Mypal/xpcom/typelib/xpt/xpt_struct.h

367 lines
12 KiB
C

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* Structures matching the in-memory representation of typelib structures.
* http://www.mozilla.org/scriptable/typelib_file.html
*/
#ifndef __xpt_struct_h__
#define __xpt_struct_h__
#include "xpt_arena.h"
#include <stdint.h>
extern "C" {
/*
* Originally, I was going to have structures that exactly matched the on-disk
* representation, but that proved difficult: different compilers can pack
* their structs differently, and that makes overlaying them atop a
* read-from-disk byte buffer troublesome. So now I just have some structures
* that are used in memory, and we're going to write a nice XDR library to
* write them to disk and stuff. It is pure joy. -- shaver
*/
/* Structures for the typelib components */
typedef struct XPTHeader XPTHeader;
typedef struct XPTInterfaceDirectoryEntry XPTInterfaceDirectoryEntry;
typedef struct XPTInterfaceDescriptor XPTInterfaceDescriptor;
typedef struct XPTConstDescriptor XPTConstDescriptor;
typedef struct XPTMethodDescriptor XPTMethodDescriptor;
typedef struct XPTParamDescriptor XPTParamDescriptor;
typedef struct XPTTypeDescriptor XPTTypeDescriptor;
typedef struct XPTTypeDescriptorPrefix XPTTypeDescriptorPrefix;
#ifndef nsID_h__
/*
* We can't include nsID.h, because it's full of C++ goop and we're not doing
* C++ here, so we define our own minimal struct. We protect against multiple
* definitions of this struct, though, and use the same field naming.
*/
struct nsID {
uint32_t m0;
uint16_t m1;
uint16_t m2;
uint8_t m3[8];
};
typedef struct nsID nsID;
#endif
/*
* Every XPCOM typelib file begins with a header.
*/
struct XPTHeader {
// Some of these fields exists in the on-disk format but don't need to be
// stored in memory (other than very briefly, which can be done with local
// variables).
//uint8_t magic[16];
uint8_t major_version;
uint8_t minor_version;
uint16_t num_interfaces;
//uint32_t file_length;
XPTInterfaceDirectoryEntry *interface_directory;
//uint32_t data_pool;
};
#define XPT_MAGIC "XPCOM\nTypeLib\r\n\032"
/* For error messages. */
#define XPT_MAGIC_STRING "XPCOM\\nTypeLib\\r\\n\\032"
#define XPT_MAJOR_VERSION 0x01
#define XPT_MINOR_VERSION 0x02
/* Any file with a major version number of XPT_MAJOR_INCOMPATIBLE_VERSION
* or higher is to be considered incompatible by this version of xpt and
* we will refuse to read it. We will return a header with magic, major and
* minor versions set from the file. num_interfaces will be set to zero to
* confirm our inability to read the file; i.e. even if some client of this
* library gets out of sync with us regarding the agreed upon value for
* XPT_MAJOR_INCOMPATIBLE_VERSION, anytime num_interfaces is zero we *know*
* that this library refused to read the file due to version incompatibility.
*/
#define XPT_MAJOR_INCOMPATIBLE_VERSION 0x02
/*
* A contiguous array of fixed-size InterfaceDirectoryEntry records begins at
* the byte offset identified by the interface_directory field in the file
* header. The array is used to quickly locate an interface description
* using its IID. No interface should appear more than once in the array.
*/
struct XPTInterfaceDirectoryEntry {
nsID iid;
char *name;
// This field exists in the on-disk format. But it isn't used so we don't
// allocate space for it in memory.
//char *name_space;
XPTInterfaceDescriptor *interface_descriptor;
};
/*
* An InterfaceDescriptor describes a single XPCOM interface, including all of
* its methods.
*/
struct XPTInterfaceDescriptor {
/* This field ordering minimizes the size of this struct.
* The fields are serialized on disk in a different order.
* See DoInterfaceDescriptor().
*/
XPTMethodDescriptor *method_descriptors;
XPTConstDescriptor *const_descriptors;
XPTTypeDescriptor *additional_types;
uint16_t parent_interface;
uint16_t num_methods;
uint16_t num_constants;
uint8_t flags;
/* additional_types are used for arrays where we may need multiple
* XPTTypeDescriptors for a single XPTMethodDescriptor. Since we still
* want to have a simple array of XPTMethodDescriptor (each with a single
* embedded XPTTypeDescriptor), a XPTTypeDescriptor can have a reference
* to an 'additional_type'. That reference is an index in this
* "additional_types" array. So a given XPTMethodDescriptor might have
* a whole chain of these XPTTypeDescriptors to represent, say, a multi
* dimensional array.
