1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
From 9f5d83706543696fc944c1835a403938c06f2cc5 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Sat, 02 Mar 2013 04:54:24 +0000
Subject: Add _XEatDataWords to discard a given number of 32-bit words of reply data
Matches the units of the length field in X protocol replies, and provides
a single implementation of overflow checking to avoid having to replicate
those checks in every caller.
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Matthieu Herrb <matthieu.herrb@laas.fr>
Upstream-Status: Backport
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
---
diff --git a/include/X11/Xlibint.h b/include/X11/Xlibint.h
index 06395b3..d63a534 100644
--- a/include/X11/Xlibint.h
+++ b/include/X11/Xlibint.h
@@ -855,6 +855,10 @@ extern void _XEatData(
Display* /* dpy */,
unsigned long /* n */
);
+extern void _XEatDataWords(
+ Display* /* dpy */,
+ unsigned long /* n */
+);
extern char *_XAllocScratch(
Display* /* dpy */,
unsigned long /* nbytes */
diff --git a/src/xcb_io.c b/src/xcb_io.c
index 300ef57..727c6c7 100644
--- a/src/xcb_io.c
+++ b/src/xcb_io.c
@@ -19,6 +19,7 @@
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
+#include <limits.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
@@ -757,3 +758,19 @@ void _XEatData(Display *dpy, unsigned long n)
dpy->xcb->reply_consumed += n;
_XFreeReplyData(dpy, False);
}
+
+/*
+ * Read and discard "n" 32-bit words of data
+ * Matches the units of the length field in X protocol replies, and provides
+ * a single implementation of overflow checking to avoid having to replicate
+ * those checks in every caller.
+ */
+void _XEatDataWords(Display *dpy, unsigned long n)
+{
+ if (n < ((INT_MAX - dpy->xcb->reply_consumed) >> 2))
+ dpy->xcb->reply_consumed += (n << 2);
+ else
+ /* Overflow would happen, so just eat the rest of the reply */
+ dpy->xcb->reply_consumed = dpy->xcb->reply_length;
+ _XFreeReplyData(dpy, False);
+}
--
cgit v0.9.0.2-2-gbebe
|