So far, cftw would search through all directories and files recursively,
until all objects are processed. However, it is interesting for the user
callback to be able to stop this process under specific circumstances.
Now, cftw will pass a pointer to a bool, initialised to false by
default, that can be optionally assigned to true by the user
callback.
Future commits will make use of this feature. For example, this will be
used to limit the number of search results when a user enters a search
term that is too generic and would otherwise generate a large amount of
search results.
This provides a few benefits:
- This will allow searching for directories by name.
- Future commits will allow to remove files and directories, so this
change was also required for cftw.
According to POSIX.1-2017, applications are advised to assign errno(3)
to 0 before a call to readdir(3), and compare errno(3) after the call to
check for errors.
Otherwise, this would generate strings such as "directory//resource" if
dirpath contained a trailing slash, which could be problematic for users
relying on ctfw.
POSIX functions ftw(3) and nftw(3) do not allow passing an opaque
pointer to the callback they call, so it forces the use of statically
allocated data.
ctfw (from "custom ftw") is a custom implementation that solves this,
while also removing unneeded stuff.
This function will be used by future commits.