vi: fix faulty undo after autoinsert

Enable autoinsert and enter the following with an indent of three
spaces:

   line 1
   line 2

Using 'u' to undo the last insert results in:

   line1e 2

The insertion of the indent hasn't been properly recorded.

Since recording insertions is a common operation add a convenience
function, undo_push_insert(), to handle this and use it to record
the autoindent correctly.

function                                             old     new   delta
undo_push_insert                                       -      36     +36
string_insert                                        133     129      -4
char_insert                                          518     473     -45
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 36/-49)            Total: -13 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 22 insertions, 35 deletions

diff --git a/editors/vi.c b/editors/vi.c
index 32144abaa..c6adeb311 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -598,6 +598,7 @@ static void check_context(char);	// remember context for '' command
 #if ENABLE_FEATURE_VI_UNDO
 static void flush_undo_data(void);
 static void undo_push(char *, unsigned int, unsigned char);	// Push an operation on the undo stack
+static void undo_push_insert(char *, int, int); // convenience function
 static void undo_pop(void);	// Undo the last operation
 # if ENABLE_FEATURE_VI_UNDO_QUEUE
 static void undo_queue_commit(void);	// Flush any queued objects to the undo stack
@@ -2011,19 +2012,7 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
 		c = get_one_char();
 		*p = c;
 #if ENABLE_FEATURE_VI_UNDO
-		switch (undo) {
-			case ALLOW_UNDO:
-				undo_push(p, 1, UNDO_INS);
-				break;
-			case ALLOW_UNDO_CHAIN:
-				undo_push(p, 1, UNDO_INS_CHAIN);
-				break;
-# if ENABLE_FEATURE_VI_UNDO_QUEUE
-			case ALLOW_UNDO_QUEUED:
-				undo_push(p, 1, UNDO_INS_QUEUED);
-				break;
-# endif
-		}
+		undo_push_insert(p, 1, undo);
 #else
 		modified_count++;
 #endif /* ENABLE_FEATURE_VI_UNDO */
@@ -2051,19 +2040,7 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
 		if (c == '\n')
 			undo_queue_commit();
 # endif
-		switch (undo) {
-			case ALLOW_UNDO:
-				undo_push(p, 1, UNDO_INS);
-				break;
-			case ALLOW_UNDO_CHAIN:
-				undo_push(p, 1, UNDO_INS_CHAIN);
-				break;
-# if ENABLE_FEATURE_VI_UNDO_QUEUE
-			case ALLOW_UNDO_QUEUED:
-				undo_push(p, 1, UNDO_INS_QUEUED);
-				break;
-# endif
-		}
+		undo_push_insert(p, 1, undo);
 #else
 		modified_count++;
 #endif /* ENABLE_FEATURE_VI_UNDO */
@@ -2083,7 +2060,7 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
 				p += bias;
 				q += bias;
 #if ENABLE_FEATURE_VI_UNDO
-				undo_push(p, len, UNDO_INS);
+				undo_push_insert(p, len, undo);
 #endif
 				memcpy(p, q, len);
 				p += len;
@@ -2392,6 +2369,23 @@ static void undo_push(char *src, unsigned int length, uint8_t u_type)	// Add to
 	modified_count++;
 }
 
+static void undo_push_insert(char *p, int len, int undo)
+{
+	switch (undo) {
+		case ALLOW_UNDO:
+			undo_push(p, len, UNDO_INS);
+			break;
+		case ALLOW_UNDO_CHAIN:
+			undo_push(p, len, UNDO_INS_CHAIN);
+			break;
+# if ENABLE_FEATURE_VI_UNDO_QUEUE
+		case ALLOW_UNDO_QUEUED:
+			undo_push(p, len, UNDO_INS_QUEUED);
+			break;
+# endif
+	}
+}
+
 static void undo_pop(void)	// Undo the last operation
 {
 	int repeat;
@@ -2665,14 +2659,7 @@ static uintptr_t string_insert(char *p, const char *s, int undo) // insert the s
 
 	i = strlen(s);
 #if ENABLE_FEATURE_VI_UNDO
-	switch (undo) {
-		case ALLOW_UNDO:
-			undo_push(p, i, UNDO_INS);
-			break;
-		case ALLOW_UNDO_CHAIN:
-			undo_push(p, i, UNDO_INS_CHAIN);
-			break;
-	}
+	undo_push_insert(p, i, undo);
 #endif
 	bias = text_hole_make(p, i);
 	p += bias;