const LETableReference &base, LETag scriptTag, LETag languageTag, LEErrorCode &success, le_bool exactMatch) const 

 {
 {

-    const ScriptTable *scriptTable = findScript(scriptTag);
+  const LEReferenceTo<ScriptTable> scriptTable = findScript(base, scriptTag, success);

 
 

-    if (scriptTable == 0) {
-        return 0;
-    }
+  if (scriptTable.isEmpty()) {
+    return LEReferenceTo<LangSysTable>();
+  }

 
 

-    return scriptTable->findLanguage(languageTag, exactMatch);
+  return scriptTable->findLanguage(scriptTable, languageTag, success, exactMatch).reparent(base);

 }
 
 U_NAMESPACE_END
 }
 
 U_NAMESPACE_END