/* Similar to the classic wtap can_write_encap function.
* This returns 0 if the encap is ok for this file type.
*/
static int
wslua_filehandler_can_write_encap(int encap, void* data)
{
FileHandler fh = (FileHandler)(data);
int retval = WTAP_ERR_UNWRITABLE_ENCAP;
lua_State* L = NULL;
INIT_FILEHANDLER_ROUTINE(can_write_encap,WTAP_ERR_INTERNAL);
lua_pushnumber(L, encap);
switch ( lua_pcall(L,1,1,1) ) {
case 0:
retval = wslua_optboolint(L,-1,WTAP_ERR_UNWRITABLE_ENCAP);
break;
CASE_ERROR("can_write_encap")
}
END_FILEHANDLER_ROUTINE();
/* the retval we got was either a 1 for true, 0 for false, or WTAP_ERR_UNWRITABLE_ENCAP;
but can_write_encap() expects 0 to be true/yes */
if (retval == 1) {
retval = 0;
} else if (retval == 0) {
retval = WTAP_ERR_UNWRITABLE_ENCAP;
}
return retval;
}
/* The classic wtap dump_open function.
* This returns 1 (TRUE) on success.
*/
static int
wslua_filehandler_dump_open(wtap_dumper *wdh, int *err)
{
FileHandler fh = (FileHandler)(wdh->wslua_data);
int retval = 0;
lua_State* L = NULL;
File *fp = NULL;
CaptureInfoConst *fc = NULL;
INIT_FILEHANDLER_ROUTINE(write_open,0);
create_wdh_priv(L, wdh);
fp = push_Wdh(L, wdh);
fc = push_CaptureInfoConst(L,wdh);
/* Reset err */
if (err) {
*err = 0;
}
switch ( lua_pcall(L,2,1,1) ) {
case 0:
retval = wslua_optboolint(L,-1,0);
break;
CASE_ERROR("write_open")
}
END_FILEHANDLER_ROUTINE();
(*fp)->expired = TRUE;
(*fc)->expired = TRUE;
if (retval == 1) {
/* this is our file type - set the routines and settings into wtap */
if (fh->write_ref != LUA_NOREF) {
wdh->subtype_write = wslua_filehandler_dump;
}
else {
g_warning("FileHandler was not set with a write function, even though write_open() returned true");
return 0;
}
/* it's ok to not have a finish routine */
if (fh->write_finish_ref != LUA_NOREF)
wdh->subtype_finish = wslua_filehandler_dump_finish;
else
wdh->subtype_finish = NULL;
}
else {
/* not our file type? */
remove_wdh_priv(L, wdh);
}
return retval;
}
/* The classic wtap read routine. This returns TRUE if it found the next packet,
* else FALSE.
* If it finds a frame/packet, it should set the pseudo-header info (ie, let Lua set it).
* Also Lua needs to set data_offset to the beginning of the line we're returning.
* This will be the seek_off parameter when this frame is re-read.
*/
static gboolean
wslua_filehandler_read(wtap *wth, int *err, gchar **err_info,
gint64 *data_offset)
{
FileHandler fh = (FileHandler)(wth->wslua_data);
int retval = -1;
lua_State* L = NULL;
File *fp = NULL;
CaptureInfo *fc = NULL;
FrameInfo *fi = NULL;
INIT_FILEHANDLER_ROUTINE(read,FALSE);
/* Reset errno */
if (err) {
*err = errno = 0;
}
wth->phdr.opt_comment = NULL;
fp = push_File(L, wth->fh);
fc = push_CaptureInfo(L, wth, FALSE);
fi = push_FrameInfo(L, &wth->phdr, wth->frame_buffer);
switch ( lua_pcall(L,3,1,1) ) {
case 0:
/*
* Return values for FileHandler:read():
* Integer is the number of read bytes.
* Boolean false indicates an error.
* XXX handling of boolean true is not documented. Currently it will
* succeed without advancing data offset. Should it fail instead?
*/
if (lua_type(L, -1) == LUA_TNUMBER) {
*data_offset = wslua_togint64(L, -1);
retval = 1;
break;
}
retval = wslua_optboolint(L,-1,0);
break;
CASE_ERROR_ERRINFO("read")
}
END_FILEHANDLER_ROUTINE();
(*fp)->expired = TRUE;
(*fc)->expired = TRUE;
(*fi)->expired = TRUE;
lua_settop(L,0);
return (retval == 1);
}
/* Classic wtap seek_read function, called by wtap core. This must return TRUE on
* success, FALSE on error.
*/
static gboolean
wslua_filehandler_seek_read(wtap *wth, gint64 seek_off,
struct wtap_pkthdr *phdr, Buffer *buf,
int *err, gchar **err_info)
{
FileHandler fh = (FileHandler)(wth->wslua_data);
int retval = -1;
lua_State* L = NULL;
File *fp = NULL;
CaptureInfo *fc = NULL;
FrameInfo *fi = NULL;
INIT_FILEHANDLER_ROUTINE(seek_read,FALSE);
/* Reset errno */
if (err) {
*err = errno = 0;
}
phdr->opt_comment = NULL;
fp = push_File(L, wth->random_fh);
fc = push_CaptureInfo(L, wth, FALSE);
fi = push_FrameInfo(L, phdr, buf);
lua_pushnumber(L, (lua_Number)seek_off);
switch ( lua_pcall(L,4,1,1) ) {
case 0:
if (lua_isstring(L,-1)) {
size_t len = 0;
const gchar* fd = lua_tolstring(L, -1, &len);
if (len < WTAP_MAX_PACKET_SIZE)
memcpy(ws_buffer_start_ptr(buf), fd, len);
retval = 1;
break;
}
retval = wslua_optboolint(L,-1,0);
break;
CASE_ERROR_ERRINFO("seek_read")
}
END_FILEHANDLER_ROUTINE();
(*fp)->expired = TRUE;
(*fc)->expired = TRUE;
(*fi)->expired = TRUE;
lua_settop(L,0);
return (retval == 1);
}
/* The classic wtap read routine. This returns TRUE if it found the next packet,
* else FALSE.
