Skip to content

OpenVi: Portable OpenBSD vi for UNIX systems

License

Notifications You must be signed in to change notification settings

johnsonjh/OpenVi

Repository files navigation

Uma tradução em português está disponível.

OpenVi

OpenVi — Portable OpenBSD vi / ex

Table of Contents

Overview

OpenVi is an enhanced and portable implementation of the Berkeley vi / ex text editor, originally developed by Bill Joy.

OpenVi is a fork of the vi / ex editor included with OpenBSD, which is derived from version 1.79 of the nvi editor originally distributed as part of the Fourth Berkeley Software Distribution (4BSD).

The nvi editor was developed by Keith Bostic of the Computer Systems Research Group (CSRG) at the University of California, Berkeley, Sven Verdoolaege, and other contributors. Nvi itself was derived from Steve Kirkendall's Elvis editor.

Why?

Why would you want to use OpenVi instead of AnotherVi?

  • Derived from the (extensively audited) OpenBSD base system code
    • Focus on readability, simplicity, and correctness of implementation
    • Adherence to OpenBSD's standard secure coding practices
      • Uses secure functions (e.g. strlcpy, snprintf, mkstemp, pledge)
    • Reduced complexity for hopefully fewer program defects
  • Clean source code, distributed under a permissive 3-clause BSD license
    • Some support code is distributed under the (more permissive) ISC license
  • Mostly conforming to relevant standards (POSIX, SUS), where applicable
    • Enhancements, non-standard behaviors, and new features are conservatively and sanely implemented with care taken to balance user expectations, complexity, and historical accuracy
  • Extensions such as bserase, expandtab, imctrl, visibletab, etc.
  • Build requires only GNU Make and standard POSIX utilities
    • Easy integration with embedded, minimal, or iteratively bootstrapped environments and distributions (such as Linux From Scratch builds)
  • No compile-time or build-time configuration options
    • Single standard build configuration with no incompatible variants
    • No configuration-specific bugs resulting from untested combinations or rarely exercised code paths
    • Concise and understandable documentation; no subtle platform variations
  • Consistent user interface, script, and map behavior across all platforms
  • Utilizes OpenBSD's extended Spencer-based regular expression engine (also adopted by LLVM, Tcl, etc.) on all supported systems
  • Single, compact, self-contained binary
    • No external data files required at run-time
    • No external library dependencies (other than curses)
      • Suitable for static linking and emergency “rescue” usage
  • All the various tweaks, fixes, improvements, and clean-ups accumulated over 25+ years as part of the OpenBSD base system

Why not?

So, why might you not want to use OpenVi, then?

Some of these points might be desirable features, depending on your point of view.

  • Internationalization support is currently lacking
    • No support for Unicode / UTF-8 / wide character display
      • Multibyte characters are shown as individual bytes, rather than glyphs
      • Multibyte support is planned, but is unfortunately non-trivial, see:
        • Schwarze, I. (2016, September 25). Keep multibyte character support simple [Conference presentation]. EuroBSDCon 2016 Convention, Belgrade, Serbia. [pdf:OpenBSD]
        • Jun-ichiro itojun Hagino [KAME Project] and Yoshitaka Tokugawa [WIDE Project]. (1999, 6 June). Multilingual vi clones: past, now and the future [Conference presentation]. In Proceedings of the annual conference on USENIX, Annual Technical Conference (USENIX ATEC '99). USENIX Association, Monterey, CA, USA, Page 45. [doi:10.5555/1268708.1268753], [abstract:USENIX] (legacy)
    • No support for bidirectional text
    • No support for regional localization or message translation
  • Inefficient handling of extremely large (e.g. multi-GB) files
  • No support for syntax highlighting, context-aware code completion, code folding, or “language server” integrations
  • No interactive macro recording and debugging functionality
  • No advanced scripting support (no BASIC, COBOL, JavaScript, Lua, Perl, PHP, Python, REXX, Ruby, S-Lang, Tcl, or anything else)
  • Only curses-based visual-mode and line-based ex-mode interfaces available
    • No support for X11/Wayland, OpenGL/Vulkan, Neuralink, augmented / virtual reality, or any other graphical user interfaces

Building

Prerequisites

Required prerequisites

  • POSIX.1-2008 environment: POSIX shell (sh) and utilities, Awk (mawk, nawk), etc.
  • GNU Make (version 3.81 or later)
  • C99 compiler (e.g. xlc, suncc, clang, gcc, etc.)
  • Curses (ncurses, NetBSD curses V8+, PDCurses V2.8+, PDCursesMod, etc.)

