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command.c
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command.c
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/*
* Copyright (C) 1984-2000 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information about less, or for information on how to
* contact the author, see the README file.
*/
/*
* User-level command processor.
*/
#include "less.h"
#include "position.h"
#include "option.h"
#include "cmd.h"
extern int erase_char, kill_char;
extern int sigs;
extern int quit_at_eof;
extern int quit_if_one_screen;
extern int squished;
extern int hit_eof;
extern int sc_width;
extern int sc_height;
extern int swindow;
extern int jump_sline;
extern int quitting;
extern int wscroll;
extern int top_scroll;
extern int ignore_eoi;
extern int secure;
extern int hshift;
extern int show_attn;
extern char *every_first_cmd;
extern char *curr_altfilename;
extern char version[];
extern struct scrpos initial_scrpos;
extern IFILE curr_ifile;
extern void constant *ml_search;
extern void constant *ml_examine;
#if SHELL_ESCAPE || PIPEC
extern void constant *ml_shell;
#endif
#if EDITOR
extern char *editor;
extern char *editproto;
#endif
extern int screen_trashed; /* The screen has been overwritten */
static char ungot[UNGOT_SIZE];
static char *ungotp = NULL;
#if SHELL_ESCAPE
static char *shellcmd = NULL; /* For holding last shell command for "!!" */
#endif
static int mca; /* The multicharacter command (action) */
static int search_type; /* The previous type of search */
static int number; /* The number typed by the user */
static char optchar;
static int optflag;
static int optgetname;
static POSITION bottompos;
#if PIPEC
static char pipec;
#endif
static void multi_search();
/*
* Move the cursor to lower left before executing a command.
* This looks nicer if the command takes a long time before
* updating the screen.
*/
static void
cmd_exec()
{
clear_attn();
lower_left();
flush();
}
/*
* Set up the display to start a new multi-character command.
*/
static void
start_mca(action, prompt, mlist, cmdflags)
int action;
char *prompt;
void *mlist;
int cmdflags;
{
mca = action;
clear_cmd();
cmd_putstr(prompt);
set_mlist(mlist, cmdflags);
}
public int
in_mca()
{
return (mca != 0 && mca != A_PREFIX);
}
/*
* Set up the display to start a new search command.
*/
static void
mca_search()
{
if (search_type & SRCH_FORW)
mca = A_F_SEARCH;
else
mca = A_B_SEARCH;
clear_cmd();
if (search_type & SRCH_NO_MATCH)
cmd_putstr("Non-match ");
if (search_type & SRCH_FIRST_FILE)
cmd_putstr("First-file ");
if (search_type & SRCH_PAST_EOF)
cmd_putstr("EOF-ignore ");
if (search_type & SRCH_NO_MOVE)
cmd_putstr("Keep-pos ");
if (search_type & SRCH_NO_REGEX)
cmd_putstr("Regex-off ");
if (search_type & SRCH_FORW)
cmd_putstr("/");
else
cmd_putstr("?");
set_mlist(ml_search, 0);
}
/*
* Set up the display to start a new toggle-option command.
*/
static void
mca_opt_toggle()
{
int no_prompt;
int flag;
char *dash;
no_prompt = (optflag & OPT_NO_PROMPT);
flag = (optflag & ~OPT_NO_PROMPT);
dash = (flag == OPT_NO_TOGGLE) ? "_" : "-";
mca = A_OPT_TOGGLE;
clear_cmd();
cmd_putstr(dash);
if (optgetname)
cmd_putstr(dash);
if (no_prompt)
cmd_putstr("(P)");
switch (flag)
{
case OPT_UNSET:
cmd_putstr("+");
break;
case OPT_SET:
cmd_putstr("!");
break;
}
set_mlist(NULL, 0);
}
/*
* Execute a multicharacter command.
*/
static void
exec_mca()
{
register char *cbuf;
cmd_exec();
cbuf = get_cmdbuf();
switch (mca)
{
case A_F_SEARCH:
case A_B_SEARCH:
multi_search(cbuf, number);
break;
case A_FIRSTCMD:
/*
* Skip leading spaces or + signs in the string.
