Fluid: potential memory leaks

[Albrecht-S]

I'm aware that memory leaks reported by tools like valgrind and/or address sanitizer (ASAN) may be false positives and can often be ignored. I removed all common and well-known reports from fontconfig etc. anyway.

The remaining reports seem to be related to the new DesignViewer and Fl_Preferences.

@MatthiasWM Please check if these reports are relevant and feel free to close this issue if not. Thanks.

Tested on Linux with current git (410e57d). Run fluid about_panel.fl and close the main window immediately after it opens. No other actions required. In my tests the code view was not opened at all. I used about_panel.fl because it's small but I saw similar reports with other fluid files as well.

Part 1: valgrind

$ valgrind --leak-check=full bin/fluid ../../fluid/about_panel.fl

28 bytes in 1 blocks are definitely lost in loss record 381 of 1,593
   at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x514D38E: strdup (strdup.c:42)
   by 0x2E4F77: Fl_Posix_System_Driver::strdup(char const*) (Fl_Posix_System_Driver.H:84)
   by 0x2B05D3: fl_strdup (fl_string_functions.cxx:33)
   by 0x262857: Fl_Preferences::get(char const*, char*&, char const*) (Fl_Preferences.cxx:795)
   by 0x2181AA: shell_prefs_get() (shell_command.cxx:55)
   by 0x20B82F: make_main_window() (fluid.cxx:1504)
   by 0x20CF33: main (fluid.cxx:1963)

28 bytes in 1 blocks are definitely lost in loss record 382 of 1,593
   at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x514D38E: strdup (strdup.c:42)
   by 0x2E4F77: Fl_Posix_System_Driver::strdup(char const*) (Fl_Posix_System_Driver.H:84)
   by 0x2B05D3: fl_strdup (fl_string_functions.cxx:33)
   by 0x218323: shell_settings_read() (shell_command.cxx:92)
   by 0x207CEE: read_file(char const*, int, Strategy) (file.cxx:665)
   by 0x20D050: main (fluid.cxx:1983)

1,160 (136 direct, 1,024 indirect) bytes in 1 blocks are definitely lost in loss record 1,419 of 1,593
   at 0x483BE63: operator new(unsigned long) (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x1C796B: DesignViewer::DesignViewer(int, int, int, int, char const*) (CodeEditor.cxx:308)
   by 0x215B71: make_sourceview() (function_panel.cxx:1548)
   by 0x20B4F9: toggle_sourceview_cb(Fl_Double_Window*, void*) (fluid.cxx:1460)
   by 0x20CFE8: main (fluid.cxx:1976)

1,160 (136 direct, 1,024 indirect) bytes in 1 blocks are definitely lost in loss record 1,420 of 1,593
   at 0x483BE63: operator new(unsigned long) (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
   by 0x1C796B: DesignViewer::DesignViewer(int, int, int, int, char const*) (CodeEditor.cxx:308)
   by 0x215D3D: make_sourceview() (function_panel.cxx:1569)
   by 0x20B4F9: toggle_sourceview_cb(Fl_Double_Window*, void*) (fluid.cxx:1460)
   by 0x20CFE8: main (fluid.cxx:1976)

Part 2: LeakSanitizer (ASAN)

