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/*-
* Copyright (c) 2013-2014 Devin Teske <dteske@FreeBSD.org>
* 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, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <limits.h>
#include <spawn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <unistd.h>
#include "dialog_util.h"
#include "dpv.h"
#include "dpv_private.h"
extern char **environ;
#define TTY_DEFAULT_ROWS 24
#define TTY_DEFAULT_COLS 80
/* [X]dialog(1) characteristics */
uint8_t dialog_test = 0;
uint8_t use_dialog = 0;
uint8_t use_libdialog = 1;
uint8_t use_xdialog = 0;
uint8_t use_color = 1;
char dialog[PATH_MAX] = DIALOG;
/* [X]dialog(1) functionality */
int dheight = 0;
int dwidth = 0;
char *title = NULL;
char *backtitle = NULL;
/* TTY/Screen characteristics */
static struct winsize *maxsize = NULL;
/* Function prototypes for private functions (see style(9)) */
void tty_maxsize_update(void);
void x11_maxsize_update(void);
/*
* Update row/column fields of `maxsize' global (used by dialog_maxrows() and
* dialog_maxcols()). If the `maxsize' pointer is NULL, it will be initialized.
* The `ws_row' and `ws_col' fields of `maxsize' are updated to hold current
* maximum height and width (respectively) for a dialog(1) widget based on the
* active TTY size.
*
* This function is called automatically by dialog_maxrows/cols() to reflect
* changes in terminal size in-between calls.
*/
void
tty_maxsize_update(void)
{
int fd = STDIN_FILENO;
struct termios t;
if (maxsize == NULL)
{
if ((maxsize = malloc(sizeof(struct winsize))) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
memset((void *)maxsize, '\0', sizeof(struct winsize));
}
if (!isatty(fd)) fd = open("/dev/tty", O_RDONLY);
if ((tcgetattr(fd, &t) < 0) || (ioctl(fd, TIOCGWINSZ, maxsize) < 0))
{
maxsize->ws_row = TTY_DEFAULT_ROWS;
maxsize->ws_col = TTY_DEFAULT_COLS;
}
}
/*
* Update row/column fields of `maxsize' global (used by dialog_maxrows() and
* dialog_maxcols()). If the `maxsize' pointer is NULL, it will be initialized.
* The `ws_row' and `ws_col' fields of `maxsize' are updated to hold current
* maximum height and width (respectively) for an Xdialog(1) widget based on
* the active video resolution of the X11 environment.
*
* This function is called automatically by dialog_maxrows/cols() to initialize
* `maxsize'. Since video resolution changes are less common and more obtrusive
* than changes to terminal size, the dialog_maxrows/cols() functions only call
* this function when `maxsize' is set to NULL.
*/
void
x11_maxsize_update(void)
{
FILE *f = NULL;
char *cp, *rows, *cols;
char cmdbuf[LINE_MAX], rbuf[LINE_MAX];
if (maxsize == NULL)
{
if ((maxsize = malloc(sizeof(struct winsize))) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
memset((void *)maxsize, '\0', sizeof(struct winsize));
}
/* Assemble the command necessary to get X11 sizes */
snprintf(cmdbuf, LINE_MAX, "%s --print-maxsize 2>&1", dialog);
fflush(STDIN_FILENO); /* prevent popen(3) from seeking on stdin */
if ((f = popen(cmdbuf, "r")) == NULL)
{
if (debug) warnx("WARNING! Command `%s' failed", cmdbuf);
return;
}
/* Read in the line returned from Xdialog(1) */
if ((fgets(rbuf, LINE_MAX, f) == NULL) || (pclose(f) < 0)) return;
/* Check for X11-related errors */
if (strncmp(rbuf, "Xdialog: Error", 14) == 0) return;
/* Parse expected output: MaxSize: YY, XXX */
if ((rows = strchr(rbuf, ' ')) == NULL) return;
if ((cols = strchr(rows, ',')) != NULL)
{
/* strtonum(3) doesn't like trailing junk */
*(cols++) = '\0';
if ((cp = strchr(cols, '\n')) != NULL) *cp = '\0';
}
/* Convert to unsigned short */
maxsize->ws_row = (unsigned short)strtonum(
rows, 0, USHRT_MAX, (const char **)NULL);
maxsize->ws_col = (unsigned short)strtonum(
cols, 0, USHRT_MAX, (const char **)NULL);
}
/*
* Return the current maximum height (rows) for an [X]dialog(1) widget.
