Moving sources copied from libantlr3c to separate file

3 files changed, 398 insertions, 4 deletions

diff --git a/src/parser/antlr_input.cpp b/src/parser/antlr_input.cpp
index 604502e50..b46e22853 100644
--- a/src/parser/antlr_input.cpp
+++ b/src/parser/antlr_input.cpp
@@ -134,7 +134,6 @@ void AntlrInput::setParser(pANTLR3_PARSER pParser) {
   // it would have to be declared separately in every input's grammar and we'd have to
   // pass it in as an address anyway.
   d_parser->super = getParserState();
-  d_parser->rec->match = &match;
   d_parser->rec->reportError = &reportError;
   d_parser->rec->recoverFromMismatchedToken = &recoverFromMismatchedToken;
 }
diff --git a/src/parser/antlr_input.h b/src/parser/antlr_input.h
index d77a2b586..c338c528a 100644
--- a/src/parser/antlr_input.h
+++ b/src/parser/antlr_input.h
@@ -64,9 +64,6 @@ class AntlrInput : public Input {
    *  NOTE: We assume that we <em>can</em> free it on exit. No sharing! */
   pANTLR3_INPUT_STREAM d_input;
 
-  static void *match(pANTLR3_BASE_RECOGNIZER recognizer, ANTLR3_UINT32 ttype,
-                     pANTLR3_BITSET_LIST follow);
-
   /** Turns an ANTLR3 exception into a message for the user and calls <code>parseError</code>. */
   static void reportError(pANTLR3_BASE_RECOGNIZER recognizer);
 
diff --git a/src/parser/antlr_input_imports.cpp b/src/parser/antlr_input_imports.cpp
new file mode 100644
index 000000000..3476507ab
--- /dev/null
+++ b/src/parser/antlr_input_imports.cpp
@@ -0,0 +1,398 @@
+/*
+ * The functions in this file are based on implementations in libantlr3c,
+ * with only minor CVC4-specific changes.
+ */
+
+// [The "BSD licence"]
+// Copyright (c) 2005-2009 Jim Idle, Temporal Wave LLC
+// http://www.temporal-wave.com
+// http://www.linkedin.com/in/jimidle
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+// 3. The name of the author may not be used to endorse or promote products
+//    derived from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+// IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <antlr3.h>
+#include <sstream>
+
+#include "antlr_input.h"
+#include "parser_state.h"
+#include "util/Assert.h"
+
+using namespace std;
+
+namespace CVC4 {
+namespace parser {
+
+/// Match current input symbol against ttype.  Upon error, do one token
+/// insertion or deletion if possible.
+/// To turn off single token insertion or deletion error
+/// recovery, override mismatchRecover() and have it call
+/// plain mismatch(), which does not recover.  Then any error
+/// in a rule will cause an exception and immediate exit from
+/// rule.  Rule would recover by resynchronizing to the set of
+/// symbols that can follow rule ref.
+///
+/* *** CVC4 NOTE ***
+ * This function is unchanged from its libantlr3c version. It is included
+ * here to avoid an exception-handling bug caused by libantlr3c being compiled
+ * without support for C++ exceptions by default.
