openrc/src/libeinfo.c

/*
   einfo.c
   Gentoo informational functions
   Copyright 2007 Gentoo Foundation
   */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>

#include "einfo.h"
#include "rc.h"
#include "rc-misc.h"

/* Incase we cannot work out how many columns from ioctl, supply a default */
#define DEFAULT_COLS		 80

#define OK			"ok"
#define NOT_OK			"!!"

#define CHECK_VERBOSE		if (! is_env ("RC_VERBOSE", "yes")) return 0

/* Number of spaces for an indent */
#define INDENT_WIDTH		2

/* How wide can the indent go? */
#define INDENT_MAX		40

#define EBUFFER_LOCK		RC_SVCDIR "ebuffer/.lock"

/* A cheat sheet of colour capable terminals
   This is taken from DIR_COLORS from GNU coreutils
   We embed it here as we shouldn't depend on coreutils */
static const char *colour_terms[] = {
	"Eterm",
	"ansi",
	"color-xterm",
	"con132x25",
	"con132x30",
	"con132x43",
	"con132x60",
	"con80x25",
	"con80x28",
	"con80x30",
	"con80x43",
	"con80x50",
	"con80x60",
	"cons25",
	"console",
	"cygwin",
	"dtterm",
	"gnome",
	"konsole",
	"kterm",
	"linux",
	"linux-c",
	"mach-color",
	"mlterm",
	"putty",
	"rxvt",
	"rxvt-cygwin",
	"rxvt-cygwin-native",
	"rxvt-unicode",
	"screen",
	"screen-bce",
	"screen-w",
	"screen.linux",
	"vt100",
	"xterm",
	"xterm-256color",
	"xterm-color",
	"xterm-debian",
	NULL
};

static bool is_env (const char *var, const char *val)
{
	char *v;

	if (! var)
		return (false);

	v = getenv (var);
	if (! v)
		return (val ? false : true);

	return (strcasecmp (v, val) ? false : true);
}

bool colour_terminal (void)
{
	static int in_colour = -1;
	int i = 0;
	char *term;

	if (in_colour == 0)
		return (false);
	if (in_colour == 1)
		return (true);

	term = getenv ("TERM");
	/* If $TERM isn't set then the chances are we're in single user mode */
	if (! term)
		return (true);

	while (colour_terms[i]) {
		if (strcmp (colour_terms[i], term) == 0) {
			in_colour = 1;
			return (true);
		}
		i++;
	}

	in_colour = 0;
	return (false);
}

static int get_term_columns (void)
{
#ifdef TIOCGSIZE /* BSD */
	struct ttysize ts;

	if (ioctl(0, TIOCGSIZE, &ts) == 0)
		return (ts.ts_cols);
#elif TIOCGWINSZ /* Linux */
	struct winsize ws; 

	if (ioctl(0, TIOCGWINSZ, &ws) == 0)
		return (ws.ws_col);
#endif

	return (DEFAULT_COLS);
}

static int ebuffer (const char *cmd, int retval, const char *fmt, va_list ap)
{
	char *file = getenv ("RC_EBUFFER");
	FILE *fp;
	char buffer[RC_LINEBUFFER];
	int l = 1;

	if (! file || ! cmd || strlen (cmd) < 4)
		return (0);

	if (! (fp = fopen (file, "a"))) {
		fprintf (stderr, "fopen `%s': %s\n", file, strerror (errno));
		return (0);
	}

	fprintf (fp, "%s %d ", cmd, retval);

	if (fmt) {
		va_list apc;
		va_copy (apc, ap);
		l = vsnprintf (buffer, sizeof (buffer), fmt, apc);
		fprintf (fp, "%d %s\n", l, buffer);
		va_end (apc);
	} else
		fprintf (fp, "0\n");

	fclose (fp);
	return (l);
}

typedef struct func
{
	const char *name;
	int (*efunc) (const char *fmt, ...);
	int (*eefunc) (int retval, const char *fmt, ...);
	void (*eind) (void);
} func_t;

