Files
m68k-bdm/m68k/flashlib/elf-utils.c
Bernd Mueller adfd70813f initial push
2026-06-17 13:44:30 +02:00

449 lines
10 KiB
C
Executable File

/*
* $Id: elf-utils.c,v 1.2 2008/07/31 01:53:44 cjohns Exp $
*
* Motorola Background Debug Mode Driver
* Copyright (C) 2008 Chris Johns
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
*
* ELF Support for libelf.
*/
#include <fcntl.h>
#include <string.h>
#include <stdint.h>
#include <elf-utils.h>
#if defined (__WIN32__)
#define ELF_OPEN_MODE (O_RDONLY | O_BINARY)
#else
#define ELF_OPEN_MODE (O_RDONLY)
#endif
void
elf_handle_init (elf_handle* handle)
{
memset (handle, 0, sizeof (*handle));
}
int
elf_open (const char* file, elf_handle* handle, elf_output output)
{
if (handle->fd)
{
if (output)
output ("elf-utils: ELF handle already initialised\n");
return 0;
}
if (elf_version (EV_CURRENT) == EV_NONE)
{
if (output)
output ("elf-utils: ELF library initialization failed: %s\n",
elf_errmsg (-1));
return 0;
}
handle->output = output;
if ((handle->fd = open (file, ELF_OPEN_MODE, 0)) < 0)
{
if (handle->output)
output ("elf-utils: open %s failed\n", file);
return 0;
}
if ((handle->elf = elf_begin (handle->fd, ELF_C_READ, NULL)) == NULL)
{
close (handle->fd);
handle->fd = 0;
if (handle->output)
output ("elf-utils: elf_begin failed: %s\n", elf_errmsg (-1));
return 0;
}
handle->file = strdup (file);
handle->ek = elf_kind (handle->elf);
/*
* Check the executable header.
*/
if (gelf_getehdr (handle->elf, &handle->ehdr) == NULL)
{
if (handle->output)
output ("elf-utils: elf_getehdr failed: %s\n", elf_errmsg (-1));
elf_close (handle);
return 0;
}
if (handle->ehdr.e_machine != EM_68K)
{
if (handle->output)
output ("elf-utils: machine type not Motorola 68000\n");
elf_close (handle);
return 0;
}
if ((handle->ehdr.e_type != ET_REL) && (handle->ehdr.e_type != ET_EXEC))
{
output ("elf-utils: file type no relocable or executable\n");
elf_close (handle);
return 0;
}
if ((handle->eclass = gelf_getclass (handle->elf)) == ELFCLASSNONE)
{
if (handle->output)
output ("elf-utils: elf_getclass failed: %s\n", elf_errmsg (-1));
elf_close (handle);
return 0;
}
/*
* No 64-bit Coldfires yet !
*/
if (handle->eclass != ELFCLASS32)
{
if (handle->output)
output ("elf-utils: ELF 64-bit, only 32-bit support: %s\n",
handle->file);
elf_close (handle);
return 0;
}
if (elf_getshnum (handle->elf, &handle->shnum) == 0)
{
if (handle->output)
output ("elf-utils: elf_getshnum failed: %s\n", elf_errmsg (-1));
elf_close (handle);
return 0;
}
if (elf_getshstrndx (handle->elf, &handle->shstrndx) == 0)
{
if (handle->output)
output ("elf-utils: elf_getshstrndx failed: %s\n", elf_errmsg (-1));
elf_close (handle);
return 0;
}
if (elf_getphnum (handle->elf, &handle->phnum) == 0)
{
if (handle->output)
output ("elf-utils: elf_getphnum failed: %s\n", elf_errmsg (-1));
elf_close (handle);
return 0;
}
return 1;
}
int
elf_close (elf_handle* handle)
{
if (!handle->fd)
return 0;
elf_end (handle->elf);
close (handle->fd);
free (handle->file);
handle->elf = NULL;
handle->file = NULL;
handle->fd = 0;
return 1;
}
int
elf_has_symbol_table (elf_handle* handle)
{
Elf_Scn* section = NULL;
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
GElf_Shdr shdr;
if (gelf_getshdr (section, &shdr) != &shdr)
{
if (shdr.sh_type == SHT_SYMTAB)
{
Elf_Data* data = NULL;
data = elf_getdata (section, data);
if ((data == NULL) || (data->d_size == 0))
return 0;
return 1;
}
}
}
return 0;
}
int
elf_get_symbol (elf_handle* handle, const char* label, GElf_Sym* sym)
{
Elf_Scn* section = NULL;
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
GElf_Shdr shdr;
if (gelf_getshdr (section, &shdr) == &shdr)
{
if (shdr.sh_type == SHT_SYMTAB)
{
Elf_Data* data = NULL;
int symbol = 0;
char* name;
data = elf_getdata (section, data);
if ((data == NULL) || (data->d_size == 0))
return 0;
while (gelf_getsym (data, symbol, sym) == sym)
{
name = elf_strptr (handle->elf,
shdr.sh_link, (size_t) sym->st_name);
if (!name)
{
if (handle->output)
handle->output ("elf-utils: find symbol: %s\n",
elf_errmsg (elf_errno ()));
return 0;
}
if (strcmp (label, name) == 0)
