/*
* 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.org/license/LICENSE.
*/
/**
* @file
*
* @ingroup rtems_rtl
*
* @brief RTEMS Run-Time Linker Object Support.
*/
#if !defined (_RTEMS_RTL_OBJ_H_)
#define _RTEMS_RTL_OBJ_H_
#include <rtems.h>
#include <rtems/chain.h>
#include <rtems/rtl/rtl-sym.h>
#include <rtems/rtl/rtl-unresolved.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
* Loader format flags.
*/
#define RTEMS_RTL_FMT_ELF (1 << 0)
#define RTEMS_RTL_FMT_COMP (1 << 1)
#define RTEMS_RTL_FMT_PRIVATE (1 << 16)
/**
* Loader format definition.
*/
typedef struct rtems_rtl_loader_format_s
{
/**
* The format label. This can be used to determine and manage
* specific formats.
*/
const char* label;
/**
* The format flags.
*/
uint32_t flags;
} rtems_rtl_loader_format_t;
/**
* The type of the format loader check handler. This handler checks the format
* and if it is detected as suitable it returns true.
*/
typedef bool (*rtems_rtl_loader_check) (rtems_rtl_obj_t* obj, int fd);
/**
* The type of the format loader load handler. This handler loads the specific
* format.
*/
typedef bool (*rtems_rtl_loader_load) (rtems_rtl_obj_t* obj, int fd);
/**
* The type of the format loader unload handler. This handler unloads the
* specific format.
*/
typedef bool (*rtems_rtl_loader_unload) (rtems_rtl_obj_t* obj);
/**
* The type of the format loader signature handler. This handler checks the
* format signature.
*/
typedef rtems_rtl_loader_format_t* (*rtems_rtl_loader_sig) (void);
/**
* Table for supported loadable formats.
*/
typedef struct rtems_rtl_loader_table_s
{
rtems_rtl_loader_check check; /**< The check handler. */
rtems_rtl_loader_load load; /**< The loader. */
rtems_rtl_loader_unload unload; /**< The unloader. */
rtems_rtl_loader_sig signature; /**< The loader's signature. */
} rtems_rtl_loader_table_t;
/**
* Flags for the various section types.
*/
#define RTEMS_RTL_OBJ_SECT_TEXT (1 << 0) /**< Section holds program text. */
#define RTEMS_RTL_OBJ_SECT_CONST (1 << 1) /**< Section holds program text. */
#define RTEMS_RTL_OBJ_SECT_DATA (1 << 2) /**< Section holds program data. */
#define RTEMS_RTL_OBJ_SECT_BSS (1 << 3) /**< Section holds program bss. */
#define RTEMS_RTL_OBJ_SECT_EH (1 << 4) /**< Section holds exception data. */
#define RTEMS_RTL_OBJ_SECT_REL (1 << 5) /**< Section holds relocation records. */
#define RTEMS_RTL_OBJ_SECT_RELA (1 << 6) /**< Section holds relocation addend
* records. */
#define RTEMS_RTL_OBJ_SECT_SYM (1 << 7) /**< Section holds symbols. */
#define RTEMS_RTL_OBJ_SECT_STR (1 << 8) /**< Section holds strings. */
#define RTEMS_RTL_OBJ_SECT_ALLOC (1 << 9) /**< Section allocates runtime memory. */
#define RTEMS_RTL_OBJ_SECT_LOAD (1 << 10) /**< Section is loaded from object file. */
#define RTEMS_RTL_OBJ_SECT_WRITE (1 << 11) /**< Section is writable, ie data. */
#define RTEMS_RTL_OBJ_SECT_EXEC (1 << 12) /**< Section is executable. */
#define RTEMS_RTL_OBJ_SECT_ZERO (1 << 13) /**< Section is preset to zero. */
#define RTEMS_RTL_OBJ_SECT_LINK (1 << 14) /**< Section is link-ordered. */
#define RTEMS_RTL_OBJ_SECT_CTOR (1 << 15) /**< Section contains constructors. */
#define RTEMS_RTL_OBJ_SECT_DTOR (1 << 16) /**< Section contains destructors. */
#define RTEMS_RTL_OBJ_SECT_LOCD (1 << 17) /**< Section has been located. */
/**
* Section types mask.