Direct leak of 136 byte(s) in 1 object(s) allocated from:
    #0 0x7fc800357587 in operator new(unsigned long) ../../../../src/libsanitizer/asan/asan_new_delete.cc:104
    #1 0x55ead197b942 in DesignViewer::DesignViewer(int, int, int, int, char const*) ../../fluid/CodeEditor.cxx:308
    #2 0x55ead1a13777 in make_sourceview() ../../fluid/function_panel.cxx:1569
    #3 0x55ead1a05fcd in toggle_sourceview_cb(Fl_Double_Window*, void*) ../../fluid/fluid.cxx:1460
    #4 0x55ead1a09419 in main ../../fluid/fluid.cxx:1976
    #5 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Direct leak of 136 byte(s) in 1 object(s) allocated from:
    #0 0x7fc800357587 in operator new(unsigned long) ../../../../src/libsanitizer/asan/asan_new_delete.cc:104
    #1 0x55ead197b942 in DesignViewer::DesignViewer(int, int, int, int, char const*) ../../fluid/CodeEditor.cxx:308
    #2 0x55ead1a13569 in make_sourceview() ../../fluid/function_panel.cxx:1548
    #3 0x55ead1a05fcd in toggle_sourceview_cb(Fl_Double_Window*, void*) ../../fluid/fluid.cxx:1460
    #4 0x55ead1a09419 in main ../../fluid/fluid.cxx:1976
    #5 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Direct leak of 28 byte(s) in 1 object(s) allocated from:
    #0 0x7fc8002de3ed in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cc:445
    #1 0x55ead1b5d3c9 in Fl_Posix_System_Driver::strdup(char const*) ../../src/drivers/Unix/../Posix/Fl_Posix_System_Driver.H:84
    #2 0x55ead1b45cd0 in fl_strdup ../../src/fl_string_functions.cxx:33
    #3 0x55ead1aa3239 in Fl_Preferences::get(char const*, char*&, char const*) ../../src/Fl_Preferences.cxx:795
    #4 0x55ead1a16d18 in shell_prefs_get() ../../fluid/shell_command.cxx:55
    #5 0x55ead1a06697 in make_main_window() ../../fluid/fluid.cxx:1504
    #6 0x55ead1a09358 in main ../../fluid/fluid.cxx:1963
    #7 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Direct leak of 28 byte(s) in 1 object(s) allocated from:
    #0 0x7fc8002de3ed in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cc:445
    #1 0x55ead1b5d3c9 in Fl_Posix_System_Driver::strdup(char const*) ../../src/drivers/Unix/../Posix/Fl_Posix_System_Driver.H:84
    #2 0x55ead1b45cd0 in fl_strdup ../../src/fl_string_functions.cxx:33
    #3 0x55ead1a16eb2 in shell_settings_read() ../../fluid/shell_command.cxx:92
    #4 0x55ead19ff404 in read_file(char const*, int, Strategy) ../../fluid/file.cxx:665
    #5 0x55ead1a094ae in main ../../fluid/fluid.cxx:1983
    #6 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Indirect leak of 1024 byte(s) in 1 object(s) allocated from:
    #0 0x7fc800355808 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cc:144
    #1 0x55ead1ad8374 in Fl_Text_Buffer::Fl_Text_Buffer(int, int) ../../src/Fl_Text_Buffer.cxx:108
    #2 0x55ead197b958 in DesignViewer::DesignViewer(int, int, int, int, char const*) ../../fluid/CodeEditor.cxx:308
    #3 0x55ead1a13569 in make_sourceview() ../../fluid/function_panel.cxx:1548
    #4 0x55ead1a05fcd in toggle_sourceview_cb(Fl_Double_Window*, void*) ../../fluid/fluid.cxx:1460
    #5 0x55ead1a09419 in main ../../fluid/fluid.cxx:1976
    #6 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Indirect leak of 1024 byte(s) in 1 object(s) allocated from:
    #0 0x7fc800355808 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cc:144
    #1 0x55ead1ad8374 in Fl_Text_Buffer::Fl_Text_Buffer(int, int) ../../src/Fl_Text_Buffer.cxx:108
    #2 0x55ead197b958 in DesignViewer::DesignViewer(int, int, int, int, char const*) ../../fluid/CodeEditor.cxx:308
    #3 0x55ead1a13777 in make_sourceview() ../../fluid/function_panel.cxx:1569
    #4 0x55ead1a05fcd in toggle_sourceview_cb(Fl_Double_Window*, void*) ../../fluid/fluid.cxx:1460
    #5 0x55ead1a09419 in main ../../fluid/fluid.cxx:1976
    #6 0x7fc7ff827082 in __libc_start_main ../csu/libc-start.c:308

Note: Leak Sanitizer (ASAN) can be used with g++ and/or clang++. If you need help to set up ASAN support I can give some hints. Note that you can't run programs instrumented with ASAN by using valgrind (it's not compatible).

[MatthiasWM]

Valgrind message 1 and 2 are not an issue because allocation are not accumulating while FLUID is running. The same is true for 3 and 4, but I fixed those nevertheless because there was a naming issue.

The ASAN leaks point to the same issues.

817a97b should fix 3 and 4, and even 1 and 2 (but no similar cases)

[Albrecht-S]

Thanks for fixing "3 and 4" and for clarification.

FTR: the remaining "non-leaks" found by ASAN are reported:

Direct leak of 28 byte(s) in 1 object(s) allocated from:
    #0 0x7f501287c3ed in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cc:445
    #1 0x5620f95745fd in Fl_Posix_System_Driver::strdup(char const*) ../../src/drivers/Unix/../Posix/Fl_Posix_System_Driver.H:84
    #2 0x5620f955cf04 in fl_strdup ../../src/fl_string_functions.cxx:33
    #3 0x5620f94ba455 in Fl_Preferences::get(char const*, char*&, char const*) ../../src/Fl_Preferences.cxx:795
    #4 0x5620f942ddc2 in shell_prefs_get() ../../fluid/shell_command.cxx:55
    #5 0x5620f941d703 in make_main_window() ../../fluid/fluid.cxx:1504
    #6 0x5620f94203c4 in main ../../fluid/fluid.cxx:1963
    #7 0x7f5011dc5082 in __libc_start_main ../csu/libc-start.c:308

Direct leak of 28 byte(s) in 1 object(s) allocated from:
    #0 0x7f501287c3ed in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cc:445
    #1 0x5620f95745fd in Fl_Posix_System_Driver::strdup(char const*) ../../src/drivers/Unix/../Posix/Fl_Posix_System_Driver.H:84
    #2 0x5620f955cf04 in fl_strdup ../../src/fl_string_functions.cxx:33
    #3 0x5620f942df5c in shell_settings_read() ../../fluid/shell_command.cxx:92
    #4 0x5620f9416470 in read_file(char const*, int, Strategy) ../../fluid/file.cxx:665
    #5 0x5620f942051a in main ../../fluid/fluid.cxx:1983
    #6 0x7f5011dc5082 in __libc_start_main ../csu/libc-start.c:308

Thanks. Closing the issue as completed.