1 files changed, 98 insertions, 0 deletions
diff --git a/testing/segment.h b/testing/segment.h
new file mode 100644
index 0000000..ea3dcee
--- /dev/null
+++ b/testing/segment.h
@@ -0,0 +1,98 @@
+// -*- Mode: C++ -*-
+
+class Segment {
+ public:
+  Segment(size_t size, MTRandom *rand)
+    : size_(size),
+      seed_(rand->Rand32()),
+      seed_offset_(0),
+      data_(NULL) {
+    CHECK_GT(size_, 0);
+  }
+
+  Segment(size_t size, uint32_t seed)
+    : size_(size),
+      seed_(seed),
+      seed_offset_(0),
+      data_(NULL) {
+    CHECK_GT(size_, 0);
+  }
+
+  Segment(size_t size, uint8_t *data)
+    : size_(size),
+      seed_(0),
+      seed_offset_(0),
+      data_(data) {
+    CHECK_GT(size_, 0);
+  }
+
+  size_t Size() const {
+    return size_;
+  }
+
+  Segment Subseg(size_t start, size_t size) const {
+    CHECK_LE(start + size, size_);
+    if (data_) {
+      return Segment(size, data_ + start);
+    } else {
+      return Segment(size, seed_, seed_offset_ + start);
+    }
+  }
+
+  void Fill(size_t seg_offset, size_t size, uint8_t *data) const {
+    CHECK_LE(seg_offset + size, size_);
+    if (data_) {
+      memcpy(data, data_ + seg_offset, size);
+    } else {
+      size_t skip = seg_offset + seed_offset_;
+      MTRandom gen(seed_);
+      MTRandom8 gen8(&gen);
+      while (skip--) {
+	gen8.Rand8();
+      }
+      for (size_t i = 0; i < size; i++) {
+	data[i] = gen8.Rand8();
+      }
+    }
+  }
+
+  string ToString() const {
+    string r;
+    if (data_) {
+      for (size_t i = 0; i < size_; i++) {
+	char buf[10];
+	sprintf(buf, "%02x ", data_[i]);
+	r.append(buf);
+      }
+    } else {
+      char buf[256];
+      sprintf(buf, "size=%ld,seed=%ud,skip=%ld", size_, seed_, seed_offset_);
+      r.append(buf);
+    }
+    return r;
+  }
+
+private:
+  // Used by Subseg()
+  Segment(size_t size, uint32_t seed, size_t seed_offset)
+    : size_(size),
+      seed_(seed),
+      seed_offset_(seed_offset),
+      data_(NULL) {
+    CHECK_GT(size_, 0);
+  }
+
+  size_t size_;  // Size of this segment
+
+  // For random segments
+  uint32_t seed_;  // Seed used for generating byte sequence
+  size_t seed_offset_;  // Seed positions the sequence this many bytes
+                        // before its beginning.
+
+  // For literal segments (data is not owned)
+  uint8_t *data_;
+};
+
+typedef map<xoff_t, Segment> SegmentMap;
+typedef typename SegmentMap::const_iterator ConstSegmentMapIterator;
+typedef typename SegmentMap::iterator SegmentMapIterator;