add libc building to agbcc.

1 files changed, 77 insertions, 0 deletions

diff --git a/libc/stdlib/mbtowc.c b/libc/stdlib/mbtowc.c
new file mode 100644
index 0000000..01ec53e
--- /dev/null
+++ b/libc/stdlib/mbtowc.c
@@ -0,0 +1,77 @@
+/*
+FUNCTION
+<<mbtowc>>---minimal multibyte to wide char converter
+
+INDEX
+	mbtowc
+
+ANSI_SYNOPSIS
+	#include <stdlib.h>
+	int mbtowc(wchar_t *<[pwc]>, const char *<[s]>, size_t <[n]>);
+
+TRAD_SYNOPSIS
+	#include <stdlib.h>
+	int mbtowc(<[pwc]>, <[s]>, <[n]>)
+	wchar_t *<[pwc]>;
+	const char *<[s]>;
+	size_t <[n]>;
+
+DESCRIPTION
+When MB_CAPABLE is not defined, this is a minimal ANSI-conforming 
+implementation of <<mbtowc>>.  In this case,
+only ``multi-byte character sequences'' recognized are single bytes,
+and they are ``converted'' to themselves.
+Each call to <<mbtowc>> copies one character from <<*<[s]>>> to
+<<*<[pwc]>>>, unless <[s]> is a null pointer.  The argument n
+is ignored.
+
+When MB_CAPABLE is defined, this routine calls <<_mbtowc_r>> to perform
+the conversion, passing a state variable to allow state dependent
+decoding.  The result is based on the locale setting which may
+be restricted to a defined set of locales.
+
+RETURNS
+This implementation of <<mbtowc>> returns <<0>> if
+<[s]> is <<NULL>> or is the empty string; 
+it returns <<1>> if not MB_CAPABLE or
+the character is a single-byte character; it returns <<-1>>
+if n is <<0>> or the multi-byte character is invalid; 
+otherwise it returns the number of bytes in the multibyte character.
+If the return value is -1, no changes are made to the <<pwc>>
+output string.  If the input is the empty string, a wchar_t nul
+is placed in the output string and 0 is returned.  If the input
+has a length of 0, no changes are made to the <<pwc>> output string.
+
+PORTABILITY
+<<mbtowc>> is required in the ANSI C standard.  However, the precise
+effects vary with the locale.
+
+<<mbtowc>> requires no supporting OS subroutines.
+*/
+
+#include <stdlib.h>
+
+int
+_DEFUN (mbtowc, (pwc, s, n),
+        wchar_t *pwc _AND
+        const char *s _AND
+        size_t n)
+{
+#ifdef MB_CAPABLE
+        static int state;
+
+        return _mbtowc_r (_REENT, pwc, s, n, &state);
+#else /* not MB_CAPABLE */
+        if (s == NULL)
+                return 0;
+        if (n == 0)
+                return -1;
+        if (pwc)
+                *pwc = (wchar_t) *s;
+        return (*s != '\0');
+#endif /* not MB_CAPABLE */
+}
+
+
+
+