static const func_t funcmap[] = {
	{ "einfon", &einfon, NULL, NULL },
	{ "ewarnn", &ewarnn, NULL, NULL},
	{ "eerrorn", &eerrorn, NULL, NULL},
	{ "einfo", &einfo, NULL, NULL },
	{ "ewarn", &ewarn, NULL, NULL },
	{ "eerror", &eerror, NULL, NULL },
	{ "ebegin", &ebegin, NULL, NULL },
	{ "eend", NULL, &eend, NULL },
	{ "ewend", NULL, &ewend, NULL },
	{ "eindent", NULL, NULL, &eindent },
	{ "eoutdent", NULL, NULL, &eoutdent },
	{ "einfovn", &einfovn, NULL, NULL },
	{ "ewarnvn", &ewarnvn, NULL, NULL },
	{ "einfov", &einfov, NULL, NULL },
	{ "ewarnv", &ewarnv, NULL, NULL },
	{ "ebeginv", &ebeginv, NULL, NULL },
	{ "eendv", NULL, &eendv, NULL },
	{ "ewendv", NULL, &ewendv, NULL },
	{ "eindentv" ,NULL, NULL, &eindentv },
	{ "eoutdentv", NULL, NULL, &eoutdentv },
	{ NULL, NULL, NULL, NULL },
};

void eflush (void)
{
	FILE *fp;
	char *file = getenv ("RC_EBUFFER");
	char buffer[RC_LINEBUFFER];
	char *cmd;
	int retval = 0;
	int length = 0;
	char *token;
	char *p;
	struct stat buf;
	pid_t pid;
	char newfile[PATH_MAX];
	int i = 1;

	if (! file|| (stat (file, &buf) != 0)) {
		errno = 0;
		return;
	}

	/* Find a unique name for our file */
	while (true) {
		snprintf (newfile, sizeof (newfile), "%s.%d", file, i);
		if (stat (newfile, &buf) != 0) {
			if (rename (file, newfile))
				fprintf (stderr, "rename `%s' `%s': %s\n", file, newfile,
						 strerror (errno));
			break;
		}
		i++;
	}

	/* We fork a child process here so we don't hold anything up */
	if ((pid = fork ()) == -1) {
		fprintf (stderr, "fork: %s", strerror (errno));
		return;
	}

	if (pid != 0)
		return;

	/* Spin until we can lock the ebuffer */
	while (true) {
		struct timeval tv;
		tv.tv_sec = 0;
		tv.tv_usec = 20000;
		select (0, NULL, NULL, NULL, &tv);
		errno = 0;
		if (link (newfile, EBUFFER_LOCK) == 0)
			break;
		if (errno != EEXIST)
			fprintf (stderr, "link `%s' `%s': %s\n", newfile, EBUFFER_LOCK,
					 strerror (errno));
	}

	if (! (fp = fopen (newfile, "r"))) {
		fprintf (stderr, "fopen `%s': %s\n", newfile, strerror (errno));
		return;
	}

	unsetenv ("RC_EBUFFER");

	memset (buffer, 0, RC_LINEBUFFER);
	while (fgets (buffer, RC_LINEBUFFER, fp)) {
		i = strlen (buffer) - 1;
		if (i < 1)
			continue;

		if (buffer[i] == '\n')
			buffer[i] = 0;

		p = buffer;
		cmd = strsep (&p, " ");
		token = strsep (&p, " ");
		if (sscanf (token, "%d", &retval) != 1) {
			fprintf (stderr, "eflush `%s': not a number", token);
			continue;
		}
		token = strsep (&p, " ");
		if (sscanf (token, "%d", &length) != 1) {
			fprintf (stderr, "eflush `%s': not a number", token);
			continue;
		}

