100 Commits
Author SHA1 Message Date
Ron Yorston 64e967fabb lineedit: fix matching of directories when searching PATH
Commit 8baa643a3 (lineedit: match local directories when searching
PATH) included subdirectories of the current directory in the search
when tab-completing commands.

Unfortunately a short time later commit 1d180cd74 (lineedit: use
strncmp instead of is_prefixed_with (we know the length)) broke
this feature by returning an incorrect length for the array of paths.

Fix the length and reinstate matching of subdirectories.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2023-04-25 16:47:22 +02:00
Ron Yorston 5a9d2b6e02 libbb: make '--help' handling more consistent
Running an applet with '--help' as its only argument is treated
as a special case.  If additional arguments follow '--help' the
behaviour is inconsistent:

- applets which call single_argv() print help and do nothing else;

- applets which call getopt() report "unrecognized option '--help'"
  and print help anyway;

- expr says "expr: syntax error" and doesn't print help;

- printenv silently ignores '--help', prints any other variables
  and doesn't print help;

- realpath says "--help: No such file or directory", prints the path
  of any other files and doesn't print help.

If the first argument is '--help' ignore any other arguments and print
help.  This is more consistent and most likely what the user wanted.

See also commit 6bdfbc4cb (libbb: fix '--help' handling in
FEATURE_SH_NOFORK=y).

function                                             old     new   delta
show_usage_if_dash_dash_help                          75      69      -6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-6)               Total: -6 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-08-22 14:05:01 +02:00
Ron Yorston 298ac9507b lineedit: get PWD from ash
The line editing code and ash disagree when the current directory
is changed to a symbolic link:

   ~ $ mkdir real
   ~ $ ln -s real link
   ~ $ cd link
   ~/real $ pwd
   /home/rmyf36/link

Note the prompt says we're in ~/real.  Bash does:

   [rmy@random ~]$ cd link
   [rmy@random link]$ pwd
   /home/rmyf36/link

Ash uses the name supplied by the user while the line editing code
calls getcwd(3).  The discrepancy can be avoided by fetching the
value of PWD from ash.

Hush calls getcwd(3) when the directory is changed
so there's no disagreement with the line editing code.

There is no standard how shells should handle cd'ing into
symlinks.

function                                             old     new   delta
parse_and_put_prompt                                 838     869     +31

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-07-03 21:41:38 +02:00
Ron Yorston 2617a5e4c6 vi: handle autoindent in 'cc' command
When the 'cc' command is invoked with autoindent enabled it
should use the indent of the first line being changed.

The size of the indent has to be established before char_insert()
is called as the lines being changed are deleted.  Introduce a
new global variable, newindent, to handle this.  The indentcol
global is now effectively a static variable in char_insert().

function                                             old     new   delta
do_cmd                                              4247    4308     +61
vi_main                                              416     422      +6
char_insert                                          891     875     -16
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 67/-16)             Total: 51 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-06-26 19:38:31 +02:00
Ron Yorston af3b585815 vi: fix regression in autoindent handling
Suppose autoindent is enabled and we have a line with an initial
tab where we want to split the words onto separate lines:

	split the words

One way to do this is with the sequence 'f r<CR>;r<CR>', but in
BusyBox vi the result is:

	split

	he
words

This is a regression introduced by commit 9659a8db1 (vi: remove
autoindent from otherwise empty lines).  The amount of indentation
is being recorded when the 'r' command inserts a newline but
isn't subsequently reset.  A fix is to only record the indent
when in insert or replace mode.  Proper handling of the 'o' and
'O' commands then requires them to switch to insert mode before
calling char_insert() to insert a newline.

function                                             old     new   delta
char_insert                                          884     891      +7
do_cmd                                              4243    4247      +4
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 11/0)               Total: 11 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-06-26 19:38:28 +02:00
Ron Yorston 7d1c7d8337 ash,hush: use HOME for tab completion and prompts
ash and hush correctly use the value of HOME for tilde expansion.
However the line editing code in libbb obtains the user's home
directory by calling getpwuid().  Thus tildes in tab completion
and prompts may be interpreted differently than in tilde expansion.

When the line editing code is invoked from a shell make it use the
shell's interpretation of tilde.  This is similar to how GNU readline
and bash collaborate.

function                                             old     new   delta
get_homedir_or_NULL                                   29      72     +43
optschanged                                          119     126      +7
hush_main                                           1204    1211      +7
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/0 up/down: 57/0)               Total: 57 bytes

v2: Always check for HOME before trying the password database:  this
    is what GNU readline does.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-06-26 18:05:50 +02:00
Ron Yorston 95fec31be6 libbb: restore special handling of nomsg errors
The functions bb_perror_nomsg() and bb_perror_nomsg_and_die() are
used to print error messages where no specific information is
available.  For example:

   $ busybox mktemp -p /
   mktemp: (null): Permission denied

mktemp(3) doesn't tell us the name of the file it tried to create.

However, printing '(null)' is a regression introduced by commit
6937487be (libbb: reduce the overhead of single parameter bb_error_msg()
calls).  Restore the previous behaviour by reverting the changes to
the two functions mentioned:

   $ busybox mktemp -p /
   mktemp: Permission denied

function                                             old     new   delta
bb_perror_nomsg_and_die                                7      14      +7
bb_perror_nomsg                                        7      14      +7
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 14/0)               Total: 14 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-06-26 17:17:02 +02:00
Ron Yorston c93eb1a95b vi: fix backspace over tab in commands
Colon and search commands are entered on the status line.  Since
the cursor position wasn't being tracked backspacing over a tab
resulted in a mismatch between the actual and apparent content
of the command.

function                                             old     new   delta
get_input_line                                       178     180      +2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 2/0)                 Total: 2 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2022-04-20 16:06:04 +02:00
Ron Yorston fc7868602e 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 <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2022-03-04 22:57:05 +01:00
Ron Yorston 7105e4afdd printf: allow 0 as a flag and allow multiple flags
The '%' character in a format specification may be followed by
one or more flags from the list "+- #0".  BusyBox printf didn't
support the '0' flag or allow multiple flags to be provided.
As a result the formats '%0*d' and '%0 d' were considered to be
invalid.

The lack of support for '0' was pointed out by Andrew Snyder on the
musl mailing list:

   https://www.openwall.com/lists/musl/2021/12/14/2

function                                             old     new   delta
printf_main                                          860     891     +31
.rodata                                            99281   99282      +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 32/0)               Total: 32 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-12-17 21:13:26 +01:00
Ron Yorston 94eb1c4dc6 libbb: better coreutils compatibility for realpath
Add some tests which coreutils realpath pass but BusyBox realpath
fails (bar one).  Adjust xmalloc_realpath_coreutils() so the tests
pass:

- Expand symbolic links before testing whether the last path component
  exists.

- When the link target is a relative path canonicalize it by passing
  it through xmalloc_realpath_coreutils() as already happens for
  absolute paths.

