new file mode 100644
--- /dev/null
+++ b/src/core/ngx_string.h
@@ -0,0 +1,94 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#ifndef _NGX_STRING_H_INCLUDED_
+#define _NGX_STRING_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+typedef struct {
+    size_t    len;
+    u_char   *data;
+} ngx_str_t;
+
+
+#define ngx_string(str)  { sizeof(str) - 1, (u_char *) str }
+#define ngx_null_string  { 0, NULL }
+
+
+#if (WIN32)
+
+#define ngx_strncasecmp(s1, s2, n)                                           \
+                           strnicmp((const char *) s1, (const char *) s2, n)
+#define ngx_strcasecmp(s1, s2)                                               \
+                           stricmp((const char *) s1, (const char *) s2)
+
+#define ngx_snprintf       _snprintf
+#define ngx_vsnprintf      _vsnprintf
+
+#else
+
+#define ngx_strncasecmp(s1, s2, n)                                           \
+                           strncasecmp((const char *) s1, (const char *) s2, n)
+#define ngx_strcasecmp(s1, s2)                                               \
+                           strcasecmp((const char *) s1, (const char *) s2)
+
+#define ngx_snprintf       snprintf
+#define ngx_vsnprintf      vsnprintf
+
+#endif
+
+
+#define ngx_strncmp(s1, s2, n)                                               \
+                            strncmp((const char *) s1, (const char *) s2, n)
+
+/* msvc and icc compile strcmp() to inline loop */
+#define ngx_strcmp(s1, s2)  strcmp((const char *) s1, (const char *) s2)
+
+#define ngx_strstr(s1, s2)  strstr((const char *) s1, (const char *) s2)
+#define ngx_strlen(s)       strlen((const char *) s)
+
+/*
+ * msvc and icc compile memset() to the inline "rep stos"
+ * while ZeroMemory() and bzero() are the calls.
+ * icc may also inline several mov's of a zeroed register for small blocks.
+ */
+#define ngx_memzero(buf, n)       memset(buf, 0, n)
+
+/* msvc and icc compile memcpy() to the inline "rep movs" */
+#define ngx_memcpy(dst, src, n)   memcpy(dst, src, n)
+#define ngx_cpymem(dst, src, n)   ((u_char *) memcpy(dst, src, n)) + n
+
+/* msvc and icc compile memcmp() to the inline loop */
+#define ngx_memcmp                memcmp
+
+u_char *ngx_cpystrn(u_char *dst, u_char *src, size_t n);
+ngx_int_t ngx_rstrncmp(u_char *s1, u_char *s2, size_t n);
+
+ngx_int_t ngx_atoi(u_char *line, size_t n);
+ngx_int_t ngx_hextoi(u_char *line, size_t n);
+
+void ngx_md5_text(u_char *text, u_char *md5);
+
+
+#define ngx_base64_encoded_length(len)  (((len + 2) / 3) * 4)
+#define ngx_base64_decoded_length(len)  (((len + 3) / 4) * 3)
+
+void ngx_encode_base64(ngx_str_t *src, ngx_str_t *dst);
+ngx_int_t ngx_decode_base64(ngx_str_t *src, ngx_str_t *dst);
+
+
+#define  ngx_qsort                qsort
+
+
+#define  ngx_value_helper(n)      #n
+#define  ngx_value(n)             ngx_value_helper(n)
+
+
+#endif /* _NGX_STRING_H_INCLUDED_ */