mds-kbdc: most of the built-in functions

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 84 insertions, 0 deletions

diff --git a/src/mds-kbdc/string.c b/src/mds-kbdc/string.c
new file mode 100644
index 0000000..ca33b83
--- /dev/null
+++ b/src/mds-kbdc/string.c
@@ -0,0 +1,84 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "string.h"
+
+#include <libmdsserver/macros.h>
+
+#include <stdlib.h>
+
+
+
+/**
+ * Get the length of a string.
+ * 
+ * @param   string  The string.
+ * @return          The length of the string.
+ */
+size_t string_length(const char32_t* restrict string)
+{
+  size_t i = 0;
+  while (string[i] >= 0)
+    i++;
+  return i;
+}
+
+
+/**
+ * Convert a NUL-terminated UTF-8 string to a -1-terminated UTF-32 string.
+ * 
+ * @param   string  The UTF-8 string.
+ * @return          The string in UTF-32, `NULL` on error.
+ */
+char32_t* string_decode(const char* restrict string)
+{
+  size_t i, j, n, length = 0;
+  char32_t* rc;
+  
+  /* Get the length of the UTF-32 string, excluding termination. */
+  for (i = 0; string[i]; i++)
+    if ((string[i] & 0xC0) != 0x80)
+      length++;
+  
+  /* Allocated UTF-32 string. */
+  if (xmalloc(rc, length + 1, char32_t))
+    return NULL;
+  
+  /* Convert to UTF-32. */
+  for (i = j = n = 0; string[i]; i++)
+    {
+      char c = string[i];
+      if (n)
+	{
+	  rc[j] <<= 6, rc[j] |= c & 0x3F;
+	  if (--n == 0)
+	    j++;
+	}
+      else if ((c & 0xC0) == 0xC0)
+	{
+	  while (c & 0x80)
+	    n++, c = (char)(c << 1);
+	  rc[j] = c >> n--;
+	}
+      else
+	rc[j++] = c & 255;
+    }
+  
+  /* -1-terminate and return. */
+  return rc[length] = -1, rc;
+}
+