RFR(XS):8244248: boot-jdk.m4 captures the version line using regex

Erik Joelsson erik.joelsson at oracle.com
Fri May 1 21:13:40 UTC 2020 

On 2020-05-01 13:44, Liu, Xin wrote:
> Hello, Erik,
>
> Thank you for your comments.  I made some change. Could you review it again?
> JBS: https://bugs.openjdk.java.net/browse/JDK-8244248
> Webrev: https://cr.openjdk.java.net/~xliu/8244248/00/webrev/
This looks good.
> Some new comments:
> 1) I don't know that there're subtle difference between '-version' and '--version'.  This patch only captures '-version'.
> Thanks to point out that LAUNCH_NAME is configurable. I think your regex is better.
>
> 2) From my personal experience, I feel awk regex is more portable than grep.
> The reason that '[' and ']' look so strange because it's m4 file. I can't find an effective way to escape them but quadrigrpahs.
> https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Quadrigraphs.html#Quadrigraphs

You can escape with more [] as long as they are balanced, which they are 
here. I think it's generally more readable if you enclose a whole 
expression, like the whole awk script, inside [] rather than just 
doubling them up inside the regexp. You can see examples of how we use 
this in jdk-version.m4.

> Testing:
> I use the awk around different jdks.
> i) oraclejdk
> ~  /Library/Java/JavaVirtualMachines/jdk-14.0.1.jdk/Contents/Home/bin/java -version 2>&1 | awk '/version \"[0-9\._\-a-zA-Z]+\"/{print $0;exit;}'
> java version "14.0.1" 2020-04-14
> i) openjdk
> ./build/linux-x86_64-server-fastdebug/jdk/bin/java -version 2>&1  | awk '/version \"[0-9\._\-a-zA-Z]+\"/{print $0;exit;}'
> openjdk version "15-internal" 2020-09-15
> i) zulu
> docker run -it --rm azul/zulu-openjdk:latest java -version  |& awk '/version \"[0-9\._\-a-zA-Z]+\"/{print $0;exit;}'
> openjdk version "1.8.0_242"

I tried this and it seems to work for me too.

/Erik

> thanks,
> --lx
>
>
> On 5/1/20, 6:06 AM, "Erik Joelsson" <erik.joelsson at oracle.com> wrote:
>
>      CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>
>
>
>      Hello,
>
>      My OracleJDK 14 displays:
>
>      java version "14" 2020-03-17
>
>      Not sure where you found a version output without the word "version" in it.
>
>       From what I understand, any distributor is free to change the "openjdk"
>      prefix of this line, so relying on there only being 2 cases is not a
>      good idea. If we assume the boot jdk must be an OpenJDK derivative, then
>      a regular expression that tries to capture the line in more detail would
>      be preferred. The aspects I would try to capture would be the word
>      version and a bunch of numbers and dots (and possibly underscore if we
>      want to keep it compatible with even older java versions for easier
>      backports) inside double quotes. Something like this perhaps:
>
>      grep "version \"[0-9\._]*\""
>
>      I tried that expression manually on Mac, Linux and Solaris so should be
>      portable enough.
>
>      /Erik
>
>      On 2020-04-30 16:48, Liu, Xin wrote:
>      > Hi, Andrew,
>      >
>      > How about this?  I can use awk to capture java -version.  There're 2 cases.
>      >
>      > I) openjdk
>      > openjdk version "14.0.1" 2020-04-14
>      > 2) oraclejdk
>      > java 14.0.1 2020-04-14
>      >
>      > if somehow java displays some error/warning messages,  awk can filter them out and capture the version line.
>      > Eg.
>      > $ ~/builds/jdk-14.0.1+7/bin/java -version
>      > [0.009s][error][cds] Unable to map CDS archive -- os::vm_allocation_granularity() expected: 65536 actual: 4096
>      > openjdk version "14.0.1" 2020-04-14
>      > OpenJDK Runtime Environment AdoptOpenJDK (build 14.0.1+7)
>      > OpenJDK 64-Bit Server VM AdoptOpenJDK (build 14.0.1+7, mixed mode)
>      > $ ~/builds/jdk-14.0.1+7/bin/java -version 2>&1 | awk '/^(openjdk version|java)/ {print $0}'
>      > openjdk version "14.0.1" 2020-04-14
>      >
>      > I think this awk stmt is portable, but it's always good to ask experts to review it, so I cc build-dev.
>      >
>      > Hers is the change.
>      >
>      > diff --git a/make/autoconf/boot-jdk.m4 b/make/autoconf/boot-jdk.m4
>      > --- a/make/autoconf/boot-jdk.m4
>      > +++ b/make/autoconf/boot-jdk.m4
>      > @@ -74,7 +74,7 @@
>      >             BOOT_JDK_FOUND=no
>      >           else
>      >             # Oh, this is looking good! We probably have found a proper JDK. Is it the correct version?
>      > -          BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java$EXE_SUFFIX" $USER_BOOT_JDK_OPTIONS -version 2>&1 | $HEAD -n 1`
>      > +          BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java$EXE_SUFFIX" $USER_BOOT_JDK_OPTIONS -version 2>&1 | $AWK '/^(openjdk version|java)/ {print [$]0}'`
>      >             if [ [[ "$BOOT_JDK_VERSION" =~ "Picked up" ]] ]; then
>      >               AC_MSG_NOTICE([You have _JAVA_OPTIONS or JAVA_TOOL_OPTIONS set. This can mess up the build. Please use --with-boot-jdk-jvmargs instead.])
>      >               AC_MSG_NOTICE([Java reports: "$BOOT_JDK_VERSION".])
>      > @@ -529,7 +529,7 @@
>      >           BUILD_JDK_FOUND=no
>      >         else
>      >           # Oh, this is looking good! We probably have found a proper JDK. Is it the correct version?
>      > -        BUILD_JDK_VERSION=`"$BUILD_JDK/bin/java" -version 2>&1 | $HEAD -n 1`
>      > +        BUILD_JDK_VERSION=`"$BUILD_JDK/bin/java" -version 2>&1 | $AWK '/^(openjdk version|java)/ {print [$]0}'`
>      >
>      >           # Extra M4 quote needed to protect [] in grep expression.
>      >           [FOUND_CORRECT_VERSION=`echo $BUILD_JDK_VERSION | $EGREP "\"$VERSION_FEATURE([\.+-].*)?\""`]
>      >
>      >
>      >
>      > On 4/30/20, 2:52 PM, "aarch64-port-dev on behalf of Liu, Xin" <aarch64-port-dev-bounces at openjdk.java.net on behalf of xxinliu at amazon.com> wrote:
>      >
>      >      Hi, Andrew,
>      >
>      >      That's a hack. A general way should use grep or sed to capture the needed line instead of hardcoding first or second line.
>      >      Okay, Let me try to do that.
>      >
>      >      Thanks,
>      >      --lx
>      >
>      >
>      >      On 4/30/20, 1:19 AM, "aph at redhat.com" <aph at redhat.com> wrote:
>      >
>      >          CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe.
>      >
>      >
>      >
>      >          On 4/30/20 12:43 AM, Liu, Xin wrote:
>      >          > One trick here. It's very easy to cheat configure by hacking the boot-jdk.m4 to "$HEAD -n 2". Everything looks fine then.
>      >
>      >          The fix should be submitted to build-dev.
>      >
>      >          --
>      >          Andrew Haley  (he/him)
>      >          Java Platform Lead Engineer
>      >          Red Hat UK Ltd. <https://www.redhat.com>
>      >          https://keybase.io/andrewhaley
>      >          EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671
>      >
>      >
>      >
>

More information about the build-dev mailing list