diff options
author | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2017-12-06 16:36:31 -0200 |
---|---|---|
committer | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2017-12-06 16:36:31 -0200 |
commit | 49dfaf7447ab707d17fc6061fe1d59c187e4e221 (patch) | |
tree | a2864af4cacbcd225ca33e27087a6cf39fe6a1de /lmem.h | |
parent | 348fa1ca56efeb81ef66d8f09c3cd1405b0a121d (diff) | |
download | lua-49dfaf7447ab707d17fc6061fe1d59c187e4e221.tar.gz lua-49dfaf7447ab707d17fc6061fe1d59c187e4e221.tar.bz2 lua-49dfaf7447ab707d17fc6061fe1d59c187e4e221.zip |
avoid using one function for different tasks (malloc, free, etc.)
Diffstat (limited to 'lmem.h')
-rw-r--r-- | lmem.h | 53 |
1 files changed, 33 insertions, 20 deletions
@@ -1,5 +1,5 @@ | |||
1 | /* | 1 | /* |
2 | ** $Id: lmem.h,v 1.42 2014/12/19 13:45:40 roberto Exp roberto $ | 2 | ** $Id: lmem.h,v 1.43 2014/12/19 17:26:14 roberto Exp roberto $ |
3 | ** Interface to Memory Manager | 3 | ** Interface to Memory Manager |
4 | ** See Copyright Notice in lua.h | 4 | ** See Copyright Notice in lua.h |
5 | */ | 5 | */ |
@@ -15,11 +15,9 @@ | |||
15 | 15 | ||
16 | 16 | ||
17 | /* | 17 | /* |
18 | ** This macro reallocs a vector 'b' from 'on' to 'n' elements, where | 18 | ** This macro tests whether it is safe to multiply 'n' by the size of |
19 | ** each element has size 'e'. In case of arithmetic overflow of the | 19 | ** type 't' without overflows. Because 'e' is always constant, it avoids |
20 | ** product 'n'*'e', it raises an error (calling 'luaM_toobig'). Because | 20 | ** the runtime division MAX_SIZET/(e). |
21 | ** 'e' is always constant, it avoids the runtime division MAX_SIZET/(e). | ||
22 | ** | ||
23 | ** (The macro is somewhat complex to avoid warnings: The 'sizeof' | 21 | ** (The macro is somewhat complex to avoid warnings: The 'sizeof' |
24 | ** comparison avoids a runtime comparison when overflow cannot occur. | 22 | ** comparison avoids a runtime comparison when overflow cannot occur. |
25 | ** The compiler should be able to optimize the real test by itself, but | 23 | ** The compiler should be able to optimize the real test by itself, but |
@@ -27,10 +25,20 @@ | |||
27 | ** false due to limited range of data type"; the +1 tricks the compiler, | 25 | ** false due to limited range of data type"; the +1 tricks the compiler, |
28 | ** avoiding this warning but also this optimization.) | 26 | ** avoiding this warning but also this optimization.) |
29 | */ | 27 | */ |
28 | #define luaM_testsize(n,e) \ | ||
29 | (sizeof(n) >= sizeof(size_t) && cast(size_t, (n)) + 1 > MAX_SIZET/(e)) | ||
30 | |||
31 | #define luaM_checksize(L,n,e) \ | ||
32 | (luaM_testsize(n,e) ? luaM_toobig(L) : cast_void(0)) | ||
33 | |||
34 | /* | ||
35 | ** This macro reallocs a vector 'b' from 'on' to 'n' elements, where | ||
36 | ** each element has size 'e'. In case of arithmetic overflow of the | ||
37 | ** product 'n'*'e', it raises an error (calling 'luaM_toobig'). | ||
38 | */ | ||
30 | #define luaM_reallocv(L,b,on,n,e) \ | 39 | #define luaM_reallocv(L,b,on,n,e) \ |
31 | (((sizeof(n) >= sizeof(size_t) && cast(size_t, (n)) + 1 > MAX_SIZET/(e)) \ | 40 | (luaM_checksize(L,n,e), \ |
32 | ? luaM_toobig(L) : cast_void(0)) , \ | 41 | luaM_realloc_(L, (b), cast(size_t, on)*(e), cast(size_t, n)*(e))) |
