X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=interactive.c;h=64ee9202fc56309769609c3869738a3e8fd5ec65;hp=e69de29bb2d1d6434b8b29ae775ad8c2e48c5391;hb=88c5dc601a5d1b194da3102566a3fb97947a6aee;hpb=408458ad84180244b6a2ac327d13685bfb2b0867

diff --git a/interactive.c b/interactive.c
index e69de29b..64ee9202 100644
--- a/interactive.c
+++ b/interactive.c
@@ -0,0 +1,640 @@
+/*
+ * Copyright (C) 2011-2012 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
+/** \file interactive.c Readline abstraction for interactive sessions. */
+
+#include <regex.h>
+#include <stdbool.h>
+#include <curses.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+#include <sys/ioctl.h>
+#include <assert.h>
+#include <signal.h>
+
+#include "para.h"
+#include "fd.h"
+#include "buffer_tree.h"
+#include "list.h"
+#include "sched.h"
+#include "interactive.h"
+#include "string.h"
+#include "error.h"
+
+struct i9e_private {
+	struct i9e_client_info *ici;
+	FILE *stderr_stream;
+	char empty_line[1000];
+	struct task task;
+	struct btr_node *stdout_btrn;
+	bool line_handler_running;
+	bool input_eof;
+	bool caught_sigint;
+};
+static struct i9e_private i9e_private, *i9ep = &i9e_private;
+
+static bool is_prefix(const char *partial, const char *full, size_t len)
+{
+	if (len == 0)
+		len = strlen(partial);
+	return !strncmp(partial, full, len);
+}
+
+/*
+ * Generator function for command completion. STATE lets us know whether
+ * to start from scratch; without any state (i.e. STATE == 0), then we
+ * start at the top of the list.
+ */
+static char *command_generator(const char *text, int state)
+{
+	static int list_index, len;
+	const char *name;
+	struct i9e_client_info *ici = i9ep->ici;
+
+	rl_attempted_completion_over = 1; /* disable filename completion */
+	/*
+	 * If this is a new word to complete, initialize now. This includes
+	 * saving the length of TEXT for efficiency, and initializing the index
+	 * variable to 0.
+	 */
+	if (state == 0) {
+		list_index = 0;
+		len = strlen(text);
+	}
+	/* Return the next name which partially matches from the command list. */
+	while ((name = ici->completers[list_index].name)) {
+		list_index++;
+		if (is_prefix(text, name, len))
+			return para_strdup(name);
+	}
+	return NULL; /* no names matched */
+}
+
+static void reset_completion_result(struct i9e_completion_result *cr)
+{
+	cr->dont_append_space = false;
+	cr->filename_completion_desired = false;
+	cr->matches = NULL;
+}
+
+static void create_matches(struct i9e_completion_info *ci,
+		struct i9e_completer *completers,
+		struct i9e_completion_result *cr)
+{
+	int i, ret;
+
+	reset_completion_result(cr);
+
+	ret = create_argv(ci->buffer, " ", &ci->argv);
+	if (ret < 0 || !ci->argv[0])
+		return;
+
+	ci->argc = ret;
+	ci->word_num = compute_word_num(ci->buffer, " ", ci->point);
+	for (i = 0; completers[i].name; i++) {
+		if (strcmp(completers[i].name, ci->argv[0]) != 0)
+			continue;
+		completers[i].completer(ci, cr);
+		break;
+	}
+	PARA_DEBUG_LOG("current word: %d (%s)\n", ci->word_num,
+		ci->argv[ci->word_num]);
+	if (cr->matches)
+		for (i = 0; cr->matches[i]; i++)
+			PARA_DEBUG_LOG("match %d: %s\n", i, cr->matches[i]);
+}
+
+static char *completion_generator(const char *word, int state)
+{
+	static int list_index;
+	static char **argv, **matches;
+	struct i9e_completer *completers = i9ep->ici->completers;
+	struct i9e_completion_info ci = {
+		.word = (char *)word,
+		.point = rl_point,
+		.buffer = rl_line_buffer,
+	};
+	struct i9e_completion_result cr = {.matches = NULL};
+
+	if (state != 0)
+		goto out;
+	/* clean up previous matches and set defaults */
+	free(matches);
+	matches = NULL;
+	free_argv(argv);
+	argv = NULL;
+	list_index = 0;
+	rl_completion_append_character = ' ';
+	rl_completion_suppress_append = false;
+	rl_attempted_completion_over = true;
+
+	create_matches(&ci, completers, &cr);
+
+	matches = cr.matches;
+	argv = ci.argv;
+	rl_completion_suppress_append = cr.dont_append_space;
+	rl_attempted_completion_over = !cr.filename_completion_desired;
+out:
+	if (!matches)
+		return NULL;
+	return matches[list_index++];
+}
+
+/*
+ * Attempt to complete on the contents of TEXT. START and END bound the
+ * region of rl_line_buffer that contains the word to complete.  TEXT is
+ * the word to complete.  We can use the entire contents of rl_line_buffer
+ * in case we want to do some simple parsing. Return the array of matches,
+ * or NULL if there aren't any.
