diff options
Diffstat (limited to 'usr.bin/less/lsystem.c')
| -rw-r--r-- | usr.bin/less/lsystem.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/usr.bin/less/lsystem.c b/usr.bin/less/lsystem.c new file mode 100644 index 00000000000..db0e4fca2fd --- /dev/null +++ b/usr.bin/less/lsystem.c @@ -0,0 +1,300 @@ +/* + * Copyright (c) 1984,1985,1989,1994,1995 Mark Nudelman + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice in the documentation and/or other materials provided with + * the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + + +/* + * Routines to execute other programs. + * Necessarily very OS dependent. + */ + +#include <signal.h> +#include "less.h" +#include "position.h" + +#if MSOFTC +#include <dos.h> +#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) + char *cmd; +{ + register int inp; +#if MSOFTC || OS2 + register int inp2; +#endif + register char *shell; + register char *p; + IFILE save_ifile; + + /* + * 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"); + } + + /* + * Close the current input file. + */ + save_ifile = 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); + + /* + * Restore signals to their defaults. + */ + init_signals(0); + + /* + * 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 (OPEN_TTYIN() < 0) + dup(inp); + + /* + * 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 = getenv("SHELL")) != NULL && *shell != '\0') + { + if (*cmd == '\0') + p = save(shell); + else + { + p = (char *) ecalloc(strlen(shell) + strlen(cmd) + 7, + sizeof(char)); + sprintf(p, "%s -c \"%s\"", shell, cmd); + } + } + if (p == NULL) + { + if (*cmd == '\0') + p = save("sh"); + else + p = save(cmd); + } + + system(p); + free(p); +#else +#if OS2 + if (*cmd == '\0') + cmd = "cmd.exe"; +#endif + system(cmd); +#endif + + /* + * Restore standard input, reset signals, raw mode, etc. + */ + close(0); + dup(inp); + close(inp); + + init_signals(1); + raw_mode(1); + init(); + screen_trashed = 1; + + /* + * Reopen the current input file. + */ + if (edit_ifile(save_ifile)) + quit(QUIT_ERROR); + +#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. + * + * The "current" position means the top line displayed if the mark + * is after the current screen, or the bottom line displayed if + * the mark is before the current screen. + * If the mark is on the current screen, the whole screen is displayed. + */ + 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, tpos)); + 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); +#ifdef SIGPIPE + SIGNAL(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 + SIGNAL(SIGPIPE, SIG_DFL); +#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 |