/*
   Bacula(R) - The Network Backup Solution

   Copyright (C) 2000-2016 Kern Sibbald

   The original author of Bacula is Kern Sibbald, with contributions
   from many others, a complete list can be found in the file AUTHORS.

   You may use this file and others of this release according to the
   license defined in the LICENSE file, which includes the Affero General
   Public License, v3.0 ("AGPLv3") and some additional permissions and
   terms pursuant to its AGPLv3 Section 7.

   This notice must be preserved when any source code is 
   conveyed and/or propagated.

   Bacula(R) is a registered trademark of Kern Sibbald.
*/
/*
      Generalized console input/output handler
      A maintanable replacement for readline()

         Updated for Bacula, Kern Sibbald, December MMIII

      This code is in part derived from code that I wrote in
      1981, so some of it is a bit old and could use a cleanup.

*/

/*
 * UTF-8
 *  If the top bit of a UTF-8 string is 0 (8 bits), then it
 *    is a normal ASCII character.
 *  If the top two bits are 11 (i.e. (c & 0xC0) == 0xC0 then
 *    it is the start of a series of chars (up to 5)
 *  Each subsequent character starts with 10 (i.e. (c & 0xC0) == 0x80)
 */


#ifdef  TEST_PROGRAM
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <ctype.h>
#define HAVE_CONIO 1
#else

/* We are in Bacula */
#include "bacula.h"

#endif

#ifdef HAVE_CONIO

#include <curses.h>
#include <term.h>

#ifdef HAVE_SUN_OS
#ifndef _TERM_H
extern "C" int tgetent(void *, const char *);
extern "C" int tgetnum(const char *);
extern "C" char *tgetstr (const char*, char**);
# Note: the following on older (Solaris 10) systems
#  may need to be moved to after the #endif
extern "C" char *tgoto (const char *, int, int);
#endif
#elif defined(__sgi)
extern "C" int tgetent(char *, char *);
extern "C" int tgetnum(char id[2]);
extern "C" char *tgetstr(char id[2], char **);
extern "C" char *tgoto(char *, int, int);
#elif defined (__digital__) && defined (__unix__)
extern "C" int tgetent(void *, const char *);
extern "C" int tgetnum(const char *);
extern "C" char *tgetstr (const char*, char**);
extern "C" char *tgoto (const char *, int, int);
#endif
#include "func.h"


/* From termios library */
#if defined(HAVE_HPUX_OS) || defined(HAVE_AIX_OS)
static char *BC;
static char *UP;
#else
extern char *BC;
extern char *UP;
#endif

/* Forward referenced functions */
extern "C" {
static void sigintcatcher(int);
}

static void add_smap(char *str, int func);


/* Global variables */

static const char *t_up = "\n";                    /* scroll up character */
static const char *t_honk = "\007";                /* sound beep */
static char *t_il;                           /* insert line */
static char *t_dl;                           /* delete line */
static char *t_cs;                           /* clear screen */
static char *t_cl;                           /* clear line */
static int t_width = 79;                     /* terminal width */
static int t_height = 24;                    /* terminal height */
static int linsdel_ok = 0;              /* set if term has line insert & delete fncs */

static char *t_cm;                           /* cursor positioning */
static char *t_ti;                           /* init sequence */
static char *t_te;                           /* end sequence */
static char *t_do;                           /* down one line */
static char *t_sf;                           /* scroll screen one line up */

/* Keypad and Function Keys */
static char *kl;                             /* left key */
static char *kr;                             /* right */
static char *ku;                             /* up */
static char *kd;                             /* down */
static char *kh;                             /* home */
static char *kb;                             /* backspace */
static char *kD;                             /* delete key */
static char *kI;                             /* insert */
static char *kN;                             /* next page */
static char *kP;                             /* previous page */
static char *kH;                             /* home */
static char *kE;                             /* end */

#ifndef EOS
#define EOS  '\0'                     /* end of string terminator */
#endif

#define TRUE  1
#define FALSE 0
/*
 * Stab entry. Input chars (str), the length, and the desired
 *  func code.
 */
typedef struct s_stab {
   struct s_stab *next;
   char *str;
   int len;
   int func;
} stab_t;

#define MAX_STAB 30

static stab_t **stab = NULL;                 /* array of stabs by length */
static int num_stab;                         /* size of stab array */

static bool old_term_params_set = false;
static struct termios old_term_params;