Optional prerequisites

  • Perl 5+
  • C shell (csh, tcsh, etc.)
  • nroff, groff, etc.

Supported platforms

  • OpenVi is easily portable to most platforms with UNIX-like operating systems that are mostly conforming to the programming interface described by IEEE Std 1003.1-2008 and user environment described by IEEE Std 1003.2-2008, also known as POSIX.1-2008 and POSIX.2-2008, respectively.

  • The following operating systems are fully supported and regularly tested using ix86/AMD64, ARM/AArch64, m68k, MIPS, POWER, and RISC-V processors:

    • IBM AIX 7.1+
    • Apple Darwin (macOS / Mac OS X) (ARM64, Intel, PowerPC)
    • FreeBSD 12.3+
    • GNU/Linux distributions (glibc, musl)
    • illumos OpenIndiana Hipster
    • NetBSD 9+
    • OpenBSD 6.9+
    • Oracle Solaris 11+
    • Microsoft Windows (Cygwin, Midipix, MSYS2, WSL)
  • The following compilers are fully supported and regularly tested:

    • LLVM Clang (BSD, Darwin, illumos, Linux, Solaris, Windows) V6+
    • AMD Optimizing C/C++ (Linux) V3+
    • GNU GCC (AIX, BSD, Darwin, illumos, Linux, Solaris, Windows) V4.6+
    • IBM Advance Toolchain (Linux on POWER) V14.0+
    • IBM Open XL C/C++ (AIX) V17.1+
    • IBM XL C/C++ (AIX, Linux) V16.1+
    • Intel oneAPI DPC++/C++ (Linux) V2021+
    • Intel C Compiler Classic (Darwin, Linux) V19.1+
    • Oracle Developer Studio (Linux, Solaris) V12.6+
    • PCC Portable C Compiler (NetBSD) V1.0.0+

Newer or older operating system and compiler releases, within reason, should work. The versions listed above are those regularly tested and known working.

Unsupported platforms
  • The following platforms are not currently supported, but support is planned for a future release:
    • Haiku Walter
    • SGI IRIX

User contributions to enhance platform support are welcomed.

Compilation

  • Compilation can be performed by invoking GNU Make (usually gmake or make) from the top-level directory of a source release or git checkout.
  • GNU Make's -j N flag may be used to parallelize the compilation, where N is a positive integer representing the number of parallel jobs requested.
  • The following environment variables influence compilation and installation:
    • CC - C compiler to use
      • (e.g. CC=gcc)
    • OPTLEVEL - Optimization flags
      • (e.g. OPTLEVEL=-O2)
    • CFLAGS - Flags to pass to the C compiler
      • (e.g. CFLAGS="-Wall -pipe")
    • LIBS - Libraries (overriding defaults) to pass to the linker
      • (e.g. LIBS="-lpdcurses -lflock")
    • LDFLAGS - Flags to pass to the linker
      • (e.g. LDFLAGS="-L/lib/path -static")
    • V - Set to enable verbose compilation output
      • (e.g. V=1)
    • DEBUG - Set to compile a debugging build
      • (e.g. DEBUG=1)
    • LGC - Set to enable link-time garbage collection
      • (e.g. LGC=1)
    • LTO - Set to enable link-time optimization
      • (e.g. LTO=1)
    • EXTRA_LIBS - Extra libraries for linking
      • (e.g. EXTRA_LIBS=-lmtmalloc)
    • PREFIX - Directory prefix for use with install and uninstall targets
      • (e.g. PREFIX=/opt/OpenVi)
  • The usual targets (all, strip, superstrip, clean, distclean, install, install-strip, uninstall, upx, etc.) are available; review the GNUmakefile to see all the available targets and options.

