Implements C transpiler for unpack function.

c/unpack.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+# define unpack_Nbit_(N)  \
+    static inline void biner_unpack_l##N(int##N##_t* v, uint8_t c, size_t s) {  \
+      assert(s < N/8);  \
+      *v = (*v & (0xff << (s*8))) | (c << (s*8));  \
+    } \
+    static inline void biner_unpack_b##N(int##N##_t* v, uint8_t c, size_t s) {  \
+      assert(s < N/8);  \
+      biner_unpack_l##N(v, c, N/8-s-1);  \
+    }
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+# define unpack_Nbit_(N)  \
+    static inline void biner_unpack_b##N(int##N##_t* v, uint8_t c, size_t s) {  \
+      assert(s < N/8);  \
+      *v = (*v & (0xff << (s*8))) | (c << (s*8));  \
+    } \
+    static inline void biner_unpack_l##N(int##N##_t* v, uint8_t c, size_t s) {  \
+      assert(s < N/8);  \
+      biner_unpack_b##N(v, c, N/8-s-1);  \
+    }
+#else
+# error "byte order unknown"
+#endif
+
+unpack_Nbit_(8);
+unpack_Nbit_(16);
+unpack_Nbit_(32);
+unpack_Nbit_(64);
+
+#undef unpack_Nbit_

c/zone.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define biner_zone_ptr(T) uintptr_t
+
+typedef struct biner_zone_t {
+  uintptr_t tail;
+  size_t    size;
+  uint8_t*  ptr;
+} biner_zone_t;
+
+#define BINER_ZONE_RESERVE 1024
+
+static inline uintptr_t biner_zone_alloc(biner_zone_t* z, size_t sz) {
+  assert(z != NULL);
+  assert(sz > 0);
+
+  if (z->ptr == NULL) {
+    z->ptr = calloc(1, sz);
+    if (z->ptr == NULL) {
+      fprintf(stderr, "malloc failure\n");
+      abort();
+    }
+  }
+  const uintptr_t oldtail = z->tail;
+  z->tail += sz;
+  if (z->tail > z->size) {
+    z->size = z->tail;
+    z->ptr  = realloc(z->ptr, z->size);
+  }
+  memset(z->ptr+oldtail, 0, sz);
+  return oldtail;
+}
+
+static inline uintptr_t biner_zone_strnew(biner_zone_t* z, const char* str) {
+  assert(z != NULL);
+
+  const uintptr_t ret = biner_zone_alloc(z, strlen(str)+1);
+  strcpy((char*) (z->ptr+ret), str);
+  return ret;
+}
+
+static inline void biner_zone_deinitialize(biner_zone_t* z) {
+  assert(z != NULL);
+
+  if (z->ptr != NULL) free(z->ptr);
+}