/* Maintain lines in a doubly linked circular pool of lines. Each line is
   preceded by a header defined by the lstr structure */


struct lstr {                         /* line pool structure */
   struct lstr *prevl;                /* link to previous line */
   struct lstr *nextl;                /* link to next line */
   long len;                          /* length of line+header */
   char used;                         /* set if line valid */
   char line;                         /* line is actually varying length */
};

#ifdef unix
#define POOLEN 128000                 /* bytes in line pool */
#else
#define POOLEN 500                    /* bytes in line pool */
#endif
char pool[POOLEN];                    /* line pool */
#define PHDRL ((int)sizeof(struct lstr))  /* length of line header */

static struct lstr *lptr;             /* current line pointer */
static struct lstr *slptr;            /* store line pointer */
static int cl, cp;
static char *getnext(), *getprev();
static int first = 1;
static int mode_insert = 1;
static int mode_wspace = 1;           /* words separated by spaces */


static short char_map[600]= {
   0,                                  F_SOL,    /* ^a Line start */
   F_PRVWRD, /* ^b Previous word */    F_BREAK,  /* ^C break */
   F_DELCHR, /* ^D Delete character */ F_EOL,    /* ^e End of line */
   F_CSRRGT, /* ^f Right */            F_TABBAK, /* ^G Back tab */
   F_CSRLFT, /* ^H Left */             F_TAB,    /* ^I Tab */
   F_CSRDWN, /* ^J Down */             F_DELEOL, /* ^K kill to eol */
   F_CLRSCRN,/* ^L clear screen */     F_RETURN, /* ^M Carriage return */
   F_RETURN, /* ^N enter line  */      F_CONCAT, /* ^O Concatenate lines */
   F_CSRUP,  /* ^P cursor up */        F_TINS,   /* ^Q Insert character mode */
   F_PAGUP,  /* ^R Page up */          F_CENTER, /* ^S Center text */
   F_PAGDWN, /* ^T Page down */        F_DELSOL, /* ^U delete to start of line */
   F_DELWRD, /* ^V Delete word */      F_PRVWRD, /* ^W Previous word */
   F_NXTMCH, /* ^X Next match */       F_DELEOL, /* ^Y Delete to end of line */
   F_BACKGND,/* ^Z Background */       0x1B,     /* ^[=ESC escape */
   F_TENTRY, /* ^\ Entry mode */       F_PASTECB,/* ^]=paste clipboard */
   F_HOME,   /* ^^ Home */             F_ERSLIN, /* ^_ Erase line */

   ' ','!','"','#','$','%','&','\047',
   '(',')','*','+','\054','-','.','/',
   '0','1','2','3','4','5','6','7',
   '8','9',':',';','<','=','>','?',
   '@','A','B','C','D','E','F','G',
   'H','I','J','K','L','M','N','O',
   'P','Q','R','S','T','U','V','W',
   'X','Y','Z','[','\\',']','^','_',
   '\140','a','b','c','d','e','f','g',
   'h','i','j','k','l','m','n','o',
   'p','q','r','s','t','u','v','w',
   'x','y','z','{','|','}','\176',F_ERSCHR  /* erase character */

  };


/* Local variables */

#define CR '\r'                       /* carriage return */


/* Function Prototypes */

static unsigned int input_char(void);
static unsigned int t_gnc(void);
static void insert_space(char *curline, int line_len);
static void insert_hole(char *curline, int line_len);
static void forward(char *str, int str_len);
static void backup(char *curline);
static void delchr(int cnt, char *curline, int line_len);
static int iswordc(char c);
static int  next_word(char *ldb_buf);
static int  prev_word(char *ldb_buf);
static void prtcur(char *str);
static void poolinit(void);
static char * getnext(void);
static char * getprev(void);
static void putline(char *newl, int newlen);
static void t_honk_horn(void);
static void t_insert_line(void);
static void t_delete_line(void);
static void t_clrline(int pos, int width);
void t_sendl(const char *msg, int len);
void t_send(const char *msg);
void t_char(char c);
static void asclrs();
static void ascurs(int y, int x);

static void rawmode(FILE *input);
static void normode(void);
static unsigned t_getch();
static void asclrl(int pos, int width);
static void asinsl();
static void asdell();

int input_line(char *string, int length);
extern "C" {
void con_term();
}
void trapctlc();
int usrbrk();
void clrbrk();

void con_init(FILE *input)
{
   atexit(con_term);
   rawmode(input);
   trapctlc();
}

