diff options
| -rw-r--r-- | include/X11/Xlibint.h | 4 | ||||
| -rw-r--r-- | src/xcb_io.c | 17 |
2 files changed, 21 insertions, 0 deletions
diff --git a/include/X11/Xlibint.h b/include/X11/Xlibint.h index 06395b32..d63a5343 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 300ef571..727c6c79 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); +} |