commit 976c8f455221eb599d1c446eafd88d51d7d2aa65
author Behdad Esfahbod <behdad@behdad.org> Wed Jul 16 15:34:20 2014 -0400
committer Behdad Esfahbod <behdad@behdad.org> Wed Jul 16 15:34:20 2014 -0400
tree d19f800fe6442515511bee1d15d6c257881dbc4d
parent bcba8b45024e1eca8be77ca2657de1dc44dbf8fb

New API: hb_buffer_[sg]et_replacement_codepoint()

With this change, we now by default replace broken UTF-8/16/32 bits
with U+FFFD.  This can be changed by calling new API on the buffer.
Previously the replacement value used to be (hb_codepoint_t)-1.

Note that hb_buffer_clear_contents() does NOT reset the replacement
character.

See discussion here:

https://github.com/behdad/harfbuzz/commit/6f13b6d62daae4989e3cc2fe4b168e5c59650964

New API:

  hb_buffer_set_replacement_codepoint()
  hb_buffer_get_replacement_codepoint()

src/hb-buffer.cc

diff --git a/src/hb-buffer.cc b/src/hb-buffer.cc
index 242cded..2377ba4 100644
--- a/src/hb-buffer.cc
+++ b/src/hb-buffer.cc
@@ -178,6 +178,7 @@
 
   hb_unicode_funcs_destroy (unicode);
   unicode = hb_unicode_funcs_get_default ();
+  replacement = HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT;
 
   clear ();
 }
@@ -703,6 +704,7 @@
     const_cast<hb_unicode_funcs_t *> (&_hb_unicode_funcs_nil),
     HB_SEGMENT_PROPERTIES_DEFAULT,
     HB_BUFFER_FLAG_DEFAULT,
+    HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT,
 
     HB_BUFFER_CONTENT_TYPE_INVALID,
     true, /* in_error */
@@ -1048,6 +1050,42 @@
 
 
 /**
+ * hb_buffer_set_replacement_codepoint:
+ * @buffer: a buffer.
+ * @replacement: 
+ *
+ * 
+ *
+ * Since: 1.0
+ **/
+void
+hb_buffer_set_replacement_codepoint (hb_buffer_t    *buffer,
+				     hb_codepoint_t  replacement)
+{
+  if (unlikely (hb_object_is_inert (buffer)))
+    return;
+
+  buffer->replacement = replacement;
+}
+
+/**
+ * hb_buffer_get_replacement_codepoint:
+ * @buffer: a buffer.
+ *
+ * 
+ *
+ * Return value: 
+ *
+ * Since: 1.0
+ **/
+hb_codepoint_t
+hb_buffer_get_replacement_codepoint (hb_buffer_t    *buffer)
+{
+  return buffer->replacement;
+}
+
+
+/**
  * hb_buffer_reset:
  * @buffer: a buffer.
  *
@@ -1299,6 +1337,7 @@
 		   int           item_length)
 {
   typedef hb_utf_t<T, true> utf_t;
+  const hb_codepoint_t replacement = buffer->replacement;
 
   assert (buffer->content_type == HB_BUFFER_CONTENT_TYPE_UNICODE ||
 	  (!buffer->len && buffer->content_type == HB_BUFFER_CONTENT_TYPE_INVALID));
@@ -1330,7 +1369,7 @@
     while (start < prev && buffer->context_len[0] < buffer->CONTEXT_LENGTH)
     {
       hb_codepoint_t u;
-      prev = utf_t::prev (prev, start, &u);
+      prev = utf_t::prev (prev, start, &u, replacement);
       buffer->context[0][buffer->context_len[0]++] = u;
     }
   }
@@ -1341,7 +1380,7 @@
   {
     hb_codepoint_t u;
     const T *old_next = next;
-    next = utf_t::next (next, end, &u);
+    next = utf_t::next (next, end, &u, replacement);
     buffer->add (u, old_next - (const T *) text);
   }
 
@@ -1351,7 +1390,7 @@
   while (next < end && buffer->context_len[1] < buffer->CONTEXT_LENGTH)
   {
     hb_codepoint_t u;
-    next = utf_t::next (next, end, &u);
+    next = utf_t::next (next, end, &u, replacement);
     buffer->context[1][buffer->context_len[1]++] = u;
   }