		i = 0;
		while (funcmap[i].name) {
			if (strcmp (funcmap[i].name, cmd) == 0) {
				if (funcmap[i].efunc) {
					if (p)
						funcmap[i].efunc ("%s", p);
					else
						funcmap[i].efunc (NULL, NULL);
				} else if (funcmap[i].eefunc) {
					if (p)
						funcmap[i].eefunc (retval, "%s", p);
					else
						funcmap[i].eefunc (retval, NULL, NULL);
				} else if (funcmap[i].eind)
					funcmap[i].eind ();
				else
					fprintf (stderr, "eflush `%s': no function defined\n", cmd);
				break;
			}
			i++;
		}

		if (! funcmap[i].name)
			fprintf (stderr, "eflush `%s': invalid function\n", cmd);
	}
	fclose (fp);

	if (unlink (EBUFFER_LOCK))
		fprintf (stderr, "unlink `%s': %s", EBUFFER_LOCK, strerror (errno));

	if (unlink (newfile))
		fprintf (stderr, "unlink `%s': %s", newfile, strerror (errno));

	_exit (EXIT_SUCCESS);
}

#define EBUFFER(_cmd, _retval, _fmt, _ap) { \
	int _i = ebuffer (_cmd, _retval, _fmt, _ap); \
	if (_i) \
	return (_i); \
}

static void elog (int level, const char *fmt, va_list ap)
{
	char *e = getenv ("RC_ELOG");
	va_list apc;

	if (fmt && e) {
		closelog ();
		openlog (e, LOG_PID, LOG_DAEMON);
		va_copy (apc, ap);
		vsyslog (level, fmt, apc);
		va_end (apc);
		closelog ();
	}
}

static int _eindent (FILE *stream)
{
	char *env = getenv ("RC_EINDENT");
	int amount = 0;
	char indent[INDENT_MAX];

	if (env) {
		errno = 0;
		amount = strtol (env, NULL, 0);
		if (errno != 0 || amount < 0)
			amount = 0;
		else if (amount > INDENT_MAX)
			amount = INDENT_MAX;

		if (amount > 0)
			memset (indent, ' ', amount);
	}

	/* Terminate it */
	memset (indent + amount, 0, 1);

	return (fprintf (stream, "%s", indent));
}

#define EINFOVN(_file, _colour) \
	if (colour_terminal ()) \
fprintf (_file, " " _colour "*" EINFO_NORMAL " "); \
else \
fprintf (_file, " * "); \
retval += _eindent (_file); \
{ \
	va_list _ap; \
	va_copy (_ap, ap); \
	retval += vfprintf (_file, fmt, _ap) + 3; \
	va_end (_ap); \
} \
if (colour_terminal ()) \
fprintf (_file, "\033[K");

static int _einfovn (const char *fmt, va_list ap)
{
	int retval = 0;

	EINFOVN (stdout, EINFO_GOOD);
	return (retval);
}

static int _ewarnvn (const char *fmt, va_list ap)
{
	int retval = 0;

	EINFOVN (stdout, EINFO_WARN);
	return (retval);
}

static int _eerrorvn (const char *fmt, va_list ap)
{
	int retval = 0;

	EINFOVN (stderr, EINFO_BAD);
	return (retval);
}

int einfon (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt || is_env ("RC_QUIET", "yes"))
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("einfon", 0, fmt, ap)))
		retval = _einfovn (fmt, ap);
	va_end (ap);

	return (retval);
}

int ewarnn (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt || is_env ("RC_QUIET", "yes"))
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("ewarnn", 0, fmt, ap)))
		retval = _ewarnvn (fmt, ap);
	va_end (ap);

	return (retval);
}

int eerrorn (const char *fmt, ...)
{
	int retval;
	va_list ap;

	va_start (ap, fmt);
	if (! (retval = ebuffer ("eerrorn", 0, fmt, ap)))
		retval = _eerrorvn (fmt, ap);
	va_end (ap);

	return (retval);
}

int einfo (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt || is_env ("RC_QUIET", "yes"))
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("einfo", 0, fmt, ap))) {
		retval = _einfovn (fmt, ap);
		retval += printf ("\n");
	}
	va_end (ap);

	return (retval);
}

int ewarn (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt || is_env ("RC_QUIET", "yes"))
		return (0);

