Add /* FALLTHROUGH */ comment for sure.

Add an option (LIBSA_CREAD_NOCRC) to disable gunzip CRC32 calculation.

No obvious sideeffect on booting i386 GENERIC kernels (without the option).
Closes PR/50638 (Extreme slowness on loading gzipped kernels on old CPUs).

white space -> tab.

branches: 1.26.6;
Let's not use uninitialized variables to write to random memory
locations, shall we?

Rework previous (1.24) change. Rather than depending on the
file's flags to decide if decompress cleanup is needed, just
check to see if the open() allocated the 'struct sd *' used for
decompression.

This fixes recent problem where presence of a "load=ffs" command
in my /boot.cfg resulted in a "heap full" error at boot time.

OK martin@

branches: 1.24.4;
Make the check in close() for a non-deflatable file mode symetric to
the one in open().
Avoids dealloc() calls on NULL.

branches: 1.23.12; 1.23.22;
Fix build problems caused by crc32 addition to libkern. Also, this makes
the i386 bootblocks about 2K smaller than they were before we monkeyed
with crc32 at all.

branches: 1.22.2;
Remove __P().

branches: 1.21.4; 1.21.12; 1.21.14; 1.21.20;
- use mem* instead of b* routines, and kill the b* routines.
- use the mem* routines from libc.
XXX: There will be some lossage, but I am fixing it.

branches: 1.20.14;
unsigned -> unsigned int

style, indent, and ANSI-fy.

branches: 1.18.42; 1.18.44; 1.18.50;
free -> dealloc

Don't include zlib.h directly; redirect through libz.h; this mirrors how
libkern is done and let's us abstract where the real zlib.h is kept.

branches: 1.16.2;
merge ktrace-lwp.

branches: 1.15.16;
remove license clauses 3 and 4 from my cpoyright notices

branches: 1.14.2;
Move some stuff into .rodata.

Fix tyop in comment.

cosmetics: remove double semicolon, whitespace

Backout my libsa changes.

Update for the improvements to libsa, and don't reference libkern.h.

branches: 1.9.8; 1.9.10; 1.9.14;
Make a bunch of backward-compatible changes to the boot blocks which allow
size to be reduced substantially. (backward compatibility verified
by compiling one of the alpha boot blocks which uses all of the code
before and after, diffing the object files, and manually verifying that
the differences were 'correct'. some differences were "unavoidable,"
it wanting to avoid a double-commit, because e.g. local variables which
were previously used were no longer used.) a README which describes
supported options (or at least the ones mentioned below) is forthcoming.

add support for the preprocessor macro LIBSA_NO_TWIDDLE, which
causes calls to twiddle() to be omitted if it's defined.
add support for the preprocessor macros:
LIBSA_NO_FS_CLOSE
LIBSA_NO_FS_WRITE
LIBSA_NO_FS_SEEK
which, if defined, cause the corresponding file system operations
in the individual file system implementations to be omitted. (note
that all of those macros are not supported by all file systems at
this point. comments were added to individual file system files
to indicate lack of support, and should be cleaned up later. Backward
compatibility options e.g. UFS_NOCLOSE, etc., are supported.)
add support for the preprocessor macro LIBSA_NO_FS_SYMLINK, which
removes support for symbolic links from the file system support
functions. (same notes as for the macros above apply.)
add support for the preprocessor macro LIBSA_FS_SINGLECOMPONENT which
removes all subdirectory and symlink support from the file system
support functions. (same notes as for the macros above apply.)
add support for the preprocessor macro LIBSA_NO_FD_CHECKING, which
causes code relating to libsa file descriptor checks (e.g. range
checking and checking that a file descriptor is valid) to be
omitted if it's defined.
add support for the preprocessor macro LIBSA_NO_RAW_ACCESS, which
causes code relating to raw device access to be omitted if it's
defined.
change some structure copies to use bcopy() instead. that way
use of bcopy vs. memcpy() can easily be selected by
LIBSA_USE_MEMCPY. (without changes like these, you could end up
having both bcopy() and memcpy() included. eventually, all
calls to bcopy should be changed to calls to memcpy() or memmove()
as appropriate -- hopefully never the latter -- with an option to
use bcopy instead.)
add support for the preprocessor macro LIBSA_NO_DISKLABEL_MSGS, which
causes disklabel() to return '1' as msg rather than a string. Can
be used if the boot blocks don't care about the string, and need to
save the space.
add support for the preprocessor macro LIBSA_SINGLE_FILESYSTEM, which
if defined causes all of the file system switch code to be removed.
Its value should be the name of the file system supported by the
boot block, e.g. "ufs" for the FFS file system. calls to the
file system functions open, close, etc., which were previously
done through a function switch are then done via direct invocation
of <fs>_open, <fs>_close, etc. (e.g. ufs_open, ...).
add support for the preprocessor macro LIBSA_SINGLE_DEVICE, which
does the equivalent of LIBSA_SINGLE_FILESYSTEM but for the device
switch table. Device entry pointes are expected to be named
<dev>foo, e.g. the 'strategy' routine used when LIBSA_SINGLE_DEVICE
is set to 'disk' is diskstrategy.
make ufs.c f_nindir array be unsigned ints. the fact that it was signed
caused ufs.c to require signed division routines (which were otherwise
unnecessary for a small boot block).

