From 02d1f6c91a787c58846362179f37451e042de18f Mon Sep 17 00:00:00 2001 From: Elena Zannoni Date: Sun, 9 Jul 2000 16:21:23 +0000 Subject: Initial revision --- readline/examples/excallback.c | 186 +++++++++++ readline/examples/rlfe.c | 685 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 871 insertions(+) create mode 100644 readline/examples/excallback.c create mode 100644 readline/examples/rlfe.c (limited to 'readline/examples') diff --git a/readline/examples/excallback.c b/readline/examples/excallback.c new file mode 100644 index 00000000000..ca03fc3dafd --- /dev/null +++ b/readline/examples/excallback.c @@ -0,0 +1,186 @@ +/* +From: Jeff Solomon +Date: Fri, 9 Apr 1999 10:13:27 -0700 (PDT) +To: chet@po.cwru.edu +Subject: new readline example +Message-ID: <14094.12094.527305.199695@mrclean.Stanford.EDU> + +Chet, + +I've been using readline 4.0. Specifically, I've been using the perl +version Term::ReadLine::Gnu. It works great. + +Anyway, I've been playing around the alternate interface and I wanted +to contribute a little C program, callback.c, to you that you could +use as an example of the alternate interface in the /examples +directory of the readline distribution. + +My example shows how, using the alternate interface, you can +interactively change the prompt (which is very nice imo). Also, I +point out that you must roll your own terminal setting when using the +alternate interface because readline depreps (using your parlance) the +terminal while in the user callback. I try to demostrate what I mean +with an example. I've included the program below. + +To compile, I just put the program in the examples directory and made +the appropriate changes to the EXECUTABLES and OBJECTS line and added +an additional target 'callback'. + +I compiled on my Sun Solaris2.6 box using Sun's cc. + +Let me know what you think. + +Jeff +*/ + +#if defined (HAVE_CONFIG_H) +#include +#endif + +#include +#include + +#ifdef HAVE_UNISTD_H +#include +#endif + +#include /* xxx - should make this more general */ + +#ifdef READLINE_LIBRARY +# include "readline.h" +#else +# include +#endif + +/* This little examples demonstrates the alternate interface to using readline. + * In the alternate interface, the user maintains control over program flow and + * only calls readline when STDIN is readable. Using the alternate interface, + * you can do anything else while still using readline (like talking to a + * network or another program) without blocking. + * + * Specifically, this program highlights two importants features of the + * alternate interface. The first is the ability to interactively change the + * prompt, which can't be done using the regular interface since rl_prompt is + * read-only. + * + * The second feature really highlights a subtle point when using the alternate + * interface. That is, readline will not alter the terminal when inside your + * callback handler. So let's so, your callback executes a user command that + * takes a non-trivial amount of time to complete (seconds). While your + * executing the command, the user continues to type keystrokes and expects them + * to be re-echoed on the new prompt when it returns. Unfortunately, the default + * terminal configuration doesn't do this. After the prompt returns, the user + * must hit one additional keystroke and then will see all of his previous + * keystrokes. To illustrate this, compile and run this program. Type "sleep" at + * the prompt and then type "bar" before the prompt returns (you have 3 + * seconds). Notice how "bar" is re-echoed on the prompt after the prompt + * returns? This is what you expect to happen. Now comment out the 4 lines below + * the line that says COMMENT LINE BELOW. Recompile and rerun the program and do + * the same thing. When the prompt returns, you should not see "bar". Now