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mirror of https://git.FreeBSD.org/src.git synced 2024-12-25 11:37:56 +00:00
freebsd/contrib/less/lsystem.c
2012-07-24 01:09:11 +00:00

374 lines
7.1 KiB
C

/*
* Copyright (C) 1984-2012 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, see the README file.
*/
/*
* Routines to execute other programs.
* Necessarily very OS dependent.
*/
#include "less.h"
#include <signal.h>
#include "position.h"
#if MSDOS_COMPILER
#include <dos.h>
#ifdef _MSC_VER
#include <direct.h>
#define setdisk(n) _chdrive((n)+1)
#else
#include <dir.h>
#endif
#endif
extern int screen_trashed;
extern IFILE curr_ifile;
#if HAVE_SYSTEM
/*
* Pass the specified command to a shell to be executed.
* Like plain "system()", but handles resetting terminal modes, etc.
*/
public void
lsystem(cmd, donemsg)
char *cmd;
char *donemsg;
{
register int inp;
#if HAVE_SHELL
register char *shell;
register char *p;
#endif
IFILE save_ifile;
#if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C
char cwd[FILENAME_MAX+1];
#endif
/*
* Print the command which is to be executed,
* unless the command starts with a "-".
*/
if (cmd[0] == '-')
cmd++;
else
{
clear_bot();
putstr("!");
putstr(cmd);
putstr("\n");
}
#if MSDOS_COMPILER
#if MSDOS_COMPILER==WIN32C
if (*cmd == '\0')
cmd = getenv("COMSPEC");
#else
/*
* Working directory is global on MSDOS.
* The child might change the working directory, so we
* must save and restore CWD across calls to "system",
* or else we won't find our file when we return and
* try to "reedit_ifile" it.
*/
getcwd(cwd, FILENAME_MAX);
#endif
#endif
/*
* Close the current input file.
*/
save_ifile = save_curr_ifile();
(void) edit_ifile(NULL_IFILE);
/*
* De-initialize the terminal and take out of raw mode.
*/
deinit();
flush(); /* Make sure the deinit chars get out */
raw_mode(0);
#if MSDOS_COMPILER==WIN32C
close_getchr();
#endif
/*
* Restore signals to their defaults.
*/
init_signals(0);
#if HAVE_DUP
/*
* Force standard input to be the user's terminal
* (the normal standard input), even if less's standard input
* is coming from a pipe.
*/
inp = dup(0);
close(0);
#if OS2
/* The __open() system call translates "/dev/tty" to "con". */
if (__open("/dev/tty", OPEN_READ) < 0)
#else
if (open("/dev/tty", OPEN_READ) < 0)
#endif
dup(inp);
#endif
/*
* Pass the command to the system to be executed.
* If we have a SHELL environment variable, use
* <$SHELL -c "command"> instead of just <command>.
* If the command is empty, just invoke a shell.
*/
#if HAVE_SHELL
p = NULL;
if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
{
if (*cmd == '\0')
p = save(shell);
else
{
char *esccmd = shell_quote(cmd);
if (esccmd != NULL)
{
int len = strlen(shell) + strlen(esccmd) + 5;
p = (char *) ecalloc(len, sizeof(char));
SNPRINTF3(p, len, "%s %s %s", shell, shell_coption(), esccmd);
free(esccmd);
}
}
}
if (p == NULL)
{
if (*cmd == '\0')
p = save("sh");
else
p = save(cmd);
}
system(p);
free(p);
#else
#if MSDOS_COMPILER==DJGPPC
/*
* Make stdin of the child be in cooked mode.
*/
setmode(0, O_TEXT);
/*
* We don't need to catch signals of the child (it
* also makes trouble with some DPMI servers).
*/
__djgpp_exception_toggle();
system(cmd);
__djgpp_exception_toggle();
#else
system(cmd);
#endif
#endif
#if HAVE_DUP
/*
* Restore standard input, reset signals, raw mode, etc.
*/
close(0);
dup(inp);
close(inp);
#endif
#if MSDOS_COMPILER==WIN32C
open_getchr();
#endif
init_signals(1);
raw_mode(1);
if (donemsg != NULL)
{
putstr(donemsg);
putstr(" (press RETURN)");
get_return();
putchr('\n');
flush();
}
init();
screen_trashed = 1;
#if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C
/*
* Restore the previous directory (possibly
* changed by the child program we just ran).
