Apache HTTP Server Version 2.4

Apache > HTTP Server > Documentation > Version 2.4 > Platform Specific Notes

# Compiling Apache for Microsoft Windows

There are many important points to consider before you begin compiling Apache HTTP Server (httpd). See Using Apache HTTP Server on Microsoft Windows before you begin.

httpd can be built on Windows using a cmake-based build system or with Visual Studio project files maintained by httpd developers. The cmake-based build system directly supports more versions of Visual Studio but currently has considerable functional limitations.

## Building httpd with the included Visual Studio project files

### Requirements

Compiling Apache requires the following environment to be properly installed:

- Disk Space

  Make sure you have at least 200 MB of free disk space available. After installation Apache requires approximately 80 MB of disk space, plus space for log and cache files, which can grow rapidly. The actual disk space requirements will vary considerably based on your chosen configuration and any third-party modules or libraries, especially when OpenSSL is also built. Because many files are text and very easily compressed, NTFS filesystem compression cuts these requirements in half.

- Appropriate Patches

  The httpd binary is built with the help of several patches to third party packages, which ensure the released code is buildable and debuggable. These patches are available and distributed from http://www.apache.org/dist/httpd/binaries/win32/patches_applied/ and are recommended to be applied to obtain identical results as the "official" ASF distributed binaries.

- Microsoft Visual C++ 6.0 (Visual Studio 97) or later.

  Apache can be built using the command line tools, or from within the Visual Studio IDE Workbench. The command line build requires the environment to reflect the `PATH`, `INCLUDE`, `LIB` and other variables that can be configured with the `vcvars32.bat` script.

  You may want the Visual Studio Processor Pack for your older version of Visual Studio, or a full (not Express) version of newer Visual Studio editions, for the ml.exe assembler. This will allow you to build OpenSSL, if desired, using the more efficient assembly code implementation.
  Only the Microsoft compiler tool chain is actively supported by the active httpd contributors. Although the project regularly accepts patches to ensure MinGW and other alternative builds work and improve upon them, they are not actively maintained and are often broken in the course of normal development.

- Updated Microsoft Windows Platform SDK, February 2003 or later.

  An appropriate Windows Platform SDK is included by default in the full (not express/lite) versions of Visual C++ 7.1 (Visual Studio 2002) and later, these users can ignore these steps unless explicitly choosing a newer or different version of the Platform SDK.

  To use Visual C++ 6.0 or 7.0 (Studio 2000 .NET), the Platform SDK environment must be prepared using the `setenv.bat` script (installed by the Platform SDK) before starting the command line build or launching the msdev/devenv GUI environment. Installing the Platform SDK for Visual Studio Express versions (2003 and later) should adjust the default environment appropriately.

  `"c:\Program Files\Microsoft Visual Studio\VC98\Bin\VCVARS32"
  "c:\Program Files\Platform SDK\setenv.bat"`

- Perl and awk

  Several steps recommended here require a perl interpreter during the build preparation process, but it is otherwise not required.

  To install Apache within the build system, several files are modified using the `awk.exe` utility. awk was chosen since it is a very small download (compared with Perl or WSH/VB) and accomplishes the task of modifying configuration files upon installation. Brian Kernighan's http://www.cs.princeton.edu/~bwk/btl.mirror/ site has a compiled native Win32 binary, http://www.cs.princeton.edu/~bwk/btl.mirror/awk95.exe which you must save with the name `awk.exe` (rather than `awk95.exe`).

  If awk.exe is not found, Makefile.win's install target will not perform substitutions in the installed .conf files. You must manually modify the installed .conf files to allow the server to start. Search and replace all "@token@" tags as appropriate.
  The Visual Studio IDE will only find `awk.exe` from the PATH, or executable path specified in the menu option Tools -> Options -> (Projects ->) Directories. Ensure awk.exe is in your system path.
  Also note that if you are using Cygwin tools (http://www.cygwin.com/) the awk utility is named `gawk.exe` and that the file `awk.exe` is really a symlink to the `gawk.exe` file. The Windows command shell does not recognize symlinks, and because of this building InstallBin will fail. A workaround is to delete `awk.exe` from the cygwin installation and copy `gawk.exe` to `awk.exe`. Also note the cygwin/mingw ports of gawk 3.0.x were buggy, please upgrade to 3.1.x before attempting to use any gawk port.

- [Optional] zlib library (for `mod_deflate`)

  Zlib must be installed into a `srclib` subdirectory named `zlib`. This must be built in-place. Zlib can be obtained from http://www.zlib.net/ -- the `mod_deflate` is confirmed to work correctly with version 1.2.3.