	va_start (ap, fmt);
	elog (LOG_WARNING, fmt, ap);
	if (! (retval = ebuffer ("ewarn", 0, fmt, ap)))	{
		retval = _ewarnvn (fmt, ap);
		retval += printf ("\n");
	}
	va_end (ap);

	return (retval);
}

void ewarnx (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (fmt && ! is_env ("RC_QUIET", "yes")) {
		va_start (ap, fmt);
		elog (LOG_WARNING, fmt, ap);
		retval = _ewarnvn (fmt, ap);
		va_end (ap);
		retval += printf ("\n");
	}
	exit (EXIT_FAILURE);
}

int eerror (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	elog (LOG_ERR, fmt, ap);
	retval = _eerrorvn (fmt, ap);
	va_end (ap);
	retval += fprintf (stderr, "\n");

	return (retval);
}

void eerrorx (const char *fmt, ...)
{
	va_list ap;

	if (fmt) {
		va_start (ap, fmt);
		elog (LOG_ERR, fmt, ap);
		_eerrorvn (fmt, ap);
		va_end (ap);
		printf ("\n");
	}
	exit (EXIT_FAILURE);
}

int ebegin (const char *fmt, ...)
{
	int retval;
	va_list ap;

	if (! fmt || is_env ("RC_QUIET", "yes"))
		return (0);

	va_start (ap, fmt);
	if ((retval = ebuffer ("ebegin", 0, fmt, ap))) {
		va_end (ap);
		return (retval);
	}

	retval = _einfovn (fmt, ap);
	va_end (ap);
	retval += printf (" ...");
	if (colour_terminal ())
		retval += printf ("\n");

	return (retval);
}

static void _eend (int col, einfo_color_t color, const char *msg)
{
	FILE *fp = stdout;
	int i;
	int cols;

	if (! msg)
		return;

	if (color == einfo_bad)
		fp = stderr;

	cols = get_term_columns () - (strlen (msg) + 6);

	if (cols > 0 && colour_terminal ()) {
		fprintf (fp, "\033[A\033[%dC %s[ ", cols, EINFO_BRACKET);
		switch (color) {
			case einfo_good:
				fprintf (fp, EINFO_GOOD);
				break;
			case einfo_warn:
				fprintf (fp, EINFO_WARN);
				break;
			case einfo_bad:
				fprintf (fp, EINFO_BAD);
				break;
			case einfo_hilite:
				fprintf (fp, EINFO_HILITE);
				break;
			case einfo_bracket:
				fprintf (fp, EINFO_BRACKET);
				break;
			case einfo_normal:
				fprintf (fp, EINFO_NORMAL);
				break;
		}
		fprintf (fp, "%s%s ]%s\n", msg, EINFO_BRACKET, EINFO_NORMAL);
	} else {
		for (i = -1; i < cols - col; i++)
			fprintf (fp, " ");
		fprintf (fp, "[ %s ]\n", msg);
	}
}

static int _do_eend (const char *cmd, int retval, const char *fmt, va_list ap)
{
	int col = 0;
	FILE *fp;
	va_list apc;
	int eb;

	if (fmt) {
		va_copy (apc, ap);
		eb = ebuffer (cmd, retval, fmt, apc);
		va_end (apc);
		if (eb)
			return (retval);
	}

	if (fmt && retval != 0)	{
		va_copy (apc, ap);
		if (strcmp (cmd, "ewend") == 0) {
			col = _ewarnvn (fmt, apc);
			fp = stdout;
		} else {
			col = _eerrorvn (fmt, apc);
			fp = stderr;
		}
		va_end (apc);
		if (colour_terminal ())
			fprintf (fp, "\n");
	}

