[lwip-devel] [bug #51519] Clarify that sys_arch_protect() always has a matching unprotect.

[Douglas]

URL:
  <http://savannah.nongnu.org/bugs/?51519>

                 Summary: Clarify that sys_arch_protect() always has a
matching unprotect.
                 Project: lwIP - A Lightweight TCP/IP stack
            Submitted by: ourairquality
            Submitted on: Thu 20 Jul 2017 12:34:05 PM UTC
                Category: Documentation
                Severity: 3 - Normal
              Item Group: Change Request
                  Status: None
                 Privacy: Public
             Assigned to: None
             Open/Closed: Open
         Discussion Lock: Any
         Planned Release: None
            lwIP version: git head

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Details:

The current documentation specifies sys_arch_unprotect() as resetting "the
critical region protection to the value specified by pval". Such usage would
not be compatible with implementations using a nesting counter, nor with many
recursive mutex implementations, both of which require matching protect and
unprotect operations.

Practically the current code seems to match protect and unprotect operations,
so this is basically a warning that some implementations would break if there
were not a matching unprotect for each protect operation. Also a warning that
lwip code should not use the value returned by sys_arch_unprotect() except to
pass it along.



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File Attachments:


-------------------------------------------------------
Date: Thu 20 Jul 2017 12:34:05 PM UTC  Name:
0001-Clarify-that-sys_arch_protect-always-has-a-matching-.patch  Size: 3KiB  
By: ourairquality

<http://savannah.nongnu.org/bugs/download.php?file_id=41264>

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