*/
while (*cbuf == '+' || *cbuf == ' ')
cbuf++;
if (every_first_cmd != NULL)
free(every_first_cmd);
if (*cbuf == '\0')
every_first_cmd = NULL;
else
every_first_cmd = save(cbuf);
break;
case A_OPT_TOGGLE:
toggle_option(optchar, cbuf, optflag);
optchar = '\0';
break;
case A_F_BRACKET:
match_brac(cbuf[0], cbuf[1], 1, number);
break;
case A_B_BRACKET:
match_brac(cbuf[1], cbuf[0], 0, number);
break;
#if EXAMINE
case A_EXAMINE:
if (secure)
break;
edit_list(cbuf);
break;
#endif
#if SHELL_ESCAPE
case A_SHELL:
/*
* !! just uses whatever is in shellcmd.
* Otherwise, copy cmdbuf to shellcmd,
* expanding any special characters ("%" or "#").
*/
if (*cbuf != '!')
{
if (shellcmd != NULL)
free(shellcmd);
shellcmd = fexpand(cbuf);
}
if (secure)
break;
if (shellcmd == NULL)
lsystem("", "!done");
else
lsystem(shellcmd, "!done");
break;
#endif
#if PIPEC
case A_PIPE:
if (secure)
break;
(void) pipe_mark(pipec, cbuf);
error("|done", NULL_PARG);
break;
#endif
}
}
/*
* Add a character to a multi-character command.
*/
static int
mca_char(c)
int c;
{
char *p;
int flag;
char buf[3];
PARG parg;
switch (mca)
{
case 0:
/*
* Not in a multicharacter command.
*/
return (NO_MCA);
case A_PREFIX:
/*
* In the prefix of a command.
* This not considered a multichar command
* (even tho it uses cmdbuf, etc.).
* It is handled in the commands() switch.
*/
return (NO_MCA);
case A_DIGIT:
/*
* Entering digits of a number.
* Terminated by a non-digit.
*/
if ((c < '0' || c > '9') &&
editchar(c, EC_PEEK|EC_NOHISTORY|EC_NOCOMPLETE) == A_INVALID)
{
/*
* Not part of the number.
* Treat as a normal command character.
*/
number = cmd_int();
mca = 0;
cmd_accept();
return (NO_MCA);
}
break;
case A_OPT_TOGGLE:
/*
* Special case for the TOGGLE_OPTION command.
* If the option letter which was entered is a
* single-char option, execute the command immediately,
* so user doesn't have to hit RETURN.
* If the first char is + or -, this indicates
* OPT_UNSET or OPT_SET respectively, instead of OPT_TOGGLE.
* "--" begins inputting a long option name.
*/
if (optchar == '\0' && len_cmdbuf() == 0)
{
flag = (optflag & ~OPT_NO_PROMPT);
if (flag == OPT_NO_TOGGLE)
{
switch (c)
{
case '_':
/* "__" = long option name. */
optgetname = TRUE;
mca_opt_toggle();
return (MCA_MORE);
}
} else
{
switch (c)
{
case '+':
/* "-+" = UNSET. */
optflag = (flag == OPT_UNSET) ?
OPT_TOGGLE : OPT_UNSET;
mca_opt_toggle();
return (MCA_MORE);
case '!':
/* "-!" = SET */
optflag = (flag == OPT_SET) ?
OPT_TOGGLE : OPT_SET;
mca_opt_toggle();
return (MCA_MORE);
case CONTROL('P'):
optflag ^= OPT_NO_PROMPT;
mca_opt_toggle();
return (MCA_MORE);
case '-':
/* "--" = long option name. */
optgetname = TRUE;
mca_opt_toggle();
return (MCA_MORE);
}
}
}
if (optgetname)
{
/*
* We're getting a long option name.
* See if we've matched an option name yet.
* If so, display the complete name and stop
* accepting chars until user hits RETURN.
*/
struct option *o;
char *oname;
int lc;
if (c == '\n' || c == '\r')
{
/*
* When the user hits RETURN, make sure
* we've matched an option name, then
* pretend he just entered the equivalent
* option letter.
*/
if (optchar == '\0')
{
parg.p_string = get_cmdbuf();
error("There is no --%s option", &parg);
return (MCA_DONE);
}
optgetname = FALSE;
cmd_reset();
c = optchar;
} else
{
if (optchar != '\0')
{
/*
* Already have a match for the name.
