add utf8 validity checking API

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@861 fefdeb5f-60dc-0310-8127-8f9354f1896f

2 files changed, 142 insertions, 0 deletions

diff --git a/src/polypcore/utf8.c b/src/polypcore/utf8.c
new file mode 100644
index 00000000..b7758439
--- /dev/null
+++ b/src/polypcore/utf8.c
@@ -0,0 +1,115 @@
+/* $Id */
+
+/* This file is based on the GLIB utf8 validation functions. The
+ * original license text follows. */
+
+/* gutf8.c - Operations on UTF-8 strings.
+ *
+ * Copyright (C) 1999 Tom Tromey
+ * Copyright (C) 2000 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+
+#include "utf8.h"
+
+#define UNICODE_VALID(Char)                   \
+    ((Char) < 0x110000 &&                     \
+     (((Char) & 0xFFFFF800) != 0xD800) &&     \
+     ((Char) < 0xFDD0 || (Char) > 0xFDEF) &&  \
+     ((Char) & 0xFFFE) != 0xFFFE)
+   
+     
+#define CONTINUATION_CHAR                           \
+ do {                                     \
+  if ((*(const unsigned char *)p & 0xc0) != 0x80) /* 10xxxxxx */ \
+    goto error;                                     \
+  val <<= 6;                                        \
+  val |= (*(const unsigned char *)p) & 0x3f;                     \
+ } while(0)
+
+
+const char *
+pa_utf8_valid (const char *str)
+
+{
+  unsigned val = 0;
+  unsigned min = 0;
+  const char *p;
+
+  for (p = str; *p; p++)
+    {
+      if (*(const unsigned char *)p < 128)
+	/* done */;
+      else 
+	{
+	  const char *last;
+	  
+	  last = p;
+	  if ((*(const unsigned char *)p & 0xe0) == 0xc0) /* 110xxxxx */
+	    {
+	      if ( ((*(const unsigned char *)p & 0x1e) == 0))
+		goto error;
+	      p++;
+	      if ( ((*(const unsigned char *)p & 0xc0) != 0x80)) /* 10xxxxxx */
+		goto error;
+	    }
+	  else
+	    {
+	      if ((*(const unsigned char *)p & 0xf0) == 0xe0) /* 1110xxxx */
+		{
+		  min = (1 << 11);
+		  val = *(const unsigned char *)p & 0x0f;
+		  goto TWO_REMAINING;
+		}
+	      else if ((*(const unsigned char *)p & 0xf8) == 0xf0) /* 11110xxx */
+		{
+		  min = (1 << 16);
+		  val = *(const unsigned char *)p & 0x07;
+		}
+	      else
+		goto error;
+	      
+	      p++;
+	      CONTINUATION_CHAR;
+	    TWO_REMAINING:
+	      p++;
+	      CONTINUATION_CHAR;
+	      p++;
+	      CONTINUATION_CHAR;
+	      
+	      if ( (val < min))
+		goto error;
+
+	      if ( (!UNICODE_VALID(val)))
+		goto error;
+	    } 
+	  
+	  continue;
+	  
+	error:
+	  return NULL;
+	}
+    }
+
+  return str;
+}
diff --git a/src/polypcore/utf8.h b/src/polypcore/utf8.h
new file mode 100644
index 00000000..7f394978
--- /dev/null
+++ b/src/polypcore/utf8.h
@@ -0,0 +1,27 @@
+#ifndef fooutf8hfoo
+#define fooutf8hfoo
+
+/* $Id$ */
+
+/***
+  This file is part of polypaudio.
+ 
+  polypaudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+ 
+  polypaudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+ 
+  You should have received a copy of the GNU Lesser General Public
+  License along with polypaudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+const char *pa_utf8_valid(const char *str);
+
+#endif