Clean up more code

The *NSYNC linked list API is good enough that it deserves to be part of
the C libray, so this change writes an improved version of it which uses
that offsetof() trick from the Linux Kernel. We vendor all of the *NSYNC
tests in third_party which helped confirm the needed refactoring is safe

This change also deletes more old code that didn't pan out. My goal here
is to work towards a vision where the Cosmopolitan core libraries become
less experimental and more focused on curation. This better reflects the
current level of quality we've managed to achieve.

tool/viz/lib/boxblur.c

@@ -25,5 +25,5 @@ void boxblur(struct Graphic *g) {
       {+1.0, +1.0, +1.0},
       {+1.0, +1.0, +1.0},
   };
-  convolve(g->yn, g->xn, g->b.p, 3, kBoxBlurKernel, 9.0, 0);
+  convolve(g->yn, g->xn, g->b, 3, kBoxBlurKernel, 9.0, 0);
 }

tool/viz/lib/convolve.h

@@ -1,6 +1,7 @@
 #ifndef COSMOPOLITAN_TOOL_VIZ_LIB_CONVOLVE_H_
 #define COSMOPOLITAN_TOOL_VIZ_LIB_CONVOLVE_H_
 #include "dsp/tty/quant.h"
+#include "libc/mem/mem.h"
 #include "libc/str/str.h"
 #include "tool/viz/lib/graphic.h"
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
@@ -24,7 +25,7 @@ forceinline void convolve(unsigned yn, unsigned xn, ttyrgb_m128 img[yn][xn],
   }
   bzero(&g, sizeof(g));
   resizegraphic(&g, yn, xn);
-  tmp = g.b.p;
+  tmp = g.b;
   for (y = 0; y < yn - KW; ++y) {
     for (x = 0; x < xn - KW; ++x) {
       bzero(&p, sizeof(p));
@@ -37,7 +38,7 @@ forceinline void convolve(unsigned yn, unsigned xn, ttyrgb_m128 img[yn][xn],
     }
   }
   memcpy(img, tmp, yn * xn * sizeof(img[0][0]));
-  bfree(&g.b);
+  free(g.b);
 }
 
 COSMOPOLITAN_C_END_

tool/viz/lib/emboss.c

@@ -26,5 +26,5 @@ void emboss(struct Graphic *g) {
       {-1.0, +1.0, +1.0},
       {+0.0, +1.0, +2.0},
   };
-  convolve(g->yn, g->xn, g->b.p, 3, kEmbossKernel, 1, 0);
+  convolve(g->yn, g->xn, g->b, 3, kEmbossKernel, 1, 0);
 }

tool/viz/lib/getxtermcodes.c

@@ -22,7 +22,7 @@
 
 void getxtermcodes(struct TtyRgb *p, const struct Graphic *g) {
   unsigned y, x;
-  unsigned char(*img)[3][g->yn][g->xn] = g->b.p;
+  unsigned char(*img)[3][g->yn][g->xn] = g->b;
   for (y = 0; y < g->yn; ++y) {
     for (x = 0; x < g->xn; ++x) {
       *p++ = rgb2tty((*img)[0][y][x], (*img)[1][y][x], (*img)[2][y][x]);

tool/viz/lib/graphic.h

@@ -1,13 +1,12 @@
 #ifndef COSMOPOLITAN_TOOL_VIZ_LIB_GRAPHIC_H_
 #define COSMOPOLITAN_TOOL_VIZ_LIB_GRAPHIC_H_
 #include "dsp/tty/quant.h"
-#include "libc/runtime/buffer.internal.h"
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
 COSMOPOLITAN_C_START_
 
 struct Graphic {
   union {
-    struct GuardedBuffer b;
+    void *b;
     char *bytes;
     float (*lum)[2][8];
     float (*rgba)[2][2];

tool/viz/lib/resizegraphic.c

@@ -18,19 +18,14 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "dsp/tty/quant.h"
 #include "libc/assert.h"
-#include "libc/runtime/buffer.internal.h"
+#include "libc/mem/mem.h"
 #include "tool/viz/lib/graphic.h"
 
-/**
- * Allocates graphic.
- *
- * @param g should be zero initialized before first call
- * @note bfree(g->b) needs to be called later
- */
+// TODO(jart): DELETE
+
 struct Graphic *resizegraphic(struct Graphic *g, size_t yn, size_t xn) {
-  /* assert(xn % 2 == 0); */ /* todo: ughhh this whole thing is wrong */
   yn &= ~1;
-  balloc(&g->b, 64, yn * xn * sizeof(ttyrgb_m128) + /* wut */ PAGESIZE);
+  g->b = pvalloc(yn * xn * sizeof(ttyrgb_m128));
   g->yn = yn;
   g->xn = xn;
   return g;

tool/viz/lib/sobel.c

@@ -69,7 +69,7 @@ void sobel(struct Graphic* g) {
            FLIP(BROADCAST(-2), BROADCAST(+0), BROADCAST(+2)),
            FLIP(BROADCAST(-1), BROADCAST(+0), BROADCAST(+1)));
   if (g->yn >= 3 && g->xn >= 3) {
-    ConvolveGradient(g->yn, g->xn, g->b.p, 3, &kSobelEmbossKernelY,
+    ConvolveGradient(g->yn, g->xn, g->b, 3, &kSobelEmbossKernelY,
                      &kSobelEmbossKernelX);
   }
 }

tool/viz/lib/vizlib.mk

@@ -66,8 +66,7 @@ o/$(MODE)/tool/viz/lib/dither.o				\
 o/$(MODE)/tool/viz/lib/emboss.o				\
 o/$(MODE)/tool/viz/lib/getxtermcodes.o			\
 o/$(MODE)/tool/viz/lib/lingamma.o			\
-o/$(MODE)/tool/viz/lib/perlin3.o			\
-o/$(MODE)/tool/viz/lib/resizegraphic.o: private		\
+o/$(MODE)/tool/viz/lib/perlin3.o: private		\
 		CFLAGS +=				\
 			-DSTACK_FRAME_UNLIMITED		\
 			$(MATHEMATICAL)