- Ignore trailing slashes when finding the last path component and
  correctly handle the case where the only slash is at the start of
  the path.  This requires ignoring superfluous leading slashes.

- Undo all changes to the path so error messages from the caller show
  the original filename.

function                                             old     new   delta
xmalloc_realpath_coreutils                           214     313     +99

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-10-09 01:47:12 +02:00
Ron Yorston ed9aa89269 wget: implement --post-file
Add the --post-file option to send form data from a file.  As with
--post-data it's up to the user to ensure that the data is encoded
as appropriate:  all wget does is stuff the provided data into
the request.

The --post-data and --post-file options are mutually exclusive and
only one instance of either may be given.

Additionally:

- update the usage message to include missing details of the --post-data
  and --header options;

- free POST data if FEATURE_CLEAN_UP is enabled.

function                                             old     new   delta
packed_usage                                       34158   34214     +56
wget_main                                           2762    2805     +43
.rodata                                            99225   99240     +15
static.wget_longopts                                 266     278     +12
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/0 up/down: 126/0)             Total: 126 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-10-01 14:55:18 +02:00
Ron Yorston 56f0e886db cal: implement -m
Some people prefer the week to start on Monday.  Add the '-m'
option to support this.

function                                             old     new   delta
cal_main                                             926     966     +40
day_array                                            316     337     +21
packed_usage                                       34151   34158      +7
.rodata                                            99224   99225      +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/0 up/down: 69/0)               Total: 69 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-21 15:25:37 +02:00
Ron Yorston f27a6a94a7 libbb: code shrink parse_datestr (again)
Commit 9fe1548bb (date,touch: allow timezone offsets in dates)
mentioned the similarity between '@' format dates and those with
timezone offsets.  It didn't notice that as a result there's
common code which can be shared.

function                                             old     new   delta
parse_datestr                                        730     687     -43
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-43)             Total: -43 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-18 22:55:46 +02:00
Ron Yorston 3a65435eaa libbb: ensure mode_string is NUL terminated
If the mode_string array is no longer static we can't rely on
it being NUL terminated.

function                                             old     new   delta
bb_mode_string                                       115     118      +3

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-17 16:51:01 +02:00
Ron Yorston 9fe1548bbf date,touch: allow timezone offsets in dates
Allow ISO 8601 style dates to include a timezone offset.  Like
the '@' format these dates aren't relative to the user's current
timezone and shouldn't be subject to DST adjustment.

- The implementation uses the strptime() '%z' format specifier.
  This an extension which may not be available so the use of
  timezones is a configuration option.

- The 'touch' applet has been updated to respect whether DST
  adjustment is required, matching 'date'.

function                                             old     new   delta
parse_datestr                                        624     730    +106
static.fmt_str                                       106     136     +30
touch_main                                           388     392      +4
date_main                                            818     819      +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/0 up/down: 141/0)             Total: 141 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-17 00:11:30 +02:00
Ron Yorston 83e20cb81c getopt: code shrink
function                                             old     new   delta
.rodata                                            99277   99290     +13
normalize                                            177     142     -35
getopt_main                                          675     622     -53
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/2 up/down: 13/-88)            Total: -75 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-16 01:09:32 +02:00
Ron Yorston 3512ef8018 libbb: code shrink parse_datestr
The default build uses strptime() in parse_datestr() to support the
'month_name d HH:MM:SS YYYY' format of GNU date.  If we've linked
with strptime() there's an advantage is using it for other formats
too.

There's no change to the non-default, non-DESKTOP build.

function                                             old     new   delta
fmt_str                                                -     106    +106
.rodata                                            99216   99145     -71
parse_datestr                                        948     624    -324
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 106/-395)         Total: -289 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-15 08:09:45 +02:00
Ron Yorston 5726df5f94 ash: let ignoreeof only affect interactive shells
Commit fb7d6c89 from Harald van Dijk's gwsh variant of ash
(https://github.com/hvdijk/gwsh):

    ignoreeof is documented as only having an effect for interactive shells,
    but is implemented as having mostly the same effect for interactive
    shells as for non-interactive shells. Change the implementation to match
    the documentation.

    Test case:

      $SHELL -o ignoreeof /dev/null

function                                             old     new   delta
cmdloop                                              359     361      +2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 2/0)                 Total: 2 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-14 08:25:58 +02:00
Ron Yorston 50239a665c ash: stopped jobs should only prevent exit from interactive shell
When the user tries to exit an interactive shell with stopped jobs
present the shell issues a warning and only exits if the user
insists by trying to exit again.

This shouldn't apply to non-interactive shells.

Reported-by: Roberto A. Foglietta <roberto.foglietta@gmail.com>
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-14 08:16:15 +02:00
Ron Yorston 0beee20977 ash: fix ignoreeof option
The ignoreeof option should prevent an interactive shell from
exiting on EOF.  This hasn't worked in BusyBox ash since commit
727752d2d (ash: better fix for ash -c 'echo 5&' and ash -c 'sleep 5&'
with testcase).

Commit 3b4d04b77e (ash: input: Allow two consecutive calls to pungetc)
pulled in improved support for multiple calls to pungetc from dash,
thus rendering much of commit 727752d2d obsolete.  Removing this old
code fixes the problem with ignoreeof.

function                                             old     new   delta
__pgetc                                              605     587     -18
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-18)             Total: -18 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-14 08:16:15 +02:00
Ron Yorston 305a30d80b awk: fix read beyond end of buffer
Commit 7d06d6e18 (awk: fix printf %%) can cause awk printf to read
beyond the end of a strduped buffer:

  2349      while (*f && *f != '%')
  2350          f++;
  2351      c = *++f;

If the loop terminates because a NUL character is detected the
character after the NUL is read.  This can result in failures
depending on the value of that character.

function                                             old     new   delta
awk_printf                                           672     665      -7

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-09 18:12:21 +02:00
Ron Yorston 4a36ef11ac ash: regressions in process substitution
Stacy Harper reports that this script:

   test() { . /tmp/bb_test; }
   echo "export TEST=foo" >/tmp/bb_test
   test 2>/dev/null
   echo "$TEST"

correctly prints 'foo' in BusyBox 1.33 but hangs in 1.34.

Bisection suggested the problem was caused by commit a1b0d3856 (ash: add
process substitution in bash-compatibility mode).  Removing the call to
unwindredir() in cmdloop() introduced in that commit makes the script
work again.

Additionally, these examples of process substitution:

   while true; do cat <(echo hi); done
   f() { while true; do cat <(echo hi); done }
   f

result in running out of file descriptors.  This is a regression from
v5 of the process substitution patch caused by changes to evalcommand()
not being transferred to v6.

function                                             old     new   delta
static.pushredir                                       -      99     +99
evalcommand                                         1729    1750     +21
exitreset                                             69      86     +17
cmdloop                                              372     365      -7
unwindredir                                           28       -     -28
pushredir                                            112       -    -112
------------------------------------------------------------------------------
(add/remove: 1/2 grow/shrink: 2/1 up/down: 137/-147)          Total: -10 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-09-02 17:49:00 +02:00
Ron Yorston a51d953b95 vi: further changes to colon addresses
Improved error messages:

- specify when a search fails or a mark isn't set;
- warn when line addresses are out of range or when a range of
  lines is reversed.

