include: dix.h: add macros for request handlers and swapping
add some macros for making request handlers easier:
* REQUEST_HEAD_STRUCT() declares a struct and checks size (assuming
length field already had been swapped)
* REQUEST_FIELD_CARD16() swaps a CARD16 (word) if neccessary
* REQUEST_FIELD_CARD32() swaps a CARD32 (dword) if neccessary
How to use them:
1. move swapping of lengths field into the SProc*Dispatch() and drop it
from the individual SProc*()'s
2. put REQUEST_HEAD_STRUCT() ontop of each Proc*()
3. add REQUEST_FIELD_*() below, for all fields to be swapped and
drop their swapping from the SProc*()'s
4. clean up unnecessary wrappers (SProc*()'s just be just call the
corresponding Proc*() by now)
5. let demux SProc just swap length field and call the normal Proc*Dispatch()
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
This commit is contained in:
Enrico Weigelt, metux IT consult
parent
1d9c412683
commit
893f56f6b0
|
|
@ -0,0 +1,257 @@
|
|||
/* SPDX-License-Identifier: MIT OR X11
|
||||
*
|
||||
* Copyright © 2024 Enrico Weigelt, metux IT consult <info@metux.net>
|
||||
*/
|
||||
#ifndef _XSERVER_DIX_REQUEST_PRIV_H
|
||||
#define _XSERVER_DIX_REQUEST_PRIV_H
|
||||
|
||||
#include "dix.h"
|
||||
#include "dixstruct.h"
|
||||
|
||||
/*
|
||||
* byte-swapping macros for request handlers
|
||||
*
|
||||
* need a ClientPtr client field to be defined
|
||||
*
|
||||
* These could be further optimized by using a macro/inline instead of SwapShorts()
|
||||
*/
|
||||
|
||||
#define CLIENT_STRUCT_CARD16_1(buf, a) \
|
||||
do { if (client->swapped) { \
|
||||
cpswaps((buf)->a, (buf)->a); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD16_2(buf, a, b) \
|
||||
do { if (client->swapped) { \
|
||||
cpswaps((buf)->a, (buf)->a); \
|
||||
cpswaps((buf)->b, (buf)->b); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD16_3(buf, a, b, c) \
|
||||
do { if (client->swapped) { \
|
||||
cpswaps((buf)->a, (buf)->a); \
|
||||
cpswaps((buf)->b, (buf)->b); \
|
||||
cpswaps((buf)->c, (buf)->c); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD16_4(buf, a, b, c, d) \
|
||||
do { if (client->swapped) { \
|
||||
cpswaps((buf)->a, (buf)->a); \
|
||||
cpswaps((buf)->b, (buf)->b); \
|
||||
cpswaps((buf)->c, (buf)->c); \
|
||||
cpswaps((buf)->d, (buf)->d); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD16_5(buf, a, b, c, d, e) \
|
||||
do { if (client->swapped) { \
|
||||
cpswaps((buf)->a, (buf)->a); \
|
||||
cpswaps((buf)->b, (buf)->b); \
|
||||
cpswaps((buf)->c, (buf)->c); \
|
||||
cpswaps((buf)->d, (buf)->d); \
|
||||
cpswaps((buf)->e, (buf)->e); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD32_1(buf, a) \
|
||||
do { if (client->swapped) { \
|
||||
cpswapl((buf)->a, (buf)->a); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD32_2(buf, a, b) \
|
||||
do { if (client->swapped) { \
|
||||
cpswapl((buf)->a, (buf)->a); \
|
||||
cpswapl((buf)->b, (buf)->b); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD32_3(buf, a, b, c) \
|
||||
do { if (client->swapped) { \
|
||||
cpswapl((buf)->a, (buf)->a); \
|
||||
cpswapl((buf)->b, (buf)->b); \
|
||||
cpswapl((buf)->c, (buf)->c); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD32_4(buf, a, b, c, d) \
|
||||
do { if (client->swapped) { \
|
||||
cpswapl((buf)->a, (buf)->a); \
|
||||
cpswapl((buf)->b, (buf)->b); \
|
||||
cpswapl((buf)->c, (buf)->c); \
|
||||
cpswapl((buf)->d, (buf)->d); \
|
||||
} } while (0)
|
||||
|
||||
#define CLIENT_STRUCT_CARD32_5(buf, a, b, c, d, e) \
|
||||
do { if (client->swapped) { \
|
||||
cpswapl((buf)->a, (buf)->a); \
|
||||
cpswapl((buf)->b, (buf)->b); \
|
||||
cpswapl((buf)->c, (buf)->c); \
|
||||
cpswapl((buf)->d, (buf)->d); \
|
||||
cpswapl((buf)->e, (buf)->e); \
|
||||
} } while (0)
|
||||
|
||||
/*
|
||||
* macros for request handlers
|
||||
*
|
||||
* these are handling request packet checking and swapping of multi-byte
|
||||
* values, if necessary.
