jchvr@ihlpg.UUCP (VanRietschote) (01/07/86)
---
The program answer will auto answer your unix mail while you are away.
The best place to run this program from is via crontab(1) of course.
See next mail for manual page on all its capabilities.
Anyone is free to use or abuse this program at their own risk.
#------- cut here -------
/* answer.c -*-update-version-*-
** program to auto answer unix mail with absence notice
** HFVR VERSION=Thu Jan 2 09:13:41 1986
*/
#include <stdio.h>
#include <sys/types.h>
#include <signal.h>
#include <ctype.h>
#include <time.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#define equal !strcmp
#define equaln !strncmp
#define TRUE 1
#define FALSE 0
#define TOSIZE 512 /* size of buffer to hold dests */
#define MAXLINES 50 /* max nr of from lines */
#define LINELENGTH 256 /* max length from line */
char ANSWER[] = "Subject: Answering Service";
char TEMPA[] = "/usr/tmp/AXXXXX"; /* answer file */
char TEMPM[] = "/usr/tmp/MXXXXX"; /* copy of $MAIL file */
char subject[LINELENGTH]; /* msg subject line */
char NAME[] = "answer";
char VERSION[] = "Version 0.999";
char rmtfrom[] = " remote from ";
char fwrdmsg[] = " forwarded by ";
char from[] = "From ";
char because[80] ; /* reason for not sending reply */
FILE *f1; /* input file */
char *lp; /* pointer for reading file */
char line[LINELENGTH]; /* line last read from f1 */
FILE *f2; /* anwer file */
int frcnt; /* nr of from lines in message */
char frlist[MAXLINES][LINELENGTH]; /* from lines in message */
int DEBUG = FALSE;
/* TIME: return pointer to \0 terminated string with YYMMDD hh:mm:ss in it */
char *TIME()
{ extern long time();
extern struct tm *localtime();
struct tm *local;
long seconds;
static char times[15];
seconds = time(0);
local = localtime(&seconds);
sprintf(times,"%.2d%.2d%.2d %.2d:%.2d:%.2d",local->tm_year
,local->tm_mon + 1
,local->tm_mday
,local->tm_hour
,local->tm_min
,local->tm_sec);
return(times);
}/*TIME*/
#define ERRTEMPA 1
#define ERRTEMPM 2
#define ERRNODIR 3
/* print error messages on sterr and exit*/
error(nr)
int nr;
{
fprintf(stderr,"%s ERROR : ",TIME());
switch (nr) {
case ERRTEMPA : fprintf(stderr,"Cannot create answer TEMP file");
break;
case ERRTEMPM : fprintf(stderr,"Cannot create copy of mail in TEMPM");
break;
case ERRNODIR : fprintf(stderr,"$HOME/mail directory must be drwx------");
break;
default: fprintf(stderr,"Something is wrong");
break;
}
fprintf(stderr,"\n");
exit(1);
}/*error*/
/*
* sindex looks for an occurance of the string s2 in the string
* s1. If s2 does not ocurr, sindex returns -1. Otherwise, sindex
* returns the integer offset from s1 where s2 ocurrs.
*/
int sindex(s1,s2)
char *s1;
char *s2;
{
register char *p1;
register char *p2;
register int flag;
int ii;
p1 = &s1[0];
p2 = &s2[0];
flag = -1;
for(ii = 0; ; ii++) {
while(*p1 == *p2) {
if(flag < 0) flag = ii;
if(*p1++ == 0) return(flag);
p2++;
}
if(*p2 == 0) return(flag);
if(flag >= 0) {
flag = -1;
p2 = &s2[0];
}
if(*s1++ == 0) return(flag);
p1 = s1;
}
}/*sindex*/
/* returns pointer to string with sender address in it
** input is frlist[] with lines like:
**
** [>]From USER DATE or
** [>]From USER DATE forwarded by WHOCARES or
** [>]From USER DATE remote from MACHINE
**
** some lines might be duplicated
** we save only the last USER and string together all MACHINEs
** except if the previous machine equals the current one
** forwarded by lines are simply ignored
** address format is mach!mach!....!user or user
** if flg TRUE then it is also printed to stdout
*/
char *frflsh(flg)
{
static char address[TOSIZE] ;
char user[80];
char mach1[80] ; /* previous machine name */
char mach2[80] ; /* current machine name */
register int i;
int j;
register char *p;
register char *q;
strcpy(address,"");
strcpy(mach1,"");
for (i = 0 ; i < frcnt ; i++) { /* examine every From line */
p = frlist[i] ;
if ( *p == '>' ) p++; /* skip leading > */
if ( equaln(p, from , 5 ) ) {
p += 5; /* skip FromSP */
} else {
continue; /* does not match FromSP , try next line */
}
/* get user from line and skip past it */
/* but first skip past spaces and tabs */
while ( *p == ' ' || *p == '\t' ) p++;
q = user;
while ( *p != 10 && *p != '\0' && *p != ' ' && *p != '\t' ) {
*q = *p;
p++; q++;
}
*q = '\0';
/* get machine name */
strcpy(mach1,mach2); /* save previous name */
/* see if 'remote from' in line */
j = sindex(frlist[i], rmtfrom) ;
if ( j == -1 ) continue ; /* no so try next line */
p = &frlist[i][j+sizeof(rmtfrom) -1]; /* skip past remote from */
while ( *p == ' ' || *p == '\t' ) p++; /* skip spaces */
q = mach2;
while ( *p != 10 && *p != '\0' && *p != ' ' && *p != '\t' ) {
*q = *p;
p++; q++;
}
*q = '\0';
/* append to address if different from previous machine mach1 */
if ( equal(mach1,mach2) ) {
continue; /* equal so skip it */
} else {
strcat(address,mach2);
strcat(address,"!");
}
}/* for */
strcat(address,user);
if (flg) printf("Sender=%s\n",address);
return(address);
}/*frflsh*/
/*
* Determine if line is genuine article.
