/*
**  SETPROCTITLE -- set process title for ps
**
**	Parameters:
**		fmt -- a printf style format string.
**		a, b, c -- possible parameters to fmt.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Clobbers argv of our main procedure so ps(1) will
**		display the title.
*/

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <termios.h>

#include "../config.h"

#ifdef HAVE_GRP_H
#include <grp.h>
#endif

#ifdef HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif

#ifdef HAVE_STDARG_H
#include <stdarg.h>
#else
#ifdef HAVE_VARARGS_H
#include <varargs.h>
#endif
#endif

#ifdef __STDC__
#ifndef __P
#define __P(x)  x
#endif
#else
#ifndef __P
#define __P(x)  ()
#endif
#endif /* __STDC__ */


#define SPT_NONE	0	/* don't use it at all */
#define SPT_REUSEARGV	1	/* cover argv with title information */
#define SPT_BUILTIN	2	/* use libc builtin */
#define SPT_PSTAT	3	/* use pstat(PSTAT_SETCMD, ...) */
#define SPT_PSSTRINGS	4	/* use PS_STRINGS->... */
#define SPT_CHANGEARGV	7	/* write our own strings into argv[] */

#define SPACELEFT(buf, ptr)       (sizeof buf - ((ptr) - buf))

#ifdef __FreeBSD__
# define SPT_TYPE	SPT_BUILTIN
#endif

#ifdef __Linux__
# define SPT_TYPE	SPT_REUSEARGV
#endif

#ifndef SPT_TYPE
# define SPT_TYPE	SPT_REUSEARGV
#endif /* ! SPT_TYPE */

#define MAXLINE		2048

#if SPT_TYPE != SPT_NONE && SPT_TYPE != SPT_BUILTIN

# if SPT_TYPE == SPT_PSTAT
#  include <sys/pstat.h>
# endif /* SPT_TYPE == SPT_PSTAT */
# if SPT_TYPE == SPT_PSSTRINGS
#  include <machine/vmparam.h>
#  include <sys/exec.h>
#  ifndef PS_STRINGS	/* hmmmm....  apparently not available after all */
#   undef SPT_TYPE
#   define SPT_TYPE	SPT_REUSEARGV
#  else /* ! PS_STRINGS */
#   ifndef NKPDE			/* FreeBSD 2.0 */
#    define NKPDE 63
typedef unsigned int	*pt_entry_t;
#   endif /* ! NKPDE */
#  endif /* ! PS_STRINGS */
# endif /* SPT_TYPE == SPT_PSSTRINGS */

# if SPT_TYPE == SPT_PSSTRINGS || SPT_TYPE == SPT_CHANGEARGV
#  define SETPROC_STATIC	static
# else /* SPT_TYPE == SPT_PSSTRINGS || SPT_TYPE == SPT_CHANGEARGV */
#  define SETPROC_STATIC
# endif /* SPT_TYPE == SPT_PSSTRINGS || SPT_TYPE == SPT_CHANGEARGV */

# ifndef SPT_PADCHAR
#  define SPT_PADCHAR	' '
# endif /* ! SPT_PADCHAR */

#endif /* SPT_TYPE != SPT_NONE && SPT_TYPE != SPT_BUILTIN */

#ifndef SPT_BUFSIZE
# define SPT_BUFSIZE	MAXLINE
#endif /* ! SPT_BUFSIZE */

#if _FFR_SPT_ALIGN

/*
**  It looks like the Compaq Tru64 5.1A now aligns argv and envp to
**  64 bit alignment, so unless each piece of argv and envp is a multiple
**  of 8 bytes (including terminating NULL), initsetproctitle() won't use
**  any of the space beyond argv[0].  Be sure to set SPT_ALIGN_SIZE if
**  you use this FFR.
*/

# ifdef SPT_ALIGN_SIZE
#  define SPT_ALIGN(x, align)	(((((x) + SPT_ALIGN_SIZE) >> (align)) << (align)) - 1)
# else /* SPT_ALIGN_SIZE */
#  define SPT_ALIGN(x, align)	(x)
# endif /* SPT_ALIGN_SIZE */
#else /* _FFR_SPT_ALIGN */
# define SPT_ALIGN(x, align)	(x)
#endif /* _FFR_SPT_ALIGN */

/*
**  Pointers for setproctitle.
**	This allows "ps" listings to give more useful information.
*/

static char	**Argv = NULL;		/* pointer to argument vector */
static char	*LastArgv = NULL;	/* end of argv */
#if SPT_TYPE != SPT_BUILTIN
void	setproctitle (const char *, ...);
#endif /* SPT_TYPE != SPT_BUILTIN */

void
initsetproctitle(argc, argv, envp)
	int argc;
	char **argv;
	char **envp;
{
	register int i;
	int align;
	extern char **environ;