For example, to compile an aggressively size-optimized build, enabling link-time optimization and link-time garbage collection, explicitly using GCC:

env CC=gcc OPTLEVEL=-Os LGC=1 LTO=1 gmake sstrip

or, to verbosely compile a debugging build, explicitly using Clang:

env CC=clang DEBUG=1 V=1 gmake

For systems with GNU Make as make (e.g. GNU/Linux), basic compilation should succeed without any options or additional configuration needed:

make

With the appropriate privileges to manipulate files within the chosen PREFIX (using doas, sudo, su, etc.), the compiled executable may be installed — as-is or stripped — using an invocation such as:

doas gmake install-strip

or

sudo env PREFIX=/usr/local make install

Platform Specifics

The following sections document only platform specific differences, and are not intended to be a general or exhaustive reference. For installation of prerequisite software packages or other system configuration, consult the vendor's documentation.

AIX
  • Before building OpenVi on AIX, install the ncurses libraries and headers. IBM provides the necessary packages, ncurses and ncurses-devel, in RPM format as part of the AIX Toolbox for Linux and Open Source Software. With the appropriate permissions (e.g. root), these packages are installable on most systems using the dnf or yum utilities, for example:

    dnf install ncurses ncurses-devel

    or

    yum install ncurses ncurses-devel

    The IBM AIX base system (and PASE for i, an integrated runtime environment for AIX applications on the IBM i operating system) provides libxcurses, an XPG4/XSI Extended Curses implementation derived from AT&T System V, which is not yet supported for use with OpenVi.

  • Compilation is supported using IBM XL C/C++ V16.1+ (gxlc or xlclang), IBM Open XL C/C++ V17.1+ (ibm-clang), or GNU GCC (usually gcc, gcc-8, gcc-9, gcc-10, gcc-11):

    • Link-time optimization (LTO=1) requires Open XL C/C++ V17.1+. The IBM (AIX Toolbox) and Bull/Atos (Bull Freeware) GCC packages, and IBM XL C/C++ versions earlier than V17.1 are not LTO-enabled.
    • Link-time garbage collection (LGC=1) is not supported on IBM AIX.
    • A 64-bit build is the default on systems operating in 64-bit mode; for a 32-bit build, set the value of the MAIXBITS environment variable to 32 (e.g. export MAIXBITS=32).
    • The value of the CC environment variable must be set to the full path of the compiler (e.g. /opt/freeware/bin/gcc, /opt/IBM/xlC/16.1.0/bin/gxlc, /opt/IBM/openxlC/17.1.0/bin/ibm-clang, etc.) unless the compiler directory is already part of the current PATH.
  • File locking (via flock() as provided by the AIX libbsd library) is non-functional; this will be investigated and corrected in a future release.

  • OpenVi man pages are authored with mandoc and require conversion before use with the AIX man software (which is derived from AT&T UNIX System V.)

NetBSD
  • On NetBSD installations, the default OpenVi builds use the BSD curses library provided by the NetBSD base system. To use ncurses instead, set the values of the CFLAGS, LDFLAGS, and CURSESLIB environment variables appropriately (i.e. CFLAGS=-I/usr/pkg/include LDFLAGS=-L/usr/pkg/lib CURSESLIB=-lncurses).

  • The LLVM LLD linker is required for link-time optimization (LTO=1) using Clang. It is available as an installable package (i.e. pkgin install lld).

illumos
  • Before building OpenVi on an illumos distribution (i.e. OpenIndiana), install the ncurses libraries and headers. The OpenIndiana distribution provides the necessary ncurses package in IPS format. With the appropriate permissions (e.g. root), the package can be installed using the OpenIndiana pkg utility, for example:

    pkg install ncurses

    The OpenIndiana base system provides libcurses, an XPG4/XSI Extended Curses implementation derived from AT&T System V, which is not yet supported for use with OpenVi.

  • Link-time garbage collection (LGC=1) is not supported on OpenIndiana.

Solaris
  • Before building OpenVi on Oracle Solaris 11, install the ncurses libraries and headers. Oracle provides provides the necessary ncurses package for Solaris 11 in IPS format. With the appropriate permissions (e.g. root), the package can be installed using the Solaris pkg utility, for example:

    pkg install ncurses

    The base Oracle Solaris system provides libcurses, an XPG4/XSI Extended Curses implementation derived from AT&T System V, which is not yet supported for use with OpenVi.