33 | luaM_realloc_(L, (b), (on)*(e), (n)*(e))) | ||
34 | 42 | ||
35 | /* | 43 | /* |
36 | ** Arrays of chars do not need any test | 44 | ** Arrays of chars do not need any test |
@@ -38,32 +46,37 @@ | |||
38 | #define luaM_reallocvchar(L,b,on,n) \ | 46 | #define luaM_reallocvchar(L,b,on,n) \ |
39 | cast(char *, luaM_realloc_(L, (b), (on)*sizeof(char), (n)*sizeof(char))) | 47 | cast(char *, luaM_realloc_(L, (b), (on)*sizeof(char), (n)*sizeof(char))) |
40 | 48 | ||
41 | #define luaM_freemem(L, b, s) luaM_realloc_(L, (b), (s), 0) | 49 | #define luaM_freemem(L, b, s) luaM_free_(L, (b), (s)) |
42 | #define luaM_free(L, b) luaM_realloc_(L, (b), sizeof(*(b)), 0) | 50 | #define luaM_free(L, b) luaM_free_(L, (b), sizeof(*(b))) |
43 | #define luaM_freearray(L, b, n) luaM_realloc_(L, (b), (n)*sizeof(*(b)), 0) | 51 | #define luaM_freearray(L, b, n) luaM_free_(L, (b), (n)*sizeof(*(b))) |
44 | 52 | ||
45 | #define luaM_malloc(L,s) luaM_realloc_(L, NULL, 0, (s)) | 53 | #define luaM_new(L,t) cast(t *, luaM_malloc(L, sizeof(t), 0)) |
46 | #define luaM_new(L,t) cast(t *, luaM_malloc(L, sizeof(t))) | ||
47 | #define luaM_newvector(L,n,t) \ | 54 | #define luaM_newvector(L,n,t) \ |
48 | cast(t *, luaM_reallocv(L, NULL, 0, n, sizeof(t))) | 55 | (luaM_checksize(L,n,sizeof(t)), cast(t *, luaM_malloc(L, (n)*sizeof(t), 0))) |
49 | 56 | ||
50 | #define luaM_newobject(L,tag,s) luaM_realloc_(L, NULL, tag, (s)) | 57 | #define luaM_newobject(L,tag,s) luaM_malloc(L, (s), tag) |
51 | 58 | ||
52 | #define luaM_growvector(L,v,nelems,size,t,limit,e) \ | 59 | #define luaM_growvector(L,v,nelems,size,t,limit,e) \ |
53 | if ((nelems)+1 > (size)) \ | 60 | ((v)=cast(t *, luaM_growaux_(L,v,nelems,&(size),sizeof(t),limit,e))) |
54 | ((v)=cast(t *, luaM_growaux_(L,v,&(size),sizeof(t),limit,e))) | ||
55 | 61 | ||
56 | #define luaM_reallocvector(L, v,oldn,n,t) \ | 62 | #define luaM_reallocvector(L, v,oldn,n,t) \ |
57 | ((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t)))) | 63 | ((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t)))) |
58 | 64 | ||
65 | #define luaM_shrinkvector(L,v,size,fs,t) \ | ||
66 | ((v)=cast(t *, luaM_shrinkvector_(L, v, &(size), fs, sizeof(t)))) | ||
67 | |||
59 | LUAI_FUNC l_noret luaM_toobig (lua_State *L); | 68 | LUAI_FUNC l_noret luaM_toobig (lua_State *L); |
60 | 69 | ||
61 | /* not to be called directly */ | 70 | /* not to be called directly */ |
62 | LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize, | 71 | LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize, |
63 | size_t size); | 72 | size_t size); |
64 | LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int *size, | 73 | LUAI_FUNC void luaM_free_ (lua_State *L, void *block, size_t osize); |
65 | size_t size_elem, int limit, | 74 | LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int nelems, |
75 | int *size, int size_elem, int limit, | ||
66 | const char *what); | 76 | const char *what); |
77 | LUAI_FUNC void *luaM_shrinkvector_ (lua_State *L, void *block, int *nelem, | ||
78 | int final_n, int size_elem); | ||
79 | LUAI_FUNC void *luaM_malloc (lua_State *L, size_t size, int tag); | ||
67 | 80 | ||
68 | #endif | 81 | #endif |
69 | 82 | ||