added sources

lib/string_polyfill/stringp.c

@@ -0,0 +1,55 @@
+#include <stringp.h>
+
+char *strcat_(char *dest, const char *src) {
+  int len = strlen(dest);
+  strcpy(dest + len, src);
+  return dest;
+}
+
+char *rawmemchr_(char *s, char c) {
+  int len = strlen(s);
+  return memchr(s, c, len);
+}
+
+char *strpbrk_(char *s1, const char *s2) {
+  if((s1 == NULL) || (s2 == NULL))
+    return NULL;
+
+  while(*s1) {
+    // Return s1 char position if found in s2
+    if(strchr(s2, *s1)) {
+      return s1;
+    } else {
+      s1++;
+    }
+  }
+  return NULL;
+}
+
+char *strtok_(char *s, const char *delim) {
+  static char *olds;
+  char *token;
+
+  if (s == NULL)
+    s = olds;
+
+  // Scan leading delimiters
+  s += strspn(s, delim);
+  if (*s == '\0') {
+    olds = s;
+    return NULL;
+  }
+
+  // Find the end of the token.
+  token = s;
+  s = strpbrk_(token, delim);
+  if (s == NULL)
+    // This token finishes the string.
+    olds = rawmemchr_(token, '\0');
+  else {
+    // Terminate the token and make OLDS point past it.
+    *s = '\0';
+    olds = s + 1;
+  }
+  return token;
+}