From fc7868602ecf0d761a9a877141add4a9b6918d02 Mon Sep 17 00:00:00 2001 From: Ron Yorston Date: Thu, 3 Mar 2022 11:35:46 +0000 Subject: vi: improved handling of backspace in replace mode In replace mode ('R' command) the backspace character should get special treatment: - backspace only goes back to the start of the replacement; - backspacing over replaced characters restores the original text. Prior to this commit BusyBox vi deleted the characters both before and after the cursor in replace mode. function old new delta undo_pop - 235 +235 char_insert 858 884 +26 indicate_error 81 84 +3 find_range 654 657 +3 static.text_yank 77 79 +2 do_cmd 4486 4243 -243 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 4/1 up/down: 269/-243) Total: 26 bytes Signed-off-by: Ron Yorston Signed-off-by: Denys Vlasenko --- editors/vi.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'editors') diff --git a/editors/vi.c b/editors/vi.c index d37cd48a3..4257c0fdc 100644 --- a/editors/vi.c +++ b/editors/vi.c @@ -224,6 +224,7 @@ #endif +#define isbackspace(c) ((c) == term_orig.c_cc[VERASE] || (c) == 8 || (c) == 127) enum { MAX_TABSTOP = 32, // sanity limit @@ -342,6 +343,7 @@ struct globals { int last_modified_count; // = -1; int cmdline_filecnt; // how many file names on cmd line int cmdcnt; // repetition count + char *rstart; // start of text in Replace mode unsigned rows, columns; // the terminal screen is this size #if ENABLE_FEATURE_VI_ASK_TERMINAL int get_rowcol_error; @@ -474,6 +476,7 @@ struct globals { #define last_modified_count (G.last_modified_count) #define cmdline_filecnt (G.cmdline_filecnt ) #define cmdcnt (G.cmdcnt ) +#define rstart (G.rstart ) #define rows (G.rows ) #define columns (G.columns ) #define crow (G.crow ) @@ -1212,7 +1215,7 @@ static char *get_input_line(const char *prompt) c = get_one_char(); if (c == '\n' || c == '\r' || c == 27) break; // this is end of input - if (c == term_orig.c_cc[VERASE] || c == 8 || c == 127) { + if (isbackspace(c)) { // user wants to erase prev char write1("\b \b"); // erase char on screen buf[--i] = '\0'; @@ -2174,8 +2177,16 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p' p += 1 + stupid_insert(p, ' '); } #endif - } else if (c == term_orig.c_cc[VERASE] || c == 8 || c == 127) { // Is this a BS - if (p > text) { + } else if (isbackspace(c)) { + if (cmd_mode == 2) { + // special treatment for backspace in Replace mode + if (p > rstart) { + p--; +#if ENABLE_FEATURE_VI_UNDO + undo_pop(); +#endif + } + } else if (p > text) { p--; p = text_hole_delete(p, p, ALLOW_UNDO_QUEUED); // shrink buffer 1 char } @@ -3703,9 +3714,9 @@ static void do_cmd(int c) undo_queue_commit(); } else { if (1 <= c || Isprint(c)) { - if (c != 27) - dot = yank_delete(dot, dot, PARTIAL, YANKDEL, ALLOW_UNDO); // delete char - dot = char_insert(dot, c, ALLOW_UNDO_CHAIN); // insert new char + if (c != 27 && !isbackspace(c)) + dot = yank_delete(dot, dot, PARTIAL, YANKDEL, ALLOW_UNDO); + dot = char_insert(dot, c, ALLOW_UNDO_CHAIN); } goto dc1; } @@ -4264,6 +4275,7 @@ static void do_cmd(int c) dc5: cmd_mode = 2; undo_queue_commit(); + rstart = dot; break; case KEYCODE_DELETE: if (dot < end - 1) -- cgit v1.2.1