putty-source/be_ssh.c

/*
 * Linking module for programs that are restricted to only using SSH
 * (pscp and psftp). These do not support selection of backend, but
 * must still have a backends[] array mentioning SSH because
 * settings.c will want to consult it during session load.
 */

#include <stdio.h>
#include "putty.h"

const int be_default_protocol = PROT_SSH;

const struct Backend_vtable *const backends[] = {
    &ssh_backend,
    NULL
};
Fix bug in which the SSH-only tools (pscp, psftp) did not honour a nonstandard port number when loading a saved session. Occurs because those tools include be_none.c which defines no entries in backends[] at all, as a result of which settings.c doesn't recognise the word 'ssh' in the saved session's protocol field and instead sets the protocol to something idiotic - which _then_ means that when pscp.c forces the protocol to PROT_SSH, it also resets the port number as it would when overriding a saved session specifying a protocol other than SSH. The immediate solution is to define a new be_ssh.c citing only ssh_backend, and include that in the SSH-only tools. However, I wonder if a better approach (perhaps when I redesign session loading and saving) would be not to be so clever, and just have all the tools contain a complete list of known protocol names for purposes of understanding what's in the saved session data, and complain if you try to use one they don't know how to actually speak. [originally from svn r9254] 2011-07-27 18:43:16 +00:00			`/*`
			`* Linking module for programs that are restricted to only using SSH`
			`* (pscp and psftp). These do not support selection of backend, but`
			`* must still have a backends[] array mentioning SSH because`
			`* settings.c will want to consult it during session load.`
			`*/`

			`#include <stdio.h>`
			`#include "putty.h"`

			`const int be_default_protocol = PROT_SSH;`

Turn Backend into a sensible classoid. Nearly every part of the code that ever handles a full backend structure has historically done it using a pair of pointer variables, one pointing at a constant struct full of function pointers, and the other pointing to a 'void *' state object that's passed to each of those. While I'm modernising the rest of the code, this seems like a good time to turn that into the same more or less type-safe and less cumbersome system as I'm using for other parts of the code, such as Socket, Plug, BinaryPacketProtocol and so forth: the Backend structure contains a vtable pointer, and a system of macro wrappers handles dispatching through that vtable. 2018-09-11 15:23:38 +00:00			`const struct Backend_vtable *const backends[] = {`
Fix bug in which the SSH-only tools (pscp, psftp) did not honour a nonstandard port number when loading a saved session. Occurs because those tools include be_none.c which defines no entries in backends[] at all, as a result of which settings.c doesn't recognise the word 'ssh' in the saved session's protocol field and instead sets the protocol to something idiotic - which _then_ means that when pscp.c forces the protocol to PROT_SSH, it also resets the port number as it would when overriding a saved session specifying a protocol other than SSH. The immediate solution is to define a new be_ssh.c citing only ssh_backend, and include that in the SSH-only tools. However, I wonder if a better approach (perhaps when I redesign session loading and saving) would be not to be so clever, and just have all the tools contain a complete list of known protocol names for purposes of understanding what's in the saved session data, and complain if you try to use one they don't know how to actually speak. [originally from svn r9254] 2011-07-27 18:43:16 +00:00			`&ssh_backend,`
			`NULL`
			`};`