Rename to read-quickly2.0

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 482 insertions, 0 deletions

diff --git a/read-quickly.c b/read-quickly.c
new file mode 100644
index 0000000..acd52a6
--- /dev/null
+++ b/read-quickly.c
@@ -0,0 +1,482 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <termios.h>
+#include <unistd.h>
+#include <wchar.h>
+
+
+
+/**
+ * The default word rate.
+ */
+#ifndef DEFAULT_RATE
+# define DEFAULT_RATE  120  /* 2 hz */
+#endif
+
+/**
+ * Delta-value of rate increment and rate decrement.
+ */
+#ifndef RATE_DELTA
+# define RATE_DELTA  10  /* 10/min */
+#endif
+
+
+
+/**
+ * The a word.
+ */
+struct word {
+	/**
+	 * The word.
+	 */
+	const char *word;
+
+	/**
+	 * Should reverse video be applied?
+	 */
+	int reverse_video;
+};
+
+/**
+ * The name of the process.
+ */
+static const char *argv0;
+
+/**
+ * Have the terminal been resized?
+ */
+static volatile sig_atomic_t caught_sigwinch = 1;
+
+/**
+ * Has the timer expired?
+ */
+static volatile sig_atomic_t caught_sigalrm = 0;
+
+/**
+ * The width of the terminal.
+ */
+static size_t width = 80;
+
+/**
+ * The height of the terminal.
+ */
+static size_t height = 30;
+
+/**
+ * The number of words.
+ */
+static size_t word_count = 0;
+
+/**
+ * All loaded words. Refer to `word_count`
+ * for the number of contained words.
+ */
+static struct word *words;
+
+
+
+/**
+ * Signal handler for SIGWINCH.
+ * Invoked when the terminal resizes.
+ */
+static void
+sigwinch(int signo)
+{
+	caught_sigwinch = 1;
+	(void) signo;
+}
+
+
+/**
+ * Signal handler for SIGALRM.
+ * Invoked when the timer expires.
+ */
+static void
+sigalrm(int signo)
+{
+	caught_sigalrm = 1;
+	(void) signo;
+}
+
+
+/**
+ * Get the size of the terminal.
+ */
+static void
+get_terminal_size(void)
+{
+	struct winsize winsize;
+	if (caught_sigwinch) {
+		caught_sigwinch = 0;
+		while (ioctl(STDOUT_FILENO, (unsigned long)TIOCGWINSZ, &winsize) < 0)
+			if (errno != EINTR)
+				return;
+		height = winsize.ws_row;
+		width = winsize.ws_col;
+	}
+}
+
+
+/**
+ * Get the selected word rate by reading
+ * the environment variable READ_QUICKLY_RATE.
+ * 
+ * @return  The rate in words per minute.
+ */
+static long
+get_word_rate(void)
+{
+	char *s;
+	long r;
+
+	errno = 0;
+	s = getenv("READ_QUICKLY_RATE");
+	if (!s || !*s || !isdigit(*s))
+		return DEFAULT_RATE;
+
+	r = strtol(s, &s, 10);
+	if (r <= 0)
+		return DEFAULT_RATE;
+	while (*s == ' ')
+		s++;
+
+	if      (!*s)                      r *= 1;
+	else if (!strcasecmp(s, "wpm"))    r *= 1;
+	else if (!strcasecmp(s, "w/m"))    r *= 1;
+	else if (!strcasecmp(s, "/m"))     r *= 1;
+	else if (!strcasecmp(s, "wpmin"))  r *= 1;
+	else if (!strcasecmp(s, "w/min"))  r *= 1;
+	else if (!strcasecmp(s, "/min"))   r *= 1;
+	else if (!strcasecmp(s, "wps"))    r *= 60;
+	else if (!strcasecmp(s, "w/s"))    r *= 60;
+	else if (!strcasecmp(s, "/s"))     r *= 60;
+	else if (!strcasecmp(s, "wpsec"))  r *= 60;
+	else if (!strcasecmp(s, "w/sec"))  r *= 60;
+	else if (!strcasecmp(s, "/sec"))   r *= 60;
+	else if (!strcasecmp(s, "hz"))     r *= 60;
+	else
+		return DEFAULT_RATE;
+
+	return r;
+}
+
+
+/**
+ * Count the number of character in a string.
+ * 
+ * @param   s  The string.