* Don't accept anything but erase/kill.
*/
if (c == erase_char || c == kill_char)
return (MCA_DONE);
return (MCA_MORE);
}
/*
* Add char to cmd buffer and try to match
* the option name.
*/
if (cmd_char(c) == CC_QUIT)
return (MCA_DONE);
p = get_cmdbuf();
lc = islower(p[0]);
o = findopt_name(&p, &oname, NULL);
if (o != NULL)
{
/*
* Got a match.
* Remember the option letter and
* display the full option name.
*/
optchar = o->oletter;
if (!lc && islower(optchar))
optchar = toupper(optchar);
cmd_reset();
mca_opt_toggle();
for (p = oname; *p != '\0'; p++)
{
c = *p;
if (!lc && islower(c))
c = toupper(c);
if (cmd_char(c) != CC_OK)
return (MCA_DONE);
}
}
return (MCA_MORE);
}
} else
{
if (c == erase_char || c == kill_char)
break;
if (optchar != '\0')
/* We already have the option letter. */
break;
}
optchar = c;
if ((optflag & ~OPT_NO_PROMPT) != OPT_TOGGLE ||
single_char_option(c))
{
toggle_option(c, "", optflag);
return (MCA_DONE);
}
/*
* Display a prompt appropriate for the option letter.
*/
if ((p = opt_prompt(c)) == NULL)
{
buf[0] = '-';
buf[1] = c;
buf[2] = '\0';
p = buf;
}
start_mca(A_OPT_TOGGLE, p, (void*)NULL, 0);
return (MCA_MORE);
case A_F_SEARCH:
case A_B_SEARCH:
/*
* Special case for search commands.
* Certain characters as the first char of
* the pattern have special meaning:
* ! Toggle the NO_MATCH flag
* * Toggle the PAST_EOF flag
* @ Toggle the FIRST_FILE flag
*/
if (len_cmdbuf() > 0)
/*
* Only works for the first char of the pattern.
*/
break;
flag = 0;
switch (c)
{
case CONTROL('E'): /* ignore END of file */
case '*':
flag = SRCH_PAST_EOF;
break;
case CONTROL('F'): /* FIRST file */
case '@':
flag = SRCH_FIRST_FILE;
break;
case CONTROL('K'): /* KEEP position */
flag = SRCH_NO_MOVE;
break;
case CONTROL('R'): /* Don't use REGULAR EXPRESSIONS */
flag = SRCH_NO_REGEX;
break;
case CONTROL('N'): /* NOT match */
case '!':
flag = SRCH_NO_MATCH;
break;
}
if (flag != 0)
{
search_type ^= flag;
mca_search();
return (MCA_MORE);
}
break;
}
/*
* Any other multicharacter command
* is terminated by a newline.
*/
if (c == '\n' || c == '\r')
{
/*
* Execute the command.
*/
exec_mca();
return (MCA_DONE);
}
/*
* Append the char to the command buffer.
*/
if (cmd_char(c) == CC_QUIT)
/*
* Abort the multi-char command.
*/
return (MCA_DONE);
if ((mca == A_F_BRACKET || mca == A_B_BRACKET) && len_cmdbuf() >= 2)
{
/*
* Special case for the bracket-matching commands.
* Execute the command after getting exactly two
* characters from the user.
*/
exec_mca();
return (MCA_DONE);
}
/*
* Need another character.
*/
return (MCA_MORE);
}
/*
* Make sure the screen is displayed.
*/
static void
make_display()
{
/*
* If nothing is displayed yet, display starting from initial_scrpos.
*/
if (empty_screen())
{
if (initial_scrpos.pos == NULL_POSITION)
/*
* {{ Maybe this should be:
* jump_loc(ch_zero(), jump_sline);
* but this behavior seems rather unexpected
* on the first screen. }}
*/
jump_loc(ch_zero(), 1);
else
jump_loc(initial_scrpos.pos, initial_scrpos.ln);
} else if (screen_trashed)
{
int save_top_scroll;
save_top_scroll = top_scroll;
top_scroll = 1;
repaint();
top_scroll = save_top_scroll;
}
}
/*
* Display the appropriate prompt.
