rtl-sym.h

/*
 *  COPYRIGHT (c) 2012 Chris Johns <chrisj@rtems.org>
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.com/license/LICENSE.
 */
/**
 * @file
 *
 * @ingroup rtems_rtl
 *
 * @brief RTEMS Run-Time Linker Object File Symbol Table.
 */

#if !defined (_RTEMS_RTL_SYM_H_)
#define _RTEMS_RTL_SYM_H_

#include <rtems.h>
#include <rtl-obj-fwd.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/**
 * An object file symbol.
 */
typedef struct rtems_rtl_obj_sym_s
{
  rtems_chain_node node;    /**< The node's link in the chain. */
  const char*      name;    /**< The symbol's name. */
  void*            value;   /**< The value of the symbol. */
  uint32_t         data;    /**< Format specific data. */
} rtems_rtl_obj_sym_t;

/**
 * Table of symbols stored in a hash table.
 */
typedef struct rtems_rtl_symbols_s
{
  rtems_chain_control* buckets;
  size_t               nbuckets;
} rtems_rtl_symbols_t;

/**
 * Open a symbol table with the specified number of buckets.
 *
 * @param symbols The symbol table to open.
 * @param buckets The number of buckets in the hash table.
 * @retval true The symbol is open.
 * @retval false The symbol table could not created. The RTL
 *               error has the error.
 */
bool rtems_rtl_symbol_table_open (rtems_rtl_symbols_t* symbols,
                                  size_t               buckets);

/**
 * Close the table and erase the hash table.
 *
 * @param symbols Close the symbol table.
 */
void rtems_rtl_symbol_table_close (rtems_rtl_symbols_t* symbols);

/**
 * Add a table of exported symbols to the symbol table.
 *
 * The export table is a series of symbol records and each record has two
 * fields:
 *
 *  1. label
 *  2. address
 *
 * The 'label' is an ASCIIZ string of variable length. The address is of size
 * of an unsigned long for the target running the link editor. The byte order
 * is defined by the machine type because the table should be built by the
 * target compiler.
 *
 * The table is terminated with a nul string followed by the bytes 0xDE, 0xAD,
 * 0xBE, and 0xEF. This avoids alignments issues.
 *
 * @param obj The object table the symbols are for.
 * @param esyms The exported symbol table.
 * @param size The size of the table in bytes.
 */
bool rtems_rtl_symbol_global_add (rtems_rtl_obj_t*     obj,
                                  const unsigned char* esyms,
                                  unsigned int         size);

/**
 * Find a symbol given the symbol label in the global symbol table.
 *
 * @param name The name as an ASCIIZ string.
 * @retval NULL No symbol found.
 * @return rtems_rtl_obj_sym_t* Reference to the symbol.
 */
rtems_rtl_obj_sym_t* rtems_rtl_symbol_global_find (const char* name);

/**
 * Find a symbol given the symbol label in the local object file.
 *
 * @param obj The object file to search.
 * @param name The name as an ASCIIZ string.
 * @retval NULL No symbol found.
 * @return rtems_rtl_obj_sym_t* Reference to the symbol.
 */
rtems_rtl_obj_sym_t* rtems_rtl_symbol_obj_find (rtems_rtl_obj_t* obj,
                                                const char*      name);

/**
 * Add the object file's symbols to the global table.
 *
 * @param obj The object file the symbols are to be added.
 */
void rtems_rtl_symbol_obj_add (rtems_rtl_obj_t* obj);

/**
 * Erase the object file's symbols.
 *
 * @param obj The object file the symbols are to be erased from.
 */
void rtems_rtl_symbol_obj_erase (rtems_rtl_obj_t* obj);

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif