teliva/src/lfs.c

1125 lines
25 KiB
C

/*
** LuaFileSystem
** Copyright Kepler Project 2003 - 2020
** (http://keplerproject.github.io/luafilesystem)
**
** File system manipulation library.
** This library offers these functions:
** lfs.attributes (filepath [, attributename | attributetable])
** lfs.chdir (path)
** lfs.currentdir ()
** lfs.dir (path)
** lfs.link (old, new[, symlink])
** lfs.lock (fh, mode)
** lfs.lock_dir (path)
** lfs.mkdir (path)
** lfs.rmdir (path)
** lfs.setmode (filepath, mode)
** lfs.symlinkattributes (filepath [, attributename])
** lfs.touch (filepath [, atime [, mtime]])
** lfs.unlock (fh)
*/
#ifndef LFS_DO_NOT_USE_LARGE_FILE
#ifndef _WIN32
#ifndef _AIX
#define _FILE_OFFSET_BITS 64 /* Linux, Solaris and HP-UX */
#else
#define _LARGE_FILES 1 /* AIX */
#endif
#endif
#endif
#ifdef _WIN32
#define _WIN32_WINNT 0x600
#endif
#ifndef LFS_DO_NOT_USE_LARGE_FILE
#define _LARGEFILE64_SOURCE
#endif
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <sys/stat.h>
#ifdef _WIN32
#include <direct.h>
#include <windows.h>
#include <io.h>
#include <sys/locking.h>
#ifdef __BORLANDC__
#include <utime.h>
#else
#include <sys/utime.h>
#endif
#include <fcntl.h>
/* MAX_PATH seems to be 260. Seems kind of small. Is there a better one? */
#define LFS_MAXPATHLEN MAX_PATH
#else
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/types.h>
#include <utime.h>
#include <sys/param.h> /* for MAXPATHLEN */
#ifdef MAXPATHLEN
#define LFS_MAXPATHLEN MAXPATHLEN
#else
#include <limits.h> /* for _POSIX_PATH_MAX */
#define LFS_MAXPATHLEN _POSIX_PATH_MAX
#endif
#endif
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
#include "lfs.h"
#define LFS_VERSION "1.8.0"
#define LFS_LIBNAME "lfs"
#if LUA_VERSION_NUM >= 503 /* Lua 5.3+ */
#ifndef luaL_optlong
#define luaL_optlong luaL_optinteger
#endif
#endif
#if LUA_VERSION_NUM >= 502
#define new_lib(L, l) (luaL_newlib(L, l))
#else
#define new_lib(L, l) (lua_newtable(L), luaL_register(L, NULL, l))
#endif
/* Define 'strerror' for systems that do not implement it */
#ifdef NO_STRERROR
#define strerror(_) "System unable to describe the error"
#endif
#define DIR_METATABLE "directory metatable"
typedef struct dir_data {
int closed;
#ifdef _WIN32
intptr_t hFile;
char pattern[MAX_PATH + 1];
#else
DIR *dir;
#endif
} dir_data;
#define LOCK_METATABLE "lock metatable"
#ifdef _WIN32
#ifdef __BORLANDC__
#define lfs_setmode(file, m) (setmode(_fileno(file), m))
#define STAT_STRUCT struct stati64
#else
#define lfs_setmode(file, m) (_setmode(_fileno(file), m))
#define STAT_STRUCT struct _stati64
#endif
#ifndef _S_IFLNK
#define _S_IFLNK 0x400
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode) (mode&_S_IFDIR)
#endif
#ifndef S_ISREG
#define S_ISREG(mode) (mode&_S_IFREG)
#endif
#ifndef S_ISLNK
#define S_ISLNK(mode) (mode&_S_IFLNK)
#endif
#ifndef S_ISSOCK
#define S_ISSOCK(mode) (0)
#endif
#ifndef S_ISFIFO
#define S_ISFIFO(mode) (0)
#endif
#ifndef S_ISCHR
#define S_ISCHR(mode) (mode&_S_IFCHR)
#endif
#ifndef S_ISBLK
#define S_ISBLK(mode) (0)
#endif
#define STAT_FUNC _stati64
#define LSTAT_FUNC lfs_win32_lstat
#else
#define _O_TEXT 0
#define _O_BINARY 0
#define lfs_setmode(file, m) ((void)file, (void)m, 0)
#define STAT_STRUCT struct stat
#define STAT_FUNC stat
extern int lstat(const char * pathname, struct stat * statbuf);
#define LSTAT_FUNC lstat
#endif
#ifdef _WIN32
#define lfs_mkdir _mkdir
#else
#define lfs_mkdir(path) (mkdir((path), \
S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IXOTH))
#endif
#ifdef _WIN32
int lfs_win32_pusherror(lua_State * L)
{
int en = GetLastError();
lua_pushnil(L);
if (en == ERROR_FILE_EXISTS || en == ERROR_SHARING_VIOLATION)
lua_pushstring(L, "File exists");
else
lua_pushstring(L, strerror(en));
return 2;
}
#define TICKS_PER_SECOND 10000000
#define EPOCH_DIFFERENCE 11644473600LL
time_t windowsToUnixTime(FILETIME ft)
{
ULARGE_INTEGER uli;
uli.LowPart = ft.dwLowDateTime;
uli.HighPart = ft.dwHighDateTime;
return (time_t) (uli.QuadPart / TICKS_PER_SECOND - EPOCH_DIFFERENCE);
}
int lfs_win32_lstat(const char *path, STAT_STRUCT * buffer)
{
WIN32_FILE_ATTRIBUTE_DATA win32buffer;
if (GetFileAttributesEx(path, GetFileExInfoStandard, &win32buffer)) {
if (!(win32buffer.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
return STAT_FUNC(path, buffer);
}
buffer->st_mode = _S_IFLNK;
buffer->st_dev = 0;
buffer->st_ino = 0;
buffer->st_nlink = 0;
buffer->st_uid = 0;
buffer->st_gid = 0;
buffer->st_rdev = 0;
buffer->st_atime = windowsToUnixTime(win32buffer.ftLastAccessTime);
buffer->st_mtime = windowsToUnixTime(win32buffer.ftLastWriteTime);
buffer->st_ctime = windowsToUnixTime(win32buffer.ftCreationTime);
buffer->st_size = 0;
return 0;
} else {
return 1;
}
}
#endif
/*
** Utility functions
*/
static int pusherror(lua_State * L, const char *info)
{
lua_pushnil(L);
if (info == NULL)
lua_pushstring(L, strerror(errno));
else
lua_pushfstring(L, "%s: %s", info, strerror(errno));
lua_pushinteger(L, errno);
return 3;
}
static int pushresult(lua_State * L, int res, const char *info)
{
if (res == -1) {
return pusherror(L, info);
} else {
lua_pushboolean(L, 1);
return 1;
}
}
/*
** Check if the given element on the stack is a file and returns it.
*/
static FILE *check_file(lua_State * L, int idx, const char *funcname)
{
#if LUA_VERSION_NUM == 501
FILE **fh = (FILE **) luaL_checkudata(L, idx, "FILE*");
if (*fh == NULL) {
luaL_error(L, "%s: closed file", funcname);
return 0;
} else
return *fh;
#elif LUA_VERSION_NUM >= 502 && LUA_VERSION_NUM <= 504
luaL_Stream *fh = (luaL_Stream *) luaL_checkudata(L, idx, "FILE*");
if (fh->closef == 0 || fh->f == NULL) {
luaL_error(L, "%s: closed file", funcname);
return 0;
} else
return fh->f;
#else
#error unsupported Lua version
#endif
}
/*
**
*/
static int _file_lock(lua_State * L, FILE * fh, const char *mode,
const long start, long len, const char *funcname)
{
int code;
#ifdef _WIN32
/* lkmode valid values are:
LK_LOCK Locks the specified bytes. If the bytes cannot be locked,
the program immediately tries again after 1 second.
If, after 10 attempts, the bytes cannot be locked,
the constant returns an error.
LK_NBLCK Locks the specified bytes. If the bytes cannot be locked,
the constant returns an error.
LK_NBRLCK Same as _LK_NBLCK.
LK_RLCK Same as _LK_LOCK.
LK_UNLCK Unlocks the specified bytes, which must have been
previously locked.
Regions should be locked only briefly and should be unlocked
before closing a file or exiting the program.
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclib/html/_crt__locking.asp
*/
int lkmode;
switch (*mode) {
case 'r':
lkmode = LK_NBLCK;
break;
case 'w':
lkmode = LK_NBLCK;
break;
case 'u':
lkmode = LK_UNLCK;
break;
default:
return luaL_error(L, "%s: invalid mode", funcname);
}
if (!len) {
fseek(fh, 0L, SEEK_END);
len = ftell(fh);
}
fseek(fh, start, SEEK_SET);
#ifdef __BORLANDC__
code = locking(fileno(fh), lkmode, len);
#else
code = _locking(fileno(fh), lkmode, len);
#endif
#else
struct flock f;
switch (*mode) {
case 'w':
f.l_type = F_WRLCK;
break;
case 'r':
f.l_type = F_RDLCK;
break;
case 'u':
f.l_type = F_UNLCK;
break;
default:
return luaL_error(L, "%s: invalid mode", funcname);
}
f.l_whence = SEEK_SET;
f.l_start = (off_t) start;
f.l_len = (off_t) len;
code = fcntl(fileno(fh), F_SETLK, &f);
#endif
return (code != -1);
}
#ifdef _WIN32
typedef struct lfs_Lock {
HANDLE fd;
} lfs_Lock;
static int lfs_lock_dir(lua_State * L)
{
size_t pathl;
HANDLE fd;
lfs_Lock *lock;
char *ln;
const char *lockfile = "/lockfile.lfs";
const char *path = luaL_checklstring(L, 1, &pathl);
ln = (char *) malloc(pathl + strlen(lockfile) + 1);
if (!ln) {
lua_pushnil(L);
lua_pushstring(L, strerror(errno));
return 2;
}
strcpy(ln, path);
strcat(ln, lockfile);
fd = CreateFile(ln, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE, NULL);
free(ln);
if (fd == INVALID_HANDLE_VALUE) {
return lfs_win32_pusherror(L);
}
lock = (lfs_Lock *) lua_newuserdata(L, sizeof(lfs_Lock));
lock->fd = fd;
luaL_getmetatable(L, LOCK_METATABLE);
lua_setmetatable(L, -2);
return 1;
}
static int lfs_unlock_dir(lua_State * L)
{
lfs_Lock *lock = (lfs_Lock *) luaL_checkudata(L, 1, LOCK_METATABLE);
if (lock->fd != INVALID_HANDLE_VALUE) {
CloseHandle(lock->fd);
lock->fd = INVALID_HANDLE_VALUE;
}
return 0;
}
#else
typedef struct lfs_Lock {
char *ln;
} lfs_Lock;
static int lfs_lock_dir(lua_State * L)
{
lfs_Lock *lock;
size_t pathl;
char *ln;
const char *lockfile = "/lockfile.lfs";
const char *path = luaL_checklstring(L, 1, &pathl);
lock = (lfs_Lock *) lua_newuserdata(L, sizeof(lfs_Lock));
ln = (char *) malloc(pathl + strlen(lockfile) + 1);
if (!ln) {
lua_pushnil(L);
lua_pushstring(L, strerror(errno));
return 2;
}
strcpy(ln, path);
strcat(ln, lockfile);
if (symlink("lock", ln) == -1) {
free(ln);
lua_pushnil(L);
lua_pushstring(L, strerror(errno));
return 2;
}
lock->ln = ln;
luaL_getmetatable(L, LOCK_METATABLE);
lua_setmetatable(L, -2);
return 1;
}
static int lfs_unlock_dir(lua_State * L)
{
lfs_Lock *lock = (lfs_Lock *) luaL_checkudata(L, 1, LOCK_METATABLE);
if (lock->ln) {
unlink(lock->ln);
free(lock->ln);
lock->ln = NULL;
}
return 0;
}
#endif
static int lfs_g_setmode(lua_State * L, FILE * f, int arg)
{
static const int mode[] = { _O_BINARY, _O_TEXT };
static const char *const modenames[] = { "binary", "text", NULL };
int op = luaL_checkoption(L, arg, NULL, modenames);
int res = lfs_setmode(f, mode[op]);
if (res != -1) {
int i;
lua_pushboolean(L, 1);
for (i = 0; modenames[i] != NULL; i++) {
if (mode[i] == res) {
lua_pushstring(L, modenames[i]);
return 2;
}
}
lua_pushnil(L);
return 2;
} else {
return pusherror(L, NULL);
}
}
static int lfs_f_setmode(lua_State * L)
{
return lfs_g_setmode(L, check_file(L, 1, "setmode"), 2);
}
/*
** Locks a file.
** @param #1 File handle.
** @param #2 String with lock mode ('w'rite, 'r'ead).
** @param #3 Number with start position (optional).
** @param #4 Number with length (optional).
*/
static int file_lock(lua_State * L)
{
FILE *fh = check_file(L, 1, "lock");
const char *mode = luaL_checkstring(L, 2);
const long start = (long) luaL_optinteger(L, 3, 0);
long len = (long) luaL_optinteger(L, 4, 0);
if (_file_lock(L, fh, mode, start, len, "lock")) {
lua_pushboolean(L, 1);
return 1;
} else {
lua_pushnil(L);
lua_pushfstring(L, "%s", strerror(errno));
return 2;
}
}
/*
** Unlocks a file.
** @param #1 File handle.
** @param #2 Number with start position (optional).
** @param #3 Number with length (optional).
*/
static int file_unlock(lua_State * L)
{
FILE *fh = check_file(L, 1, "unlock");
const long start = (long) luaL_optinteger(L, 2, 0);
long len = (long) luaL_optinteger(L, 3, 0);
if (_file_lock(L, fh, "u", start, len, "unlock")) {
lua_pushboolean(L, 1);
return 1;
} else {
lua_pushnil(L);
lua_pushfstring(L, "%s", strerror(errno));
return 2;
}
}
/*
** Creates a link.
** @param #1 Object to link to.
** @param #2 Name of link.
** @param #3 True if link is symbolic (optional).
*/
static int make_link(lua_State * L)
{
const char *oldpath = luaL_checkstring(L, 1);
const char *newpath = luaL_checkstring(L, 2);
#ifndef _WIN32
return pushresult(L,
(lua_toboolean(L, 3) ? symlink : link) (oldpath,
newpath),
NULL);
#else
int symbolic = lua_toboolean(L, 3);
STAT_STRUCT oldpathinfo;
int is_dir = 0;
if (STAT_FUNC(oldpath, &oldpathinfo) == 0) {
is_dir = S_ISDIR(oldpathinfo.st_mode) != 0;
}
if (!symbolic && is_dir) {
lua_pushnil(L);
lua_pushstring(L,
"hard links to directories are not supported on Windows");
return 2;
}
int result = symbolic ? CreateSymbolicLink(newpath, oldpath, is_dir)
: CreateHardLink(newpath, oldpath, NULL);
if (result) {
return pushresult(L, result, NULL);
} else {
lua_pushnil(L);
lua_pushstring(L, symbolic ? "make_link CreateSymbolicLink() failed"
: "make_link CreateHardLink() failed");
return 2;
}
#endif
}
/*
** Creates a directory.
** @param #1 Directory path.
*/
static int make_dir(lua_State * L)
{
const char *path = luaL_checkstring(L, 1);
return pushresult(L, lfs_mkdir(path), NULL);
}
/*
** Removes a directory.
** @param #1 Directory path.
*/
static int remove_dir(lua_State * L)
{
const char *path = luaL_checkstring(L, 1);
return pushresult(L, rmdir(path), NULL);
}
/*
** Directory iterator
*/
static int dir_iter(lua_State * L)
{
#ifdef _WIN32
struct _finddata_t c_file;
#else
struct dirent *entry;
#endif
dir_data *d = (dir_data *) luaL_checkudata(L, 1, DIR_METATABLE);
luaL_argcheck(L, d->closed == 0, 1, "closed directory");
#ifdef _WIN32
if (d->hFile == 0L) { /* first entry */
if ((d->hFile = _findfirst(d->pattern, &c_file)) == -1L) {
lua_pushnil(L);
lua_pushstring(L, strerror(errno));
d->closed = 1;
return 2;
} else {
lua_pushstring(L, c_file.name);
return 1;
}
} else { /* next entry */
if (_findnext(d->hFile, &c_file) == -1L) {
/* no more entries => close directory */
_findclose(d->hFile);
d->closed = 1;
return 0;
} else {
lua_pushstring(L, c_file.name);
return 1;
}
}
#else
if ((entry = readdir(d->dir)) != NULL) {
lua_pushstring(L, entry->d_name);
return 1;
} else {
/* no more entries => close directory */
closedir(d->dir);
d->closed = 1;
return 0;
}
#endif
}
/*
** Closes directory iterators
*/
static int dir_close(lua_State * L)
{
dir_data *d = (dir_data *) lua_touserdata(L, 1);
#ifdef _WIN32
if (!d->closed && d->hFile) {
_findclose(d->hFile);
}
#else
if (!d->closed && d->dir) {
closedir(d->dir);
}
#endif
d->closed = 1;
return 0;
}
/*
** Factory of directory iterators
*/
static int dir_iter_factory(lua_State * L)
{
const char *path = luaL_checkstring(L, 1);
dir_data *d;
lua_pushcfunction(L, dir_iter);
d = (dir_data *) lua_newuserdata(L, sizeof(dir_data));
luaL_getmetatable(L, DIR_METATABLE);
lua_setmetatable(L, -2);
d->closed = 0;
#ifdef _WIN32
d->hFile = 0L;
if (strlen(path) > MAX_PATH - 2)
luaL_error(L, "path too long: %s", path);
else
sprintf(d->pattern, "%s/*", path);
#else
d->dir = opendir(path);
if (d->dir == NULL)
luaL_error(L, "cannot open %s: %s", path, strerror(errno));
#endif
#if LUA_VERSION_NUM >= 504
lua_pushnil(L);
lua_pushvalue(L, -2);
return 4;
#else
return 2;
#endif
}
/*
** Creates directory metatable.
*/
static int dir_create_meta(lua_State * L)
{
luaL_newmetatable(L, DIR_METATABLE);
/* Method table */
lua_newtable(L);
lua_pushcfunction(L, dir_iter);
lua_setfield(L, -2, "next");
lua_pushcfunction(L, dir_close);
lua_setfield(L, -2, "close");
/* Metamethods */
lua_setfield(L, -2, "__index");
lua_pushcfunction(L, dir_close);
lua_setfield(L, -2, "__gc");
#if LUA_VERSION_NUM >= 504
lua_pushcfunction(L, dir_close);
lua_setfield(L, -2, "__close");
#endif
return 1;
}
/*
** Creates lock metatable.
*/
static int lock_create_meta(lua_State * L)
{
luaL_newmetatable(L, LOCK_METATABLE);
/* Method table */
lua_newtable(L);
lua_pushcfunction(L, lfs_unlock_dir);
lua_setfield(L, -2, "free");
/* Metamethods */
lua_setfield(L, -2, "__index");
lua_pushcfunction(L, lfs_unlock_dir);
lua_setfield(L, -2, "__gc");
return 1;
}
/*
** Convert the inode protection mode to a string.
*/
#ifdef _WIN32
static const char *mode2string(unsigned short mode)
{
#else
static const char *mode2string(mode_t mode)
{
#endif
if (S_ISREG(mode))
return "file";
else if (S_ISDIR(mode))
return "directory";
else if (S_ISLNK(mode))
return "link";
else if (S_ISSOCK(mode))
return "socket";
else if (S_ISFIFO(mode))
return "named pipe";
else if (S_ISCHR(mode))
return "char device";
else if (S_ISBLK(mode))
return "block device";
else
return "other";
}
/*
** Set access time and modification values for a file.
** @param #1 File path.
** @param #2 Access time in seconds, current time is used if missing.
** @param #3 Modification time in seconds, access time is used if missing.
*/
static int file_utime(lua_State * L)
{
const char *file = luaL_checkstring(L, 1);
struct utimbuf utb, *buf;
if (lua_gettop(L) == 1) /* set to current date/time */
buf = NULL;
else {
utb.actime = (time_t) luaL_optnumber(L, 2, 0);
utb.modtime = (time_t) luaL_optinteger(L, 3, utb.actime);
buf = &utb;
}
return pushresult(L, utime(file, buf), NULL);
}
/* inode protection mode */
static void push_st_mode(lua_State * L, STAT_STRUCT * info)
{
lua_pushstring(L, mode2string(info->st_mode));
}
/* device inode resides on */
static void push_st_dev(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_dev);
}
/* inode's number */
static void push_st_ino(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_ino);
}
/* number of hard links to the file */
static void push_st_nlink(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_nlink);
}
/* user-id of owner */
static void push_st_uid(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_uid);
}
/* group-id of owner */
static void push_st_gid(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_gid);
}
/* device type, for special file inode */
static void push_st_rdev(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_rdev);
}
/* time of last access */
static void push_st_atime(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_atime);
}
/* time of last data modification */
static void push_st_mtime(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_mtime);
}
/* time of last file status change */
static void push_st_ctime(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_ctime);
}
/* file size, in bytes */
static void push_st_size(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_size);
}
#ifndef _WIN32
/* blocks allocated for file */
static void push_st_blocks(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_blocks);
}
/* optimal file system I/O blocksize */
static void push_st_blksize(lua_State * L, STAT_STRUCT * info)
{
lua_pushinteger(L, (lua_Integer) info->st_blksize);
}
#endif
/*
** Convert the inode protection mode to a permission list.
*/
#ifdef _WIN32
static const char *perm2string(unsigned short mode)
{
static char perms[10] = "---------";
int i;
for (i = 0; i < 9; i++)
perms[i] = '-';
if (mode & _S_IREAD) {
perms[0] = 'r';
perms[3] = 'r';
perms[6] = 'r';
}
if (mode & _S_IWRITE) {
perms[1] = 'w';
perms[4] = 'w';
perms[7] = 'w';
}
if (mode & _S_IEXEC) {
perms[2] = 'x';
perms[5] = 'x';
perms[8] = 'x';
}
return perms;
}
#else
static const char *perm2string(mode_t mode)
{
static char perms[10] = "---------";
int i;
for (i = 0; i < 9; i++)
perms[i] = '-';
if (mode & S_IRUSR)
perms[0] = 'r';
if (mode & S_IWUSR)
perms[1] = 'w';
if (mode & S_IXUSR)
perms[2] = 'x';
if (mode & S_IRGRP)
perms[3] = 'r';
if (mode & S_IWGRP)
perms[4] = 'w';
if (mode & S_IXGRP)
perms[5] = 'x';
if (mode & S_IROTH)
perms[6] = 'r';
if (mode & S_IWOTH)
perms[7] = 'w';
if (mode & S_IXOTH)
perms[8] = 'x';
return perms;
}
#endif
/* permssions string */
static void push_st_perm(lua_State * L, STAT_STRUCT * info)
{
lua_pushstring(L, perm2string(info->st_mode));
}
typedef void (*_push_function)(lua_State * L, STAT_STRUCT * info);
struct _stat_members {
const char *name;
_push_function push;
};
struct _stat_members members[] = {
{ "mode", push_st_mode },
{ "dev", push_st_dev },
{ "ino", push_st_ino },
{ "nlink", push_st_nlink },
{ "uid", push_st_uid },
{ "gid", push_st_gid },
{ "rdev", push_st_rdev },
{ "access", push_st_atime },
{ "modification", push_st_mtime },
{ "change", push_st_ctime },
{ "size", push_st_size },
{ "permissions", push_st_perm },
#ifndef _WIN32
{ "blocks", push_st_blocks },
{ "blksize", push_st_blksize },
#endif
{ NULL, NULL }
};
/*
** Get file or symbolic link information
*/
static int _file_info_(lua_State * L,
int (*st)(const char *, STAT_STRUCT *))
{
STAT_STRUCT info;
const char *file = luaL_checkstring(L, 1);
int i;
if (st(file, &info)) {
lua_pushnil(L);
lua_pushfstring(L, "cannot obtain information from file '%s': %s",
file, strerror(errno));
lua_pushinteger(L, errno);
return 3;
}
if (lua_isstring(L, 2)) {
const char *member = lua_tostring(L, 2);
for (i = 0; members[i].name; i++) {
if (strcmp(members[i].name, member) == 0) {
/* push member value and return */
members[i].push(L, &info);
return 1;
}
}
/* member not found */
return luaL_error(L, "invalid attribute name '%s'", member);
}
/* creates a table if none is given, removes extra arguments */
lua_settop(L, 2);
if (!lua_istable(L, 2)) {
lua_newtable(L);
}
/* stores all members in table on top of the stack */
for (i = 0; members[i].name; i++) {
lua_pushstring(L, members[i].name);
members[i].push(L, &info);
lua_rawset(L, -3);
}
return 1;
