#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <unistd.h>
#include <utime.h>
#include "error.h"
#include "sig.h"
#include "direntry.h"
#include "control.h"
#include "select.h"
#include "open.h"
#include "seek.h"
#include "exit.h"
#include "lock.h"
#include "ndelay.h"
#include "now.h"
#include "getln.h"
#include "buffer.h"
#include "alloc.h"
#include "genalloc.h"
#include "stralloc.h"
#include "logmsg.h"
#include "str.h"
#include "byte.h"
#include "fmt.h"
#include "scan.h"
#include "case.h"
#include "auto_qmail.h"
#include "auto_queue.h"
#include "trigger.h"
#include "newfield.h"
#include "quote.h"
#include "qmail.h"
#include "qsutil.h"
#include "prioq.h"
#include "constmap.h"
#include "fmtqfn.h"
#include "readsubdir.h"
#include "sendtodo.h"

int lifetime = 604800;
int bouncemaxbytes = 0;

stralloc queuedir = {0};

stralloc percenthack = {0};
struct constmap mappercenthack;
stralloc locals = {0};
struct constmap maplocals;
stralloc vdoms = {0};
struct constmap mapvdoms;
stralloc envnoathost = {0};
stralloc bouncefrom = {0};
stralloc bouncehost = {0};
stralloc doublebounceto = {0};
stralloc doublebouncehost = {0};

char strnum2[FMT_ULONG];
char strnum3[FMT_ULONG];

#define CHANNELS 2
char *chanaddr[CHANNELS] = { "local/", "remote/" };
char *chanstatusmsg[CHANNELS] = { " local ", " remote " };
char *tochan[CHANNELS] = { " to local ", " to remote " };
int chanfdout[CHANNELS] = { 1, 3 };
int chanfdin[CHANNELS] = { 2, 4 };
int chanskip[CHANNELS] = { 10, 20 };

int flagexitasap = 0; void sigterm() { flagexitasap = 1; }
int flagrunasap = 0; void sigalrm() { flagrunasap = 1; }
int flagreadasap = 0; void sighup() { flagreadasap = 1; }

void cleandied() 
{ 
  log1s("alert: qmail-send lost connection to qmail-clean ... exiting\n");
  flagexitasap = 1; 
}

int flagspawnalive[CHANNELS];

void spawndied(int c) 
{ 
  log1s("alert: oh no! qmail-send lost spawn connection! dying...\n");
  flagspawnalive[c] = 0; 
  flagexitasap = 1; 
}

#define REPORTMAX 10000

datetime_sec recent;


/* this file is too long ---------------------------------------- FILE CREATE */

stralloc fn = {0};
stralloc fn2 = {0};
char fnmake_strnum[FMT_ULONG];

void fnmake_init()
{
  while (!stralloc_ready(&fn,FMTQFN)) nomem();
  while (!stralloc_ready(&fn2,FMTQFN)) nomem();
}

void fnmake_info(unsigned long id) { fn.len = fmtqfn(fn.s,"info/",id,1); }
void fnmake_todo(unsigned long id) { fn.len = fmtqfn(fn.s,"todo/",id,1); }
void fnmake_mess(unsigned long id) { fn.len = fmtqfn(fn.s,"mess/",id,1); }
void fnmake_foop(unsigned long id) { fn.len = fmtqfn(fn.s,"foop/",id,0); }
void fnmake_split(unsigned long id) { fn.len = fmtqfn(fn.s,"",id,1); }
void fnmake2_bounce(unsigned long id) { fn2.len = fmtqfn(fn2.s,"bounce/",id,0); }
void fnmake_chanaddr(unsigned long id,int c) { fn.len = fmtqfn(fn.s,chanaddr[c],id,1); }


/* this file is too long ----------------------------------------- REWRITING */

void senderadd(stralloc *sa,char *sender,char *recip)
{
  int i;
  int j;
  int k;

  i = str_len(sender);
  if (i >= 4)
    if (str_equal(sender + i - 4,"-@[]")) {
      j = byte_rchr(sender,i - 4,'@');
      k = str_rchr(recip,'@');
      if (recip[k] && (j + 5 <= i)) {
        /* owner-@host-@[] -> owner-recipbox=reciphost@host */
        while (!stralloc_catb(sa,sender,j)) nomem();
        while (!stralloc_catb(sa,recip,k)) nomem();
        while (!stralloc_cats(sa,"=")) nomem();
        while (!stralloc_cats(sa,recip + k + 1)) nomem();
        while (!stralloc_cats(sa,"@")) nomem();
        while (!stralloc_catb(sa,sender + j + 1,i - 5 - j)) nomem();
        return;
      }
    }
  while (!stralloc_cats(sa,sender)) nomem();
}


/* this file is too long ---------------------------------------------- INFO */

int getinfo(stralloc *sa,datetime_sec *dt,unsigned long id)
{
  int fdnumber;
  struct stat st;
  static stralloc line = {0};
  int match;
  char buf[BUFSIZE_SMALL];
  buffer b;

  fnmake_info(id);
  fdnumber = open_read(fn.s);
  if (fdnumber == -1) return 0;
  if (fstat(fdnumber,&st) == -1) { close(fdnumber); return 0; }
  buffer_init(&b,read,fdnumber,buf,sizeof(buf));
  if (getln(&b,&line,&match,'\0') == -1) { close(fdnumber); return 0; }
  close(fdnumber);
  if (!match) return 0;
  if (line.s[0] != 'F') return 0;

  *dt = st.st_mtime;
  while (!stralloc_copys(sa,line.s + 1)) nomem();
  while (!stralloc_0(sa)) nomem();
  return 1;
}