type + * "f", see how "barf" magically appears? This behavior is un-expected and not + * desired. + */ + +void process_line(char *line); +int change_prompt(void); +char *get_prompt(void); + +int prompt = 1; +char prompt_buf[40], line_buf[256]; +tcflag_t old_lflag; +cc_t old_vtime; +struct termios term; + +int +main() +{ + fd_set fds; + + /* Adjust the terminal slightly before the handler is installed. Disable + * canonical mode processing and set the input character time flag to be + * non-blocking. + */ + if( tcgetattr(STDIN_FILENO, &term) < 0 ) { + perror("tcgetattr"); + exit(1); + } + old_lflag = term.c_lflag; + old_vtime = term.c_cc[VTIME]; + term.c_lflag &= ~ICANON; + term.c_cc[VTIME] = 1; + /* COMMENT LINE BELOW - see above */ + if( tcsetattr(STDIN_FILENO, TCSANOW, &term) < 0 ) { + perror("tcsetattr"); + exit(1); + } + + rl_add_defun("change-prompt", change_prompt, CTRL('t')); + rl_callback_handler_install(get_prompt(), process_line); + + while(1) { + FD_ZERO(&fds); + FD_SET(fileno(stdin), &fds); + + if( select(FD_SETSIZE, &fds, NULL, NULL, NULL) < 0) { + perror("select"); + exit(1); + } + + if( FD_ISSET(fileno(stdin), &fds) ) { + rl_callback_read_char(); + } + } +} + +void +process_line(char *line) +{ + if( line == NULL ) { + fprintf(stderr, "\n", line); + + /* reset the old terminal setting before exiting */ + term.c_lflag = old_lflag; + term.c_cc[VTIME] = old_vtime; + if( tcsetattr(STDIN_FILENO, TCSANOW, &term) < 0 ) { + perror("tcsetattr"); + exit(1); + } + exit(0); + } + + if( strcmp(line, "sleep") == 0 ) { + sleep(3); + } else { + fprintf(stderr, "|%s|\n", line); + } +} + +int +change_prompt(void) +{ + /* toggle the prompt variable */ + prompt = !prompt; + + /* save away the current contents of the line */ + strcpy(line_buf, rl_line_buffer); + + /* install a new handler which will change the prompt and erase the current line */ + rl_callback_handler_install(get_prompt(), process_line); + + /* insert the old text on the new line */ + rl_insert_text(line_buf); + + /* redraw the current line - this is an undocumented function. It invokes the + * redraw-current-line command. + */ + rl_refresh_line(0, 0); +} + +char * +get_prompt(void) +{ + /* The prompts can even be different lengths! */ + sprintf(prompt_buf, "%s", + prompt ? "Hit ctrl-t to toggle prompt> " : "Pretty cool huh?> "); + return prompt_buf; +} diff --git a/readline/examples/rlfe.c b/readline/examples/rlfe.c new file mode 100644 index 00000000000..5c3c8fde45b --- /dev/null +++ b/readline/examples/rlfe.c @@ -0,0 +1,685 @@ +/* A front-end using readline to "cook" input lines for Kawa. + * + * Copyright (C) 1999 Per Bothner + * + * This front-end program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as published + * by the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * Some code from Johnson & Troan: "Linux Application Development" + * (Addison-Wesley, 1998) was used directly or for inspiration. + */ + +/* PROBLEMS/TODO: + * + * Only tested under Linux; needs to be ported. + * + * When running mc -c under the Linux console, mc does not recognize + * mouse clicks, which mc does when not running under fep. + * + * Pasting selected text containing tabs is like hitting the tab character, + * which invokes readline completion. We don't want this. I don't know + * if this is fixable without integrating fep into a terminal emulator. + * + * Echo suppression is a kludge, but can only be avoided with better kernel + * support: We need a tty mode to disable "real" echoing, while still + * letting the inferior think its tty driver to doing echoing. + * Stevens's book claims SCR$ and BSD4.3+ have TIOCREMOTE. + * + * The latest readline may have some hooks we can use to avoid having + * to back up the prompt. + * + * Desirable readline feature: When in cooked no-echo mode (e.g. password), + * echo