runtime_loader.h revision 43542cab
1/*
2 * Copyright 2008-2009, Ingo Weinhold, ingo_weinhold@gmx.de.
3 * Copyright 2003-2011, Axel D��rfler, axeld@pinc-software.de.
4 * Distributed under the terms of the MIT License.
5 *
6 * Copyright 2002, Manuel J. Petit. All rights reserved.
7 * Copyright 2001, Travis Geiselbrecht. All rights reserved.
8 * Distributed under the terms of the NewOS License.
9 */
10
11#ifndef _RUNTIME_LOADER_H
12#define _RUNTIME_LOADER_H
13
14
15#include <image.h>
16#include <OS.h>
17
18#include <elf_private.h>
19
20
21// #pragma mark - runtime loader libroot interface
22
23
24struct user_space_program_args;
25struct SymbolLookupInfo;
26
27struct rld_export {
28	// runtime loader API export
29	image_id (*load_add_on)(char const *path, uint32 flags);
30	status_t (*unload_add_on)(image_id imageID);
31	image_id (*load_library)(char const *path, uint32 flags, void **_handle);
32	status_t (*unload_library)(void* handle);
33	status_t (*get_image_symbol)(image_id imageID, char const *symbolName,
34		int32 symbolType, bool recursive, image_id *_inImage, void **_location);
35	status_t (*get_library_symbol)(void* handle, void* caller,
36		const char* symbolName, void **_location);
37	status_t (*get_nth_image_symbol)(image_id imageID, int32 num,
38		char *symbolName, int32 *nameLength, int32 *symbolType,
39		void **_location);
40	status_t (*get_nearest_symbol_at_address)(void* address,
41		image_id* _imageID,	char** _imagePath, char** _imageName,
42		char** _symbolName, int32* _type, void** _location, bool* _exactMatch);
43	status_t (*test_executable)(const char *path, char *interpreter);
44	status_t (*get_executable_architecture)(const char *path,
45		const char** _architecture);
46	status_t (*get_next_image_dependency)(image_id id, uint32 *cookie,
47		const char **_name);
48	void* (*get_tls_address)(unsigned dso, addr_t offset);
49	void (*destroy_thread_tls)();
50
51	status_t (*reinit_after_fork)();
52
53	void (*call_atexit_hooks_for_range)(addr_t start, addr_t size);
54
55	void (*call_termination_hooks)();
56
57	const struct user_space_program_args *program_args;
58	const void* commpage_address;
59	int abi_version;
60};
61
62extern struct rld_export *__gRuntimeLoader;
63
64
65// #pragma mark - runtime loader debugger interface
66
67
68struct RuntimeLoaderSymbolPatcher;
69
70typedef struct elf_region_t {
71	area_id		id;
72	addr_t		start;
73	addr_t		size;
74	addr_t		vmstart;
75	addr_t		vmsize;
76	addr_t		fdstart;
77	addr_t		fdsize;
78	long		delta;
79	uint32		flags;
80} elf_region_t;
81
82typedef struct elf_version_info {
83	uint32		hash;			// version name hash
84	const char	*name;			// version name
85	const char	*file_name;		// dependency file name (needed versions only)
86} elf_version_info;
87
88typedef struct image_t {
89	// image identification
90	char				path[B_PATH_NAME_LENGTH];
91	char				name[B_FILE_NAME_LENGTH];
92	image_id			id;
93	image_type			type;
94
95	struct image_t		*next;
96	struct image_t		*prev;
97	int32				ref_count;
98	uint32				flags;
99
100	uint32				api_version;
101	uint32				abi;
102
103	addr_t 				entry_point;
104	addr_t				init_routine;
105	addr_t				term_routine;
106	addr_t 				dynamic_ptr; 	// pointer to the dynamic section
107
108	// pointer to symbol participation data structures
109	uint32				*symhash;
110	elf_sym				*syms;
111	char				*strtab;
112	elf_rel				*rel;
113	int					rel_len;
114	elf_rela			*rela;
115	int					rela_len;
116	elf_rel				*pltrel;
117	int					pltrel_len;
118	addr_t				*init_array;
119	int					init_array_len;
120	addr_t				*preinit_array;
121	int					preinit_array_len;
122	addr_t				*term_array;
123	int					term_array_len;
124
125	unsigned			dso_tls_id;
126
127	uint32				num_needed;
128	struct image_t		**needed;
129
130	// versioning related structures
131	uint32				num_version_definitions;
132	elf_verdef			*version_definitions;
133	uint32				num_needed_versions;
134	elf_verneed			*needed_versions;
135	elf_versym			*symbol_versions;
136	elf_version_info	*versions;
137	uint32				num_versions;
138
139#ifdef __cplusplus
140	elf_sym*			(*find_undefined_symbol)(struct image_t* rootImage,
141							struct image_t* image,
142							const SymbolLookupInfo& lookupInfo,
143							struct image_t** foundInImage);
144#else
145	elf_sym*			(*find_undefined_symbol)(struct image_t* rootImage,
146							struct image_t* image,
147							const struct SymbolLookupInfo* lookupInfo,
148							struct image_t** foundInImage);
149#endif
150
151	// Singly-linked list of symbol patchers for symbols defined respectively
152	// referenced by this image.
