NAME¶
pidl - An IDL compiler written in Perl
SYNOPSIS¶
pidl --help
pidl [--outputdir[=OUTNAME]] [--includedir DIR...] [--parse-idl-tree]
[--dump-idl-tree] [--dump-ndr-tree] [--header[=OUTPUT]] [--python[=OUTPUT]]
[--ndr-parser[=OUTPUT]] [--client] [--server] [--warn-compat] [--quiet]
[--verbose] [--template] [--ws-parser[=OUTPUT]] [--diff] [--dump-idl]
[--tdr-parser[=OUTPUT]] [--samba3-ndr-client[=OUTPUT]]
[--samba3-ndr-server[=OUTPUT]] [--typelib=[OUTPUT]] [<idlfile>.idl]...
DESCRIPTION¶
pidl is an IDL compiler written in Perl that aims to be somewhat compatible with
the midl compiler. IDL is short for "Interface Definition Language".
pidl can generate stubs for DCE/RPC server code, DCE/RPC client code and
Wireshark dissectors for DCE/RPC traffic.
IDL compilers like pidl take a description of an interface as their input and
use it to generate C (though support for other languages may be added later)
code that can use these interfaces, pretty print data sent using these
interfaces, or even generate Wireshark dissectors that can parse data sent
over the wire by these interfaces.
pidl takes IDL files in the same format as is used by midl, converts it to a
.pidl file (which contains pidl's internal representation of the interface)
and can then generate whatever output you need. .pidl files should be used for
debugging purposes only. Write your interface definitions in .idl format.
The goal of pidl is to implement a IDL compiler that can be used while
developing the RPC subsystem in Samba (for both marshalling/unmarshalling and
debugging purposes).
OPTIONS¶
- --help
- Show list of available options.
- --version
- Show pidl version
- --outputdir OUTNAME
- Write output files to the specified directory. Defaults to
the current directory.
- --includedir DIR
- Add DIR to the search path used by the preprocessor. This
option can be specified multiple times.
- --parse-idl-tree
- Read internal tree structure from input files rather than
assuming they contain IDL.
- --dump-idl
- Generate a new IDL file. File will be named
OUTNAME.idl.
- --header
- Generate a C header file for the specified interface.
Filename defaults to OUTNAME.h.
- --ndr-parser
- Generate a C file and C header containing NDR parsers. The
filename for the parser defaults to ndr_OUTNAME.c. The header filename
will be the parser filename with the extension changed from .c to .h.
- --tdr-parser
- Generate a C file and C header containing TDR parsers. The
filename for the parser defaults to tdr_OUTNAME.c. The header filename
will be the parser filename with the extension changed from .c to .h.
- --typelib
- Write type information to the specified file.
- --server
- Generate boilerplate for the RPC server that implements the
interface. Filename defaults to ndr_OUTNAME_s.c.
- --template
- Generate stubs for a RPC server that implements the
interface. Output will be written to stdout.
- --ws-parser
- Generate an Wireshark dissector (in C) and header file. The
dissector filename defaults to packet-dcerpc-OUTNAME.c while the header
filename defaults to packet-dcerpc-OUTNAME.h.
Pidl will read additional data from an Wireshark conformance file if
present. Such a file should have the same location as the IDL file but
with the extension cnf rather than idl. See
Parse::Pidl::Wireshark::Conformance for details on the format of this
file.
- --diff
- Parse an IDL file, generate a new IDL file based on the
internal data structures and see if there are any differences with the
original IDL file. Useful for debugging pidl.
- --dump-idl-tree
- Tell pidl to dump the internal tree representation of an
IDL file the to disk. Useful for debugging pidl.
- --dump-ndr-tree
- Tell pidl to dump the internal NDR information tree it
generated from the IDL file to disk. Useful for debugging pidl.
- --samba3-ndr-client
- Generate client calls for Samba3, to be placed in
rpc_client/. Instead of calling out to the code in Samba3's rpc_parse/,
this will call out to Samba4's NDR code instead.
- --samba3-ndr-server
- Generate server calls for Samba3, to be placed in
rpc_server/. Instead of calling out to the code in Samba3's rpc_parse/,
this will call out to Samba4's NDR code instead.
IDL SYNTAX¶
IDL files are always preprocessed using the C preprocessor.
Pretty much everything in an interface (the interface itself, functions,
parameters) can have attributes (or properties whatever name you give them).
Attributes always prepend the element they apply to and are surrounded by
square brackets ([]). Multiple attributes are separated by comma's; arguments
to attributes are specified between parentheses.
See the section COMPATIBILITY for the list of attributes that pidl supports.
C-style comments can be used.
A conformant array is one with that ends in [*] or []. The strange things about
conformant arrays are that they can only appear as the last element of a
structure (unless there is a pointer to the conformant array, of course) and
the array size appears before the structure itself on the wire.
So, in this example:
typedef struct {
long abc;
long count;
long foo;
[size_is(count)] long s[*];
} Struct1;
it appears like this:
[size_is] [abc] [count] [foo] [s...]
the first [size_is] field is the allocation size of the array, and occurs before
the array elements and even before the structure alignment.
