| /* |
| ** $Id: lmem.c,v 1.80 2010/12/20 18:17:46 roberto Exp roberto $ |
| ** Interface to Memory Manager |
| ** See Copyright Notice in lua.h |
| */ |
| |
| |
| #include <stddef.h> |
| |
| #define lmem_c |
| #define LUA_CORE |
| |
| #include "lua.h" |
| |
| #include "ldebug.h" |
| #include "ldo.h" |
| #include "lgc.h" |
| #include "lmem.h" |
| #include "lobject.h" |
| #include "lstate.h" |
| |
| |
| |
| /* |
| ** About the realloc function: |
| ** void * frealloc (void *ud, void *ptr, size_t osize, size_t nsize); |
| ** (`osize' is the old size, `nsize' is the new size) |
| ** |
| ** * frealloc(ud, NULL, x, s) creates a new block of size `s' (no |
| ** matter 'x'). |
| ** |
| ** * frealloc(ud, p, x, 0) frees the block `p' |
| ** (in this specific case, frealloc must return NULL); |
| ** particularly, frealloc(ud, NULL, 0, 0) does nothing |
| ** (which is equivalent to free(NULL) in ANSI C) |
| ** |
| ** frealloc returns NULL if it cannot create or reallocate the area |
| ** (any reallocation to an equal or smaller size cannot fail!) |
| */ |
| |
| |
| |
| #define MINSIZEARRAY 4 |
| |
| |
| void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems, |
| int limit, const char *what) { |
| void *newblock; |
| int newsize; |
| if (*size >= limit/2) { /* cannot double it? */ |
| if (*size >= limit) /* cannot grow even a little? */ |
| luaG_runerror(L, "too many %s (limit is %d)", what, limit); |
| newsize = limit; /* still have at least one free place */ |
| } |
| else { |
| newsize = (*size)*2; |
| if (newsize < MINSIZEARRAY) |
| newsize = MINSIZEARRAY; /* minimum size */ |
| } |
| newblock = luaM_reallocv(L, block, *size, newsize, size_elems); |
| *size = newsize; /* update only when everything else is OK */ |
| return newblock; |
| } |
| |
| |
| void *luaM_toobig (lua_State *L) { |
| luaG_runerror(L, "memory allocation error: block too big"); |
| return NULL; /* to avoid warnings */ |
| } |
| |
| |
| |
| /* |
| ** generic allocation routine. |
| */ |
| void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) { |
| void *newblock; |
| global_State *g = G(L); |
| size_t realosize = (block) ? osize : 0; |
| lua_assert((realosize == 0) == (block == NULL)); |
| #if defined(HARDMEMTESTS) |
| if (nsize > realosize && g->gcrunning) |
| luaC_fullgc(L, 1); /* force a GC whenever possible */ |
| #endif |
| newblock = (*g->frealloc)(g->ud, block, osize, nsize); |
| if (newblock == NULL && nsize > 0) { |
| api_check(L, nsize > realosize, |
| "realloc cannot fail when shrinking a block"); |
| if (g->gcrunning) { |
| luaC_fullgc(L, 1); /* try to free some memory... */ |
| newblock = (*g->frealloc)(g->ud, block, osize, nsize); /* try again */ |
| } |
| if (newblock == NULL) |
| luaD_throw(L, LUA_ERRMEM); |
| } |
| lua_assert((nsize == 0) == (newblock == NULL)); |
| g->GCdebt = (g->GCdebt + nsize) - realosize; |
| #if defined(TRACEMEM) |
| { /* auxiliary patch to monitor garbage collection. |
| ** To plot, gnuplot with following command: |
| ** plot TRACEMEM using 1:2 with lines, TRACEMEM using 1:3 with lines |
| */ |
| static unsigned long total = 0; /* our "time" */ |
| static FILE *f = NULL; /* output file */ |
| total++; /* "time" always grows */ |
| if ((total % 200) == 0) { |
| if (f == NULL) f = fopen(TRACEMEM, "w"); |
| fprintf(f, "%lu %u %d %d\n", total, |
| g->totalbytes, g->GCdebt, g->gcstate * 1000); |
| } |
| } |
| #endif |
| |
| return newblock; |
| } |
| |