  `nmake -f win32\Makefile.msc
  nmake -f win32\Makefile.msc test`

- [Optional] OpenSSL libraries (for `mod_ssl` and `ab.exe` with ssl support)

  The OpenSSL library is cryptographic software. The country in which you currently reside may have restrictions on the import, possession, use, and/or re-export to another country, of encryption software. BEFORE using any encryption software, please check your country's laws, regulations and policies concerning the import, possession, or use, and re-export of encryption software, to see if this is permitted. See http://www.wassenaar.org/ for more information.

  Configuring and building OpenSSL requires perl to be installed.

  OpenSSL must be installed into a `srclib` subdirectory named `openssl`, obtained from http://www.openssl.org/source/, in order to compile `mod_ssl` or the `abs.exe` project, which is ab.c with SSL support enabled. To prepare OpenSSL to be linked to Apache mod_ssl or abs.exe, and disable patent encumbered features in OpenSSL, you might use the following build commands:

  `perl Configure no-rc5 no-idea enable-mdc2 enable-zlib VC-WIN32 -Ipath/to/srclib/zlib -Lpath/to/srclib/zlib
  ms\do_masm.bat
  nmake -f ms\ntdll.mak`

  It is not advisable to use zlib-dynamic, as that transfers the cost of deflating SSL streams to the first request which must load the zlib dll. Note the suggested patch enables the -L flag to work with windows builds, corrects the name of zdll.lib and ensures .pdb files are generated for troubleshooting. If the assembler is not installed, you would add no-asm above and use ms\do_ms.bat instead of the ms\do_masm.bat script.

- [Optional] Database libraries (for `mod_dbd` and `mod_authn_dbm`)

  The apr-util library exposes dbm (keyed database) and dbd (query oriented database) client functionality to the httpd server and its modules, such as authentication and authorization. The sdbm dbm and odbc dbd providers are compiled unconditionally.

  The dbd support includes the Oracle instantclient package, MySQL, PostgreSQL and sqlite. To build these all, for example, set up the LIB to include the library path, INCLUDE to include the headers path, and PATH to include the dll bin path of all four SDK's, and set the DBD_LIST environment variable to inform the build which client driver SDKs are installed correctly, e.g.;

  `set DBD_LIST=sqlite3 pgsql oracle mysql`

  Similarly, the dbm support can be extended with DBM_LIST to build a Berkeley DB provider (db) and/or gdbm provider, by similarly configuring LIB, INCLUDE and PATH first to ensure the client library libs and headers are available.

  `set DBM_LIST=db gdbm`

  Depending on the choice of database distributions, it may be necessary to change the actual link target name (e.g. gdbm.lib vs. libgdb.lib) that are listed in the corresponding .dsp/.mak files within the directories srclib\apr-util\dbd or ...\dbm.

  See the README-win32.txt file for more hints on obtaining the various database driver SDKs.

### Building from Unix sources

The policy of the Apache HTTP Server project is to only release Unix sources. Windows source packages made available for download have been supplied by volunteers and may not be available for every release. You can still build the server on Windows from the Unix source tarball with just a few additional steps.

1. Download and unpack the Unix source tarball for the latest version.
2. Download and unpack the Unix source tarball for latest version of APR, AR-Util and APR-Iconv, place these sources in directories httpd-2.x.x\srclib\apr, httpd-2.x.x\srclib\apr-util and httpd-2.x.x\srclib\apr-iconv
3. Open a Command Prompt and CD to the httpd-2.x.x folder
4. Run the line endings conversion utility at the prompt;

`perl srclib\apr\build\lineends.pl`

You can now build the server with the Visual Studio development environment using the IDE. Command-Line builds of the server are not possible from Unix sources unless you export .mak files as explained below.

### Command-Line Build

`Makefile.win` is the top level Apache makefile. To compile Apache on Windows, simply use one of the following commands to build the `release` or `debug` flavor:

`nmake /f Makefile.win _apacher
nmake /f Makefile.win _apached`

Either command will compile Apache. The latter will disable optimization of the resulting files, making it easier to single step the code to find bugs and track down problems.

You can add your apr-util dbd and dbm provider choices with the additional make (environment) variables DBD_LIST and DBM_LIST, see the comments about [Optional] Database libraries, above. Review the initial comments in Makefile.win for additional options that can be provided when invoking the build.

### Developer Studio Workspace IDE Build

Apache can also be compiled using VC++'s Visual Studio development environment. To simplify this process, a Visual Studio workspace, `Apache.dsw`, is provided. This workspace exposes the entire list of working `.dsp` projects that are required for the complete Apache binary release. It includes dependencies between the projects to assure that they are built in the appropriate order.

Open the `Apache.dsw` workspace, and select `InstallBin` (`Release` or `Debug` build, as desired) as the Active Project. `InstallBin` causes all related project to be built, and then invokes `Makefile.win` to move the compiled executables and dlls. You may personalize the `INSTDIR=` choice by changing `InstallBin`'s Settings, General tab, Build command line entry. `INSTDIR` defaults to the `/Apache2` directory. If you only want a test compile (without installing) you may build the `BuildBin` project instead.