*/
chdir(cwd);
#if MSDOS_COMPILER != DJGPPC
/*
* Some versions of chdir() don't change to the drive
* which is part of CWD. (DJGPP does this in chdir.)
*/
if (cwd[1] == ':')
{
if (cwd[0] >= 'a' && cwd[0] <= 'z')
setdisk(cwd[0] - 'a');
else if (cwd[0] >= 'A' && cwd[0] <= 'Z')
setdisk(cwd[0] - 'A');
}
#endif
#endif
/*
* Reopen the current input file.
*/
reedit_ifile(save_ifile);
#if defined(SIGWINCH) || defined(SIGWIND)
/*
* Since we were ignoring window change signals while we executed
* the system command, we must assume the window changed.
* Warning: this leaves a signal pending (in "sigs"),
* so psignals() should be called soon after lsystem().
*/
winch(0);
#endif
}
#endif
#if PIPEC
/*
* Pipe a section of the input file into the given shell command.
* The section to be piped is the section "between" the current
* position and the position marked by the given letter.
*
* If the mark is after the current screen, the section between
* the top line displayed and the mark is piped.
* If the mark is before the current screen, the section between
* the mark and the bottom line displayed is piped.
* If the mark is on the current screen, or if the mark is ".",
* the whole current screen is piped.
*/
public int
pipe_mark(c, cmd)
int c;
char *cmd;
{
POSITION mpos, tpos, bpos;
/*
* mpos = the marked position.
* tpos = top of screen.
* bpos = bottom of screen.
*/
mpos = markpos(c);
if (mpos == NULL_POSITION)
return (-1);
tpos = position(TOP);
if (tpos == NULL_POSITION)
tpos = ch_zero();
bpos = position(BOTTOM);
if (c == '.')
return (pipe_data(cmd, tpos, bpos));
else if (mpos <= tpos)
return (pipe_data(cmd, mpos, bpos));
else if (bpos == NULL_POSITION)
return (pipe_data(cmd, tpos, bpos));
else
return (pipe_data(cmd, tpos, mpos));
}
/*
* Create a pipe to the given shell command.
* Feed it the file contents between the positions spos and epos.
*/
public int
pipe_data(cmd, spos, epos)
char *cmd;
POSITION spos;
POSITION epos;
{
register FILE *f;
register int c;
extern FILE *popen();
/*
* This is structured much like lsystem().
* Since we're running a shell program, we must be careful
* to perform the necessary deinitialization before running
* the command, and reinitialization after it.
*/
if (ch_seek(spos) != 0)
{
error("Cannot seek to start position", NULL_PARG);
return (-1);
}
if ((f = popen(cmd, "w")) == NULL)
{
error("Cannot create pipe", NULL_PARG);
return (-1);
}
clear_bot();
putstr("!");
putstr(cmd);
putstr("\n");
deinit();
flush();
raw_mode(0);
init_signals(0);
#if MSDOS_COMPILER==WIN32C
close_getchr();
#endif
#ifdef SIGPIPE
LSIGNAL(SIGPIPE, SIG_IGN);
#endif
c = EOI;
while (epos == NULL_POSITION || spos++ <= epos)
{
/*
* Read a character from the file and give it to the pipe.
*/
c = ch_forw_get();
if (c == EOI)
break;
if (putc(c, f) == EOF)
break;
}
/*
* Finish up the last line.
*/
while (c != '\n' && c != EOI )
{
c = ch_forw_get();
if (c == EOI)
break;
if (putc(c, f) == EOF)
break;
}
pclose(f);
#ifdef SIGPIPE
LSIGNAL(SIGPIPE, SIG_DFL);
#endif
#if MSDOS_COMPILER==WIN32C
open_getchr();
#endif
init_signals(1);
raw_mode(1);
init();
screen_trashed = 1;
#if defined(SIGWINCH) || defined(SIGWIND)
/* {{ Probably don't need this here. }} */
winch(0);
#endif
return (0);
}
#endif