Addresses are limited to the number of lines in the file so a
command like ':2000000000' (go to the two billionth line) no
longer causes a long pause.

Improved vi compatibility of '+' and '-' operators that aren't
followed immediately by a number:

   :4+++=       7
   :3-2=        1
   :3 - 2=      4 (yes, really!)

In a command like ':,$' the empty address before the separator now
correctly refers to the current line.  (The similar case ':1,' was
already being handled.)

And all with a tidy reduction in bloat (32-bit build):

function                                             old     new   delta
colon                                               4029    4069     +40
.rodata                                            99348   99253     -95
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 40/-95)            Total: -55 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-29 20:07:20 +02:00
Ron Yorston 922b58b3e4 tar,smemcap: silence compiler warning
gcc 11.2.1 complains that the tar header checksum might overflow
the checksum field.  It won't and using an unsigned int for the
calculation seems to convince the compiler too.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-22 15:44:57 +02:00
Ron Yorston 8817e285b7 shuf: speed-up when limited output is requested
A user noted that the following command was slower than they
expected:

   busybox shuf -i "1500000000-$(date +%s)" -n 5

At time of writing the range contains 128 million values.  On my
system this takes 7.7s whereas 'shuf' from coreutils takes a
handful of milliseconds.

Optimise BusyBox 'shuf' for cases where -n is specified by stopping
shuffling once the required number of lines have been processed.
On my system the time for the example is reduced to 0.4s.

function                                             old     new   delta
shuf_main                                            520     540     +20
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 20/0)               Total: 20 bytes

v2: Code shrink.  Since outlines <= numlines:
    - the loop in shuffle_lines() only needs to test the value of
      outlines;
    - shuffle_lines() can be called unconditionally.
    Update timing to allow for the 13 million seconds elapsed since v1.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-22 15:40:21 +02:00
Ron Yorston 74c4f356ae vi: code shrink print_literal()
Simplify the function print_literal() which is used to format a
string that may contain unprintable characters or control
characters.

- Unprintable characters were being displayed in normal text rather
  than the bold used for the rest of the message.  This doesn't seem
  particularly helpful and it upsets the calculation of the width
  of the message in show_status_line().  Use '?' rather than '.' for
  unprintable characters.

- Newlines in the string were displayed as both '^J' and '$', which
  is somewhat redundant.

function                                             old     new   delta
not_implemented                                      199     108     -91
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-91)             Total: -91 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-22 00:09:57 +02:00
Ron Yorston 08ad934ac4 vi: searches in colon commands should wrap
The '/' and '?' search commands wrap to the other end of the buffer
if the search target isn't found.  When searches are used to specify
addresses in colon commands they should do the same.

(In traditional vi and vim this behaviour is controlled by the
'wrapscan' option.  BusyBox vi doesn't have this option and always
uses the default behaviour.)

function                                             old     new   delta
colon                                               4033    4077     +44
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 44/0)               Total: 44 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-22 00:09:57 +02:00
Ron Yorston 4357569fdc rev: correct output for long input lines
The input buffer is initialised to a reasonable size and extended
if necessary.  When this happened the offset into the buffer wasn't
reset to zero so subsequent lines were appended to the long line.

Fix this and add some tests.

function                                             old     new   delta
rev_main                                             377     368      -9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-9)               Total: -9 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-22 00:08:18 +02:00
Ron Yorston 38e9c8c95b vi: don't right shift empty lines
The right shift command ('>') shouldn't affect empty lines.

function                                             old     new   delta
do_cmd                                              4860    4894     +34
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 34/0)               Total: 34 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-20 15:26:09 +02:00
Ron Yorston f9217cd235 vi: support ~/.exrc
Run initialisation commands from ~/.exrc.  As with EXINIT these
commands are processed before the first file is loaded.

Commands starting with double quotes are ignored.  This is how
comments are often included in .exrc.

function                                             old     new   delta
vi_main                                              268     406    +138
colon                                               4033    4071     +38
.rodata                                           108411  108442     +31
packed_usage                                       34128   34118     -10
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/1 up/down: 207/-10)           Total: 197 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-20 15:26:09 +02:00
Ron Yorston f07772f19e vi: changes to handling of -c and EXINIT
Rewrite handling of command line arguments so any number of -c
commands will be processed.  Previously only two -c commands
were allowed (or one if EXINIT was set).

Process commands from EXINIT before the first file is read into
memory, as specified by POSIX.

function                                             old     new   delta
run_cmds                                               -      77     +77
.rodata                                           108410  108411      +1
vi_main                                              305     268     -37
edit_file                                            816     764     -52
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/2 up/down: 78/-89)            Total: -11 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-20 15:26:09 +02:00
Ron Yorston 98cb561b5f cp: fix build failure with long options disabled
When long options were disabled cp failed to compile with:

coreutils/cp.c:130:9: error: empty enum is invalid
  130 |         };
      |         ^

Rearrange the conditional compilation to suit.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-08-15 18:26:56 +02:00
Ron Yorston e6f4145f29 vi: fix regex search compilation error
Building with FEATURE_VI_REGEX_SEARCH enabled fails.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
2021-07-13 18:23:43 +02:00
Ron Yorston 2759201401 vi: allow delimiter in ':s' to be escaped
When regular expressions are allowed in search commands it becomes
possible to escape the delimiter in search/replace commands.  For
example, this command will replace '/abc' with '/abc/':

   :s/\/abc/\/abc\//g

The code to split the command into 'find' and 'replace' strings
should allow for this possibility.

VI_REGEX_SEARCH isn't enabled by default.  When it is:

function                                             old     new   delta
strchr_backslash                                       -      38     +38
colon                                               4378    4373      -5
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/1 up/down: 38/-5)              Total: 33 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-07-13 14:42:20 +02:00
Ron Yorston c76c78740a vi: improve handling of anchored searches
Suppose we search for a git conflict marker '<<<<<<< HEAD' using
the command '/^<<<'.  Using 'n' to go to the next match finds
'<<<' on the current line, apparently ignoring the '^' anchor.

Set a flag in the compiled regular expression to indicate that the
start of the string should not be considered a beginning-of-line
anchor.  An exception has to be made when the search starts from
the beginning of the file.  Make a similar change for end-of-line
anchors.

This doesn't affect a default build with VI_REGEX_SEARCH disabled.
When it's enabled:

function                                             old     new   delta
char_search                                          247     285     +38

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-07-13 13:50:59 +02:00
Ron Yorston 2916443ab6 vi: use basic regular expressions for search
Both traditional vi and vim use basic regular expressions for
search.  Also, they don't allow matches to extend across line
endings.  Thus with the file:

   123
   234

the search '/2.*4$' should find the second '2', not the first.

