lou_backTranslateString.c fix

This commit fixes back translation problems when words gets split in
unusual places causeing back translation of whole words for example K5
back translates to Knowledgeen, M>k back translates to Moreark, and M5
back translates to Moren.  This caused over 8400 extra back
translation problems.

NEWS

@@ -5,6 +5,11 @@ liblouis NEWS -- history of user-visible changes.  	-*- org -*-
 - Added a callback system for logging purposes.
 
 ** Bug fixes
+- fix back translation problems when word gets split in unusual places
+causeing back translation of whole words for example K5 back
+translates to Knowledgeen, M>k back translates to Moreark, and M5 back
+translates to Moren.  This caused over 8400 extra back translation errors in en-us-g2 and 5000 in en-ueb-g2..
+
 - Fixed bug to prevent removal of \xffff between largesign rules. This
   solves a LibLouisUTDML bug where \xffff is used as a segment delimiter.
 - Fixed a bug in backtranslation, when a letsign was encountered, the

liblouis/lou_backTranslateString.c

@@ -416,27 +416,37 @@ static int
 isEndWord ()
 {
 /*See if this is really the end of a word. */
-  int k = src + currentDotslen;
-  TranslationTableOffset ruleOffset;
-  unsigned long int makeHash;
-  const TranslationTableCharacter *dots =
-    back_findCharOrDots (currentInput[k], 1);
-  if (k >= srcmax)
-    return 1;
-  if (dots->attributes & CTC_Space)
-    return 1;
-  if (dots->attributes & CTC_Letter)
-    return 0;
-  makeHash = (unsigned long int) dots->lowercase << 8;
-  makeHash += (unsigned long int) (back_findCharOrDots
-				   (currentInput[k + 1], 1))->lowercase;
-  makeHash %= HASHNUM;
-  ruleOffset = table->backRules[makeHash];
-  if (ruleOffset != 0)
-    return 0;
+  int k;
+  const TranslationTableCharacter *dots;
+  TranslationTableOffset testRuleOffset;
+  TranslationTableRule *testRule;
+  for (k = src + currentDotslen; k < srcmax; k++)
+    {
+      int postpuncFound = 0;
+      int TranslationFound = 0;
+      dots = back_findCharOrDots (currentInput[k], 1);
+      testRuleOffset = dots->otherRules;
+      if (dots->attributes & CTC_Space)
+	break;
+      if (dots->attributes & CTC_Letter)
+	return 0;
+      while (testRuleOffset)
+	{
+	  testRule =
+	    (TranslationTableRule *) & table->ruleArea[testRuleOffset];
+	  if (testRule->charslen > 1)
+	    TranslationFound = 1;
+	  if (testRule->opcode == CTO_PostPunc)
+	    postpuncFound = 1;
+	  if (testRule->opcode == CTO_Hyphen)
+	    return 1;
+	  testRuleOffset = testRule->dotsnext;
+	}
+      if (TranslationFound && !postpuncFound)
+	return 0;
+    }
   return 1;
 }
-
 static int
 findBrailleIndicatorRule (TranslationTableOffset offset)
 {