Loader
/* $Id$ */
/* Copyright (c) 2010-2021 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS System Loader */
/* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* HOLDER 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. */
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <elf.h>
/* private */
/* prototypes */
static int _error(char const * error1, char const * error2, int ret);
static int _ldd(char const * filename, char const * ldpath);
#undef ELFSIZE
#define ELFSIZE 32
#include "elf.c"
#undef ELFSIZE
#define ELFSIZE 64
#include "elf.c"
static int _usage(void);
/* public */
/* functions */
/* main */
int main(int argc, char * argv[])
{
int ret = 0;
int o;
int i;
char const * ldpath;
while((o = getopt(argc, argv, "")) != -1)
switch(o)
{
default:
return _usage();
}
if(optind == argc)
return _usage();
ldpath = getenv("LD_LIBRARY_PATH");
for(i = optind; i < argc; i++)
ret |= _ldd(argv[i], ldpath);
return (ret == 0) ? 0 : 2;
}
/* private */
/* functions */
/* ldd */
static int _ldd(char const * filename, char const * ldpath)
{
int ret = 1;
FILE * fp;
union
{
unsigned char e_ident[EI_NIDENT];
Elf32_Ehdr ehdr32;
Elf64_Ehdr ehdr64;
} elf;
if((fp = fopen(filename, "r")) == NULL)
return _error(filename, strerror(errno), 1);
if(fread(&elf, sizeof(elf), 1, fp) == 1)
{
if(memcmp(elf.e_ident, ELFMAG, SELFMAG) != 0)
ret = -_error(filename, "Not an ELF file", 1);
else if(elf.e_ident[EI_CLASS] == ELFCLASS32)
ret = _do_ldd32(filename, fp, &elf.ehdr32, ldpath);
else if(elf.e_ident[EI_CLASS] == ELFCLASS64)
ret = _do_ldd64(filename, fp, &elf.ehdr64, ldpath);
else
ret = -_error(filename, "Could not determine ELF class",
1);
}
else if(ferror(fp) != 0)
ret = -_error(filename, strerror(errno), 1);
else
ret = -_error(filename, "Not an ELF file", 1);
if(fclose(fp) != 0)
ret = -_error(filename, strerror(errno), 1);
return ret;
}
/* error */
static int _error(char const * error1, char const * error2, int ret)
{
fprintf(stderr, "%s: %s%s%s\n", "ldd", error1, (error2 != NULL) ? ": "
: "", (error2 != NULL) ? error2 : "");
return ret;
}
/* usage */
static int _usage(void)
{
fputs("Usage: ldd filename...\n", stderr);
return 1;
}