+ */
+static char **i9e_completer(const char *text, int start, __a_unused int end)
+{
+	struct i9e_client_info *ici = i9ep->ici;
+
+	if (!ici->completers)
+		return NULL;
+	/* Complete on command names if this is the first word in the line. */
+	if (start == 0)
+		return rl_completion_matches(text, command_generator);
+	return rl_completion_matches(text, completion_generator);
+}
+
+/**
+ * Prepare writing to stdout.
+ *
+ * \param producer The buffer tree node which produces output.
+ *
+ * The i9e subsystem maintains a buffer tree node which may be attached to
+ * another node which generates output (a "producer"). When attached, the i9e
+ * buffer tree node copies the buffers generated by the producer to stdout.
+ *
+ * This function attaches the i9e input queue to an output queue of \a
+ * producer.
+ *
+ * \return Standard.
+ */
+void i9e_attach_to_stdout(struct btr_node *producer)
+{
+	assert(!i9ep->stdout_btrn);
+	i9ep->stdout_btrn = btr_new_node(&(struct btr_node_description)
+		EMBRACE(.name = "interactive_stdout", .parent = producer));
+}
+
+/**
+ * Reset the terminal and save the in-memory command line history.
+ *
+ * This should be called before the caller exits.
+ */
+void i9e_close(void)
+{
+	char *hf = i9ep->ici->history_file;
+
+	rl_deprep_terminal();
+	fprintf(i9ep->stderr_stream, "\n");
+	if (hf)
+		write_history(hf);
+	fclose(i9ep->stderr_stream);
+}
+
+static void wipe_bottom_line(void)
+{
+	fprintf(i9ep->stderr_stream, "\r%s\r", i9ep->empty_line);
+}
+
+static void clear_bottom_line(void)
+{
+	int point;
+	char *text;
+
+	if (rl_point == 0 && rl_end == 0)
+		return wipe_bottom_line();
+	/*
+	 * We might have a multi-line input that needs to be wiped here, so the
+	 * simple printf("\r<space>\r") is insufficient. To workaround this, we
+	 * remove the whole line, redisplay and restore the killed text.