characters are they are types with '*', but remove them when done. + * + * A synchronous output while we're editing an input line should be + * inserted in the output view *before* the input line, so that the + * lines being edited (with the prompt) float at the end of the input. + * + * A "page mode" option to emulate more/less behavior: At each page of + * output, pause for a user command. This required parsing the output + * to keep track of line lengths. It also requires remembering the + * output, if we want an option to scroll back, which suggests that + * this should be integrated with a terminal emulator like xterm. + */ + +#ifdef HAVE_CONFIG_H +# include +#endif + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef READLINE_LIBRARY +# include "readline.h" +# include "history.h" +#else +# include +# include +#endif + +#ifndef COMMAND +#define COMMAND "/bin/sh" +#endif +#ifndef COMMAND_ARGS +#define COMMAND_ARGS COMMAND +#endif + +#ifndef HAVE_MEMMOVE +# if __GNUC__ > 1 +# define memmove(d, s, n) __builtin_memcpy(d, s, n) +# else +# define memmove(d, s, n) memcpy(d, s, n) +# endif +#else +# define memmove(d, s, n) memcpy(d, s, n) +#endif + +#define APPLICATION_NAME "Fep" + +static int in_from_inferior_fd; +static int out_to_inferior_fd; + +/* Unfortunately, we cannot safely display echo from the inferior process. + The reason is that the echo bit in the pty is "owned" by the inferior, + and if we try to turn it off, we could confuse the inferior. + Thus, when echoing, we get echo twice: First readline echoes while + we're actually editing. Then we send the line to the inferior, and the + terminal driver send back an extra echo. + The work-around is to remember the input lines, and when we see that + line come back, we supress the output. + A better solution (supposedly available on SVR4) would be a smarter + terminal driver, with more flags ... */ +#define ECHO_SUPPRESS_MAX 1024 +char echo_suppress_buffer[ECHO_SUPPRESS_MAX]; +int echo_suppress_start = 0; +int echo_suppress_limit = 0; + +#define DEBUG + +#ifdef DEBUG +FILE *logfile = NULL; +#define DPRINT0(FMT) (fprintf(logfile, FMT), fflush(logfile)) +#define DPRINT1(FMT, V1) (fprintf(logfile, FMT, V1), fflush(logfile)) +#define DPRINT2(FMT, V1, V2) (fprintf(logfile, FMT, V1, V2), fflush(logfile)) +#else +#define DPRINT0(FMT) /* Do nothing */ +#define DPRINT1(FMT, V1) /* Do nothing */ +#define DPRINT2(FMT, V1, V2) /* Do nothing */ +#endif + +struct termios orig_term; + +/* Pid of child process. */ +static pid_t child = -1; + +static void +sig_child (int signo) +{ + int status; + wait (&status); + DPRINT0 ("(Child process died.)\n"); + tcsetattr(STDIN_FILENO, TCSANOW, &orig_term); + exit (0); +} + +volatile int propagate_sigwinch = 0; + +/* sigwinch_handler + * propagate window size changes from input file descriptor to + * master side of pty. + */ +void sigwinch_handler(int signal) { + propagate_sigwinch = 1; +} + +/* get_master_pty() takes a double-indirect character pointer in which + * to put a slave name, and returns an integer file descriptor. + * If it returns < 0, an error has occurred. + * Otherwise, it has returned the master pty file descriptor, and fills + * in *name with the name of the corresponding slave pty. + * Once the slave pty has been opened, you are responsible to free *name. + */ + +int get_master_pty(char **name) { + int i, j; + /* default to returning error */ + int master = -1; + + /* create a dummy name to fill in */ + *name = strdup("/dev/ptyXX"); + + /* search for an unused pty */ + for (i=0; i<16 && master <= 0; i++) { + for (j=0; j<16 && master <= 0; j++) { + (*name)[5] = 'p'; + (*name)[8] = "pqrstuvwxyzPQRST"[i]; + (*name)[9] = "0123456789abcdef"[j]; + /* open the master pty */ + if ((master = open(*name, O_RDWR)) < 0) { + if (errno == ENOENT) { + /* we