*/
int
dialog_maxrows(void)
{
if (use_xdialog && maxsize == NULL)
x11_maxsize_update(); /* initialize maxsize for GUI */
else if (!use_xdialog)
tty_maxsize_update(); /* update maxsize for TTY */
return maxsize->ws_row;
}
/*
* Return the current maximum width (cols) for an [X]dialog(1) widget.
*/
int
dialog_maxcols(void)
{
if (use_xdialog && maxsize == NULL)
x11_maxsize_update(); /* initialize maxsize for GUI */
else if (!use_xdialog)
tty_maxsize_update(); /* update maxsize for TTY */
if (use_dialog || use_libdialog) {
if (use_shadow)
return (maxsize->ws_col - 2);
else
return (maxsize->ws_col);
} else
return (maxsize->ws_col);
}
/*
* Return the current maximum width (cols) for the terminal.
*/
int
tty_maxcols(void)
{
if (use_xdialog && maxsize == NULL)
x11_maxsize_update(); /* initialize maxsize for GUI */
else if (!use_xdialog)
tty_maxsize_update(); /* update maxsize for TTY */
return (maxsize->ws_col);
}
/*
* Spawn an [X]dialog(1) `--gauge' box with a `--prompt' value of init_prompt.
* Writes the resulting process ID to the pid_t pointed at by `pid'. Returns a
* file descriptor (int) suitable for writing data to the [X]dialog(1) instance
* (data written to the file descriptor is seen as standard-in by the spawned
* [X]dialog(1) process).
*/
int
dialog_spawn_gauge(char *init_prompt, pid_t *pid)
{
unsigned int n = 0;
int height, width, error, stdin_pipe[2] = { -1, -1 };
char *cp, *dargv[13], dummy_init[2] = "";
posix_spawn_file_actions_t action;
/* Override `dialog' with a path from ENV_DIALOG if provided */
if ((cp = getenv(ENV_DIALOG)) != NULL)
snprintf(dialog, PATH_MAX, "%s", cp);
/* For Xdialog(1), set ENV_XDIALOG_HIGH_DIALOG_COMPAT */
setenv(ENV_XDIALOG_HIGH_DIALOG_COMPAT, "1", 1);
/* Constrain the height/width */
height = dialog_maxrows();
if (backtitle != NULL) height -= (use_shadow ? 5 : 4);
if (dheight < height) height = dheight;
width = dialog_maxcols();
if (dwidth < width) width = dwidth;
/* Populate argument array */
dargv[n++] = dialog;
if (title != NULL)
{
if ((dargv[n] = malloc(8)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--title");
dargv[n++] = title;
}
if (backtitle != NULL)
{
if ((dargv[n] = malloc(12)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--backtitle");
dargv[n++] = backtitle;
}
if (use_color)
{
if ((dargv[n] = malloc(11)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--colors");
}
if (use_xdialog)
{
if ((dargv[n] = malloc(7)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--left");
/*
* NOTE: Xdialog(1)'s `--wrap' appears to be broken for the
* `--gauge' widget prompt-updates. Add it anyway (in-case it
* gets fixed in some later release).
*/
if ((dargv[n] = malloc(7)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--wrap");
}
if ((dargv[n] = malloc(8)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
sprintf(dargv[n++], "--gauge");
dargv[n++] = (use_xdialog ? dummy_init : init_prompt);
if ((dargv[n] = malloc(40)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
snprintf(dargv[n++], 40, "%u", height);
if ((dargv[n] = malloc(40)) == NULL)
errx(EXIT_FAILURE, "Out of memory?!");
snprintf(dargv[n++], 40, "%u", width);
dargv[n] = NULL;
/* Open a pipe(2) to communicate with [X]dialog(1) */
if (pipe(stdin_pipe) < 0) err(EXIT_FAILURE, "%s: pipe(2)", __func__);
/* Fork [X]dialog(1) process */
#if DIALOG_SPAWN_DEBUG
{
unsigned int i;
fprintf(stderr, "%s: spawning `", __func__);
for (i = 0; i < n; i++)
{
if (i == 0)
fprintf(stderr, "%s", dargv[i]);
else if (*dargv[i] == '-' && *(dargv[i] + 1) == '-')
fprintf(stderr, " %s", dargv[i]);
else
fprintf(stderr, " \"%s\"", dargv[i]);
}
fprintf(stderr, "'\n");
}
#endif
posix_spawn_file_actions_init(&action);
posix_spawn_file_actions_adddup2(&action, stdin_pipe[0], STDIN_FILENO);
posix_spawn_file_actions_addclose(&action, stdin_pipe[1]);
error = posix_spawnp(pid, dialog, &action,
(const posix_spawnattr_t *)NULL, dargv, environ);
if (error != 0) err(EXIT_FAILURE, "%s: posix_spawnp(3)", __func__);
/* NB: Do not free(3) *dargv[], else SIGSEGV */
return stdin_pipe[1];
}
/*
* Returns the number of lines in buffer pointed to by `prompt'. Takes both
* newlines and escaped-newlines into account.
