was not fun and I am not entirely certain of the correctness, but it seems
to work. (in fact, side by side testing of this code vs the x86 version
turned up hidden bugs in the x86 code).
testing and real-life applications:
1) If you returned from the thread function, you got a segv instead of
calling _exit() with your return code.
2) clean up some bogus stack management. There was also an underflow
on function return.
3) when making syscalls, the kernel is expecting to have to leave space
for the function's return address. We need to duplicate this. It was
an accident that the rfork syscall actually worked here. :-/
the number of times I have given this to people and got asked: why isn't
it in libc? It is impossible to do this without assembler glue to reset
the stack for the new child process.
int rfork_thread(flags, stack_addr, start_fnc, start_arg)
int flags; Flags to rfork system call. See rfork(2).
void *stack_addr; Top of stack for thread.
int (*start_fnc)(void *); Address of thread function to call in child.
void *start_arg; Argument to pass to the thread function in child.
This is deliberately not documented or prototyped in includes until the
corresponding alpha version is written.
strdup()) rather than pointing it at something that's free()d
(via freeaddrinfo(res)) before the function returns.
I appreciate that this is an API change, but it's the only way
(AFAIK) of doing this without breaking existing code that uses
rcmd{,_af}().
Pointed out by: phkmalloc
management involving rcmd_af(), getaddrinfo(), freeaddrinfo(), etc.
We set *ahost to point to ai->canonname; and later free the ai-> stuff
and still leave the old pointers in *ahost to the freed data.
Perhaps the best way to deal with this is a static buffer or a static
strdup() that is freed on the next iteration or something. This gives
me headaches just thinking about this.
The new 'AJ' default for malloc() tripped this up.
of the processing of the recursion, "scan" would be pointing to O_CH
(or O_QUEST), which would then be interpreted as being the end character
for altoffset().
We avoid this by properly increasing scan before leaving the switch.
Without this, something like (a?b?)?cc would result in a g->moffset of
1 instead of 2.
I added a case to the soon-to-be-imported regex(3) test code to catch
this error.
string may be found (from the beginning of the pattern), the point
at which must is found minus that offset may actually point to some
place before the start of the text.
In that case, make start = start.
Alternatively, this could be tested for in the preceding if, but it
did not occur to me. :-)
Caught by: regex(3) test code