2007-03-09 H.J. Lu <hongjiu.lu@intel.com>

[deliverable/binutils-gdb.git] / gold / stringpool.h

diff --git a/gold/stringpool.h b/gold/stringpool.h
index 873c26a645a03313332d1c5a6e2765236083cdee..05c498e49fac165faab2cf566cb5c0af67b7877f 100644 (file)
--- a/gold/stringpool.h
+++ b/gold/stringpool.h
@@ -12,38 +12,86 @@
 namespace gold
 {
 
+class Output_file;
+
 class Stringpool
 {
  public:
+  // The type of a key into the stringpool.  A key value will always
+  // be the same during any run of the linker.  The string pointers
+  // may change when using address space randomization.  We use key
+  // values in order to get repeatable runs when the value is inserted
+  // into an unordered hash table.  Zero is never a valid key.
+  typedef size_t Key;
+
   Stringpool();
 
   ~Stringpool();
 
   // Add a string to the pool.  This returns a canonical permanent
-  // pointer to the string.
-  const char* add(const char*);
+  // pointer to the string.  If PKEY is not NULL, this sets *PKEY to
+  // the key for the string.
+  const char*
+  add(const char*, Key* pkey);
 
-  const char* add(const std::string& s)
-  { return this->add(s.c_str()); }
+  const char*
+  add(const std::string& s, Key* pkey)
+  { return this->add(s.c_str(), pkey); }
 
   // Add the prefix of a string to the pool.
-  const char* add(const char *, size_t);
+  const char*
+  add(const char *, size_t, Key* pkey);
+
+  // If a string is present, return the canonical string.  Otherwise,
+  // return NULL.  If PKEY is not NULL, set *PKEY to the key.
+  const char*
+  find(const char*, Key* pkey) const;
+
+  // Turn the stringpool into an ELF strtab: determine the offsets of
+  // all the strings.
+  void
+  set_string_offsets();
+
+  // Get the offset of a string in an ELF strtab.
+  off_t
+  get_offset(const char*) const;
+
+  off_t
+  get_offset(const std::string& s) const
+  { return this->get_offset(s.c_str()); }
+
+  // Get the size of the ELF strtab.
+  off_t
+  get_strtab_size() const
+  {
+    gold_assert(this->strtab_size_ != 0);
+    return this->strtab_size_;
+  }
+
+  // Write the strtab into the output file at the specified offset.
+  void
+  write(Output_file*, off_t offset);
 
  private:
   Stringpool(const Stringpool&);
   Stringpool& operator=(const Stringpool&);
 
-  struct stringdata
+  // We store the actual data in a list of these buffers.
+  struct Stringdata
   {
     // Length of data in buffer.
     size_t len;
     // Allocated size of buffer.
     size_t alc;
+    // Buffer index.
+    unsigned int index;
     // Buffer.
     char data[1];
   };
 
-  const char* add_string(const char*);
+  // Copy a string into the buffers, returning a canonical string.
+  const char*
+  add_string(const char*, Key*);
 
   struct Stringpool_hash
   {
@@ -58,11 +106,45 @@ class Stringpool
     { return strcmp(p1, p2) == 0; }
   };
 
-  typedef Unordered_set<const char*, Stringpool_hash, Stringpool_eq,
-                       std::allocator<const char*>,
+  // Return whether s1 is a suffix of s2.
+  static bool is_suffix(const char* s1, const char* s2);
+
+  // The hash table is a map from string names to a pair of Key and
+  // ELF strtab offsets.  We only use the offsets if we turn this into
+  // an ELF strtab section.
+
+  typedef std::pair<Key, off_t> Val;
+
+#ifdef HAVE_TR1_UNORDERED_SET
+  typedef Unordered_map<const char*, Val, Stringpool_hash,
+                       Stringpool_eq,
+                       std::allocator<std::pair<const char* const, Val> >,
                        true> String_set_type;
+#else
+  typedef Unordered_map<const char*, Val, Stringpool_hash,
+                       Stringpool_eq> String_set_type;
+#endif
+
+  // Comparison routine used when sorting into an ELF strtab.
+
+  struct Stringpool_sort_comparison
+  {
+    bool
+    operator()(String_set_type::iterator,
+              String_set_type::iterator) const;
+  };
+
+  // List of Stringdata structures.
+  typedef std::list<Stringdata*> Stringdata_list;
+
+  // Mapping from const char* to namepool entry.
   String_set_type string_set_;
-  std::list<stringdata*> strings_;
+  // List of buffers.
+  Stringdata_list strings_;
+  // Size of ELF strtab.
+  off_t strtab_size_;
+  // Next Stringdata index.
+  unsigned int next_index_;
 };
 
 } // End namespace gold.