[12] (AIX) 8207744: Clean up inconsistent use of opendir/closedir versus opendir64/closedir64

[B. Blaser]

I checked Linux [1], Solaris [2], MacOS [3], FreeBSD [4] and AIX [5]
docs and I tried to summarize 64-bit directory usage as follows:
* [1] & [2] seem to use 'opendir/closedir/DIR' in conjunction with 'readdir64'
* [3] seems to be based on [4] which doesn't provide any specific
64-bit interface for directory usage
* [5] seems to require 'opendir64/closedir64/DIR64' to use 'readdir64'

Then, I found the following 'readdir64' usages in the JDK:

$ find ./src/ -type f -print | xargs grep "readdir64"
./src/java.base/unix/native/libnio/fs/UnixNativeDispatcher.c:#define
readdir64 readdir
./src/java.base/unix/native/libnio/fs/UnixNativeDispatcher.c:    ptr =
readdir64(dirp);
./src/java.base/unix/native/libjava/TimeZone_md.c:#define readdir64 readdir
./src/java.base/unix/native/libjava/TimeZone_md.c:    while ((dp =
readdir64(dirp)) != NULL) {
./src/java.base/unix/native/libjava/childproc.c:  #define readdir64 readdir
./src/java.base/unix/native/libjava/childproc.c:    /* We use
readdir64 instead of readdir to work around Solaris bug
./src/java.base/unix/native/libjava/childproc.c:    while ((dirp =
readdir64(dp)) != NULL) {
./src/java.base/unix/native/libjava/UnixFileSystem_md.c:  #define
readdir64 readdir
./src/java.base/unix/native/libjava/UnixFileSystem_md.c:    while
((ptr = readdir64(dir)) != NULL) {
./src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c:
 #define readdir64 readdir
./src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c:
   while ((dentp = readdir64(dirp)) != NULL) {

In these files, only 'TimeZone_md.c' & 'OperatingSystemImpl.c' seem to
be missing '#define opendir opendir64' (etc...) for AIX.

So, I guess I would do (blindly) something more like the patch below.

Do we agree?
Bernard


[1] https://www.gnu.org/software/libc/manual/html_node/Reading_002fClosing-Directory.html
[2] https://docs.oracle.com/cd/E36784_01/html/E36883/lf64-5.html
[3] https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/OSX_Technology_Overview/SystemTechnology/SystemTechnology.html
[4] https://www.freebsd.org/cgi/man.cgi?query=opendir&sektion=3
[5] https://www.ibm.com/support/knowledgecenter/en/ssw_aix_71/com.ibm.aix.basetrf1/opendir.htm


diff -r b0fcf59be391 src/java.base/unix/native/libjava/TimeZone_md.c
--- a/src/java.base/unix/native/libjava/TimeZone_md.c   Fri Jul 20
14:48:41 2018 -0700
+++ b/src/java.base/unix/native/libjava/TimeZone_md.c   Sat Jul 28
15:24:10 2018 +0200
@@ -55,6 +55,12 @@
 #define readdir64 readdir
 #endif

+#if defined(_AIX)
+  #define DIR DIR64
+  #define opendir opendir64
+  #define closedir closedir64
+#endif
+
 #if !defined(__solaris__) || defined(__sparcv9) || defined(amd64)
 #define fileopen        fopen
 #define filegets        fgets
diff -r b0fcf59be391
src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c
--- a/src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c
   Fri Jul 20 14:48:41 2018 -0700
+++ b/src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c
   Sat Jul 28 15:24:10 2018 +0200
@@ -79,6 +79,12 @@
   #define readdir64 readdir
 #endif

+#if defined(_AIX)
+  #define DIR DIR64
+  #define opendir opendir64
+  #define closedir closedir64
+#endif
+
 // true = get available swap in bytes
 // false = get total swap in bytes
 static jlong get_total_or_available_swap_space_size(JNIEnv* env,
jboolean available) {


On 27 July 2018 at 22:09, Brian Burkhalter <brian.burkhalter at oracle.com> wrote:
> Hi Bernard,
>
> I think you are correct. Webrev updated accordingly:
>
> http://cr.openjdk.java.net/~bpb/8207744/webrev.01/
>
> I know you cannot do it, but a build of this on AIX by someone would be
> appreciated (not urgent).
>
> Thanks,
>
> Brian
>
> On Jul 27, 2018, at 7:16 AM, B. Blaser <bsrbnd at gmail.com> wrote:
>
> I cannot experiment on AIX myself but as mentioned in [1], shouldn't
> this also/only be necessary in 'OperatingSystemImpl.c' &
> 'TimeZone_md.c'?
> I guess the problem on AIX is that 'readdir64' needs
> 'openddir64/closedir64/DIR64' while these methods don't exist and are
> de-facto not necessary on Linux (at least with glibc 2.26 64-bit).
> The other files you suggest to fix seem to use 'readdir' so I believe
> 'opendir/closedir' are well deserved here.
>
> What do you think?
>
> Thanks,
> Bernard
>
>
> [1]
> http://mail.openjdk.java.net/pipermail/core-libs-dev/2018-July/054439.html
>
>