Issue #303 Part 1: Move basilisk files from /browser to /application/basilisk

1 files changed, 569 insertions, 0 deletions

diff --git a/application/basilisk/components/translation/cld2/internal/offsetmap.cc b/application/basilisk/components/translation/cld2/internal/offsetmap.cc
new file mode 100644
index 000000000..84609a71f
--- /dev/null
+++ b/application/basilisk/components/translation/cld2/internal/offsetmap.cc
@@ -0,0 +1,569 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//
+// Author: dsites@google.com (Dick Sites)
+//
+//
+
+#include "offsetmap.h"
+
+#include <string.h>                     // for strcmp
+#include <stdio.h>                      // for fprintf, stderr, fclose, etc
+#include <algorithm>                    // for min
+
+using namespace std;
+
+namespace CLD2 {
+
+// Constructor, destructor
+OffsetMap::OffsetMap() {
+  Clear();
+}
+
+OffsetMap::~OffsetMap() {
+}
+
+// Clear the map
+// After:
+//   next_diff_sub_ is 0
+//   Windows are the a and a' ranges covered by diffs_[next_diff_sub_-1]
+//   which is a fake range of width 0 mapping 0=>0
+void OffsetMap::Clear() {
+  diffs_.clear();
+  pending_op_ = COPY_OP;
+  pending_length_ = 0;
+  next_diff_sub_ = 0;
+  current_lo_aoffset_ = 0;
+  current_hi_aoffset_ = 0;
+  current_lo_aprimeoffset_ = 0;
+  current_hi_aprimeoffset_ = 0;
+  current_diff_ = 0;
+  max_aoffset_ = 0;           // Largest seen so far
+  max_aprimeoffset_ = 0;      // Largest seen so far
+}
+
+static inline char OpPart(const char c) {
+  return (c >> 6) & 3;
+}
+static inline char LenPart(const char c) {
+  return c & 0x3f;
+}
+
+// Print map to file, for debugging
+void OffsetMap::Printmap(const char* filename) {
+  FILE* fout;
+  bool needs_close = false;
+  if (strcmp(filename, "stdout") == 0) {
+    fout = stdout;
+  } else if (strcmp(filename, "stderr") == 0) {
+    fout = stderr;
+  } else {
+    fout = fopen(filename, "w");
+    needs_close = true;
+  }
+  if (fout == NULL) {
+    fprintf(stderr, "%s did not open\n", filename);
+    return;
+  }
+
+  Flush();    // Make sure any pending entry gets printed
+  fprintf(fout, "Offsetmap: %ld bytes\n", diffs_.size());
+  for (int i = 0; i < static_cast<int>(diffs_.size()); ++i) {
+    fprintf(fout, "%c%02d ", "&=+-"[OpPart(diffs_[i])], LenPart(diffs_[i]));
+    if ((i % 20) == 19) {fprintf(fout, "\n");}
+  }
+  fprintf(fout, "\n");
+  if (needs_close) {
+    fclose(fout);
+  }
+}
+
+// Reset to offset 0
+void OffsetMap::Reset() {
+  MaybeFlushAll();
+
+  next_diff_sub_ = 0;
+  current_lo_aoffset_ = 0;
+  current_hi_aoffset_ = 0;
+  current_lo_aprimeoffset_ = 0;
+  current_hi_aprimeoffset_ = 0;
+  current_diff_ = 0;
+}
+
+// Add to  mapping from A to A', specifying how many next bytes are
+// identical in A and A'
+void OffsetMap::Copy(int bytes) {
+  if (bytes == 0) {return;}
+  max_aoffset_ += bytes;           // Largest seen so far
+  max_aprimeoffset_ += bytes;      // Largest seen so far
+  if (pending_op_ == COPY_OP) {
+    pending_length_ += bytes;
+  } else {
+    Flush();
+    pending_op_ = COPY_OP;
+    pending_length_ = bytes;
+  }
+}
+
+// Add to mapping from A to A', specifying how many next bytes are
+// inserted in A' while not advancing in A at all
+void OffsetMap::Insert(int bytes){
+  if (bytes == 0) {return;}
+  max_aprimeoffset_ += bytes;      // Largest seen so far
+  if (pending_op_ == INSERT_OP) {
+    pending_length_ += bytes;
+  } else if ((bytes == 1) &&
+             (pending_op_ == DELETE_OP) && (pending_length_ == 1)) {
+    // Special-case exactly delete(1) insert(1) +> copy(1);
+    // all others backmap inserts to after deletes
+    pending_op_ = COPY_OP;
+  } else {
+    Flush();
+    pending_op_ = INSERT_OP;
+    pending_length_ = bytes;