The `.dsp` project files are distributed in Visual Studio 6.0 (98) format. Visual C++ 5.0 (97) will recognize them. Visual Studio 2002 (.NET) and later users must convert `Apache.dsw` plus the `.dsp` files into an `Apache.sln` plus `.msproj` files. Be sure you reconvert the `.msproj` file again if its source `.dsp` file changes! This is really trivial, just open `Apache.dsw` in the VC++ 7.0 IDE once again and reconvert.

There is a flaw in the .vcproj conversion of .dsp files. devenv.exe will mis-parse the /D flag for RC flags containing long quoted /D'efines which contain spaces. The command:

`perl srclib\apr\build\cvtdsp.pl -2005`

will convert the /D flags for RC flags to use an alternate, parseable syntax; unfortunately this syntax isn't supported by Visual Studio 97 or its exported .mak files. These /D flags are used to pass the long description of the mod_apachemodule.so files to the shared .rc resource version-identifier build.
Building with OpenSSL 1.1.0 and up Due to difference in the build structure of OpenSSL begining with version 1.1.0 you will need to convert the dsp files affected with cvtdsp.pl from APR 1.6 or greater. The command:

`perl srclib\apr\build\cvtdsp.pl -ossl11`

Visual Studio 2002 (.NET) and later users should also use the Build menu, Configuration Manager dialog to uncheck both the `Debug` and `Release` Solution modules `abs`, `mod_deflate` and `mod_ssl` components, as well as every component starting with `apr_db*`. These modules are built by invoking `nmake`, or the IDE directly with the `BinBuild` target, which builds those modules conditionally if the `srclib` directories `openssl` and/or `zlib` exist, and based on the setting of `DBD_LIST` and `DBM_LIST` environment variables.

### Exporting command-line .mak files

Exported `.mak` files pose a greater hassle, but they are required for Visual C++ 5.0 users to build `mod_ssl`, abs (`ab` with SSL support) and/or `mod_deflate`. The .mak files also support a broader range of C++ tool chain distributions, such as Visual Studio Express.

You must first build all projects in order to create all dynamic auto-generated targets, so that dependencies can be parsed correctly. Build the entire project from within the Visual Studio 6.0 (98) IDE, using the `BuildAll` target, then use the Project Menu Export for all makefiles (checking on "with dependencies".) Run the following command to correct absolute paths into relative paths so they will build anywhere:

`perl srclib\apr\build\fixwin32mak.pl`

You must type this command from the top level directory of the httpd source tree. Every `.mak` and `.dep` project file within the current directory and below will be corrected, and the timestamps adjusted to reflect the `.dsp`.

Always review the generated `.mak` and `.dep` files for Platform SDK or other local, machine specific file paths. The `DevStudio\Common\MSDev98\bin\` (VC6) directory contains a `sysincl.dat` file, which lists all exceptions. Update this file (including both forward and backslashed paths, such as both `sys/time.h` and `sys\time.h`) to ignore such newer dependencies. Including local-install paths in a distributed `.mak` file will cause the build to fail completely.

If you contribute back a patch that revises project files, we must commit project files in Visual Studio 6.0 format. Changes should be simple, with minimal compilation and linkage flags that can be recognized by all Visual Studio environments.

### Installation

Once Apache has been compiled, it needs to be installed in its server root directory. The default is the `\Apache2` directory, of the same drive.

To build and install all the files into the desired folder dir automatically, use one of the following `nmake` commands:

`nmake /f Makefile.win installr INSTDIR=dir
nmake /f Makefile.win installd INSTDIR=dir`

The dir argument to `INSTDIR` provides the installation directory; it can be omitted if Apache is to be installed into `\Apache22` (of the current drive).

### Warning about building Apache from the development tree

Note only the `.dsp` files are maintained between `release` builds. The `.mak` files are NOT regenerated, due to the tremendous waste of reviewer's time. Therefore, you cannot rely on the `NMAKE` commands above to build revised `.dsp` project files unless you then export all `.mak` files yourself from the project. This is unnecessary if you build from within the Microsoft Developer Studio environment.

## Building httpd with cmake

The primary documentation for this build mechanism is in the `README.cmake` file in the source distribution. Refer to that file for detailed instructions.

Building httpd with cmake requires building APR and APR-util separately. Refer to their `README.cmake` files for instructions.

The primary limitations of the cmake-based build are inherited from the APR-util project, and are listed below because of their impact on httpd:

- No cmake build for the APR-iconv subproject is available, and the APR-util cmake build cannot consume an existing APR-iconv build. Thus, `mod_charset_lite` and possibly some third-party modules cannot be used.
- The cmake build for the APR-util subproject does not support most of the optional DBM and DBD libraries supported by the included Visual Studio project files. This limits the database backends supported by a number of bundled and third-party modules.