+ */
+void *
+AntlrInput::match(pANTLR3_BASE_RECOGNIZER recognizer, ANTLR3_UINT32 ttype,
+      pANTLR3_BITSET_LIST follow) {
+  pANTLR3_PARSER parser;
+  pANTLR3_TREE_PARSER tparser;
+  pANTLR3_INT_STREAM is;
+  void * matchedSymbol;
+
+  switch(recognizer->type) {
+  case ANTLR3_TYPE_PARSER:
+
+    parser = (pANTLR3_PARSER)(recognizer->super);
+    tparser = NULL;
+    is = parser->tstream->istream;
+
+    break;
+
+  case ANTLR3_TYPE_TREE_PARSER:
+
+    tparser = (pANTLR3_TREE_PARSER)(recognizer->super);
+    parser = NULL;
+    is = tparser->ctnstream->tnstream->istream;
+
+    break;
+
+  default:
+
+    ANTLR3_FPRINTF(
+                   stderr,
+                   "Base recognizer function 'match' called by unknown parser type - provide override for this function\n");
+    return ANTLR3_FALSE;
+
+    break;
+  }
+
+  // Pick up the current input token/node for assignment to labels
+  //
+  matchedSymbol = recognizer->getCurrentInputSymbol(recognizer, is);
+
+  if(is->_LA(is, 1) == ttype) {
+    // The token was the one we were told to expect
+    //
+    is->consume(is); // Consume that token from the stream
+    recognizer->state->errorRecovery = ANTLR3_FALSE; // Not in error recovery now (if we were)
+    recognizer->state->failed = ANTLR3_FALSE; // The match was a success
+    return matchedSymbol; // We are done
+  }
+
+  // We did not find the expected token type, if we are backtracking then
+  // we just set the failed flag and return.
+  //
+  if(recognizer->state->backtracking > 0) {
+    // Backtracking is going on
+    //
+    recognizer->state->failed = ANTLR3_TRUE;
+    return matchedSymbol;
+  }
+
+  // We did not find the expected token and there is no backtracking
+  // going on, so we mismatch, which creates an exception in the recognizer exception
+  // stack.
+  //
+  matchedSymbol = recognizer->recoverFromMismatchedToken(recognizer, ttype,
+                                                         follow);
+  return matchedSymbol;
+}
+
+/// Attempt to recover from a single missing or extra token.
+///
+/// EXTRA TOKEN
+///
+/// LA(1) is not what we are looking for.  If LA(2) has the right token,
+/// however, then assume LA(1) is some extra spurious token.  Delete it
+/// and LA(2) as if we were doing a normal match(), which advances the
+/// input.
+///
+/// MISSING TOKEN
+///
+/// If current token is consistent with what could come after
+/// ttype then it is ok to "insert" the missing token, else throw
+/// exception For example, Input "i=(3;" is clearly missing the
+/// ')'.  When the parser returns from the nested call to expr, it
+/// will have call chain:
+///
+///    stat -> expr -> atom
+///
+/// and it will be trying to match the ')' at this point in the
+/// derivation:
+///
+///       => ID '=' '(' INT ')' ('+' atom)* ';'
+///                          ^
+/// match() will see that ';' doesn't match ')' and report a
+/// mismatched token error.  To recover, it sees that LA(1)==';'
+/// is in the set of tokens that can follow the ')' token
+/// reference in rule atom.  It can assume that you forgot the ')'.
+///
+/// The exception that was passed in, in the java implementation is
+/// sorted in the recognizer exception stack in the C version. To 'throw' it we set the
+/// error flag and rules cascade back when this is set.
+///
+/* *** CVC4 NOTE ***
+ * This function has been basically gutted to remove any attempts to recover
+ * from a syntax error.
+ */
+void *
+AntlrInput::recoverFromMismatchedToken(pANTLR3_BASE_RECOGNIZER recognizer,
+                                       ANTLR3_UINT32 ttype,
+                                       pANTLR3_BITSET_LIST follow) {
+
+  pANTLR3_PARSER parser = (pANTLR3_PARSER) (recognizer->super);
+  pANTLR3_INT_STREAM is = parser->tstream->istream;
+  void *matchedSymbol;
+
+
+  // Create an exception if we need one
+  //
+  if(recognizer->state->exception == NULL) {
+    antlr3RecognitionExceptionNew(recognizer);
+  }
+
+  if(recognizer->mismatchIsUnwantedToken(recognizer, is, ttype) == ANTLR3_TRUE) {
+    recognizer->state->exception->type = ANTLR3_UNWANTED_TOKEN_EXCEPTION;
+    recognizer->state->exception->message
+        = (void*)ANTLR3_UNWANTED_TOKEN_EXCEPTION_NAME;
+  }
+
+  if(recognizer->mismatchIsMissingToken(recognizer, is, follow)) {
+    matchedSymbol = recognizer->getMissingSymbol(recognizer, is,
+                                                 recognizer->state->exception,
+                                                 ttype, follow);
+    recognizer->state->exception->type = ANTLR3_MISSING_TOKEN_EXCEPTION;
+    recognizer->state->exception->message = (void*)ANTLR3_MISSING_TOKEN_EXCEPTION_NAME;
+    recognizer->state->exception->token = matchedSymbol;
+    recognizer->state->exception->expecting = ttype;
+  }
+
+  reportError(recognizer);
+  Unreachable("reportError should have thrown exception in AntlrInput::recoverFromMismatchedToken");
+}
+
+
+/// Report a recognition problem.