+	 */
+	point = rl_point;
+	text = rl_copy_text(0, rl_end);
+	rl_kill_full_line(0, 0);
+	rl_redisplay();
+	wipe_bottom_line(); /* wipe out the prompt */
+	rl_insert_text(text);
+	rl_point = point;
+}
+
+static bool input_available(void)
+{
+	fd_set rfds;
+	struct timeval tv = {0, 0};
+	int ret;
+
+	FD_ZERO(&rfds);
+	FD_SET(i9ep->ici->fds[0], &rfds);
+	ret = para_select(1, &rfds, NULL, &tv);
+	return ret > 0;
+}
+
+static void i9e_line_handler(char *line)
+{
+	int ret;
+
+	i9ep->line_handler_running = true;
+	ret = i9ep->ici->line_handler(line);
+	i9ep->line_handler_running = false;
+	if (ret < 0)
+		PARA_WARNING_LOG("%s\n", para_strerror(-ret));
+	rl_set_prompt("");
+	if (line) {
+		if (!*line)
+			rl_set_prompt(i9ep->ici->prompt);
+		else
+			add_history(line);
+		free(line);
+	} else {
+		rl_set_prompt("");
+		i9ep->input_eof = true;
+	}
+}
+
+static void i9e_input(void)
+{
+	do {
+		rl_callback_read_char();
+	} while (input_available());
+}
+
+static void i9e_post_select(struct sched *s, struct task *t)
+{
+	int ret;
+	struct btr_node *btrn = i9ep->stdout_btrn;
+	struct i9e_client_info *ici = i9ep->ici;
+	char *buf;
+	size_t sz;
+
+	if (i9ep->input_eof) {
+		t->error = -E_I9E_EOF;
+		return;
+	}
+	if (!btrn) {
+		i9ep->caught_sigint = false;
+		if (FD_ISSET(ici->fds[0], &s->rfds))
+			i9e_input();
+		return;
+	}
+	if (i9ep->caught_sigint)
+		goto rm_btrn;
+	ret = btr_node_status(i9ep->stdout_btrn, 0, BTR_NT_LEAF);
+	if (ret < 0)
+		goto rm_btrn;
+	sz = btr_next_buffer(btrn, &buf);
+	if (sz == 0)
+		goto out;
+	ret = write_nonblock(ici->fds[1], buf, sz);
+	if (ret < 0)
+		goto rm_btrn;
+	btr_consume(btrn, ret);
+	goto out;
+rm_btrn:
+	btr_remove_node(btrn);
+	btr_free_node(btrn);
+	i9ep->stdout_btrn = NULL;
+	rl_set_prompt(i9ep->ici->prompt);
+	rl_forced_update_display();
+out:
+	t->error = 0;
+}
+
+static void i9e_pre_select(struct sched *s, __a_unused struct task *t)
+{
+	int ret;
+
+	if (i9ep->input_eof || i9ep->caught_sigint) {
+		sched_min_delay(s);
+		return;
+	}
+	if (i9ep->stdout_btrn) {
+		ret = btr_node_status(i9ep->stdout_btrn, 0, BTR_NT_LEAF);
+		if (ret < 0) {
+			sched_min_delay(s);
+			return;
+		}
+		if (ret > 0)
+			para_fd_set(i9ep->ici->fds[1], &s->wfds, &s->max_fileno);
+	}
+	/*
+	 * fd[0] might have been reset to blocking mode if our job was moved to
+	 * the background due to CTRL-Z or SIGSTOP, so set the fd back to
+	 * nonblocking mode.
+	 */
+	ret = mark_fd_nonblocking(i9ep->ici->fds[0]);
+	if (ret < 0)
+		PARA_WARNING_LOG("set to nonblock failed: (fd0 %d, %s)\n",
+			i9ep->ici->fds[0], para_strerror(-ret));
+	para_fd_set(i9ep->ici->fds[0], &s->rfds, &s->max_fileno);
+	return;
+}
+
+static void update_winsize(void)
+{
+	struct winsize w;
+	int ret = ioctl(i9ep->ici->fds[2], TIOCGWINSZ, (char *)&w);
+	int num_columns = 80;
+
+	if (ret >= 0) {
+		assert(w.ws_col < sizeof(i9ep->empty_line));
+		num_columns = w.ws_col;
+	}
+	memset(i9ep->empty_line, ' ', num_columns);
+	i9ep->empty_line[num_columns] = '\0';
+}
+
+/**
+ * Register the i9e task and initialize readline.
+ *
+ * \param ici The i9e configuration parameters set by the caller.
+ * \param s The scheduler instance to add the i9e task to.
+ *
+ * The caller must allocate and initialize the structure \a ici points to.
+ *
+ * \return Standard.
+ * \sa \ref register_task().
+ */
+int i9e_open(struct i9e_client_info *ici, struct sched *s)
+{
+	int ret;
+
+	if (!isatty(ici->fds[0]))
+		return -E_I9E_SETUPTERM;
+	ret = mark_fd_nonblocking(ici->fds[0]);
+	if (ret < 0)
+		return ret;
+	ret = mark_fd_nonblocking(ici->fds[1]);
+	if (ret < 0)
+		return ret;
+	i9ep->task.pre_select = i9e_pre_select;
+	i9ep->task.post_select = i9e_post_select;
+	register_task(s, &i9ep->task);
+	rl_readline_name = "para_i9e";
+	rl_basic_word_break_characters = " ";
+	rl_attempted_completion_function = i9e_completer;
+	i9ep->ici = ici;
+	i9ep->stderr_stream = fdopen(ici->fds[2], "w");
+
+	if (ici->history_file)
+		read_history(ici->history_file);
+	update_winsize();
+	rl_callback_handler_install(i9ep->ici->prompt, i9e_line_handler);
+	return 1;
+}
+
+static void reset_line_state(void)
+{
+	if (i9ep->line_handler_running)
+		return;
+	rl_on_new_line();
+	rl_reset_line_state();
+	rl_forced_update_display();
+}
+
+/**
+ * The log function of the i9e subsystem.
