README.md - pdfium - Git at Google

 # PDFium

 ## Prerequisites

 Get the chromium depot tools via the instructions at
 http://www.chromium.org/developers/how-tos/install-depot-tools (this provides
 the gclient utility needed below).

 Also install Python, Subversion, and Git and make sure they're in your path.


 ### Windows development

 PDFium uses the same build tool as Chromium:

 #### Open source contributors
 Please refer to [Chromium's Visual Studio set up](https://chromium.googlesource.com/chromium/src/+/master/docs/windows_build_instructions.md#visual-studio)
 for requirements and instructions on build environment configuration.

 Run `set DEPOT_TOOLS_WIN_TOOLCHAIN=0`, or set that variable in your global
 environment.

 Compilation is done through ninja, **not** Visual Studio.

 ### CPU Architectures supported

 The default architecture for Windows, Linux, and Mac is "`x64`". On Windows,
 "`x86`" is also supported. GN parameter "`target_cpu = "x86"`" can be used to
 override the default value. If you specify Android build, the default CPU
 architecture will be "`arm`".

 It is expected that there are still some places lurking in the code which will
 not function properly on big-endian architectures. Bugs and/or patches are
 welcome, however providing this support is **not** a priority at this time.

 #### Google employees

 Run: `download_from_google_storage --config` and follow the
 authentication instructions. **Note that you must authenticate with your
 @google.com credentials**. Enter "0" if asked for a project-id.

 Once you've done this, the toolchain will be installed automatically for
 you in the [Generate the build files](#GenBuild) step below.

 The toolchain will be in `depot_tools\win_toolchain\vs_files\<hash>`, and windbg
 can be found in `depot_tools\win_toolchain\vs_files\<hash>\win_sdk\Debuggers`.

 If you want the IDE for debugging and editing, you will need to install
 it separately, but this is optional and not needed for building PDFium.

 ## Get the code

 The name of the top-level directory does not matter. In our examples, we use
 "repo". This directory must not have been used before by `gclient config` as
 each directory can only house a single gclient configuration.

 ```
 mkdir repo
 cd repo
 gclient config --unmanaged https://pdfium.googlesource.com/pdfium.git
 gclient sync
 cd pdfium
 ```

 Additional build dependencies need to be installed by running:

 ```
 ./build/install-build-deps.sh
 ```

 ## Generate the build files

 We use GN to generate the build files and
 [Ninja](http://martine.github.io/ninja/)
 to execute the build files.  Both of these are included with the
 depot\_tools checkout.

 ### Selecting build configuration

 PDFium may be built either with or without JavaScript support, and with
 or without XFA forms support.  Both of these features are enabled by
 default. Also note that the XFA feature requires JavaScript.

 Configuration is done by executing `gn args <directory>` to configure the build.
 This will launch an editor in which you can set the following arguments.
 A typical `<directory>` name is `out/Debug`.

 ```
 use_goma = true  # Googlers only. Make sure goma is installed and running first.
 is_debug = true  # Enable debugging features.

 pdf_use_skia = false  # Set true to enable experimental skia backend.
 pdf_use_skia_paths = false  # Set true to enable experimental skia backend (paths only).

 pdf_enable_xfa = true  # Set false to remove XFA support (implies JS support).
 pdf_enable_v8 = true  # Set false to remove Javascript support.
 pdf_is_standalone = true  # Set for a non-embedded build.
 is_component_build = false # Disable component build (must be false)

 clang_use_chrome_plugins = false  # Currently must be false.
 ```

 Note, you must set `pdf_is_standalone = true` if you want the sample
 applications like `pdfium_test` to build.

 When complete the arguments will be stored in `<directory>/args.gn`, and
 GN will automatically use the new arguments to generate build files.
 Should your files fail to generate, please double-check that you have set
 use\_sysroot as indicated above.

 ## Building the code

 You can build the sample program by running: `ninja -C <directory> pdfium_test`
 You can build the entire product (which includes a few unit tests) by running:
 `ninja -C <directory> pdfium_all`.

 ## Running the sample program

 The pdfium\_test program supports reading, parsing, and rasterizing the pages of
 a .pdf file to .ppm or .png output image files (windows supports two other
 formats). For example: `<directory>/pdfium_test --ppm path/to/myfile.pdf`. Note
 that this will write output images to `path/to/myfile.pdf.<n>.ppm`.