*
* Note that in the typelib file these additional types are stored 'inline'
* in the MethodDescriptor. But, in the typelib MethodDescriptors can be
* of varying sizes, where in XPT's in memory mapping of the data we want
* them to be of fixed size. This additional_types scheme is here to allow
* for that.
*/
uint8_t num_additional_types;
};
#define XPT_ID_SCRIPTABLE 0x80
#define XPT_ID_FUNCTION 0x40
#define XPT_ID_BUILTINCLASS 0x20
#define XPT_ID_MAIN_PROCESS_SCRIPTABLE_ONLY 0x10
#define XPT_ID_FLAGMASK 0xf0
#define XPT_ID_IS_SCRIPTABLE(flags) (!!(flags & XPT_ID_SCRIPTABLE))
#define XPT_ID_IS_FUNCTION(flags) (!!(flags & XPT_ID_FUNCTION))
#define XPT_ID_IS_BUILTINCLASS(flags) (!!(flags & XPT_ID_BUILTINCLASS))
#define XPT_ID_IS_MAIN_PROCESS_SCRIPTABLE_ONLY(flags) (!!(flags & XPT_ID_MAIN_PROCESS_SCRIPTABLE_ONLY))
/*
* A TypeDescriptor is a variable-size record used to identify the type of a
* method argument or return value.
*
* There are three types of TypeDescriptors:
*
* SimpleTypeDescriptor
* InterfaceTypeDescriptor
* InterfaceIsTypeDescriptor
*
* The tag field in the prefix indicates which of the variant TypeDescriptor
* records is being used, and hence the way any remaining fields should be
* parsed. Values from 0 to 17 refer to SimpleTypeDescriptors. The value 18
* designates an InterfaceTypeDescriptor, while 19 represents an
* InterfaceIsTypeDescriptor.
*/
/* why bother with a struct? - other code relies on this being a struct */
struct XPTTypeDescriptorPrefix {
uint8_t flags;
};
/* flag bits */
#define XPT_TDP_FLAGMASK 0xe0
#define XPT_TDP_TAGMASK (~XPT_TDP_FLAGMASK)
#define XPT_TDP_TAG(tdp) ((tdp).flags & XPT_TDP_TAGMASK)
/*
* The following enum maps mnemonic names to the different numeric values
* of XPTTypeDescriptor->tag.
*/
enum XPTTypeDescriptorTags {
TD_INT8 = 0,
TD_INT16 = 1,
TD_INT32 = 2,
TD_INT64 = 3,
TD_UINT8 = 4,
TD_UINT16 = 5,
TD_UINT32 = 6,
TD_UINT64 = 7,
TD_FLOAT = 8,
TD_DOUBLE = 9,
TD_BOOL = 10,
TD_CHAR = 11,
TD_WCHAR = 12,
TD_VOID = 13,
TD_PNSIID = 14,
TD_DOMSTRING = 15,
TD_PSTRING = 16,
TD_PWSTRING = 17,
TD_INTERFACE_TYPE = 18,
TD_INTERFACE_IS_TYPE = 19,
TD_ARRAY = 20,
TD_PSTRING_SIZE_IS = 21,
TD_PWSTRING_SIZE_IS = 22,
TD_UTF8STRING = 23,
TD_CSTRING = 24,
TD_ASTRING = 25,
TD_JSVAL = 26
};
struct XPTTypeDescriptor {
XPTTypeDescriptorPrefix prefix;
// The memory layout here doesn't exactly match (for the appropriate types)
// the on-disk format. This is to save memory.
union {
// Used for TD_INTERFACE_IS_TYPE.
struct {
uint8_t argnum;
} interface_is;
// Used for TD_PSTRING_SIZE_IS, TD_PWSTRING_SIZE_IS.
struct {
uint8_t argnum;
//uint8_t argnum2; // Present on disk, omitted here.
} pstring_is;
// Used for TD_ARRAY.
struct {
uint8_t argnum;
//uint8_t argnum2; // Present on disk, omitted here.
uint8_t additional_type; // uint16_t on disk, uint8_t here;
// in practice it never exceeds 20.
} array;
// Used for TD_INTERFACE_TYPE.
struct {
// We store the 16-bit iface value as two 8-bit values in order to
// avoid 16-bit alignment requirements for XPTTypeDescriptor, which
// reduces its size and also the size of XPTParamDescriptor.
uint8_t iface_hi8;
uint8_t iface_lo8;
} iface;
} u;
};
/*
* A ConstDescriptor is a variable-size record that records the name and
* value of a scoped interface constant.
