#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <stdio.h>

#define TRUE -1
#define FALSE 0
#define COPYBUFFSIZE 1024
#define FILENAMELEN 40
#define LINELEN 160

#ifdef DEBUG
#define TTYTYPE "/g/don/ttyset/ttytype"
#define TTYWHERE "/g/don/ttyset/ttywhere"
#define TTYS "/g/don/ttyset/ttys"
#define GETTYTAB "/g/don/ttyset/gettytab"
#else
#define TTYTYPE "/etc/ttytype"
#define TTYWHERE "/etc/ttywhere"
#define TTYS "/etc/ttys"
#define GETTYTAB "/etc/gettytab"
#endif

#define NEXTARGV ((argc-- > 0) ? *(++argv) : (char *)NULL)
#define SHORT_TTY_NAME (strcmp(tty_name,"console") ? tty_name + 3 : "co")

char *my_name,*tty_name = NULL,ability,speed,speed_name[LINELEN],ref[3],
     lnk[3],dev[3],who[14],where[41],what[LINELEN - 57],type[LINELEN],
     search_gettytab_by_name(),*search_gettytab_by_key(),*ttyname(),
     *index(),*rindex();


int errno;
FILE *gettytab;
struct file_of_lines {
    char file_name[LINELEN],temp_name[LINELEN];
    int changed;
    FILE *fp,*temp_fp;
    char line[LINELEN];
} ttytype = {TTYTYPE,"",FALSE,NULL,NULL,""},
  ttywhere = {TTYWHERE,"",FALSE,NULL,NULL,""},
  ttys = {TTYS,"",FALSE,NULL,NULL,""};

main(argc,argv)
int argc;
char **argv;
{
    my_name = *argv++; argc--;
     if((argc == 0) || (**argv == '-')) {
        if((tty_name = rindex(ttyname(0),'/')) < 0)
	    bomb("No tty\n");
	tty_name++;
        get_tty_info();
    }
    else {
        tty_name = *argv++; argc--;
        get_tty_info();
    }
    for(; argc-- != 0; argv++)
        if(**argv == '-')
            switch(argv[0][1]) {
            case 'e':
                ability = '1';
                ttys.changed = TRUE;
                break;
            case 'd':
                ability = '0';
                ttys.changed = TRUE;
                break;
            case 't':
                if(argv++, argc-- == 0)
                    bomb("You must give a terminal type after -t\n");
		if(index(*argv,' ') != NULL)
		    bomb("Spaces are not allowed in the terminal type \"%s\".\n",*argv);
                strcpy(type,*argv);
                ttytype.changed = TRUE; 
                break;
            case 's':
                if(argv++, argc-- == 0)
                    bomb("You must give a speed after -s\n");
                if((speed = search_gettytab_by_name(*argv)) == NULL)
                    bomb("%s is not a valid speed\n",*argv);
                ttys.changed = ttywhere.changed = TRUE;
                break;
            case 'w':
                if(argv[0][2] == 'h')
                    switch(argv[0][3]) {
                    case 'o':
                        if(argv++, argc-- == 0)
                            bomb("You must give a name after -who\n");
                        strncpy(who,*argv,14);
                        ttywhere.changed = TRUE;
                        break;
                    case 'e':
                        if(argv++, argc-- == 0)
                            bomb("You must give a location after -where\n");
                        strncpy(where,*argv,41);
                        ttywhere.changed = TRUE;
                        break;
                    case 'a':
                        if(argv++, argc-- == 0)
                            bomb("You must give a description after -what\n");
                        strncpy(what,*argv,LINELEN - 57);
                        ttywhere.changed = TRUE;
                        break;
                    case 'y':
                        bomb("Why not, ostrich breath?\n");
                        break;
                    default:
                        goto bad_switch;
                    }
                else goto bad_switch;
                break;
            default:
            bad_switch:
                bomb("Silly switch: %s\n",*argv);
                break;
            }
        else {
            put_tty_info();
            tty_name = *argv;
            get_tty_info();
        }
    put_tty_info();
}

get_tty_info()
{
    char *word_end;
    int starts_in_third_column(),ends_with(),starts_with();