*/
#define RTEMS_RTL_OBJ_SECT_TYPES (RTEMS_RTL_OBJ_SECT_TEXT | \
RTEMS_RTL_OBJ_SECT_CONST | \
RTEMS_RTL_OBJ_SECT_DATA | \
RTEMS_RTL_OBJ_SECT_BSS | \
RTEMS_RTL_OBJ_SECT_EH)
/**
* An object file is made up of sections and the can be more than
* one of a specific type of sections. All sections and grouped
* together in memory.
*/
struct rtems_rtl_obj_sect_s
{
rtems_chain_node node; /**< The node's link in the chain. */
int section; /**< The section number. */
const char* name; /**< The section's name. */
size_t size; /**< The size of the section in memory. */
off_t offset; /**< Offset into the object file. Relative to
* the start of the object file. */
uint32_t alignment; /**< Alignment of this section. */
int link; /**< Section link field. */
int info; /**< Secfion info field. */
uint32_t flags; /**< The section's flags. */
void* base; /**< The base address of the section in
* memory. */
int load_order; /**< Order we load sections. */
};
/**
* Object file descriptor flags.
*/
#define RTEMS_RTL_OBJ_LOCKED (1 << 0) /**< Lock the object file so it cannot
* be unloaded. */
#define RTEMS_RTL_OBJ_UNRESOLVED (1 << 1) /**< The object file has unresolved
* external symbols. */
/**
* RTL Object. There is one for each object module loaded plus one for the base
* kernel image.
*/
struct rtems_rtl_obj_s
{
rtems_chain_node link; /**< The node's link in the chain. */
uint32_t flags; /**< The status of the object file. */
uint32_t users; /**< References to the object file. */
int format; /**< The format of the object file. */
const char* fname; /**< The file name for the object. */
const char* oname; /**< The object file name. Can be
* relative. */
const char* aname; /**< The archive name containing the
* object. NULL means the object is not
* in a lib */
off_t ooffset; /**< The object offset in the archive. */
size_t fsize; /**< Size of the object file. */
rtems_chain_control sections; /**< The sections of interest in the
* object file. */
rtems_rtl_obj_sym_t* local_table; /**< Local symbol table. */
size_t local_syms; /**< Local symbol count. */
size_t local_size; /**< Local symbol memory usage. */
rtems_rtl_obj_sym_t* global_table; /**< Global symbol table. */
size_t global_syms; /**< Global symbol count. */
size_t global_size; /**< Global symbol memory usage. */
uint32_t unresolved; /**< The number of unresolved relocations. */
void* text_base; /**< The base address of the text section
* in memory. */
size_t text_size; /**< The size of the text section. */
void* const_base; /**< The base address of the const section
* in memory. */
void* eh_base; /**< The base address of the eh section
* in memory. */
size_t eh_size; /**< The size of the eh section. */
void* data_base; /**< The base address of the data section
* in memory. */
void* bss_base; /**< The base address of the bss section
* in memory. */
size_t bss_size; /**< The size of the bss section. */
size_t exec_size; /**< The amount of executable memory
* allocated */
void* entry; /**< The entry point of the module. */
uint32_t checksum; /**< The checksum of the text sections. A
* zero means do not checksum. */
uint32_t* sec_num; /**< The sec nums of each obj. */
uint32_t obj_num; /**< The count of elf files in an rtl obj. */
struct link_map* linkmap; /**< For GDB. */
void* loader; /**< The file details specific to a loader. */
};
/**
* A section handler is called once for each section that needs to be
* processed by this handler.
*
* @param obj The object file's descriptor the section belongs too.
* @param fd The file descriptor of the object file beling loaded.
* @param sect The section the handler is being invoked to handle.
* @param data A user supplied data variable.
* @retval true The operation was successful.
* @retval false The operation failed and the RTL has been set.
*/
typedef bool (*rtems_rtl_obj_sect_handler_t)(rtems_rtl_obj_t* obj,
int fd,
rtems_rtl_obj_sect_t* sect,
void* data);
/**
* Get the file name.
*
* @param obj The object file.
* @return const char* The string.
*/
static inline const char* rtems_rtl_obj_fname (const rtems_rtl_obj_t* obj)
{
return obj->fname;
}
/**
* Is the file name valid ?