*
* The types of the method parameter are restricted to the following subset
* of TypeDescriptors:
*
* int8_t, uint8_t, int16_t, uint16_t, int32_t, uint32_t,
* int64_t, uint64_t, wchar_t, char
*
* The type (and thus the size) of the value record is determined by the
* contents of the associated TypeDescriptor record. For instance, if type
* corresponds to int16_t, then value is a two-byte record consisting of a
* 16-bit signed integer.
*/
union XPTConstValue {
int8_t i8;
uint8_t ui8;
int16_t i16;
uint16_t ui16;
int32_t i32;
uint32_t ui32;
int64_t i64;
uint64_t ui64;
char ch;
uint16_t wch;
}; /* varies according to type */
struct XPTConstDescriptor {
char *name;
XPTTypeDescriptor type;
union XPTConstValue value;
};
/*
* A ParamDescriptor is a variable-size record used to describe either a
* single argument to a method or a method's result.
*/
struct XPTParamDescriptor {
uint8_t flags;
XPTTypeDescriptor type;
};
/* flag bits */
#define XPT_PD_IN 0x80
#define XPT_PD_OUT 0x40
#define XPT_PD_RETVAL 0x20
#define XPT_PD_SHARED 0x10
#define XPT_PD_DIPPER 0x08
#define XPT_PD_OPTIONAL 0x04
#define XPT_PD_FLAGMASK 0xfc
#define XPT_PD_IS_IN(flags) (flags & XPT_PD_IN)
#define XPT_PD_IS_OUT(flags) (flags & XPT_PD_OUT)
#define XPT_PD_IS_RETVAL(flags) (flags & XPT_PD_RETVAL)
#define XPT_PD_IS_SHARED(flags) (flags & XPT_PD_SHARED)
#define XPT_PD_IS_DIPPER(flags) (flags & XPT_PD_DIPPER)
#define XPT_PD_IS_OPTIONAL(flags) (flags & XPT_PD_OPTIONAL)
/*
* A MethodDescriptor is a variable-size record used to describe a single
* interface method.
*/
struct XPTMethodDescriptor {
char *name;
XPTParamDescriptor *params;
XPTParamDescriptor result;
uint8_t flags;
uint8_t num_args;
};
/* flag bits */
#define XPT_MD_GETTER 0x80
#define XPT_MD_SETTER 0x40
#define XPT_MD_NOTXPCOM 0x20
#define XPT_MD_HIDDEN 0x08
#define XPT_MD_OPT_ARGC 0x04
#define XPT_MD_CONTEXT 0x02
#define XPT_MD_FLAGMASK 0xfe
#define XPT_MD_IS_GETTER(flags) (flags & XPT_MD_GETTER)
#define XPT_MD_IS_SETTER(flags) (flags & XPT_MD_SETTER)
#define XPT_MD_IS_NOTXPCOM(flags) (flags & XPT_MD_NOTXPCOM)
#define XPT_MD_IS_HIDDEN(flags) (flags & XPT_MD_HIDDEN)
#define XPT_MD_WANTS_OPT_ARGC(flags) (flags & XPT_MD_OPT_ARGC)
#define XPT_MD_WANTS_CONTEXT(flags) (flags & XPT_MD_CONTEXT)
/*
* Annotation records are variable-size records used to store secondary
* information about the typelib, e.g. such as the name of the tool that
* generated the typelib file, the date it was generated, etc. The
* information is stored with very loose format requirements so as to
* allow virtually any private data to be stored in the typelib.
*
* There are two types of Annotations:
*
* EmptyAnnotation
* PrivateAnnotation
*
* The tag field of the prefix discriminates among the variant record
* types for Annotation's. If the tag is 0, this record is an
* EmptyAnnotation. EmptyAnnotation's are ignored - they're only used to
* indicate an array of Annotation's that's completely empty. If the tag
* is 1, the record is a PrivateAnnotation.
*
* We don't actually store annotations; we just skip over them if they are
* present.
*/
#define XPT_ANN_LAST 0x80
#define XPT_ANN_IS_LAST(flags) (flags & XPT_ANN_LAST)
#define XPT_ANN_PRIVATE 0x40
#define XPT_ANN_IS_PRIVATE(flags) (flags & XPT_ANN_PRIVATE)
}
#endif /* __xpt_struct_h__ */