/* this file is too long ------------------------------------- COMMUNICATION */

buffer toqc; 
char toqcbuf[BUFSIZE_LINE];
buffer fromqc; 
char fromqcbuf[BUFSIZE_LINE];
stralloc comm_buf[CHANNELS] = { {0}, {0} };
int comm_pos[CHANNELS];

void comm_init()
{
  int c;

  buffer_init(&toqc,write,5,toqcbuf,sizeof(toqcbuf));
  buffer_init(&fromqc,read,6,fromqcbuf,sizeof(fromqcbuf));
  for (c = 0; c < CHANNELS; ++c)
    if (ndelay_on(chanfdout[c]) == -1)
    /* this is so stupid: NDELAY semantics should be default on write */
       spawndied(c); /* drastic, but better than risking deadlock */
}

int comm_canwrite(int c)
{
  /* XXX: could allow a bigger buffer; say 10 recipients */
  if (comm_buf[c].s && comm_buf[c].len) return 0;
  return 1;
}

void comm_write(int c,int delnum,unsigned long id,char *sender,char *recip)
{
  char ch;

  if (comm_buf[c].s && comm_buf[c].len) return;
  while (!stralloc_copys(&comm_buf[c],"")) nomem();
  ch = delnum;
  while (!stralloc_append(&comm_buf[c],&ch)) nomem();
  fnmake_split(id);
  while (!stralloc_cats(&comm_buf[c],fn.s)) nomem();
  while (!stralloc_0(&comm_buf[c])) nomem();
  senderadd(&comm_buf[c],sender,recip);
  while (!stralloc_0(&comm_buf[c])) nomem();
  while (!stralloc_cats(&comm_buf[c],recip)) nomem();
  while (!stralloc_0(&comm_buf[c])) nomem();
  comm_pos[c] = 0;
}

void comm_selprep(int *nfds,fd_set *wfds)
{
  int c;

  for (c = 0; c < CHANNELS; ++c)
    if (flagspawnalive[c])
      if (comm_buf[c].s && comm_buf[c].len) {
        FD_SET(chanfdout[c],wfds);
        if (*nfds <= chanfdout[c])
          *nfds = chanfdout[c] + 1;
      }
}

void comm_do(fd_set *wfds)
{
  int c;

  for (c = 0; c < CHANNELS; ++c)
    if (flagspawnalive[c])
      if (comm_buf[c].s && comm_buf[c].len)
        if (FD_ISSET(chanfdout[c],wfds)) {
          int w;
          int len;
          len = comm_buf[c].len;

          w = write(chanfdout[c],comm_buf[c].s + comm_pos[c],len - comm_pos[c]);
          if (w <= 0) {
            if ((w == -1) && (errno == EPIPE))
              spawndied(c);
            else
             continue; /* kernel select() bug; can't avoid busy-looping */
          } else {
           comm_pos[c] += w;
          if (comm_pos[c] == len)
            comm_buf[c].len = 0;
          }
        } 
}


/* this file is too long ------------------------------------------ CLEANUPS */

int flagcleanup; /* if 1, cleanupdir is initialized and ready */
readsubdir cleanupdir;
datetime_sec cleanuptime;

void cleanup_init()
{
  flagcleanup = 0;
  cleanuptime = now();
}

void cleanup_selprep(datetime_sec *wakeup)
{
  if (flagcleanup) *wakeup = 0;
  if (*wakeup > cleanuptime) *wakeup = cleanuptime;
}

void cleanup_do()
{
  char ch;
  struct stat st;
  unsigned long id;

  if (!flagcleanup) {
    if (recent < cleanuptime) return;
    readsubdir_init(&cleanupdir,"mess",pausedir);
    flagcleanup = 1;
  }

  switch (readsubdir_next(&cleanupdir,&id)) {
    case 1:  break; 
    case 0:  flagcleanup = 0; cleanuptime = recent + SLEEP_CLEANUP;
    default: return;
  }

  fnmake_mess(id);
  if (stat(fn.s,&st) == -1) return; /* probably qmail-queue deleted it */
  if (recent <= st.st_atime + OSSIFIED) return;

  fnmake_info(id);
  if (stat(fn.s,&st) == 0) return;
  if (errno != ENOENT) return;

  fnmake_todo(id);
  if (stat(fn.s,&st) == 0) return;
  if (errno != ENOENT) return;

  fnmake_foop(id);
  if (buffer_putflush(&toqc,fn.s,fn.len) == -1) { cleandied(); return; }
  if (buffer_get(&fromqc,&ch,1) != 1) { cleandied(); return; }
  if (ch != '+')
    log3s("warning: qmail-clean is unable to clean up ",fn.s,"\n");
}


/* this file is too long ----------------------------------- PRIORITY QUEUES */

prioq pqdone = {0}; /* -todo +info; HOPEFULLY -local -remote */
prioq pqchan[CHANNELS] = { {0}, {0} };
/* pqchan 0: -todo +info +local ?remote */
/* pqchan 1: -todo +info ?local +remote */
prioq pqfail = {0}; /* stat() failure; has to be pqadded again */

void pqadd(unsigned long id)
{
  struct prioq_elt pe;
  struct prioq_elt pechan[CHANNELS];
  int flagchan[CHANNELS];
  struct stat st;
  int c;

#define CHECKSTAT if (errno != ENOENT) goto FAIL;

  fnmake_info(id);
  if (stat(fn.s,&st) == -1) {
    CHECKSTAT
    return; /* someone yanking our chain */
  }

  fnmake_todo(id);
  if (stat(fn.s,&st) != -1) return; /* look, ma, dad crashed writing info! */
  CHECKSTAT

  for (c = 0; c < CHANNELS; ++c) {
    fnmake_chanaddr(id,c);
    if (stat(fn.s,&st) == -1) { flagchan[c] = 0; CHECKSTAT }
    else { flagchan[c] = 1; pechan[c].id = id; pechan[c].dt = st.st_mtime; }
  }

  for (c = 0; c < CHANNELS; ++c)
    if (flagchan[c])
      while (!prioq_insert(&pqchan[c],&pechan[c])) nomem();

  for (c = 0; c < CHANNELS; ++c) 
    if (flagchan[c]) break;

  if (c == CHANNELS) {
    pe.id = id; pe.dt = now();
    while (!prioq_insert(&pqdone,&pe)) nomem();
  }

  return;

