+// A base class for Verdef and Verneed_version which just handles the
+// version index which will be stored in the SHT_GNU_versym section.
+
+class Version_base
+{
+ public:
+ Version_base()
+ : index_(-1U)
+ { }
+
+ virtual
+ ~Version_base()
+ { }
+
+ // Return the version index.
+ unsigned int
+ index() const
+ {
+ gold_assert(this->index_ != -1U);
+ return this->index_;
+ }
+
+ // Set the version index.
+ void
+ set_index(unsigned int index)
+ {
+ gold_assert(this->index_ == -1U);
+ this->index_ = index;
+ }
+
+ // Clear the weak flag in a version definition.
+ virtual void
+ clear_weak() = 0;
+
+ private:
+ Version_base(const Version_base&);
+ Version_base& operator=(const Version_base&);
+
+ // The index of the version definition or reference.
+ unsigned int index_;
+};
+
+// This class handles a version being defined in the file we are
+// generating.
+
+class Verdef : public Version_base
+{
+ public:
+ Verdef(const char* name, bool is_base, bool is_weak, bool is_symbol_created)
+ : name_(name), deps_(), is_base_(is_base), is_weak_(is_weak),
+ is_symbol_created_(is_symbol_created)
+ { }
+
+ // Return the version name.
+ const char*
+ name() const
+ { return this->name_; }
+
+ // Return the number of dependencies.
+ unsigned int
+ count_dependencies() const
+ { return this->deps_.size(); }
+
+ // Add a dependency to this version. The NAME should be
+ // canonicalized in the dynamic Stringpool.
+ void
+ add_dependency(const char* name)
+ { this->deps_.push_back(name); }
+
+ // Return whether this definition is weak.
+ bool
+ is_weak() const
+ { return this->is_weak_; }
+
+ // Clear the weak flag.
+ void
+ clear_weak()
+ { this->is_weak_ = false; }
+
+ // Return whether a version symbol has been created for this
+ // definition.
+ bool
+ is_symbol_created() const
+ { return this->is_symbol_created_; }
+
+ // Write contents to buffer.
+ template<int size, bool big_endian>
+ unsigned char*
+ write(const Stringpool*, bool is_last, unsigned char*
+ ACCEPT_SIZE_ENDIAN) const;
+
+ private:
+ Verdef(const Verdef&);
+ Verdef& operator=(const Verdef&);
+
+ // The type of the list of version dependencies. Each dependency
+ // should be canonicalized in the dynamic Stringpool.
+ typedef std::vector<const char*> Deps;
+
+ // The name of this version. This should be canonicalized in the
+ // dynamic Stringpool.
+ const char* name_;
+ // A list of other versions which this version depends upon.
+ Deps deps_;
+ // Whether this is the base version.
+ bool is_base_;
+ // Whether this version is weak.
+ bool is_weak_;
+ // Whether a version symbol has been created.
+ bool is_symbol_created_;
+};
+
+// A referened version. This will be associated with a filename by
+// Verneed.
+
+class Verneed_version : public Version_base
+{
+ public:
+ Verneed_version(const char* version)
+ : version_(version)
+ { }
+
+ // Return the version name.
+ const char*
+ version() const
+ { return this->version_; }
+
+ // Clear the weak flag. This is invalid for a reference.
+ void
+ clear_weak()
+ { gold_unreachable(); }
+
+ private:
+ Verneed_version(const Verneed_version&);
+ Verneed_version& operator=(const Verneed_version&);
+
+ const char* version_;
+};
+
+// Version references in a single dynamic object.
+
+class Verneed
+{
+ public:
+ Verneed(const char* filename)
+ : filename_(filename), need_versions_()
+ { }
+
+ ~Verneed();
+
+ // Return the file name.
+ const char*
+ filename() const
+ { return this->filename_; }
+
+ // Return the number of versions.
+ unsigned int
+ count_versions() const
+ { return this->need_versions_.size(); }
+
+ // Add a version name. The name should be canonicalized in the
+ // dynamic Stringpool. If the name is already present, this does
+ // nothing.
+ Verneed_version*
+ add_name(const char* name);
+
+ // Set the version indexes, starting at INDEX. Return the updated
+ // INDEX.
+ unsigned int
+ finalize(unsigned int index);
+
+ // Write contents to buffer.
