Commit graph

110 commits

Author SHA1 Message Date
Justine Tunney
60cb435cb4
Implement pthread_atfork()
If threads are being used, then fork() will now acquire and release and
runtime locks so that fork() may be safely used from threads. This also
makes vfork() thread safe, because pthread mutexes will do nothing when
the process is a child of vfork(). More torture tests have been written
to confirm this all works like a charm. Additionally:

- Invent hexpcpy() api
- Rename nsync_malloc_() to kmalloc()
- Complete posix named semaphore implementation
- Make pthread_create() asynchronous signal safe
- Add rm, rmdir, and touch to command interpreter builtins
- Invent sigisprecious() and modify sigset functions to use it
- Add unit tests for posix_spawn() attributes and fix its bugs

One unresolved problem is the reclaiming of *NSYNC waiter memory in the
forked child processes, within apps which have threads waiting on locks
2022-10-16 12:25:13 -07:00
Justine Tunney
f52f65b2e3
Make system() and popen() thread safe 2022-10-13 15:54:05 -07:00
Justine Tunney
e557058ac8
Improve cosmo's conformance to libc-test
This change addresses various open source compatibility issues, so that
we pass 313/411 of the tests in https://github.com/jart/libc-test where
earlier today we were passing about 30/411 of them, due to header toil.
Please note that Glibc only passes 341/411 so 313 today is pretty good!

- Make the conformance of libc/isystem/ headers nearly perfect
- Import more of the remaining math library routines from Musl
- Fix inconsistencies with type signatures of calls like umask
- Write tests for getpriority/setpriority which work great now
- conform to `struct sockaddr *` on remaining socket functions
- Import a bunch of uninteresting stdlib functions e.g. rand48
- Introduce readdir_r, scandir, pthread_kill, sigsetjmp, etc..

Follow the instructions in our `tool/scripts/cosmocc` toolchain to run
these tests yourself. You use `make CC=cosmocc` on the test repository
2022-10-10 17:52:41 -07:00
Justine Tunney
7ae556463a
Rename rand64() to _rand64() 2022-10-10 04:12:06 -07:00
Justine Tunney
d5910e2673
Fix bugs and make code tinier
- Fixed bug where stdio eof wasn't being sticky
- Fixed bug where fseeko() wasn't clearing eof state
- Removed assert() usage from libc favoring _unassert() / _npassert()
2022-10-09 23:21:34 -07:00
Justine Tunney
6f7d0cb1c3
Pay off more technical debt
This makes breaking changes to add underscores to many non-standard
function names provided by the c library. MODE=tiny is now tinier and
we now use smaller locks that are better for tiny apps in this mode.
Some headers have been renamed to be in the same folder as the build
package, so it'll be easier to know which build dependency is needed.
Certain old misguided interfaces have been removed. Intel intrinsics
headers are now listed in libc/isystem (but not in the amalgamation)
to help further improve open source compatibility. Header complexity
has also been reduced. Lastly, more shell scripts are now available.
2022-09-12 23:36:56 -07:00
Justine Tunney
b5cb71ab84
Use *NSYNC for POSIX threads locking APIs
Condition variables, barriers, and r/w locks now work very well.
2022-09-11 11:04:50 -07:00
Justine Tunney
155b378a39
Tidy up the threading implementation
The organization of the source files is now much more rational.
Old experiments that didn't work out are now deleted. Naming of
things like files is now more intuitive.
2022-09-10 02:56:25 -07:00
Justine Tunney
7ff0ea8c13
Make pthread mutexes more scalable
pthread_mutex_lock() now uses a better algorithm which goes much faster
in multithreaded environments that have lock contention. This comes at
the cost of adding some fixed-cost overhead to mutex invocations. That
doesn't matter for Cosmopolitan because our core libraries all encode
locking operations as NOP instructions when in single-threaded mode.
Overhead only applies starting the moment you first call clone().
2022-09-05 15:57:51 -07:00
Justine Tunney
83d41e4588 Clean up some code 2022-08-20 12:32:51 -07:00
Justine Tunney
6c0bbfac4a Fix some bugs 2022-08-14 13:28:07 -07:00
Justine Tunney
8a0a2c0c36 Fold LIBC_RAND into LIBC_STDIO/TINYMATH/INTRIN 2022-08-11 12:32:00 -07:00
Justine Tunney
05b8f82371 Fold LIBC_BITS into LIBC_INTRIN 2022-08-11 12:13:18 -07:00
Justine Tunney
10fd8bdb70 Unbloat the build
This change resurrects ae5d06dc53
2022-08-11 00:15:29 -07:00
Justine Tunney
7b993d561c Use private keyword on makefile target variables 2022-08-10 18:36:11 -07:00
Justine Tunney
c1d99676c4 Revert "Unbloat build config"
This reverts commit ae5d06dc53.
2022-08-10 12:44:56 -07:00
Justine Tunney
ae5d06dc53 Unbloat build config
- 10.5% reduction of o//depend dependency graph
- 8.8% reduction in latency of make command
- Fix issue with temporary file cleanup

