01762bd57f
The call to _MakeSpace() may move the extent data from the indirect array (kept in a heap allocation) to the direct one kept inside the class. In that case the lastExtent pointer would become stale and further use of it would've lead to suboptimal extents in the best case to reading/writing at the wrong point in files and possibly corruption of another allocation in the worst (both unlikely though). To mitigate that we now re-initialize the pointer to the correct location if we hit the cache limit. Also made the use of the start variable more understandable. Instaed of decrementing it (possibly wrapping) when an extent wasn't going to be used and later adding the vector index again, just increment whenever we actually move to the next extent. For bad things to happen a few conditions needed to come together though: 1. There needed to be multiple vectors that could be combined with the existing last extent. 2. There first needed to be more extents than the cache limit and that number then had to decrease below the cache limit again. 3. The memory needed to stay intact after being freed up until after the evaluation (or similar enough data had to be written to it). At least the last one was guaranteed to not be true anymore since we re-introduced overwritting freed memory with 0xdeadbeef in the slab, therefore nastily hiding this. I'm not sure that the first condition is ever met either (probably the vectors are combined beforehand so that there never are multiple adjacent ones) at least for the normal use case (the page writer writing back pages). I was at least unable to reproduce an actual file corruption in my testing. Just the out of bounds access to the stale pointer happened rather easily though and is now at least fixed. |
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3rdparty | ||
build | ||
data | ||
docs | ||
headers | ||
src | ||
.gitignore | ||
configure | ||
Jamfile | ||
Jamrules | ||
makehaikufloppy | ||
ReadMe | ||
ReadMe.IntroductionToHaiku |
Building Haiku from source ========================== This is a overview into the process of building HAIKU from source. An online version is available at http://www.haiku-os.org/guides/building/ Official releases of Haiku are at http://www.haiku-os.org/get-haiku The (unstable) nightly builds are available at http://www.haiku-files.org To build Haiku, you will need to * ensure pre-requisite software is installed * download sources * configure your build * run jam to initiate the build process We currently support these platforms: * Haiku * Linux * FreeBSD * Mac OS X Intel Pre-requisite software ====================== Tools provided within Haiku's repositories * Jam (Jam 2.5-haiku-20090626) * Haiku's cross-compiler (needed only for non-Haiku platforms) The tools to compile Haiku will vary, depending on the platform that you are using to build Haiku. When building from Haiku, all of the necessary development tools are included in official releases (e.g. R1 alpha 1) and in the (unstable) nightly builds. * Git client * SSH client (for developers with commit access) * gcc and the binutils (as, ld, etc., required by gcc) * make (GNU make) * bison * flex and lex (usually a mini shell script invoking flex) * makeinfo (part of texinfo, needed for building gcc 4 only) * autoheader (part of autoconf, needed for building gcc) * automake * gawk * yasm (http://www.tortall.net/projects/yasm/wiki/Download) * wget * (un)zip * cdrtools (not genisoimage!) * case-sensitive file system Whether they are installed can be tested for instance by running them in the shell with the "--version" parameter. Specific: Haiku for the ARM platform ------------------------------------ The following tools are needed to compile Haiku for the ARM platform * mkimage (http://www.denx.de/wiki/UBoot) * Mtools (http://www.gnu.org/software/mtools/intro.html) * sfdisk Specific: Mac OS X ------------------ Disk Utility can create a case-sensitive disk image of at least 3 GiB in size. The following darwin ports need to be installed: * expat * gawk * gettext * libiconv * gnuregex * gsed More information about individual distributions of Linux and BSD can be found at http://haiku-os.org/guides/building/pre-reqs Download Haiku's sources ======================== There are two parts to Haiku's sources -- the code for Haiku itself and a set of build tools for compiling Haiku on an operating system other than Haiku. The buildtools are needed only for non-Haiku platform. Anonymous checkout: git clone git://git.haiku-os.org/haiku git clone git://git.haiku-os.org/buildtools Developer with commit access: git clone ssh://git.haiku-os.org/haiku git clone ssh://git.haiku-os.org/buildtools Building the Jam executable =========================== This step applies only to non-Haiku platforms. Change to the buildtools folder and we will start to build 'jam' which is a requirement for building Haiku. Run the following commands to generate and install the tool: cd buildtools/jam make sudo ./jam0 install -- or -- ./jam0 -sBINDIR=$HOME/bin install Configuring your build ====================== The configure script generates a file named "BuildConfig" in the "generated/build" directory. As long as configure is not modified (!), there is no need to call it again. That is for re-building you only need to invoke jam (see below). If you don't update the source tree very frequently, you may want to execute 'configure' after each update just to be on the safe side. Depending on your goal, there are several different ways to configure Haiku. You can either call configure from within your Haiku trunk folder. That will prepare a folder named 'generated', which will contain the compiled objects. Another option is to manually created one or more 'generated.