#include <X11/keysym.h>
#include <X11/Xutil.h>
+#include <X11/extensions/XShm.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
CanonImage *page_images[MAX_PAGES];
int npages;
static unsigned wwidth, wheight;
static int max_relevant_y= -1;
+static XImage *shmim;
+static XShmSegmentInfo shminfo;
+
DEBUG_DEFINE_DEBUGF(pages)
#define xassert(what) \
fatal("YPP client window is implausibly small?");
check_client_window_all_on_screen();
+
+ int shm= XShmQueryExtension(disp);
+ if (shm) {
+ xassert( shmim= XShmCreateImage(disp, attr.visual, attr.depth, ZPixmap,
+ 0,&shminfo, wwidth,wheight) );
+
+ sigset_t oldset, all;
+ sigfillset(&all);
+ sysassert(! sigprocmask(SIG_BLOCK,&all,&oldset) );
+
+ int pfd[2];
+ pid_t cleaner;
+ sysassert(! pipe(pfd) );
+ sysassert( (cleaner= fork()) != -1 );
+ if (!cleaner) {
+ sysassert(! close(pfd[1]) );
+ for (;;) {
+ int r= read(pfd[0], &shminfo.shmid, sizeof(shminfo.shmid));
+ if (!r) exit(0);
+ if (r==sizeof(shminfo.shmid)) break;
+ assert(r==-1 && errno==EINTR);
+ }
+ for (;;) {
+ char bc;
+ int r= read(pfd[0],&bc,1);
+ if (r>=0) break;
+ assert(r==-1 && errno==EINTR);
+ }
+ sysassert(! shmctl(shminfo.shmid,IPC_RMID,0) );
+ exit(0);
+ }
+ sysassert(! close(pfd[0]) );
+
+ sysassert(! sigprocmask(SIG_SETMASK,&oldset,0) );
+
+ assert(shmim->height == wheight);
+ sysassert( (shminfo.shmid=
+ shmget(IPC_PRIVATE, shmim->bytes_per_line * wheight,
+ IPC_CREAT|0600)) >= 0 );
+
+ sysassert( write(pfd[1],&shminfo.shmid,sizeof(shminfo.shmid)) ==
+ sizeof(shminfo.shmid) );
+ sysassert( shminfo.shmaddr= shmat(shminfo.shmid,0,0) );
+ shmim->data= shminfo.shmaddr;
+ shminfo.readOnly= False;
+ xassert( XShmAttach(disp,&shminfo) );
+
+ close(pfd[1]); /* causes IPC_RMID */
+ }
}
static void set_focus(void) {
wait_for_stability(¤t,0,0, "checking current YPP client screen...");
test= convert_page(current);
find_structure(test, &max_relevant_y);
+ check_correct_commodities();
free(test);
/* page to the top - keep pressing page up until the image stops changing */