That got broken in KNFifying.

Add missing prototypes and KNF the lot.

Change sd.transparent to sd.compressed, so that we default to non-
compressed mode when we zero out the structure. Check_header() now
does not force us to uncompressed mode if we read no data (EOF);
it leaves the default, so that if we check at the end of a file,
we don't set the file to uncompressed mode and blow up later lseeks
on it.

Catch errors from underlying reads, ie where oread() returns -1.
(Original code used fread() which never returns -1, so this case was
not handled.)

Avoid user space headers for standalone programs.
Don't use sys/lib/libkern or sys/lib/libz if not standalone
(ie, user space test programs).

Bring prototypes into scope.

In close(), if the file descriptor was used for writing, don't free
data structures that weren't allocated. Fix sanity-checked
by Matthias Drochner.

code to open/close/read/lseek gzipped files, from Matthias Drochner.

Add an option (LIBSA_CREAD_NOCRC) to disable gunzip CRC32 calculation.

No obvious sideeffect on booting i386 GENERIC kernels (without the option).
Closes PR/50638 (Extreme slowness on loading gzipped kernels on old CPUs).

white space -> tab.

branches: 1.26.6;
Let's not use uninitialized variables to write to random memory
locations, shall we?

Rework previous (1.24) change. Rather than depending on the
file's flags to decide if decompress cleanup is needed, just
check to see if the open() allocated the 'struct sd *' used for
decompression.

This fixes recent problem where presence of a "load=ffs" command
in my /boot.cfg resulted in a "heap full" error at boot time.

OK martin@

branches: 1.24.4;
Make the check in close() for a non-deflatable file mode symetric to
the one in open().
Avoids dealloc() calls on NULL.

branches: 1.23.12; 1.23.22;
Fix build problems caused by crc32 addition to libkern. Also, this makes
the i386 bootblocks about 2K smaller than they were before we monkeyed
with crc32 at all.

branches: 1.22.2;
Remove __P().

branches: 1.21.4; 1.21.12; 1.21.14; 1.21.20;
- use mem* instead of b* routines, and kill the b* routines.
- use the mem* routines from libc.
XXX: There will be some lossage, but I am fixing it.

branches: 1.20.14;
unsigned -> unsigned int

style, indent, and ANSI-fy.

branches: 1.18.42; 1.18.44; 1.18.50;
free -> dealloc

Don't include zlib.h directly; redirect through libz.h; this mirrors how
libkern is done and let's us abstract where the real zlib.h is kept.

branches: 1.16.2;
merge ktrace-lwp.

branches: 1.15.16;
remove license clauses 3 and 4 from my cpoyright notices

branches: 1.14.2;
Move some stuff into .rodata.

Fix tyop in comment.

cosmetics: remove double semicolon, whitespace

Backout my libsa changes.

