gold/archive.h

   1 // archive.h -- archive support for gold      -*- C++ -*-
   2
   3 #ifndef GOLD_ARCHIVE_H
   4 #define GOLD_ARCHIVE_H
   5
   6 #include <string>
   7 #include <vector>
   8
   9 #include "workqueue.h"
  10
  11 namespace gold
  12 {
  13
  14 class Input_file;
  15 class Input_objects;
  16 class Layout;
  17 class Symbol_table;
  18
  19 // This class represents an archive--generally a libNAME.a file.
  20 // Archives have a symbol table and a list of objects.
  21
  22 class Archive
  23 {
  24  public:
  25   Archive(const std::string& name, Input_file* input_file)
  26     : name_(name), input_file_(input_file), armap_(), extended_names_()
  27   { }
  28
  29   // The length of the magic string at the start of an archive.
  30   static const int sarmag = 8;
  31
  32   // The magic string at the start of an archive.
  33   static const char armag[sarmag];
  34
  35   // The string expected at the end of an archive member header.
  36   static const char arfmag[2];
  37
  38   // The name of the object.
  39   const std::string&
  40   name() const
  41   { return this->name_; }
  42
  43   // Set up the archive: read the symbol map.
  44   void
  45   setup();
  46
  47   // Lock the underlying file.
  48   void
  49   lock()
  50   { this->input_file_->file().lock(); }
  51
  52   // Unlock the underlying file.
  53   void
  54   unlock()
  55   { this->input_file_->file().unlock(); }
  56
  57   // Return whether the underlying file is locked.
  58   bool
  59   is_locked() const
  60   { return this->input_file_->file().is_locked(); }
  61
  62   // Select members from the archive as needed and add them to the
  63   // link.
  64   void
  65   add_symbols(Symbol_table*, Layout*, Input_objects*);
  66
  67  private:
  68   Archive(const Archive&);
  69   Archive& operator=(const Archive&);
  70
  71   struct Archive_header;
  72   class Add_archive_symbols_locker;
  73
  74   // Get a view into the underlying file.
  75   const unsigned char*
  76   get_view(off_t start, off_t size);
  77
  78   // Read an archive member header at OFF.  Return the size of the
  79   // member, and set *PNAME to the name.
  80   off_t
  81   read_header(off_t off, std::string* pname);
  82
  83   // Include an archive member in the link.
  84   void
  85   include_member(Symbol_table*, Layout*, Input_objects*, off_t off);
  86
  87   // An entry in the archive map of symbols to object files.
  88   struct Armap_entry
  89   {
  90     // The symbol name.
  91     const char* name;
  92     // The offset to the file.
  93     off_t offset;
  94   };
  95
  96   // Name of object as printed to user.
  97   std::string name_;
  98   // For reading the file.
  99   Input_file* input_file_;
 100   // The archive map.
 101   std::vector<Armap_entry> armap_;
 102   // The extended name table.
 103   std::string extended_names_;
 104 };
 105
 106 // This class is used to read an archive and pick out the desired
 107 // elements and add them to the link.
 108
 109 class Add_archive_symbols : public Task
 110 {
 111  public:
 112   Add_archive_symbols(Symbol_table* symtab, Layout* layout,
 113                       Input_objects* input_objects,
 114                       Archive* archive, Task_token* this_blocker,
 115                       Task_token* next_blocker)
 116     : symtab_(symtab), layout_(layout), input_objects_(input_objects),
 117       archive_(archive), this_blocker_(this_blocker),
 118       next_blocker_(next_blocker)
 119   { }
 120
 121   ~Add_archive_symbols();
 122
 123   // The standard Task methods.
 124
 125   Is_runnable_type
 126   is_runnable(Workqueue*);
 127
 128   Task_locker*
 129   locks(Workqueue*);
 130
 131   void
 132   run(Workqueue*);
 133
 134  private:
 135   class Add_archive_symbols_locker;
 136
 137   Symbol_table* symtab_;
 138   Layout* layout_;
 139   Input_objects* input_objects_;
 140   Archive* archive_;
 141   Task_token* this_blocker_;
 142   Task_token* next_blocker_;
 143 };
 144
 145 } // End namespace gold.
 146
 147 #endif // !defined(GOLD_ARCHIVE_H)