There's a new -w option in compile.com that turns off the recent
Landlock output path workaround for "good commands" which do not
unlink() the output file like GNU tooling does.

Our new GNU Make unveil sandboxing appears to have zero overhead
in the grand scheme of things. Full builds are pretty fast since
the only thing that's actually slowed us down is probably libcxx

    make -j16 MODE=rel
    RL: took 85,732,063µs wall time
    RL: ballooned to 323,612kb in size
    RL: needed 828,560,521µs cpu (11% kernel)
    RL: caused 39,080,670 page faults (99% memcpy)
    RL: 350,073 context switches (72% consensual)
    RL: performed 0 reads and 11,494,960 write i/o operations

pledge() and unveil() no longer consider ENOSYS to be an error.
These functions have also been added to Python's cosmo module.

This change also removes some WIN32 APIs and System Five magnums
which we're not using and it's doubtful anyone else would be too
2022-08-10 04:43:09 -07:00
Justine Tunney
69f4152f38 Always initialize thread local storage
We had previously not enabled TLS in MODE=tiny in order to keep the
smallest example programs (e.g. life.com) just 16kb in size. But it
was error prone doing that, so now we just always enable it because
this change uses hacks to ensure it won't increase life.com's size.

This change also fixes a bug on NetBSD, where signal handlers would
break thread local storage if SA_SIGINFO was being used. This looks
like it might be a bug in NetBSD, but it's got a simple workaround.
2022-07-19 00:21:46 -07:00
Justine Tunney
4f4889ddf7 Use futexes on OpenBSD and improve threading 2022-07-17 19:59:49 -07:00
Justine Tunney
8cdec62f5b Apply even more fixups
- Finish cleaning up the stdio unlocked APIs
- Make __cxa_finalize() properly thread safe
- Don't log locks if threads aren't being used
- Add some more mutex guards to places using _mmi
- Specific lock names now appear in the --ftrace logs
- Fix mkdeps.com generating invalid Makefiles sometimes
- Simplify and fix bugs in the test runner infrastructure
- Fix issue where sometimes some functions wouldn't be logged
2022-06-12 11:57:00 -07:00
Justine Tunney
29af890efa Disable malloc mutex when not using threads 2022-06-11 19:18:09 -07:00
Justine Tunney
a41669dec6 Make dlmalloc a little faster
This change also documents the libc arena allocator.
2022-06-09 21:25:21 -07:00
Justine Tunney
fa1e8a3e65 Make emacs not croak when editing dlmalloc 2022-06-09 17:45:30 -07:00
Justine Tunney
ec2cb88058 Make fixes and improvements
- Document more compiler flags
- Expose new __print_maps() api
- Better overflow checking in mmap()
- Improve the shell example somewhat
- Fix minor runtime bugs regarding stacks
- Make kill() on fork()+execve()'d children work
- Support CLONE_CHILD_CLEARTID for proper joining
- Fix recent possible deadlock regression with --ftrace
2022-05-19 16:57:49 -07:00
Justine Tunney
9208c83f7a Make some systemic improvements
- add vdso dump utility
- tests now log stack usage
- rename g_ftrace to __ftrace
- make internal spinlocks go faster
- add conformant c11 atomics library
- function tracing now logs stack usage
- make function call tracing thread safe
- add -X unsecure (no ssl) mode to redbean
- munmap() has more consistent behavior now
- pacify fsync() calls on python unit tests
- make --strace flag work better in redbean
- start minimizing and documenting compiler flags
2022-05-18 16:52:36 -07:00
Justine Tunney
ce71677156 Improve threading support further 2022-05-17 04:14:28 -07:00
Justine Tunney
7aafa64ab3 Make improvements
- Bump redbean up to 2.0
- Trim down the MODE=tiny build a bit
- Add Indian Standard Time to zoneinfo
2022-04-29 00:42:47 -07:00
Justine Tunney
2f56ebfe78 Do code cleanup use duff device linenoise i/o 2022-04-22 18:56:52 -07:00
Justine Tunney
933411ba99 Improve synchronization
- Fix bugs in kDos2Errno definition
- malloc() should now be thread safe
- Fix bug in rollup.com header generator
- Fix open(O_APPEND) on the New Technology
- Fix select() on the New Technology and test it
- Work towards refactoring i/o for thread safety
- Socket reads and writes on NT now poll for signals
- Work towards i/o completion ports on the New Technology
- Make read() and write() intermittently check for signals
- Blinkenlights keyboard i/o so much better on NT w/ poll()
- You can now poll() files and sockets at the same time on NT
- Fix bug in appendr() that manifests with dlmalloc footers off
2022-04-15 15:31:55 -07:00
Justine Tunney
f684e348d4 Improve signals and memory protection
- Document sigaction()
- Simplify New Technology fork() code
- Testing and many bug fixes for mprotect()
- Distribute Intel Xed ILD in the amalgamation
- Turn Xed enums into defines to avoid DWARF bloat
- Improve polyfilling of SA_SIGINFO on BSDs and fix bugs
- setpgid(getpid(), getpid()) on Windows will ignore CTRL-C
- Work around issues relating to NT mappings being executable
- Permit automatic executable stack override via `ape_stack_pf`
2022-04-12 22:11:00 -07:00
Justine Tunney
868af3f950 Import C++ Standard Template Library
You can now use the hardest fastest and most dangerous language there is
with Cosmopolitan. So far about 75% of LLVM libcxx has been added. A few
breaking changes needed to be made to help this go smoothly.

