[GTK4] Selecting a file using "Open File" crashes Eclipse with SIGSEV

[joel-majano]

Describe the bug
Upon selecting a file using the file dialog from "Open File" the IDE crashes.

To Reproduce
In GTK4 press "Open File" then select a text file (.txt or .c or .java, etc.) then press "Open". Eclipse will crash after pressing open.

Expected behavior
The file opens in the editor.

Screenshots

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007fb47d48ad40, pid=161827, tid=161834
#
# JRE version: OpenJDK Runtime Environment 21.9 (17.0.3+7) (build 17.0.3+7)
# Java VM: OpenJDK 64-Bit Server VM 21.9 (17.0.3+7, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# C  [libglib-2.0.so.0+0x6dd40]  g_slist_length+0x10
#
# Core dump will be written. Default location: Core dumps may be processed with "/usr/lib/systemd/systemd-coredump %P %u %g %s %t %c %h" (or dumping to /home/jmajano/EclipseBuilds/eclipse-SDK-4.23/eclipse/core.161827)
#
# An error report file with more information is saved as:
# /home/jmajano/EclipseBuilds/eclipse-SDK-4.23/eclipse/hs_err_pid161827.log
#
# If you would like to submit a bug report, please visit:
#   https://bugzilla.redhat.com/enter_bug.cgi?product=Fedora&component=java-17-openjdk&version=36
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#

See the log for more info: hs_err_pid161827.log

Seems that the function that is called right before the crash is FileDialog.computeResultChooserDialog().

Environment:

1. Select the platform(s) on which the behavior is seen:

• • All OS
• • Windows
• • [x ] Linux
• • macOS

2. Additional OS info (e.g. OS version, Linux Desktop, etc)
   Fedora 36, GTK 4.6.5

3. JRE/JDK version
   OpenJDK Runtime Environment 21.9 (17.0.3+7) (build 17.0.3+7)

Tracked in #228

[joel-majano]

Narrowed it down a bit more, FileDialog crashes if you select a file when the option SWT.MULTI is used.

In GTK3 gtk_file_chooser_get_files returns a GSList* but in GTK4, it retruns a GListModel*. The rest of the computeResultChooserDialog function assumes that we are dealing with a GSList which is incorrect.

Two lines (I believe) need to be changed using an if(GTK.GTK4) guard in FileDialog.java

1. line 123 needs to be changed to use g_list_model_get_n_items
2. line 128 needs to be changed to use g_list_model_get_object