*' folders and run configure from within them. For example imagine the following directory setup buildtools-trunk/ haiku-trunk/ haiku-trunk/generated.x86gcc2 haiku-trunk/generated.x86gcc4 Configure a GCC 2.95 Hybrid, from non-Haiku platform ---------------------------------------------------- cd haiku-trunk/generated.x86gcc4 ../configure --use-gcc-pipe --use-xattr \ --build-cross-tools-gcc4 x86 ../../buildtools/ \ --alternative-gcc-output-dir ../generated.x86gcc2 cd ../generated.x86gcc2 ../configure --use-gcc-pipe --use-xattr \ --build-cross-tools ../../buildtools/ \ --alternative-gcc-output-dir ../generated.x86gcc4 Configure a GCC 2.95 Hybrid, from within Haiku ---------------------------------------------- cd haiku-trunk/generated.x86gcc4 ../configure --use-gcc-pipe \ --alternative-gcc-output-dir ../generated.x86gcc2 \ --cross-tools-prefix /boot/develop/abi/x86/gcc4/tools/current/bin/ cd ../generated.x86gcc2 ../configure --use-gcc-pipe \ --alternative-gcc-output-dir ../generated.x86gcc4 \ --cross-tools-prefix /boot/develop/abi/x86/gcc2/tools/current/bin/ Additional information about GCC Hybrids can be found on the website, http://www.haiku-os.org/guides/building/gcc-hybrid Configure options ----------------- The various runtime options for configure are documented in it's onscreen help ./configure --help Building via Jam ================ Haiku can be built in either of two ways, as disk image file (e.g. for use with emulators, to be written directly to a usb stick, burned as a compact disc) or as installation in a directory. Running Jam ----------- There are various ways in which you can run jam. * If you have a single generated folder, you can run 'jam' from the top level of Haiku's trunk. * If you have one or more generated folders, (e.g. generated.x86gcc2), you can cd into that directory and run 'jam' * In either case, you can cd into a certain folder in the source tree (e.g. src/apps/debugger) and run jam -sHAIKU_OUTPUT_DIR=<path to generated folder> Be sure to read build/jam/UserBuildConfig.ReadMe and UserBuildConfig.sample, as they contain information on customizing your build of Haiku. Building a Haiku anyboot file --------------------------- jam -q haiku-anyboot-image This generates an image file named 'haiku-anyboot.image' in your output directory under 'generated/'. Building a VMware image file ---------------------------- jam -q haiku-vmware-image This generates an image file named 'haiku.vmdk' in your output directory under 'generated/'. Directory Installation ---------------------- HAIKU_INSTALL_DIR=/Haiku jam -q install-haiku Installs all Haiku components into the volume mounted at "/Haiku" and automatically marks it as bootable. To create a partition in the first place use DriveSetup and initialize it to BFS. Note that installing Haiku in a directory only works as expected under Haiku, but it is not yet supported under Linux and other non-Haiku platforms. Building individual components ------------------------------ If you don't want to build the complete Haiku, but only a certain app/driver/etc. you can specify it as argument to jam, e.g.: jam Debugger Alternatively, you can 'cd' to the directory of the component you want to build and run 'jam' from there. Note: if your generated directory named something other than "generated/", you will need to tell jam where it is. jam -sHAIKU_OUTPUT_DIR=<path to generated folder> You can also force rebuilding of a component by using the "-a" parameter: jam -a Debugger Running ======= Generally there are two ways of running Haiku. On real hardware using a partition and on emulated hardware using an emulator like Bochs or QEMU. On Real Hardware ---------------- If you have installed Haiku to its own partition you can include this partition in your bootmanager and try to boot Haiku like any other OS you have installed. To include a new partition in the Haiku bootmanager run this in a Terminal: bootman On Emulated Hardware -------------------- For emulated hardware you should build disk image (see above). How to setup this image depends on your emulater. If you use QEMU, you can usually just provide the path to the image as command line argument to the "qemu" executable. Docbook documentation ===================== Our documentation can be found in 'src/documentation/'. You can build it by running 'jam' in that folder. The results will be stored in the 'generated/' folder.