+  }
+}
+
+// Add to mapping from A to A', specifying how many next bytes are
+// deleted from A while not advancing in A' at all
+void OffsetMap::Delete(int bytes){
+  if (bytes == 0) {return;}
+  max_aoffset_ += bytes;           // Largest seen so far
+  if (pending_op_ == DELETE_OP) {
+    pending_length_ += bytes;
+    } else if ((bytes == 1) &&
+               (pending_op_ == INSERT_OP) && (pending_length_ == 1)) {
+      // Special-case exactly insert(1) delete(1) => copy(1);
+      // all others backmap deletes to after insertss
+      pending_op_ = COPY_OP;
+  } else {
+    Flush();
+    pending_op_ = DELETE_OP;
+    pending_length_ = bytes;
+  }
+}
+
+void OffsetMap::Flush() {
+  if (pending_length_ == 0) {
+    return;
+  }
+  // We may be emitting a copy op just after a copy op because +1 -1 cancelled
+  // inbetween. If the lengths don't need a prefix byte, combine them
+  if ((pending_op_ == COPY_OP) && !diffs_.empty()) {
+    char c = diffs_[diffs_.size() - 1];
+    MapOp prior_op = static_cast<MapOp>(OpPart(c));
+    int prior_len = LenPart(c);
+    if ((prior_op == COPY_OP) && ((prior_len + pending_length_) <= 0x3f)) {
+      diffs_[diffs_.size() - 1] += pending_length_;
+      pending_length_ = 0;
+      return;
+    }
+  }
+  if (pending_length_ > 0x3f) {
+    bool non_zero_emitted = false;
+    for (int shift = 30; shift > 0; shift -= 6) {
+      int prefix = (pending_length_ >> shift) & 0x3f;
+      if ((prefix > 0) || non_zero_emitted) {
+        Emit(PREFIX_OP, prefix);
+        non_zero_emitted = true;
+      }
+    }
+  }
+  Emit(pending_op_, pending_length_ & 0x3f);
+  pending_length_ = 0;
+}
+
+
+// Add one more entry to copy one byte off the end, then flush
+void OffsetMap::FlushAll() {
+  Copy(1);
+  Flush();
+}
+
+// Flush all if necessary
+void OffsetMap::MaybeFlushAll() {
+  if ((0 < pending_length_) || diffs_.empty()) {
+    FlushAll();
+  }
+}
+
+// Len may be 0, for example as the low piece of length=64
+void OffsetMap::Emit(MapOp op, int len) {
+  char c = (static_cast<char>(op) << 6) | (len & 0x3f);
+  diffs_.push_back(c);
+}
+
+void OffsetMap::DumpString() {
+  for (int i = 0; i < static_cast<int>(diffs_.size()); ++i) {
+    fprintf(stderr, "%c%02d ", "&=+-"[OpPart(diffs_[i])], LenPart(diffs_[i]));
+  }
+  fprintf(stderr, "\n");
+
+  // Print running table of correspondences
+  fprintf(stderr, "       op      A =>  A'     (A forward-maps to A')\n");
+  int aoffset = 0;
+  int aprimeoffset = 0;
+  int length = 0;
+  for (int i = 0; i < static_cast<int>(diffs_.size()); ++i) {
+    char c = diffs_[i];
+    MapOp op = static_cast<MapOp>(OpPart(c));
+    int len = LenPart(c);
+    length = (length << 6) + len;
+    if (op == COPY_OP) {
+      aoffset += length;
+      aprimeoffset += length;
+      length = 0;
+    } else if (op == INSERT_OP) {
+      aoffset += 0;
+      aprimeoffset += length;
+      length = 0;
+    } else if (op == DELETE_OP) {
+      aoffset += length;
+      aprimeoffset += 0;
+      length = 0;
+    } else {              // (op == PREFIX_OP)
+      // Do nothing else
+    }
+    fprintf(stderr, "[%3d] %c%02d %6d %6d%s\n",
+            i, "&=+-"[op], len,
+            aoffset, aprimeoffset,
+            (next_diff_sub_ == i) ? " <==next_diff_sub_" : "");
+
+  }
+  fprintf(stderr, "\n");
+}
+
+void OffsetMap::DumpWindow() {
+  fprintf(stderr, "DumpWindow(A => A'): max_aoffset_ = %d, "
+                  "max_aprimeoffset_ = %d, next_diff_sub_ = %d<br>\n",
+          max_aoffset_, max_aprimeoffset_, next_diff_sub_);
+  fprintf(stderr, "A  [%u..%u)\n",
+          current_lo_aoffset_, current_hi_aoffset_);
+  fprintf(stderr, "A' [%u..%u)\n",
+          current_lo_aprimeoffset_, current_hi_aprimeoffset_);