    search_file(&ttys,starts_in_third_column,tty_name);
    ability = ttys.line[0];
    speed = ttys.line[1];
    *speed_name = '\0';
    search_file(&ttytype,ends_with,tty_name);
    if((word_end = index(ttytype.line,' ')) == NULL)
        bomb("Bad format in %s\n",ttytype.file_name);
    *word_end = '\0';
    strcpy(type,ttytype.line);
    search_file(&ttywhere,starts_with,SHORT_TTY_NAME);
    ttywhere.line[strlen(ttywhere.line) - 1] = '\0';
    get_field(ref,ttywhere.line+4,3);
    get_field(lnk,ttywhere.line+8,3);
    get_field(dev,ttywhere.line+12,3);
    get_field(who,ttywhere.line+26,14);
    get_field(where,ttywhere.line+41,15);
    get_field(what,ttywhere.line+57,22);
}

put_tty_info()
{
    list_tty_info();
    if(ttys.changed == TRUE) {
        ttys.line[0] = ability;
        ttys.line[1] = speed;
        write_back(&ttys);
    }
    else
        clean_up(&ttys);
    if(ttytype.changed == TRUE) {
        sprintf(ttytype.line,"%s %s\n",type,tty_name);
        write_back(&ttytype);
    }
    else
        clean_up(&ttytype);
    if(ttywhere.changed == TRUE) {
        sprintf(ttywhere.line,
                "%-3.3s %3.3s %-3.3s %-3.3s %-9.9s %-14.14s %-15.15s %.22s\n",
                SHORT_TTY_NAME,ref,lnk,dev,speed_name,who,where,what);
        write_back(&ttywhere);
    }
    else
        clean_up(&ttywhere);
}
    
list_tty_info()
{
    if(*speed_name == '\0')
        search_gettytab_by_key(speed);
    printf("%s: %sabled, speed \"%s\", type \"%s\",\n",
	   tty_name,ability == '1' ? "en" : "dis",speed_name,type);
    printf("who \"%s\", where \"%s\", what \"%s\".\n",
           who,where,what);
}

FILE *open_file(file_name,mode)
char *file_name,*mode;
{
    FILE *fp;

    if((fp = fopen(file_name,mode)) == NULL)
        bomb("Error opening %s\n",file_name);
    return(fp);
}

starts_with(line,string)
char *line,*string;
{
    return(!strncmp(line,string,strlen(string)));
}

ends_with(line,string)
char *line,*string;
{
    return(!strncmp(line + strlen(line) - strlen(string) - 1,
		    string,strlen(string)));
}

starts_in_third_column(line,string)
char *line,*string;
{
    return(!strncmp(line+2,string,strlen(string)));
}

search_file(this_file,compare,string)
struct file_of_lines *this_file;
int (*compare)();
char *string;
{
    struct stat st;
    int temp_fd;

    this_file->changed = FALSE;
    this_file->fp = open_file(this_file->file_name,"r");
    if(fstat(fileno(this_file->fp),&st) < 0)
        bomb("Error doing fstat to %s\n",this_file->file_name);
    sprintf(this_file->temp_name,"%s.%d",this_file->file_name,getpid());
    temp_fd = open(this_file->temp_name,O_CREAT|O_RDWR|O_TRUNC,st.st_mode);
    if(temp_fd < 0)
        bomb("Error opening %s\n",this_file->temp_name);
    if(fchown(temp_fd,st.st_uid,st.st_gid) < 0)
        bomb("Error doing chown on %s\n",this_file->temp_name);
    if((this_file->temp_fp = fdopen(temp_fd,"w")) < 0)
        bomb("Error doing fdopen on %s\n",this_file->temp_name);
    while((fgets(this_file->line,LINELEN,this_file->fp ) != NULL) &&
          !(*compare)(this_file->line,string))
        if(fputs(this_file->line,this_file->temp_fp) == EOF)
	    bomb("Error doing fputs to %s\n",this_file->temp_name);
    if(feof(this_file->fp))
        bomb("Can't find %s in %s\n",string,this_file->file_name);
    strncpy(this_file->line + strlen(this_file->line),"",
	    LINELEN - strlen(this_file->line));
}