  FAIL:
  log3s("warning: qmail-send send is unable to stat ",fn.s,"; will try again later\n");
  pe.id = id; pe.dt = now() + SLEEP_SYSFAIL;
  while (!prioq_insert(&pqfail,&pe)) nomem();
}

void pqstart()
{
  readsubdir rs;
  int x;
  unsigned long id;

  readsubdir_init(&rs,"info",pausedir);

  while ((x = readsubdir_next(&rs,&id)))
    if (x > 0) pqadd(id);
}

void pqfinish()
{
  int c;
  struct prioq_elt pe;
  time_t ut[2]; /* XXX: more portable than utimbuf, but still worrisome */

  for (c = 0; c < CHANNELS; ++c)
    while (prioq_min(&pqchan[c],&pe)) {
      prioq_delmin(&pqchan[c]);
      fnmake_chanaddr(pe.id,c);
      ut[0] = ut[1] = pe.dt;
      if (utime(fn.s,ut) == -1)
        log3s("warning: qmail-send is unable to utime ",fn.s,"; message will be retried too soon\n");
    }
}

void pqrun()
{
  int c;
  int i;

  for (c = 0; c < CHANNELS; ++c)
    if (pqchan[c].p)
      if (pqchan[c].len)
        for (i = 0; i < pqchan[c].len; ++i)
	  pqchan[c].p[i].dt = recent;
}


/* this file is too long ---------------------------------------------- JOBS */

struct job
{
  int refs;           /* if 0, this struct is unused */
  unsigned long id;
  int channel;
  datetime_sec retry;
  stralloc sender;
  int numtodo;
  int flaghiteof;
  int flagdying;
};

int numjobs;
struct job *jo;

void job_init()
{
  int j;

  while (!(jo = (struct job *) alloc(numjobs * sizeof(struct job)))) nomem();
  for (j = 0; j < numjobs; ++j) {
    jo[j].refs = 0;
    jo[j].sender.s = 0;
  }
}

int job_avail()
{
  int j;

  for (j = 0; j < numjobs; ++j) 
    if (!jo[j].refs) return 1;
  return 0;
}

int job_open(unsigned long id,int channel)
{
  int j;

  for (j = 0; j < numjobs; ++j) 
    if (!jo[j].refs) break;
  if (j == numjobs) return -1;
  jo[j].refs = 1;
  jo[j].id = id;
  jo[j].channel = channel;
  jo[j].numtodo = 0;
  jo[j].flaghiteof = 0;
  return j;
}

void job_close(int j)
{
  struct prioq_elt pe;
  struct stat st;
  int c;

  if (0 < --jo[j].refs) return;

  pe.id = jo[j].id;
  pe.dt = jo[j].retry;

  if (jo[j].flaghiteof && !jo[j].numtodo) {
    fnmake_chanaddr(jo[j].id,jo[j].channel);
    if (unlink(fn.s) == -1) {
      log3s("warning: qmail-send is unable to unlink ",fn.s,"; will try again later\n");
      pe.dt = now() + SLEEP_SYSFAIL;
    } else {
      for (c = 0; c < CHANNELS; ++c) if (c != jo[j].channel) {
        fnmake_chanaddr(jo[j].id,c);
        if (stat(fn.s,&st) == 0) return; /* more channels going */
        if (errno != ENOENT) {
          log3s("warning: qmail-send is unable to stat ",fn.s,"\n");
          break; /* this is the only reason for HOPEFULLY */
        }
    }
    pe.dt = now();
    while (!prioq_insert(&pqdone,&pe)) nomem();
    return;
    }
  }

  while (!prioq_insert(&pqchan[jo[j].channel],&pe)) nomem();
}


/* this file is too long ------------------------------------------- BOUNCES */

char *stripvdomprepend(char *recip)
{
  int i;
  char *domain;
  int domainlen;
  char *prepend;

  i = str_rchr(recip,'@');
  if (!recip[i]) return recip;
  domain = recip + i + 1;
  domainlen = str_len(domain);

  for (i = 0; i <= domainlen; ++i)
    if ((i == 0) || (i == domainlen) || (domain[i] == '.'))
      if ((prepend = constmap(&mapvdoms,domain + i,domainlen - i))) {
        if (!*prepend) break;
        i = str_len(prepend);
        if (str_diffn(recip,prepend,i)) break;
        if (recip[i] != '-') break;
        return recip + i + 1;
      }

  return recip;
}

stralloc bouncetext = {0};

void addbounce(unsigned long id,char *recip,char *report)
{
  int fd;
  int pos;
  int w;

  while (!stralloc_copys(&bouncetext,"<")) nomem();
  while (!stralloc_cats(&bouncetext,stripvdomprepend(recip))) nomem();

  for (pos = 0; pos < bouncetext.len; ++pos)
    if (bouncetext.s[pos] == '\n')
      bouncetext.s[pos] = '_';

  while (!stralloc_cats(&bouncetext,">:\n")) nomem();
  while (!stralloc_cats(&bouncetext,report)) nomem();

  if (report[0])
    if (report[str_len(report) - 1] != '\n')
      while (!stralloc_cats(&bouncetext,"\n")) nomem();

  for (pos = bouncetext.len - 2; pos > 0; --pos)
    if (bouncetext.s[pos] == '\n')
      if (bouncetext.s[pos - 1] == '\n')
        bouncetext.s[pos] = '/';

  while (!stralloc_cats(&bouncetext,"\n")) nomem();
  fnmake2_bounce(id);

  for (;;) {
    fd = open_append(fn2.s);
    if (fd != -1) break;
    log1s("alert: qmail-send is unable to append to bounce message; HELP! sleeping...\n");
    sleep(10);
  }

  pos = 0;

