Import official C23 code examples for Modern C (Jens Gustedt, 2024)HEADupstream-importmain

- Add official C source files, Makefile, c23-fallback.h, and LICENSE
- Update README.md with study mirror notice

1 files changed, 83 insertions, 0 deletions

diff --git a/life.h b/life.h
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+++ b/life.h
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+#include "c23-fallback.h"
+#include <ctype.h>
+#ifndef __STDC_NO_THREADS__
+# include <threads.h>
+#else
+# error This needs C11 threads, aborting.
+#endif
+#include <stdatomic.h>
+
+
+enum { life_maxit = 1ull << 23, };
+
+typedef struct life life;
+struct life {
+  mtx_t mtx;    //< Mutex that protects Mv
+  cnd_t draw;   //< cnd that controls drawing
+  cnd_t acco;   //< cnd that controls accounting
+  cnd_t upda;   //< cnd that controls updating
+
+  void*restrict Mv;            //< bool M[n0][n1];
+  bool (*visited)[life_maxit]; //< Hashing constellations
+
+  // A bunch of parameters that are not subject to change
+  size_t n0;    //< Number of rows
+  size_t n1;    //< Number of columns
+  size_t off0;  //< Start row
+  size_t len0;  //< Number of rows to be handled
+  size_t off1;  //< Start column
+  size_t len1;  //< Number of columns to be handled
+  void* restrict Bv;  //< Unsigned char B[len0][len1];
+
+
+  // Parameters that are updated but that are protected by the mutex
+  size_t iteration;   //< Current iteration
+  size_t accounted;   //< Last accounted iteration
+  size_t drawn;       //< Last drawn iteration
+  size_t last;        //< Last iteration with new state
+  size_t birth9;      //< Number of birth9 calls
+
+  // Parameters that will dynamically be changed by
+  // different threads
+  _Atomic(size_t) constellations; //< Constellations visited
+  _Atomic(size_t) x0;             //< Cursor position, row
+  _Atomic(size_t) x1;             //< Cursor position, column
+  _Atomic(size_t) frames;         //< FPS for display
+  _Atomic(bool)   finished;       //< This game is finished.
+};
+
+inline
+void life_advance(life* L, signed t0, signed t1) {
+  if (t0) {
+    size_t n = L->n0-2;
+    L->x0 = ((L->x0-1)+n+t0)%n + 1;
+  }
+  if (t1) {
+    size_t n = L->n1-2;
+    L->x1 = ((L->x1-1)+n+t1)%n + 1;
+  }
+}
+
+int life_wait(cnd_t*, mtx_t*);
+void life_sleep(double s);
+
+void life_birth9(life*);
+size_t life_update(life*restrict L);
+void life_count(life*restrict L);
+void life_draw(life*);
+void life_draw4(life*);
+void life_account(life*);
+life* life_init(life*, size_t _n, size_t _m, bool[_n][_m]);
+void life_destroy(life* L);
+void life_torus(life*);
+
+#define LIFE_INITIALIZER                        \
+{                                               \
+    .visited = 0,                               \
+    .birth9 = 1,                                \
+    .x0 = 1,                                    \
+    .x1 = 1,                                    \
+    .frames = 20,                               \
+    .finished = false,                          \
+    .constellations = 1,                        \
+}