Incompatible with Pidgin <2.11

[giordy]

Hello,

I proceeded as follows:

1. installed the packages: libpurple-dev libjson-glib-dev libglib2.0-dev libhttp-parser-dev gcc
2. the compilation was failing and I removed -Werror from Makefile.common
3. make && sudo make install
4. started Pidgin but the Matrix protocol is not listed

I checked and libmatrix.so was created and correctly placed in /usr/lib/purple-2

[richvdh]

@penguin42: presumably this is the problem with ubuntu's old libpurple as per https://bugs.launchpad.net/bugs/1620683?

[giordy]

Ubuntu 16.04 is using Pidgin 2.10.12.

This is the changelog of Pidgin 2.11: https://bitbucket.org/pidgin/www/src/tip/htdocs/ChangeLog?fileviewer=file-view-default

Unfortunately I have almost 0 experience with C/C++ and I don't know if the changes between 2.10.12 and 2.11 could be the reason of the malfunctioning plugin.

What I can tell you is this:

• I compiled the plugin in Fedora 24 (the distro I'm using) that features pidgin 2.11 and I faced no compilation error and the plugin works correctly
• When I helped a friend compiling the plugin in Ubuntu 16.04, compilation failed (I had to remove -Werror) and pidgin failed to load the plugin.

[richvdh]

Can you confirm the error you saw when compiling on 16.04?

(also if you run pidgin with -d it will give you a debug log which may give hints as to why it won't load; but I suspect that removing -Werror has done little except let you build a broken plugin)

[giordy]

After cloning the repository and running make this is the error that I get:

$ make
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -Werror -DPURPLE_PLUGINS  -MMD  -c -o libmatrix.o libmatrix.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -Werror -DPURPLE_PLUGINS  -MMD  -c -o matrix-api.o matrix-api.c
matrix-api.c: In function ‘matrix_api_start_full’:
matrix-api.c:502:19: error: implicit declaration of function ‘purple_util_fetch_url_request_data_len_with_account’ [-Werror=implicit-function-declaration]
     purple_data = purple_util_fetch_url_request_data_len_with_account(
                   ^
matrix-api.c:502:17: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
     purple_data = purple_util_fetch_url_request_data_len_with_account(
                 ^
cc1: all warnings being treated as errors
Makefile.common:35: set di istruzioni per l'obiettivo "matrix-api.o" non riuscito
make: *** [matrix-api.o] Errore 1

The version of GCC is: gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.2)

If I remove -Werror this is the output:

$ make
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-api.o matrix-api.c
matrix-api.c: In function ‘matrix_api_start_full’:
matrix-api.c:502:19: warning: implicit declaration of function ‘purple_util_fetch_url_request_data_len_with_account’ [-Wimplicit-function-declaration]
     purple_data = purple_util_fetch_url_request_data_len_with_account(
                   ^
matrix-api.c:502:17: warning: assignment makes pointer from integer without a cast [-Wint-conversion]
     purple_data = purple_util_fetch_url_request_data_len_with_account(
                 ^
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-connection.o matrix-connection.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-event.o matrix-event.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-json.o matrix-json.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-room.o matrix-room.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-roommembers.o matrix-roommembers.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-statetable.o matrix-statetable.c
gcc -pthread -I/usr/include/libpurple -I/usr/include/json-glib-1.0 -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -fPIC -DPIC -Wall -g -O0 -DPURPLE_PLUGINS  -MMD  -c -o matrix-sync.o matrix-sync.c
gcc   -shared libmatrix.o matrix-api.o matrix-connection.o matrix-event.o matrix-json.o matrix-room.o matrix-roommembers.o matrix-statetable.o matrix-sync.o  -lpurple -ljson-glib-1.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lhttp_parser -o libmatrix.so

Then sudo make install:

$ sudo make install 
[sudo] password di novadart: 
mkdir -p /usr/lib/purple-2
install -m 664 libmatrix.so /usr/lib/purple-2
for i in 16 22 48; do \
    mkdir -p /usr/share/pixmaps/pidgin/protocols/$i; \
    install -m 664 matrix-${i}px.png /usr/share/pixmaps/pidgin/protocols/$i/matrix.png; \
done

The I ran pidgin with the -d option and found these lines in the output:

(12:01:58) plugins: probing /usr/lib/purple-2/libmatrix.so
(12:01:58) plugins: /usr/lib/purple-2/libmatrix.so is not loadable: undefined symbol: purple_util_fetch_
url_request_data_len_with_account
(12:01:58) matrixprpl: starting up
(12:01:58) plugins: probing /usr/lib/purple-2/newline.so
(12:01:58) plugins: probing /usr/lib/purple-2/buddynote.so
(12:01:58) plugins: probing /usr/lib/purple-2/ssl-nss.so
(12:01:58) util: Reading file xmpp-caps.xml from directory /home/novadart/.purple
(12:01:58) util: File /home/novadart/.purple/xmpp-caps.xml does not exist (this is not necessarily an er
ror)
(12:01:58) jabber: creating hash tables for data objects
(12:01:58) gg: Loading Gadu-Gadu protocol plugin with libgadu 1.12.1...
(12:01:58) matrixprpl: shutting down

Let me know if you needed further info.

[richvdh]

Right; so it is indeed the incompatibility with pidgin 2.10. Removing -Werror won't help fix the problem.

We'll either need to persuade Ubuntu to update their version of Pidgin, or work around it.

Or you could install pidgin 2.11 from source.

[giordy]

Ok, makes sense.
Thanks for the feedback :)

[penguin42]

Hi @giordy,
I've just created a pull request for a workaround, see
e32948f

that seems to work on my ubuntu 16.10 box and I think it should work on 16.04 as well. Sorry but it wont let you upload images though.

[giordy]

@penguin42 thanks a lot, I confirm that it works on Ubuntu 16.04 :)

[richvdh]

resolved via #17