- Rename nothrow to dontthrow
- Rename nodiscard to dontdiscard
- Add some libm functions, e.g. lgamma, nan, etc.
- Change intmax_t from int128 to int64 like everything else
- Introduce %jjd formatting directive for int128_t
- Introduce strtoi128(), strtou128(), etc.
- Rename bsrmax() to bsr128()

Some of the templates that should be working currently are std::vector,
std::string, std::map, std::set, std::deque, etc.
2022-03-22 06:41:54 -07:00
Justine Tunney
6c2fd9ecc6 Clean old .source directive out of asm code 2022-03-18 12:43:21 -07:00
Gautham
6f658f058b
Change noinline to dontinline (#312)
We defined `noinline` as an abbreviation for the longer version
`__attribute__((__noinline__))` which caused name clashes since
third party codebases often write it as `__attribute__((noinline))`.
2021-11-12 15:12:18 -08:00
Justine Tunney
226aaf3547 Improve memory safety
This commit makes numerous refinements to cosmopolitan memory handling.

The default stack size has been reduced from 2mb to 128kb. A new macro
is now provided so you can easily reconfigure the stack size to be any
value you want. Work around the breaking change by adding to your main:

    STATIC_STACK_SIZE(0x00200000);  // 2mb stack

If you're not sure how much stack you need, then you can use:

    STATIC_YOINK("stack_usage_logging");

After which you can `sort -nr o/$MODE/stack.log`. Based on the unit test
suite, nothing in the Cosmopolitan repository (except for Python) needs
a stack size greater than 30kb. There are also new macros for detecting
the size and address of the stack at runtime, e.g. GetStackAddr(). We
also now support sigaltstack() so if you want to see nice looking crash
reports whenever a stack overflow happens, you can put this in main():

    ShowCrashReports();

Under `make MODE=dbg` and `make MODE=asan` the unit testing framework
will now automatically print backtraces of memory allocations when
things like memory leaks happen. Bugs are now fixed in ASAN global
variable overrun detection. The memtrack and asan runtimes also handle
edge cases now. The new tools helped to identify a few memory leaks,
which are fixed by this change.

