/*

 * lftp - file transfer program

 *

 * Copyright (c) 1996-2017 by Alexander V. Lukyanov (lav@yars.free.net)

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#include <config.h>

#include <stdarg.h>

#include <fcntl.h>

#include <sys/types.h>

#include <sys/stat.h>

#include "xstring.h"

#include "log.h"

#include "SMTask.h"

Ref<Log> Log::global;

static ResType log_vars[] = {

   {"log:enabled",   "no", ResMgr::BoolValidate},

   {"log:level",     "9",  ResMgr::UNumberValidate},

   {"log:show-time", "no", ResMgr::BoolValidate},

   {"log:show-pid",  "no", ResMgr::BoolValidate},

   {"log:show-ctx",  "no", ResMgr::BoolValidate},

   {"log:file",	     "",   ResMgr::FileCreatable},

   {"log:max-size",  "1M", ResMgr::UNumberValidate},

   {"log:prefix-recv","<--- "},

   {"log:prefix-send","---> "},

   {"log:prefix-note","---- "},

   {"log:prefix-error","**** "},

   {0}

};

static ResDecls log_vars_register(log_vars);

Log::Log(const char *name)

   : name(name)

{

   output=-1;

   need_close_output=false;

   tty_cb=0;

   enabled=false;

   level=0;

   tty=false;

   show_pid=true;

   show_time=true;

   show_context=true;

   at_line_start=true;

   Reconfig(0);

}

bool Log::WillOutput(int l)

{

   if(!enabled || l>level || output==-1)

      return false;

   if(tty)

   {

      pid_t pg=tcgetpgrp(output);

      if(pg!=(pid_t)-1 && pg!=getpgrp())

	 return false;

   }

   return true;

}

void Log::Write(int l,const char *s,int len)

{

   if(!WillOutput(l))

      return;

   DoWrite(s,len);

}

void Log::DoWrite(const char *s,int len)

{

   if(len==0)

      return;

   if(buf.length()==0 || buf.last_char()=='\n') {

      if(show_pid)

	 buf.appendf("[%ld] ",(long)getpid());

      if(show_time)

	 buf.append(SMTask::now.IsoDateTime()).append(' ');

      if(show_context)

      {

	 const char *ctx=SMTask::GetCurrentLogContext();

	 if(ctx)

	    buf.append(ctx).append(' ');

      }

   }

   buf.append(s,len);

   if(buf.last_char()!='\n')

      return;

   if(tty_cb && tty)

      tty_cb();

   int res=write(output,buf,buf.length());

   if(res==-1) {

      if(E_RETRY(errno))

	 return;

      ResMgr::Set("log:enabled",name,"no");

      return;

   }

   if(res==(int)buf.length())

      buf.truncate();

   else

      buf.set_substr(0,res,"",0);

}

void Log::Format(int l,const char *f,...)

{

   if(!WillOutput(l))

      return;

   va_list v;

   va_start(v,f);

   DoWrite(xstring::vformat(f,v));

   va_end(v);

}

void Log::vFormat(int l,const char *f,va_list v)

{

   if(!WillOutput(l))

      return;

   DoWrite(xstring::vformat(f,v));

}

void Log::Cleanup()

{

   global=0;

}

Log::~Log()

{

   CloseOutput();

}

void Log::SetOutput(int o,bool need_close)

{

   CloseOutput();

   output=o;

   need_close_output=need_close;

   if(output!=-1)

      tty=isatty(output);

}

void Log::Reconfig(const char *n) {

   enabled=QueryBool("log:enabled");

   level=Query("log:level");

   show_time=QueryBool("log:show-time");

   show_pid=QueryBool("log:show-pid");

   show_context=QueryBool("log:show-ctx");

   if(!n || !strcmp(n,"log:file")) {

      const char *file=Query("log:file");

      int fd=2;

      bool need_close_fd=false;

      if(file && *file) {

	 struct stat st;

	 if(stat(file,&st)!=-1) {

	    if(st.st_size > long(Query("log:max-size"))) {

	       debug((9,"rotating log %s\n",file));

	       if(rename(file,xstring::cat(file,".old",NULL))==-1)

		  debug((1,"rename(%s): %s\n",file,strerror(errno)));

	    }

	 }

	 fd=open(file,O_WRONLY|O_CREAT|O_APPEND|O_NONBLOCK,0600);

	 if(fd==-1) {

	    perror(file);

	    fd=2;

	 } else {

	    need_close_fd=true;

	    fcntl(fd,F_SETFD,FD_CLOEXEC);

	 }

      }

      if(fd!=output)

	 SetOutput(fd,need_close_fd);

   }

}