meta: move photon/libc to root

2026-02-08 20:45:25 +00:00
parent f00e74260d
commit 345a37962e
140 changed files with 0 additions and 0 deletions
--- a/libc/stdlib/strtod.c
+++ b/libc/stdlib/strtod.c
@@ -0,0 +1,91 @@
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+double strtod(const char *str, char **ptr)
+{
+    if (ptr == (char **)0) {
+        return atof(str);
+    }
+
+    size_t len = strlen(str);
+    char rstr[len + 1];
+    strcpy(rstr, str);
+
+    char *p = rstr;
+
+    while (isspace(*p)) {
+        ++p;
+    }
+
+    if (*p == '+' || *p == '-') {
+        ++p;
+    }
+
+    if ((p[0] == 'i' || p[0] == 'I')
+            && (p[1] == 'n' || p[1] == 'N')
+            && (p[2] == 'f' || p[2] == 'F')) {
+        if ((p[3] == 'i' || p[3] == 'I')
+                && (p[4] == 'n' || p[4] == 'N')
+                && (p[5] == 'i' || p[5] == 'I')
+                && (p[6] == 't' || p[6] == 'T')
+                && (p[7] == 'y' || p[7] == 'Y')) {
+            *ptr = p + 8;
+            return atof(str);
+        } else {
+            *ptr = p + 3;
+            return atof(str);
+        }
+    }
+
+    if ((p[0] == 'n' || p[0] == 'N')
+            && (p[1] == 'a' || p[1] == 'A')
+            && (p[2] == 'n' || p[2] == 'N')) {
+        p += 3;
+        if (*p == '(') {
+            ++p;
+            while (*p != '\0' && *p != ')') {
+                ++p;
+            }
+
+            if (*p == ')') {
+                ++p;
+            }
+        }
+
+        *ptr = p;
+        return atof(str);
+    }
+
+    if (isdigit(*p) || *p == '.') {
+        int got_dot = 0;
+        while (isdigit(*p) || (!got_dot && *p == '.')) {
+            if (*p == '.')
+                got_dot = 1;
+            ++p;
+        }
+
+        if (*p == 'e' || *p == 'E') {
+            int i;
+            i = 1;
+            if (p[i] == '+' || p[i] == '-') {
+                ++i;
+            }
+
+            if (isdigit (p[i])) {
+                while (isdigit (p[i])) {
+                    ++i;
+                }
+
+                *ptr = p + i;
+                return atof(str);
+            }
+        }
+
+        *ptr = p;
+        return atof(str);
+    }
+
+    *ptr = (char *)str;
+    return 0.0;
+}