Block and MTD drivers may be opened and managed as though they were character drivers. But this is really sleight of hand; there is a hidden character driver proxy that mediates the interface to the block and MTD drivers in this case.
fstat(), however, did not account for this. It would report the characteristics of the proxy character driver, not of the underlying block or MTD driver.
This change corrects that. fstat now checks if the character driver is such a proxy and, if so, reports the characteristics of the underlying block or MTD driver, not the proxy character driver.
fs/driver and fs/mount: Add mount() support for file systems that require MTD drivers (vs. block drivers).
fs/drivers: Add support for named MTD drivers in the psuedo file system. This will, eventually, allow us to mount file systems that need MTD drivers without having to fake an intervening block driver.
Squashed commit of the following:
fs/cromfs: Now depends on EXPERIMENTAL because it is not yet verified.
fs/cromfs: This commit brings the CROMFS file system to code complete. Still completely untested. Next steps: Need a tool to generate CROMFS file system images and a test case under apps/
fs/cromfs: Add logic to traverse the in-memory file system nodes.
fs/cromfs: Add initial support for an in-memory, compressed, read-only file system.
There are two issues with it however:
1. Reading from file system on a per packet basis could be slow. I think it probably should have a small, in-memory cache of most frequently used routes for good problem.
2. Currently the delroute logic is disabled due to a problem with the design. NuttX does not currently support truncate(). Therefore, it is not possible to delete entries from the routing table file.
In this current implementation, that leaves the last entry intact at the end of the file. An alternative design might include a tag on each record to indicate if the record is valid or not. That would work but would add complexity to the other routing table functions.
The existing implementation is available for testing purposes only if CONFIG_EXPERIMENTAL=y.
Squashed commit of the following:
net/route: The current delroute design depends on file truncation. However, NuttX does not currently support truncate. Alternative, more complex designs are possible but not implemented. At present the file routing table are otherwise functional but the delroute logic is disabled via CONFIG_EXPERIMENTAL. Enable it only if you plan to fix it.
net/route: Fix some issues with locking routing table files.
net/route: Add partial implementation of delroute for the case where the routing table is in a file.
net/route: Add support for seeking to positions in the routing table.
net/route: Add net_addroute_ipv4/6() using a file-based routing table.
net/route: Add net_foreach_ipv4/4() using a file-based routing table.
net/route: Initial build, configuration, and fs utilies to support routing tables in a file.
