1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/*
* Copyright © 2023 Michael Smith <mikesmiffy128@gmail.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
#include "con_.h"
#include "dictmaptree.h"
#include "engineapi.h"
#include "errmsg.h"
#include "feature.h"
#include "gamedata.h"
#include "gametype.h"
#include "intdefs.h"
#include "mem.h"
#include "vcall.h"
#include "x86.h"
#include "x86util.h"
FEATURE()
DECL_VFUNC_DYN(void *, PEntityOfEntIndex, int)
static struct edict **edicts = 0;
struct edict *ent_getedict(int idx) {
if (edicts) {
// globalvars->edicts seems to be null when disconnected
if (!*edicts) return 0;
return mem_offset(*edicts, sz_edict * idx);
}
else {
return PEntityOfEntIndex(engserver, idx);
}
}
void *ent_get(int idx) {
struct edict *e = ent_getedict(idx);
if (!e) return 0;
return e->ent_unknown;
}
struct CEntityFactory {
struct CEntityFactory_vtable {
void /*IServerNetworkable*/ *(*VCALLCONV Create)(
struct CEntityFactory *this, const char *name);
void (*VCALLCONV Destroy)(struct CEntityFactory *this,
void /*IServerNetworkable*/ *networkable);
usize (*VCALLCONV GetEntitySize)(struct CEntityFactory *this);
} *vtable;
};
struct CEntityFactoryDictionary {
void **vtable;
struct CUtlDict_p_ushort dict;
};
#ifdef _WIN32 // TODO(linux): this'll be different too, leaving out for now
static struct CEntityFactoryDictionary *entfactorydict = 0;
static inline bool find_entfactorydict(con_cmdcb dumpentityfactories_cb) {
const uchar *insns = (const uchar *)dumpentityfactories_cb;
for (const uchar *p = insns; p - insns < 64;) {
// EntityFactoryDictionary() is inlined, and returns a static, which is
// lazy-inited (trivia: this was old MSVC, so it's not thread-safe like
// C++ requires nowadays). for some reason the init flag is set using
// OR, and then the instance is put in ECX to call the ctor
if (p[0] == X86_ORMRW && p[6] == X86_MOVECXI && p[11] == X86_CALL) {
entfactorydict = mem_loadptr(p + 7);
return true;
}
NEXT_INSN(p, "entity factory dictionary");
}
return false;
}
#endif
const struct CEntityFactory *ent_getfactory(const char *name) {
#ifdef _WIN32
if (entfactorydict) {
return CUtlDict_p_ushort_findval(&entfactorydict->dict, name);
}
#endif
return 0;
}
typedef void (*VCALLCONV ctor_func)(void *);
static inline ctor_func findctor(const struct CEntityFactory *factory,
const char *classname) {
#ifdef _WIN32
const uchar *insns = (const uchar *)factory->vtable->Create;
// every Create() method follows the same pattern. after calling what is
// presumably operator new(), it copies the return value from EAX into ECX
// and then calls the constructor.
for (const uchar *p = insns; p - insns < 32;) {
if (p[0] == X86_MOVRMW && p[1] == 0xC8 && p[2] == X86_CALL) {
return (ctor_func)(p + 7 + mem_loadoffset(p + 3));
}
// duping NEXT_INSN macro here in the name of a nicer message
int len = x86_len(p);
if (len == -1) {
errmsg_errorx("unknown or invalid instruction looking for %s "
"constructor", classname);
return 0;
}
p += len;
}
#else
#warning TODO(linux): this will be different of course
#endif
return 0;
}
void **ent_findvtable(const struct CEntityFactory *factory,
const char *classname) {
#ifdef _WIN32
ctor_func ctor = findctor(factory, classname);
if (!ctor) return 0;
const uchar *insns = (const uchar *)ctor;
// the constructor itself should do *(void**)this = &vtable; almost right
// away, so look for the first immediate load into indirect register
for (const uchar *p = insns; p - insns < 24;) {
if (p[0] == X86_MOVMIW && (p[1] & 0xF8) == 0) return mem_loadptr(p + 2);
int len = x86_len(p);
if (len == -1) {
errmsg_errorx("unknown or invalid instruction looking for %s "
"vtable pointer", classname);
return 0;
}
p += len;
}
#else
#warning TODO(linux): this will be different of course
#endif
return 0;
}
INIT {
#ifdef _WIN32 // TODO(linux): above
struct con_cmd *dumpentityfactories = con_findcmd("dumpentityfactories");
if (!dumpentityfactories || !find_entfactorydict(dumpentityfactories->cb)) {
errmsg_warnx("server entity factories unavailable");
}
#endif
// for PEntityOfEntIndex we don't really have to do any more init, we
// can just call the function later.
if (has_vtidx_PEntityOfEntIndex) return true;
if (globalvars && has_off_edicts) {
edicts = mem_offset(globalvars, off_edicts);
return true;
}
errmsg_warnx("not implemented for this engine");
return false;
}
// vi: sw=4 ts=4 noet tw=80 cc=80
|
