summaryrefslogtreecommitdiff
path: root/newlib/libc/stdlib/mblen_r.c
diff options
context:
space:
mode:
Diffstat (limited to 'newlib/libc/stdlib/mblen_r.c')
-rw-r--r--newlib/libc/stdlib/mblen_r.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/newlib/libc/stdlib/mblen_r.c b/newlib/libc/stdlib/mblen_r.c
new file mode 100644
index 00000000000..22d1d40e65c
--- /dev/null
+++ b/newlib/libc/stdlib/mblen_r.c
@@ -0,0 +1,66 @@
+/*
+FUNCTION
+<<_mblen_r>>---reentrant minimal multibyte length function
+
+INDEX
+ _mblen_r
+
+ANSI_SYNOPSIS
+ #include <stdlib.h>
+ int _mblen_r(struct _reent *<[r]>, const char *<[s]>, size_t <[n]>, int *<[state]>);
+
+TRAD_SYNOPSIS
+ #include <stdlib.h>
+ int _mblen_r(<[r]>, <[s]>, <[n]>, <[state]>)
+ struct _reent *<[r]>;
+ const char *<[s]>;
+ size_t <[n]>;
+ int *<[state]>;
+
+DESCRIPTION
+When MB_CAPABLE is not defined, this is a minimal ANSI-conforming
+implementation of <<_mblen_r>>. In this case, the
+only ``multi-byte character sequences'' recognized are single bytes,
+and thus <<1>> is returned unless <[s]> is the null pointer or
+has a length of 0 or is the empty string.
+
+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 <<_mblen_r>> returns <<0>> if
+<[s]> is <<NULL>> or the empty string; it returns <<1>> if not MB_CAPABLE or
+the character is a single-byte character; it returns <<-1>>
+if the multi-byte character is invalid; otherwise it returns
+the number of bytes in the multibyte character.
+
+PORTABILITY
+<<_mblen>> is required in the ANSI C standard. However, the precise
+effects vary with the locale.
+
+<<_mblen_r>> requires no supporting OS subroutines.
+*/
+
+#include <stdlib.h>
+
+int
+_DEFUN (_mblen_r, (r, s, n, state),
+ struct _reent *r _AND
+ const char *s _AND
+ size_t n _AND
+ int *state)
+{
+#ifdef MB_CAPABLE
+
+ return _mbtowc_r (r, NULL, s, n, state);
+#else /* not MB_CAPABLE */
+ if (s == NULL || *s == '\0')
+ return 0;
+ if (n == 0)
+ return -1;
+ return 1;
+#endif /* not MB_CAPABLE */
+}
+