f6b2baa3e8
I wished there was a way to do this in smaller steps, but with
every line fixed an error somewhere else became visible. Here
is a (probably incomplete) list of the issues:
* Only one set of parentheses was supported. This is a hard
to solve problem without a real parser (one solution is to
use an recursive RE, see below).
* The precedence order was wrong. Might have been adapted just
to give a positive result for the arbitrary state of the tree.
* Numbered match variables (e.g. $1, $2, etc.) are not local.
Calling handle_expressions() recursively once with $1, then
with $2, resulted in using the final $2 after the first
recursive call (garbage, practically).
Also, symbol and expression parsing was mixed, making things
harder to follow.
To remedy the issues:
* Split handle_symbol() out. It is called with whitespace
stripped, to keep the uglier REs in handle_expressions().
* Match balanced parentheses and quotes when splitting
expressions. In this recursive RE
/(\((?:[^\(\)]++|(?-1))*\))/
the `(?-1)` references the outer-most group, thus the whole
expression itself. So it matches a pair of parentheses with
a mix of non-parentheses and the recursive rule itself inside.
This allows us to:
* Order the expression matches according to their precedence
rules. Now we can match `<expr> '||' <expr>` first as we should
and everything else falls into its place.
* Remove the bail-out that silenced the undefined behavior.
Change-Id: Ibc1be79adc07792f0721f0dc08b50422b6da88a9
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52067
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
|
||
|---|---|---|
| 3rdparty | ||
| Documentation | ||
| LICENSES | ||
| configs | ||
| payloads | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| AUTHORS | ||
| COPYING | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README.md | ||
| gnat.adc | ||
| toolchain.inc | ||
README.md
coreboot README
coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload.
With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required.
coreboot was formerly known as LinuxBIOS.
Payloads
After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot.
See https://www.coreboot.org/Payloads for a list of supported payloads.
Supported Hardware
coreboot supports a wide range of chipsets, devices, and mainboards.
For details please consult:
Build Requirements
- make
- gcc / g++
Because Linux distribution compilers tend to use lots of patches. coreboot
does lots of "unusual" things in its build system, some of which break due
to those patches, sometimes by gcc aborting, sometimes - and that's worse -
by generating broken object code.
Two options: use our toolchain (eg. make crosstools-i386) or enable the
ANY_TOOLCHAINKconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- doxygen (for generating/viewing documentation)
- gdb (for better debugging facilities on some targets)
- ncurses (for
make menuconfigandmake nconfig) - flex and bison (for regenerating parsers)
Building coreboot
Please consult https://www.coreboot.org/Build_HOWTO for details.
Testing coreboot Without Modifying Your Hardware
If you want to test coreboot without any risks before you really decide to use it on your hardware, you can use the QEMU system emulator to run coreboot virtually in QEMU.
Please see https://www.coreboot.org/QEMU for details.
Website and Mailing List
Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website:
You can contact us directly on the coreboot mailing list:
https://www.coreboot.org/Mailinglist
Copyright and License
The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details.
coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details.
This makes the resulting coreboot images licensed under the GPL, version 2.