  while (pos < bouncetext.len) {
    w = write(fd,bouncetext.s + pos,bouncetext.len - pos);
    if (w <= 0) {
      log1s("alert: qmail-send is unable to append to bounce message; HELP! sleeping...\n");
      sleep(10);
    }
    else
      pos += w;
  }
  close(fd);
}

int injectbounce(unsigned long id)
{
  struct qmail qqt;
  struct stat st;
  char *bouncesender;
  char *bouncerecip;
  int r;
  int fd;
  buffer bi;
  char buf[BUFSIZE_SMALL];
  char inbuf[BUFSIZE_SMALL];
  static stralloc sender = {0};
  static stralloc quoted = {0};
  datetime_sec birth;
  unsigned long qp;
  int bytestogo;
  int bytestoget;

  if (!getinfo(&sender,&birth,id)) return 0; /* XXX: print warning */

  /* owner-@host-@[] -> owner-@host */
  if (sender.len >= 5)
    if (str_equal(sender.s + sender.len - 5,"-@[]")) {
      sender.len -= 4;
      sender.s[sender.len - 1] = 0;
    }

  fnmake2_bounce(id);
  fnmake_mess(id);

  if (stat(fn2.s,&st) == -1) {
    if (errno == ENOENT) return 1;
    log3s("warning: qmail-send is unable to stat ",fn2.s,"\n");
    return 0;
  }
 
  if (str_equal(sender.s,"#@[]"))
    log3s("triple bounce: discarding ",fn2.s,"\n");
  else if (!*sender.s && *doublebounceto.s == '@') 
    log3s("double bounce: discarding ",fn2.s,"\n");
  else {
    if (qmail_open(&qqt) == -1)
      { log1s("warning: qmail-send is unable to start qmail-queue, will try later\n"); return 0; }
    qp = qmail_qp(&qqt);

    if (*sender.s) { bouncesender = ""; bouncerecip = sender.s; }
    else { bouncesender = "#@[]"; bouncerecip = doublebounceto.s; }

    while (!newfield_datemake(now())) nomem();
    qmail_put(&qqt,newfield_date.s,newfield_date.len);
    qmail_puts(&qqt,"From: ");
    while (!quote(&quoted,&bouncefrom)) nomem();
    qmail_put(&qqt,quoted.s,quoted.len);
    qmail_puts(&qqt,"@");
    qmail_put(&qqt,bouncehost.s,bouncehost.len);
    qmail_puts(&qqt,"\nTo: ");
    while (!quote2(&quoted,bouncerecip)) nomem();
    qmail_put(&qqt,quoted.s,quoted.len);
    qmail_puts(&qqt,"\n\
Subject: failure notice\n\
\n\
Hi. This is the qmail-send program at ");
   qmail_put(&qqt,bouncehost.s,bouncehost.len);
   qmail_puts(&qqt,*sender.s ? ".\n\
I'm afraid I wasn't able to deliver your message to the following addresses.\n\
This is a permanent error; I've given up. Sorry it didn't work out.\n\
\n\
" : ".\n\
I tried to deliver a bounce message to this address, but the bounce bounced!\n\
\n\
");

    fd = open_read(fn2.s);
    if (fd == -1)
    	qmail_fail(&qqt);
    else {
      buffer_init(&bi,read,fd,inbuf,sizeof(inbuf));
      while ((r = buffer_get(&bi,buf,sizeof(buf))) > 0)
        qmail_put(&qqt,buf,r);

      close(fd);
      if (r == -1) qmail_fail(&qqt);
    }

    qmail_puts(&qqt,*sender.s ? "--- Below this line is a copy of the message.\n\n" : "--- Below this line is the original bounce.\n\n");
    qmail_puts(&qqt,"Return-Path: <");
    while (!quote2(&quoted,sender.s)) nomem();
    qmail_put(&qqt,quoted.s,quoted.len);
    qmail_puts(&qqt,">\n");

    fd = open_read(fn.s);
    if (fd == -1) 
      qmail_fail(&qqt);
    else {
      if (bouncemaxbytes) {
        bytestogo = bouncemaxbytes;
        bytestoget = (bytestogo < sizeof(buf)) ? bytestogo : sizeof(buf);

        buffer_init(&bi,read,fd,inbuf,sizeof(inbuf));

        while (bytestoget > 0 && (r = buffer_get(&bi,buf,bytestoget)) > 0) {
          qmail_put(&qqt,buf,r);
          bytestogo -= bytestoget;
          bytestoget = (bytestogo < sizeof(buf)) ? bytestogo : sizeof(buf);
        }
        if (r > 0) 
          qmail_puts(&qqt,"\n\n--- Rest of message truncated.\n");
        } else {                      /* preserve default behavior */
          buffer_init(&bi,read,fd,inbuf,sizeof(inbuf));

          while ((r = buffer_get(&bi,buf,sizeof(buf))) > 0)
           qmail_put(&qqt,buf,r);
        }
        close(fd);
        if (r == -1) qmail_fail(&qqt);
    }

    qmail_from(&qqt,bouncesender);
    qmail_to(&qqt,bouncerecip);

    if (*qmail_close(&qqt)) { 
      log1s("warning: qmail-send has trouble injecting bounce message, will try later\n");
      return 0; 
    }

    strnum2[fmt_ulong(strnum2,id)] = 0;
    log2s("bounce msg ",strnum2);
    strnum2[fmt_ulong(strnum2,qp)] = 0;
    log3s(" qp ",strnum2,"\n");
  }

  if (unlink(fn2.s) != 0) {
    log3s("warning: qmail-send is unable to unlink ",fn2.s,"\n");
    return 0;
  }

  return 1;
}


/* this file is too long ---------------------------------------- DELIVERIES */

struct del {
  int used;
  int j;
  unsigned long delid;
  seek_pos mpos;
  stralloc recip;
};

unsigned long masterdelid = 1;
unsigned int concurrency[CHANNELS] = { 10, 20 };
unsigned int concurrencyused[CHANNELS] = { 0, 0 };
struct del *d[CHANNELS];
stralloc dline[CHANNELS];
char delbuf[2048];

