The previous commit's message claims the race can lead to duplicated
output, use after free, then double-free. That's correct only up to
the use after free. There is no double-free.
Heap corruption (double-free?) has been observed in Changeling,
though. Player logged in (still in sanctuary), map #, crashed within
removecc()'s free(io->data). Partial backtrace:
raise () from /lib64/libc.so.6
abort () from /lib64/libc.so.6
__libc_message () from /lib64/libc.so.6
malloc_printerr () from /lib64/libc.so.6
removecc (ioq=0x251fd10, cc=468) at ../src/lib/gen/ioqueue.c:350
ioq_dequeue (ioq=0x251fd10, cc=468) at ../src/lib/gen/ioqueue.c:135
io_output (iop=0x251fc90, wait=1) at ../src/lib/empthread/io.c:231
recvclient (cmd=0x258d8e0 "", size=1024) at ../src/lib/player/recvclient.c:82
getcommand (combufp=0x2557068 "map #1") at ../src/lib/player/empdis.c:84
I haven't been able to reproduce.
To hopefully catch ioqueue going south earlier, make ioq_dequeue()
oops when it can't dequeue as many bytes as requested.
other. Ensure headers in include/ can be included in any order
(except for econfig-spec.h, which is special). New header types.h to
help avoid inclusion cycles. Sort include directives. Remove some
superflous includes.
platform is evil, and line editing is none of the server's business
anyway. If your client can't deal with the delete key, well, here's a
nickel, kid, get yourself a better computer.
string input other than through parse() or getele() failed to strip
'\r', which could end up in ship names and such.
(getele): Code dealing with '\r' is now redundant, remove. It ceased
to work in rev. 1.6 because input filtering replaces '\r' by '?'.
effect. Replace calls by struct assignment where possible. Replace
clear buffer, copy string to buffer by strncpy(). Use assignment to
clear when that's clearer. Replace overlapping copy through bounce
buffer by memmove(). Replace rest by standard memset() and memcpy().
Also use sizeof() instead of literal array sizes for robustness, and
instead of symbolic array sizes for clarity.