kern/99826: [libc] [patch] setenv(3)/unsetenv(3) leak memory

[Sean Farley]

The following reply was made to PR kern/99826; it has been noted by GNATS.

From: Sean Farley <sean-freebsd at farley.org>
To: bug-followup at FreeBSD.org
Cc:  
Subject: Re: kern/99826: [libc] [patch] setenv(3)/unsetenv(3) leak memory
Date: Fri, 1 Jun 2007 12:11:13 -0500 (CDT)

 I have completed a new version[1] of a replacement (kern/99826[1]) for
 getenv/setenv/putenv/unsetenv().  A patch against CURRENT that updates
 libc and a few base utilities can be found here[2].  I built it and ran
 it successfully.
 
 Notes:
 1. Fixes memory leak as noted in BUGS section for setenv(3).
     Example of the leak:
     setenv("TZ", "CDT", 1);
     setenv("TZ", "YEKST", 1);  // Leaks
     setenv("TZ", "CDT", 1);
     setenv("TZ", "YEKST", 1);  // Leaks
 2. Converts all calls to POSIX from historic BSD API.
     a. unsetenv returns an int.
     b. putenv takes a char * instead of const char *.
     c. putenv no longer makes a copy of the input string.
     d. errno is set appropriately for POSIX.  Exceptions involve bad
        environ variable and internal initialization code.  These both set
        errno to EFAULT.
 3. Several patches to base utilities to handle the POSIX changes are
     from Andrey Chernov's previous commit.  A few I re-wrote to use
     setenv() instead of putenv().  Yes, I dislike putenv().  :)
 4. A new regression module to test these functions was written.  It also
     can be used to test the performance.  I found performance to be
     on-par or better.  It is found in tools/regression/environment.
 5. Man page could use more work to match all the changes.
 6. make universe successfully completed.
 
 Thank you to Andrey and others for your help in proofreading several
 iterations of the code.
 
 
 Sean
    1. http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/99826
    2. http://www.farley.org/freebsd/tmp/setenv/setenv-9/
    3. http://www.farley.org/freebsd/tmp/setenv/setenv-9/setenv.diff
 -- 
 sean-freebsd at farley.org