/*
 * Zed control keys
 */
void con_set_zed_keys(void)
{
   char_map[1]  = F_NXTWRD; /* ^A Next Word */
   char_map[2]  = F_SPLIT;  /* ^B Split line */
   char_map[3]  = F_EOI;    /* ^C Quit */
   char_map[4]  = F_DELCHR; /* ^D Delete character */
   char_map[5]  = F_EOF;    /* ^E End of file */
   char_map[6]  = F_INSCHR; /* ^F Insert character */
   char_map[7]  = F_TABBAK; /* ^G Back tab */
   char_map[8]  = F_CSRLFT; /* ^H Left */
   char_map[9]  = F_TAB;    /* ^I Tab */
   char_map[10] = F_CSRDWN; /* ^J Down */
   char_map[11] = F_CSRUP;  /* ^K Up */
   char_map[12] = F_CSRRGT; /* ^L Right */
   char_map[13] = F_RETURN; /* ^M Carriage return */
   char_map[14] = F_EOL;    /* ^N End of line */
   char_map[15] = F_CONCAT; /* ^O Concatenate lines */
   char_map[16] = F_MARK;   /* ^P Set marker */
   char_map[17] = F_TINS;   /* ^Q Insert character mode */
   char_map[18] = F_PAGUP;  /* ^R Page up */
   char_map[19] = F_CENTER; /* ^S Center text */
   char_map[20] = F_PAGDWN; /* ^T Page down */
   char_map[21] = F_SOL;    /* ^U Line start */
   char_map[22] = F_DELWRD; /* ^V Delete word */
   char_map[23] = F_PRVWRD; /* ^W Previous word */
   char_map[24] = F_NXTMCH; /* ^X Next match */
   char_map[25] = F_DELEOL; /* ^Y Delete to end of line */
   char_map[26] = F_DELLIN; /* ^Z Delete line */
   /* 27 = ESC */
   char_map[28] = F_TENTRY; /* ^\ Entry mode */
   char_map[29] = F_PASTECB;/* ^]=paste clipboard */
   char_map[30] = F_HOME;   /* ^^ Home */
   char_map[31] = F_ERSLIN; /* ^_ Erase line */

}

void con_term()
{
   normode();
}

#ifdef TEST_PROGRAM
/*
 * Guarantee that the string is properly terminated */
char *bstrncpy(char *dest, const char *src, int maxlen)
{
   strncpy(dest, src, maxlen-1);
   dest[maxlen-1] = 0;
   return dest;
}
#endif


/*
 * New style string mapping to function code
 */
static unsigned do_smap(unsigned c)
{
    char str[MAX_STAB];
    int len = 0;
    stab_t *tstab;
    int i, found;
    unsigned cm;

    len = 1;
    str[0] = c;
    str[1] = 0;

    cm = char_map[c];
    if (cm == 0) {
       return c;
    } else {
       c = cm;
    }
    for ( ;; ) {
       found = 0;
       for (i=len-1; i<MAX_STAB; i++) {
          for (tstab=stab[i]; tstab; tstab=tstab->next) {
             if (strncmp(str, tstab->str, len) == 0) {
                if (len == tstab->len) {
                   return tstab->func;
                }
                found = 1;
                break;                /* found possibility continue searching */
             }
          }
       }
       if (!found) {
          return len==1?c:0;
       }
       /* found partial match, so get next character and retry */
       str[len++] = t_gnc();
       str[len] = 0;
    }
}

#ifdef DEBUG_x
static void dump_stab()
{
    int i, j, c;
    stab_t *tstab;
    char buf[100];

    for (i=0; i<MAX_STAB; i++) {
       for (tstab=stab[i]; tstab; tstab=tstab->next) {
          for (j=0; j<tstab->len; j++) {
             c = tstab->str[j];
             if (c < 0x20 || c > 0x7F) {
                sprintf(buf, " 0x%x ", c);
                t_send(buf);
             } else {
                buf[0] = c;
                buf[1] = 0;
                t_sendl(buf, 1);
             }
          }
          sprintf(buf, " func=%d len=%d\n\r", tstab->func, tstab->len);
          t_send(buf);
       }
    }
}
#endif

