From ed8c80f48d3fe2d8772b566dca3d997ecb750147 Mon Sep 17 00:00:00 2001
From: Andrew Borodin <aborodin@vmail.ru>
Date: Mon, 18 Feb 2013 12:13:05 +0400
Subject: [PATCH] New editor buffer API to delete character at cursor position.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
---
 src/editor/edit.c       | 20 +++-------------
 src/editor/editbuffer.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/editor/editbuffer.h |  2 ++
 3 files changed, 69 insertions(+), 17 deletions(-)

diff --git a/src/editor/edit.c b/src/editor/edit.c
index a661e78d4..c4d231d33 100644
--- a/src/editor/edit.c
+++ b/src/editor/edit.c
@@ -2577,17 +2577,9 @@ edit_delete (WEdit * edit, gboolean byte_delete)
         if (edit->last_get_rule > edit->buffer.curs1)
             edit->last_get_rule--;
 
-        p = edit->buffer.buffers2[(edit->buffer.curs2 - 1) >> S_EDIT_BUF_SIZE][EDIT_BUF_SIZE -
-                                                                 ((edit->buffer.curs2 -
-                                                                   1) & M_EDIT_BUF_SIZE) - 1];
+        p = edit_buffer_delete (&edit->buffer);
 
-        if (!(edit->buffer.curs2 & M_EDIT_BUF_SIZE))
-        {
-            g_free (edit->buffer.buffers2[edit->buffer.curs2 >> S_EDIT_BUF_SIZE]);
-            edit->buffer.buffers2[edit->buffer.curs2 >> S_EDIT_BUF_SIZE] = NULL;
-        }
         edit->last_byte--;
-        edit->buffer.curs2--;
         edit_push_undo_action (edit, p + 256);
     }
 
@@ -2646,15 +2638,9 @@ edit_backspace (WEdit * edit, gboolean byte_delete)
         if (edit->last_get_rule >= edit->buffer.curs1)
             edit->last_get_rule--;
 
-        p = *(edit->buffer.buffers1[(edit->buffer.curs1 - 1) >> S_EDIT_BUF_SIZE] +
-              ((edit->buffer.curs1 - 1) & M_EDIT_BUF_SIZE));
-        if (((edit->buffer.curs1 - 1) & M_EDIT_BUF_SIZE) == 0)
-        {
-            g_free (edit->buffer.buffers1[edit->buffer.curs1 >> S_EDIT_BUF_SIZE]);
-            edit->buffer.buffers1[edit->buffer.curs1 >> S_EDIT_BUF_SIZE] = NULL;
-        }
+        p = edit_buffer_backspace (&edit->buffer);
+
         edit->last_byte--;
-        edit->buffer.curs1--;
         edit_push_undo_action (edit, p);
     }
     edit_modification (edit);
diff --git a/src/editor/editbuffer.c b/src/editor/editbuffer.c
index f061ebc3a..f76204ba2 100644
--- a/src/editor/editbuffer.c
+++ b/src/editor/editbuffer.c
@@ -355,6 +355,70 @@ edit_buffer_insert_ahead (edit_buffer_t * buf, int c)
 
 /* --------------------------------------------------------------------------------------------- */
 /**
+ * Basic low level single character buffer alterations and movements at the cursor: delete character
+ * at the cursor position.
+ *
+ * @param buf pointer to editor buffer
+ * @param c character to insert
+ */
+
+int
+edit_buffer_delete (edit_buffer_t * buf)
+{
+    unsigned char c;
+    off_t prev;
+    off_t i;
+
+    prev = buf->curs2 - 1;
+
+    i = prev & M_EDIT_BUF_SIZE;
+    c = buf->buffers2[prev >> S_EDIT_BUF_SIZE][EDIT_BUF_SIZE - 1 - i];
+
+    if ((buf->curs2 & M_EDIT_BUF_SIZE) == 0)
+    {
+        g_free (buf->buffers2[buf->curs2 >> S_EDIT_BUF_SIZE]);
+        buf->buffers2[buf->curs2 >> S_EDIT_BUF_SIZE] = NULL;
+    }
+
+    buf->curs2 = prev;
+
+    return c;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Basic low level single character buffer alterations and movements at the cursor: delete character
+ * before the cursor position and move left.
+ *
+ * @param buf pointer to editor buffer
+ * @param c character to insert
+ */
+
+int
+edit_buffer_backspace (edit_buffer_t * buf)
+{
+    unsigned char c;
+    off_t prev;
+    off_t i;
+
+    prev = buf->curs1 - 1;
+
+    i = prev & M_EDIT_BUF_SIZE;
+    c = buf->buffers1[prev >> S_EDIT_BUF_SIZE][i];
+
+    if (i == 0)
+    {
+        g_free (buf->buffers1[buf->curs1 >> S_EDIT_BUF_SIZE]);
+        buf->buffers1[buf->curs1 >> S_EDIT_BUF_SIZE] = NULL;
+    }
+
+    buf->curs1 = prev;
+
+    return c;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
  * Load file into editor buffer
  *
  * @param buf pointer to editor buffer
diff --git a/src/editor/editbuffer.h b/src/editor/editbuffer.h
index 4f83672c9..b62e9a380 100644
--- a/src/editor/editbuffer.h
+++ b/src/editor/editbuffer.h
@@ -60,6 +60,8 @@ int edit_buffer_get_prev_utf (const edit_buffer_t * buf, off_t byte_index, int *
 
 void edit_buffer_insert (edit_buffer_t * buf, int c);
 void edit_buffer_insert_ahead (edit_buffer_t * buf, int c);
+int edit_buffer_delete (edit_buffer_t * buf);
+int edit_buffer_backspace (edit_buffer_t * buf);
 
 off_t edit_buffer_read_file (edit_buffer_t * buf, int fd, off_t size);
 off_t edit_buffer_write_file (edit_buffer_t * buf, int fd);
-- 
2.11.4.GIT