#include<stdarg.h>
#include<dlfcn.h>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<limits.h>
#include<unistd.h>
#include<lua.h>
#include<lualib.h>
#include<lauxlib.h>
static int lib_initialized = 0;
static int (*orig_open)(const char*, int, mode_t) = 0;
static int (*orig_open64)(const char*, int, mode_t) = 0;
static int (*orig_creat)(const char*, mode_t) = 0;
static lua_State *L = NULL;
void lib_init();
void die(char *fmt, ...) {
va_list args;
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end(args);
fprintf(stderr, "\n");
fflush(stderr);
exit(-1);
}
static char* redirect(const char* file){
int ret;
const char *new;
lua_getglobal(L, "redirect");
lua_pushstring(L, file);
ret = lua_pcall(L, 1, 1, 0);
if(ret){
fprintf(stderr, "取得重定向文件路径时出错了： %s\n", lua_tostring(L, -1));
lua_pop(L, 1);
return (char*)file;
}else{
new = lua_tostring(L, -1);
lua_pop(L, 1);
}
return (char*)new;
}
int open(const char* file, int flags, mode_t mode) {
lib_init();
file = redirect(file);
return orig_open(file, flags, mode);
}
int open64(const char* file, int flags, mode_t mode) {
lib_init();
file = redirect(file);
return orig_open64(file, flags, mode);
}
int creat(const char* file, mode_t mode) {
lib_init();
file = redirect(file);
return orig_creat(file, mode);
}
void lib_init() {
void *libhdl;
char *dlerr;
if (lib_initialized) return;
if (!(libhdl=dlopen("libc.so.6", RTLD_LAZY)))
die("Failed to patch library calls: %s", dlerror());
orig_open = dlsym(libhdl, "open");
if ((dlerr=dlerror()) != NULL)
die("Failed to patch open() library call: %s", dlerr);
orig_open64 = dlsym(libhdl, "open64");
if ((dlerr=dlerror()) != NULL)
die("Failed to patch open64() library call: %s", dlerr);
orig_creat = dlsym(libhdl, "creat");
if ((dlerr=dlerror()) != NULL)
die("Failed to patch creat() library call: %s", dlerr);
int ret;
L = luaL_newstate();
luaL_openlibs(L);
char config[PATH_MAX];
strcpy(config, getenv("HOME"));
strcat(config, "/.openredir.lua");
ret = luaL_dofile(L, config);
if(ret){
die("Error run ~/.openredir.lua");
}
lua_getglobal(L, "redirect");
if(!lua_isfunction(L,-1)){
die("Error run 'redirect' function in openredir.lua");
}
lua_pop(L, 1);
lib_initialized = 1;
}