  • Compilation is supported using Oracle Developer Studio, GCC, and Clang:

    • When using Oracle Developer Studio, invoke the compiler as suncc or set the value of the _OSLCC environment variable to 1.
    • Link-time optimization (LTO=1) is currently supported only when using GCC or Clang.
    • Link-time garbage collection (LGC=1) is not supported on Solaris.
    • When using the Oracle Developer Studio (suncc) compiler, a 64-bit build is the default on systems operating in 64-bit mode; for a 32-bit build, set the value of the SUNBITS environment variable to 32 (e.g. export SUNBITS=32).
  • File locking is unavailable due to the absence of flock() on Solaris. This will be addressed by supporting System V-style fcntl() locking in a future release.

Windows
  • Microsoft Windows supports various development and runtime environments, including MSVC, Cygwin, Midipix, MSYS2, UWIN, the Git Bash environment, and others. Care must be taken to avoid mixing incompatible libraries and tools.
Cygwin
  • Compilation problems in the Cygwin environment are often caused by incomplete or interrupted package installations, or by the installation of packages using non-standard tools (e.g. apt-cyg), which can result in missing files and dangling or missing symbolic links.
  • Before compiling OpenVi under Cygwin, it is highly recommended to:
    • Update the Cygwin setup.exe application to the latest available version.
    • Update all installed packages using the new Cygwin setup.exe application.
    • Install the required prerequisite packages (i.e. make, gcc, ncurses, ncurses-devel) using the Cygwin setup.exe application.
    • Invoke the cygcheck utility (i.e. cygcheck -cv | grep -v "OK$") to verify the integrity of all currently installed packages.

Availability

Source Code

Packages

OpenVi is available to Linux and macOS users via the Homebrew package manager.

Homebrew

brew install openvi

Other (unofficial) distribution packages may be available.

Packaging status

Versioning

The OpenVi version number is based on the version of the corresponding OpenBSD release, followed by the OpenVi release number. The version command can be used to display this information in the format shown below.

Version 7.0.1 (OpenVi) 10/25/2021.

This message indicates the editor in use is OpenVi, release 1, derived from OpenBSD version 7.0, and is fully synchronized with the OpenBSD versions of vi, ex, db, and regex as of 10/25/2021 (October 25th 2021).

Changes not derived from OpenBSD commits do not advance this date. New OpenBSD releases do not reset the OpenVi release number.

History

License

  • OpenVi is distributed under the terms of a 3-clause BSD license.
  • See the LICENSE.md file for the full license and distribution terms.

Acknowledgements

  • rqsd of Libera.Chat for the idea that inspired the project and testing.
  • S. V. Nickolas, Jason Stevens, and the Virtually Fun Discord community, for support and feedback.
  • From the original vi acknowledgements (by Bill Joy & Mark Horton):
    • Bruce Englar encouraged the early development of this display editor.
    • Peter Kessler helped bring sanity to version 2's command layout.
    • Bill Joy wrote version 1, versions 2.0 through 2.7, and created the framework that users see in the present editor.
    • Mark Horton added macros and other features, and made the editor work on a large number of terminals and UNIX systems.
    • The financial support of UUNET Communications Services is gratefully acknowledged.

Similar Projects

  • Martin Guy's Xvi, an enhanced fork of Tim Thompson's STEVIE
  • S. V. Nickolas' Sivle, a cleaned-up fork of Steve Kirkendall's Elvis
  • Andy Valencia's Vim57, a simplified fork of version 5.7 of Bram Moolenaar's Vim

See Also

  • Carsten Kunze's vi is a currently maintained fork of the original (1BSD/2BSD) branch of the vi / ex editor, derived from Gunnar Ritter's enhanced version of the traditional vi editor.
  • Nvi2 is a currently maintained feature branch of the new (4BSD) version of the nvi / nex editor, with a focus on extensibility and new features.
  • Nvi1 (version 1.8+) is the currently maintained traditional branch of the new (4BSD) version of the nvi / nex editor, now developed by Sven Verdoolaege.