02-21-2010
Let me get this straight: you have a custom memory management library, and your code using that library crashes?
OK.
You need all the help you can get. But there's not much out there.
Your only hope is to do something like download a demo copy of Purify and use it. And then pray that you don't have any bugs in your custom library.
And good luck.
You're going to need it.
There's a reason why nobody writes their own memory management libraries. First off, the multiple libraries available for free on your OS of choice are almost certainly fast enough. If they're not, you're most likely doing something wrong, like an over-reliance on malloc()/free() and/or new/delete. And if the OS libaries truly aren't fast enough (and if you're not multithreaded on a massively parallel application, they ARE fast enough!), there are third-party memory management libraries available.
Go price something like Smartheap. Then calculate all the hours spent on your custom memory library and how much those hours cost. Want to bet Smartheap is cheaper? If you even need it in the first place.
There are probably literally thousands of man-years invested by many absolutely brilliant computer scientists and programmers in all the memory-management libraries available in today's operating systems. And those products have been thoroughly tested - for literally decades.
You want a car analogy? Writing your own memory management library is like chiseling out a stone wheel for a sports car. The only reason to do it is for the sake of doing it - as a hobby or academic learning experience. Because there's no way you can duplicate the engineering history behind a "normal" wheel. Even if you do manage to chisel out a wheel that manages to outperform a "normal" wheel in a tiny operating range, you'll never really know how durable your wheel is because it's totally untested.
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LEARN ABOUT LINUX
pam_wheel
PAM_WHEEL(8) Linux-PAM Manual PAM_WHEEL(8)
NAME
pam_wheel - Only permit root access to members of group wheel
SYNOPSIS
pam_wheel.so [debug] [deny] [group=name] [root_only] [trust]
DESCRIPTION
The pam_wheel PAM module is used to enforce the so-called wheel group. By default it permits root access to the system if the applicant
user is a member of the wheel group. If no group with this name exist, the module is using the group with the group-ID 0.
OPTIONS
debug
Print debug information.
deny
Reverse the sense of the auth operation: if the user is trying to get UID 0 access and is a member of the wheel group (or the group of
the group option), deny access. Conversely, if the user is not in the group, return PAM_IGNORE (unless trust was also specified, in
which case we return PAM_SUCCESS).
group=name
Instead of checking the wheel or GID 0 groups, use the name group to perform the authentication.
root_only
The check for wheel membership is done only.
trust
The pam_wheel module will return PAM_SUCCESS instead of PAM_IGNORE if the user is a member of the wheel group (thus with a little play
stacking the modules the wheel members may be able to su to root without being prompted for a passwd).
MODULE TYPES PROVIDED
The auth and account module types are provided.
RETURN VALUES
PAM_AUTH_ERR
Authentication failure.
PAM_BUF_ERR
Memory buffer error.
PAM_IGNORE
The return value should be ignored by PAM dispatch.
PAM_PERM_DENY
Permission denied.
PAM_SERVICE_ERR
Cannot determine the user name.
PAM_SUCCESS
Success.
PAM_USER_UNKNOWN
User not known.
EXAMPLES
The root account gains access by default (rootok), only wheel members can become root (wheel) but Unix authenticate non-root applicants.
su auth sufficient pam_rootok.so
su auth required pam_wheel.so
su auth required pam_unix.so
SEE ALSO
pam.conf(5), pam.d(5), pam(7)
AUTHOR
pam_wheel was written by Cristian Gafton <gafton@redhat.com>.
Linux-PAM Manual 05/31/2011 PAM_WHEEL(8)