* Should be of 2 forms:
* From.*[0-9][0-9]:[0-9][0-9].*
* or
* >From.*[0-9][0-9]:[0-9][0-9].*
*
* The [0-9] stuff is the date representation by ctime.
* Some systems use only the 09:43 part of the time (i.e.
* no seconds representation).
*/
Isfrom(line)
register char *line; /* line to parse */
{
register char *p;
extern char *strchr();
if(equaln(line, from, 5))
{
if((p=strchr(line, ':')) != NULL)
{
colontest:
if( isdigit(p[-2]) &&
isdigit(p[-1]) &&
isdigit(p[1]) &&
isdigit(p[2])) return(1);
}
/*
* If more colons, try again.
*/
if(p=strchr(++p, ':'))
goto colontest;
}
return(0);
}/*Isfrom*/
/*fillfrom: fills frlist[] with FROM lines and sets frcnt to nr of lines */
int fillfrom()
{
frcnt = 0;
strcpy(subject,"");
/* skip until From is found */
while ( lp != NULL && !Isfrom(line)) {
lp = fgets(line, LINELENGTH, f1);
}
if ( NULL == lp ) return(FALSE);
/* copy in first From line */
strcpy(frlist[frcnt] , line);
frcnt++;
/* copy in >From lines */
lp = fgets(line, LINELENGTH, f1);
while ( lp != NULL && Isfrom(line+1)) {
strcpy(frlist[frcnt] , line);
frcnt++;
lp = fgets(line, LINELENGTH, f1);
}
if ( NULL == lp ) return(FALSE);
/* now look through text until ANSWER or start next message */
while ( lp != NULL && !Isfrom(line)) {
line[strlen(line)-1] = '\0'; /* take of CR */
if (equal(line,ANSWER)) break;
lp = fgets(line, LINELENGTH, f1);
}
strcpy(subject,line); /* save last line as dummy subject */
return(TRUE);
}/*fillfrom*/
/* return pointer to string with node name in it */
char *NODE()
{ extern int uname();
static struct utsname name;
uname(&name);
return(name.nodename);
}/*NODE*/
/* make answer file in TEMPA and append $HOME/I_am_out file if exists */
void mkanswer()
{ FILE *f4;
char buf[1024];
register int len;
mktemp(TEMPA);
unlink(TEMPA);
f2 = fopen(TEMPA,"w");
if ( NULL == f2 ) error(ERRTEMPA);
fprintf(f2,"%s\n",ANSWER);
fprintf(f2,"\n");
fprintf(f2,"This is an automatic answering service for Unix mail\n");
fprintf(f2,"Your mail was received at %s ",TIME());
fprintf(f2,"(local time on %s),\n",NODE());
fprintf(f2,"and will be answered by me as soon as I return.\n\n");
fflush(f2);
/* see if we must add $HOME/I_am_out */
sprintf(buf,"%s/I_am_out",getenv("HOME"));
f4 = fopen(buf,"r");
if ( NULL != f4 ) {
do {
len = read (fileno(f4), buf, 1024);
write(fileno(f2), buf, len);
} while (len > 0);
}
fclose(f4);
fclose(f2);
}/*mktemp*/
/* copy mail file to TEMPM so we can process it */
void readmail()
{ char cmd[80];
mktemp(TEMPM);
unlink(TEMPM);
sprintf(cmd,"/bin/mail -p -r >%s 2>/dev/null",TEMPM);
if (DEBUG) printf("cmd=%s\n",cmd);
system(cmd);
}/*readmail*/
/* save message and append to stack_of_mail then delete it */
void savemsg()
{ char cmd[80];
sprintf(cmd,"echo 's %s/mail/stack_of_mail' | /bin/mail -r >/dev/null 2>&1",
getenv("HOME"));
if (DEBUG) printf("cmd=%s\n",cmd);
system(cmd);
}/*savemsg*/
/* check if mail dir has correct access modes x*/
void chkmaildir()
{ char name[80];
sprintf(name,"%s/mail",getenv("HOME"));
if ( access(name, 07) != 0 ) error(ERRNODIR); /* no rwx */
}/*chkmaildir*/
void init()
{
chkmaildir();
mkanswer();
readmail();
/* open mail and read first line */
f1 = fopen(TEMPM,"r");
if ( NULL == f1 ) error(ERRTEMPM);
lp = fgets(line, LINELENGTH, f1);
}
/* return false if needs no answer */
#define MAXIGNORE 16
int needsanswer(FROM)
char FROM[];