}
/*
** Get file information using stat.
*/
static int file_info(lua_State * L)
{
return _file_info_(L, STAT_FUNC);
}
/*
** Push the symlink target to the top of the stack.
** Assumes the file name is at position 1 of the stack.
** Returns 1 if successful (with the target on top of the stack),
** 0 on failure (with stack unchanged, and errno set).
*/
static int push_link_target(lua_State * L)
{
const char *file = luaL_checkstring(L, 1);
#ifdef _WIN32
HANDLE h = CreateFile(file, GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (h == INVALID_HANDLE_VALUE) {
return lfs_win32_pusherror(L);
}
#endif
char *target = NULL;
int tsize, size = 256; /* size = initial buffer capacity */
int ok = 0;
while (!ok) {
char *target2 = realloc(target, size);
if (!target2) { /* failed to allocate */
break;
}
target = target2;
#ifdef _WIN32
tsize = GetFinalPathNameByHandle(h, target, size, FILE_NAME_OPENED);
#else
tsize = readlink(file, target, size);
#endif
if (tsize < 0) { /* a readlink() error occurred */
break;
}
if (tsize < size) {
#ifdef _WIN32
if (tsize > 4 && strncmp(target, "\\\\?\\", 4) == 0) {
memmove_s(target, tsize - 3, target + 4, tsize - 3);
tsize -= 4;
}
#endif
ok = 1;
break;
}
/* possibly truncated readlink() result, double size and retry */
size *= 2;
}
if (ok) {
target[tsize] = '\0';
lua_pushlstring(L, target, tsize);
}
#ifdef _WIN32
CloseHandle(h);
#endif
free(target);
return ok;
}
/*
** Get symbolic link information using lstat.
*/
static int link_info(lua_State * L)
{
int ret;
if (lua_isstring(L, 2) && (strcmp(lua_tostring(L, 2), "target") == 0)) {
int ok = push_link_target(L);
return ok ? 1 : pusherror(L, "could not obtain link target");
}
ret = _file_info_(L, LSTAT_FUNC);
if (ret == 1 && lua_type(L, -1) == LUA_TTABLE) {
int ok = push_link_target(L);
if (ok) {
lua_setfield(L, -2, "target");
}
}
return ret;
}
/*
** Assumes the table is on top of the stack.
*/
static void set_info(lua_State * L)
{
lua_pushliteral(L, "Copyright (C) 2003-2017 Kepler Project");
lua_setfield(L, -2, "_COPYRIGHT");
lua_pushliteral(L,
"LuaFileSystem is a Lua library developed to complement "
"the set of functions related to file systems offered by "
"the standard Lua distribution");
lua_setfield(L, -2, "_DESCRIPTION");
lua_pushliteral(L, "LuaFileSystem " LFS_VERSION);
lua_setfield(L, -2, "_VERSION");
}
static const struct luaL_Reg fslib[] = {
{ "attributes", file_info },
/* no 'chdir' without sandboxing it */
/* no 'currentdir' without sandboxing it */
{ "dir", dir_iter_factory },
{ "link", make_link },
{ "lock", file_lock },
{ "mkdir", make_dir },
{ "rmdir", remove_dir },
{ "symlinkattributes", link_info },
{ "setmode", lfs_f_setmode },
{ "touch", file_utime },
{ "unlock", file_unlock },
{ "lock_dir", lfs_lock_dir },
{ NULL, NULL },
};
LFS_EXPORT int luaopen_lfs(lua_State * L)
{
dir_create_meta(L);
lock_create_meta(L);
new_lib(L, fslib);
lua_pushvalue(L, -1);
lua_setglobal(L, LFS_LIBNAME);
set_info(L);
return 1;
}