+ template<int size, bool big_endian>
+ unsigned char*
+ write(const Stringpool*, bool is_last, unsigned char*
+ ACCEPT_SIZE_ENDIAN) const;
+
+ private:
+ Verneed(const Verneed&);
+ Verneed& operator=(const Verneed&);
+
+ // The type of the list of version names. Each name should be
+ // canonicalized in the dynamic Stringpool.
+ typedef std::vector<Verneed_version*> Need_versions;
+
+ // The filename of the dynamic object. This should be
+ // canonicalized in the dynamic Stringpool.
+ const char* filename_;
+ // The list of version names.
+ Need_versions need_versions_;
+};
+
+// This class handles version definitions and references which go into
+// the output file.
+
+class Versions
+{
+ public:
+ Versions()
+ : defs_(), needs_(), version_table_(), is_finalized_(false)
+ { }
+
+ ~Versions();
+
+ // SYM is going into the dynamic symbol table and has a version.
+ // Record the appropriate version information.
+ void
+ record_version(const General_options*, Stringpool*, const Symbol* sym);
+
+ // Set the version indexes. DYNSYM_INDEX is the index we should use
+ // for the next dynamic symbol. We add new dynamic symbols to SYMS
+ // and return an updated DYNSYM_INDEX.
+ unsigned int
+ finalize(const Target*, Symbol_table* symtab, unsigned int dynsym_index,
+ std::vector<Symbol*>* syms);
+
+ // Return whether there are any version definitions.
+ bool
+ any_defs() const
+ { return !this->defs_.empty(); }
+
+ // Return whether there are any version references.
+ bool
+ any_needs() const
+ { return !this->needs_.empty(); }
+
+ // Build an allocated buffer holding the contents of the symbol
+ // version section (.gnu.version).
+ template<int size, bool big_endian>
+ void
+ symbol_section_contents(const Stringpool*, unsigned int local_symcount,
+ const std::vector<Symbol*>& syms,
+ unsigned char**, unsigned int*
+ ACCEPT_SIZE_ENDIAN) const;
+
+ // Build an allocated buffer holding the contents of the version
+ // definition section (.gnu.version_d).
+ template<int size, bool big_endian>
+ void
+ def_section_contents(const Stringpool*, unsigned char**,
+ unsigned int* psize, unsigned int* pentries
+ ACCEPT_SIZE_ENDIAN) const;
+
+ // Build an allocated buffer holding the contents of the version
+ // reference section (.gnu.version_r).
+ template<int size, bool big_endian>
+ void
+ need_section_contents(const Stringpool*, unsigned char**,
+ unsigned int* psize, unsigned int* pentries
+ ACCEPT_SIZE_ENDIAN) const;
+
+ private:
+ // The type of the list of version definitions.
+ typedef std::vector<Verdef*> Defs;
+
+ // The type of the list of version references.
+ typedef std::vector<Verneed*> Needs;
+
+ // Handle a symbol SYM defined with version VERSION.
+ void
+ add_def(const General_options*, const Symbol* sym, const char* version,
+ Stringpool::Key);
+
+ // Add a reference to version NAME in file FILENAME.
+ void
+ add_need(Stringpool*, const char* filename, const char* name,
+ Stringpool::Key);
+
+ // Return the version index to use for SYM.
+ unsigned int
+ version_index(const Stringpool*, const Symbol* sym) const;
+
+ // We keep a hash table mapping canonicalized name/version pairs to
+ // a version base.
+ typedef std::pair<Stringpool::Key, Stringpool::Key> Key;
+
+ struct Version_table_hash
+ {
+ size_t
+ operator()(const Key& k) const
+ { return k.first + k.second; }
+ };
+
+ struct Version_table_eq
+ {
+ bool
+ operator()(const Key& k1, const Key& k2) const
+ { return k1.first == k2.first && k1.second == k2.second; }
+ };
+
+ typedef Unordered_map<Key, Version_base*, Version_table_hash,
+ Version_table_eq> Version_table;
+
+ // The version definitions.
+ Defs defs_;
+ // The version references.
+ Needs needs_;
+ // The mapping from a canonicalized version/filename pair to a
+ // version index. The filename may be NULL.
+ Version_table version_table_;
+ // Whether the version indexes have been set.
+ bool is_finalized_;
+};
+