are out of pty devices */ + free (*name); + return (master); + } + } + else { + /* By substituting a letter, we change the master pty + * name into the slave pty name. + */ + (*name)[5] = 't'; + if (access(*name, R_OK|W_OK) != 0) + { + close(master); + master = -1; + } + } + } + } + if ((master < 0) && (i == 16) && (j == 16)) { + /* must have tried every pty unsuccessfully */ + free (*name); + return (master); + } + + (*name)[5] = 't'; + + return (master); +} + +/* get_slave_pty() returns an integer file descriptor. + * If it returns < 0, an error has occurred. + * Otherwise, it has returned the slave file descriptor. + */ + +int get_slave_pty(char *name) { + struct group *gptr; + gid_t gid; + int slave = -1; + + /* chown/chmod the corresponding pty, if possible. + * This will only work if the process has root permissions. + * Alternatively, write and exec a small setuid program that + * does just this. + */ + if ((gptr = getgrnam("tty")) != 0) { + gid = gptr->gr_gid; + } else { + /* if the tty group does not exist, don't change the + * group on the slave pty, only the owner + */ + gid = -1; + } + + /* Note that we do not check for errors here. If this is code + * where these actions are critical, check for errors! + */ + chown(name, getuid(), gid); + /* This code only makes the slave read/writeable for the user. + * If this is for an interactive shell that will want to + * receive "write" and "wall" messages, OR S_IWGRP into the + * second argument below. + */ + chmod(name, S_IRUSR|S_IWUSR); + + /* open the corresponding slave pty */ + slave = open(name, O_RDWR); + return (slave); +} + +/* Certain special characters, such as ctrl/C, we want to pass directly + to the inferior, rather than letting readline handle them. */ + +static char special_chars[20]; +static int special_chars_count; + +static void +add_special_char(int ch) +{ + if (ch != 0) + special_chars[special_chars_count++] = ch; +} + +static int eof_char; + +static int +is_special_char(int ch) +{ + int i; +#if 0 + if (ch == eof_char && rl_point == rl_end) + return 1; +#endif + for (i = special_chars_count; --i >= 0; ) + if (special_chars[i] == ch) + return 1; + return 0; +} + +static char buf[1024]; +/* buf[0 .. buf_count-1] is the what has been emitted on the current line. + It is used as the readline prompt. */ +static int buf_count = 0; + +int num_keys = 0; + +static void +null_prep_terminal (int meta) +{ +} + +static void +null_deprep_terminal () +{ +} + +char pending_special_char; + +static void +line_handler (char *line) +{ + if (line == NULL) + { + char buf[1]; + DPRINT0("saw eof!\n"); + buf[0] = '\004'; /* ctrl/d */ + write (out_to_inferior_fd, buf, 1); + } + else + { + static char enter[] = "\r"; + /* Send line to inferior: */ + int length = strlen (line); + if (length > ECHO_SUPPRESS_MAX-2) + { + echo_suppress_start = 0; + echo_suppress_limit = 0; + } + else + { + if (echo_suppress_limit + length > ECHO_SUPPRESS_MAX - 2) + { + if (echo_suppress_limit - echo_suppress_start + length + <= ECHO_SUPPRESS_MAX - 2) + { + memmove (echo_suppress_buffer, + echo_suppress_buffer + echo_suppress_start, + echo_suppress_limit - echo_suppress_start); + echo_suppress_limit -= echo_suppress_start; + echo_suppress_start = 0; + } + else + { + echo_suppress_limit = 0; + } + echo_suppress_start = 0; + } + memcpy (echo_suppress_buffer + echo_suppress_limit, + line, length); + echo_suppress_limit += length; + echo_suppress_buffer[echo_suppress_limit++] = '\r'; + echo_suppress_buffer[echo_suppress_limit++] = '\n'; + } + write (out_to_inferior_fd, line, length); + if (pending_special_char == 0) + { + write (out_to_inferior_fd, enter, sizeof(enter)-1); + if (*line) + add_history (line); + } + free (line); + } + rl_callback_handler_remove (); + buf_count = 0; + num_keys = 0; + if (pending_special_char != 0) + { + write (out_to_inferior_fd, &pending_special_char, 1); + pending_special_char = 0; + } +} + +/* Value of rl_getc_function. + Use this because readline should read from stdin, not rl_instream, + points to the pty (so readline has monitor its terminal modes). */ + +int +my_rl_getc (FILE *dummy) +{ + int ch = rl_getc (stdin); + if (is_special_char (ch)) + { + pending_special_char = ch; + return '\r'; + } + return ch; +} + +int +main(int argc, char** argv) +{ + char *path; + int i; + int master; + char *name; + int in_from_tty_fd; + struct sigaction act; + struct winsize ws; + struct termios t; + int maxfd; + fd_set in_set; + static char empty_string[1] = ""; + char *prompt = empty_string; + int ioctl_err = 0; + +#ifdef DEBUG + logfile = fopen("LOG", "w"); +#endif + + rl_readline_name = APPLICATION_NAME; + + if ((master = get_master_pty(&name)) < 0) + { + perror("ptypair: could not open master pty"); + exit(1); + } + + DPRINT1("pty name: '%s'\n", name); + + /* set up SIGWINCH handler */ + act.sa_handler = sigwinch_handler; + sigemptyset(&(act.sa_mask)); + act.sa_flags = 0; + if (sigaction(SIGWINCH, &act, NULL) < 0) + { + perror("ptypair: could not handle SIGWINCH "); + exit(1); + } + + if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) < 0) + { + perror("ptypair: could not get window size"); + exit(1); + } + + if ((child = fork()) < 0) + { + perror("cannot fork"); + exit(1); + } + + if (child == 0) + { + int slave; /* file descriptor for slave pty */ + + /* We are in the child process */ + close(master); + +#ifdef TIOCSCTTY + if ((slave = get_slave_pty(name)) < 0) + { + perror("ptypair: could not open slave pty"); + exit(1); + } + free(name); +#endif + + /* We need to make this process a session group leader, because + * it is on a new PTY, and things like job control simply will + * not work correctly unless there is a session group leader + * and process group leader (which a session group leader + * automatically is). This also disassociates us from our old + * controlling tty. + */ + if (setsid() < 0) + { + perror("could not set session leader"); + } + + /* Tie us to our new controlling tty. */ +#ifdef TIOCSCTTY + if (ioctl(slave, TIOCSCTTY, NULL)) + { + perror("could not set new controlling tty"); + } +#else + if ((slave = get_slave_pty(name)) < 0) + { + perror("ptypair: could not open slave pty"); + exit(1); + } + free(name); +#endif + + /* make slave pty be standard in, out, and error */ + dup2(slave, STDIN_FILENO); + dup2(slave, STDOUT_FILENO); + dup2(slave, STDERR_FILENO); + + /* at this point the slave pty should be standard input */ + if (slave > 2) + { + close(slave); + } + + /* Try to restore window size; failure isn't critical */ + if (ioctl(STDOUT_FILENO, TIOCSWINSZ, &ws) < 0) + { + perror("could not restore window size"); + } + + /* now start the shell */ + { + static char* command_args[] = { COMMAND_ARGS, NULL }; + if (argc <= 1) + execvp(COMMAND, command_args); + else + execvp(argv[1], &argv[1]); + } + + /* should never be reached */ + exit(1); + } + + /* parent */ + signal (SIGCHLD, sig_child); + free(name); + + /* Note that we only set termios settings for standard input; + * the master side of a pty is NOT a tty. + */ + tcgetattr(STDIN_FILENO, &orig_term); + + t = orig_term; + eof_char = t.c_cc[VEOF]; + /* add_special_char(t.c_cc[VEOF]);*/ + add_special_char(t.c_cc[VINTR]); + add_special_char(t.c_cc[VQUIT]); + add_special_char(t.c_cc[VSUSP]); +#if defined (VDISCARD) + add_special_char(t.c_cc[VDISCARD]); +#endif + +#if 0 + t.c_lflag |= (ICANON | ISIG | ECHO | ECHOCTL | ECHOE | \ + ECHOK | ECHOKE | ECHONL | ECHOPRT ); +#else + t.c_lflag &= ~(ICANON | ISIG | ECHO | ECHOCTL | ECHOE | \ + ECHOK | ECHOKE | ECHONL | ECHOPRT ); +#endif + t.c_iflag |= IGNBRK; + t.c_cc[VMIN] = 1; + t.c_cc[VTIME] = 0; + tcsetattr(STDIN_FILENO, TCSANOW, &t); + in_from_inferior_fd = master; + out_to_inferior_fd = master; + rl_instream = fdopen (master, "r"); + rl_getc_function = my_rl_getc; + + rl_prep_term_function = null_prep_terminal; + rl_deprep_term_function = null_deprep_terminal; + rl_callback_handler_install (prompt, line_handler); + + in_from_tty_fd = STDIN_FILENO; + FD_ZERO (&in_set); + maxfd = in_from_inferior_fd > in_from_tty_fd ? in_from_inferior_fd + : in_from_tty_fd; + for (;;) + { + int num; + FD_SET (in_from_inferior_fd, &in_set); + FD_SET (in_from_tty_fd, &in_set); + + num = select(maxfd+1, &in_set, NULL, NULL, NULL); + + if (propagate_sigwinch) + { + struct winsize ws; + if (ioctl (STDIN_FILENO, TIOCGWINSZ, &ws) >= 0) + { + ioctl (master, TIOCSWINSZ, &ws); + } + propagate_sigwinch = 0; + continue; + } + + if (num <= 0) + { + perror ("select"); + exit (-1); + } + if (FD_ISSET (in_from_tty_fd, &in_set)) + { + extern int readline_echoing_p; + struct termios term_master; + int do_canon = 1; + int ioctl_ret; + + DPRINT1("[tty avail num_keys:%d]\n", num_keys); + + /* If we can't get tty modes for the master side of the pty, we + can't handle non-canonical-mode programs. Always assume the + master is in canonical echo mode if we can't tell. */ + ioctl_ret = tcgetattr(master, &term_master); + + if (ioctl_ret >= 0) + { + DPRINT2 ("echo:%d, canon:%d\n", + (term_master.c_lflag & ECHO) != 0, + (term_master.c_lflag & ICANON) != 0); + do_canon = (term_master.c_lflag & ICANON) != 0; + readline_echoing_p = (term_master.c_lflag & ECHO) != 0; + } + else + { + if (ioctl_err == 0) + DPRINT1("tcgetattr on master fd failed: errno = %d\n", errno); + ioctl_err = 1; + } + + if (do_canon == 0 && num_keys == 0) + { + char ch[10]; + int count = read (STDIN_FILENO, ch, sizeof(ch)); + write (out_to_inferior_fd, ch, count); + } + else + { + if (num_keys == 0) + { + int i; + /* Re-install callback handler for new prompt. */ + if (prompt != empty_string) + free (prompt); + prompt = malloc (buf_count + 1); + if (prompt == NULL) + prompt = empty_string; + else + { + memcpy (prompt, buf, buf_count); + prompt[buf_count] = '\0'; + DPRINT1("New prompt '%s'\n", prompt); +#if 0 /* ifdef HAVE_RL_ALREADY_PROMPTED -- doesn't work */ + rl_already_prompted = buf_count > 0; +#else + if (buf_count > 0) + write (1, "\r", 1); +#endif + } + rl_callback_handler_install (prompt, line_handler); + } + num_keys++; + rl_callback_read_char (); + } + } + else /* input from inferior. */ + { + int i; + int count; + int old_count; + if (buf_count > (sizeof(buf) >> 2)) + buf_count = 0; + count = read (in_from_inferior_fd, buf+buf_count, + sizeof(buf) - buf_count); + if (count <= 0) + { + DPRINT0 ("(Connection closed by foreign host.)\n"); + tcsetattr(STDIN_FILENO, TCSANOW, &orig_term); + exit (0); + } + old_count = buf_count; + + /* Look for any pending echo that we need to suppress. */ + while (echo_suppress_start < echo_suppress_limit + && count > 0 + && buf[buf_count] == echo_suppress_buffer[echo_suppress_start]) + { + count--; + buf_count++; + echo_suppress_start++; + } + + /* Write to the terminal anything that was not suppressed. */ + if (count > 0) + write (1, buf + buf_count, count); + + /* Finally, look for a prompt candidate. + * When we get around to going input (from the keyboard), + * we will consider the prompt to be anything since the last + * line terminator. So we need to save that text in the + * initial part of buf. However, anything before the + * most recent end-of-line is not interesting. */ + buf_count += count; +#if 1 + for (i = buf_count; --i >= old_count; ) +#else + for (i = buf_count - 1; i-- >= buf_count - count; ) +#endif + { + if (buf[i] == '\n' || buf[i] == '\r') + { + i++; + memmove (buf, buf+i, buf_count - i); + buf_count -= i; + break; + } + } + DPRINT2("-> i: %d, buf_count: %d\n", i, buf_count); + } + } +} -- cgit v1.2.1