23 lines
1.1 KiB
Plaintext
23 lines
1.1 KiB
Plaintext
[Not yet complete]
|
|
Cygwin has recently adopted something called the "cygwin heap". This is
|
|
an internal heap that is inherited by forked/execed children. It
|
|
consists of process specific information that should be inherited. So
|
|
things like the file descriptor table, the current working directory,
|
|
and the chroot value live there.
|
|
|
|
The cygheap is also used to pass argv information to a child process.
|
|
There is a problem here, though. If you allocate space for argv on the
|
|
heap and then exec a process the child process (1) will happily use the
|
|
space in the heap. But what happens when that process execs another
|
|
process (2)? The space used by child process (1) still is being used in
|
|
child process (2) but it is basically just a memory leak.
|
|
|
|
To rectify this problem, memory used by child process 1 is tagged in
|
|
such a way that child process 2 will know to delete it. This is in
|
|
cygheap_fixup_in_child.
|
|
|
|
The cygheap memory allocation functions are adapted from memory
|
|
allocators developed by DJ Delorie. They are similar to early BSD
|
|
malloc and are intended to be relatively lightweight and relatively
|
|
fast.
|