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://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.