void del_status()
{
  int c;

  log1s("status:");
  for (c = 0; c < CHANNELS; ++c) {
    strnum2[fmt_ulong(strnum2,(unsigned long) concurrencyused[c])] = 0;
    strnum3[fmt_ulong(strnum3,(unsigned long) concurrency[c])] = 0;
    log2s(chanstatusmsg[c],strnum2);
    log2s("/",strnum3);
  }
  if (flagexitasap) log1s(" exitasap");
  log1s("\n");
}

void del_init()
{
  int c;
  int i;

  for (c = 0; c < CHANNELS; ++c) {
    flagspawnalive[c] = 1;
    while (!(d[c] = (struct del *) alloc(concurrency[c] * sizeof(struct del))))
      nomem();
    for (i = 0; i < concurrency[c]; ++i)
      { d[c][i].used = 0; d[c][i].recip.s = 0; }
   dline[c].s = 0;
   while (!stralloc_copys(&dline[c],"")) nomem();
  }

  del_status();
}

int del_canexit()
{
  int c;

  for (c = 0; c < CHANNELS; ++c)
   if (flagspawnalive[c]) /* if dead, nothing we can do about its jobs */
     if (concurrencyused[c]) return 0;
  return 1;
}

int del_avail(int c)
{
  return flagspawnalive[c] && comm_canwrite(c) && (concurrencyused[c] < concurrency[c]);
}

void del_start(int j,seek_pos mpos,char *recip)
{
  int i;
  int c;

  c = jo[j].channel;
  if (!flagspawnalive[c]) return;
  if (!comm_canwrite(c)) return;

  for (i = 0; i < concurrency[c]; ++i) 
    if (!d[c][i].used) break;
  if (i == concurrency[c]) return;

  if (!stralloc_copys(&d[c][i].recip,recip)) { nomem(); return; }
  if (!stralloc_0(&d[c][i].recip)) { nomem(); return; }
  d[c][i].j = j; ++jo[j].refs;
  d[c][i].delid = masterdelid++;
  d[c][i].mpos = mpos;
  d[c][i].used = 1; ++concurrencyused[c];

  comm_write(c,i,jo[j].id,jo[j].sender.s,recip);

  strnum2[fmt_ulong(strnum2,d[c][i].delid)] = 0;
  strnum3[fmt_ulong(strnum3,jo[j].id)] = 0;
  log2s("starting delivery ",strnum2);
  log3s(": msg ",strnum3,tochan[c]);
  logsafe(recip);
  log1s("\n");
  del_status();
}

void markdone(int c,unsigned long id,seek_pos pos)
{
  struct stat st;
  int fd;

  fnmake_chanaddr(id,c);

  for (;;) {
    fd = open_write(fn.s);
    if (fd == -1) break;
    if (fstat(fd,&st) == -1) { close(fd); break; }
    if (seek_set(fd,pos) == -1) { close(fd); break; }
    if (write(fd,"D",1) != 1) { close(fd); break; }
    /* further errors -> double delivery without us knowing about it, oh well */
    close(fd);
    return;
  }
  log3s("warning: qmail-send has trouble marking ",fn.s,"; message will be delivered twice!\n");
}

void del_dochan(int c)
{
  int r;
  char ch;
  int i;
  int delnum;
 
  r = read(chanfdin[c],delbuf,sizeof(delbuf));
  if (r == -1) return;
  if (r == 0) { spawndied(c); return; }

  for (i = 0; i < r; ++i) {
    ch = delbuf[i];
    while (!stralloc_append(&dline[c],&ch)) nomem();
    
    if (dline[c].len > REPORTMAX)
      dline[c].len = REPORTMAX;
      /* qmail-lspawn and qmail-rspawn are responsible for keeping it short */
      /* but from a security point of view, we don't trust rspawn */

    if (!ch && (dline[c].len > 1)) {
      delnum = (unsigned int) (unsigned char) dline[c].s[0];
      if ((delnum < 0) || (delnum >= concurrency[c]) || !d[c][delnum].used)
        log1s("warning: qmail-send's internal error: delivery report out of range\n");
      else {
        strnum3[fmt_ulong(strnum3,d[c][delnum].delid)] = 0;
        if (dline[c].s[1] == 'Z')
	    if (jo[d[c][delnum].j].flagdying) {
	      dline[c].s[1] = 'D';
	      --dline[c].len;
	      while (!stralloc_cats(&dline[c],"I'm not going to try again; this message has been in the queue too long.\n")) nomem();
	      while (!stralloc_0(&dline[c])) nomem();
	    }

        switch (dline[c].s[1]) {
          case 'K':
            log3s("delivery ",strnum3,": success: ");
            logsafe(dline[c].s + 2);
            log1s("\n");
            markdone(c,jo[d[c][delnum].j].id,d[c][delnum].mpos);
            --jo[d[c][delnum].j].numtodo;
           break;
         case 'Z':
           log3s("delivery ",strnum3,": deferral: ");
           logsafe(dline[c].s + 2);
           log1s("\n");
           break;
         case 'D':
           log3s("delivery ",strnum3,": failure: ");
           logsafe(dline[c].s + 2);
           log1s("\n");
           addbounce(jo[d[c][delnum].j].id,d[c][delnum].recip.s,dline[c].s + 2);
           markdone(c,jo[d[c][delnum].j].id,d[c][delnum].mpos);
           --jo[d[c][delnum].j].numtodo;
           break;
         default:
           log3s("delivery ",strnum3,": report mangled, will defer\n");
       }
        
      job_close(d[c][delnum].j);
      d[c][delnum].used = 0; --concurrencyused[c];
        del_status();
     