	_eend (col, retval == 0 ? einfo_good : einfo_bad, retval == 0 ? OK : NOT_OK);
	return (retval);
}

int eend (int retval, const char *fmt, ...)
{
	va_list ap;

	if (is_env ("RC_QUIET", "yes"))
		return (retval);

	va_start (ap, fmt);
	_do_eend ("eend", retval, fmt, ap);
	va_end (ap);

	return (retval);
}

int ewend (int retval, const char *fmt, ...)
{
	va_list ap;

	if (is_env ("RC_QUIET", "yes"))
		return (retval);

	va_start (ap, fmt);
	_do_eend ("ewend", retval, fmt, ap);
	va_end (ap);

	return (retval);
}

void ebracket (int col, einfo_color_t color, const char *msg)
{
	_eend (col, color, msg);
}

void eindent (void)
{
	char *env = getenv ("RC_EINDENT");
	int amount = 0;
	char num[10];

	if (ebuffer ("eindent", 0, NULL, NULL))
		return;

	if (env) {
		errno = 0;
		amount = strtol (env, NULL, 0);
		if (errno != 0)
			amount = 0;
	}

	amount += INDENT_WIDTH;
	if (amount > INDENT_MAX)
		amount = INDENT_MAX;

	snprintf (num, 10, "%08d", amount);
	setenv ("RC_EINDENT", num, 1);
}

void eoutdent (void)
{
	char *env = getenv ("RC_EINDENT");
	int amount = 0;
	char num[10];

	if (ebuffer ("eoutdent", 0, NULL, NULL))
		return;

	if (! env)
		return;

	errno = 0;
	amount = strtol (env, NULL, 0);
	if (errno != 0)
		amount = 0;
	else
		amount -= INDENT_WIDTH;

	if (amount <= 0)
		unsetenv ("RC_EINDENT");
	else {
		snprintf (num, 10, "%08d", amount);
		setenv ("RC_EINDENT", num, 1);
	}
}

int einfovn (const char *fmt, ...)
{
	int retval;
	va_list ap;

	CHECK_VERBOSE;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("einfovn", 0, fmt, ap)))
		retval = _einfovn (fmt, ap);
	va_end (ap);

	return (retval);
}

int ewarnvn (const char *fmt, ...)
{
	int retval;
	va_list ap;

	CHECK_VERBOSE;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("ewarnvn", 0, fmt, ap)))
		retval = _ewarnvn (fmt, ap);
	va_end (ap);

	return (retval);
}

int einfov (const char *fmt, ...)
{
	int retval;
	va_list ap;

	CHECK_VERBOSE;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("einfov", 0, fmt, ap))) {
		retval = _einfovn (fmt, ap);
		retval += printf ("\n");
	}
	va_end (ap);

	return (retval);
}

int ewarnv (const char *fmt, ...)
{
	int retval;
	va_list ap;

	CHECK_VERBOSE;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("ewarnv", 0, fmt, ap))) {
		retval = _ewarnvn (fmt, ap);
		retval += printf ("\n");
	}
	va_end (ap);
	retval += printf ("\n");

	return (retval);
}

int ebeginv (const char *fmt, ...)
{
	int retval;
	va_list ap;

	CHECK_VERBOSE;

	if (! fmt)
		return (0);

	va_start (ap, fmt);
	if (! (retval = ebuffer ("ebeginv", 0, fmt, ap))) {
		retval = _einfovn (fmt, ap);
		retval += printf (" ...");
		if (colour_terminal ())
			retval += printf ("\n");
	}
	va_end (ap);

	return (retval);
}

int eendv (int retval, const char *fmt, ...)
{
	va_list ap;

	CHECK_VERBOSE;

	va_start (ap, fmt);
	_do_eend ("eendv", retval, fmt, ap);
	va_end (ap);

	return (retval);
}

int ewendv (int retval, const char *fmt, ...)
{
	va_list ap;

	CHECK_VERBOSE;

	va_start (ap, fmt);
	_do_eend ("ewendv", retval, fmt, ap);
	va_end (ap);

	return (retval);
}

void eindentv (void)
{
	if (is_env ("RC_VERBOSE", "yes"))
		eindent ();
}

void eoutdentv (void)
{
	if (is_env ("RC_VERBOSE", "yes"))
		eoutdent ();
}