Update for the improvements to libsa, and don't reference libkern.h.

branches: 1.9.8; 1.9.10; 1.9.14;
Make a bunch of backward-compatible changes to the boot blocks which allow
size to be reduced substantially. (backward compatibility verified
by compiling one of the alpha boot blocks which uses all of the code
before and after, diffing the object files, and manually verifying that
the differences were 'correct'. some differences were "unavoidable,"
it wanting to avoid a double-commit, because e.g. local variables which
were previously used were no longer used.) a README which describes
supported options (or at least the ones mentioned below) is forthcoming.

add support for the preprocessor macro LIBSA_NO_TWIDDLE, which
causes calls to twiddle() to be omitted if it's defined.
add support for the preprocessor macros:
LIBSA_NO_FS_CLOSE
LIBSA_NO_FS_WRITE
LIBSA_NO_FS_SEEK
which, if defined, cause the corresponding file system operations
in the individual file system implementations to be omitted. (note
that all of those macros are not supported by all file systems at
this point. comments were added to individual file system files
to indicate lack of support, and should be cleaned up later. Backward
compatibility options e.g. UFS_NOCLOSE, etc., are supported.)
add support for the preprocessor macro LIBSA_NO_FS_SYMLINK, which
removes support for symbolic links from the file system support
functions. (same notes as for the macros above apply.)
add support for the preprocessor macro LIBSA_FS_SINGLECOMPONENT which
removes all subdirectory and symlink support from the file system
support functions. (same notes as for the macros above apply.)
add support for the preprocessor macro LIBSA_NO_FD_CHECKING, which
causes code relating to libsa file descriptor checks (e.g. range
checking and checking that a file descriptor is valid) to be
omitted if it's defined.
add support for the preprocessor macro LIBSA_NO_RAW_ACCESS, which
causes code relating to raw device access to be omitted if it's
defined.
change some structure copies to use bcopy() instead. that way
use of bcopy vs. memcpy() can easily be selected by
LIBSA_USE_MEMCPY. (without changes like these, you could end up
having both bcopy() and memcpy() included. eventually, all
calls to bcopy should be changed to calls to memcpy() or memmove()
as appropriate -- hopefully never the latter -- with an option to
use bcopy instead.)
add support for the preprocessor macro LIBSA_NO_DISKLABEL_MSGS, which
causes disklabel() to return '1' as msg rather than a string. Can
be used if the boot blocks don't care about the string, and need to
save the space.
add support for the preprocessor macro LIBSA_SINGLE_FILESYSTEM, which
if defined causes all of the file system switch code to be removed.
Its value should be the name of the file system supported by the
boot block, e.g. "ufs" for the FFS file system. calls to the
file system functions open, close, etc., which were previously
done through a function switch are then done via direct invocation
of <fs>_open, <fs>_close, etc. (e.g. ufs_open, ...).
add support for the preprocessor macro LIBSA_SINGLE_DEVICE, which
does the equivalent of LIBSA_SINGLE_FILESYSTEM but for the device
switch table. Device entry pointes are expected to be named
<dev>foo, e.g. the 'strategy' routine used when LIBSA_SINGLE_DEVICE
is set to 'disk' is diskstrategy.
make ufs.c f_nindir array be unsigned ints. the fact that it was signed
caused ufs.c to require signed division routines (which were otherwise
unnecessary for a small boot block).

That got broken in KNFifying.

Add missing prototypes and KNF the lot.

Change sd.transparent to sd.compressed, so that we default to non-
compressed mode when we zero out the structure. Check_header() now
does not force us to uncompressed mode if we read no data (EOF);
it leaves the default, so that if we check at the end of a file,
we don't set the file to uncompressed mode and blow up later lseeks
on it.

Catch errors from underlying reads, ie where oread() returns -1.
(Original code used fread() which never returns -1, so this case was
not handled.)

Avoid user space headers for standalone programs.
Don't use sys/lib/libkern or sys/lib/libz if not standalone
(ie, user space test programs).

Bring prototypes into scope.

In close(), if the file descriptor was used for writing, don't free
data structures that weren't allocated. Fix sanity-checked
by Matthias Drochner.

code to open/close/read/lseek gzipped files, from Matthias Drochner.