 ## Testing

 There are currently several test suites that can be run:

  * pdfium\_unittests
  * pdfium\_embeddertests
  * testing/tools/run\_corpus\_tests.py
  * testing/tools/run\_javascript\_tests.py
  * testing/tools/run\_pixel\_tests.py

 It is possible the tests in the `testing` directory can fail due to font
 differences on the various platforms. These tests are reliable on the bots. If
 you see failures, it can be a good idea to run the tests on the tip-of-tree
 checkout to see if the same failures appear.

 ## Code Coverage

 Code coverage reports for PDFium can be generated in Linux development
 environments. Details can be found [here](/docs/code-coverage.md).

 ## Profiling

 Valgrind and other profiling tools do not work correctly with the standard build
 setup that PDFium uses. You will need to add
 `ro_segment_workaround_for_valgrind=true` to `args.gn` to get symbols to
 correctly appear.

 ## Waterfall

 The current health of the source tree can be found at
 https://ci.chromium.org/p/pdfium/g/main/console

 ## Community

 There are several mailing lists that are setup:

  * [PDFium](https://groups.google.com/forum/#!forum/pdfium)
  * [PDFium Reviews](https://groups.google.com/forum/#!forum/pdfium-reviews)
  * [PDFium Bugs](https://groups.google.com/forum/#!forum/pdfium-bugs)

 Note, the Reviews and Bugs lists are typically read-only.

 ## Bugs

  We use this
 [bug tracker](https://code.google.com/p/pdfium/issues/list), but for security
 bugs, please use [Chromium's security bug template]
 (https://code.google.com/p/chromium/issues/entry?template=Security%20Bug)
 and add the "Cr-Internals-Plugins-PDF" label.

 ## Contributing code

 For contributing code, we will follow
 [Chromium's process](http://dev.chromium.org/developers/contributing-code)
 as much as possible. The main exceptions are:

 1. Code has to conform to the existing style and not Chromium/Google style.
 2. PDFium uses a different tool for code reviews, and credentials for
 the tool need to be generated before uploading a CL.
 3. PDFium is currently holding at C++11 compatibility, rejecting features that
 are only present in C++14 (onto which Chromium is now slowly moving).
	# PDFium

	## Prerequisites

	Get the chromium depot tools via the instructions at
	http://www.chromium.org/developers/how-tos/install-depot-tools (this provides
	the gclient utility needed below).

	Also install Python, Subversion, and Git and make sure they're in your path.


	### Windows development

	PDFium uses the same build tool as Chromium:

	#### Open source contributors
	Please refer to [Chromium's Visual Studio set up](https://chromium.googlesource.com/chromium/src/+/master/docs/windows_build_instructions.md#visual-studio)
	for requirements and instructions on build environment configuration.

	Run `set DEPOT_TOOLS_WIN_TOOLCHAIN=0`, or set that variable in your global
	environment.

	Compilation is done through ninja, not Visual Studio.

	### CPU Architectures supported

	The default architecture for Windows, Linux, and Mac is "`x64`". On Windows,
	"`x86`" is also supported. GN parameter "`target_cpu = "x86"`" can be used to
	override the default value. If you specify Android build, the default CPU
	architecture will be "`arm`".

	It is expected that there are still some places lurking in the code which will
	not function properly on big-endian architectures. Bugs and/or patches are
	welcome, however providing this support is not a priority at this time.

	#### Google employees

	Run: `download_from_google_storage --config` and follow the
	authentication instructions. **Note that you must authenticate with your
	@google.com credentials**. Enter "0" if asked for a project-id.

	Once you've done this, the toolchain will be installed automatically for
	you in the [Generate the build files](#GenBuild) step below.

	The toolchain will be in `depot_tools\win_toolchain\vs_files\<hash>`, and windbg
	can be found in `depot_tools\win_toolchain\vs_files\<hash>\win_sdk\Debuggers`.

	If you want the IDE for debugging and editing, you will need to install
	it separately, but this is optional and not needed for building PDFium.