+ *
+ * \param ll Severity log level.
+ * \param fmt Printf-like format string.
+ *
+ * This clears the bottom line of the terminal if necessary and writes the
+ * string given by \a fmt to fd[2], where fd[] is the array provided earlier in
+ * \ref i9e_open().
+ */
+__printf_2_3 void i9e_log(int ll, const char* fmt,...)
+{
+	va_list argp;
+
+	if (ll < i9ep->ici->loglevel)
+		return;
+	if (i9ep->line_handler_running == false)
+		clear_bottom_line();
+	va_start(argp, fmt);
+	vfprintf(i9ep->stderr_stream, fmt, argp);
+	va_end(argp);
+	reset_line_state();
+}
+
+/**
+ * Tell i9e that the caller received a signal.
+ *
+ * \param sig_num The number of the signal received.
+ *
+ * Currently the function only cares about \p SIGINT, but this may change.
+ */
+void i9e_signal_dispatch(int sig_num)
+{
+	if (sig_num == SIGINT) {
+		fprintf(i9ep->stderr_stream, "\n");
+		rl_replace_line ("", false /* clear_undo */);
+		reset_line_state();
+		i9ep->caught_sigint = true;
+	}
+}
+
+/**
+ * Wrapper for select(2) which does not restart on interrupts.
+ *
+ * \param n \sa \ref para_select().
+ * \param readfds \sa \ref para_select().
+ * \param writefds \sa \ref para_select().
+ * \param timeout_tv \sa \ref para_select().
+ *
+ * \return \sa \ref para_select().
+ *
+ * The only difference between this function and \ref para_select() is that
+ * \ref i9e_select() returns zero if the select call returned \p EINTR.
+ */
+int i9e_select(int n, fd_set *readfds, fd_set *writefds,
+		struct timeval *timeout_tv)
+{
+	int ret = select(n, readfds, writefds, NULL, timeout_tv);
+
+	if (ret < 0) {
+		if (errno == EINTR)
+			ret = 0;
+		else
+			ret = -ERRNO_TO_PARA_ERROR(errno);
+	}
+	return ret;
+}
+
+/**
+ * Return the possible completions for a given word.
+ *
+ * \param word The word to complete.
+ * \param string_list All possible words in this context.
+ * \param result String list is returned here.
+ *
+ * This function never fails. If no completion was found, a string list of
+ * length zero is returned. In any case, the result must be freed by the caller
+ * using \ref free_argv().
+ *
+ * This function is independent of readline and may be called before
+ * i9e_open().
+ *
+ * return The number of possible completions.
+ */
+int i9e_extract_completions(const char *word, char **string_list,
+		char ***result)
+{
+	char **matches = para_malloc(sizeof(char *));
+	int match_count = 0, matches_len = 1;
+	char **p;
+	int len = strlen(word);
+
+	for (p = string_list; *p; p++) {
+		if (!is_prefix(word, *p, len))
+			continue;
+		match_count++;
+		if (match_count >= matches_len) {
+			matches_len *= 2;
+			matches = para_realloc(matches,
+				matches_len * sizeof(char *));
+		}
+		matches[match_count - 1] = para_strdup(*p);
+	}
+	matches[match_count] = NULL;
+	*result = matches;
+	return match_count;
+}
+
+/**
+ * Return the list of partially matching words.
+ *
+ * \param word The command to complete.
+ * \param completers The array containing all command names.
+ *
+ * This is similar to \ref i9e_extract_completions(), but completes on the
+ * command names in \a completers.
+ *
+ * \return See \ref i9e_extract_completions().
