Re: Build versionless .so for Android
What I try to do is packaging an app with androiddeployqt which fails with an error: The bundled library lib/libpq.so.5 doesn't end with .so. Android only supports versionless libraries ending with the .so suffix. This error was introduced in response to this issue which contains hints about the underlying problem: https://bugreports.qt.io/plugins/servlet/mobile#issue/QTBUG-101346 I hope this sheds some light Matthias On Fri, Jan 5, 2024, 21:57 Peter Eisentraut wrote: > On 05.01.24 01:00, Matthias Kuhn wrote: > > Attached a patch with a (hopefully) better wording of the comment. > > > > I have unsuccessfully tried to find an official source for this policy. > > So for reference some discussions about the topic: > > > > - > > > https://stackoverflow.com/questions/11491065/linking-with-versioned-shared-library-in-android-ndk > < > https://stackoverflow.com/questions/11491065/linking-with-versioned-shared-library-in-android-ndk > > > > - > > > https://stackoverflow.com/questions/18681401/how-can-i-remove-all-versioning-information-from-shared-object-files > < > https://stackoverflow.com/questions/18681401/how-can-i-remove-all-versioning-information-from-shared-object-files > > > What I would like to see is a specific thing that you are trying to do > that doesn't work. Probably, you are writing a program that is meant to > run on Android, and you are linking it (provide command line), and then > what happens? The linking fails? It fails to run? What is the error? > Can you provide a minimal example? And so on. > >
Re: Build versionless .so for Android
Hi On Thu, Jan 18, 2024 at 9:27 AM Peter Eisentraut wrote: > On 14.01.24 12:37, Matthias Kuhn wrote: > > What I try to do is packaging an app with androiddeployqt which fails > > with an error: > > > > The bundled library lib/libpq.so.5 doesn't end with .so. Android only > > supports versionless libraries ending with the .so suffix. > > > > This error was introduced in response to this issue which contains hints > > about the underlying problem: > > > > https://bugreports.qt.io/plugins/servlet/mobile#issue/QTBUG-101346 > > <https://bugreports.qt.io/plugins/servlet/mobile#issue/QTBUG-101346> > > I think the scenario there is using dlopen(), possibly via Qt, possibly > via Java, so it's a very specific scenario, not necessarily indicative > of a general requirement on Android, and apparently not using build-time > linking. It's quite conceivable that this issue would also exist with > Qt on other platforms. > > I haven't experienced this issue with Qt on any other platform (and I build and run the same stack on windows, linux, macos and ios). Also the links posted earlier in this thread hint to the same limitation of Android, unrelated to Qt. > As I mentioned before, Meson has Android support. Some people there > clearly thought about it. So I suggest you try building PostgreSQL for > your Android environment using Meson and see what it produces.(*) If > the output files are the same as the autoconf/make build, then I would > think your scenario is nonstandard. If the output files are different, > then we should check that and consider changes to get them to match. > > It's of course possible that Meson is wrong, too, but then we need to > have a broader analysis, because the implicit goal is to keep the two > build systems for PostgreSQL consistent. > When trying to build with meson, including the patch which was provided by Andres Freud (thanks), I am currently stuck with the following error: Configuring pg_config_ext.h using configuration ../src/tgresql-16-685bc9fc97.clean/src/include/meson.build:12:0: ERROR: File port/android.h does not exist. Kind regards Matthias > > (*) - This means specifically that the installation trees produced by > "make install-world-bin" and "meson install" should produce exactly the > same set of files (same names in the same directories, not necessarily > the same contents). > >
Re: Build versionless .so for Android
Thanks, This patch brought it further and indeed, the resulting libpq.so file is unversioned when built for Android while it's versioned when built for linux. Matthias On Fri, Jan 19, 2024 at 3:00 PM Peter Eisentraut wrote: > On 19.01.24 11:08, Matthias Kuhn wrote: > > When trying to build with meson, including the patch which was provided > > by Andres Freud (thanks), > > I am currently stuck with the following error: > > > > Configuring pg_config_ext.h using configuration > > > > ../src/tgresql-16-685bc9fc97.clean/src/include/meson.build:12:0: ERROR: > > File port/android.h does not exist. > > I think there is actually small bug in the meson setup. > > In the top-level meson.build, line 166 has > > portname = host_system > > but then later around line 190, host_system is changed for some cases > (including the android case that was added in the proposed patch). So > that won't work, and probably also won't work for the existing cases > there. The portname assignment needs to be moved later in the file. > Maybe you can try that on your own. > >
Build versionless .so for Android
Hi,
In order to ship libpq on Android, it needs to be built without a version
suffix on the .so file.
The attached patch will make sure that no version is added when built for
Android.