      }
      dline[c].len = 0;
    }
  }
}

void del_selprep(int *nfds,fd_set *rfds)
{
  int c;

  for (c = 0; c < CHANNELS; ++c)
    if (flagspawnalive[c]) {
      FD_SET(chanfdin[c],rfds);
      if (*nfds <= chanfdin[c])
        *nfds = chanfdin[c] + 1;
    }
}

void del_do(fd_set *rfds)
{
  int c;

  for (c = 0; c < CHANNELS; ++c)
    if (flagspawnalive[c])
      if (FD_ISSET(chanfdin[c],rfds))
        del_dochan(c);
}


/* this file is too long -------------------------------------------- PASSES */

struct
{
  unsigned long id; /* if 0, need a new pass */
  int j;            /* defined if id; job number */
  int fd;           /* defined if id; reading from {local,remote} */
  seek_pos mpos;    /* defined if id; mark position */
  buffer b;
  char buf[BUFSIZE_SMALL];
}
pass[CHANNELS];

void pass_init()
{
  int c;

  for (c = 0; c < CHANNELS; ++c) pass[c].id = 0;
}

void pass_selprep(datetime_sec *wakeup)
{
  int c;
  struct prioq_elt pe;
  if (flagexitasap) return;
 
  for (c = 0; c < CHANNELS; ++c)
    if (pass[c].id)
      if (del_avail(c))
       { *wakeup = 0; return; }
  
  if (job_avail())
    for (c = 0; c < CHANNELS; ++c)
      if (!pass[c].id)
        if (prioq_min(&pqchan[c],&pe))
          if (*wakeup > pe.dt) *wakeup = pe.dt;
  
  if (prioq_min(&pqfail,&pe))
    if (*wakeup > pe.dt)
      *wakeup = pe.dt;

  if (prioq_min(&pqdone,&pe))
    if (*wakeup > pe.dt)*wakeup = pe.dt;
}

static datetime_sec squareroot(datetime_sec x) /* result^2 <= x < (result + 1)^2 ;  assuming: >= 0 */
{
  datetime_sec y;
  datetime_sec yy;
  datetime_sec y21;
  int j;

  y = 0; yy = 0;
  for (j = 15; j >= 0; --j) {
    y21 = (y << (j + 1)) + (1 << (j + j));
    if (y21 <= x - yy) { y += (1 << j); yy += y21; }
  }
  return y;
}

datetime_sec nextretry(datetime_sec birth,int c)
{
  int n;

  if (birth > recent) n = 0;
  else n = squareroot(recent - birth); /* no need to add fuzz to recent */

  n += chanskip[c];
  return birth + n * n;
}

void pass_dochan(int c)
{
  datetime_sec birth;
  struct prioq_elt pe;
  static stralloc line = {0};
  int match;

  if (flagexitasap) return;

  if (!pass[c].id) {
    if (!job_avail()) return;
    if (!prioq_min(&pqchan[c],&pe)) return;
    if (pe.dt > recent) return;
    fnmake_chanaddr(pe.id,c);

    prioq_delmin(&pqchan[c]);
    pass[c].mpos = 0;
    pass[c].fd = open_read(fn.s);
    if (pass[c].fd == -1) goto trouble;
    if (!getinfo(&line,&birth,pe.id)) { close(pass[c].fd); goto trouble; }
    pass[c].id = pe.id;
    buffer_init(&pass[c].b,read,pass[c].fd,pass[c].buf,sizeof(pass[c].buf));
    pass[c].j = job_open(pe.id,c);
    jo[pass[c].j].retry = nextretry(birth,c);
    jo[pass[c].j].flagdying = (recent > birth + lifetime);
    while (!stralloc_copy(&jo[pass[c].j].sender,&line)) nomem();
  }

  if (!del_avail(c)) return;

  if (getln(&pass[c].b,&line,&match,'\0') == -1) {
    fnmake_chanaddr(pass[c].id,c);
    log3s("warning: qmail-send has trouble reading ",fn.s,"; will try again later\n");
    close(pass[c].fd);
    job_close(pass[c].j);
    pass[c].id = 0;
    return;
  }

  if (!match) {
    close(pass[c].fd);
    jo[pass[c].j].flaghiteof = 1;
    job_close(pass[c].j);
    pass[c].id = 0;
    return;
  }

  switch (line.s[0]) {
    case 'T':
      ++jo[pass[c].j].numtodo;
      del_start(pass[c].j,pass[c].mpos,line.s + 1);
      break;
    case 'D':
      break;
    default:
      fnmake_chanaddr(pass[c].id,c);
      log3s("warning: qmail-send recognizes unknown record type in ",fn.s,"!\n");
      close(pass[c].fd);
      job_close(pass[c].j);
      pass[c].id = 0;
      return;
   }

  pass[c].mpos += line.len;
  return;

  trouble:
  log3s("warning: qmail-send has trouble opening ",fn.s,"; will try again later\n");
  pe.dt = recent + SLEEP_SYSFAIL;
  while (!prioq_insert(&pqchan[c],&pe)) nomem();
}

void messdone(unsigned long id)
{
  char ch;
  int c;
  struct prioq_elt pe;
  struct stat st;

  for (c = 0; c < CHANNELS; ++c) {
    fnmake_chanaddr(id,c);
    if (stat(fn.s,&st) == 0) return; /* false alarm; consequence of HOPEFULLY */
    if (errno != ENOENT) {
      log3s("warning: qmail-send is unable to stat ",fn.s,"; will try again later\n");
      goto FAIL;
    }
  }

  fnmake_todo(id);
  if (stat(fn.s,&st) == 0) return;
  if (errno != ENOENT) {
    log3s("warning: qmail-send is unable to stat ",fn.s,"; will try again later\n");
    goto FAIL;
   }
 
  fnmake_info(id);
  if (stat(fn.s,&st) == -1) {
    if (errno == ENOENT) return;
    log3s("warning: qmail-send is unable to stat ",fn.s,"; will try again later\n");
    goto FAIL;
  }
 
 /* -todo +info -local -remote ?bounce */
  if (!injectbounce(id))
    goto FAIL; /* injectbounce() produced error message */

  strnum3[fmt_ulong(strnum3,id)] = 0;
  log3s("end msg ",strnum3,"\n");