{ char *ptr;
FILE *f3;
char *lp3;
extern char *strrchr();
char ignore[MAXIGNORE];
char name[256];
/* check subject if answering service then ignore */
if (equal(subject,ANSWER)) {
strcpy(because,"message from answering service");
return(FALSE);
}
/* ptr must point past last ! */
ptr = strrchr(FROM,'!');
if ( NULL == ptr ) {
ptr = FROM;
} else {
ptr++;
}
/* check for daemons */
if ( (equal (ptr , "**NSC**" )) ||
(equaln(ptr , "NUSEND",6)) ||
(equal (ptr , "uucp" )) ||
(equal (ptr , "**RJE**" )) ||
(equal (ptr , "root" )) ||
(equal (ptr , "daemon" ))
) {
strcpy(because,"it is not a real person");
return(FALSE);
}
/* check if it is you */
if (equal(ptr , getenv("LOGNAME"))) {
strcpy(because,"it is you");
return(FALSE);
}
/* check $HOME/mail/.noanswer file */
sprintf(name,"%s/mail/.noanswer",getenv("HOME"));
f3 = fopen(name,"r");
if ( NULL == f3 ) {
fclose(f3);
return(TRUE);
}
/* now read all entries until EOF or found */
lp3 = fgets(ignore, MAXIGNORE, f3);
while ( lp3 != NULL) {
ignore[strlen(ignore)-1] = '\0'; /* take off CR */
if (equal(ignore,ptr)) {
fclose(f3);
strcpy(because,"it appears in $HOME/mail/.noanswer");
return(FALSE);
}
lp3 = fgets(ignore, MAXIGNORE, f3);
}
fclose(f3);
return(TRUE);
}/*needsanswer*/
void finit()
{
unlink(TEMPA); /* remove TEMPA file */
unlink(TEMPM);
}/*finit*/
/* send reply to TO */
void reply(TO)
char TO[];
{ char cmd[80];
printf("%s anwering %s\n",TIME(),TO);
sprintf(cmd,"/bin/mail '%s' < %s", TO, TEMPA);
if (DEBUG) {
printf("UNEXECUTED cmd=%s\n",cmd);
} else {
system(cmd);
}/*fi*/
}/*reply*/
/* do not send answer to TO */
void noreply(TO)
char TO[];
{
printf("%s No reply to %s because %s\n",TIME(),TO, because);
}/*noreply*/
void usage()
{
printf("Usage: %s [-d] [-v] [-V] [-H]\n",NAME);
}/*usage*/
/* parse options */
void options(argc,argv)
int argc;
char *argv[];
{ register int i;
for ( i = 1 ; i < argc ; i++ ) {
if ( argv[i][0] = '-' ) {
switch (argv[i][1]) {
case 'H': usage();
exit(1);
break;
case 'd': DEBUG = TRUE;
break;
case 'v':
case 'V': printf("%s %s\n",NAME,VERSION);
exit(1);
break;
default: usage();
exit(1);
break;
}/*switch*/
}/*fi*/
}
}/*options*/
int main(argc,argv)
int argc;
char *argv[];
{ char FROM[TOSIZE];
options(argc,argv);
init();
/* now for each message */
while (fillfrom()) {
savemsg(); /* save and then delete message */
strcpy(FROM,frflsh(DEBUG)); /* get FROM */
if (needsanswer(FROM)) {
reply(FROM);
} else {
noreply(FROM);
}/*fi*/
}/*while*/
finit();
return(0);
}/*main*/dat@hpcnof.UUCP (01/13/86)
> The program answer will auto answer your unix mail while you are away. > The best place to run this program from is via crontab(1) of course. I find it hard to believe that I'm the only person who's ever written an autoanswer program that has the following features: 1. It only has one copy running, regardless of how many people are using it on a given machine. 2. It doesn't do anything silly with the incoming mail, like putting it into another file...it doesn't touch the mail at all, in fact. 3. It's FAST AND it recognizes mail sent from itself, so there are no 'loops'... 4. You can bring it down and reboot and it'll work again without loosing track of where it was with anyone... Hmmm... (Have I inspired anyone out there???) -- Dave Taylor Hewlett Packard Corp. ihnp4!hpfcla!d_taylor -or- hpcnof!dat@HPLABS