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@variar variar released this
· 6 commits to master since this release

This release brings many new features, performance and usability improvements.

New features

  • Regular expression engine is switched to Hyperscan. This is several times faster than Qt regular expressions. Hyperscan pattern syntax is less expressive, and klogg will automatically switch to Qt engine if needed. Moreover, klogg now allows combining regular expressions with boolean operators (AND, OR, NOT). Hyperscan requires CPU with SSSE3 support. If CPU doesn't have these instructions, then Klogg will switch to Qt regular expression engine.
  • Highlighters configuration has been reworked. Now it is possible to:
    • create several sets of highlighters and apply any number of them to current file
    • assign some text a color label (up to 9 different colors)
    • add variation to slightly change highlight color for a pattern based on actual matching text
    • use alpha-channel for highlight colors
  • Keyboard shortcuts are now configurable via a special configuration dialog
  • There is a predefined filters dialog. It allows creating sets of filters and quickly add them to search expression
  • The limit of number of lines in the log file has been removed. It is now limited by available RAM and CPU resources. The single line length is still limited to around 2^30, this is limitation of QString in Qt5.
  • Context menu for selected text now has more useful actions (replace search, add to scratchpad, etc.)
  • Search history is now editable and includes more items

Bug fixes

  • Crash reports from many users helped to fix issues with putting too much data to clipboard, data races with multiple instances of klogg and multiple windows.
  • A fast file modification detection mode helps to improve performance in case when a large file is opened in follow file mode
  • Dark mode is simplified and looks more solid
  • Klogg no longer hangs in cases when large amount of data is rapidly added to a file
  • Files with utf16 little and big endian are now displayed properly
  • Klogg no longer leaks memory if file in follow mode is left open for days

Internal code structure has been improved to improve memory allocation and multithreading performance. Klogg uses less external dependencies. Build system now allows using more external dependencies from host build system.

System requirements

Klogg requires CPU with at least SSE2 instruction set. For best performance CPU should have SSSE3 and POPCNT instructions.
Supported operating systems: Window 7+, Mac OS 10.14+, Ubuntu LTS 18.04+, Oracle Linux 8+

Precompiled binaries

  • Windows x86 and x64, based on Qt 5.15.2, both installer and portable versions, now signed with valid codesign certificate
  • Linux x64 DEB packages for Ubuntu 18.04, 20.04 and 22.04 as well as RPM package built on Oracle Linux 8
  • Linux x64 AppImage package
  • Mac x64 dmg image and pkg installer, based on Qt 5.15.2, for Intel CPUs
  • Experimental packages for Windows built with Qt 6.2.4, requires Windows 10+.
  • Experimental packages for Mac built with Qt 6.2.4, requires Mac OS 10.15+, for Intel CPUs

An archive with snapshot of klogg dependencies is provided so the build can be reproduced.

Known issues

  • On some Windows 11 systems klogg crashes when trying to show an open file dialog (#484). This is due to an incompatibility between Intel TBB memory allocator and some Windows libraries. In this case setting environmental variable TBB_MALLOC_DISABLE_REPLACEMENT to 1 disables TBB memory allocator, and klogg works as expected.
  • For high dpi displays consider trying klogg build with Qt6. Although these builds are less tested, Qt6 behaves better in high dpi environment (#485).
  • On some systems with Qt 5.9.5 some keyboard shortcuts do not work (#496). Appimage build can be used as a workaround.

Release updates

  • The "report issue" link in menu was broken in build (#486). Binaries have been updated to to fix it.

Big thanks for everyone who provided feedback and feature requests!