+ * @return     The number of characters in `s`.
+ */
+static size_t
+display_len(const char *s)
+{
+	size_t r = 0;
+	wchar_t wc;
+	int len, w;
+	for (; *s; s += len) {
+		len = mbtowc(&wc, s, SIZE_MAX);
+		if (len <= 0)
+			break;
+		w = wcwidth(wc);
+		if (w < 0)
+			break;
+		r += (size_t)w;
+	}
+	return r;
+}
+
+
+/**
+ * Load the file and do some preparsing.
+ * 
+ * @param   fd  The file descriptor to the file, -1 to clean up instead.
+ * @return      0 on success, -1 on error.
+ */
+static int
+load_file(int fd)
+{
+	static char *buffer = NULL;
+	size_t ptr = 0;
+	size_t size = 0;
+	void *new;
+	int saved_errno;
+	char *s;
+	char *end;
+	size_t i;
+	ssize_t n;
+
+	if (fd == -1)
+		return free(buffer), 0;
+
+	/* Load file. */
+	for (;;) {
+		if (ptr == size) {
+			size = size ? size << 1 : 8 << 10;
+			new = realloc(buffer, size);
+			if (!new)
+				goto fail;
+			buffer = new;
+		}
+		n = read(fd, buffer + ptr, size - ptr);
+		if (n <= 0) {
+			if (!n)
+				break;
+			if (errno == EINTR)
+				continue;
+			goto fail;
+		}
+		ptr += (size_t)n;
+	}
+	if (!buffer)
+		return 0;
+	new = realloc(buffer, ptr + 2);
+	if (!new)
+		goto fail;
+	buffer = new;
+	buffer[ptr++] = '\0';
+	buffer[ptr++] = '\0';
+
+	/* Split words. */
+	size = 0;
+	for (s = buffer; *s; s = &end[1]) {
+		if (word_count == size) {
+			size = size ? size << 1 : 512;
+			new = realloc(words, size * sizeof(*words));
+			if (!new)
+				goto fail;
+			words = new;
+		}
+		while (isspace(*s))
+			s++;
+		end = strpbrk(s, " \f\n\r\t\v");
+		if (!end)
+			end = strchr(s, '\0');
+		*end = '\0';
+		words[word_count].word = s;
+		words[word_count].reverse_video = 0;
+		word_count++;
+	}
+
+	/* Figure out which words should have reverse video. */
+	for (i = 1; i < word_count; i++)
+		if (!strcmp(words[i].word, words[i - 1].word))
+			words[i].reverse_video = words[i - 1].reverse_video ^ 1;
+
+	return 0;
+
+fail:
+	saved_errno = errno;
+	free(buffer);
+	buffer = NULL;
+	errno = saved_errno;
+	return -1;
+}
+
+
+/**
+ * Display a file word by word.
+ * 
+ * @param   ttyfd  File descriptor for reading from the terminal.
+ * @param   rate   The number of words per minute to display.
+ * @return         0 on success, -1 on error.
+ */
+static int
+display_file(int ttyfd, long rate)
+{
+#define SET_RATE \
+	(interval.it_value.tv_usec = 60000000L / rate, \
+	 interval.it_value.tv_sec = interval.it_value.tv_usec / 1000000L, \
+	 interval.it_value.tv_usec %= 1000000L)
+
+	ssize_t n;
+	int timer_set = 1;
+	char c;
+	size_t i;
+	struct itimerval interval;
+
+	memset(&interval, 0, sizeof(interval));
+
+	SET_RATE;
+	for (i = 0; i < word_count; i++) {
+		if (setitimer(ITIMER_REAL, &interval, NULL))
+			goto fail;
+	rewait:
+		n = read(ttyfd, &c, sizeof(c));
+		if (n < 0) {
+			if (errno != EINTR)
+				goto fail;
+			c = 0;
+		} else if (n == 0) {
+			break;
+		}
+		switch (c) {
+		case '+': /* plus */
+		case '-': /* hyphen */
+			rate += c == '+' ? RATE_DELTA : -RATE_DELTA;
+			rate = rate <= 0 ? 1 : rate;
+			SET_RATE;
+			goto rewait;
+		case 'p': /* P */
+			if (timer_set)
+				memset(&interval, 0, sizeof(interval));
