diff options
Diffstat (limited to 'gold/script.h')
-rw-r--r-- | gold/script.h | 120 |
1 files changed, 119 insertions, 1 deletions
diff --git a/gold/script.h b/gold/script.h index 16caf03..0dfa4bb 100644 --- a/gold/script.h +++ b/gold/script.h @@ -1,6 +1,6 @@ // script.h -- handle linker scripts for gold -*- C++ -*- -// Copyright 2006, 2007 Free Software Foundation, Inc. +// Copyright 2006, 2007, 2008 Free Software Foundation, Inc. // Written by Ian Lance Taylor <iant@google.com>. // This file is part of gold. @@ -30,6 +30,8 @@ #ifndef GOLD_SCRIPT_H #define GOLD_SCRIPT_H +#include <vector> + namespace gold { @@ -41,9 +43,125 @@ class Input_argument; class Input_objects; class Input_group; class Input_file; +class Target; class Task_token; class Workqueue; +// This class represents an expression in a linker script. + +class Expression +{ + protected: + // These should only be created by child classes. + Expression() + { } + + public: + virtual ~Expression() + { } + + // Return the value of the expression. + uint64_t + eval(const Symbol_table*, const Layout*); + + protected: + struct Expression_eval_info; + + public: + // Compute the value of the expression (implemented by child class). + // This is public rather than protected because it is called + // directly by children of Expression on other Expression objects. + virtual uint64_t + value(const Expression_eval_info*) = 0; + + private: + // May not be copied. + Expression(const Expression&); + Expression& operator=(const Expression&); +}; + +// We can read a linker script in two different contexts: when +// initially parsing the command line, and when we find an input file +// which is actually a linker script. Also some of the data which can +// be set by a linker script can also be set via command line options +// like -e and --defsym. This means that we have a type of data which +// can be set both during command line option parsing and while +// reading input files. We store that data in an instance of this +// object. We will keep pointers to that instance in both the +// Command_line and Layout objects. + +class Script_options +{ + public: + Script_options(); + + // The entry address. + const char* + entry() const + { return this->entry_.empty() ? NULL : this->entry_.c_str(); } + + // Set the entry address. + void + set_entry(const char* entry, size_t length) + { this->entry_.assign(entry, length); } + + // Add a symbol to be defined. These are for symbol definitions + // which appear outside of a SECTIONS clause. + void + add_symbol_assignment(const char* name, size_t length, Expression* value, + bool provided, bool hidden) + { + this->symbol_assignments_.push_back(Symbol_assignment(name, length, value, + provided, hidden)); + } + + // Define a symbol from the command line. + bool + define_symbol(const char* definition); + + // Add all symbol definitions to the symbol table. + void + add_symbols_to_table(Symbol_table*, const Target*); + + // Finalize the symbol values. + void + finalize_symbols(Symbol_table*, const Layout*); + + private: + // We keep a list of symbol assignments. + struct Symbol_assignment + { + // Symbol name. + std::string name; + // Expression to assign to symbol. + Expression* value; + // Whether the assignment should be provided (only set if there is + // an undefined reference to the symbol. + bool provide; + // Whether the assignment should be hidden. + bool hidden; + // The entry in the symbol table. + Symbol* sym; + + Symbol_assignment(const char* namea, size_t lengtha, Expression* valuea, + bool providea, bool hiddena) + : name(namea, lengtha), value(valuea), provide(providea), + hidden(hiddena), sym(NULL) + { } + }; + + typedef std::vector<Symbol_assignment> Symbol_assignments; + + template<int size> + void + sized_finalize_symbols(Symbol_table*, const Layout*); + + // The entry address. This will be empty if not set. + std::string entry_; + // Symbols to set. + Symbol_assignments symbol_assignments_; +}; + // FILE was found as an argument on the command line, but was not // recognized as an ELF file. Try to read it as a script. We've // already read BYTES of data into P. Return true if the file was |