/*
 * New routine. Add string to string->func mapping table.
 */
static void add_smap(char *str, int func)
{
   stab_t *tstab;
   int len;

   if (!str) {
      return;
   }
   len = strlen(str);
   if (len == 0) {
/*    errmsg("String for func %d is zero length\n", func); */
      return;
   }
   tstab = (stab_t *)malloc(sizeof(stab_t));
   memset(tstab, 0, sizeof(stab_t));
   tstab->len = len;
   tstab->str = (char *)malloc(tstab->len + 1);
   bstrncpy(tstab->str, str, tstab->len + 1);
   tstab->func = func;
   if (tstab->len > num_stab) {
      printf("stab string too long %d. Max is %d\n", tstab->len, num_stab);
      exit(1);
   }
   tstab->next = stab[tstab->len-1];
   stab[tstab->len-1] = tstab;
/* printf("Add_smap tstab=%x len=%d func=%d tstab->next=%x\n\r", tstab, len,
          func, tstab->next); */

}


/* Get the next character from the terminal - performs table lookup on
   the character to do the desired translation */
static unsigned int
input_char()
{
    unsigned c;

    if ((c=t_gnc()) <= 599) {         /* IBM generates codes up to 260 */
          c = do_smap(c);
    } else if (c > 1000) {            /* stuffed function */
       c -= 1000;                     /* convert back to function code */
    }
    if (c <= 0) {
        t_honk_horn();
    }
    /* if we got a screen size escape sequence, read height, width */
    if (c == F_SCRSIZ) {
       t_gnc();   /*  - 0x20 = y */
       t_gnc();   /*  - 0x20 = x */
       c = input_char();
    }
    return c;
}


/* Get a complete input line */

int
input_line(char *string, int length)
{
   char curline[2000];                /* edit buffer */
   int noline;
   unsigned c;
   int more;
   int i;

    if (first) {
       poolinit();                   /* build line pool */
       first = 0;
    }
    noline = 1;                       /* no line fetched yet */
    for (cl=cp=0; cl<length && cl<(int)sizeof(curline); ) {
       if (usrbrk()) {
          clrbrk();
          break;
       }
       switch (c=input_char()) {
       case F_RETURN:                /* CR */
           t_sendl("\r\n", 2);       /* yes, print it and */
           goto done;                /* get out */
       case F_CLRSCRN:               /* clear screen */
          asclrs();
          t_sendl(curline, cl);
          ascurs(0, cp);
          break;
       case F_CSRUP:
           if (noline) {             /* no line fetched yet */
               getnext();            /* getnext so getprev gets current */
               noline = 0;           /* we now have line */
           }
           bstrncpy(curline, getprev(), sizeof(curline));
           prtcur(curline);
           break;
       case F_CSRDWN:
           noline = 0;               /* mark line fetched */
           bstrncpy(curline, getnext(), sizeof(curline));
           prtcur(curline);
           break;
       case F_INSCHR:
           insert_space(curline, sizeof(curline));
           break;
       case F_DELCHR:
           delchr(1, curline, sizeof(curline));       /* delete one character */
           break;
       case F_CSRLFT:                /* Backspace */
           backup(curline);
           break;
       case F_CSRRGT:
           forward(curline, sizeof(curline));
           break;
       case F_ERSCHR:                /* Rubout */
           backup(curline);
           delchr(1, curline, sizeof(curline));
           if (cp == 0) {
              t_char(' ');
              t_char(0x8);
           }
           break;
       case F_DELEOL:
           t_clrline(0, t_width);
           if (cl > cp)
               cl = cp;
           break;
       case F_NXTWRD:
           i = next_word(curline);
           while (i--) {
              forward(curline, sizeof(curline));
           }
           break;
       case F_PRVWRD:
           i = prev_word(curline);
           while (i--) {
              backup(curline);
           }
           break;
       case F_DELWRD:
           delchr(next_word(curline), curline, sizeof(curline)); /* delete word */
           break;
       case F_NXTMCH:                /* Ctl-X */
           if (cl==0) {
               *string = EOS;        /* terminate string */
               return(c);            /* give it to him */
           }
           /* Note fall through */
       case F_DELLIN:
       case F_ERSLIN:
           while (cp > 0) {
              backup(curline);      /* backup to beginning of line */
           }
           t_clrline(0, t_width);     /* erase line */
           cp = 0;
           cl = 0;                   /* reset cursor counter */
           t_char(' ');
           t_char(0x8);
           break;
       case F_SOL:
           while (cp > 0) {
              backup(curline);
           }
           break;
       case F_EOL:
           while (cp < cl) {
               forward(curline, sizeof(curline));
           }
           while (cp > cl) {
               backup(curline);
           }
           break;
       case F_TINS:                  /* toggle insert mode */
           mode_insert = !mode_insert;  /* flip bit */
           break;
       default:
           if (c > 255) {            /* function key hit */
               if (cl==0) {          /* if first character then */
                  *string = EOS;     /* terminate string */
                  return c;          /* return it */
               }
               t_honk_horn();        /* complain */
           } else {
               if ((c & 0xC0) == 0xC0) {
                  if ((c & 0xFC) == 0xFC) {
                     more = 5;
                  } else if ((c & 0xF8) == 0xF8) {
                     more = 4;
                  } else if ((c & 0xF0) == 0xF0) {
                     more = 3;
                  } else if ((c & 0xE0) == 0xE0) {
                     more = 2;
                  } else {
                     more = 1;
                  }
               } else {
                  more = 0;
               }
               if (mode_insert) {
                  insert_space(curline, sizeof(curline));
               }
               curline[cp++] = c;    /* store character in line being built */
               t_char(c);      /* echo character to terminal */
               while (more--) {
                  c= input_char();
                  insert_hole(curline, sizeof(curline));
                  curline[cp++] = c;    /* store character in line being built */
                  t_char(c);      /* echo character to terminal */
               }
               if (cp > cl) {
                  cl = cp;           /* keep current length */
                  curline[cp] = 0;
               }
           }
           break;
       }                             /* end switch */
    }
/* If we fall through here rather than goto done, the line is too long
   simply return what we have now. */
done:
   curline[cl++] = EOS;              /* terminate */
   bstrncpy(string,curline,length);           /* return line to caller */
   /* Save non-blank lines. Note, put line zaps curline */
   if (curline[0] != EOS) {
      putline(curline,cl);            /* save line for posterity */
   }
   return 0;                         /* give it to him/her */
}