*
* @param obj The object file.
* @return bool There is a file name
*/
static inline bool rtems_rtl_obj_fname_valid (const rtems_rtl_obj_t* obj)
{
return obj->fname;
}
/**
* Get the object name.
*
* @param obj The object file.
* @return const char* The string.
*/
static inline const char* rtems_rtl_obj_oname (const rtems_rtl_obj_t* obj)
{
return obj->oname;
}
/**
* Is the object name valid ?
*
* @param obj The object file.
* @return bool There is an object name
*/
static inline bool rtems_rtl_obj_oname_valid (const rtems_rtl_obj_t* obj)
{
return obj->oname;
}
/**
* Get the archive name.
*
* @param obj The object file.
* @return const char* The string.
*/
static inline const char* rtems_rtl_obj_aname (const rtems_rtl_obj_t* obj)
{
return obj->aname;
}
/**
* Is the archive name valid ?
*
* @param obj The object file.
* @return bool There is an archive name
*/
static inline bool rtems_rtl_obj_aname_valid (const rtems_rtl_obj_t* obj)
{
return obj->aname;
}
/**
* Is the address inside the text section?
*
* @param obj The object file.
* @return bool There is an archive name
*/
static inline bool rtems_rtl_obj_text_inside (const rtems_rtl_obj_t* obj,
const void* address)
{
return
(address >= obj->text_base) &&
(address < (obj->text_base + obj->text_size));
}
/**
* Allocate an object structure on the heap.
*
* @retval NULL No memory for the object.
*/
rtems_rtl_obj_t* rtems_rtl_obj_alloc (void);
/**
* Free the object structure and related resources.
*
* @param obj The object file's descriptor to free.
* @retval false The object has dependences.
* @retval true The object has been freed.
*/
bool rtems_rtl_obj_free (rtems_rtl_obj_t* obj);
/**
* Does the object file have unresolved external references ? If it does the
* results of executing code is unpredictable.
*
* @param obj The object file's descriptor.
* @retval true The object file has unresolved externals.
* @retval false The object file has all external references resolved.
*/
bool rtems_rtl_obj_unresolved (rtems_rtl_obj_t* obj);
/**
* Parses a filename and returns newly allocated strings with the archive name,
* object name, and the object's offset
*
* @param name The filename of the object
* @param aname Address of a string pointer that holds the archive name
* @param oname Address of a string pointer that holds the object name
* @param ooffset Address of an int that holds the object offset
* @retval true The parsing was successful
* @retval false The parsing was unsuccessful
*/
bool rtems_rtl_parse_name (const char* name,
const char** aname,
const char** oname,
off_t* ooffset);
/**
* Check of the name matches the object file's object name.
*
* @param obj The object file's descriptor.
* @param name The name to match.
*/
bool rtems_rtl_match_name (rtems_rtl_obj_t* obj, const char* name);
/**
* Find an object file on disk that matches the name. The object descriptor is
* fill in with the various parts of a name. A name can have archive, object
* file and offset components. The search path in the RTL is searched.
*
* @param obj The object file's descriptor.
* @param name The name to locate on disk.
* @retval true The file has been found.
* @retval false The file could not be located. The RTL error has been set.
*/
bool rtems_rtl_obj_find_file (rtems_rtl_obj_t* obj, const char* name);
/**
* Add a section to the object descriptor.
*
* @param obj The object file's descriptor.
* @param section The section's index number.
* @param name The name of the section.
* @param size The size of the section in memory.
* @param offset The offset of the section in the object file.
* @param alignment The alignment of the section in memory.
* @param link The section's link field (from the ELF format).
* @param info The section's info field (from the ELF format).
* @param flags The section's flags.
* @retval true The section has been added.
* @retval false The section has not been added. See the RTL error.
*/
bool rtems_rtl_obj_add_section (rtems_rtl_obj_t* obj,
int section,
const char* name,
size_t size,
off_t offset,
uint32_t alignment,
int link,
int info,
uint32_t flags);
/**
* Erase the object file descriptor's sections.
*
* @param obj The object file's descriptor.
*/
void rtems_rtl_obj_erase_sections (rtems_rtl_obj_t* obj);
/**
* Find the section given a name.
