| /* |
| ** $Id: lmem.c,v 1.13 1999/02/26 15:50:10 roberto Exp roberto $ |
| ** Interface to Memory Manager |
| ** See Copyright Notice in lua.h |
| */ |
| |
| |
| #include <stdlib.h> |
| |
| #include "lmem.h" |
| #include "lstate.h" |
| #include "lua.h" |
| |
| |
| /* |
| ** real ANSI systems do not need these tests; |
| ** but some systems (Sun OS) are not that ANSI... |
| */ |
| #ifdef OLD_ANSI |
| #define realloc(b,s) ((b) == NULL ? malloc(s) : (realloc)(b, s)) |
| #define free(b) if (b) (free)(b) |
| #endif |
| |
| |
| #define MINSIZE 16 /* minimum size for "growing" vectors */ |
| |
| |
| |
| #ifndef DEBUG |
| |
| |
| static unsigned long power2 (unsigned long n) { |
| unsigned long p = MINSIZE; |
| while (p<=n) p<<=1; |
| return p; |
| } |
| |
| |
| void *luaM_growaux (void *block, unsigned long nelems, int inc, int size, |
| char *errormsg, unsigned long limit) { |
| unsigned long newn = nelems+inc; |
| if ((newn ^ nelems) <= nelems || /* still the same power of 2 limit? */ |
| (nelems > 0 && newn < MINSIZE)) /* or block already is MINSIZE? */ |
| return block; /* do not need to reallocate */ |
| else { /* it crossed a power of 2 boundary; grow to next power */ |
| if (newn >= limit) |
| lua_error(errormsg); |
| newn = power2(newn); |
| if (newn > limit) |
| newn = limit; |
| return luaM_realloc(block, newn*size); |
| } |
| } |
| |
| |
| /* |
| ** generic allocation routine. |
| */ |
| void *luaM_realloc (void *block, unsigned long size) { |
| size_t s = (size_t)size; |
| if (s != size) |
| lua_error("memory allocation error: block too big"); |
| if (size == 0) { |
| free(block); /* block may be NULL, that is OK for free */ |
| return NULL; |
| } |
| block = realloc(block, s); |
| if (block == NULL) |
| lua_error(memEM); |
| return block; |
| } |
| |
| |
| |
| #else |
| /* DEBUG */ |
| |
| #include <string.h> |
| |
| |
| void *luaM_growaux (void *block, unsigned long nelems, int inc, int size, |
| char *errormsg, unsigned long limit) { |
| unsigned long newn = nelems+inc; |
| if (newn >= limit) |
| lua_error(errormsg); |
| return luaM_realloc(block, newn*size); |
| } |
| |
| |
| #define HEADER (sizeof(double)) |
| |
| #define MARK 55 |
| |
| unsigned long numblocks = 0; |
| unsigned long totalmem = 0; |
| |
| |
| static void *checkblock (void *block) { |
| unsigned long *b = (unsigned long *)((char *)block - HEADER); |
| unsigned long size = *b; |
| LUA_ASSERT(*(((char *)b)+size+HEADER) == MARK, |
| "corrupted block"); |
| numblocks--; |
| totalmem -= size; |
| return b; |
| } |
| |
| |
| void *luaM_realloc (void *block, unsigned long size) { |
| unsigned long realsize = HEADER+size+1; |
| if (realsize != (size_t)realsize) |
| lua_error("memory allocation error: block too big"); |
| if (size == 0) { |
| if (block) { |
| unsigned long *b = (unsigned long *)((char *)block - HEADER); |
| memset(block, -1, *b); /* erase block */ |
| block = checkblock(block); |
| } |
| free(block); |
| return NULL; |
| } |
| if (block) |
| block = checkblock(block); |
| block = (unsigned long *)realloc(block, realsize); |
| if (block == NULL) |
| lua_error(memEM); |
| totalmem += size; |
| numblocks++; |
| *(unsigned long *)block = size; |
| *(((char *)block)+size+HEADER) = MARK; |
| return (unsigned long *)((char *)block+HEADER); |
| } |
| |
| |
| #endif |