+/*
+ * g_filename_to_utf8
+ *
+ * Converts a string which is in the encoding used for file names by
+ * the C runtime (usually the same as that used by the operating
+ * system) in the current locale into a UTF-8 string.
+ */
+
+gchar *
+g_filename_to_utf8 (const gchar *opsysstring)
+{
+#ifdef G_OS_WIN32
+
+ gint i, clen, wclen, first;
+ const gint len = strlen (opsysstring);
+ wchar_t *wcs, wc;
+ gchar *result, *bp;
+ const wchar_t *wcp;
+
+ wcs = g_new (wchar_t, len);
+ wclen = MultiByteToWideChar (CP_ACP, 0, opsysstring, len, wcs, len);
+
+ wcp = wcs;
+ clen = 0;
+ for (i = 0; i < wclen; i++)
+ {
+ wc = *wcp++;
+
+ if (wc < 0x80)
+ clen += 1;
+ else if (wc < 0x800)
+ clen += 2;
+ else if (wc < 0x10000)
+ clen += 3;
+ else if (wc < 0x200000)
+ clen += 4;
+ else if (wc < 0x4000000)
+ clen += 5;
+ else
+ clen += 6;
+ }
+
+ result = g_malloc (clen + 1);
+
+ wcp = wcs;
+ bp = result;
+ for (i = 0; i < wclen; i++)
+ {
+ wc = *wcp++;
+
+ if (wc < 0x80)
+ {
+ first = 0;
+ clen = 1;
+ }
+ else if (wc < 0x800)
+ {
+ first = 0xc0;
+ clen = 2;
+ }
+ else if (wc < 0x10000)
+ {
+ first = 0xe0;
+ clen = 3;
+ }
+ else if (wc < 0x200000)
+ {
+ first = 0xf0;
+ clen = 4;
+ }
+ else if (wc < 0x4000000)
+ {
+ first = 0xf8;
+ clen = 5;
+ }
+ else
+ {
+ first = 0xfc;
+ clen = 6;
+ }
+
+ /* Woo-hoo! */
+ switch (clen)
+ {
+ case 6: bp[5] = (wc & 0x3f) | 0x80; wc >>= 6; /* Fall through */
+ case 5: bp[4] = (wc & 0x3f) | 0x80; wc >>= 6; /* Fall through */
+ case 4: bp[3] = (wc & 0x3f) | 0x80; wc >>= 6; /* Fall through */
+ case 3: bp[2] = (wc & 0x3f) | 0x80; wc >>= 6; /* Fall through */
+ case 2: bp[1] = (wc & 0x3f) | 0x80; wc >>= 6; /* Fall through */
+ case 1: bp[0] = wc | first;
+ }
+
+ bp += clen;
+ }
+ *bp = 0;
+
+ g_free (wcs);
+
+ return result;
+
+#else
+
+ return g_strdup (opsysstring);
+
+#endif
+}
+
+/*
+ * g_filename_from_utf8
+ *
+ * The reverse of g_filename_to_utf8.
+ */
+
+gchar *
+g_filename_from_utf8 (const gchar *utf8string)
+{
+#ifdef G_OS_WIN32
+
+ gint i, mask, clen, wclen, mblen;
+ const gint len = strlen (utf8string);
+ wchar_t *wcs, *wcp;
+ gchar *result;
+ guchar *cp, *end, c;
+ gint n;
+
+ /* First convert to wide chars */
+ cp = (guchar *) utf8string;
+ end = cp + len;
+ n = 0;
+ wcs = g_new (wchar_t, len + 1);
+ wcp = wcs;
+ while (cp != end)
+ {
+ mask = 0;
+ c = *cp;
+
+ if (c < 0x80)
+ {
+ clen = 1;
+ mask = 0x7f;
+ }
+ else if ((c & 0xe0) == 0xc0)
+ {
+ clen = 2;
+ mask = 0x1f;
+ }
+ else if ((c & 0xf0) == 0xe0)
+ {
+ clen = 3;
+ mask = 0x0f;
+ }
+ else if ((c & 0xf8) == 0xf0)
+ {
+ clen = 4;
+ mask = 0x07;
+ }
+ else if ((c & 0xfc) == 0xf8)
+ {
+ clen = 5;
+ mask = 0x03;
+ }
+ else if ((c & 0xfc) == 0xfc)
+ {
+ clen = 6;
+ mask = 0x01;
+ }
+ else
+ {
+ g_free (wcs);
+ return NULL;
+ }
+
+ if (cp + clen > end)
+ {
+ g_free (wcs);
+ return NULL;
+ }
+
+ *wcp = (cp[0] & mask);
+ for (i = 1; i < clen; i++)
+ {
+ if ((cp[i] & 0xc0) != 0x80)
+ {
+ g_free (wcs);
+ return NULL;
+ }
+ *wcp <<= 6;
+ *wcp |= (cp[i] & 0x3f);
+ }
+
+ cp += clen;
+ wcp++;
+ n++;
+ }
+ if (cp != end)
+ {
+ g_free (wcs);
+ return NULL;
+ }
+
+ /* n is the number of wide chars constructed */
+
+ /* Convert to a string in the current ANSI codepage */
+
+ result = g_new (gchar, 3 * n + 1);
+ mblen = WideCharToMultiByte (CP_ACP, 0, wcs, n, result, 3*n, NULL, NULL);
+ result[mblen] = 0;
+ g_free (wcs);
+
+ return result;
+
+#else
+
+ return g_strdup (utf8string);
+
+#endif
+}
+
+