 /* -todo +info -local -remote -bounce */
  fnmake_info(id);
  if (unlink(fn.s) == -1) {
    log3s("warning: qmail-send is unable to unlink ",fn.s,"; will try again later\n");
    goto FAIL;
  }

 /* -todo -info -local -remote -bounce; we can relax */
  fnmake_foop(id);
  if (buffer_putflush(&toqc,fn.s,fn.len) == -1) { cleandied(); return; }
  if (buffer_get(&fromqc,&ch,1) != 1) { cleandied(); return; }
  if (ch != '+') log3s("warning: qmail-clean unable to clean up ",fn.s,"\n");

  return;

  FAIL:
  pe.id = id; pe.dt = now() + SLEEP_SYSFAIL;
  while (!prioq_insert(&pqdone,&pe)) nomem();
}

void pass_do()
{
  int c;
  struct prioq_elt pe;

  for (c = 0; c < CHANNELS; ++c) 
    pass_dochan(c);

  if (prioq_min(&pqfail,&pe))
    if (pe.dt <= recent) {
      prioq_delmin(&pqfail);
      pqadd(pe.id);
    }

  if (prioq_min(&pqdone,&pe))
    if (pe.dt <= recent) {
      prioq_delmin(&pqdone);
      messdone(pe.id);
     }
}


/* this file is too long ------------------------------------- EXTERNAL TODO */

stralloc todoline = {0};
char todobuf[2048];
int todofdin;
int todofdout;
int flagtodoalive;

void tododied() { 
 log1s("alert: qmail-send lost connection to qmail-todo ... exiting\n");
 flagexitasap = 1; 
 flagtodoalive = 0;
}

void todo_init()
{
  todofdout = 7;
  todofdin = 8;
  flagtodoalive = 1;
  /* sync with external todo */
  if (write(todofdout,"S",1) != 1) tododied();
  
  return;
}

void todo_selprep(int *nfds,fd_set *rfds,datetime_sec *wakeup)
{
  if (flagexitasap) {
    if (flagtodoalive) {
      write(todofdout,"X",1);
    }
  }
  if (flagtodoalive) {
    FD_SET(todofdin,rfds);
    if (*nfds <= todofdin)
      *nfds = todofdin + 1;
  }
}

void todo_del(char* s)
{
 int flagchan[CHANNELS];
 struct prioq_elt pe;
 unsigned long id;
 unsigned int len;
 int c;

 for (c = 0; c < CHANNELS; ++c) 
  flagchan[c] = 0;

 switch (*s++) {
  case 'L':
    flagchan[0] = 1;
    break;
  case 'R':
    flagchan[1] = 1;
    break;
  case 'B':
    flagchan[0] = 1;
    flagchan[1] = 1;
    break;
  case 'X':
    break;
  default:
    log1s("warning: qmail-send is unable to understand qmail-todo\n");
    return;
 }
 
 len = scan_ulong(s,&id);
 if (!len || s[len]) {
  log1s("warning: qmail-send is unable to understand qmail-todo\n");
  return;
 }

 pe.id = id; pe.dt = now();
 for (c = 0; c < CHANNELS; ++c)
   if (flagchan[c])
     while (!prioq_insert(&pqchan[c],&pe)) nomem();

 for (c = 0; c < CHANNELS; ++c) 
  if (flagchan[c]) break;

 if (c == CHANNELS)
   while (!prioq_insert(&pqdone,&pe)) nomem();

 return;
}

void todo_do(fd_set *rfds)
{
  int r;
  char ch;
  int i;
  
  if (!flagtodoalive) return;
  if (!FD_ISSET(todofdin,rfds)) return;

  r = read(todofdin,todobuf,sizeof(todobuf));
  if (r == -1) return;
  if (r == 0) {
    if (flagexitasap)
      flagtodoalive = 0;
    else
      tododied();
    return;
  }

  for (i = 0; i < r; ++i) {
    ch = todobuf[i];
    while (!stralloc_append(&todoline,&ch)) nomem();
    if (todoline.len > REPORTMAX)
      todoline.len = REPORTMAX;
      /* qmail-todo is responsible for keeping it short */
    if (!ch && (todoline.len > 1)) {
      switch (todoline.s[0]) {
	case 'D':
	  if (flagexitasap) break;
	  todo_del(todoline.s + 1);
	  break;
	case 'L':
	  log1s(todoline.s + 1);
	  break;
	case 'X':
	  if (flagexitasap)
	    flagtodoalive = 0;
	  else
	    tododied();
	  break;
	default:
	  log1s("warning: qmail-send is unable to understand qmail-todo: report mangled\n");
	  break;
      }
      todoline.len = 0;
    }
  }
}

/* this file is too long ---------------------------------------------- MAIN */

int getcontrols() 
{ 
  if (control_init() == -1) return 0;
  if (control_readint(&lifetime,"control/queuelifetime") == -1) return 0;
  if (control_readint(&concurrency[0],"control/concurrencylocal") == -1) return 0;
  if (control_readint(&concurrency[1],"control/concurrencyremote") == -1) return 0;
  if (control_rldef(&envnoathost,"control/envnoathost",1,"envnoathost") != 1) return 0;
  if (control_rldef(&bouncefrom,"control/bouncefrom",0,"MAILER-DAEMON") != 1) return 0;
  if (control_rldef(&bouncehost,"control/bouncehost",1,"bouncehost") != 1) return 0;
  if (control_readint(&bouncemaxbytes,"control/bouncemaxbytes") == -1) return 0;   
  if (control_rldef(&doublebouncehost,"control/doublebouncehost",1,"doublebouncehost") != 1) return 0;
  if (control_rldef(&doublebounceto,"control/doublebounceto",0,"postmaster") != 1) return 0;
  if (!stralloc_cats(&doublebounceto,"@")) return 0;
  if (!stralloc_cat(&doublebounceto,&doublebouncehost)) return 0;
  if (!stralloc_0(&doublebounceto)) return 0;
  if (control_readfile(&locals,"control/locals",1) != 1) return 0;
  if (!constmap_init(&maplocals,locals.s,locals.len,0)) return 0;
  switch (control_readfile(&percenthack,"control/percenthack",0)) {
    case -1: return 0;
    case  0: if (!constmap_init(&mappercenthack,"",0,0)) return 0; break;
    case  1: if (!constmap_init(&mappercenthack,percenthack.s,percenthack.len,0)) return 0; break;
  }
  switch (control_readfile(&vdoms,"control/virtualdomains",0)) {
    case -1: return 0;
    case  0: if (!constmap_init(&mapvdoms,"",0,1)) return 0; break;
    case  1: if (!constmap_init(&mapvdoms,vdoms.s,vdoms.len,1)) return 0; break;
  }
  return 1; 
}