/* Insert a space at the current cursor position */
static void
insert_space(char *curline, int curline_len)
{
   int i;

   if (cp >= cl || cl+1 > curline_len) {
      return;
   }
   /* Note! source and destination overlap */
   memmove(&curline[cp+1],&curline[cp],i=cl-cp);
   cl++;
   curline[cp] = ' ';
   i = 0;
   while (cl > cp) {
      forward(curline, curline_len);
      i++;
   }
   while (i--) {
      backup(curline);
   }
}


static void
insert_hole(char *curline, int curline_len)
{
   int i;

   if (cp > cl || cl+1 > curline_len) {
      return;
   }
   /* Note! source and destination overlap */
   memmove(&curline[cp+1], &curline[cp], i=cl-cp);
   cl++;
   curline[cl] = 0;
}


/* Move cursor forward keeping characters under it */
static void
forward(char *str, int str_len)
{
   if (cp > str_len) {
      return;
   }
   if (cp >= cl) {
       t_char(' ');
       str[cp+1] = ' ';
       str[cp+2] = 0;
   } else {
       t_char(str[cp]);
       if ((str[cp] & 0xC0) == 0xC0) {
          cp++;
          while ((str[cp] & 0xC0) == 0x80) {
             t_char(str[cp]);
             cp++;
          }
          cp--;
       }
   }
   cp++;
}

/* How many characters under the cursor */
static int
char_count(int cptr, char *str)
{
   int cnt = 1;
   if (cptr > cl) {
      return 0;
   }
   if ((str[cptr] & 0xC0) == 0xC0) {
      cptr++;
      while ((str[cptr] & 0xC0) == 0x80) {
         cnt++;
         cptr++;
      }
   }
   return cnt;
}

/* Backup cursor keeping characters under it */
static void
backup(char *str)
{
    if (cp == 0) {
       return;
    }
    while ((str[cp] & 0xC0) == 0x80) {
       cp--;
    }
    t_char('\010');
    cp--;
}

/* Delete the character under the cursor */
static void
delchr(int del, char *curline, int line_len)
{
   int i, cnt;

   if (cp > cl || del == 0) {
      return;
   }
   while (del-- && cl > 0) {
      cnt = char_count(cp, curline);
      if ((i=cl-cp-cnt) > 0) {
         memcpy(&curline[cp], &curline[cp+cnt], i);
      }
      cl -= cnt;
      curline[cl] = EOS;
      t_clrline(0, t_width);
      i = 0;
      while (cl > cp) {
         forward(curline, line_len);
         i++;
      }
      while (i--) {
         backup(curline);
      }
   }
}

