Async I/O OS specifities should now handled in OS specific code. Linux
has been done, but other emulation should be handled. See case LINUX_F_SETFL
in sys/compat/linux/common/linux_file.c:linux_sys_fcntl() for more details.
The data that has been collected yet:
Net Free Open Linux SunOS AIX OSF1 Darwin
send SIGIO to write end of pipe Y N N N N N Y Y
send SIGIO to read end of pipe Y Y N N N ? Y ?
send SIGIO to write end of socket Y Y Y N N Y Y Y
send SIGIO to read end of socket Y Y Y Y Y ? Y ?
between creation of a file descriptor and close(2) when using kernel
assisted threads. What we do is stick descriptors in the table, but
mark them as "larval". This causes essentially everything to treat
it as a non-existent descriptor, except for fdalloc(), which sees a
filled slot so that it won't (incorrectly) allocate it again. When
a descriptor is fully constructed, the code that has constructed it
marks it as "mature" (which actually clears the "larval" flag), and
things continue to work as normal.
While here, gather all the code that gets a descriptor from the table
into a fd_getfile() function, and call it, rather than having the
same (sometimes incorrect) code copied all over the place.
only signal handler array sharable between threads
move other random signal stuff from struct proc to struct sigctx
This addresses kern/10981 by Matthew Orgass.
* __HAVE_SYSCALL_INTERN. If this is defined, e_syscall is replaced by
e_syscall_intern, which is called at key places in the kernel. This can be
used to set a MD syscall handler pointer. This obsoletes and replaces the
*_HAS_SEPARATED_SYSCALL flags.
* __HAVE_MINIMAL_EMUL. If this is defined, certain (deprecated) elements in
struct emul are omitted.
*_emul_path variables
change macros CHECK_ALT_{CREAT|EXIST} to use that, 'root' doesn't need
to be passed explicitly any more and *_CHECK_ALT_{CREAT|EXIST} are removed
change explicit emul_find() calls in probe functions to get the emulation
path from the checked exec switch entry's emulation
remove no longer needed header files
add e_flags and e_syscall to struct emul; these are unsed and empty for now
* move all exec-type specific information from struct emul to execsw[] and
provide single struct emul per emulation
* elf:
- kern/exec_elf32.c:probe_funcs[] is gone, execsw[] how has one entry
per emulation and contains pointer to respective probe function
- interp is allocated via MALLOC() rather than on stack
- elf_args structure is allocated via MALLOC() rather than malloc()
* ecoff: the per-emulation hooks moved from alpha and mips specific code
to OSF1 and Ultrix compat code as appropriate, execsw[] has one entry per
emulation supporting ecoff with appropriate probe function
* the makecmds/probe functions don't set emulation, pointer to emulation is
part of appropriate execsw[] entry
* constify couple of structures
FreeBSD-SA00:42.
Change stackgap_alloc to bounds-check the allocation vs. the stack
gap, returning NULL if there isn't room for the allocation.
Change emul_find() to check for a NULL return from stackgap_alloc()
and convert that into ENAMETOOLONG.
Reorder various emulation syscalls so that all *_CHECK_ALT_{EXIST,CREAT}
calls (which turn into emul_find() under the covers come *after* small,
fixed-size stackgap_alloc() calls.
Clean up ibcs2 {get,set}groups.
* Remove the casts to vaddr_t from the round_page() and trunc_page() macros to
make them type-generic, which is necessary i.e. to operate on file offsets
without truncating them.
* In due course, cast pointer arguments to these macros to an appropriate
integral type (paddr_t, vaddr_t).
Originally done by Chuck Silvers, updated by myself.
christos