On Fri, 12 Jul 2024 06:29:34 GMT, Julian Waters <jwat...@openjdk.org> wrote:

> snprintf has been available for all officially and unofficially supported 
> compilers for Windows, Visual Studio since version 2015 and gcc since, well, 
> forever. snprintf is conforming to C99 since the start when compiling using 
> gcc, and 2015 when using Visual Studio. Since it conforms to C99 and provides 
> better semantics than _snprintf, and is not compiler specific, we should use 
> it in most places where we currently use _snprintf. This makes JDK code where 
> this is used more robust due to the null terminating guarantee of snprintf. 
> Since most of the changes are extremely simple, I've included all of them 
> hoping to get this all done in one shot. The only places _snprintf is not 
> replaced is places where I'm not sure whether the code is ours or not (As in, 
> imported source code for external libraries). Note that the existing checks 
> in place for the size of the characters written still work, as the return 
> value of snprintf works mostly the same as _snprintf. The only difference is 
> the nul
 l terminating character at the end and the returning of the number of written 
characters if the buffer was terminated early, as seen here: 
https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/snprintf-snprintf-snprintf-l-snwprintf-snwprintf-l?view=msvc-170
> 
> Reviews Required: 2 for HotSpot, jdk.hotspot.agent, and jdk.jdwp.agent, 1 for 
> awt and jdk.accessibility, 1 for java.base, 1 for security, 1 for 
> jdk.management(?)

This should be using `os::snprintf` rather than `snprintf`.  Rationale is in 
the comment here:
https://github.com/openjdk/jdk/blob/1f6e106b45e5109224e13d70f1a40c9e666ec2ab/src/hotspot/share/runtime/os.cpp#L118-L126

And yes, I know there are lots of bare uses of snprintf (about 125?), including 
in shared code.  That's why it isn't
currently in the forbidden list.  There's some cleanup to do there.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/20153#issuecomment-2226218368

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