+  fprintf(stderr, "  diff = %d\n", current_diff_);
+  DumpString();
+}
+
+//----------------------------------------------------------------------------//
+// The guts of the 2013 design                                                //
+// If there are three ranges a b c in  diffs_, we can be in one of five       //
+// states: LEFT of a, in ranges a b c, or RIGHT of c                          //
+// In each state, there are windows A[Alo..Ahi), A'[A'lo..A'hi) and diffs_    //
+// position next_diff_sub_                                                    //
+// There also are mapping constants max_aoffset_ and max_aprimeoffset_        //
+// If LEFT, Alo=Ahi=0, A'lo=A'hi=0 and next_diff_sub_=0                       //
+// If RIGHT, Alo=Ahi=max_aoffset_, A'lo=A'hi=max_aprimeoffset_ and            //
+//   next_diff_sub_=diffs_.size()                                             //
+// Otherwise, at least one of A[) and A'[) is non-empty and the first bytes   //
+//   correspond to each other. If range i is active, next_diff_sub_ is at     //
+//   the first byte of range i+1. Because of the length-prefix operator,      //
+//   an individual range item in diffs_ may be multiple bytes                 //
+// In all cases aprimeoffset = aoffset + current_diff_                        //
+//   i.e. current_diff_ = aprimeoffset - aoffset                              //
+//                                                                            //
+// In the degenerate case of diffs_.empty(), there are only two states        //
+//   LEFT and RIGHT and the mapping is the identity mapping.                  //
+// The initial state is LEFT.                                                 //
+// It is an error to move left into LEFT or right into RIGHT, but the code    //
+//   below is robust in these cases.                                          //
+//----------------------------------------------------------------------------//
+
+void OffsetMap::SetLeft() {
+   current_lo_aoffset_ = 0;
+   current_hi_aoffset_ = 0;
+   current_lo_aprimeoffset_ = 0;
+   current_hi_aprimeoffset_ = 0;
+   current_diff_ = 0;
+   next_diff_sub_ = 0;
+}
+
+void OffsetMap::SetRight() {
+   current_lo_aoffset_ = max_aoffset_;
+   current_hi_aoffset_ = max_aoffset_;
+   current_lo_aprimeoffset_ = max_aprimeoffset_;
+   current_hi_aprimeoffset_ = max_aprimeoffset_;
+   current_diff_ = max_aprimeoffset_ - max_aoffset_;
+   next_diff_sub_ = 0;
+}
+
+// Back up over previous range, 1..5 bytes
+// Return subscript at the beginning of that. Pins at 0
+int OffsetMap::Backup(int sub) {
+  if (sub <= 0) {return 0;}
+  --sub;
+  while ((0 < sub) &&
+         (static_cast<MapOp>(OpPart(diffs_[sub - 1]) == PREFIX_OP))) {
+    --sub;
+  }
+  return sub;
+}
+
+// Parse next range, 1..5 bytes
+// Return subscript just off the end of that
+int OffsetMap::ParseNext(int sub, MapOp* op, int* length) {
+   *op = PREFIX_OP;
+   *length = 0;
+   char c;
+   while ((sub < static_cast<int>(diffs_.size())) && (*op == PREFIX_OP)) {
+     c = diffs_[sub++];
+     *op = static_cast<MapOp>(OpPart(c));
+     int len = LenPart(c);
+     *length = (*length << 6) + len;
+   }
+   // If mal-formed or in RIGHT, this will return with op = PREFIX_OP
+   // Mal-formed can include a trailing prefix byte with no following op
+   return sub;
+}
+
+// Parse previous range, 1..5 bytes
+// Return current subscript
+int OffsetMap::ParsePrevious(int sub, MapOp* op, int* length) {
+  sub = Backup(sub);
+  return ParseNext(sub, op, length);
+}
+
+// Quick debugging dump; does not parse multi-byte items, so just length & 0x3f
+void OffsetMap::PrintPosition(const char* str) {
+  MapOp op = PREFIX_OP;
+  int length = 0;
