🚀 go-pugleaf

Subject: getpwent(3) does not rewind in some cases (+FIX)
Index:	lib/libc/gen/getpwent.c 2.10BSD

Description:
	This only applies to the shadow/aging version of getpwent(3).

	The fetch_pw() function in getpwent.c in the
	/usr/src/lib/libc/gen/getpwent.c code checks the
	_pw_rewind flag.  If dbm_open is called
	in start_pw after having previously processed the
	entire database and then getpwent() is called, fetch_pw still 
	thinks its processing the original dbm stream.

	Setting _pw_rewind to 1 after the dbm_open fixes the
	problem, start_pw() then knows it is dealing with a
	newly dbm_opened passwd file.

Repeat-By:
	The 'filec' code in csh(1) exposed this bug.

	If you do a ~^D for login names listing, you
	can only do it once without an intervening ~username
	action.

Fix:

*** getpwent.c.old	Sat May 13 00:44:24 1989
--- getpwent.c	Tue Jul 24 21:36:32 1990
***************
*** 121,128 ****
  		rewind(_pw_fp);
  		return(1);
  	}
! 	if (_pw_db = dbm_open(_pw_file, O_RDONLY, 0))
  		return(1);
  	/*
  	 * special case; if it's the official password file, look in
  	 * the master password file, otherwise, look in the file itself.
--- 121,130 ----
  		rewind(_pw_fp);
  		return(1);
  	}
! 	if (_pw_db = dbm_open(_pw_file, O_RDONLY, 0)) {
! 		_pw_rewind = 1;
  		return(1);
+ 	}
  	/*
  	 * special case; if it's the official password file, look in
  	 * the master password file, otherwise, look in the file itself.