/* Determine if character is part of a word */
static int
iswordc(char c)
{
   if (mode_wspace)
      return !isspace(c);
   if (c >= '0' && c <= '9')
      return true;
   if (c == '$' || c == '%')
      return true;
   return isalpha(c);
}

/* Return number of characters to get to next word */
static int
next_word(char *ldb_buf)
{
   int ncp;

   if (cp > cl)
      return 0;
   ncp = cp;
   for ( ; ncp<cl && iswordc(*(ldb_buf+ncp)); ncp++) ;
   for ( ; ncp<cl && !iswordc(*(ldb_buf+ncp)); ncp++) ;
   return ncp-cp;
}

/* Return number of characters to get to previous word */
static int
prev_word(char *ldb_buf)
{
    int ncp, i;

    if (cp == 0)                      /* if at begin of line stop now */
        return 0;
    if (cp > cl)                      /* if past eol start at eol */
        ncp=cl+1;
    else
        ncp = cp;
    /* backup to end of previous word - i.e. skip special chars */
    for (i=ncp-1; i && !iswordc(*(ldb_buf+i)); i--) ;
    if (i == 0) {                     /* at beginning of line? */
        return cp;                    /* backup to beginning */
    }
    /* now move back through word to beginning of word */
    for ( ; i && iswordc(*(ldb_buf+i)); i--) ;
    ncp = i+1;                        /* position to first char of word */
    if (i==0 && iswordc(*ldb_buf))    /* check for beginning of line */
        ncp = 0;
    return cp-ncp;                    /* return count */
}

/* Display new current line */
static void
prtcur(char *str)
{
    while (cp > 0) {
       backup(str);
    }
    t_clrline(0,t_width);
    cp = cl = strlen(str);
    t_sendl(str, cl);
}


/* Initialize line pool. Split pool into two pieces. */
static void
poolinit()
{
   slptr = lptr = (struct lstr *)pool;
   lptr->nextl = lptr;
   lptr->prevl = lptr;
   lptr->used = 1;
   lptr->line = 0;
   lptr->len = POOLEN;
}


/* Return pointer to next line in the pool and advance current line pointer */
static char *
getnext()
{
   do {                              /* find next used line */
      lptr = lptr->nextl;
   } while (!lptr->used);
   return (char *)&lptr->line;
}

/* Return pointer to previous line in the pool */
static char *
getprev()
{
   do {                              /* find previous used line */
      lptr = lptr->prevl;
   } while (!lptr->used);
   return (char *)&lptr->line;
}

static void
putline(char *newl, int newlen)
{
   struct lstr *nptr;                /* points to next line */
   char *p;

   lptr = slptr;                     /* get ptr to last line stored */
   lptr = lptr->nextl;               /* advance pointer */
   if ((char *)lptr-pool+newlen+PHDRL > POOLEN) { /* not enough room */
       lptr->used = 0;               /* delete line */
       lptr = (struct lstr *)pool;   /* start at beginning of buffer */
   }
   while (lptr->len < newlen+PHDRL) { /* concatenate buffers */
       nptr = lptr->nextl;           /* point to next line */
       lptr->nextl = nptr->nextl;    /* unlink it from list */
       nptr->nextl->prevl = lptr;
       lptr->len += nptr->len;
   }
   if (lptr->len > newlen + 2 * PHDRL + 7) { /* split buffer */
       nptr = (struct lstr *)((char *)lptr + newlen + PHDRL);
       /* Appropriate byte alignment - for Intel 2 byte, but on
          Sparc we need 8 byte alignment, so we always do 8 */
       if (((long unsigned)nptr & 7) != 0) { /* test eight byte alignment */
           p = (char *)nptr;
           nptr = (struct lstr *)((((long unsigned) p) & ~7) + 8);
       }
       nptr->len = lptr->len - ((char *)nptr - (char *)lptr);
       lptr->len -= nptr->len;
       nptr->nextl = lptr->nextl;    /* link in new buffer */
       lptr->nextl->prevl = nptr;
       lptr->nextl = nptr;
       nptr->prevl = lptr;
       nptr->used = 0;
   }
   memcpy(&lptr->line,newl,newlen);
   lptr->used = 1;                   /* mark line used */
   slptr = lptr;                     /* save as stored line */
}

