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4 commits

Author SHA1 Message Date
Justine Tunney
1831e3ccf7 Bring life.com executable size back down to 12kb 2021-03-02 01:13:32 -08:00
Justine Tunney
d932948fb4 Remove more nonstandard stuff from cosmopolitan.h
Fixes #61
2021-03-01 00:18:23 -08:00
Justine Tunney
94afa982c3 Fix zip executables on MacOS
Here's why we got those `Killed: 11` failures on MacOS after modifying
the contentns of the redbean.com executable. If you were inserting a
small file, such as a HelloWorld.html file, then InfoZIP might have
decreased the size of the executable to less than what the Mach-O
section had been expecting.

That's because when zipobj.com put things like time zone data in the
executable, it aligned each zip file entry on a 64-byte boundary, simply
for the sake of readability in binary dumps. But when InfoZIP edited the
file it would rewrite every entry using ZIP's usual 2-byte alignment.
Thus causing shrinkage.

The solution was to reconfigure the linker script so that zip file bits
that get put into the executable at link-time, such as timezone data,
aren't officially part of the executable image, i.e. we don't want the
operating system to load that part.

The original decision to put the linked zip files into the .data section
was mostly made so that when the executable was run in its .com.dbg form
it would still have the zip entries be accessible, even though there was
tons of GNU debug data following the central directory. We're not going
to be able to do that. The .com executable should be the canonical
executable. We have really good tools for automatically attaching and
configuring GDB correctly with debug symbols even when the .com is run.
We'll have to rely on those in cases where zip embedding is used.

See #53
See #54
See #68
2021-02-27 18:16:59 -08:00
Justine Tunney
edd9297eba Support malloc() on bare metal
Your Actually Portable Executables now contains a simple virtual memory
that works similarly to the Linux Kernel in the sense that it maps your
physical memory to negative addresses. This is needed to support mmap()
and malloc(). This functionality has zero code size impact. For example
the MODE=tiny LIFE.COM executable is still only 12KB in size.

The APE bootloader code has also been simplified to improve readibility
and further elevate the elegance by which we're able to support so many
platforms thereby enhancing verifiability so that we may engender trust
in this bootloading process.
2021-02-24 00:53:24 -08:00
Renamed from ape/lib/apm.h (Browse further)