1 files changed, 51 insertions, 0 deletions
diff --git a/stdio/fgetwc.c b/stdio/fgetwc.c
new file mode 100644
index 0000000..6411236
--- /dev/null
+++ b/stdio/fgetwc.c
@@ -0,0 +1,51 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/stdio/stdio.h"
+#include "libc/str/thompike.h"
+#include "libc/str/tpdecodecb.internal.h"
+
+/**
+ * Reads UTF-8 character from stream.
+ * @return wide character or -1 on EOF or error
+ */
+wint_t fgetwc(FILE *f) {
+  int c, n;
+  wint_t b, x, y;
+  if (f->beg < f->end) {
+    b = f->buf[f->beg++] & 0xff;
+  } else if ((c = fgetc(f)) != -1) {
+    b = c;
+  } else {
+    return -1;
+  }
+  if (b < 0300) return b;
+  n = ThomPikeLen(b);
+  x = ThomPikeByte(b);
+  while (--n) {
+    if ((c = fgetc(f)) == -1) return -1;
+    y = c;
+    if (ThomPikeCont(y)) {
+      x = ThomPikeMerge(x, y);
+    } else {
+      ungetc(y, f);
+      return b;
+    }
+  }
+  return x;
+}