Remove notcurses_resize() from the public API

[dankamongmen]

I don't think the user should ever need to call notcurses_resize() themselves, and it can be hidden. We call it in notcurses_render() at the end of the rendering step. Why don't we just call it before the rendering step, instead?

Am I missing something?

If we do hide it, be sure to remove it from all the docs, including the book.

[dankamongmen]

I've removed the indications in the documentation that this needs to be called manually for notcurses_render() to work properly, as I don't see how that's possibly the case.

I think we might want to move the screen geometry resample to the front of notcurses_render(), from the end, for the reasons that initially moved us to add that warning: if notcurses_render() runs thinking that lines are one length, and they are some other, shrinking the window will cause bad problems. Note, however, that this doesn't completely eliminate the problem, due to the inherent raciness of BSD signals...

[dankamongmen]

Removed the note from the book.

[dankamongmen]

I have moved notcurses_resize() into internals, and removed its definition from all headers and docs. notcurses_refresh() now accepts int* restrict y, int* restrict x to return any new geometry, and calls notcurses_resize() internally. chunli, however, crashes sometimes now when I rapidly resize things:

==1872895== Invalid read of size 1
==1872895==    at 0x48635CC: notcurses_rasterize (render.c:884)
==1872895==    by 0x4863F6B: notcurses_refresh (render.c:1061)
==1872895==    by 0x10FDD4: chunli_draw (chunli.c:20)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895==  Address 0x7610330 is 16 bytes after a block of size 86,400 alloc'd
==1872895==    at 0x483677F: malloc (vg_replace_malloc.c:309)
==1872895==    by 0x4863EEA: notcurses_refresh (render.c:1053)
==1872895==    by 0x10FDD4: chunli_draw (chunli.c:20)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895== 
==1872895== Invalid read of size 8
==1872895==    at 0x4860458: cell_double_wide_p (notcurses.h:1052)
==1872895==    by 0x4863600: notcurses_rasterize (render.c:889)
==1872895==    by 0x4863F6B: notcurses_refresh (render.c:1061)
==1872895==    by 0x10FDD4: chunli_draw (chunli.c:20)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895==  Address 0x7370068 is 8 bytes after a block of size 57,600 alloc'd
==1872895==    at 0x48366AF: malloc (vg_replace_malloc.c:308)
==1872895==    by 0x4838DE7: realloc (vg_replace_malloc.c:836)
==1872895==    by 0x48619A0: reshape_shadow_fb (render.c:110)
==1872895==    by 0x4862633: notcurses_render_internal (render.c:469)
==1872895==    by 0x4864031: notcurses_render (render.c:1079)
==1872895==    by 0x118619: demo_render (hud.c:457)
==1872895==    by 0x110087: chunli_draw (chunli.c:41)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895== 
==1872895== Invalid read of size 8
==1872895==    at 0x4860458: cell_double_wide_p (notcurses.h:1052)
==1872895==    by 0x4863C6E: notcurses_rasterize (render.c:1007)
==1872895==    by 0x4863F6B: notcurses_refresh (render.c:1061)
==1872895==    by 0x10FDD4: chunli_draw (chunli.c:20)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895==  Address 0x7370068 is 8 bytes after a block of size 57,600 alloc'd
==1872895==    at 0x48366AF: malloc (vg_replace_malloc.c:308)
==1872895==    by 0x4838DE7: realloc (vg_replace_malloc.c:836)
==1872895==    by 0x48619A0: reshape_shadow_fb (render.c:110)
==1872895==    by 0x4862633: notcurses_render_internal (render.c:469)
==1872895==    by 0x4864031: notcurses_render (render.c:1079)
==1872895==    by 0x118619: demo_render (hud.c:457)
==1872895==    by 0x110087: chunli_draw (chunli.c:41)
==1872895==    by 0x1101D4: chunli_demo (chunli.c:61)
==1872895==    by 0x110C7D: ext_demos (demo.c:220)
==1872895==    by 0x1124FD: main (demo.c:532)
==1872895== 
==1872895== 

[dankamongmen]

The reason for the crash is summarized in this existing comment near the top of notcurses_rasterize():

  // FIXME need to track outer{x,y} (position on screen) and inner{x,y}
  // (position within lastframe/rvec, which is lfdimx-sized)
  for(y = nc->stdscr->absy ; y < nc->stdscr->leny + nc->stdscr->absy ; ++y){

by calling notcurses_resize() at the beginning of notcurses_refresh(), we're changing leny and lenx, and they no longer match lfdimy and lfdimx. I think we would have seen the same behavior before, if someone called notcurses_resize() (following an actual resize event) and then called notcurses_refresh(). this didn't happen with notcurses_resize() followed by notcurses_render() because the latter rerenders first, bringing lfdimx up to sync with lenx etc, before calling notcurses_rasterize().

[dankamongmen]

I think ncplane_resize_internal() just needs to be extending and zeroing out lastframe as it does stdplane, and we'll be good. In fact...I think we could then get rid of lfdimy/lfdimx, since every resize (update of lenx/leny) would be followed by a render...no, nvm, but what we can do is chain resize_shadowfb() to the end of notcurses_resize(), so the stdscr and lastframe get updated at the same time, with the same effect. Yes!

[dankamongmen]

Got it! w00t!

[dankamongmen]

It's gone, and we're good.