This change should fix an issue reported in #288 with ARG_MAX limits.
Fixing this doubled the performance of MKDEPS.COM and AR.COM yet again.
2021-10-13 17:27:13 -07:00
Justine Tunney
7061c79c22 Make fixes, improvements, and chibicc python bindings
- python now mixes audio 10x faster
- python octal notation is restored
- chibicc now builds code 3x faster
- chibicc now has help documentation
- chibicc can now generate basic python bindings
- linenoise now supports some paredit-like features

See #141
2021-10-08 08:41:57 -07:00
Justine Tunney
39bf41f4eb Make numerous improvements
- Python static hello world now 1.8mb
- Python static fully loaded now 10mb
- Python HTTPS client now uses MbedTLS
- Python REPL now completes import stmts
- Increase stack size for Python for now
- Begin synthesizing posixpath and ntpath
- Restore Python \N{UNICODE NAME} support
- Restore Python NFKD symbol normalization
- Add optimized code path for Intel SHA-NI
- Get more Python unit tests passing faster
- Get Python help() pagination working on NT
- Python hashlib now supports MbedTLS PBKDF2
- Make memcpy/memmove/memcmp/bcmp/etc. faster
- Add Mersenne Twister and Vigna to LIBC_RAND
- Provide privileged __printf() for error code
- Fix zipos opendir() so that it reports ENOTDIR
- Add basic chmod() implementation for Windows NT
- Add Cosmo's best functions to Python cosmo module
- Pin function trace indent depth to that of caller
- Show memory diagram on invalid access in MODE=dbg
- Differentiate stack overflow on crash in MODE=dbg
- Add stb_truetype and tools for analyzing font files
- Upgrade to UNICODE 13 and reduce its binary footprint
- COMPILE.COM now logs resource usage of build commands
- Start implementing basic poll() support on bare metal
- Set getauxval(AT_EXECFN) to GetModuleFileName() on NT
- Add descriptions to strerror() in non-TINY build modes
- Add COUNTBRANCH() macro to help with micro-optimizations
- Make error / backtrace / asan / memory code more unbreakable
- Add fast perfect C implementation of μ-Law and a-Law audio codecs
- Make strtol() functions consistent with other libc implementations
- Improve Linenoise implementation (see also github.com/jart/bestline)
- COMPILE.COM now suppresses stdout/stderr of successful build commands
2021-09-28 01:52:34 -07:00
Justine Tunney
ed485391da Reduce memory needed by ASAN morgue 2021-08-19 09:34:24 -07:00
Justine Tunney
398f0c16fb Add SNI support to redbean and improve SSL perf
This change makes SSL virtual hosting possible. You can now load
multiple certificates for multiple domains and redbean will just
figure out which one to use, even if you only have 1 ip address.
You can also use a jumbo certificate that lists all your domains
in the the subject alternative names.

This change also makes performance improvements to MbedTLS. Here
are some benchmarks vs. cc1920749e

                                   BEFORE    AFTER   (microsecs)
suite_ssl.com                     2512881   191738 13.11x faster
suite_pkparse.com                   36291     3295 11.01x faster
suite_x509parse.com                854669   120293  7.10x faster
suite_pkwrite.com                    6549     1265  5.18x faster
suite_ecdsa.com                     53347    18778  2.84x faster
suite_pk.com                        49051    18717  2.62x faster
suite_ecdh.com                      19535     9502  2.06x faster
suite_shax.com                      15848     7965  1.99x faster
suite_rsa.com                      353257   184828  1.91x faster
suite_x509write.com                162646    85733  1.90x faster
suite_ecp.com                       20503    11050  1.86x faster
suite_hmac_drbg.no_reseed.com       19528    11417  1.71x faster
suite_hmac_drbg.nopr.com            12460     8010  1.56x faster
suite_mpi.com                      687124   442661  1.55x faster
suite_hmac_drbg.pr.com              11890     7752  1.53x faster

There aren't any special tricks to the performance imporvements.
It's mostly due to code cleanup, assembly and intel instructions
like mulx, adox, and adcx.
2021-07-23 13:56:13 -07:00
Justine Tunney
8c4cce043c Make improvements to redbean
The following Lua APIs have been added:

  - IsDaemon() → bool
  - ProgramPidPath(str)

The following Lua hooks have been added:

  - OnClientConnection(ip:int,port:int,serverip:int,serverport:int) → bool
  - OnProcessCreate(pid:int,ip:int,port:int,serverip:int,serverport:int)
  - OnProcessDestroy(pid:int)
  - OnServerStart()
  - OnServerStop()
  - OnWorkerStart()
  - OnWorkerStop()

redbean now does a better job at applying gzip on the fly from the local
filesystem, using a streaming chunked api with constant memory, which is
useful for doing things like serving a 4gb text file off NFS, and having
it start transmitting in milliseconds. redbean will also compute entropy
on the beginnings of files to determine if compression is profitable.