|
||||
*/
|
||||
|
||||
/* declare request struct and check size. length already must have been swapped */
|
||||
#define REQUEST_HEAD_STRUCT(type) \
|
||||
REQUEST(type); \
|
||||
if (stuff == NULL) return (BadLength); \
|
||||
REQUEST_FIELD_CARD16(length); \
|
||||
REQUEST_SIZE_MATCH(type);
|
||||
|
||||
/* declare request struct and check size. length already must have been swapped */
|
||||
#define REQUEST_HEAD_STRUCT_32L(type) \
|
||||
REQUEST(type); \
|
||||
if (stuff == NULL) return (BadLength); \
|
||||
REQUEST_FIELD_CARD32(length); \
|
||||
REQUEST_SIZE_MATCH(type);
|
||||
|
||||
/* declare request struct and check size (at least as big). length already must have been swapped */
|
||||
#define REQUEST_HEAD_AT_LEAST(type) \
|
||||
REQUEST(type); \
|
||||
if (stuff == NULL) return (BadLength); \
|
||||
REQUEST_AT_LEAST_SIZE(type); \
|
||||
REQUEST_FIELD_CARD16(length);
|
||||
|
||||
/* declare request struct, do NOT check size !*/
|
||||
#define REQUEST_HEAD_NO_CHECK(type) \
|
||||
REQUEST(type); \
|
||||
if (stuff == NULL) return (BadLength); \
|
||||
REQUEST_FIELD_CARD16(length);
|
||||
|
||||
/* swap a CARD16 request struct field if necessary */
|
||||
#define REQUEST_FIELD_CARD16(field) \
|
||||
do { if (client->swapped) swaps(&stuff->field); } while (0)
|
||||
|
||||
/* swap a CARD32 request struct field if necessary */
|
||||
#define REQUEST_FIELD_CARD32(field) \
|
||||
do { if (client->swapped) swapl(&stuff->field); } while (0)
|
||||
|
||||
/* swap a CARD64 request struct field if necessary */
|
||||
#define REQUEST_FIELD_CARD64(field) \
|
||||
do { if (client->swapped) swapll(&stuff->field); } while (0)
|
||||
|
||||
/* swap CARD16 rest of request (after the struct) */
|
||||
#define REQUEST_REST_CARD16() \
|
||||
do { if (client->swapped) SwapRestS(stuff); } while (0)
|
||||
|
||||
/* swap CARD32 rest of request (after the struct) */
|
||||
#define REQUEST_REST_CARD32() \
|
||||
do { if (client->swapped) SwapRestL(stuff); } while (0)
|
||||
|
||||
/* swap a buffer of CARD16's */
|
||||
#define REQUEST_BUF_CARD16(buf, count) \
|
||||
do { if (client->swapped) SwapShorts((short*) buf, count); } while (0)
|
||||
|
||||
/* swap a buffer of CARD32's */
|
||||
#define REQUEST_BUF_CARD32(buf, count) \
|
||||
do { if (client->swapped) SwapLongs((CARD32*) buf, count); } while (0)
|
||||
|
||||
/* swap a CARD16 field (if necessary) in reply struct */
|
||||
#define REPLY_FIELD_CARD16(field) \
|
||||
do { if (client->swapped) swaps(&rep.field); } while (0)
|
||||
|
||||
/* swap a CARD32 field (if necessary) in reply struct */
|
||||
#define REPLY_FIELD_CARD32(field) \
|
||||
do { if (client->swapped) swapl(&rep.field); } while (0)
|
||||
|
||||
/* swap a CARD64 field (if necessary) in reply struct */
|
||||
#define REPLY_FIELD_CARD64(field) \
|
||||
do { if (client->swapped) swapll(&rep.field); } while (0)
|
||||
|
||||
/* swap a buffer of CARD16's */
|
||||
#define REPLY_BUF_CARD16(buf, count) \
|
||||
do { if (client->swapped) SwapShorts((short*) buf, count); } while (0)
|
||||
|
||||
/* swap a buffer of CARD32's */
|
||||
#define REPLY_BUF_CARD32(buf, count) \
|
||||
do { if (client->swapped) SwapLongs((CARD32*) buf, count); } while (0)
|
||||
|
||||
/* swap a buffer of CARD64's */
|
||||