write_back(this_file)
struct file_of_lines *this_file;
{
    char copy_buff[COPYBUFFSIZE];
    int transfered;

    if(fwrite(this_file->line,1,strlen(this_file->line),
	      this_file->temp_fp) != strlen(this_file->line))
	bomb("Error writing line to %s\n",this_file->temp_name);
    while((transfered = fread(copy_buff,1,COPYBUFFSIZE,this_file->fp)) > 0)
        if(fwrite(copy_buff,1,transfered,this_file->temp_fp) != transfered)
            bomb("Error writing to %s\n",this_file->temp_name);
    if(fclose(this_file->temp_fp))
        bomb("Error closing %s\n",this_file->temp_name);
    if(rename(this_file->temp_name,this_file->file_name) < 0)
        bomb("Error renaming %s to %s\n",this_file->temp_name,
                                         this_file->file_name);
}

clean_up(this_file)
struct file_of_lines *this_file;
{
    if(this_file->temp_fp != NULL)
        fclose(this_file->temp_fp);
    if(*this_file->temp_name != '\0')
        unlink(this_file->temp_name);
}

sub_string(line,string)
char *line,*string;
{
    int string_len = strlen(string),
        line_len = strlen(line);

    while(line_len-- >= string_len)
        if(!strncmp(line++,string,string_len))
            return(TRUE);
    return(FALSE);
}

bomb(msg,a1,a2)
char *msg,*a1,*a2;
{
    fprintf(stderr,"%s: errno=%d: ",my_name,errno);
    fprintf(stderr,msg,a1,a2);
    clean_up(&ttytype);
    clean_up(&ttywhere);
    clean_up(&ttys);
    exit(-1);
}

char search_gettytab_by_name(name)
char *name; 
{
    char line[LINELEN],*lp,*pp,*strcat();
    FILE *this_file;

    this_file = open_file(GETTYTAB,"r");
    while(fgets(line,LINELEN,this_file) != NULL) {
	if(line[strlen(line)-1] == '\n')
	    line[strlen(line)-1] = '\0';
        if((*line != '\0') && (*line != '#')) {
	    lp = line;
            while((*lp != '\0') && (*lp != ':')) {
	        pp = name;
                while((*lp != '\0') && (*lp != '|') && (*lp != ':') &&
		      (*pp != '\0') && (*pp == *lp))
		    pp++, lp++;
                if((*pp == '\0') && ((*lp == '|') || (*lp == ':')))
                    return(*line);
		while((*lp != '|') && (*lp != ':'))
		    lp++;
                lp++;
            }
            while((line[strlen(line)-1] == '\\')  &&
                  (fgets(line,LINELEN,this_file) != NULL))
	        if(line[strlen(line)-1] == '\n')
		    line[strlen(line)-1] = '\0'; 
	}
    }
    bomb("Can't find speed %s in %s\n",name,GETTYTAB);
}

char *search_gettytab_by_key(key)
char key;
{
    char line[LINELEN],*lb,*lp,*strip();
    FILE *gettytab;

    gettytab = open_file(GETTYTAB,"r");
    while(fgets(line,LINELEN,gettytab) != NULL)
        if(line[0] != '#')
            if((line[0] == key) && (line[1] == '|')) {
                lp = line;
                lb = line + 2;
                while((*lp != '\0') && (*lp != ':'))
                    if(*(lp++) == '|')
                        lb = lp;
                if(*lp == '\0')
                    bomb("Bad format in %s\n",GETTYTAB);
                *lp = '\0';
                strcpy(speed_name,lb);
                return(speed_name);
            }
    bomb("Can't find speed %c in %s\n",key,GETTYTAB);
}

get_field(into,from,len)
char *into,*from;
int len;
{
    char *string_end;

    from[len] = '\0';
    for(string_end = from; *string_end != '\0'; string_end++);
    while((from < string_end) && (*from == ' '))
        from++;
    while((string_end > from) && (*(string_end - 1) == ' '))
        string_end--;
    *string_end = '\0';
    return(strncpy(into,from,len));
}