+///
+/// This method sets errorRecovery to indicate the parser is recovering
+/// not parsing.  Once in recovery mode, no errors are generated.
+/// To get out of recovery mode, the parser must successfully match
+/// a token (after a resync).  So it will go:
+///
+///             1. error occurs
+///             2. enter recovery mode, report error
+///             3. consume until token found in resynch set
+///             4. try to resume parsing
+///             5. next match() will reset errorRecovery mode
+///
+/// If you override, make sure to update errorCount if you care about that.
+///
+/* *** CVC4 NOTE ***
+ * This function is has been modified in not-completely-trivial ways from its
+ * libantlr3c implementation to support more informative error messages and to
+ * invoke the error reporting mechanism of the AntlrInput class instead of the
+ * default error printer.
+ */
+void AntlrInput::reportError(pANTLR3_BASE_RECOGNIZER recognizer) {
+  pANTLR3_EXCEPTION ex = recognizer->state->exception;
+  pANTLR3_UINT8 * tokenNames = recognizer->state->tokenNames;
+  stringstream ss;
+
+  // Signal we are in error recovery now
+  recognizer->state->errorRecovery = ANTLR3_TRUE;
+
+  // Indicate this recognizer had an error while processing.
+  recognizer->state->errorCount++;
+
+  // Call the builtin error formatter
+  // recognizer->displayRecognitionError(recognizer, recognizer->state->tokenNames);
+
+  /* TODO: Make error messages more useful, maybe by including more expected tokens and information
+   * about the current token. */
+  switch(ex->type) {
+  case ANTLR3_UNWANTED_TOKEN_EXCEPTION:
+
+    // Indicates that the recognizer was fed a token which seems to be
+    // spurious input. We can detect this when the token that follows
+    // this unwanted token would normally be part of the syntactically
+    // correct stream. Then we can see that the token we are looking at
+    // is just something that should not be there and throw this exception.
+    //
+    if(tokenNames == NULL) {
+      ss << "Unexpected token." ;
+    } else {
+      if(ex->expecting == ANTLR3_TOKEN_EOF) {
+        ss << "Expected end of file.";
+      } else {
+        ss << "Expected " << tokenNames[ex->expecting]
+           << ", found '" << tokenText((pANTLR3_COMMON_TOKEN)ex->token) << "'.";
+      }
+    }
+    break;
+
+  case ANTLR3_MISSING_TOKEN_EXCEPTION:
+
+    // Indicates that the recognizer detected that the token we just
+    // hit would be valid syntactically if preceded by a particular
+    // token. Perhaps a missing ';' at line end or a missing ',' in an
+    // expression list, and such like.
+    //
+    if(tokenNames == NULL) {
+      ss << "Missing token (" << ex->expecting << ").";
+    } else {
+      if(ex->expecting == ANTLR3_TOKEN_EOF) {
+        ss << "Missing end of file marker.";
+      } else {
+        ss << "Missing " << tokenNames[ex->expecting] << ".";
+      }
+    }
+    break;
+
+  case ANTLR3_RECOGNITION_EXCEPTION:
+
+    // Indicates that the recognizer received a token
+    // in the input that was not predicted. This is the basic exception type
+    // from which all others are derived. So we assume it was a syntax error.
+    // You may get this if there are not more tokens and more are needed
+    // to complete a parse for instance.