#ifdef  DEBUGOUT
static void
dump(struct lstr *ptr, char *msg)
{
    printf("%s buf=%x nextl=%x prevl=%x len=%d used=%d\n",
        msg,ptr,ptr->nextl,ptr->prevl,ptr->len,ptr->used);
    if (ptr->used)
        printf("line=%s\n",&ptr->line);
}
#endif  /* DEBUGOUT */


/* Honk horn on terminal */
static void
t_honk_horn()
{
   t_send(t_honk);
}

/* Insert line on terminal */
static void
t_insert_line()
{
   asinsl();
}

/* Delete line from terminal */
static void
t_delete_line()
{
   asdell();
}

/* clear line from pos to width */
static void
t_clrline(int pos, int width)
{
    asclrl(pos, width);           /* clear to end of line */
}

/* Helper function to add string preceded by
 *  ESC to smap table */
static void add_esc_smap(const char *str, int func)
{
   char buf[1000];
   buf[0] = 0x1B;                     /* esc */
   bstrncpy(buf+1, str, sizeof(buf)-1);
   add_smap(buf, func);
}

/* Set raw mode on terminal file.  Basically, get the terminal into a
   mode in which all characters can be read as they are entered.  CBREAK
   mode is not sufficient.
 */
static void rawmode(FILE *input)
{
   struct termios t;
   static char term_buf[2048];
   static char *term_buffer = term_buf;
   char *termtype = (char *)getenv("TERM");

   /* Make sure we are dealing with a terminal */
   if (!isatty(fileno(input))) {
      return;
   }
   if (tcgetattr(0, &old_term_params) != 0) {
      printf("conio: Cannot tcgetattr()\n");
      exit(1);
   }
   old_term_params_set = true;
   t = old_term_params;
   t.c_cc[VMIN] = 1; /* satisfy read after 1 char */
   t.c_cc[VTIME] = 0;
   t.c_iflag &= ~(BRKINT | IGNPAR | PARMRK | INPCK |
                  ISTRIP | ICRNL | IXON | IXOFF | INLCR | IGNCR);
   t.c_iflag |= IGNBRK;
   t.c_oflag |= ONLCR;
   t.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL | ICANON |
                  NOFLSH | TOSTOP);
   tcflush(0, TCIFLUSH);
   if (tcsetattr(0, TCSANOW, &t) == -1) {
      printf("Cannot tcsetattr()\n");
   }

   /* Defaults, the main program can override these */
   signal(SIGQUIT, SIG_IGN);
   signal(SIGHUP, SIG_IGN);
   signal(SIGINT, sigintcatcher);
   signal(SIGWINCH, SIG_IGN);

   if (!termtype) {
      printf("Cannot get terminal type.\n");
      normode();
      exit(1);
   }
   if (tgetent(term_buffer, termtype) < 0) {
      printf("Cannot get terminal termcap entry.\n");
      normode();
      exit(1);
   }
   t_width = t_height = -1;
   /* Note (char *)casting is due to really stupid compiler warnings */
   t_width = tgetnum((char *)"co") - 1;
   t_height = tgetnum((char *)"li");
   BC = NULL;
   UP = NULL;
   t_cm = (char *)tgetstr((char *)"cm", &term_buffer);
   t_cs = (char *)tgetstr((char *)"cl", &term_buffer); /* clear screen */
   t_cl = (char *)tgetstr((char *)"ce", &term_buffer); /* clear line */
   t_dl = (char *)tgetstr((char *)"dl", &term_buffer); /* delete line */
   t_il = (char *)tgetstr((char *)"al", &term_buffer); /* insert line */
   t_honk = (char *)tgetstr((char *)"bl", &term_buffer); /* beep */
   t_ti = (char *)tgetstr((char *)"ti", &term_buffer);
   t_te = (char *)tgetstr((char *)"te", &term_buffer);
   t_up = (char *)tgetstr((char *)"up", &term_buffer);
   t_do = (char *)tgetstr((char *)"do", &term_buffer);
   t_sf = (char *)tgetstr((char *)"sf", &term_buffer);

   num_stab = MAX_STAB;                  /* get default stab size */
   stab = (stab_t **)malloc(sizeof(stab_t *) * num_stab);
   memset(stab, 0, sizeof(stab_t *) * num_stab);