*/
unsigned int
dialog_prompt_numlines(const char *prompt, uint8_t nlstate)
{
uint8_t nls = nlstate; /* See dialog_prompt_nlstate() */
const char *cp = prompt;
unsigned int nlines = 1;
if (prompt == NULL || *prompt == '\0') return 0;
while (*cp != '\0')
{
if (use_dialog) {
if (strncmp(cp, "\\n", 2) == 0) {
cp++;
nlines++;
nls = 1; /* See declaration comment */
} else if (*cp == '\n') {
if (!nls) nlines++;
nls = 0; /* See declaration comment */
}
} else if (use_libdialog) {
if (*cp == '\n') nlines++;
} else if (strncmp(cp, "\\n", 2) == 0) {
cp++;
nlines++;
}
cp++;
}
return nlines;
}
/*
* Returns the length in bytes of the longest line in buffer pointed to by
* `prompt'. Takes newlines and escaped newlines into account. Also discounts
* dialog(1) color escape codes if enabled (via `use_color' global).
*/
unsigned int
dialog_prompt_longestline(const char *prompt, uint8_t nlstate)
{
uint8_t backslash = 0;
uint8_t nls = nlstate; /* See dialog_prompt_nlstate() */
int n = 0, longest = 0;
const char *p = prompt;
/* `prompt' parameter is required */
if (prompt == NULL) return 0;
if (*prompt == '\0') return 0; /* shortcut */
/* Loop until the end of the string */
while (*p != '\0')
{
/* dialog(1) and dialog(3) will render literal newlines */
if (use_dialog || use_libdialog) {
if (*p == '\n') {
if (!use_libdialog && nls) n++;
else {
if (n > longest) longest = n;
n = 0;
}
nls = 0; /* See declaration comment */
p++;
continue;
}
}
/* Check for backslash character */
if (*p == '\\') {
/* If second backslash, count as a single-char */
if ((backslash ^= 1) == 0) n++;
} else if (backslash) {
if (*p == 'n' && !use_libdialog) { /* new line */
/* NB: dialog(3) ignores escaped newlines */
nls = 1; /* See declaration comment */
if (n > longest) longest = n;
n = 0;
} else if (use_color && *p == 'Z') {
if (*++p != '\0') p++;
backslash = 0;
continue;
} else /* [X]dialog(1)/dialog(3) only expand those */
n += 2;
backslash = 0;
} else
n++;
p++;
}
if (n > longest) longest = n;
return longest;
}
/*
* Returns a pointer to the last line in buffer pointed to by `prompt'. Takes
* both newlines (if using dialog(1) versus Xdialog(1)) and escaped newlines
* into account. If no newlines (escaped or otherwise) appear in the buffer,
* `prompt' is returned. If passed a NULL pointer, returns NULL.
*/
char *
dialog_prompt_lastline(char *prompt, uint8_t nlstate)
{
char *lastline, *p;
uint8_t nls = nlstate; /* See dialog_prompt_nlstate() */
if (prompt == NULL) return NULL;
if (*prompt == '\0') return prompt; /* shortcut */
lastline = p = prompt;
while (*p != '\0')
{
/* dialog(1) and dialog(3) will render literal newlines */
if (use_dialog || use_libdialog) {
if (*p == '\n') {
if (use_libdialog || !nls) lastline = p + 1;
nls = 0; /* See declaration comment */
}
}
/* dialog(3) does not expand escaped newlines */
if (use_libdialog) {
p++;
continue;
}
if (*p == '\\' && *(p + 1) != '\0' && *(++p) == 'n') {
nls = 1; /* See declaration comment */
lastline = p + 1;
}
p++;
}
return lastline;
}
/*
* Returns the number of extra lines generated by wrapping the text in buffer
* pointed to by `prompt' within `ncols' columns (for prompts, this should be
* dwidth - 4). Also discounts dialog(1) color escape codes if enabled (via
* `use_color' global).
