xref: /freebsd/contrib/lua/src/ldump.c (revision a03411e84728e9b267056fd31c7d1d9d1dc1b01e)
1 /*
2 ** $Id: ldump.c $
3 ** save precompiled Lua chunks
4 ** See Copyright Notice in lua.h
5 */
6 
7 #define ldump_c
8 #define LUA_CORE
9 
10 #include "lprefix.h"
11 
12 
13 #include <limits.h>
14 #include <stddef.h>
15 
16 #include "lua.h"
17 
18 #include "lobject.h"
19 #include "lstate.h"
20 #include "lundump.h"
21 
22 
23 typedef struct {
24   lua_State *L;
25   lua_Writer writer;
26   void *data;
27   int strip;
28   int status;
29 } DumpState;
30 
31 
32 /*
33 ** All high-level dumps go through dumpVector; you can change it to
34 ** change the endianness of the result
35 */
36 #define dumpVector(D,v,n)	dumpBlock(D,v,(n)*sizeof((v)[0]))
37 
38 #define dumpLiteral(D, s)	dumpBlock(D,s,sizeof(s) - sizeof(char))
39 
40 
41 static void dumpBlock (DumpState *D, const void *b, size_t size) {
42   if (D->status == 0 && size > 0) {
43     lua_unlock(D->L);
44     D->status = (*D->writer)(D->L, b, size, D->data);
45     lua_lock(D->L);
46   }
47 }
48 
49 
50 #define dumpVar(D,x)		dumpVector(D,&x,1)
51 
52 
53 static void dumpByte (DumpState *D, int y) {
54   lu_byte x = (lu_byte)y;
55   dumpVar(D, x);
56 }
57 
58 
59 /*
60 ** 'dumpSize' buffer size: each byte can store up to 7 bits. (The "+6"
61 ** rounds up the division.)
62 */
63 #define DIBS    ((sizeof(size_t) * CHAR_BIT + 6) / 7)
64 
65 static void dumpSize (DumpState *D, size_t x) {
66   lu_byte buff[DIBS];
67   int n = 0;
68   do {
69     buff[DIBS - (++n)] = x & 0x7f;  /* fill buffer in reverse order */
70     x >>= 7;
71   } while (x != 0);
72   buff[DIBS - 1] |= 0x80;  /* mark last byte */
73   dumpVector(D, buff + DIBS - n, n);
74 }
75 
76 
77 static void dumpInt (DumpState *D, int x) {
78   dumpSize(D, x);
79 }
80 
81 
82 static void dumpNumber (DumpState *D, lua_Number x) {
83   dumpVar(D, x);
84 }
85 
86 
87 static void dumpInteger (DumpState *D, lua_Integer x) {
88   dumpVar(D, x);
89 }
90 
91 
92 static void dumpString (DumpState *D, const TString *s) {
93   if (s == NULL)
94     dumpSize(D, 0);
95   else {
96     size_t size = tsslen(s);
97     const char *str = getstr(s);
98     dumpSize(D, size + 1);
99     dumpVector(D, str, size);
100   }
101 }
102 
103 
104 static void dumpCode (DumpState *D, const Proto *f) {
105   dumpInt(D, f->sizecode);
106   dumpVector(D, f->code, f->sizecode);
107 }
108 
109 
110 static void dumpFunction(DumpState *D, const Proto *f, TString *psource);
111 
112 static void dumpConstants (DumpState *D, const Proto *f) {
113   int i;
114   int n = f->sizek;
115   dumpInt(D, n);
116   for (i = 0; i < n; i++) {
117     const TValue *o = &f->k[i];
118     int tt = ttypetag(o);
119     dumpByte(D, tt);
120     switch (tt) {
121       case LUA_VNUMFLT:
122         dumpNumber(D, fltvalue(o));
123         break;
124       case LUA_VNUMINT:
125         dumpInteger(D, ivalue(o));
126         break;
127       case LUA_VSHRSTR:
128       case LUA_VLNGSTR:
129         dumpString(D, tsvalue(o));
130         break;
131       default:
132         lua_assert(tt == LUA_VNIL || tt == LUA_VFALSE || tt == LUA_VTRUE);
133     }
134   }
135 }
136 
137 
138 static void dumpProtos (DumpState *D, const Proto *f) {
139   int i;
140   int n = f->sizep;
141   dumpInt(D, n);
142   for (i = 0; i < n; i++)
143     dumpFunction(D, f->p[i], f->source);
144 }
145 
146 
147 static void dumpUpvalues (DumpState *D, const Proto *f) {
148   int i, n = f->sizeupvalues;
149   dumpInt(D, n);
150   for (i = 0; i < n; i++) {
151     dumpByte(D, f->upvalues[i].instack);
152     dumpByte(D, f->upvalues[i].idx);
153     dumpByte(D, f->upvalues[i].kind);
154   }
155 }
156 
157 
158 static void dumpDebug (DumpState *D, const Proto *f) {
159   int i, n;
160   n = (D->strip) ? 0 : f->sizelineinfo;
161   dumpInt(D, n);
162   dumpVector(D, f->lineinfo, n);
163   n = (D->strip) ? 0 : f->sizeabslineinfo;
164   dumpInt(D, n);
165   for (i = 0; i < n; i++) {
166     dumpInt(D, f->abslineinfo[i].pc);
167     dumpInt(D, f->abslineinfo[i].line);
168   }
169   n = (D->strip) ? 0 : f->sizelocvars;
170   dumpInt(D, n);
171   for (i = 0; i < n; i++) {
172     dumpString(D, f->locvars[i].varname);
173     dumpInt(D, f->locvars[i].startpc);
174     dumpInt(D, f->locvars[i].endpc);
175   }
176   n = (D->strip) ? 0 : f->sizeupvalues;
177   dumpInt(D, n);
178   for (i = 0; i < n; i++)
179     dumpString(D, f->upvalues[i].name);
180 }
181 
182 
183 static void dumpFunction (DumpState *D, const Proto *f, TString *psource) {
184   if (D->strip || f->source == psource)
185     dumpString(D, NULL);  /* no debug info or same source as its parent */
186   else
187     dumpString(D, f->source);
188   dumpInt(D, f->linedefined);
189   dumpInt(D, f->lastlinedefined);
190   dumpByte(D, f->numparams);
191   dumpByte(D, f->is_vararg);
192   dumpByte(D, f->maxstacksize);
193   dumpCode(D, f);
194   dumpConstants(D, f);
195   dumpUpvalues(D, f);
196   dumpProtos(D, f);
197   dumpDebug(D, f);
198 }
199 
200 
201 static void dumpHeader (DumpState *D) {
202   dumpLiteral(D, LUA_SIGNATURE);
203   dumpByte(D, LUAC_VERSION);
204   dumpByte(D, LUAC_FORMAT);
205   dumpLiteral(D, LUAC_DATA);
206   dumpByte(D, sizeof(Instruction));
207   dumpByte(D, sizeof(lua_Integer));
208   dumpByte(D, sizeof(lua_Number));
209   dumpInteger(D, LUAC_INT);
210   dumpNumber(D, LUAC_NUM);
211 }
212 
213 
214 /*
215 ** dump Lua function as precompiled chunk
216 */
217 int luaU_dump(lua_State *L, const Proto *f, lua_Writer w, void *data,
218               int strip) {
219   DumpState D;
220   D.L = L;
221   D.writer = w;
222   D.data = data;
223   D.strip = strip;
224   D.status = 0;
225   dumpHeader(&D);
226   dumpByte(&D, f->sizeupvalues);
227   dumpFunction(&D, f, NULL);
228   return D.status;
229 }
230 
231