I was wondering if there are a) any comments on the approach and if I
should be handed in for a commitfest (currently waiting for the cooldown
period after account activation, I am not sure how long that is)
Thank you for any feedback
Matthias
diff --git a/src/Makefile.shlib b/src/Makefile.shlib
index 92d893e..4801b7a 100644
--- a/src/Makefile.shlib
+++ b/src/Makefile.shlib
@@ -187,7 +187,13 @@ endif
ifeq ($(PORTNAME), linux)
LINK.shared = $(COMPILER) -shared
ifdef soname
-LINK.shared += -Wl,-soname,$(soname)
+ifeq (linux-android,$(findstring linux-android,$(host_os)))
+#crosscompiling for android needs to create unvesioned libs
+shlib = lib$(NAME)$(DLSUFFIX)
+LINK.shared += -Wl,-soname,lib$(NAME)$(DLSUFFIX)
+else
+LINK.shared += -Wl,-soname,$(soname)
+endif
endif
BUILD.exports = ( echo '{ global:'; $(AWK) '/^[^\#]/ {printf "%s;\n",$$1}' $<; echo ' local: *; };' ) >$@
exports_file = $(SHLIB_EXPORTS:%.txt=%.list)
Re: Build versionless .so for Android
Thanks for all the comments and help.
I have added the patch to the January CF.
It looks like meson does not currently support building for android, the
following output is what I get (but I have actually no experience with
meson):
meson.build:320:2: ERROR: Problem encountered: unknown host system:
android
Please find an attached patch which also includes a documentation section.
I am happy to adjust if needed.
Kind regards
Matthias
diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index 75dc81a..9c88558 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -1989,6 +1989,14 @@ build-postgresql:
among developers is to use PROFILE for one-time flag
adjustments, while COPT might be kept set all the time.
+
+
+ When building libpq as shared libraries, the resulting files are suffixed
+ with the version libpq.5.[version] and an unversioned
+ symlink libpq.soto the versioned file is created. An
+ exception to that is Android where library file names must end with
+ .so. Building for Android is only supported using make.
+
diff --git a/src/Makefile.shlib b/src/Makefile.shlib
index 92d893e..4801b7a 100644
--- a/src/Makefile.shlib
+++ b/src/Makefile.shlib
@@ -187,7 +187,13 @@ endif
ifeq ($(PORTNAME), linux)
LINK.shared = $(COMPILER) -shared
ifdef soname
-LINK.shared += -Wl,-soname,$(soname)
+ifeq (linux-android,$(findstring linux-android,$(host_os)))
+#crosscompiling for android needs to create unvesioned libs
+shlib = lib$(NAME)$(DLSUFFIX)
+LINK.shared += -Wl,-soname,lib$(NAME)$(DLSUFFIX)
+else
+LINK.shared += -Wl,-soname,$(soname)
+endif
endif
BUILD.exports = ( echo '{ global:'; $(AWK) '/^[^\#]/ {printf "%s;\n",$$1}' $<; echo ' local: *; };' ) >$@
exports_file = $(SHLIB_EXPORTS:%.txt=%.list)
Re: Build versionless .so for Android
Hi,
Attached a patch with a (hopefully) better wording of the comment.
I have unsuccessfully tried to find an official source for this policy.
So for reference some discussions about the topic:
-
https://stackoverflow.com/questions/11491065/linking-with-versioned-shared-library-in-android-ndk
-
https://stackoverflow.com/questions/18681401/how-can-i-remove-all-versioning-information-from-shared-object-files
Please let me know if I can help in any way
Matthias
On Tue, Jan 2, 2024 at 6:43 PM Robert Haas wrote:
> On Sun, Dec 31, 2023 at 1:24 AM Michael Paquier
> wrote:
> > FWIW, I have mixed feelings about patching the code to treat
> > android-linux as an exception while changing nothing in the
> > documentation to explain why this is required. A custom patch may
> > serve you better here, and note that you did not even touch the meson
> > paths. See libpq_c_args in src/interfaces/libpq/meson.build as one
> > example. That's just my opinion, of course, still there are no
> > buildfarm members that would cover your patch.
>
> It's reasonable to want good comments -- the one in the patch (1)
> doesn't explain why this is required and (2) suggests that it is only
> needed when cross-compiling which seems surprising and (3) has a typo.
> But if it's true that this is needed, I tentatively think we might do
> better to take the patch than force people to carry it out of tree.
>
> --
> Robert Haas
> EDB: http://www.enterprisedb.com
>
diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index 75dc81a..9c88558 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -1989,6 +1989,14 @@ build-postgresql:
among developers is to use PROFILE for one-time flag
adjustments, while COPT might be kept set all the time.
+
+
+ When building libpq as shared libraries, the resulting files are suffixed
+ with the version libpq.5.[version] and an unversioned
+ symlink libpq.soto the versioned file is created. An
+ exception to that is Android where library file names must end with
+ .so. Building for Android is only supported using make.
+
diff --git a/src/Makefile.shlib b/src/Makefile.shlib
index 92d893e..4801b7a 100644
--- a/src/Makefile.shlib
+++ b/src/Makefile.shlib
@@ -187,7 +187,13 @@ endif
ifeq ($(PORTNAME), linux)
LINK.shared = $(COMPILER) -shared
ifdef soname
-LINK.shared += -Wl,-soname,$(soname)
+ifeq (linux-android,$(findstring linux-android,$(host_os)))
+# Android does not support versioned soname
+shlib = lib$(NAME)$(DLSUFFIX)
+LINK.shared += -Wl,-soname,lib$(NAME)$(DLSUFFIX)
+else
+LINK.shared += -Wl,-soname,$(soname)
+endif
endif
BUILD.exports = ( echo '{ global:'; $(AWK) '/^[^\#]/ {printf "%s;\n",$$1}' $<; echo ' local: *; };' ) >$@
exports_file = $(SHLIB_EXPORTS:%.txt=%.list)
