1 With the author's permission, SimGear now bundles MetaKit. MetaKit is
4 The MetaKit Library 2.01 March 2000
5 ==============================================================================
8 WHAT IT IS - MetaKit is an embeddable database which runs on Unix, Windows,
9 Macintosh, and other platforms. It lets you build applications which
10 store their data efficiently, in a portable way, and which will not need a
11 complex runtime installation. In terms of the data model, MetaKit takes
12 the middle ground between RDBMS, OODBMS, and flat-file databases - yet it
13 is quite different from each of them.
15 WHAT IT ISN'T - MetaKit is not: 1) multi-user/-threading, 2) scalable to
16 gigabytes, 3) proprietary software, 4) full of bugs, 5) just a toy.
18 TECHNOLOGY - Everything is stored variable-sized yet with efficient positional
19 row access. Changing an existing datafile structure is as simple as re-
20 opening it with that new structure. All changes are transacted. You can
21 mix and match software written in C++, Python, and Tcl. Things can't get
24 CORE - The Metakit core library is written in C++. It has a code footprint of
25 just over 100 Kb on Windows. It can be used as DLL, or linked statically.
26 Debug builds include extensive assertion checks to catch problems early.
28 PYTHON - The binding for Python is called "Mk4py". It uses SCXX by Gordon
29 McMillan as C++ glue interface. The source is in directory "python/".
31 TCL/TK - The MK extension for Tcl is called "Mk4tcl". It is being used in a
32 number of commercial projects, for in-house use as well as in commercially
33 distributed products. The source is in directory "tcl/".
35 LICENSE AND SUPPORT - MetaKit 2.01 is distributed as open source software (the
36 X/MIT-style license is at the end of this document). Commercial support
37 is available through an Enterprise License, see the URL mentioned below.
39 DOCUMENTATION - All documentation uses HTML. The main page is "MetaKit.html",
40 which leads to the rest of the documentation in the "doc/" directory.
42 WEBSITE URLS - The main pages on the world wide web, for news and downloads:
43 Homepage: http://www.equi4.com/metakit/
44 Python news: http://www.equi4.com/metakit/python.html
45 Tcl/Tk news: http://www.equi4.com/metakit/tcl.html
46 License info: http://www.equi4.com/metakit/license.html
47 Contact info: http://www.equi4.com/contact.html
53 Starting with this release, all platform builds and language bindings are now
54 designed to work from a single common "builds/" directory. It turns out to
55 be impossible to keep build side-effects limited to *just* this directory
56 (CodeWarrior can't be told where to place its temp data, and Visual C++ still
57 alters a few files next to the project ".dsw" file, to name two offenders).
61 It is no longer advised to build the Unix code in the "unix/" directory.
62 Instead, you should perform the following steps:
67 And optionally (this only installs the core lib, not script extensions):
70 By switching to the "builds/" directory, you will keep the distribution
71 directory tree 100% unaltered. All changes are made in this subdir, and
72 all final build results are left behind in this same subdir.
74 Nastiness: if you build Mk4tcl, please do a "make Mk4tcl.so" as well.
75 And if you intend to create the Python extension, do a "make Mk4py.so".
76 The "libmk4tcl.so.0.0.0" and "libMk4py.so.0.0.0" targets are bogus ones.
78 You will probably have to make changes in the makefile to locate the
79 proper includes and libs for Python (Tcl has been fixed, see "--with-tcl).
80 You probably only need to adjust "CXX_SWITCHES_PY" to find the headers.
82 To build with STL containers and strings, you can do the following:
83 make CXXFLAGS='-Dq4_STD' test # add -O3 etc, as needed
84 This passes the test suite on Linux RedHat 5.2 with gcc 2.95-2.
86 See below for some platform-specific build notes.
90 There is a "win/" directory which contains subdirectories for a number of
91 compiler systems. MetaKit has been built with many different compilers
92 in the past (Microsoft, Borland, Watcom, Symantec, Metrowerks, Optima),
93 but to preserve my sanity (there are 12 configurations for MSVC6 alone!),
94 I am limiting myself to MSVC6, MWCW5, Borland C++ Builder 4, and Cygwin.
96 The MS Visual C++ 6.0 project is "win/msvc60/mksrc.dsw", with subprojects
97 for the C++ demo (mkdemo), building dll's (mkdll), static libs (mklib),
98 regression tests (mktest), as well as Tcl (mktcl) and Python (mkpython).
99 It has been set up to place all intermediate files and final results in
100 the "builds/" subdirectory, even though you'll launch it from "win/".
102 To build with STL containers and strings under MSVC, define "q4_STD".
103 To build with MFC containers and strings under MSVC, define "q4_MFC".
105 The Metrowerks Codewarrior project is in the "mac/" directory, and can be
106 used to build both Mac and Windows versions (on either Mac *or* Windows).
107 The core libraries are built with "mac/cw5.mcp", demos / tests are built
108 with "cw5apps.mcp", Tcl is "cw5tcl.mcp", and Python is "cw5python.mcp".
110 The Borland C++ Builder projects have not yet been incorporated in this
111 release, but the "KitViewer" application is an example of how to use BCB.
113 The Cygwin build (B20.1 / gcc 2.95.2) is different, because it uses the
114 unix autoconf system, and must be launched as described above for UNIX.
