From a220b385eff24a6218483a4d80a9ed252b1d5b4a Mon Sep 17 00:00:00 2001
From: Owen Shepherd <owen.shepherd@e43.eu>
Date: Tue, 1 Jan 2013 21:08:56 +0000
Subject: [PATCH] PDCLIB-2 PDCLIB-9 mbrtowc

---
 functions/wchar/mbrtowc.c | 95 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644 functions/wchar/mbrtowc.c

diff --git a/functions/wchar/mbrtowc.c b/functions/wchar/mbrtowc.c
new file mode 100644
index 0000000..610f828
--- /dev/null
+++ b/functions/wchar/mbrtowc.c
@@ -0,0 +1,95 @@
+/* mbrtowc(
+    wchar_t *restrict pwc, 
+    const char *restrict s, 
+    size_t n, 
+    mbstate_t *restrict ps);
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <wchar.h>
+#ifndef REGTEST
+#include <errno.h>
+#include <stdint.h>
+#include <assert.h>
+#include <_PDCLIB_encoding.h>
+#include <_PDCLIB_locale.h>
+
+size_t mbrtowc_l(
+    wchar_t    *restrict    pwc, 
+    const char *restrict    s, 
+    size_t                  n, 
+    mbstate_t  *restrict    ps,
+    locale_t    restrict    l
+)
+{
+    size_t res;
+
+    if(s == NULL) {
+        s = "";
+        n = 1;
+    }
+
+    if(ps->_PendState == _PendPrefix) {
+        res = _PDCLIB_mbrtocwc_l(pwc, &ps->_PendChar, 1, ps, l);
+        switch(res) {
+            case 0:
+                // Converted the NUL character
+                ps->_PendState = _PendClear;
+                return 0;
+
+            case 1:
+                // Successful conversion
+                ps->_PendChar = *s;
+                return 1;
+
+            case (size_t) -1:
+                // Illegal sequence. mbrtocwc has already set errno.
+                return (size_t) -1;
+
+            case (size_t) -3:
+                assert(!"Codec had buffered two characters");
+                _PDCLIB_UNREACHABLE;
+                return 0;
+
+            case (size_t) -2:
+                // Incomplete character, continue
+                break;
+        }
+    }
+
+    // _PendClear state
+    res = _PDCLIB_mbrtocwc_l(pwc, s, n, ps, l);
+    switch(res) {
+        case (size_t) -3:
+            // Converted entirely from internal state
+            ps->_PendChar  = *s;
+            ps->_PendState = _PendPrefix;
+            return 1;
+        default:
+            return res;
+    }
+}
+
+size_t mbrtowc(
+    wchar_t *restrict pwc, 
+    const char *restrict s, 
+    size_t n, 
+    mbstate_t *restrict ps
+)
+{
+    return mbrtowc_l(pwc, s, n, ps, _PDCLIB_threadlocale());
+}
+
+#endif
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+
+int main( void )
+{
+    TESTCASE( NO_TESTDRIVER );
+    return TEST_RESULTS;
+}
+#endif
-- 
2.40.0