* If it finds a frame/packet, it should set the pseudo-header info (ie, let Lua set it).
* Also Lua needs to set data_offset to the beginning of the line we're returning.
* This will be the seek_off parameter when this frame is re-read.
*/
static gboolean
wslua_filehandler_read(wtap *wth, int *err, gchar **err_info,
gint64 *data_offset)
{
FileHandler fh = (FileHandler)(wth->wslua_data);
int retval = -1;
lua_State* L = NULL;
File *fp = NULL;
CaptureInfo *fc = NULL;
FrameInfo *fi = NULL;
INIT_FILEHANDLER_ROUTINE(read,FALSE);
/* Reset errno */
if (err) {
*err = errno = 0;
}
wth->phdr.opt_comment = NULL;
fp = push_File(L, wth->fh);
fc = push_CaptureInfo(L, wth, FALSE);
fi = push_FrameInfo(L, &wth->phdr, wth->frame_buffer);
switch ( lua_pcall(L,3,1,1) ) {
case 0:
if (lua_isnumber(L,-1)) {
*data_offset = wslua_togint64(L, -1);
retval = 1;
break;
}
retval = wslua_optboolint(L,-1,0);
break;
CASE_ERROR_ERRINFO("read")
}
END_FILEHANDLER_ROUTINE();
(*fp)->expired = TRUE;
(*fc)->expired = TRUE;
(*fi)->expired = TRUE;
lua_settop(L,0);
return (retval == 1);
}
/* This is our one-and-only open routine for file handling. When called by
* file_access.c, the wtap wth argument has a void* wslua_data that holds the specific
* FileHandler for the specific registered file format reader. It has this because
* we passed it in when we registered the open routine.
* The open_file_* routines should return:
* -1 on an I/O error;
* 1 if the file they're reading is one of the types it handles;
* 0 if the file they're reading isn't the type they're checking for.
* If the routine handles this type of file, it should set the "file_type"
* field in the "struct wtap" to the type of the file.
*/
static wtap_open_return_val
wslua_filehandler_open(wtap *wth, int *err, gchar **err_info)
{
FileHandler fh = (FileHandler)(wth->wslua_data);
wtap_open_return_val retval = WTAP_OPEN_NOT_MINE;
lua_State* L = NULL;
File *fp = NULL;
CaptureInfo *fc = NULL;
INIT_FILEHANDLER_ROUTINE(read_open,WTAP_OPEN_NOT_MINE);
create_wth_priv(L, wth);
fp = push_File(L, wth->fh);
fc = push_CaptureInfo(L, wth, TRUE);
errno = WTAP_ERR_CANT_OPEN;
switch ( lua_pcall(L,2,1,1) ) {
case 0:
retval = (wtap_open_return_val)wslua_optboolint(L,-1,0);
break;
CASE_ERROR_ERRINFO("read_open")
}
END_FILEHANDLER_ROUTINE();
(*fp)->expired = TRUE;
(*fc)->expired = TRUE;
if (retval == WTAP_OPEN_MINE) {
/* this is our file type - set the routines and settings into wtap */
if (fh->read_ref != LUA_NOREF) {
wth->subtype_read = wslua_filehandler_read;
}
else {
g_warning("Lua file format module lacks a read routine");
return WTAP_OPEN_NOT_MINE;
}
if (fh->seek_read_ref != LUA_NOREF) {
wth->subtype_seek_read = wslua_filehandler_seek_read;
}
else {
g_warning("Lua file format module lacks a seek-read routine");
return WTAP_OPEN_NOT_MINE;
}
/* it's ok to not have a close routine */
if (fh->read_close_ref != LUA_NOREF)
wth->subtype_close = wslua_filehandler_close;
else
wth->subtype_close = NULL;
/* it's ok to not have a sequential close routine */
if (fh->seq_read_close_ref != LUA_NOREF)
wth->subtype_sequential_close = wslua_filehandler_sequential_close;
else
wth->subtype_sequential_close = NULL;
wth->file_type_subtype = fh->file_type;
}
else if (retval == WTAP_OPEN_ERROR) {
/* open error - we *must* return an error code! */
if (err) {
*err = WTAP_ERR_CANT_OPEN;
}
}
else if (retval == WTAP_OPEN_NOT_MINE) {
/* not our file type */
remove_wth_priv(L, wth);
}
else {
/* not a valid return type */
g_warning("FileHandler read_open routine returned %d", retval);
if (err) {
*err = WTAP_ERR_INTERNAL;
}
retval = WTAP_OPEN_ERROR;
}
lua_settop(L,0);
return retval;
}