*/
static void
prompt()
{
register char *p;
if (ungotp != NULL && ungotp > ungot)
{
/*
* No prompt necessary if commands are from
* ungotten chars rather than from the user.
*/
return;
}
/*
* Make sure the screen is displayed.
*/
make_display();
bottompos = position(BOTTOM_PLUS_ONE);
/*
* If the -E flag is set and we've hit EOF on the last file, quit.
*/
if ((quit_at_eof == OPT_ONPLUS || quit_if_one_screen) &&
hit_eof && !(ch_getflags() & CH_HELPFILE) &&
next_ifile(curr_ifile) == NULL_IFILE)
quit(QUIT_OK);
quit_if_one_screen = FALSE;
#if 0 /* This doesn't work well because some "te"s clear the screen. */
/*
* If the -e flag is set and we've hit EOF on the last file,
* and the file is squished (shorter than the screen), quit.
*/
if (quit_at_eof && squished &&
next_ifile(curr_ifile) == NULL_IFILE)
quit(QUIT_OK);
#endif
/*
* Select the proper prompt and display it.
*/
clear_cmd();
p = pr_string();
if (p == NULL)
putchr(':');
else
{
so_enter();
putstr(p);
so_exit();
}
}
/*
* Display the less version message.
*/
public void
dispversion()
{
PARG parg;
parg.p_string = version;
error("less %s", &parg);
}
/*
* Get command character.
* The character normally comes from the keyboard,
* but may come from ungotten characters
* (characters previously given to ungetcc or ungetsc).
*/
public int
getcc()
{
if (ungotp == NULL)
/*
* Normal case: no ungotten chars, so get one from the user.
*/
return (getchr());
if (ungotp > ungot)
/*
* Return the next ungotten char.
*/
return (*--ungotp);
/*
* We have just run out of ungotten chars.
*/
ungotp = NULL;
if (len_cmdbuf() == 0 || !empty_screen())
return (getchr());
/*
* Command is incomplete, so try to complete it.
*/
switch (mca)
{
case A_DIGIT:
/*
* We have a number but no command. Treat as #g.
*/
return ('g');
case A_F_SEARCH:
case A_B_SEARCH:
/*
* We have "/string" but no newline. Add the \n.
*/
return ('\n');
default:
/*
* Some other incomplete command. Let user complete it.
*/
return (getchr());
}
}
/*
* "Unget" a command character.
* The next getcc() will return this character.
*/
public void
ungetcc(c)
int c;
{
if (ungotp == NULL)
ungotp = ungot;
if (ungotp >= ungot + sizeof(ungot))
{
error("ungetcc overflow", NULL_PARG);
quit(QUIT_ERROR);
}
*ungotp++ = c;
}
/*
* Unget a whole string of command characters.
* The next sequence of getcc()'s will return this string.
*/
public void
ungetsc(s)
char *s;
{
register char *p;
for (p = s + strlen(s) - 1; p >= s; p--)
ungetcc(*p);
}
/*
* Search for a pattern, possibly in multiple files.
* If SRCH_FIRST_FILE is set, begin searching at the first file.
* If SRCH_PAST_EOF is set, continue the search thru multiple files.
*/
static void
multi_search(pattern, n)
char *pattern;
int n;
{
register int nomore;
IFILE save_ifile;
int changed_file;
changed_file = 0;
save_ifile = save_curr_ifile();
if (search_type & SRCH_FIRST_FILE)
{
/*
* Start at the first (or last) file
* in the command line list.
*/
if (search_type & SRCH_FORW)
nomore = edit_first();
else
nomore = edit_last();
if (nomore)
{
unsave_ifile(save_ifile);
return;
}
changed_file = 1;
search_type &= ~SRCH_FIRST_FILE;
}
for (;;)
{
n = search(search_type, pattern, n);
/*
* The SRCH_NO_MOVE flag doesn't "stick": it gets cleared
* after being used once. This allows "n" to work after
* using a /@@ search.
*/
search_type &= ~SRCH_NO_MOVE;
if (n == 0)
{
/*
* Found it.
*/
unsave_ifile(save_ifile);
return;
}
if (n < 0)
/*
* Some kind of error in the search.