*/
int
dialog_prompt_wrappedlines(char *prompt, int ncols, uint8_t nlstate)
{
uint8_t backslash = 0;
uint8_t nls = nlstate; /* See dialog_prompt_nlstate() */
int wlines = 0, n = 0;
char *p = prompt;
/* `prompt' parameter is required */
if (p == NULL) return 0;
if (*p == '\0') return 0; /* shortcut */
/* Loop until the end of the string */
while (*p != '\0')
{
/* dialog(1) and dialog(3) will render literal newlines */
if (use_dialog || use_libdialog) {
if (*p == '\n') {
if (use_dialog || !nls) n = 0;
nls = 0; /* See declaration comment */
}
}
/* Check for backslash character */
if (*p == '\\') {
/* If second backslash, count as a single-char */
if ((backslash ^= 1) == 0) n++;
} else if (backslash) {
if (*p == 'n' && !use_libdialog) { /* new line */
/* NB: dialog(3) ignores escaped newlines */
nls = 1; /* See declaration comment */
n = 0;
} else if (use_color && *p == 'Z') {
if (*++p != '\0') p++;
backslash = 0;
continue;
} else /* [X]dialog(1)/dialog(3) only expand those */
n += 2;
backslash = 0;
} else
n++;
/* Did we pass the width barrier? */
if (n > ncols)
{
/*
* Work backward to find the first whitespace on-which
* dialog(1) will wrap the line (but don't go before
* the start of this line).
*/
char *cp = p;
while (n > 1 && !isspace(*cp)) {
cp--;
n--;
}
if (n > 0 && isspace(*cp)) p = cp;
wlines++;
n = 1;
}
p++;
}
return wlines;
}
/*
* Returns zero if the buffer pointed to by `prompt' contains an escaped
* newline but only if appearing after any/all literal newlines. This is
* specific to dialog(1) and does not apply to Xdialog(1).
*
* As an attempt to make shell scripts easier to read, dialog(1) will "eat"
* the first literal newline after an escaped newline. This however has a bug
* in its implementation in that rather than allowing `\\n\n' to be treated
* similar to `\\n' or `\n', dialog(1) expands the `\\n' and then translates
* the following literal newline (with or without characters between [!]) into
* a single space.
*
* If you want to be compatible with Xdialog(1), it is suggested that you not
* use literal newlines (they aren't supported); but if you have to use them,
* go right ahead. But be forewarned... if you set $DIALOG in your environment
* to something other than `cdialog' (our current dialog(1)), then it should
* do the same thing w/respect to how to handle a literal newline after an
* escaped newline (you could do no wrong by translating every literal newline
* into a space but only when you've previously encountered an escaped one;
* this is what dialog(1) is doing).
*
* The ``newline state'' (or nlstate for short; as I'm calling it) is helpful
* if you plan to combine multiple strings into a single prompt text. In lead-
* up to this procedure, a common task is to calculate and utilize the widths
* and heights of each piece of prompt text to later be combined. However, if
* (for example) the first string ends in a positive newline state (has an
* escaped newline without trailing literal), the first literal newline in the
* second string will be mangled.
*
* The return value of this function should be used as the `nlstate' argument
* to dialog_*() functions that require it to allow accurate calculations in
* the event such information is needed.
*/
uint8_t
dialog_prompt_nlstate(const char *prompt)
{
const char *cp;
if (prompt == NULL) return 0;
/*
* Work our way backward from the end of the string for efficiency.
*/
cp = prompt + strlen(prompt);
while (--cp >= prompt)
{
/*
* If we get to a literal newline first, this prompt ends in a
* clean state for rendering with dialog(1). Otherwise, if we
* get to an escaped newline first, this prompt ends in an un-
* clean state (following literal will be mangled; see above).
*/
if (*cp == '\n')
return 0;
else if (*cp == 'n' && --cp > prompt && *cp == '\\')
return 1;
}
return 0; /* no newlines (escaped or otherwise) */
}