Make BusyBox vi do the same.

Whether or not VI_REGEX_SEARCH is enabled:

function                                             old     new   delta
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0)                 Total: 0 bytes

Signed-off-by: Andrey Dobrovolsky <andrey.dobrovolsky.odessa@gmail.com>
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-07-13 13:36:29 +02:00
Ron Yorston b50ac07cba vi: allow 'gg' to specify a range
Commit 7b93e317c (vi: enable 'dG' command. Closes 11801) allowed
'G' to be used as a range specifier for change/yank/delete
operations.

Add similar support for 'gg'.  This requires setting the 'cmd_error'
flag if 'g' is followed by any character other than another 'g'.

function                                             old     new   delta
do_cmd                                              4852    4860      +8
.rodata                                           108179  108180      +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 9/0)                 Total: 9 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-07-13 13:32:13 +02:00
Ron Yorston 5dbbd0a6f5 vi: stored search pattern applies to ':s'
The same stored search pattern applies to both search ('/') and
search/replace (':s') operations.

A search/replace operation with an empty "find" string (':s//abc/')
should use the last stored search pattern, if available, and issue an
error message if there is none.

If the "find" string is not empty it should replace the stored search
pattern.

function                                             old     new   delta
colon                                               3952    4024     +72
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 72/0)               Total: 72 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-27 13:36:49 +02:00
Ron Yorston a84bbc5425 cp,mv: fix -t DIR option
When the '-t DIR' option is used the loop over the remaining
arguments should terminate when a NULL pointer is reached.

function                                             old     new   delta
mv_main                                              585     590      +5
cp_main                                              492     496      +4
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 9/0)                 Total: 9 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-25 00:23:29 +02:00
Ron Yorston 2dade4f18a uniq: really support -z
Commit 894466cc5 (uniq: support -z) added support for NUL delimited
output.  Unfortunately nobody told getopt32().

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-24 23:37:06 +02:00
Ron Yorston 51358757c7 vi: fix backward search with GNU regex
With FEATURE_VI_REGEX_SEARCH enabled backward searches don't work.
This is problematic on distros that enable regexes, such as Tiny
Core Linux and Fedora.

When calling GNU re_search() with a negative range parameter
(indicating a backward search) the start offset must be set to
the end of the area being searched.

The return value of re_search() is the offset of the matched pattern
from the start of the area being searched.  For a successful search
(positive return value) char_search() can return the pointer to
the start of the area plus the offset.

FEATURE_VI_REGEX_SEARCH isn't enabled by default but when it is:

function                                             old     new   delta
char_search                                          256     247      -9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-9)               Total: -9 bytes

Signed-off-by: Andrey Dobrovolsky <andrey.dobrovolsky.odessa@gmail.com>
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-21 15:37:28 +02:00
Ron Yorston 038d400709 vi: reject change command when motion fails
If the motion command used to define the range of a change, yank or
delete fails the whole command should be rejected.  BusyBox vi already
handled failed searches in these circumstances.  Add some more cases:

- non-existent mark: d'x

- movement beyond end of file: c99999+ or 99999<<

This is implemented using a global variable which is set when a command
error is detected.  Unlike the case of motion within a line it's
insufficient to check that the motion command doesn't move the cursor:
this fails to process 'LyL' correctly, for example, as the second 'L'
doesn't move the cursor.

function                                             old     new   delta
indicate_error                                        75      82      +7
find_range                                           686     692      +6
do_cmd                                              4851    4852      +1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/0 up/down: 14/0)               Total: 14 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-16 23:53:03 +02:00
Ron Yorston ac04eb3657 vi: up/down motion beyond end of file should fail
In traditional vi and vim line motion commands ('+'/'-'/'j'/'k')
fail if the movement would exceed the bounds of the file.  BusyBox vi
allowed such commands to succeed, leaving the cursor on the first or
last character of the file.

Make BusyBox vi work like vi/vim.

For the 'G'/'H'/'L' commands traditional vi treats an out of bounds
result as an error, vim doesn't.  BusyBox vi behaves like vim, both
before and after this patch.

function                                             old     new   delta
do_cmd                                              4785    4851     +66
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 66/0)               Total: 66 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-16 23:53:03 +02:00
Ron Yorston f1d21b7434 vi: keep autoindent if line isn't empty
When ESC is entered to leave insert mode any autoindent should only
be removed if there's no content beyond the indent.  This may be the
case if a line has been split by entering insert mode and then
entering a CR.

Add a check to ensure there's only a newline after the indent.

function                                             old     new   delta
char_insert                                          912     929     +17
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 17/0)               Total: 17 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-16 23:53:03 +02:00
Ron Yorston 52c4b7ac3b vi: initialise tabstop once not for each file
The default tabstop value should be set during early start up,
not reset for each new file.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-14 20:58:17 +02:00
Ron Yorston f7ed0e8ae0 vi: ':r' should insert text after current line
When no line number is specified ':read' should place the inserted
text after the current line, not before.

This used to be correct but was broken when commit 0c42a6b07
(vi: fix empty line range regression) revealed a bug in commit
7a8ceb4eb (vi: changes to line addresses for colon commands).

function                                             old     new   delta
colon                                               3960    3952      -8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8)               Total: -8 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-14 20:58:17 +02:00
Ron Yorston a1b0d3856d ash: add process substitution in bash-compatibility mode
Process substitution is a Korn shell feature that's also available
in bash and some other shells.  This patch implements process
substitution in ash when ASH_BASH_COMPAT is enabled.

function                                             old     new   delta
argstr                                              1386    1522    +136
strtodest                                              -      52     +52
readtoken1                                          3346    3392     +46
.rodata                                           183206  183250     +44
unwindredir                                            -      28     +28
cmdloop                                              365     372      +7
static.spclchars                                      10      12      +2
cmdputs                                              380     367     -13
exitreset                                             86      69     -17
evalcommand                                         1754    1737     -17
varvalue                                             675     634     -41
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 5/4 up/down: 315/-88)           Total: 227 bytes
   text	   data	    bss	    dec	    hex	filename
 953967	   4219	   1904	 960090	  ea65a	busybox_old
 954192	   4219	   1904	 960315	  ea73b	busybox_unstripped

v2: Replace array of file descriptors with a linked list.
    Include tests that were unaccountably omitted from v1.
v3: Update linked list code to the intended version.
v4: Change order of conditional code in cmdputs().
v5: Use existing popredir() mechanism to manage file descriptors.
v6: Rebase to latest version of BusyBox ash.  Reduce code churn.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-05 23:37:19 +02:00
Ron Yorston 9659a8db1d vi: remove autoindent from otherwise empty lines
Lines that have no content apart from automatic indentation should
be treated as empty when the user hits return or ESC.

