vi: add expandtab option

This implements the vim option expandtab in BusyBox vi.  From
vim help:

  In Insert mode: Use the appropriate number of spaces to insert a
  <Tab>.  Spaces are used in indents with the '>' and '<' commands and
  when 'autoindent' is on.  To insert a real tab when 'expandtab' is
  on, use CTRL-V<Tab>.

This implementation doesn't change how BusyBox vi handles autoindent:
it continues to copy the indentation from a neighbouring line.  If
that line has tabs in its indentation so too will the new line.

function                                             old     new   delta
char_insert                                          563     679    +116
next_column                                            -      48     +48
.rodata                                           105211  105236     +25
colon                                               3844    3855     +11
refresh                                             1000     982     -18
move_to_col                                           83      59     -24
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/2 up/down: 200/-42)           Total: 158 bytes

Signed-off-by: Peter D <urmum69@snopyta.org>
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Ron Yorston 2021-04-17 09:25:11 +01:00 committed by Denys Vlasenko
parent d9136efd7a
commit 310ef23280

View File

@ -289,11 +289,13 @@ struct globals {
#if ENABLE_FEATURE_VI_SETOPTS
smallint vi_setops; // set by setops()
#define VI_AUTOINDENT (1 << 0)
#define VI_ERR_METHOD (1 << 1)
#define VI_IGNORECASE (1 << 2)
#define VI_SHOWMATCH (1 << 3)
#define VI_TABSTOP (1 << 4)
#define VI_EXPANDTAB (1 << 1)
#define VI_ERR_METHOD (1 << 2)
#define VI_IGNORECASE (1 << 3)
#define VI_SHOWMATCH (1 << 4)
#define VI_TABSTOP (1 << 5)
#define autoindent (vi_setops & VI_AUTOINDENT)
#define expandtab (vi_setops & VI_EXPANDTAB )
#define err_method (vi_setops & VI_ERR_METHOD) // indicate error with beep or flash
#define ignorecase (vi_setops & VI_IGNORECASE)
#define showmatch (vi_setops & VI_SHOWMATCH )
@ -301,6 +303,7 @@ struct globals {
// order of constants and strings must match
#define OPTS_STR \
"ai\0""autoindent\0" \
"et\0""expandtab\0" \
"fl\0""flash\0" \
"ic\0""ignorecase\0" \
"sm\0""showmatch\0" \
@ -309,6 +312,7 @@ struct globals {
#define clear_openabove() (vi_setops &= ~VI_TABSTOP)
#else
#define autoindent (0)
#define expandtab (0)
#define err_method (0)
#define openabove (0)
#define set_openabove() ((void)0)
@ -759,6 +763,27 @@ static int next_tabstop(int col)
return col + ((tabstop - 1) - (col % tabstop));
}
static int next_column(char c, int co)
{
if (c == '\t')
co = next_tabstop(co);
else if ((unsigned char)c < ' ' || c == 0x7f)
co++; // display as ^X, use 2 columns
return co + 1;
}
#if ENABLE_FEATURE_VI_SETOPTS
static int get_column(char *p)
{
const char *r;
int co = 0;
for (r = begin_line(p); r < p; r++)
co = next_column(*r, co);
return co;
}
#endif
//----- Erase the Screen[] memory ------------------------------
static void screen_erase(void)
{
@ -838,11 +863,7 @@ static void sync_cursor(char *d, int *row, int *col)
do { // drive "co" to correct column
if (*tp == '\n') //vda || *tp == '\0')
break;
if (*tp == '\t') {
co = next_tabstop(co);
} else if ((unsigned char)*tp < ' ' || *tp == 0x7f) {
co++; // display as ^X, use 2 columns
}
co = next_column(*tp, co) - 1;
// inserting text before a tab, don't include its position
if (cmd_mode && tp == d - 1 && *d == '\t') {
co++;
@ -1807,12 +1828,8 @@ static char *move_to_col(char *p, int l)
do {
if (*p == '\n') //vda || *p == '\0')
break;
if (*p == '\t') {
co = next_tabstop(co);
} else if (*p < ' ' || *p == 127) {
co++; // display as ^X, use 2 columns
}
} while (++co <= l && p++ < end);
co = next_column(*p, co);
} while (co <= l && p++ < end);
return p;
}
@ -2104,6 +2121,17 @@ static char *char_insert(char *p, char c, int undo) // insert the char c at 'p'
p--;
p = text_hole_delete(p, p, ALLOW_UNDO_QUEUED);
}
} else if (c == '\t' && expandtab) { // expand tab
int col = get_column(p);
col = next_tabstop(col) - col + 1;
while (col--) {
# if ENABLE_FEATURE_VI_UNDO
undo_push_insert(p, 1, undo);
# else
modified_count++;
# endif
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) {
@ -2871,11 +2899,13 @@ static void colon(char *buf)
# if ENABLE_FEATURE_VI_SETOPTS
status_line_bold(
"%sautoindent "
"%sexpandtab "
"%sflash "
"%signorecase "
"%sshowmatch "
"tabstop=%u",
autoindent ? "" : "no",
expandtab ? "" : "no",
err_method ? "" : "no",
ignorecase ? "" : "no",
showmatch ? "" : "no",
@ -3753,7 +3783,7 @@ static void do_cmd(int c)
i = count_lines(p, q); // # of lines we are shifting
for ( ; i > 0; i--, p = next_line(p)) {
if (c == '<') {
// shift left- remove tab or 8 spaces
// shift left- remove tab or tabstop spaces
if (*p == '\t') {
// shrink buffer 1 char
text_hole_delete(p, p, allow_undo);
@ -3767,7 +3797,7 @@ static void do_cmd(int c)
}
}
} else /* if (c == '>') */ {
// shift right -- add tab or 8 spaces
// shift right -- add tab or tabstop spaces
char_insert(p, '\t', allow_undo);
}
#if ENABLE_FEATURE_VI_UNDO