Note that
size_is() can refer to a constant, but that doesn't change the
wire representation. It does not make the array a fixed array.
midl.exe would write the above array as the following C header:
typedef struct {
long abc;
long count;
long foo;
long s[1];
} Struct1;
pidl takes a different approach, and writes it like this:
typedef struct {
long abc;
long count;
long foo;
long *s;
} Struct1;
VARYING ARRAYS¶
A varying array looks like this:
typedef struct {
long abc;
long count;
long foo;
[size_is(count)] long *s;
} Struct1;
This will look like this on the wire:
[abc] [count] [foo] [PTR_s] [count] [s...]
FIXED ARRAYS¶
A fixed array looks like this:
typedef struct {
long s[10];
} Struct1;
The NDR representation looks just like 10 separate long declarations. The array
size is not encoded on the wire.
pidl also supports "inline" arrays, which are not part of the IDL/NDR
standard. These are declared like this:
typedef struct {
uint32 foo;
uint32 count;
uint32 bar;
long s[count];
} Struct1;
This appears like this:
[foo] [count] [bar] [s...]
Fixed arrays are an extension added to support some of the strange embedded
structures in security descriptors and spoolss.
This section is by no means complete. See the OpenGroup and MSDN documentation
for additional information.
COMPATIBILITY WITH MIDL¶
Missing features in pidl¶
The following MIDL features are not (yet) implemented in pidl or are implemented
with an incompatible interface:
- •
- Asynchronous communication
- •
- Typelibs (.tlb files)
- •
- Datagram support (ncadg_*)
Supported attributes and statements¶
in, out, ref, length_is, switch_is, size_is, uuid, case, default, string,
unique, ptr, pointer_default, v1_enum, object, helpstring, range, local,
call_as, endpoint, switch_type, progid, coclass, iid_is, represent_as,
transmit_as, import, include, cpp_quote.
PIDL Specific properties¶
- public
- The [public] property on a structure or union is a pidl
extension that forces the generated pull/push functions to be non-static.
This allows you to declare types that can be used between modules. If you
don't specify [public] then pull/push functions for other than top-level
functions are declared static.
- noprint
- The [noprint] property is a pidl extension that allows you
to specify that pidl should not generate a ndr_print_*() function for that
structure or union. This is used when you wish to define your own print
function that prints a structure in a nicer manner. A good example is the
use of [noprint] on dom_sid, which allows the pretty-printing of
SIDs.
- value
- The [value(expression)] property is a pidl extension that
allows you to specify the value of a field when it is put on the wire.
This allows fields that always have a well-known value to be automatically
filled in, thus making the API more programmer friendly. The expression
can be any C expression.
- relative
- The [relative] property can be supplied on a pointer. When
it is used it declares the pointer as a spoolss style "relative"
pointer, which means it appears on the wire as an offset within the
current encapsulating structure. This is not part of normal IDL/NDR, but
it is a very useful extension as it avoids the manual encoding of many
complex structures.
- subcontext(length)
- Specifies that a size of length bytes should be
read, followed by a blob of that size, which will be parsed as NDR.
subcontext() is deprecated now, and should not be used in new code.
Instead, use represent_as() or transmit_as().
- flag
- Specify boolean options, mostly used for low-level NDR
options. Several options can be specified using the | character. Note that
flags are inherited by substructures!
- nodiscriminant
- The [nodiscriminant] property on a union means that the
usual uint16 discriminent field at the start of the union on the wire is
omitted. This is not normally allowed in IDL/NDR, but is used for some
spoolss structures.
- charset(name)
- Specify that the array or string uses the specified
charset. If this attribute is specified, pidl will take care of converting
the character data from this format to the host format. Commonly used
values are UCS2, DOS and UTF8.
Unsupported MIDL properties or statements¶
aggregatable, appobject, async_uuid, bindable, control, defaultbind,
defaultcollelem, defaultvalue, defaultvtable, dispinterface, displaybind,
dual, entry, first_is, helpcontext, helpfile, helpstringcontext,
helpstringdll, hidden, idl_module, idl_quote, id, immediatebind, importlib,
includelib, last_is, lcid, licensed, max_is, module, ms_union,
no_injected_text, nonbrowsable, noncreatable, nonextensible, odl,
oleautomation, optional, pragma, propget, propputref, propput, readonly,
requestedit, restricted, retval, source, uidefault, usesgetlasterror, vararg,
vi_progid, wire_marshal.
EXAMPLES¶
# Generating an Wireshark parser
$ ./pidl --ws-parser -- atsvc.idl
# Generating a TDR parser and header
$ ./pidl --tdr-parser --header -- regf.idl
# Generating a Samba3 client and server
$ ./pidl --samba3-ndr-client --samba3-ndr-server -- dfs.idl
# Generating a Samba4 NDR parser, client and server
$ ./pidl --ndr-parser --ndr-client --ndr-server -- samr.idl
SEE ALSO¶
http://msdn.microsoft.com/library/en-us/rpc/rpc/field_attributes.asp
<
http://msdn.microsoft.com/library/en-us/rpc/rpc/field_attributes.asp>,
<
http://wiki.wireshark.org/DCE/RPC>, <
http://www.samba.org/>,
yapp(1)
LICENSE¶
pidl is licensed under the GNU General Public License
<
http://www.gnu.org/licenses/gpl.html>.
AUTHOR¶
pidl was written by Andrew Tridgell, Stefan Metzmacher, Tim Potter and Jelmer
Vernooij. The current maintainer is Jelmer Vernooij.
This manpage was written by Jelmer Vernooij, partially based on the original
pidl README by Andrew Tridgell.