stralloc newlocals = {0};
stralloc newvdoms = {0};

void regetcontrols()
{
  int r;

  if (control_readfile(&newlocals,"control/locals",1) != 1) { log1s("alert: qmail-send is unable to reread control/locals\n"); return; }
  if (control_readint(&concurrency[0],"control/concurrencylocal") == -1) { log1s("alert: qmail-send is unable to reread control/concurrencylocal\n"); return; }
  if (control_readint(&concurrency[1],"control/concurrencyremote") == -1) { log1s("alert: qmail-send is unable to reread control/concurrencyremote\n"); return; }
  if (control_readint(&lifetime,"control/queuelifetime") == -1) { log1s("alert: qmail-send is unable to reread control/queuelifetime\n"); return; }

  r = control_readfile(&newvdoms,"control/virtualdomains",0);
  if (r == -1) { log1s("alert: qmail-send is unable to reread control/virtualdomains\n"); return; }

  constmap_free(&maplocals);
  constmap_free(&mapvdoms);

  while (!stralloc_copy(&locals,&newlocals)) nomem();
  while (!constmap_init(&maplocals,locals.s,locals.len,0)) nomem();

  if (r) {
    while (!stralloc_copy(&vdoms,&newvdoms)) nomem();
    while (!constmap_init(&mapvdoms,vdoms.s,vdoms.len,1)) nomem();
  } else
    while (!constmap_init(&mapvdoms,"",0,1)) nomem();
}

void reread()
{
  if (chdir(auto_qmail) == -1) {
    log1s("alert: qmail-send is unable to reread controls: unable to switch to home directory\n");
    return;
  }
  write(todofdout,"H",1);
  regetcontrols();

  while (chdir(queuedir.s) == -1) {
    log1s("alert: qmail-send is unable to switch back to queue directory; HELP! sleeping...\n");
    sleep(10);
  }
}

int main()
{
  int fd;
  datetime_sec wakeup;
  fd_set rfds;
  fd_set wfds;
  int nfds;
  struct timeval tv;
  int c;
  int u;
  int r;
  char ch;
  
  if (!stralloc_copys(&queuedir,auto_queue)) _exit(110);
  if (!stralloc_cats(&queuedir,"/queue")) _exit(110);
  if (!stralloc_0(&queuedir)) _exit(110);

  if (chdir(auto_qmail) == -1) { log3s("alert: qmail-send is unable to switch to home directory ",auto_qmail,"\n"); _exit(110); }
  if (!getcontrols()) { log1s("alert: qmail-send is unable to read controls\n"); _exit(111); }
  if (chdir(queuedir.s) == -1) { log3s("alert: qmail-send cannot start and is unable to switch to queue directory ",queuedir.s,"\n"); _exit(110); }
  sig_pipeignore();
  sig_termcatch(sigterm);
  sig_alarmcatch(sigalrm);
  sig_hangupcatch(sighup);
  sig_childdefault();
  umask(077);

  fd = open_write("lock/sendmutex");
  if (fd == -1) { log1s("alert: qmail-send is unable to open mutex\n"); _exit(111); }
  if (lock_exnb(fd) == -1) { log1s("alert: qmail-send is already running\n"); _exit(111); }

  numjobs = 0;
  for (c = 0;c < CHANNELS;++c) {
    do
      r = read(chanfdin[c],&ch,1);

    while ((r == -1) && (errno == EINTR));
    if (r < 1) { log1s("alert: cannot start: hath the daemon spawn no fire?\n"); _exit(111); }

    u = (unsigned int) (unsigned char) ch;
    if (concurrency[c] > u) concurrency[c] = u;
    numjobs += concurrency[c];
  }

  fnmake_init();

  comm_init();

  pqstart();
  job_init();
  del_init();
  pass_init();
  todo_init();
  cleanup_init();

  while (!flagexitasap || !del_canexit() || flagtodoalive) {
    recent = now();

    if (flagrunasap) { flagrunasap = 0; pqrun(); }
    if (flagreadasap) { flagreadasap = 0; reread(); }

    wakeup = recent + SLEEP_FOREVER;
    FD_ZERO(&rfds);
    FD_ZERO(&wfds);
    nfds = 1;

    comm_selprep(&nfds,&wfds);
    del_selprep(&nfds,&rfds);
    pass_selprep(&wakeup);
    todo_selprep(&nfds,&rfds,&wakeup);
    cleanup_selprep(&wakeup);

    if (wakeup <= recent) tv.tv_sec = 0;
    else tv.tv_sec = wakeup - recent + SLEEP_FUZZ;
    tv.tv_usec = 0;

    if (select(nfds,&rfds,&wfds,(fd_set *) 0,&tv) == -1)
      if (errno == EINTR)
        ;
      else
        log1s("warning: qmail-send has trouble in select\n");
    else {
      recent = now();

      comm_do(&wfds);
      del_do(&rfds);
      todo_do(&rfds);
      pass_do();
      cleanup_do();
    }
  }
 
  pqfinish();
  log1s("status: qmail-send exiting\n");
  _exit(0);
}