return 1;
symbol++;
}
}
}
}
return 0;
}
int
elf_get_section_hdr (elf_handle* handle, int secindex, GElf_Shdr* shdr)
{
Elf_Scn* section = NULL;
int count = 1;
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
if (count == secindex)
{
if (gelf_getshdr (section, shdr) == shdr)
{
return 1;
}
}
count++;
}
return 0;
}
void*
elf_get_section_data (elf_handle* handle, int secindex, uint32_t* size)
{
Elf_Scn* section = NULL;
int count = 1;
*size = 0;
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
if (count == secindex)
{
Elf_Data* data = NULL;
void* buffer;
data = elf_getdata (section, data);
if (data == NULL)
return NULL;
*size = (uint32_t) data->d_size;
return data->d_buf;
}
count++;
}
return 0;
}
void*
elf_get_section_data_sym (elf_handle* handle, const char* label)
{
GElf_Sym esym;
if (elf_get_symbol (handle, label, &esym))
{
Elf_Scn* section = NULL;
int count = 1;
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
if (count == esym.st_shndx)
{
Elf_Data* data = NULL;
data = elf_getdata (section, data);
if ((data == NULL) || (data->d_size == 0))
return NULL;
return ((uint8_t *) data->d_buf) + esym.st_value;
}
count++;
}
}
return NULL;
}
int
elf_map_over_sections (elf_handle* handle, elf_section_handler handler,
const char* sname)
{
/*
* We need to iterate over the sections, and then for each section we decide
* to load, we need to find the program header for that section. we match
* the program header by finding the program header that has the same virtaul
* address range. This yields us with the physical address which is needed
* to know where to load the section on the target. I don't know if this is
* the correct way to do this, if not, please fix.
*/
Elf_Scn* section = NULL;
int count = 1;
size_t num_headers = 0;
if (elf_getphnum (handle->elf, &num_headers) == 0)
{
if (handle->output)
handle->output ("elf-utils: elf_getphnum error\n");
return 0;
}
while ((section = elf_nextscn (handle->elf, section)) != 0)
{
GElf_Shdr shdr;
if (gelf_getshdr (section, &shdr) == &shdr) {
const char* name;
name = elf_strptr (handle->elf, handle->shstrndx, shdr.sh_name);
if (!sname || (strcmp (sname, name) == 0))
{
/*
* Find a LOAD program header in the same virtual address range.
*/
GElf_Addr vaddr = shdr.sh_addr - shdr.sh_offset;
GElf_Phdr phdr;
size_t i;
for (i = 0; i < num_headers; ++i)
{
if (gelf_getphdr (handle->elf, i, &phdr) != &phdr)
{
if (handle->output)
handle->output ("elf-utils: gelf_getphdr error\n");
return 0;
}
if(phdr.p_type == PT_LOAD)
{
if(phdr.p_vaddr <= shdr.sh_addr &&
phdr.p_vaddr + phdr.p_memsz > shdr.sh_addr)
break;
}
}
if(!handler (handle, (i == num_headers) ? 0 : &phdr, &shdr, name, count))
return 0;
}
}
++count;
}
return 1;
}
#define PRINT_FORMAT " %-12s %d\n"
#define PRINT_FORMAT_X " %-12s 0x%x\n"
void
elf_show_exeheader (elf_handle* handle)
{
#define EHDR_PRINT_FIELD(N) do { \
handle->output (PRINT_FORMAT ,#N, (uintmax_t) handle->ehdr.N); \
} while (0)
char* s;
if (!handle->output)
return;
switch (handle->ek)
{
case ELF_K_AR:
s = "ar(1) archive";
break;
case ELF_K_ELF:
s = "elf object";
break;
case ELF_K_NONE:
s = "data";
break;
default:
s = "unrecognized";
}
handle->output ("%s: %s\n", handle->file, s);
EHDR_PRINT_FIELD (e_type);
EHDR_PRINT_FIELD (e_machine);
EHDR_PRINT_FIELD (e_version);
EHDR_PRINT_FIELD (e_entry);
EHDR_PRINT_FIELD (e_phoff);
EHDR_PRINT_FIELD (e_shoff);
EHDR_PRINT_FIELD (e_flags);
EHDR_PRINT_FIELD (e_ehsize);
EHDR_PRINT_FIELD (e_phentsize);
EHDR_PRINT_FIELD (e_shentsize);
handle->output (PRINT_FORMAT, "(shnum)", (uintmax_t) handle->shnum);
handle->output (PRINT_FORMAT, "(shstrndx)", (uintmax_t) handle->shstrndx);
handle->output (PRINT_FORMAT, "(phnum)", (uintmax_t) handle->phnum);
}
void
elf_show_symbol (elf_handle* handle, GElf_Sym* esym)
{
#define ESYM_PRINT_FIELD(N) do { \
handle->output (PRINT_FORMAT_X ,#N, (uintmax_t) esym->N); \
} while (0)
if (!handle->output)
return;
ESYM_PRINT_FIELD (st_name);
ESYM_PRINT_FIELD (st_value);
ESYM_PRINT_FIELD (st_size);
ESYM_PRINT_FIELD (st_info);
ESYM_PRINT_FIELD (st_other);
ESYM_PRINT_FIELD (st_shndx);
}