Replacing dtoa library with float64 printing from QuickJS.

Author: xeioex

src/njs_cutils.h

@@ -0,0 +1,154 @@
+/*
+ * Selected C utilities adapted from QuickJS cutils.h
+ *
+ * Copyright (c) 2024 Fabrice Bellard
+ * Copyright (C) NGINX, Inc.
+ */
+
+#ifndef _NJS_CUTILS_H_INCLUDED_
+#define _NJS_CUTILS_H_INCLUDED_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifndef likely
+#define likely(x)       __builtin_expect(!!(x), 1)
+#endif
+
+#ifndef unlikely
+#define unlikely(x)     __builtin_expect(!!(x), 0)
+#endif
+
+#ifndef force_inline
+#define force_inline inline __attribute__((always_inline))
+#endif
+
+#ifndef no_inline
+#define no_inline __attribute__((noinline))
+#endif
+
+/* compatibility attribute used in dtoa implementation */
+#ifndef __maybe_unused
+#define __maybe_unused __attribute__((unused))
+#endif
+
+typedef int BOOL;
+
+#ifndef FALSE
+#define FALSE 0
+#endif
+
+#ifndef TRUE
+#define TRUE 1
+#endif
+
+static inline int
+max_int(int a, int b)
+{
+    return (a > b) ? a : b;
+}
+
+static inline int
+min_int(int a, int b)
+{
+    return (a < b) ? a : b;
+}
+
+static inline uint32_t
+max_uint32(uint32_t a, uint32_t b)
+{
+    return (a > b) ? a : b;
+}
+
+static inline uint32_t
+min_uint32(uint32_t a, uint32_t b)
+{
+    return (a < b) ? a : b;
+}
+
+static inline int64_t
+max_int64(int64_t a, int64_t b)
+{
+    return (a > b) ? a : b;
+}
+
+static inline int64_t
+min_int64(int64_t a, int64_t b)
+{
+    return (a < b) ? a : b;
+}
+
+/* WARNING: undefined if a = 0 */
+static inline int
+clz32(unsigned int a)
+{
+    return __builtin_clz(a);
+}
+
+/* WARNING: undefined if a = 0 */
+static inline int
+clz64(uint64_t a)
+{
+    return __builtin_clzll(a);
+}
+
+/* WARNING: undefined if a = 0 */
+static inline int
+ctz32(unsigned int a)
+{
+    return __builtin_ctz(a);
+}
+
+/* WARNING: undefined if a = 0 */
+static inline int
+ctz64(uint64_t a)
+{
+    return __builtin_ctzll(a);
+}
+
+static inline uint64_t
+float64_as_uint64(double d)
+{
+    union {
+        double   d;
+        uint64_t u64;
+    } u;
+
+    u.d = d;
+    return u.u64;
+}
+
+static inline double
+uint64_as_float64(uint64_t u64)
+{
+    union {
+        double   d;
+        uint64_t u64;
+    } u;
+
+    u.u64 = u64;
+    return u.d;
+}
+
+static inline int
+strstart(const char *str, const char *val, const char **ptr)
+{
+    const char *p = str;
+    const char *q = val;
+
+    while (*q != '\0') {
+        if (*p != *q) {
+            return 0;
+        }
+        p++;
+        q++;
+    }
+
+    if (ptr != NULL) {
+        *ptr = p;
+    }
+
+    return 1;
+}
+
+#endif /* _NJS_CUTILS_H_INCLUDED_ */