//實用工具程序之一，作用：將在maildir格式郵箱中的消息轉換到一個標準的sendmail郵箱中

#include "readwrite.h"#include "prioq.h"#include "env.h"#include "stralloc.h"#include "subfd.h"#include "substdio.h"#include "getln.h"#include "error.h"#include "open.h"#include "lock.h"#include "gfrom.h"#include "str.h"#include "exit.h"#include "myctime.h"#include "maildir.h"char *mbox;char *mboxtmp;stralloc filenames = {0};prioq pq = {0};prioq pq2 = {0};stralloc line = {0};stralloc ufline = {0};char inbuf[SUBSTDIO_INSIZE];char outbuf[SUBSTDIO_OUTSIZE];#define FATAL "maildir2mbox: fatal: "#define WARNING "maildir2mbox: warning: "void die_nomem() { strerr_die2x(111,FATAL,"out of memory"); }void main(){ substdio ssin; substdio ssout; struct prioq_elt pe; int fdoldmbox; int fdnewmbox; int fd; int match; int fdlock; umask(077); mbox = env_get("MAIL"); if (!mbox) strerr_die2x(111,FATAL,"MAIL not set"); mboxtmp = env_get("MAILTMP"); if (!mboxtmp) strerr_die2x(111,FATAL,"MAILTMP not set"); if (maildir_chdir() == -1)   strerr_die1(111,FATAL,&maildir_chdir_err); maildir_clean(&filenames); if (maildir_scan(&pq,&filenames,1,1) == -1)   strerr_die1(111,FATAL,&maildir_scan_err); if (!prioq_min(&pq,&pe)) _exit(0); /* nothing new */ fdlock = open_append(mbox); if (fdlock == -1)   strerr_die4sys(111,FATAL,"unable to lock ",mbox,": "); if (lock_ex(fdlock) == -1)   strerr_die4sys(111,FATAL,"unable to lock ",mbox,": "); fdoldmbox = open_read(mbox); if (fdoldmbox == -1)   strerr_die4sys(111,FATAL,"unable to read ",mbox,": "); fdnewmbox = open_trunc(mboxtmp); if (fdnewmbox == -1)   strerr_die4sys(111,FATAL,"unable to create ",mboxtmp,": "); substdio_fdbuf(&ssin,read,fdoldmbox,inbuf,sizeof(inbuf)); substdio_fdbuf(&ssout,write,fdnewmbox,outbuf,sizeof(outbuf)); switch(substdio_copy(&ssout,&ssin))  {   case -2: strerr_die4sys(111,FATAL,"unable to read ",mbox,": ");   case -3: strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");  } while (prioq_min(&pq,&pe))  {   prioq_delmin(&pq);   if (!prioq_insert(&pq2,&pe)) die_nomem();   fd = open_read(filenames.s + pe.id);   if (fd == -1)     strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");   substdio_fdbuf(&ssin,read,fd,inbuf,sizeof(inbuf));   if (getln(&ssin,&line,&match,'\n') != 0)     strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");      if (!stralloc_copys(&ufline,"From XXX ")) die_nomem();   if (match)     if (stralloc_starts(&line,"Return-Path: <"))      {       if (line.s[14] == '>')	{         if (!stralloc_copys(&ufline,"From MAILER-DAEMON ")) die_nomem();	}       else	{	 int i;         if (!stralloc_ready(&ufline,line.len)) die_nomem();         if (!stralloc_copys(&ufline,"From ")) die_nomem();	 for (i = 14;i < line.len - 2;++i)	   if ((line.s[i] == ' ') || (line.s[i] == '\t'))	     ufline.s[ufline.len++] = '-';	   else	     ufline.s[ufline.len++] = line.s[i];         if (!stralloc_cats(&ufline," ")) die_nomem();	}      }   if (!stralloc_cats(&ufline,myctime(pe.dt))) die_nomem();   if (substdio_put(&ssout,ufline.s,ufline.len) == -1)     strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");   while (match && line.len)    {     if (gfrom(line.s,line.len))       if (substdio_puts(&ssout,">") == -1)         strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");     if (substdio_put(&ssout,line.s,line.len) == -1)       strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");     if (!match)      {       if (substdio_puts(&ssout,"\n") == -1)         strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");       break;      }     if (getln(&ssin,&line,&match,'\n') != 0)       strerr_die4sys(111,FATAL,"unable to read $MAILDIR/",filenames.s + pe.id,": ");    }   if (substdio_puts(&ssout,"\n"))     strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": ");   close(fd);  } if (substdio_flush(&ssout) == -1)   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": "); if (fsync(fdnewmbox) == -1)   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": "); if (close(fdnewmbox) == -1) /* NFS dorks */   strerr_die4sys(111,FATAL,"unable to write to ",mboxtmp,": "); if (rename(mboxtmp,mbox) == -1)   strerr_die6(111,FATAL,"unable to move ",mboxtmp," to ",mbox,": ",&strerr_sys);  while (prioq_min(&pq2,&pe))  {   prioq_delmin(&pq2);   if (unlink(filenames.s + pe.id) == -1)     strerr_warn4(WARNING,"$MAILDIR/",filenames.s + pe.id," will be delivered twice; unable to unlink: ",&strerr_sys);  } _exit(0);}