+  if ((0 < next_diff_sub_) && (next_diff_sub_ <= static_cast<int>(diffs_.size()))) {
+    op = static_cast<MapOp>(OpPart(diffs_[next_diff_sub_ - 1]));
+    length = LenPart(diffs_[next_diff_sub_ - 1]);
+  }
+  fprintf(stderr, "%s[%d] %c%02d = A[%d..%d) ==> A'[%d..%d)\n",
+          str,
+          next_diff_sub_, "&=+-"[op], length,
+          current_lo_aoffset_, current_hi_aoffset_,
+          current_lo_aprimeoffset_, current_hi_aprimeoffset_);
+}
+
+// Move active window one range to the right
+// Return true if move was OK
+bool OffsetMap::MoveRight() {
+  // If at last range or RIGHT, set to RIGHT, return error
+  if (next_diff_sub_ >= static_cast<int>(diffs_.size())) {
+    SetRight();
+    return false;
+  }
+  // Actually OK to move right
+  MapOp op;
+  int length;
+  bool retval = true;
+  // If mal-formed or in RIGHT, this will return with op = PREFIX_OP
+  next_diff_sub_ = ParseNext(next_diff_sub_, &op, &length);
+
+  current_lo_aoffset_ = current_hi_aoffset_;
+  current_lo_aprimeoffset_ = current_hi_aprimeoffset_;
+  if (op == COPY_OP) {
+    current_hi_aoffset_ = current_lo_aoffset_ + length;
+    current_hi_aprimeoffset_ = current_lo_aprimeoffset_ + length;
+  } else if (op == INSERT_OP) {
+    current_hi_aoffset_ = current_lo_aoffset_ + 0;
+    current_hi_aprimeoffset_ = current_lo_aprimeoffset_ + length;
+  } else if (op == DELETE_OP) {
+    current_hi_aoffset_ = current_lo_aoffset_ + length;
+    current_hi_aprimeoffset_ = current_lo_aprimeoffset_ + 0;
+  } else {
+    SetRight();
+    retval = false;
+  }
+  current_diff_ = current_lo_aprimeoffset_ - current_lo_aoffset_;
+  return retval;
+}
+
+// Move active window one range to the left
+// Return true if move was OK
+bool OffsetMap::MoveLeft() {
+  // If at first range or LEFT, set to LEFT, return error
+  if (next_diff_sub_ <= 0) {
+    SetLeft();
+    return false;
+  }
+  // Back up over current active window
+  next_diff_sub_ = Backup(next_diff_sub_);
+  if (next_diff_sub_ <= 0) {
+    SetLeft();
+    return false;
+  }
+  // Actually OK to move left
+  MapOp op;
+  int length;
+  bool retval = true;
+  // If mal-formed or in LEFT, this will return with op = PREFIX_OP
+  next_diff_sub_ = ParsePrevious(next_diff_sub_, &op, &length);
+
+  current_hi_aoffset_ = current_lo_aoffset_;
+  current_hi_aprimeoffset_ = current_lo_aprimeoffset_;
+  if (op == COPY_OP) {
+    current_lo_aoffset_ = current_hi_aoffset_ - length;
+    current_lo_aprimeoffset_ = current_hi_aprimeoffset_ - length;
+  } else if (op == INSERT_OP) {
+    current_lo_aoffset_ = current_hi_aoffset_ - 0;
+    current_lo_aprimeoffset_ = current_hi_aprimeoffset_ - length;
+  } else if (op == DELETE_OP) {
+    current_lo_aoffset_ = current_hi_aoffset_ - length;
+    current_lo_aprimeoffset_ = current_hi_aprimeoffset_ - 0;
+  } else {
+    SetLeft();
+    retval = false;
+  }
+  current_diff_ = current_lo_aprimeoffset_ - current_lo_aoffset_;
+  return true;
+}
+
+// Map an offset in A' to the corresponding offset in A
+int OffsetMap::MapBack(int aprimeoffset){
+  MaybeFlushAll();
+  if (aprimeoffset < 0) {return 0;}
+  if (max_aprimeoffset_ <= aprimeoffset) {
+     return (aprimeoffset - max_aprimeoffset_) + max_aoffset_;
+  }
+
+  // If current_lo_aprimeoffset_ <= aprimeoffset < current_hi_aprimeoffset_,
+  // use current mapping, else move window left/right
+  bool ok = true;
+  while (ok && (aprimeoffset < current_lo_aprimeoffset_)) {
+    ok = MoveLeft();
+  }
+  while (ok && (current_hi_aprimeoffset_ <= aprimeoffset)) {
+    ok = MoveRight();
+  }
+  // So now current_lo_aprimeoffset_ <= aprimeoffset < current_hi_aprimeoffset_
+
+  int aoffset = aprimeoffset - current_diff_;
+  if (aoffset >= current_hi_aoffset_) {
