diff options
Diffstat (limited to 'lsystem.c')
| -rwxr-xr-x | lsystem.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/lsystem.c b/lsystem.c new file mode 100755 index 0000000..674e5a2 --- /dev/null +++ b/lsystem.c @@ -0,0 +1,373 @@ +/* + * 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 |