This change pays off technical debts relating to memory, such as relying
on exit() to free() allocations. That's now mostly fixed so it should be
easier now to spot memory leaks in malloc traces.

This change also fixes bugs and makes improvements to our SSL support.
Uniprocess mode failed handshakes are no longer an issue. Token Alpn is
offered so curl -v looks less weird. Hybrid SSL certificate loading is
now smarter about naming conflicts. Self-signed CA root anchors will no
longer be delivered to the client during the handshake.
2021-07-10 15:19:37 -07:00
Justine Tunney
4effa23528 Make more major improvements to redbean
- POSIX regular expressions for Lua
- Improved protocol parsing and encoding
- Additional APIs for ZIP storage retrieval
- Fix st_mode issue on NT for regular files
- Generalized APIs for URL and Host handling
- Worked out the kinks in resource resolution
- Allow for custom error pages like /404.html
2021-04-20 19:14:21 -07:00
Justine Tunney
bf03b2e64c Make major improvements to redbean and libraries
The most exciting improvement is dynamic pages will soon be able to use
the executable itself as an object store. it required a heroic technique
for overcoming ETXTBSY restrictions which lets us open the executable in
read/write mode, which means (1) wa can restore the APE header, and (2)
we can potentially containerize redbean extension code so that modules
you download for your redbean online will only impact your redbean.

Here's a list of breaking changes to redbean:

- Remove /tool/net/ prefix from magic ZIP paths
- GetHeader() now returns NIL if header is absent

Here's a list of fixes and enhancements to redbean:

- Support 64-bit ZIP archives
- Record User-Agent header in logs
- Add twelve error handlers to accept()
- Display octal st_mode on listing page
- Show ZIP file comments on listing page
- Restore APE MZ header on redbean startup
- Track request count on redbean index page
- Report server uptime on redbean index page
- Don't bind server socket using SO_REUSEPORT
- Fix #151 where Lua LoadAsset() could free twice
- Report rusage accounting when workers exit w/ -vv
- Use ZIP iattr field as text/plain vs. binary hint
- Add ParseUrl() API for parsing things like a.href
- Add ParseParams() API for parsing HTTP POST bodies
- Add IsAcceptablePath() API for checking dots, etc.
- Add IsValidHttpToken() API for validating sane ASCII
- Add IsAcceptableHostPort() for validating HOST[:PORT]
- Send 400 response to HTTP/1.1 requests without a Host
- Send 403 response if ZIP or file isn't other readable
- Add virtual hosting that tries prepending Host to path
- Route requests based on Host in Request-URI if present
- Host routing will attempt to remove or add the www. prefix
- Sign-extend UNIX timestamps and don't adjust FileTime zone

Here's some of the improvements made to Cosmopolitan Libc:

- Fix ape.S indentation
- Improve consts.sh magnums
- Write pretty good URL parser
- Improve rusage accounting apis
- Bring mremap() closer to working
- Added ZIP APIs which will change
- Check for overflow in reallocarray()
- Remove overly fancy linkage in strerror()
- Fix GDB attach on crash w/ OpenBSD msyscall()
- Make sigqueue() portable to most UNIX distros
- Make integer serialization macros more elegant
- Bring back 34x tprecode8to16() performance boost
- Make malloc() more resilient to absurdly large sizes
2021-04-18 12:34:15 -07:00
Justine Tunney
d932948fb4 Remove more nonstandard stuff from cosmopolitan.h
Fixes #61
2021-03-01 00:18:23 -08:00
Justine Tunney
e75ffde09e Get codebase completely working with LLVM
You can now build Cosmopolitan with Clang:

    make -j8 MODE=llvm
    o/llvm/examples/hello.com

The assembler and linker code is now friendly to LLVM too.
So it's not needed to configure Clang to use binutils under
the hood. If you love LLVM then you can now use pure LLVM.
2021-02-09 02:57:32 -08:00
Justine Tunney
0e36cb3ac4 Improve dead code elimination 2021-02-08 04:04:42 -08:00
Justine Tunney
a37960a3af Remove dollars from system call support symbols 2021-02-03 19:35:29 -08:00
Justine Tunney
1ff9ab95ac Make C memory safe like Rust
This change enables Address Sanitizer systemically w/ `make MODE=dbg`.
Our version of Rust's `unsafe` keyword is named `noasan` which is used
for two functions that do aligned memory chunking, like `strcpy.c` and
we need to fix the tiny DEFLATE code, but that's it everything else is
fabulous you can have all the fischer price security blankets you need

