mirror of
https://git.tartarus.org/simon/putty.git
synced 2025-01-09 17:38:00 +00:00
005ca6b257
This is the companion to the BinarySink system I introduced a couple of weeks ago, and provides the same type-genericity which will let me use the same get_* routines on an SSH packet, an SFTP packet or anything else that chooses to include an implementing substructure. However, unlike BinarySink which contained a (one-function) vtable, BinarySource contains only mutable data fields - so another thing you might very well want to do is to simply instantiate a bare one without any containing object at all. I couldn't quite coerce C into letting me use the same setup macro in both cases, so I've arranged a BinarySource_INIT you can use on larger implementing objects and a BinarySource_BARE_INIT you can use on a BinarySource not contained in anything. The API follows the general principle that even if decoding fails, the decode functions will always return _some_ kind of value, with the same dynamically-allocated-ness they would have used for a completely successful value. But they also set an error flag in the BinarySource which can be tested later. So instead of having to decode a 10-field packet by means of 10 separate 'if (!get_foo(src)) throw error' clauses, you can just write 10 'variable = get_foo(src)' statements followed by a single check of get_err(src), and if the error check fails, you have to do exactly the same set of frees you would have after a successful decode.
79 lines
2.3 KiB
C
79 lines
2.3 KiB
C
/*
|
|
* defs.h: initial definitions for PuTTY.
|
|
*
|
|
* The rule about this header file is that it can't depend on any
|
|
* other header file in this code base. This is where we define
|
|
* things, as much as we can, that other headers will want to refer
|
|
* to, such as opaque structure types and their associated typedefs,
|
|
* or macros that are used by other headers.
|
|
*/
|
|
|
|
#ifndef PUTTY_DEFS_H
|
|
#define PUTTY_DEFS_H
|
|
|
|
#include <stddef.h>
|
|
|
|
#ifndef FALSE
|
|
#define FALSE 0
|
|
#endif
|
|
#ifndef TRUE
|
|
#define TRUE 1
|
|
#endif
|
|
|
|
typedef struct conf_tag Conf;
|
|
typedef struct backend_tag Backend;
|
|
typedef struct terminal_tag Terminal;
|
|
|
|
typedef struct Filename Filename;
|
|
typedef struct FontSpec FontSpec;
|
|
|
|
typedef struct bufchain_tag bufchain;
|
|
|
|
typedef struct strbuf strbuf;
|
|
|
|
struct RSAKey;
|
|
|
|
#include <stdint.h>
|
|
typedef uint32_t uint32;
|
|
|
|
typedef struct BinarySink BinarySink;
|
|
typedef struct BinarySource BinarySource;
|
|
|
|
typedef struct SockAddr_tag *SockAddr;
|
|
|
|
typedef struct Socket_vtable Socket_vtable;
|
|
typedef struct Plug_vtable Plug_vtable;
|
|
|
|
/* Note indirection: for historical reasons (it used to be closer to
|
|
* the OS socket type), the type that most code uses for a socket is
|
|
* 'Socket', not 'Socket *'. So an implementation of Socket or Plug
|
|
* has a 'const Socket *' field for the vtable pointer, and the
|
|
* 'Socket' type returned to client code is a pointer to _that_ in
|
|
* turn. */
|
|
typedef const Socket_vtable **Socket;
|
|
typedef const Plug_vtable **Plug;
|
|
|
|
/*
|
|
* A small structure wrapping up a (pointer, length) pair so that it
|
|
* can be conveniently passed to or from a function.
|
|
*/
|
|
typedef struct ptrlen {
|
|
const void *ptr;
|
|
size_t len;
|
|
} ptrlen;
|
|
|
|
/* Do a compile-time type-check of 'to_check' (without evaluating it),
|
|
* as a side effect of returning the value 'to_return'. Note that
|
|
* although this macro double-*expands* to_return, it always
|
|
* *evaluates* exactly one copy of it, so it's side-effect safe. */
|
|
#define TYPECHECK(to_check, to_return) \
|
|
(sizeof(to_check) ? (to_return) : (to_return))
|
|
|
|
/* Return a pointer to the object of structure type 'type' whose field
|
|
* with name 'field' is pointed at by 'object'. */
|
|
#define FROMFIELD(object, type, field) \
|
|
TYPECHECK(object == &((type *)0)->field, \
|
|
((type *)(((char *)(object)) - offsetof(type, field))))
|
|
|
|
#endif /* PUTTY_DEFS_H */
|