#define REPLY_BUF_CARD64(buf, count) \
|
||||
do { if (client->swapped) { \
|
||||
CARD64* ____b = (CARD64*)buf; \
|
||||
for (int ____i=0; ____i<count; ____i++) { \
|
||||
swapll(&____b[____i]); } } } while (0)
|
||||
|
||||
static inline int ClientReplySend(ClientPtr client, xGenericReply *reply, size_t len) {
|
||||
reply->type = X_Reply;
|
||||
reply->sequenceNumber = client->sequence;
|
||||
if (client->swapped) {
|
||||
swaps(&(reply->sequenceNumber));
|
||||
swapl(&(reply->length));
|
||||
}
|
||||
WriteToClient(client, len, reply);
|
||||
return Success;
|
||||
}
|
||||
|
||||
// internal - don't use it anywhere outside this header
|
||||
static inline int __abovezero(int x) {
|
||||
return (x > 0 ? x : 0);
|
||||
}
|
||||
|
||||
/* intentionally having this inline, so the compiler has good chance
|
||||
for optimizations */
|
||||
static inline int ClientReplySendX(ClientPtr client,
|
||||
xGenericReply *reply,
|
||||
size_t len,
|
||||
const void *data1,
|
||||
size_t data1_len,
|
||||
const void *data2,
|
||||
size_t data2_len
|
||||
) {
|
||||
data1_len = __abovezero(data1_len);
|
||||
data2_len = __abovezero(data1_len);
|
||||
reply->length = bytes_to_int32(
|
||||
__abovezero(len + data1_len + data2_len - sizeof(xGenericReply)));
|
||||
reply->type = X_Reply;
|
||||
reply->sequenceNumber = client->sequence;
|
||||
if (client->swapped) {
|
||||
swaps(&(reply->sequenceNumber));
|
||||
swapl(&(reply->length));
|
||||
}
|
||||
WriteToClient(client, len, reply);
|
||||
if (data1_len && data1)
|
||||
WriteToClient(client, data1_len, data1);
|
||||
if (data2_len && data2)
|
||||
WriteToClient(client, data2_len, data2);
|
||||
return Success;
|
||||
}
|
||||
|
||||
#define REPLY_SEND() (ClientReplySend(client, (xGenericReply*)&rep, sizeof(rep)))
|
||||
|
||||
/* send a reply (fix up some fields) and return Success */
|
||||
#define REPLY_SEND_RET_SUCCESS() \
|
||||
do { return REPLY_SEND(); } while (0)
|
||||
|
||||
/* send a reply with extra data - also settings the length field */
|
||||
#define REPLY_SEND_EXTRA(data1, len1) \
|
||||
do { return ClientReplySendX(client, (xGenericReply*)&rep, \
|
||||
sizeof(rep), data1, len1, NULL, 0); \
|
||||
} while (0)
|
||||
|
||||
/* send a reply with extra data - also settings the length field */
|
||||
#define REPLY_SEND_EXTRA_2(data1, len1, data2, len2) \
|
||||
do { return ClientReplySendX(client, (xGenericReply*)&rep, \
|
||||
sizeof(rep), data1, len1, data2, len2); \
|
||||
} while (0)
|
||||
|
||||
/* Declare a SProc*Dispatch function, which swaps the length field
|
||||
(in order to make size check macros work) and then calls the real
|
||||
dispatcher. The swapping of payload fields must be done in the
|
||||
real dispatcher (if necessary) - use REQUEST_FIELD_*() macros there.
|
||||
*/
|
||||
#define DECLARE_SWAPPED_DISPATCH(_name,_dispatch) \
|
||||
static int _X_COLD _name(ClientPtr client) { \
|
||||
REQUEST(xReq); \
|
||||
return _dispatch(client); \
|
||||
}
|
||||
|
||||
#define DECLARE_SWAPPED_DISPATCH_EXTERN(_name,_dispatch) \
|
||||
int _X_COLD _name(ClientPtr client) { \
|
||||
REQUEST(xReq); \
|
||||
return _dispatch(client); \
|
||||
}
|
||||
|
||||
#endif /* _XSERVER_DIX_REQUEST_PRIV_H */
|
||||
Loading…
Reference in New Issue