mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-23 22:20:51 +00:00
82 lines
1.9 KiB
C
82 lines
1.9 KiB
C
/*
|
|
* LD_PRELOAD trick to make c3pldrv handle the absolute path to /usr/{bin,lib,share)}.
|
|
* As c3pldrv is a 32 bit executable, /lib will be rewritten to /lib32.
|
|
*
|
|
* Usage:
|
|
* gcc -shared -fPIC -DOUT="$out" preload.c -o preload.so -ldl
|
|
* LD_PRELOAD=$PWD/preload.so ./c3pldrv
|
|
*/
|
|
|
|
#define _GNU_SOURCE
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <dlfcn.h>
|
|
#include <limits.h>
|
|
|
|
#ifndef OUT
|
|
#error Missing OUT define - path to the installation directory.
|
|
#endif
|
|
|
|
typedef void *(*dlopen_func_t)(const char *filename, int flag);
|
|
typedef int (*open_func_t)(const char *pathname, int flags, ...);
|
|
typedef int (*execv_func_t)(const char *path, char *const argv[]);
|
|
|
|
|
|
void *dlopen(const char *filename, int flag)
|
|
{
|
|
dlopen_func_t orig_dlopen;
|
|
const char *new_filename;
|
|
char buffer[PATH_MAX];
|
|
|
|
orig_dlopen = (dlopen_func_t)dlsym(RTLD_NEXT, "dlopen");
|
|
|
|
new_filename = filename;
|
|
if (strncmp("/usr/lib", filename, 8) == 0) {
|
|
snprintf(buffer, PATH_MAX, OUT "/lib32%s", filename+8);
|
|
buffer[PATH_MAX-1] = '\0';
|
|
new_filename = buffer;
|
|
}
|
|
|
|
return orig_dlopen(new_filename, flag);
|
|
}
|
|
|
|
int open(const char *pathname, int flags, ...)
|
|
{
|
|
open_func_t orig_open;
|
|
const char *new_pathname;
|
|
char buffer[PATH_MAX];
|
|
|
|
orig_open = (open_func_t)dlsym(RTLD_NEXT, "open");
|
|
|
|
new_pathname = pathname;
|
|
if (strncmp("/usr/share", pathname, 10) == 0) {
|
|
snprintf(buffer, PATH_MAX, OUT "%s", pathname+4);
|
|
buffer[PATH_MAX-1] = '\0';
|
|
new_pathname = buffer;
|
|
}
|
|
|
|
return orig_open(new_pathname, flags);
|
|
}
|
|
|
|
int execv(const char *path, char *const argv[])
|
|
{
|
|
execv_func_t orig_execv;
|
|
const char *new_path;
|
|
char buffer[PATH_MAX];
|
|
|
|
orig_execv = (execv_func_t)dlsym(RTLD_NEXT, "execv");
|
|
|
|
new_path = path;
|
|
if (strncmp("/usr/bin", path, 8) == 0) {
|
|
snprintf(buffer, PATH_MAX, OUT "%s", path+4);
|
|
buffer[PATH_MAX-1] = '\0';
|
|
new_path = buffer;
|
|
}
|
|
|
|
return orig_execv(new_path, argv);
|
|
}
|
|
|