+ */
+char **i9e_complete_commands(const char *word, struct i9e_completer *completers)
+{
+	char **matches;
+	const char *cmd;
+	int i, match_count, len = strlen(word);
+
+	/*
+	 * In contrast to completing against an arbitrary string list, here we
+	 * know all possible completions and expect that there will not be many
+	 * of them. So it should be OK to iterate twice over all commands which
+	 * simplifies the code a bit.
+	 */
+	for (i = 0, match_count = 0; (cmd = completers[i].name); i++) {
+		if (is_prefix(word, cmd, len))
+			match_count++;
+	}
+	matches = para_malloc((match_count + 1) * sizeof(*matches));
+	for (i = 0, match_count = 0; (cmd = completers[i].name); i++)
+		if (is_prefix(word, cmd, len))
+			matches[match_count++] = para_strdup(cmd);
+	matches[match_count] = NULL;
+	return matches;
+}
+
+/**
+ * Complete according to the given options.
+ *
+ * \param opts All available options.
+ * \param ci Information which was passed to the completer.
+ * \param cr Result pointer.
+ *
+ * This convenience helper can be used to complete an option. The array of all
+ * possible options is passed as the first argument. Flags, i.e. options
+ * without an argument, are expected to be listed as strings of type "-X" in \a
+ * opts while options which require an argument should be passed with a
+ * trailing "=" character like "-X=".
+ *
+ * If the word can be uniquely completed to a flag option, an additional space
+ * character is appended to the output. For non-flag options no space character
+ * is appended.
+ */
+void i9e_complete_option(char **opts, struct i9e_completion_info *ci,
+		struct i9e_completion_result *cr)
+{
+	int num_matches;
+
+	num_matches = i9e_extract_completions(ci->word, opts, &cr->matches);
+	if (num_matches == 1) {
+		char *opt = cr->matches[0];
+		char c = opt[strlen(opt) - 1];
+		if (c == '=')
+			cr->dont_append_space = true;
+	}
+}
+
+/**
+ * Print possible completions to stdout.
+ *
+ * \param completers The array of completion functions.
+ *
+ * At the end of the output a line starting with "-o=", followed by the
+ * (possibly empty) list of completion options is printed. Currently, the only
+ * two completion options are "nospace" and "filenames". The former indicates
+ * that no space should be appended even for a unique match while the latter
+ * indicates that usual filename completion should be performed in addition to
+ * the previously printed options.
+ *
+ * \return Standard.
+ */
+int i9e_print_completions(struct i9e_completer *completers)
+{
+	struct i9e_completion_result cr;
+	struct i9e_completion_info ci;
+	char *buf;
+	const char *end, *p;
+	int i, n, ret;
+
+	reset_completion_result(&cr);
+	buf = getenv("COMP_POINT");
+	ci.point = buf? atoi(buf) : 0;
+	ci.buffer = para_strdup(getenv("COMP_LINE"));
+
+	ci.argc = create_argv(ci.buffer, " ", &ci.argv);
+	ci.word_num = compute_word_num(ci.buffer, " ", ci.point);
+
+	end = ci.buffer + ci.point;
+	for (p = end; p > ci.buffer && *p != ' '; p--)
+		; /* nothing */
+	if (*p == ' ')
+		p++;
+
+	n = end - p + 1;
+	ci.word = para_malloc(n + 1);
+	strncpy(ci.word, p, n);
+	ci.word[n] = '\0';
+
+	PARA_DEBUG_LOG("line: %s, point: %d (%c), wordnum: %d, word: %s\n",
+		ci.buffer, ci.point, ci.buffer[ci.point], ci.word_num, ci.word);
+	if (ci.word_num == 0)
+		cr.matches = i9e_complete_commands(ci.word, completers);
+	else
+		create_matches(&ci, completers, &cr);
+	ret = 0;
+	if (cr.matches && cr.matches[0]) {
+		for (i = 0; cr.matches[i]; i++)
+			printf("%s\n", cr.matches[i]);
+		ret = 1;
+	}
+	printf("-o=");
+	if (cr.dont_append_space)
+		printf("nospace");
+	if (cr.filename_completion_desired)
+		printf(",filenames");
+	printf("\n");
+	free_argv(cr.matches);
+	free_argv(ci.argv);
+	free(ci.buffer);
+	free(ci.word);
+	return ret;
+}