compat32, which we deal with properly). It would be possible to get
those working too, but it is not worth the code complexity.
This makes binaries compiled with -mcmodel=medlow (and ancient binaries)
work again on sparc64, smoothing the upgrade path.
ok: christos
Reduce obfuscation of errno handling. There is only one purpose
non-local errno handling is needed for: Inside el_wgets(), several
functions call down indirectly to el_wgetc(), many of them via the
dispatch table. When el_wgetc() fails, it does properly report
failure, but then various cleanup is done which may clobber errno.
But when returning due to failure, el_wgets() wants to have errno
set to the reason of the original read failure, not to the reason
of some subsequent failure of some cleanup operation. So el_wgetc()
needs to save errno, and if it's non-zero, el_wgets() needs to
restore it on failure.
This core logic is currently obscured by the fact that el_errno
is set and inspected at some additional places where it isn't needed.
Besides, since el_wgetc() and and el_wgets() are both in read.c,
el_errno does not need to be in struct editline, it can and should
be local to read.c in struct el_read_t.
Let's look at what can be simplified.
1. keymacro_get() abuses el_errno instead of having a proper
error return code. Adding that error return code is easy
because node_trav() already detects the condition and an
adequate code is already defined. Returning it, testing
for it in read_getcmd(), and returning with error from there
removes the need to inspect el_errno from el_wgets() after
calling read_getcmd().
Note that resetting lastchar and cursor and clearing buffer[0]
is irrelevant. The code returns from el_wgets() right afterwards.
Outside el_wgets(), these variables are no longer relevant.
When el_wgets() is called the next time, it will call ch_reset()
anyway, resetting the two pointers. And as long as lastchar
points to the beginning of the buffer, the contents of the
buffer won't be used for anything.
2. read_getcmd() doesn't need to set el_errno again after el_wgetc()
failure since el_wgetc() already did so. While here, remove
the silly "if EOF or error" comments from the el_wgetc()
return value tests. It's a public interface documented in a
manual, so people working on the implementation can obviously
be expected to know how it works. It's a case of
count++; /* Increment count. */
3. In the two code paths of el_wgets() that lead up to "goto noedit",
there is no need to save the errno because nothing that might
change it happens before returning.
For clarity, since el_wgets() is the function restoring the errno,
also move initializing it to the same function.
Finally, note that restoring errno when the saved value is zero is
wrong. No library code is ever allowed to clear a previously set
value of errno. Only application programs are allowed to do that,
and even they usually don't need to do so, except when using certain
ill-designed interfaces like strtol(3).
I tested that the behaviour remains sane in the following cases,
all during execution of el_wgets(3) and with a signal handler
for USR1 installed without SA_RESTART.
* Enter some text and maybe move around a bit.
Then send a USR1 signal.
The signal gets processed, then read_char() resumes reading.
Send another USR1 signal.
Now el_wgets() sets errno=EINTR and returns -1.
* Press Ctrl-V to activate ed-quoted-insert.
Then send a USR1 signal.
The signal gets processed, then read_char() resumes reading.
Send another USR1 signal.
ed_quoted_insert() returns ed_end_of_file(), i.e. CC_EOF,
and el_wgets() returns 0.
* Press a key starting a keyboard macro.
Then send a USR1 signal.
The signal gets processed, then read_char() resumes reading.
Send another USR1 signal.
Now el_wgets() sets errno=EINTR and returns -1.
* Press : to enter builtin command mode.
Start typing a command.
Then send a USR1 signal.
The signal gets processed, then read_char() resumes reading.
Send another USR1 signal.
Now c_gets() returns -1, ed_command() beeps and returns CC_REFRESH,
and el_wgets() resumes operation as it should.
I also tested with "el_set(el, EL_EDITMODE, 0)", and it returns
the right value and sets errno correctly.
sockets sitting in the accept filter can consume the entire listen queue,
such that the application is never able to handle any connections. Handle
this by simply passing through the oldest queued cxn when the queue is full.
This is fair because the longer a cxn lingers in the queue (stays connected
but does not meet the requirements of the filter for passage) the more likely
it is to be passed through, at which point the application can dispose of it.
Works because none of our accept filters actually allocate private state
per-cxn. If they did, we'd have to fix the API bug that there is presently
no way to tell an accf to finish/deallocate for a single cxn (accf_destroy
kills off the entire filter instance for a given listen socket).
currently belonging to the chared module. The read module does so
from three of its functions, while no other module uses the macro
data, not even the chared module itself. That's quite logical
because macros are a feature of input handling, all of which is
done by the read module, and none by the chared module. So move
the data into the read modules's own opaque data structure, struct
el_read_t.
That simplifies internal interfaces in several respects: The
semi-public chared.h has one fewer struct, one fewer #define, and
one fewer member in struct el_chared_t; all three move to one single
C file, read.c, and are now module-local. And the internal interface
function ch_reset() needs one fewer argument, making the code of many
functions in various modules more readable.
The price is one additional internal interface function, read_end(),
10 lines long including comments, called publicly from exactly one
place: el_end() in el.c. That's hardly an increase in complexity
since most other modules already have their *_end() function, read.c
was the odd one out not having one.
From Ingo Schwarze
makemandb(8), man(1) already use -C as an option to take man.conf path,
so use the same option for whatis(1) and apropos(1) for consitency.
apropos was using -C/-c to disable/enable context of the search
matches, change that to -M/-m respectively.
name, document the return values, expand the list of affected
functions, warn against using EL_GETCFN, and clarify some wording
and notation. (Ingo Schwarze)
Remainder of fix for PR kern/51135: if there is an entropy source
that can produce arbitrarily much data, as in rump, then nothing
should ever block indefinitely waiting for data.
rumpuser_random is limited to 32 bytes at a time -- which would be
reasonable, except that there are too many buffers in the way between
entropy sources and users of the entropy pool.
Partial fix for PR kern/51135.
of the commit log message, but this is easier for releng to find when
they start collecting info for 8.0
If anyone else wants to edit this entry, please feel free.
When allocating memory, the kernel allocates physical pages and virtual
addresses for these pages. In order to optimize allocations smaller
than PAGE_SIZE, uvm_km_kmem_alloc can allocate a single physical page
and take its virtual address in the direct map in high virtual memory.
This direct map is set up at boot time, its PTEs do not change, and
therefore they don't need to be kentered. These high virtual PTEs being
constant, the permissions of the areas they point to are fixed at boot
time and cannot change.
The problem is that at boot time, they are created with RWX permissions.
Therefore, allocations smaller than PAGE_SIZE in the kernel heap are all
executable: mbufs, pnbufs, small kmem allocations, etc.
Fix this by setting the NOX bit in the direct map pages at boot time. We
also set the NOX bit in the temporary tmpva, since it does not need to
be executable either.
This also makes the U-area non executable on amd64.