115 I have upgraded to the latest development of libtool to be able to build
116 DLL's with Cygwin. You can build the "-mno-cygwin" version by editing
117 the Makefile by hand and adding that option to CXXFLAGS.
119 Rob Bloodgood adds that the following GCC options are for maximum code
120 efficiency on x86 hardware: "-O2 -m486 -malign-loops=2 -malign-jumps=2".
121 I have not yet tried this myself, but am passing on the tip.
125 The Mac version requires Metrowerks CodeWarrior 5. See the info above
126 in the Windows section (MWCW is multi-platform). The projects are all
127 located in the "mac/" folder, which is also where MWCW will place its own
128 "... Data" folders with intermediate results. As with all other setups,
129 final results are made to end up in the "builds/" directory.
131 Static 68K builds appear to work fine, the 68K CFM variants will need
132 some more work (I couldn't get the libraries to export their symbols).
135 PLATFORM-SPECIFIC NOTES
136 =======================
138 * Linux RH 5.2 / gcc 2.95.2
140 Builds with gcc 2.95.2 work out of the box. The Tcl extension ends up as
141 ".libs/libmk4tcl.so.0.0.0" (to please libtool), and should be renamed to
142 "Mk4tcl.so". Similarly, ".libs/libMk4py.so.0.0.0" is in fact the Python
143 extension, and *must* be renamed to "Mk4py.so" to call it from Python.
145 The core MK libs end up as ".libs/libmk4.a" and ".libs/libmk4.so.0.0.0".
147 * Solaris 2.6 / gcc 2.8.1
149 The Solaris builds are nasty for several reasons:
151 - I do not own such a machine, and often have to make arrangements
152 (or fight limited space on one of the machines I can telnet to).
153 - The gcc 2.8.1 optimizer appears to be buggy, I have had to turn off
154 the default "-O3" flag to prevent compiler crashes (several files).
155 This problems appears to be resolved with gcc 2.95.
156 - Locking on Solaris (especially w.r.t NFS) remains a mystery to me.
157 The Tcl and Python extensions both use locking (the core not yet).
158 See tcl/Mk4tcl.cpp around line 520, and python/PyStorage.cpp around
159 line 80 for details. It's all pretty messy, and not 100% correct.
161 Despite this, I'm doing my best to resolve these issues. Having a solid
162 build of the core *and* of Tcl / Python extensions is quite important.
166 No further notes, though many systems will build fine out of the box.
170 MSVC 6 builds MK as static lib and as DLL (universal config, I have not
171 yet created build versions with MFC or STL, mainly because MK can now be
172 used in all contexts regardless of how it was built). The Python and Tcl
173 extensions build as dynamic extensions (a static build is easy to add).
175 MWCW 5 builds MK as static lib and as DLL (interestingly enough, the DLL
176 is slightly smaller than MSVC 6 - 102 vs 108 Kb - when their runtimes are
177 linked in dynamically as well). I have not added Win builds for Tcl or
178 Python, since MSVC 6 has those already.
180 Cygwin B20.1, with gcc 2.95.2 ugrade, also builds MK as static lib and as
181 DLL. Both "pure" Cygwin (i.e. requiring cygwin1.dll) and mingw32 (using
182 the -mno-cygwin flag) build, but there are some hairy include issues when
183 it comes to choosing the right locking model for Tcl and Python. These
184 issues have not been resolved fully.
188 MWCW 5 builds PPC shared libs, PPC static libs, and 68K static libraries.
190 Building 68K CFM libraries leads to a "MetaKit 68K.shlb" which comes out
191 of the linker without errors, but the result does not seem to have any
192 export symbols defined (despite the fact that the library is over 200 K).
193 Because of that, I've been unable to build apps or Mk4tcl/Mk4py so far.
195 The other three configurations build, but for some reason MK's regression
196 test stops at L03 (everything up to that point looks ok, i.e. over 90%).
198 The Mk4tcl PPC extension appears to work (quick manual test), and so does
199 the Python extension, "Mk4py.PPC.slb". I have not yet given these two
200 a serious workout, hoping to have a basic test harness in place soon.
204 No news yet, please report your findings with any other platform builds.
210 - a section on basic concepts (or maybe it doesn't belong here?)
211 - a section on getting started (C++, Python, Tcl all differ - point to
212 the respective intro pages)
213 - maybe a small sample for each of C++ / Tcl / Python, to give an idea
214 - mention TclKit, scripted docs (WiKit/Tequila?), VFS?
215 - I forgot... please tell me :)
218 LICENSE AND COPYRIGHT STATEMENT
219 ===============================
221 Copyright (c) 1996-2000 Jean-Claude Wippler
223 Permission is hereby granted, free of charge, to any person obtaining a
224 copy of this software and associated documentation files (the "Software"),
225 to deal in the Software without restriction, including without limitation
226 the rights to use, copy, modify, merge, publish, distribute, sublicense,
227 and/or sell copies of the Software, and to permit persons to whom the
228 Software is furnished to do so, subject to the following conditions:
230 The above copyright notice and this permission notice shall be included
231 in all copies or substantial portions of the Software.
233 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
234 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
235 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
236 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
237 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
238 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
239 DEALINGS IN THE SOFTWARE.
242 ==============================================================================
243 -- Jean-Claude Wippler <jcw@equi4.com>