*
* @param obj The object file's descriptor.
* @param name The name of the section to find.
* @retval NULL The section was not found.
* @return rtems_rtl_obj_sect_t* The named section.
*/
rtems_rtl_obj_sect_t* rtems_rtl_obj_find_section (const rtems_rtl_obj_t* obj,
const char* name);
/**
* Find a section given a section's index number.
*
* @param obj The object file's descriptor.
* @param index The section's index to find.
* @retval NULL The section was not found.
* @return rtems_rtl_obj_sect_t* The found section.
*/
rtems_rtl_obj_sect_t* rtems_rtl_obj_find_section_by_index (const rtems_rtl_obj_t* obj,
int index);
/**
* The text section size. Only use once all the sections has been added. It
* includes alignments between sections that are part of the object's text
* area. The consts sections are included in this section.
*
* @param obj The object file's descriptor.
* @return size_t The size of the text area of the object file.
*/
size_t rtems_rtl_obj_text_size (const rtems_rtl_obj_t* obj);
/**
* The text section alignment for the object file. Only use once all the
* sections has been added. The section alignment is the alignment of the first
* text type section loaded the text section.
*
* You can assume the alignment is a positive integral power of 2 if not 0 or
* 1. If 0 or 1 then there is no alignment.
*
* @param obj The object file's descriptor.
* @return uint32_t The alignment. Can be 0 or 1 for not aligned or the alignment.
*/
uint32_t rtems_rtl_obj_text_alignment (const rtems_rtl_obj_t* obj);
/**
* The const section size. Only use once all the sections has been added. It
* includes alignments between sections that are part of the object's const
* area. The consts sections are included in this section.
*
* @param obj The object file's descriptor.
* @return size_t The size of the const area of the object file.
*/
size_t rtems_rtl_obj_const_size (const rtems_rtl_obj_t* obj);
/**
* The const section alignment for the object file. Only use once all the
* sections has been added. The section alignment is the alignment of the first
* const type section loaded the const section.
*
* You can assume the alignment is a positive integral power of 2 if not 0 or
* 1. If 0 or 1 then there is no alignment.
*
* @param obj The object file's descriptor.
* @return uint32_t The alignment. Can be 0 or 1 for not aligned or the alignment.
*/
uint32_t rtems_rtl_obj_const_alignment (const rtems_rtl_obj_t* obj);
/**
* The eh section size. Only use once all the sections has been added. It
* includes alignments between sections that are part of the object's bss area.
*
* @param obj The object file's descriptor.
* @return size_t The size of the bss area of the object file.
*/
size_t rtems_rtl_obj_eh_size (const rtems_rtl_obj_t* obj);
/**
* The eh section alignment for the object file. Only use once all the sections
* has been added. The section alignment is the alignment of the first bss type
* section loaded the bss section.
*
* You can assume the alignment is a positive integral power of 2 if not 0 or
* 1. If 0 or 1 then there is no alignment.
*
* @param obj The object file's descriptor.
* @return uint32_t The alignment. Can be 0 or 1 for not aligned or the alignment.
*/
uint32_t rtems_rtl_obj_eh_alignment (const rtems_rtl_obj_t* obj);
/**
* The data section size. Only use once all the sections has been added. It
* includes alignments between sections that are part of the object's data
* area.
*
* @param obj The object file's descriptor.
* @return size_t The size of the data area of the object file.
*/
size_t rtems_rtl_obj_data_size (const rtems_rtl_obj_t* obj);
/**
* The data section alignment for the object file. Only use once all the
* sections has been added. The section alignment is the alignment of the first
* data type section loaded the data section.
*
* You can assume the alignment is a positive integral power of 2 if not 0 or
* 1. If 0 or 1 then there is no alignment.
*
* @param obj The object file's descriptor.
* @return uint32_t The alignment. Can be 0 or 1 for not aligned or the alignment.
*/
uint32_t rtems_rtl_obj_data_alignment (const rtems_rtl_obj_t* obj);
/**
* The bss section size. Only use once all the sections has been added. It
* includes alignments between sections that are part of the object's bss area.
*
* @param obj The object file's descriptor.
* @return size_t The size of the bss area of the object file.
