rtems/rtl/rtl-sym.h

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /*
0004  *  COPYRIGHT (c) 2012-2014, 2018 Chris Johns <chrisj@rtems.org>
0005  *
0006  * Redistribution and use in source and binary forms, with or without
0007  * modification, are permitted provided that the following conditions
0008  * are met:
0009  * 1. Redistributions of source code must retain the above copyright
0010  *    notice, this list of conditions and the following disclaimer.
0011  * 2. Redistributions in binary form must reproduce the above copyright
0012  *    notice, this list of conditions and the following disclaimer in the
0013  *    documentation and/or other materials provided with the distribution.
0014  *
0015  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0016  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0017  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0018  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0019  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0020  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0021  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0024  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0025  * POSSIBILITY OF SUCH DAMAGE.
0026  */
0027 /**
0028  * @file
0029  *
0030  * @ingroup rtems_rtl
0031  *
0032  * @brief RTEMS Run-Time Linker Object File Symbol Table.
0033  */
0034
0035 #if !defined (_RTEMS_RTL_SYM_H_)
0036 #define _RTEMS_RTL_SYM_H_
0037
0038 #include <rtems.h>
0039 #include "rtl-obj-fwd.h"
0040
0041 #ifdef __cplusplus
0042 extern "C" {
0043 #endif /* __cplusplus */
0044
0045 /**
0046  * An object file symbol.
0047  */
0048 typedef struct rtems_rtl_obj_sym
0049 {
0050   rtems_chain_node node;    /**< The node's link in the chain. */
0051   const char*      name;    /**< The symbol's name. */
0052   void*            value;   /**< The value of the symbol. */
0053   uint32_t         data;    /**< Format specific data. */
0054 } rtems_rtl_obj_sym;
0055
0056 /**
0057  * Table of symbols stored in a hash table.
0058  */
0059 typedef struct rtems_rtl_symbols
0060 {
0061   rtems_chain_control* buckets;
0062   size_t               nbuckets;
0063 } rtems_rtl_symbols;
0064
0065 /**
0066  * A TLS variable offset call. There is one per base image TLS
0067  * variable.
0068  */
0069 typedef size_t (*rtems_rtl_tls_offset_func)(void);
0070
0071 /**
0072  * A TLS symbol offset entry. It is used with an exported symbol table
0073  * to find a TSL table offset for a variable at runtime.
0074  */
0075 typedef struct rtems_rtl_tls_offset
0076 {
0077   size_t                    index;  /** exported symbol table index */
0078   rtems_rtl_tls_offset_func offset; /** TLS offset function */
0079 } rtems_rtl_tls_offset;
0080
0081 /**
0082  * Open a symbol table with the specified number of buckets.
0083  *
0084  * @param symbols The symbol table to open.
0085  * @param buckets The number of buckets in the hash table.
0086  * @retval true The symbol is open.
0087  * @retval false The symbol table could not created. The RTL
0088  *               error has the error.
0089  */
0090 bool rtems_rtl_symbol_table_open (rtems_rtl_symbols* symbols,
0091                                   size_t             buckets);
0092
0093 /**
0094  * Close the table and erase the hash table.
0095  *
0096  * @param symbols Close the symbol table.
0097  */
0098 void rtems_rtl_symbol_table_close (rtems_rtl_symbols* symbols);
0099
0100 /**
0101  * Add a table of exported symbols to the symbol table.
0102  *
0103  * The export table is a series of symbol records and each record has two
0104  * fields:
0105  *
0106  *  1. label
0107  *  2. address
0108  *
0109  * The 'label' is an ASCIIZ string of variable length. The address is of size
0110  * of an unsigned long for the target running the link editor. The byte order
0111  * is defined by the machine type because the table should be built by the
0112  * target compiler.
0113  *
0114  * The table is terminated with a nul string followed by the bytes 0xDE, 0xAD,
0115  * 0xBE, and 0xEF. This avoids alignments issues.
0116  *
0117  * @param obj The object table the symbols are for.
0118  * @param esyms The exported symbol table.
0119  * @param size The size of the table in bytes.
0120  * @param tls_offsets The TLS offsets table. If NULL none provided.
0121  * @param tls_size The number TLS offset entries in the table.
0122  */
0123 bool rtems_rtl_symbol_global_add (rtems_rtl_obj*              obj,
0124                                   const unsigned char*        esyms,
0125                                   unsigned int                size,
0126                                   const rtems_rtl_tls_offset* tls_offsets,
0127                                   unsigned int                tls_size);
0128
0129 /**
0130  * Find a symbol given the symbol label in the global symbol table.
0131  *
0132  * @param name The name as an ASCIIZ string.
0133  * @retval NULL No symbol found.
0134  * @return rtems_rtl_obj_sym* Reference to the symbol.
0135  */
0136 rtems_rtl_obj_sym* rtems_rtl_symbol_global_find (const char* name);
0137
0138 /**
0139  * Sort an object file's local and global symbol table. This needs to
0140  * be done before calling @ref rtems_rtl_symbol_obj_find as it
0141  * performs a binary search on the tables.
0142  *
0143  * @param obj The object file to sort.
0144  */
0145 void rtems_rtl_symbol_obj_sort (rtems_rtl_obj* obj);
0146
0147 /**
0148  * Find a symbol given the symbol label in the local object file.
0149  *
0150  * @param obj The object file to search.
0151  * @param name The name as an ASCIIZ string.
0152  * @retval NULL No symbol found.
0153  * @return rtems_rtl_obj_sym* Reference to the symbol.
0154  */
0155 rtems_rtl_obj_sym* rtems_rtl_symbol_obj_find (rtems_rtl_obj* obj,
0156                                               const char*    name);
0157
0158 /**
0159  * Add the object file's symbols to the global table.
0160  *
0161  * @param obj The object file the symbols are to be added.
0162  */
0163 void rtems_rtl_symbol_obj_add (rtems_rtl_obj* obj);
0164
0165 /**
0166  * Erase the object file's local symbols.
0167  *
0168  * @param obj The object file the local symbols are to be erased from.
0169  */
0170 void rtems_rtl_symbol_obj_erase_local (rtems_rtl_obj* obj);
0171
0172 /**
0173  * Erase the object file's symbols.
0174  *
0175  * @param obj The object file the symbols are to be erased from.
0176  */
0177 void rtems_rtl_symbol_obj_erase (rtems_rtl_obj* obj);
0178
0179 #ifdef __cplusplus
0180 }
0181 #endif /* __cplusplus */
0182
0183 #endif