+			else
+				SET_RATE;
+			if (setitimer(ITIMER_REAL, &interval, NULL))
+				goto fail;
+			timer_set ^= 1;
+			goto rewait;
+		case 'q': /* Q */
+			goto done;
+		case 'B': /* down */
+		case 'C': /* right */
+			break;
+		case 'A': /* up */
+		case 'D': /* left */
+			i = i < 2 ? 0 : i - 2;
+			break;
+		case 0:
+			if (!caught_sigalrm)
+				goto rewait;
+			caught_sigalrm = 0;
+			break;
+		default:
+			goto rewait;
+		}
+
+		get_terminal_size();
+		if (fprintf(stdout, "\033[H\033[2J\033[%zu;%zuH%s%s%s",
+		            (height + 1) / 2,
+		            (width - display_len(words[i].word)) / 2 + 1,
+		            words[i].reverse_video ? "\033[7m" : "",
+		            words[i].word,
+		            words[i].reverse_video ? "\033[27m" : "") < 0)
+			goto fail;
+		if (fflush(stdout))
+			goto fail;
+	}
+
+	if (setitimer(ITIMER_REAL, &interval, NULL))
+		goto fail;
+	(void) read(ttyfd, &c, sizeof(c));
+
+done:
+	return 0;
+
+fail:
+	return -1;
+}
+
+
+int
+main(int argc, char *argv[])
+{
+	long rate = get_word_rate();
+	int fd = -1, ttyfd = -1, tty_configured = 0;
+	struct termios stty, saved_stty;
+	struct stat _attr;
+	struct sigaction sa;
+
+	/* Parse arguments. */
+	argv0 = argv ? (argc--, *argv++) : "read-quickly";
+	if (argc && argv[0][0] == '-') {
+		if (argv[0][1] == '-' && !argv[0][2]) {
+			argc--;
+			argv++;
+		} else if (argv[0][1]) {
+			goto usage;
+		}
+	}
+	if (argc > 1)
+		goto usage;
+
+	/* Check that we have a stdout. */
+	if (fstat(STDOUT_FILENO, &_attr))
+		if (errno == EBADF)
+			goto fail;
+
+	/* Open file. */
+	if (argc && strcmp(*argv, "-")) {
+		fd = open(*argv, O_RDONLY);
+		if (fd < 0)
+			goto fail;
+	} else {
+		fd = STDIN_FILENO;
+	}
+
+	/* Load file. */
+	if (load_file(fd))
+		goto fail;
+
+	/* We do not need the file anymore. */
+	close(fd);
+	fd = -1;
+
+	/* Get a readable file descriptor for the controlling terminal. */
+	ttyfd = open("/dev/tty", O_RDONLY);
+	if (ttyfd < 0)
+		goto fail;
+
+	/* Configure terminal. */
+	if (fprintf(stdout, "\033[?1049h\033[?25l") < 0)
+		goto fail;
+	if (fflush(stdout))
+		goto fail;
+	if (tcgetattr(ttyfd, &stty))
+		goto fail;
+	saved_stty = stty;
+	stty.c_lflag &= (tcflag_t)~(ICANON | ECHO | ISIG);
+	if (tcsetattr(ttyfd, TCSAFLUSH, &stty))
+		goto fail;
+	tty_configured = 1;
+
+	/* Display file. */
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = sigalrm;
+	sigaction(SIGALRM, &sa, NULL);
+	sa.sa_handler = sigwinch;
+	sigaction(SIGWINCH, &sa, NULL);
+	if (display_file(ttyfd, rate))
+		goto fail;
+
+	/* Restore terminal configurations. */
+	tcsetattr(ttyfd, TCSAFLUSH, &saved_stty);
+	fprintf(stdout, "\033[?25h\033[?1049l");
+	fflush(stdout);
+	tty_configured = 0;
+
+	free(words);
+	load_file(-1);
+	close(ttyfd);
+	return 0;
+
+fail:
+	perror(argv0);
+	free(words);
+	load_file(-1);
+	if (tty_configured) {
+		tcsetattr(ttyfd, TCSAFLUSH, &saved_stty);
+		fprintf(stdout, "\033[?25h\033[?1049l");
+		fflush(stdout);
+	}
+	if (fd >= 0)
+		close(fd);
+	if (ttyfd >= 0)
+		close(ttyfd);
+	return 1;
+
+usage:
+	fprintf(stderr, "usage: %s [file].\n", argv0);
+	return 1;
+}