+    // A' is in an insert region, all bytes of which backmap to A=hi_aoffset_
+    aoffset = current_hi_aoffset_;
+  }
+  return aoffset;
+}
+
+// Map an offset in A to the corresponding offset in A'
+int OffsetMap::MapForward(int aoffset){
+  MaybeFlushAll();
+  if (aoffset < 0) {return 0;}
+  if (max_aoffset_ <= aoffset) {
+     return (aoffset - max_aoffset_) + max_aprimeoffset_;
+  }
+
+  // If current_lo_aoffset_ <= aoffset < current_hi_aoffset_,
+  // use current mapping, else move window left/right
+  bool ok = true;
+  while (ok && (aoffset < current_lo_aoffset_)) {
+    ok = MoveLeft();
+  }
+  while (ok && (current_hi_aoffset_ <= aoffset)) {
+    ok = MoveRight();
+  }
+
+  int aprimeoffset = aoffset + current_diff_;
+  if (aprimeoffset >= current_hi_aprimeoffset_) {
+    // A is in a delete region, all bytes of which map to A'=hi_aprimeoffset_
+    aprimeoffset = current_hi_aprimeoffset_;
+  }
+  return aprimeoffset;
+}
+
+
+// static
+bool OffsetMap::CopyInserts(OffsetMap* source, OffsetMap* dest) {
+  bool ok = true;
+  while (ok && (source->next_diff_sub_ != source->diffs_.size())) {
+    ok = source->MoveRight();
+    if (source->current_lo_aoffset_ != source->current_hi_aoffset_) {
+      return false;
+    }
+    dest->Insert(
+        source->current_hi_aprimeoffset_ - source->current_lo_aprimeoffset_);
+  }
+  return true;
+}
+
+// static
+bool OffsetMap::CopyDeletes(OffsetMap* source, OffsetMap* dest) {
+  bool ok = true;
+  while (ok && (source->next_diff_sub_ != source->diffs_.size())) {
+    ok = source->MoveRight();
+    if (source->current_lo_aprimeoffset_ != source->current_hi_aprimeoffset_) {
+      return false;
+    }
+    dest->Delete(source->current_hi_aoffset_ - source->current_lo_aoffset_);
+  }
+  return true;
+}
+
+// static
+void OffsetMap::ComposeOffsetMap(
+    OffsetMap* g, OffsetMap* f, OffsetMap* h) {
+  h->Clear();
+  f->Reset();
+  g->Reset();
+
+  int lo = 0;
+  for (;;) {
+     // Consume delete operations in f. This moves A without moving
+     // A' and A''.
+     if (lo >= g->current_hi_aoffset_ && CopyInserts(g, h)) {
+       if (lo >= f->current_hi_aprimeoffset_ && CopyDeletes(f, h)) {
+          // fprintf(stderr,
+          //         "ComposeOffsetMap ERROR, f is longer than g.<br>\n");
+       }
+
+       // FlushAll(), called by Reset(), MapForward() or MapBack(), has
+       // added an extra COPY_OP to f and g, so this function has
+       // composed an extra COPY_OP in h from those. To avoid
+       // FlushAll() adds one more extra COPY_OP to h later, dispatch
+       // Flush() right now.
+       h->Flush();
+       return;
+     }
+
+     // Consume insert operations in g. This moves A'' without moving A
+     // and A'.
+     if (lo >= f->current_hi_aprimeoffset_) {
+       if (!CopyDeletes(f, h)) {
+          // fprintf(stderr,
+          //         "ComposeOffsetMap ERROR, g is longer than f.<br>\n");
+       }
+     }
+
+     // Compose one operation which moves A' from lo to hi.
+     int hi = min(f->current_hi_aprimeoffset_, g->current_hi_aoffset_);
+     if (f->current_lo_aoffset_ != f->current_hi_aoffset_ &&
+         g->current_lo_aprimeoffset_ != g->current_hi_aprimeoffset_) {
+       h->Copy(hi - lo);
+     } else if (f->current_lo_aoffset_ != f->current_hi_aoffset_) {
+       h->Delete(hi - lo);
+     } else if (g->current_lo_aprimeoffset_ != g->current_hi_aprimeoffset_) {
+       h->Insert(hi - lo);
+     }
+
+     lo = hi;
+  }
+}
+
+// For testing only -- force a mapping
+void OffsetMap::StuffIt(const string& diffs,
+                        int max_aoffset, int max_aprimeoffset) {
+  Clear();
+  diffs_ = diffs;
+  max_aoffset_ = max_aoffset;
+  max_aprimeoffset_ = max_aprimeoffset;
+}
+
+
+}  // namespace CLD2
+