	## Get the code

	The name of the top-level directory does not matter. In our examples, we use
	"repo". This directory must not have been used before by `gclient config` as
	each directory can only house a single gclient configuration.

	```
	mkdir repo
	cd repo
	gclient config --unmanaged https://pdfium.googlesource.com/pdfium.git
	gclient sync
	cd pdfium
	```

	Additional build dependencies need to be installed by running:

	```
	./build/install-build-deps.sh
	```

	## Generate the build files

	We use GN to generate the build files and
	[Ninja](http://martine.github.io/ninja/)
	to execute the build files. Both of these are included with the
	depot\_tools checkout.

	### Selecting build configuration

	PDFium may be built either with or without JavaScript support, and with
	or without XFA forms support. Both of these features are enabled by
	default. Also note that the XFA feature requires JavaScript.

	Configuration is done by executing `gn args <directory>` to configure the build.
	This will launch an editor in which you can set the following arguments.
	A typical `<directory>` name is `out/Debug`.

	```
	use_goma = true # Googlers only. Make sure goma is installed and running first.
	is_debug = true # Enable debugging features.

	pdf_use_skia = false # Set true to enable experimental skia backend.
	pdf_use_skia_paths = false # Set true to enable experimental skia backend (paths only).

	pdf_enable_xfa = true # Set false to remove XFA support (implies JS support).
	pdf_enable_v8 = true # Set false to remove Javascript support.
	pdf_is_standalone = true # Set for a non-embedded build.
	is_component_build = false # Disable component build (must be false)

	clang_use_chrome_plugins = false # Currently must be false.
	```

	Note, you must set `pdf_is_standalone = true` if you want the sample
	applications like `pdfium_test` to build.

	When complete the arguments will be stored in `<directory>/args.gn`, and
	GN will automatically use the new arguments to generate build files.
	Should your files fail to generate, please double-check that you have set
	use\_sysroot as indicated above.

	## Building the code

	You can build the sample program by running: `ninja -C <directory> pdfium_test`
	You can build the entire product (which includes a few unit tests) by running:
	`ninja -C <directory> pdfium_all`.

	## Running the sample program

	The pdfium\_test program supports reading, parsing, and rasterizing the pages of
	a .pdf file to .ppm or .png output image files (windows supports two other
	formats). For example: `<directory>/pdfium_test --ppm path/to/myfile.pdf`. Note
	that this will write output images to `path/to/myfile.pdf.<n>.ppm`.

	## Testing

	There are currently several test suites that can be run:

	* pdfium\_unittests
	* pdfium\_embeddertests
	* testing/tools/run\_corpus\_tests.py
	* testing/tools/run\_javascript\_tests.py
	* testing/tools/run\_pixel\_tests.py

	It is possible the tests in the `testing` directory can fail due to font
	differences on the various platforms. These tests are reliable on the bots. If
	you see failures, it can be a good idea to run the tests on the tip-of-tree
	checkout to see if the same failures appear.

	## Code Coverage

	Code coverage reports for PDFium can be generated in Linux development
	environments. Details can be found [here](/docs/code-coverage.md).

	## Profiling

	Valgrind and other profiling tools do not work correctly with the standard build
	setup that PDFium uses. You will need to add
	`ro_segment_workaround_for_valgrind=true` to `args.gn` to get symbols to
	correctly appear.

	## Waterfall

	The current health of the source tree can be found at
	https://ci.chromium.org/p/pdfium/g/main/console

	## Community

	There are several mailing lists that are setup:

	* [PDFium](https://groups.google.com/forum/#!forum/pdfium)
	* [PDFium Reviews](https://groups.google.com/forum/#!forum/pdfium-reviews)
	* [PDFium Bugs](https://groups.google.com/forum/#!forum/pdfium-bugs)

	Note, the Reviews and Bugs lists are typically read-only.

	## Bugs

	We use this
	[bug tracker](https://code.google.com/p/pdfium/issues/list), but for security
	bugs, please use [Chromium's security bug template]
	(https://code.google.com/p/chromium/issues/entry?template=Security%20Bug)
	and add the "Cr-Internals-Plugins-PDF" label.

	## Contributing code

	For contributing code, we will follow
	[Chromium's process](http://dev.chromium.org/developers/contributing-code)
	as much as possible. The main exceptions are:

	1. Code has to conform to the existing style and not Chromium/Google style.
	2. PDFium uses a different tool for code reviews, and credentials for
	the tool need to be generated before uploading a CL.
	3. PDFium is currently holding at C++11 compatibility, rejecting features that
	are only present in C++14 (onto which Chromium is now slowly moving).