	/*
	**  Move the environment so setproctitle can use the space at
	**  the top of memory.
	*/

	if (envp != NULL)
	{
		for (i = 0; envp[i] != NULL; i++)
			continue;
		environ = (char **) malloc(sizeof (char *) * (i + 1));
		for (i = 0; envp[i] != NULL; i++)
			environ[i] = strdup(envp[i]);
		environ[i] = NULL;
	}

	/*
	**  Save start and extent of argv for setproctitle.
	*/

	Argv = argv;

	/*
	**  Determine how much space we can use for setproctitle.
	**  Use all contiguous argv and envp pointers starting at argv[0]
	*/

	align = -1;
#if _FFR_SPT_ALIGN
# ifdef SPT_ALIGN_SIZE
	for (i = SPT_ALIGN_SIZE; i > 0; i >>= 1)
		align++;
# endif /* SPT_ALIGN_SIZE */
#endif /* _FFR_SPT_ALIGN */

	for (i = 0; i < argc; i++)
	{
		if (i == 0 || LastArgv + 1 == argv[i])
			LastArgv = argv[i] + SPT_ALIGN(strlen(argv[i]), align);
	}
	for (i = 0; LastArgv != NULL && envp != NULL && envp[i] != NULL; i++)
	{
		if (LastArgv + 1 == envp[i])
			LastArgv = envp[i] + SPT_ALIGN(strlen(envp[i]), align);
	}
}

#if SPT_TYPE != SPT_BUILTIN

void setproctitle(const char *fmt, ...)
{
# if SPT_TYPE != SPT_NONE
	register int i;
	register char *p;
	static char buf[SPT_BUFSIZE];
        va_list ap;

#  if SPT_TYPE == SPT_PSTAT
	union pstun pst;
#  endif /* SPT_TYPE == SPT_PSTAT */

	p = buf;

	/* print sendmail: heading for grep */
	(void) strncpy(p, "pppserver: ", SPACELEFT(buf, p));
	p += strlen(p);

	/* print the argument string */
	va_start(ap, fmt);
	(void) vsnprintf(p, SPACELEFT(buf, p), fmt, ap);
	va_end(ap);

	i = (int) strlen(buf);
	if (i < 0)
		return;

#  if SPT_TYPE == SPT_PSTAT
	pst.pst_command = buf;
	pstat(PSTAT_SETCMD, pst, i, 0, 0);
#  endif /* SPT_TYPE == SPT_PSTAT */

#  if SPT_TYPE == SPT_PSSTRINGS
	PS_STRINGS->ps_nargvstr = 1;
	PS_STRINGS->ps_argvstr = buf;
#  endif /* SPT_TYPE == SPT_PSSTRINGS */

#  if SPT_TYPE == SPT_REUSEARGV
	if (LastArgv == NULL)
		return;

	if (i > LastArgv - Argv[0] - 2)
	{
		i = LastArgv - Argv[0] - 2;
		buf[i] = '\0';
	}
        memset (Argv[0], '\0', LastArgv - Argv[0] - 2);
	(void) strncpy(Argv[0], buf, i);
	Argv[1] = NULL;
#  endif /* SPT_TYPE == SPT_REUSEARGV */
#  if SPT_TYPE == SPT_CHANGEARGV
	Argv[0] = buf;
	Argv[1] = 0;
#  endif /* SPT_TYPE == SPT_CHANGEARGV */
# endif /* SPT_TYPE != SPT_NONE */
}

#endif /* SPT_TYPE != SPT_BUILTIN */

#ifndef HAVE_OPENPTY

#define TTY_LETTERS "pqrstuvwxyzPQRST"

int
openpty(amaster, aslave, name, termp, winp)
	int *amaster, *aslave;
	char *name;
	struct termios *termp;
	struct winsize *winp;
{
	char line[] = "/dev/ptyXX";
	register const char *cp1, *cp2;
	register int master, slave, ttygid;
	struct group *gr;

	if ((gr = getgrnam("tty")) != NULL)
		ttygid = gr->gr_gid;
	else
		ttygid = -1;

	for (cp1 = TTY_LETTERS; *cp1; cp1++) {
		line[8] = *cp1;
		for (cp2 = "0123456789abcdef"; *cp2; cp2++) {
			line[9] = *cp2;
			line[5] = 'p';
			if ((master = open(line, O_RDWR, 0)) == -1) {
				if (errno == ENOENT)
					return (-1);	/* out of ptys */
			} else {
				line[5] = 't';
				(void) chown(line, getuid(), ttygid);
				(void) chmod(line, S_IRUSR|S_IWUSR|S_IWGRP);
/* which is BSD only		(void) revoke(line); */
				if ((slave = open(line, O_RDWR, 0)) != -1) {
					*amaster = master;
					*aslave = slave;
					if (name)
						strcpy(name, line);
					if (termp)
						(void) tcsetattr(slave, 
							TCSAFLUSH, termp);
					if (winp)
						(void) ioctl(slave, TIOCSWINSZ, 
							(char *)winp);
					return (0);
				}
				(void) close(master);
			}
		}
	}
	errno = ENOENT;	/* out of ptys */
	return (-1);
}

#endif