Best of all is we're now able to use the ASAN data in Blinkenlights to
colorize the memory dumps. See the screenshot below of a test program:

  https://justine.lol/blinkenlights/asan.png

Which is operating on float arrays stored on the stack, with red areas
indicating poisoned memory, and the green areas indicate valid memory.
2021-02-01 03:58:46 -08:00
Justine Tunney
9f68d6eee9 Fix link order in cosmopolitan.a
It turned out that the linker was doing the wrong with the amalgamation
library concerning weak stubs. A regression test has been added and new
binaries have been uploaded to https://justine.lol/cosmopolitan/

Ideally this should be fixed by building a tool that turns multiple .a
files into a single .a file with deduplication. As a workaround for now
the cosmopolitan.a build is restructured to not include LIBC_STUBS which
meant technical debt needed to be paid off where non-stub interfaces
were moved to LIBC_INTRIN and LIBC_NEXGEN32E.

Thank @PerfectProductions in #31 for the report!
2021-01-16 12:05:41 -08:00
Justine Tunney
37a4c70c36 Change license 2020-12-27 17:18:44 -08:00
Justine Tunney
1bc3a25505 Improve documentation
The Cosmo API documentation page is pretty good now
https://justine.lol/cosmopolitan/documentation.html
2020-12-27 07:02:35 -08:00
Justine Tunney
13437dd19b Auto-generate some documentation 2020-12-26 02:09:07 -08:00
Justine Tunney
830334d767 Hunt down some small bugs 2020-12-24 16:01:48 -08:00
Justine Tunney
1fc91f3580 Fold conv package into fmt
Both packages had nearly identical dependency requirements, so merging
them should help reduce the complexity of the build graph.
2020-12-09 16:52:00 -08:00
Justine Tunney
8da931a7f6 Add chibicc
This program popped up on Hacker News recently. It's the only modern
compiler I've ever seen that doesn't have dependencies and is easily
modified. So I added all of the missing GNU extensions I like to use
which means it might be possible soon to build on non-Linux and have
third party not vendor gcc binaries.
2020-12-06 16:20:21 -08:00
Justine Tunney
ea0b5d9d1c Get Cosmopolitan into releasable state
A new rollup tool now exists for flattening out the headers in a way
that works better for our purposes than cpp. A lot of the API clutter
has been removed. APIs that aren't a sure thing in terms of general
recommendation are now marked internal.

There's now a smoke test for the amalgamation archive and gigantic
header file. So we can now guarantee you can use this project on the
easiest difficulty setting without the gigantic repository.

A website is being created, which is currently a work in progress:
https://justine.storage.googleapis.com/cosmopolitan/index.html
2020-11-25 08:19:00 -08:00
Justine Tunney
feed0d2b0e Add minor improvements and cleanup 2020-10-27 03:39:46 -07:00
Justine Tunney
416fd86676 Make improvements
- Emulator can now test the αcτµαlly pδrταblε εxεcµταblε bootloader

- Whipped up a webserver named redbean. It services 150k requests per
  second on a single core. Bundling assets inside zip enables extremely
  fast serving for two reasons. The first is that zip central directory
  lookups go faster than stat() system calls. The second is that both
  zip and gzip content-encoding use DEFLATE, therefore, compressed
  responses can be served via the sendfile() system call which does an
  in-kernel copy directly from the zip executable structure. Also note
  that red bean zip executables can be deployed easily to all platforms,
  since these native executables work on Linux, Mac, BSD, and Windows.

- Address sanitizer now works very well
2020-09-14 00:02:34 -07:00
Justine Tunney
7327c345f9 Get address sanitizer mostly working 2020-09-03 05:44:37 -07:00
Justine Tunney
f4f4caab0e Add x86_64-linux-gnu emulator
I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.

https://justine.storage.googleapis.com/emulator625.mp4
2020-08-25 04:43:42 -07:00
Justine Tunney
ac00be1a4e Make small fixes and oops ran clang-format on dtoa 2020-06-30 19:55:47 -07:00
Justine Tunney
c91b3c5006 Initial import 2020-06-15 07:18:57 -07:00