Merge branch 'master' of ijackson@chiark:things/ypp-sc-tools

diff --cc pctb/pages.c
index 1fba5a64fccc2b6ccbacc952bd9efb29daa86c1f,dfa9108537bbf7b5a9c19d507a443f6caa13851c..56fb4092b8e35650586c35a4ffd18c3b400e1f70
--- 1/pctb/pages.c
--- 2/pctb/pages.c
+++ b/pctb/pages.c
@@@ -37,12 -37,9 +37,13 @@@
  #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;
+ RgbImage *page0_rgbimage;
  
  char *ocean, *pirate;
  
@@@ -314,58 -321,9 +328,58 @@@ static void raise_and_get_details(void
      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) {
+ static void set_focus_commodity(void) {
    int screen= XScreenNumberOfScreen(attr.screen);
  
    progress("taking control of YPP client window...");