153	struct RuntimeLoaderSymbolPatcher	*defined_symbol_patchers;
154	struct RuntimeLoaderSymbolPatcher	*undefined_symbol_patchers;
155
156	// describes the text and data regions
157	uint32				num_regions;
158	elf_region_t		regions[1];
159} image_t;
160
161typedef struct image_queue_t {
162	image_t *head;
163	image_t *tail;
164} image_queue_t;
165
166// image_t::flags
167#define	IMAGE_FLAG_RTLD_MASK			0x03
168			// RTLD_{LAZY,NOW} | RTLD_{LOCAL,GLOBAL}
169
170#define STRING(image, offset) ((char*)(&(image)->strtab[(offset)]))
171#define SYMNAME(image, sym) STRING(image, (sym)->st_name)
172#define SYMBOL(image, num) (&(image)->syms[num])
173#define HASHTABSIZE(image) ((image)->symhash[0])
174#define HASHBUCKETS(image) ((unsigned int*)&(image)->symhash[2])
175#define HASHCHAINS(image) ((unsigned int*)&(image)->symhash[2+HASHTABSIZE(image)])
176
177
178// The name of the area the runtime loader creates for debugging purposes.
179#define RUNTIME_LOADER_DEBUG_AREA_NAME	"_rld_debug_"
180
181// The contents of the runtime loader debug area.
182typedef struct runtime_loader_debug_area {
183	image_queue_t	*loaded_images;
184} runtime_loader_debug_area;
185
186
187// #pragma mark - runtime loader add-on interface
188
189
190// symbol patcher callback
191typedef void runtime_loader_symbol_patcher(void* cookie,
192	struct image_t* rootImage, struct image_t* image, const char* name,
193	struct image_t** foundInImage, void** symbol, int32* type);
194
195// interface provided to add-ons
196struct runtime_loader_add_on_export {
197	status_t	(*register_defined_symbol_patcher)(struct image_t* image,
198					runtime_loader_symbol_patcher* patcher, void* cookie);
199	void		(*unregister_defined_symbol_patcher)(struct image_t* image,
200					runtime_loader_symbol_patcher* patcher, void* cookie);
201	status_t	(*register_undefined_symbol_patcher)(struct image_t* image,
202					runtime_loader_symbol_patcher* patcher, void* cookie);
203	void		(*unregister_undefined_symbol_patcher)(struct image_t* image,
204					runtime_loader_symbol_patcher* patcher, void* cookie);
205};
206
207
208#define RUNTIME_LOADER_ADD_ON_VERSION	1
209
210typedef struct runtime_loader_add_on {
211	uint32	version;
212	uint32	flags;
213
214	// called after the add-on image has been loaded
215	void	(*init)(struct rld_export* standardInterface,
216				struct runtime_loader_add_on_export* addOnInterface);
217
218	// called whenever the respective image event occurs
219	void	(*image_loaded)(struct image_t* image);
220	void	(*image_relocated)(struct image_t* image);
221	void	(*image_initialized)(struct image_t* image);
222	void	(*image_uninitializing)(struct image_t* image);
223	void	(*image_unloading)(struct image_t* image);
224} runtime_loader_add_on;
225
226// This is the variable a preloaded shared object has to export to get picked up
227// by the runtime loader as an add-on.
228extern runtime_loader_add_on __gRuntimeLoaderAddOn;
229
230#endif	// _RUNTIME_LOADER_H
231