   /* Key bindings */
   kl = (char *)tgetstr((char *)"kl", &term_buffer);
   kr = (char *)tgetstr((char *)"kr", &term_buffer);
   ku = (char *)tgetstr((char *)"ku", &term_buffer);
   kd = (char *)tgetstr((char *)"kd", &term_buffer);
   kh = (char *)tgetstr((char *)"kh", &term_buffer);
   kb = (char *)tgetstr((char *)"kb", &term_buffer);
   kD = (char *)tgetstr((char *)"kD", &term_buffer);
   kI = (char *)tgetstr((char *)"kI", &term_buffer);
   kN = (char *)tgetstr((char *)"kN", &term_buffer);
   kP = (char *)tgetstr((char *)"kP", &term_buffer);
   kH = (char *)tgetstr((char *)"kH", &term_buffer);
   kE = (char *)tgetstr((char *)"kE", &term_buffer);

   add_smap(kl, F_CSRLFT);
   add_smap(kr, F_CSRRGT);
   add_smap(ku, F_CSRUP);
   add_smap(kd, F_CSRDWN);
   add_smap(kI, F_TINS);
   add_smap(kN, F_PAGDWN);
   add_smap(kP, F_PAGUP);
   add_smap(kH, F_HOME);
   add_smap(kE, F_EOF);


   add_esc_smap("[A",   F_CSRUP);
   add_esc_smap("[B",   F_CSRDWN);
   add_esc_smap("[C",   F_CSRRGT);
   add_esc_smap("[D",   F_CSRLFT);
   add_esc_smap("[1~",  F_HOME);
   add_esc_smap("[2~",  F_TINS);
   add_esc_smap("[3~",  F_DELCHR);
   add_esc_smap("[4~",  F_EOF);
   add_esc_smap("f",    F_NXTWRD);
   add_esc_smap("b",    F_PRVWRD);
}


/* Restore tty mode */
static void normode()
{
   if (old_term_params_set) {
      tcsetattr(0, TCSANOW, &old_term_params);
      old_term_params_set = false;
   }
}

/* Get next character from terminal/script file/unget buffer */
static unsigned
t_gnc()
{
    return t_getch();
}


/* Get next character from OS */
static unsigned t_getch(void)
{
   unsigned char c;

   if (read(0, &c, 1) != 1) {
      c = 0;
   }
   return (unsigned)c;
}

/* Send message to terminal - primitive routine */
void
t_sendl(const char *msg, int len)
{
   write(1, msg, len);
}

void
t_send(const char *msg)
{
   if (msg == NULL) {
      return;
   }
   t_sendl(msg, strlen(msg));    /* faster than one char at time */
}

/* Send single character to terminal - primitive routine - */
void
t_char(char c)
{
   (void)write(1, &c, 1);
}


static int brkflg = 0;              /* set on user break */

/* Routine to return true if user types break */
int usrbrk()
{
   return brkflg;
}

/* Clear break flag */
void clrbrk()
{
   brkflg = 0;

}

/* Interrupt caught here */
static void sigintcatcher(int sig)
{
   brkflg++;
   if (brkflg > 3) {
      normode();
      exit(1);
   }
   signal(SIGINT, sigintcatcher);
}


/* Trap Ctl-C */
void trapctlc()
{
   signal(SIGINT, sigintcatcher);
}


/* ASCLRL() -- Clear to end of line from current position */
static void asclrl(int pos, int width)
{
   int i;

   if (t_cl) {
       t_send(t_cl);                 /* use clear to eol function */
       return;
   }
   if (pos==1 && linsdel_ok) {
       t_delete_line();              /* delete line */
       t_insert_line();              /* reinsert it */
       return;
   }
   for (i=1; i<=width-pos+1; i++)
       t_char(' ');                  /* last resort, blank it out */
   for (i=1; i<=width-pos+1; i++)    /* backspace to original position */
       t_char(0x8);
   return;

}


/* ASCURS -- Set cursor position */
static void ascurs(int y, int x)
{
   t_send((char *)tgoto(t_cm, x, y));
}


/* ASCLRS -- Clear whole screen */
static void asclrs()
{
   ascurs(0,0);
   t_send(t_cs);
}



/* ASINSL -- insert new line after cursor */
static void asinsl()
{
   t_clrline(0, t_width);
   t_send(t_il);                      /* insert before */
}

/* ASDELL -- Delete line at cursor */
static void asdell()
{
   t_send(t_dl);
}

#endif
