/** * \addtogroup loader * @{ */ /** * \defgroup elfloader The Contiki ELF loader * * The Contiki ELF loader links, relocates, and loads ELF * (Executable Linkable Format) object files into a running Contiki * system. * * ELF is a standard format for relocatable object code and executable * files. ELF is the standard program format for Linux, Solaris, and * other operating systems. * * An ELF file contains either a standalone executable program or a * program module. The file contains both the program code, the * program data, as well as information about how to link, relocate, * and load the program into a running system. * * The ELF file is composed of a set of sections. The sections contain * program code, data, or relocation information, but can also contain * debugging information. * * To link and relocate an ELF file, the Contiki ELF loader first * parses the ELF file structure to find the appropriate ELF * sections. It then allocates memory for the program code and data in * ROM and RAM, respectively. After allocating memory, the Contiki ELF * loader starts relocating the code found in the ELF file. * * @{ */ /** * \file * Header file for the Contiki ELF loader. * \author * Adam Dunkels <adam@sics.se> * */ /* * Copyright (c) 2005, Swedish Institute of Computer Science * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * This file is part of the Contiki operating system. * */ #ifndef ELFLOADER_H_ #define ELFLOADER_H_ #include "cfs/cfs.h" /** * Return value from elfloader_load() indicating that loading worked. */ #define ELFLOADER_OK 0 /** * Return value from elfloader_load() indicating that the ELF file had * a bad header. */ #define ELFLOADER_BAD_ELF_HEADER 1 /** * Return value from elfloader_load() indicating that no symbol table * could be found in the ELF file. */ #define ELFLOADER_NO_SYMTAB 2 /** * Return value from elfloader_load() indicating that no string table * could be found in the ELF file. */ #define ELFLOADER_NO_STRTAB 3 /** * Return value from elfloader_load() indicating that the size of the * .text segment was zero. */ #define ELFLOADER_NO_TEXT 4 /** * Return value from elfloader_load() indicating that a symbol * specific symbol could not be found. * * If this value is returned from elfloader_load(), the symbol has * been copied into the elfloader_unknown[] array. */ #define ELFLOADER_SYMBOL_NOT_FOUND 5 /** * Return value from elfloader_load() indicating that one of the * required segments (.data, .bss, or .text) could not be found. */ #define ELFLOADER_SEGMENT_NOT_FOUND 6 /** * Return value from elfloader_load() indicating that no starting * point could be found in the loaded module. */ #define ELFLOADER_NO_STARTPOINT 7 /** * elfloader initialization function. * * This function should be called at boot up to initialize the elfloader. */ void elfloader_init(void); /** * \brief Load and relocate an ELF file. * \param fd An open CFS file descriptor. * \return ELFLOADER_OK if loading and relocation worked. * Otherwise an error value. * * This function loads and relocates an ELF file. The ELF * file must have been opened with cfs_open() prior to * calling this function. * * If the function is able to load the ELF file, a pointer * to the process structure in the model is stored in the * elfloader_loaded_process variable. * * \note This function modifies the ELF file opened with cfs_open()! * If the contents of the file is required to be intact, * the file must be backed up first. * */ int elfloader_load(int fd); /** * A pointer to the processes loaded with elfloader_load(). */ extern struct process * const * elfloader_autostart_processes; /** * If elfloader_load() could not find a specific symbol, it is copied * into this array. */ extern char elfloader_unknown[30]; #ifndef ELFLOADER_DATAMEMORY_SIZE #ifdef ELFLOADER_CONF_DATAMEMORY_SIZE #define ELFLOADER_DATAMEMORY_SIZE ELFLOADER_CONF_DATAMEMORY_SIZE #else #define ELFLOADER_DATAMEMORY_SIZE 0x100 #endif #endif /* ELFLOADER_DATAMEMORY_SIZE */ #ifndef ELFLOADER_TEXTMEMORY_SIZE #ifdef ELFLOADER_CONF_TEXTMEMORY_SIZE #define ELFLOADER_TEXTMEMORY_SIZE ELFLOADER_CONF_TEXTMEMORY_SIZE #else #define ELFLOADER_TEXTMEMORY_SIZE 0x100 #endif #endif /* ELFLOADER_TEXTMEMORY_SIZE */ typedef unsigned long elf32_word; typedef signed long elf32_sword; typedef unsigned short elf32_half; typedef unsigned long elf32_off; typedef unsigned long elf32_addr; struct elf32_rela { elf32_addr r_offset; /* Location to be relocated. */ elf32_word r_info; /* Relocation type and symbol index. */ elf32_sword r_addend; /* Addend. */ }; #endif /* ELFLOADER_H_ */ /** @} */ /** @} */