+    //
+    ss <<"Syntax error.";
+    break;
+
+  case ANTLR3_MISMATCHED_TOKEN_EXCEPTION:
+
+    // We were expecting to see one thing and got another. This is the
+    // most common error if we could not detect a missing or unwanted token.
+    // Here you can spend your efforts to
+    // derive more useful error messages based on the expected
+    // token set and the last token and so on. The error following
+    // bitmaps do a good job of reducing the set that we were looking
+    // for down to something small. Knowing what you are parsing may be
+    // able to allow you to be even more specific about an error.
+    //
+    if(tokenNames == NULL) {
+      ss << "Syntax error.";
+    } else {
+      if(ex->expecting == ANTLR3_TOKEN_EOF) {
+        ss << "Expected end of file.";
+      } else {
+        ss << "Expected " << tokenNames[ex->expecting] << ".";
+      }
+    }
+    break;
+
+  case ANTLR3_NO_VIABLE_ALT_EXCEPTION:
+    // We could not pick any alt decision from the input given
+    // so god knows what happened - however when you examine your grammar,
+    // you should. It means that at the point where the current token occurred
+    // that the DFA indicates nowhere to go from here.
+    //
+    ss << "Unexpected token: '" << tokenText((pANTLR3_COMMON_TOKEN)ex->token) << "'.";
+    break;
+
+  case ANTLR3_MISMATCHED_SET_EXCEPTION:
+
+  {
+    ANTLR3_UINT32 count;
+    ANTLR3_UINT32 bit;
+    ANTLR3_UINT32 size;
+    ANTLR3_UINT32 numbits;
+    pANTLR3_BITSET errBits;
+
+    // This means we were able to deal with one of a set of
+    // possible tokens at this point, but we did not see any
+    // member of that set.
+    //
+    ss << "Unexpected input: '" << tokenText((pANTLR3_COMMON_TOKEN)ex->token)
+       << "'. Expected one of: ";
+
+    // What tokens could we have accepted at this point in the
+    // parse?
+    //
+    count = 0;
+    errBits = antlr3BitsetLoad(ex->expectingSet);
+    numbits = errBits->numBits(errBits);
+    size = errBits->size(errBits);
+
+    if(size > 0) {
+      // However many tokens we could have dealt with here, it is usually
+      // not useful to print ALL of the set here. I arbitrarily chose 8
+      // here, but you should do whatever makes sense for you of course.
+      // No token number 0, so look for bit 1 and on.
+      //
+      for(bit = 1; bit < numbits && count < 8 && count < size; bit++) {
+        // TODO: This doesn;t look right - should be asking if the bit is set!!
+        //
+        if(tokenNames[bit]) {
+          if( count++ > 0 ) {
+            ss << ", ";
+          }
+          ss << tokenNames[bit];
+        }
+      }
+    } else {
+      Unreachable("Parse error with empty set of expected tokens.");
+    }
+  }
+    break;
+
+  case ANTLR3_EARLY_EXIT_EXCEPTION:
+
+    // We entered a loop requiring a number of token sequences
+    // but found a token that ended that sequence earlier than
+    // we should have done.
+    //
+    ss << "Sequence terminated early by token: '"
+       << tokenText((pANTLR3_COMMON_TOKEN)ex->token) << "'.";
+    break;
+
+  default:
+
+    // We don't handle any other exceptions here, but you can
+    // if you wish. If we get an exception that hits this point
+    // then we are just going to report what we know about the
+    // token.
+    //
+    Unhandled("Unexpected exception in parser.");
+    break;
+  }
+
+  // Now get ready to throw an exception
+  pANTLR3_PARSER parser = (pANTLR3_PARSER)(recognizer->super);
+  AlwaysAssert(parser!=NULL);
+  ParserState *parserState = (ParserState*)(parser->super);
+  AlwaysAssert(parserState!=NULL);
+
+  // Call the error display routine
+  parserState->parseError(ss.str());
+}
+
+} // namespace parser
+} // namespace CVC4