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Diffstat (limited to 'src/multibyte/mbrtowc.c')
-rw-r--r--src/multibyte/mbrtowc.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/src/multibyte/mbrtowc.c b/src/multibyte/mbrtowc.c
new file mode 100644
index 00000000..09badebe
--- /dev/null
+++ b/src/multibyte/mbrtowc.c
@@ -0,0 +1,58 @@
+/*
+ * This code was written by Rich Felker in 2010; no copyright is claimed.
+ * This code is in the public domain. Attribution is appreciated but
+ * unnecessary.
+ */
+
+#include <stdlib.h>
+#include <inttypes.h>
+#include <wchar.h>
+#include <errno.h>
+
+#include "internal.h"
+
+size_t mbrtowc(wchar_t *wc, const char *src, size_t n, mbstate_t *st)
+{
+ static unsigned internal_state;
+ unsigned c;
+ const unsigned char *s = src;
+ const unsigned N = n;
+
+ if (!st) st = (void *)&internal_state;
+ c = *(unsigned *)st;
+
+ if (!s) {
+ s = "";
+ wc = (void *)&wc;
+ n = 1;
+ } else if (!wc) wc = (void *)&wc;
+
+ if (!n) return -2;
+ if (!c) {
+ if ((unsigned)*s < 0x80) return !!(*wc = *s);
+ if ((unsigned)*s-SA > SB-SA) goto ilseq;
+ c = bittab[*s++-SA]; n--;
+ }
+
+ if (n) {
+ if (OOB(c,*s)) goto ilseq;
+loop:
+ c = c<<6 | *s++-0x80; n--;
+ if (!(c&(1U<<31))) {
+ *(unsigned *)st = 0;
+ *wc = c;
+ return N-n;
+ }
+ if (n) {
+ if ((unsigned)*s-0x80 >= 0x40) goto ilseq;
+ goto loop;
+ }
+ }
+
+ *(unsigned *)st = c;
+ return -2;
+ilseq:
+ *(unsigned *)st = FAILSTATE;
+ errno = EILSEQ;
+ return -1;
+}