* Error message has been printed by search().
*/
break;
if ((search_type & SRCH_PAST_EOF) == 0)
/*
* We didn't find a match, but we're
* supposed to search only one file.
*/
break;
/*
* Move on to the next file.
*/
if (search_type & SRCH_FORW)
nomore = edit_next(1);
else
nomore = edit_prev(1);
if (nomore)
break;
changed_file = 1;
}
/*
* Didn't find it.
* Print an error message if we haven't already.
*/
if (n > 0)
error("Pattern not found", NULL_PARG);
if (changed_file)
{
/*
* Restore the file we were originally viewing.
*/
reedit_ifile(save_ifile);
}
}
/*
* Main command processor.
* Accept and execute commands until a quit command.
*/
public void
commands()
{
register int c;
register int action;
register char *cbuf;
int newaction;
int save_search_type;
char *extra;
char tbuf[2];
PARG parg;
IFILE old_ifile;
IFILE new_ifile;
search_type = SRCH_FORW;
wscroll = (sc_height + 1) / 2;
newaction = A_NOACTION;
for (;;)
{
mca = 0;
cmd_accept();
number = 0;
optchar = '\0';
/*
* See if any signals need processing.
*/
if (sigs)
{
psignals();
if (quitting)
quit(QUIT_SAVED_STATUS);
}
/*
* See if window size changed, for systems that don't
* generate SIGWINCH.
*/
check_winch();
/*
* Display prompt and accept a character.
*/
cmd_reset();
prompt();
if (sigs)
continue;
if (newaction == A_NOACTION)
c = getcc();
again:
if (sigs)
continue;
if (newaction != A_NOACTION)
{
action = newaction;
newaction = A_NOACTION;
} else
{
/*
* If we are in a multicharacter command, call mca_char.
* Otherwise we call fcmd_decode to determine the
* action to be performed.
*/
if (mca)
switch (mca_char(c))
{
case MCA_MORE:
/*
* Need another character.
*/
c = getcc();
goto again;
case MCA_DONE:
/*
* Command has been handled by mca_char.
* Start clean with a prompt.
*/
continue;
case NO_MCA:
/*
* Not a multi-char command
* (at least, not anymore).
*/
break;
}
/*
* Decode the command character and decide what to do.
*/
if (mca)
{
/*
* We're in a multichar command.
* Add the character to the command buffer
* and display it on the screen.
* If the user backspaces past the start
* of the line, abort the command.
*/
if (cmd_char(c) == CC_QUIT || len_cmdbuf() == 0)
continue;
cbuf = get_cmdbuf();
} else
{
/*
* Don't use cmd_char if we're starting fresh
* at the beginning of a command, because we
* don't want to echo the command until we know
* it is a multichar command. We also don't
* want erase_char/kill_char to be treated
* as line editing characters.
*/
tbuf[0] = c;
tbuf[1] = '\0';
cbuf = tbuf;
}
extra = NULL;
action = fcmd_decode(cbuf, &extra);
/*
* If an "extra" string was returned,
* process it as a string of command characters.
*/
if (extra != NULL)
ungetsc(extra);
}
/*
* Clear the cmdbuf string.
* (But not if we're in the prefix of a command,
* because the partial command string is kept there.)
*/
if (action != A_PREFIX)
cmd_reset();
switch (action)
{
case A_DIGIT:
/*
* First digit of a number.
*/
start_mca(A_DIGIT, ":", (void*)NULL, CF_QUIT_ON_ERASE);
goto again;
case A_F_WINDOW:
/*
* Forward one window (and set the window size).
*/
if (number > 0)
swindow = number;
/* FALLTHRU */
case A_F_SCREEN:
/*
* Forward one screen.
*/
if (number <= 0)
number = get_swindow();
cmd_exec();
if (show_attn)
set_attnpos(bottompos);
forward(number, 0, 1);
break;
case A_B_WINDOW:
/*
* Backward one window (and set the window size).
*/
if (number > 0)
swindow = number;
/* FALLTHRU */
case A_B_SCREEN:
/*
* Backward one screen.
*/
if (number <= 0)
number = get_swindow();
cmd_exec();
backward(number, 0, 1);
break;