#include "fd.h"#include "stralloc.h"#include "readwrite.h"#include "sgetopt.h"#include "wait.h"#include "env.h"#include "byte.h"#include "str.h"#include "alloc.h"#include "exit.h"#include "fork.h"#include "case.h"#include "subfd.h"#include "error.h"#include "substdio.h"#include "sig.h"void die(e,s) int e; char *s; { substdio_putsflush(subfderr,s); _exit(e); }void die_usage() { die(100,"qsmhook: fatal: incorrect usage\n"); }void die_temp() { die(111,"qsmhook: fatal: temporary problem\n"); }void die_read() { die(111,"qsmhook: fatal: unable to read message\n"); }void die_badcmd() { die(100,"qsmhook: fatal: command not found\n"); }int flagrpline = 0; char *rpline;int flagufline = 1; char *ufline;int flagdtline = 0; char *dtline;char *host;char *sender;char *recip;stralloc newarg = {0};substdio ssout;char outbuf[SUBSTDIO_OUTSIZE];substdio ssin;char inbuf[SUBSTDIO_INSIZE];void main(argc,argv)int argc;char **argv;{ int pid; int wstat; int pi[2]; int opt; char **arg; char *x; int i; int flagesc; sig_pipeignore(); if (!(dtline = env_get("DTLINE"))) die_usage(); if (!(rpline = env_get("RPLINE"))) die_usage(); if (!(ufline = env_get("UFLINE"))) die_usage(); if (!(recip = env_get("LOCAL"))) die_usage(); if (!(host = env_get("HOST"))) die_usage(); if (!(sender = env_get("SENDER"))) die_usage(); while ((opt = getopt(argc,argv,"DFlMmnPsx:")) != opteof)   switch(opt)    {     case 'D': case 'F': case 'M': break; /* be serious */     case 'l': flagdtline = 1; break; /* also return-receipt-to? blech */     case 'm': break; /* we only handle one recipient anyway */     case 'n': flagufline = 0; break;     case 's': break; /* could call quote() otherwise, i suppose... */     case 'P': flagrpline = 1; break;     case 'x':       if (case_starts(recip,optarg))	 recip += str_len(optarg);       break;     default:       _exit(100);    } argc -= optind; argv += optind; if (!*argv) die_usage(); for (arg = argv;x = *arg;++arg)  {   if (!stralloc_copys(&newarg,"")) die_temp();   flagesc = 0;   for (i = 0;x[i];++i)     if (flagesc)      {       switch(x[i])	{	 case '%': if (!stralloc_cats(&newarg,"%")) die_temp(); break;	 case 'g': if (!stralloc_cats(&newarg,sender)) die_temp(); break;	 case 'h': if (!stralloc_cats(&newarg,host)) die_temp(); break;	 case 'u': if (!stralloc_cats(&newarg,recip)) die_temp(); break;	}       flagesc = 0;      }     else       if (x[i] == '%')	 flagesc = 1;       else	 if (!stralloc_append(&newarg,&x[i])) die_temp();   if (!stralloc_0(&newarg)) die_temp();   i = str_len(newarg.s) + 1;   if (!(x = alloc(i))) die_temp();   byte_copy(x,i,newarg.s);   *arg = x;  } if (pipe(pi) == -1) die_temp(); switch(pid = fork())  {   case -1:     die_temp();   case 0:     close(pi[1]);     if (fd_move(0,pi[0]) == -1) die_temp();     sig_pipedefault();     execvp(*argv,argv);     if (error_temp(errno)) die_temp();     die_badcmd();  } close(pi[0]); substdio_fdbuf(&ssout,write,pi[1],outbuf,sizeof(outbuf)); substdio_fdbuf(&ssin,read,0,inbuf,sizeof(inbuf)); if (flagufline) substdio_bputs(&ssout,ufline); if (flagrpline) substdio_bputs(&ssout,rpline); if (flagdtline) substdio_bputs(&ssout,dtline); if (substdio_copy(&ssout,&ssin) == -2) die_read(); substdio_flush(&ssout); close(pi[1]); if (wait_pid(&wstat,pid) == -1) die_temp(); if (wait_crashed(wstat)) die_temp(); _exit(wait_exitcode(wstat));}