The implementation uses the global variable 'indentcol'.  Usually
this is zero.  It can also be -1 to indicate an 'O' (open above)
command, replacing the overloading of the tabstop option bit.

A value greater than zero indicates that the current line has
been autoindented to the given column (or that the autoindent has
been adjusted with ctrl-D).  Any other change to the line resets
'indentcol' to zero.

Replace strspn() with ident_len().  The latter handles the unlikely
case that it's called on the last line of a file which doesn't have
a terminating newline.

function                                             old     new   delta
char_insert                                          741     912    +171
indent_len                                             -      42     +42
do_cmd                                              4781    4785      +4
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/0 up/down: 217/0)             Total: 217 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-02 06:29:34 +02:00
Ron Yorston 16e2fa9049 vi: make autoindent respect expandtab setting
Autoindent took a copy of the indent from a neighbouring line, which
may not have respected the expandtab setting.

Determine the target column and construct a suitable indent.  This
will consist entirely of spaces if expandtab is enabled or an
efficient combination of tabs and spaces otherwise.

function                                             old     new   delta
char_insert                                          719     741     +22
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 22/0)               Total: 22 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-02 06:16:36 +02:00
Ron Yorston d95f89ec57 vi: make cursor positioning more vi compatible
Commit 24effc7a3 (vi: cursor positioning after whole-line 'y')
tried to save a few bytes by treating whole-line deletion the
same as whole-line yank.  If the deletion removed the last lines
of the file the cursor was left beyond the end of the file.
Revert the part of the commit related to whole-line deletion.

Position the cursor on the first non-whitespace character of the
line when whole lines are 'put'.

function                                             old     new   delta
do_cmd                                              4759    4781     +22
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 22/0)               Total: 22 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-06-02 06:16:36 +02:00
Ron Yorston 8e71f2aab8 vi: :wq/:x should warn if there are more files to edit
':wq' or ':x' should issue a warning if there are more files to edit,
unless they're followed by '!'.

function                                             old     new   delta
colon                                               3911    3960     +49
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 49/0)               Total: 49 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-05-04 14:51:48 +02:00
Ron Yorston 24effc7a3f vi: cursor positioning after whole-line 'y'
The 'y' command to yank text should leave the cursor at the start
of the range.  This mostly works correctly in BusyBox vi but not
for whole-line yanks with backward motion, e.g. '2yk' to yank two
lines backwards.  In this case the cursor is left at the end of the
range.

Fix this by returning the actual range from find_range().  Cursor
positioning following whole-line deletion is inconsistent between
vim and traditional vi.  For BusyBox vi chose the option that uses
least code without being exactly compatible with either.

Also, find_range() preserved the value of 'dot', the current cursor
position.  Since this isn't used by either caller of find_range()
we can save a few bytes by not bothering.

function                                             old     new   delta
do_cmd                                              4730    4759     +29
find_range                                           749     686     -63
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 29/-63)            Total: -34 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-05-04 14:51:48 +02:00
Ron Yorston 0c42a6b072 vi: fix empty line range regression
Commit 7a8ceb4eb (vi: changes to line addresses for colon commands)
was supposed to address the issue:

  When the last address is empty it should refer to the current line.

This was intended to allow ranges of the form '1,' with an empty
last address.  It should have been expressed as:

  When the last address is empty *and the second last isn't* it
  should refer to the current line.

Otherwise a command like ':w' only writes the current line resulting
in serious loss of data.

function                                             old     new   delta
colon                                               3906    3911      +5
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 5/0)                 Total: 5 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-30 01:40:27 +02:00
Ron Yorston acd3079fd1 vi: expand '%' and '#' in colon commands
Track the current and alternate filenames.  The placeholders '%'
and '#' can be used in arguments to colon commands to represent
the current and alternate filenames respectively.  Backslash can
be used to allow literal '%' and '#' characters to be entered.

This feature is controlled by the configuration option
FEATURE_VI_COLON_EXPAND.

function                                             old     new   delta
expand_args                                            -     198    +198
colon                                               3751    3927    +176
update_filename                                        -      70     +70
init_filename                                          -      48     +48
.rodata                                           105218  105239     +21
get_one_char                                         115     124      +9
edit_file                                            835     838      +3
do_cmd                                              4724    4727      +3
init_text_buffer                                     190     172     -18
------------------------------------------------------------------------------
(add/remove: 3/0 grow/shrink: 5/1 up/down: 528/-18)           Total: 510 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston 852ffbee34 vi: fix buffer overrun; code shrink
It was possible for get_input_line() to store its NUL terminator
one character beyond the end of its buffer.

Code shrink in colon():

- Certain colon commands can be matched exactly, as any shorter
  string would be matched earlier, e.g. ':wq' versus ':write'.

- Command matching is now case sensitive so there's no need to
  check for 'N' or 'Q' suffixes.

- Rewrite how commands and arguments are split.

function                                             old     new   delta
colon                                               3848    3751     -97
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-97)             Total: -97 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston dadd909746 vi: improvements to ':read' command
Improvements to ':read':

- When a file is read into the current buffer the cursor should be
  placed on the first line read.

- If invoked without supplying a filename the current filename should
  be used.  This is similar to how ':edit' works.

- The code for ':edit' included an explicit check that the current
  filename was non-empty.  Both vim and traditional vi accept non-empty
  filenames, only issuing an error message when an attempt to use such
  a name fails.

- Allow undo of a file read.

function                                             old     new   delta
file_insert                                          367     382     +15
colon                                               3841    3848      +7
.rodata                                           105236  105218     -18
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 22/-18)              Total: 4 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston e6bc8a29a9 vi: preserve state when switching file
When a new file is opened from an existing editing session the
following details should be preserved:

- the last command used;
- the last character searched for on a line.

function                                             old     new   delta
edit_file                                            849     835     -14
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-14)             Total: -14 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston b9aaa375a3 vi: 'ZZ' should warn if there are more files to edit
When 'ZZ' was used to save the current file and more files were
available to edit BusyBox vi immediately moved on to the next file.
The correct behaviour is to issue a warning.

function                                             old     new   delta
do_cmd                                              4673    4724     +51
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 51/0)               Total: 51 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston 09172582da vi: saving unnamed file in readonly mode
Suppose vi is started with the command 'vi -R', that is, in readonly
mode with no filename.  Attempting to save the file with 'ZZ' or ':w'
results in the message:

   '(null)' is read only

Skip the code which prints this if no filename was provided, thus
falling through to file_write() which gives the more helpful message
'No current filename'.

function                                             old     new   delta
colon                                               3867    3874      +7
do_cmd                                              4668    4673      +5
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 12/0)               Total: 12 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston 3b9233f05f vi: adjust conditional compilation of modifying_cmds
Since commit 74d565ff1 (vi: make context marks more like vi) the
list of commands that modify the text is no longer required when
FEATURE_VI_YANKMARK is enabled, only FEATURE_VI_DOT_CMD.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston 7a8ceb4eb2 vi: changes to line addresses for colon commands
Make line addresses behave more like vi:

- Vi allows the user to enter an arbitrary number of addresses,
  though only the last two are used.  This simplifies get_address()
  by reducing the amount of state that needs to be carried.

- When a command requires a single address the last one entered is
  used.

- If addresses are separated by a ';' instead of a ',' the current
  line is updated to the left address.  This may be useful when a
  search is used to specify a range, e.g. ':/first/;/last/d'.

- When the last address is empty it should refer to the current line.

function                                             old     new   delta
colon                                               3855    3834     -21
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-21)             Total: -21 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-28 11:29:33 +02:00
Ron Yorston f277c9eebb vi: make de-indentation with ctrl-D more like vim
Commit ac6495f6f (vi: allow ctrl-D to reduce indentation) treated
ctrl-D during autoindent as a backspace.  This was adequate for
indentation using tabs but doesn't work well with the expandtab
option.  In the latter case it's necessary to backspace over all
the spaces.

Make ctrl-D work correctly when spaces are present in the indent.

Also, make it behave more like vim:

- ctrl-D is independent of autoindent;
- indentation is reduced even when the cursor isn't positioned at
  the end of the indent.

function                                             old     new   delta
char_insert                                          679     717     +38
get_column                                             -      37     +37
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/0 up/down: 75/0)               Total: 75 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-20 11:21:43 +02:00
Ron Yorston 310ef23280 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>
2021-04-20 11:21:43 +02:00
Ron Yorston f227726838 vi: allow line addresses to have an offset
Line addresses in colon commands can be defined using an expression
that includes '+' or '-' operators.  The implementation follows
traditional vi:

- The first term in the expression defines an address.  It can be
  an absolute line number, '.', '$', a search or a marker.

- The second and subsequent terms must be non-negative integers.

- If the first term is missing '.' is assumed.  If the operator is
  missing addition is assumed.  If the final term in missing an
  offset of 1 is assumed.

Thus the following are valid addresses:

  .+1   .+   +   .1
  .-1   .-   -

The following are not valid (though they are in vim):

  .+$   .$   2+.

function                                             old     new   delta
colon                                               3701    3844    +143
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 143/0)             Total: 143 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 47f78913f7 vi: allow backward search to specify line address
It should be possible to use a backward search as a line address
in colon commands.

function                                             old     new   delta
colon                                               3661    3701     +40
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 40/0)               Total: 40 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston d488def0e4 vi: detect and warn about invalid line addresses
BusyBox vi didn't have proper handling for invalid markers or
unsuccessful searches in colon line addresses.  This could result
in the wrong lines being affected by a change.

Detect when an invalid address is specified, propagate an error
indicator up the call chain and issue a warning.

function                                             old     new   delta
colon                                               3604    3661     +57
.rodata                                           105195  105211     +16
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 73/0)               Total: 73 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 5d1bb58b13 vi: code shrink colon line addresses
Remove some unnecessary code in get_one_address() and rewrite
get_address().

function                                             old     new   delta
colon                                               3325    3604    +279
get_one_address                                      342       -    -342
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/0 up/down: 279/-342)          Total: -63 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 74d565ff1f vi: make context marks more like vi
The context marks that are automatically updated and can be used
with the "''" command didn't behave the same as in vi.  Marks
were only being set for certain editing commands when they should
have been set on successful movement commands.

Make BusyBox vi behave more like vi.

function                                             old     new   delta
.rodata                                           105179  105194     +15
do_cmd                                              4723    4668     -55
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 15/-55)            Total: -40 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 47c3eaa22f vi: correct autoindent for 'O' command
Opening a line above the current line with the 'O' command should
use the current, not previous, line to determine how much to
autoindent.

function                                             old     new   delta
char_insert                                          531     563     +32
do_cmd                                              4746    4723     -23
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 32/-23)              Total: 9 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston ac6495f6fb vi: allow ctrl-D to reduce indentation
When whitespace has been automatically added to a new line due to
autoindent entering ctrl-D should reduce the level of indentation.

Implement an approximation of this by treating ctrl-D as backspace.
For the common case of indentation using tabs this is good enough.
My attempt at a full implementation was three times bigger.

function                                             old     new   delta
char_insert                                          476     531     +55
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 55/0)               Total: 55 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston d6e653d667 vi: don't move cursor when yanking whole lines
When whole lines are yanked using 'yy' or 'Y' vi doesn't change the
cursor position.  Make BusyBox vi do the same.

function                                             old     new   delta
do_cmd                                              4776    4786     +10
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 10/0)               Total: 10 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 38ae0f3e3e vi: reset command count when specifying '0' range
Since commit a54450248 (vi: allow the '.' command to have a
repetition count) using '0' to specify a range doesn't work with
a non-zero repeat count, e.g. '1d0'.  Users wouldn't normally try
to do that but the '.' command does.

Add a special case in get_motion_char() to handle this.

function                                             old     new   delta
find_range                                           737     746      +9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 9/0)                 Total: 9 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 033fa3d5c6 vi: code shrink motion by paragraph
Use a hand-coded loop to search for paragraph boundaries instead
of calling char_search().  We were using a loop anyway to skip
consecutive newlines.

function                                             old     new   delta
do_cmd                                              4792    4752     -40
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-40)             Total: -40 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston d9d19896a9 vi: position cursor on last column of tab
Vi places the cursor on the last column of a tab character whereas
BusyBox vi puts it on the first.  This is disconcerting for
experienced vi users and makes it impossible to distinguish
visually between an empty line and one containing just a tab.

It wasn't always this way.  Prior to commit e3cbfb91d (vi: introduce
FEATURE_VI_8BIT) BusyBox vi also put the cursor on the last column.
However there were problems with cursor positioning when text was
inserted before a tab.  Commit eaabf0675 (vi: multiple fixes by
Natanael Copa) includes a partial attempt to fix this.  (The code is
still present but it's never executed.  Clever compilers optimise it
away.)

Revert the changes of commit e3cbfb91d and fix the insert problem
for all tabs, not just the first.

To quote Natanael:  "Costs a few bytes but its worth it imho".

function                                             old     new   delta
refresh                                              974    1000     +26
move_to_col                                           81      83      +2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 28/0)               Total: 28 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 9b2a3895ee vi: correctly record deleted characters
The undo queue didn't record deleted characters properly.  For
example, insert some text, backspace over a couple of characters
then exit insert mode.  At this point undo will restore two nulls
instead of the deleted characters.

The fix is in undo_push():  record the state of the UNDO_USE_SPOS
flag and clear it before using 'u_type'.

Also, update the comments to reflect the fact that UNDO_QUEUED_FLAG
isn't actually used.

function                                             old     new   delta
undo_push                                            443     435      -8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8)               Total: -8 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-15 13:09:12 +02:00
Ron Yorston 27c1bc8dfb build system: avoid build failure during bisection
Commit 4bdc914ff (build system: fix compiler warnings) added a
test on the return value of fgets() in split-include.c.

During bisection it's possible to go back to a state where a
configuration value didn't exist.  This results in an empty
include file corresponding to the missing feature.  If a
subsequent bisection returns to a state where the feature exists
split-include treats the empty file as an error and the build
fails.

Add a call to ferror() to distinguish between fgets() failing
due to an error and due to there being no data to read.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-13 18:26:46 +02:00
Ron Yorston f4a9908b4c vi: improvements to reporting of changes
Traditional vi is mostly silent about the results of yank, delete,
change, undo or substitution commands.  Vim reports some details
about undo and substitution.  BusyBox vi is positively verbose in
comparison.

Make some improvements to BusyBox vi:

- Add vim-like reporting of changes caused by substitutions, of
  the form '64 substitutions on 53 lines'.  This replaces a fairly
  useless report of the result of the last change made.

- Ensure that the report about put operations correctly reflects the
  newly introduced repetition count.

- Commit 25d2592640 tried to limit status updates for delete and
  yank operations by detecting whether the register had changed.
  This didn't always work because the previously allocated memory
  could be reused for the new register contents.  Fix this by
  delaying freeing the old register until after the new one has
  been allocated.

- Add a configuration option to control verbose status reporting.
  This is on by default.  Turning it off make BusyBox vi as taciturn
  as traditional vi and saves 435 bytes.

function                                             old     new   delta
colon                                               3212    3292     +80
yank_status                                            -      74     +74
static.text_yank                                      99      86     -13
string_insert                                        130      76     -54
do_cmd                                              4842    4776     -66
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/3 up/down: 154/-133)           Total: 21 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:56 +02:00
Ron Yorston 99fb5f2144 vi: issue a warning on failure to find a character
When a search for a character within a line fails issue a warning.

function                                             old     new   delta
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0)                 Total: 0 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:56 +02:00
Ron Yorston 6220b4d531 vi: make the substitute command more like vi
Make the ':s/find/replace/g' command behave more like vi:

- the final delimiter is optional if no flag is specified;

- the cursor is moved to the first visible character of the last
  line where a substitution was made;

- a warning is displayed if no substitution was made.

function                                             old     new   delta
colon                                               3156    3212     +56
.rodata                                           105133  105142      +9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 65/0)               Total: 65 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston 951c6ded3a vi: make put commands more like vi
Make the put commands 'p' and 'P' behave more like vi:

- allow a repetition count to be specified;

- when the text being inserted doesn't include a newline the cursor
  should be positioned at the end of the inserted text.

function                                             old     new   delta
do_cmd                                              4765    4842     +77
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 77/0)               Total: 77 bytes

v2: Don't break build when FEATURE_VI_UNDO is disabled.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston a54450248b vi: allow the '.' command to have a repetition count
The '.' command repeats the last text change.  When it has a
repetition count replay the change the number of times requested.
Update the stored count if it changes.  For example,

   3dw     deletes 3 words
   .       deletes another 3 words
   2.      deletes 2 words and changes the stored count
   .       deletes 2 words

function                                             old     new   delta
do_cmd                                              4746    4781     +35
.rodata                                           105133  105138      +5
edit_file                                            887     849     -38
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 40/-38)              Total: 2 bytes

v2: Change implementation to include repetition count in string.
    Otherwise repeating 'r' doesn't work properly.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston fe76569daa vi: allow 'r' command to be aborted, repeated
Make the 'r' command behave more like vi:

- abort the command if ESC is entered after the 'r';

- allow a repeat count to be entered before the 'r';

- if the repeat count exceeds the space available on the line don't
  change any characters and issue an alert.

function                                             old     new   delta
do_cmd                                              4679    4746     +67
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 67/0)               Total: 67 bytes

v2: Don't break build when FEATURE_VI_UNDO is disabled.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston b18c7bf702 vi: improvements to undo
The left shift operator ('<') didn't support undo at all; right
shift ('>') required changes to be undone separately for each line.
Allow both types of shift to be undone as a single operation.

Also, neither traditional vi nor vim yank the lines being shifted by
the '<' and '>' commands, so remove that call to yank_delete();

When a repetition count was specified for the '~', 'x', 'X' or 's'
commands the changes had to be undone one character at a time.
Allow undo as a single operation (though the delete and change
parts of the 's' command still have to be undone separately).

function                                             old     new   delta
undo_push_insert                                      37      40      +3
do_cmd                                              4695    4663     -32
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 3/-32)             Total: -29 bytes

v2: Don't break build when FEATURE_VI_UNDO is  disabled.  Don't reset
    'undo_del' too early in '~' handling code.  Code shrink '~'.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston e577afca7c vi: more fixes to range selection by word
An example in my vi book presents different ways to fix the spelling
of the last word in a line:

   ... anyweigh.

With the cursor on the 'e' the command 'cway' should do the job.
Since commit 776b56d77, though, 'cw' incorrectly includes the full
stop in the range if we're on the last line of the file.

(Prior to commit 776b56d77 BusyBox vi got 'cw' right in this case but
'cW' wrong:  it *didn't* delete the full stop.)

Reinstate some of the bloat removed by the earlier commit to fix this.

Also, commit 7b4c2276a (vi: fix word operations across line boundaries)
incorrectly ignores whitespace after a single character word.  Adjust
the condition to avoid this.

function                                             old     new   delta
find_range                                           707     737     +30
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 30/0)               Total: 30 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston b7b1119d9f vi: improvements to range selection
Rewrite find_range(), pushing quite a bit of code from do_cmd()
down into it.

- The commands 'y', 'd', 'c', '<' and '>' can be given twice to
  specify a whole-line range.  BusyBox vi actually accepted any
  second character from that group, e.g. 'dc' or '<y', with the
  latter being accepted even if yank was disabled.  Require the
  two characters to match.

- '<' and '>' commands followed by ESC incorrectly issued an alert.

- Allow search commands and a marker (specified as "y'a", for example)
  to define a range for those operators that support it.

function                                             old     new   delta
find_range                                           518     707    +189
.rodata                                           105119  105133     +14
get_motion_char                                       68       -     -68
do_cmd                                              4860    4695    -165
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/1 up/down: 203/-233)          Total: -30 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston 7ce0e75c1f vi: code shrink search commands
Changes to search commands ('/', '?', 'n' and 'N'):

- Rewrite to be smaller and (possibly) clearer.

- Issue a warning when a repeat search is requested without a
  previous search having been made.

Vim and BusyBox vi support a repetition count for searches though
the original vi doesn't.  If the count exceeds the number of
occurrences of the search string the search may loop through the
file multiple times.

function                                             old     new   delta
.rodata                                           105135  105119     -16
do_cmd                                              4898    4860     -38
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-54)             Total: -54 bytes

Signed-off-by; Ron Yorston <rmy@pobox.com>

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-11 00:18:55 +02:00
Ron Yorston 9f017d9db0 vi: changes to option handling
Since commit 70ee23399 (vi: code shrink) the ':set' command is
unable to process multiple options on a line.  Fix this by
temporarily null-terminating each option.

Change the default setting for all options to off to match vim.
Actually, 'flash' isn't an option in vim, only traditional vi,
where it's on by default.  In vim the corresponding option is
'visualbell' which defaults to off.  POSIX doesn't have either
of these.

Allow the abbreviation 'ts' for the 'tabstop' option.

Issue an error message if:

- an option is not implemented
- an option that takes a value has no '=' or has a 'no' prefix
- a boolean option has a '='

function                                             old     new   delta
colon                                               2944    3003     +59
.rodata                                           103171  103189     +18
vi_main                                              274     270      -4
setops                                                73       -     -73
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 2/1 up/down: 77/-77)              Total: 0 bytes

v2: Try harder to detect invalid options.  Thanks to Peter D for pointing
    this out.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-04-08 12:50:01 +02:00
Ron Yorston 24198f652f vi: deal with invalid movements in shift commands
Since commit 25d259264 (vi: make buffer handling more vi-like)
find_range() can return early when an invalid movement is
specified.

The call to find_range() in the code that handles shift commands
('<' and '>') doesn't check for this condition.  Previously this
only resulted in the current line being shifted but it can now
result in a segfault.

Check for an invalid movement and notify the user without taking
any further action.

function                                             old     new   delta
do_cmd                                              4890    4898      +8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 8/0)                 Total: 8 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-30 14:51:27 +02:00
Ron Yorston a25b4c2c42 vi: code shrink
- In the '+' and '-' commands the call to dot_skip_over_ws() is
  only needed for the final line processed so it can be moved out
  of the while loop.

- Marking sync_cursor() NOINLINE doesn't seem to offer the same
  advantages it did in 2009 (commit adf922ec2).

function                                             old     new   delta
refresh                                              694     974    +280
do_cmd                                              4900    4887     -13
sync_cursor                                          336       -    -336
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/1 up/down: 280/-349)          Total: -69 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston d56da68057 vi: improve operations involving paragraph movement
Movement by paragraph doesn't always involve whole lines.  If the
cursor is positioned in the middle of a line deleting to either end
of the paragraph will result in one partial line and zero or more
full lines.

Adjust the end of ranges delimited by paragraph movement to more
closely match what vi does.

function                                             old     new   delta
find_range                                           467     518     +51
at_eof                                                 -      49     +49
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/0 up/down: 100/0)             Total: 100 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 8b571bd7b5 vi: improve motion by paragraph
When moving by paragraph ('{' and '}'):

- Treat multiple empty lines as a single paragraph separator.

- When no paragraph separator is found move to the start or end of
  the file depending on the direction of motion.

function                                             old     new   delta
do_cmd                                              4821    4900     +79
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 79/0)               Total: 79 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston d3b74826c5 vi: allow repetition count for paragraph motion
The paragraph motion commands '{' and '}' should accept a count.

function                                             old     new   delta
do_cmd                                              5054    5071     +17
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 17/0)               Total: 17 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 1e84daf054 vi: allow motion count for change/delete/yank/shift
The motion that determines the range of a change, delete, yank
or shift operation can have its own count.  Thus the commands
'5dd' and 'd5d' are equivalent:  both delete 5 lines.

When the command itself also has a count the two values are
multiplied.  Thus the command '2d3w' deletes 6 words and '2D3G'
deletes from the current line to line 6.

(When dealing with structured data it might make sense to think in
units of 3 words so '2d3w' is deleting 2 such units.  It doesn't
seem quite as sensible to express 'delete from current line to line 6'
as '2D3G' but vi permits it.)

function                                             old     new   delta
get_motion_char                                        -      68     +68
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/0 up/down: 68/0)               Total: 68 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston d4c46037a6 vi: support more commands for range selection
Add 'F', 'T' and '|' as commands that can be used to specify a
range for change/delete/yank operations.

function                                             old     new   delta
.rodata                                           105129  105135      +6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 6/0)                 Total: 6 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 15f4ac3ca9 vi: improvements to character search within line
- Use a common routine to handle all commands to search for a
  character in a line.

- When searching for the nth occurrence of a character don't move
  the cursor if fewer than n occurrences are present.

- Add support for the 'T' command, search backwards for character
  after next occurrence of given character.

function                                             old     new   delta
do_cmd                                              4861    4805     -56
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-56)             Total: -56 bytes

v2: Add parentheses to avoid searches continuing past end of line.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 50a2db7dff vi: remember cursor column during vertical motion
When the 'j'/'k' commands or up/down arrow keys are used to move
the cursor vertically 'vi' remembers the original cursor column
and positions the cursor there if possible.  Also, if the '$'
command has been used to position the cursor at the end of a line
vertical movements keep the cursor at the end of the line.

Make BusyBox 'vi' do the same.

function                                             old     new   delta
refresh                                              674     694     +20
do_cmd                                              4853    4861      +8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 28/0)               Total: 28 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 18871c3f2b vi: 'G'/'M' commands move to first visible character
The 'G' command with no target (meaning 'go to last line') should
position the cursor on the first visible character of the line, as
it already does in other cases.

The 'M' command  should position the cursor on the first visible
character (as 'H' and 'L' already do).

function                                             old     new   delta
do_cmd                                              4842    4853     +11
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 11/0)               Total: 11 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 5ae25f40bd vi: don't overwrite existing file
If the name of the file being written doesn't match the current
filename and the output file already exists vi should issue a
warning and not overwrite the file.

Because the test only compares the file names it's somewhat over-
protective.  If the current file name is 'my_text' and the user tries
to save to './my_text' they'll be prevented from doing so.

function                                             old     new   delta
colon                                               3092    3151     +59
.rodata                                           105118  105146     +28
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 87/0)               Total: 87 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:16:21 +02:00
Ron Yorston 25d2592640 vi: make buffer handling more vi-like
Vi places text affected by change/delete/yank operations into a
buffer.  The contents of such buffers can be restored with the put
commands, 'p' or 'P'.  These behave differently depending on whether
the buffer contains whole lines or partial lines.  For whole lines
the text is copied into the file on the line before (P) or after
(p) the current line.  For partial lines the text is copied before
or after the current cursor position.

Whether an operation results in whole or partial lines depends on
the command used.

BusyBox vi treats any buffer with a newline as though it contained
whole lines.  This is incorrect.  Deleting multiple words across
a line boundary results in a buffer with a newline but not having
whole lines.

Rework how buffers are handled to behave more like vi.

function                                             old     new   delta
static.text_yank                                      79      99     +20
colon                                               3092    3097      +5
edit_file                                            885     887      +2
yank_delete                                          127     112     -15
.rodata                                           105139  105101     -38
find_range                                           514     467     -47
do_cmd                                              5088    4842    -246
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/4 up/down: 27/-346)          Total: -319 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2021-03-29 12:05:53 +02:00