*/
size_t rtems_rtl_obj_bss_size (const rtems_rtl_obj_t* obj);
/**
* The bss section alignment for the object file. Only use once all the
* sections has been added. The section alignment is the alignment of the first
* bss type section loaded the bss section.
*
* You can assume the alignment is a positive integral power of 2 if not 0 or
* 1. If 0 or 1 then there is no alignment.
*
* @param obj The object file's descriptor.
* @return uint32_t The alignment. Can be 0 or 1 for not aligned or the alignment.
*/
uint32_t rtems_rtl_obj_bss_alignment (const rtems_rtl_obj_t* obj);
/**
* Relocate the object file. The object file's section are parsed for any
* relocation type sections.
*
* @param obj The object file's descriptor.
* @param fd The object file's file descriptor.
* @param handler The object file's format specific relocation handler.
* @param data User specific data handle.
* @retval true The object file was relocated.
* @retval false The relocation failed. The RTL error is set.
*/
bool rtems_rtl_obj_relocate (rtems_rtl_obj_t* obj,
int fd,
rtems_rtl_obj_sect_handler_t handler,
void* data);
/**
* Synchronize caches to make code visible to CPU(s)
*
* @param obj The object file's descriptor.
*/
void rtems_rtl_obj_synchronize_cache (rtems_rtl_obj_t* obj);
/**
* Relocate an object file's unresolved reference.
*
* @param rec The unresolved relocation record.
* @param sym The unresolved relocation's referenced symbol.
* @retval true The object file record was relocated.
* @retval false The relocation failed. The RTL error is set.
*/
bool rtems_rtl_obj_relocate_unresolved (rtems_rtl_unresolv_reloc_t* reloc,
rtems_rtl_obj_sym_t* sym);
/**
* Load the symbols from the object file. Only the exported or public symbols
* are read into memory and held in the global symbol table.
*
* @param obj The object file's descriptor.
* @param fd The object file's file descriptor.
* @param handler The object file's format specific symbol handler.
* @param data User specific data handle.
* @retval true The object file's symbol where loaded.
* @retval false The symbol loading failed. The RTL error is set.
*/
bool rtems_rtl_obj_load_symbols (rtems_rtl_obj_t* obj,
int fd,
rtems_rtl_obj_sect_handler_t handler,
void* data);
/**
* Load the sections that have been allocated memory in the target. The bss
* type section does not load any data, it is set to 0. The text and data
* sections read the detault data from the object file into the target memory.
*
* @param obj The object file's descriptor.
* @param fd The object file's file descriptor.
* @param handler The object file's format specific load handler.
* @param data User specific data handle.
* @retval true The object has been sucessfully loaded.
* @retval false The load failed. The RTL error has been set.
*/
bool rtems_rtl_obj_load_sections (rtems_rtl_obj_t* obj,
int fd,
rtems_rtl_obj_sect_handler_t handler,
void* data);
/**
* Invoke the constructors the object has. Constructors are a table of pointers
* to "void (*)(void);" where NULL pointers are skipped. The table's size is
* taken from the section's size. The objet ELF specific code is responisble
* for flagging which sections contain constructors.
*
* @param obj The object file's descriptor.
*/
void rtems_rtl_obj_run_ctors (rtems_rtl_obj_t* obj);
/**
* Invoke the destructors the object has. Destructors are a table of pointers
* to "void (*)(void);" where NULL pointers are skipped. The table's size is
* taken from the section's size. The objet ELF specific code is responisble
* for flagging which sections contain destructors.
*
* @param obj The object file's descriptor.
*/
void rtems_rtl_obj_run_dtors (rtems_rtl_obj_t* obj);
/**
* Load the object file, reading all sections into memory, symbols and
* performing any relocation fixups.
*
* @param obj The object file's descriptor.
* @retval true The object file has been loaded.
* @retval false The load failed. The RTL error has been set.
*/
bool rtems_rtl_obj_load (rtems_rtl_obj_t* obj);
/**
* Unload the object file, erasing all symbols and releasing all memory.
*
* @param obj The object file's descriptor.
* @retval true The object file has been unloaded.
* @retval false The unload failed. The RTL error has been set.
*/
bool rtems_rtl_obj_unload (rtems_rtl_obj_t* obj);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif
