/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│ │ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │ ╚──────────────────────────────────────────────────────────────────────────────╝ │ │ │ Lua │ │ Copyright © 2004-2023 Lua.org, PUC-Rio. │ │ │ │ Permission is hereby granted, free of charge, to any person obtaining │ │ a copy of this software and associated documentation files (the │ │ "Software"), to deal in the Software without restriction, including │ │ without limitation the rights to use, copy, modify, merge, publish, │ │ distribute, sublicense, and/or sell copies of the Software, and to │ │ permit persons to whom the Software is furnished to do so, subject to │ │ the following conditions: │ │ │ │ The above copyright notice and this permission notice shall be │ │ included in all copies or substantial portions of the Software. │ │ │ │ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │ │ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │ │ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │ │ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY │ │ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, │ │ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE │ │ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │ │ │ ╚─────────────────────────────────────────────────────────────────────────────*/ #define lmem_c #define LUA_CORE #include "libc/log/log.h" #include "third_party/lua/ldebug.h" #include "third_party/lua/ldo.h" #include "third_party/lua/lgc.h" #include "third_party/lua/lmem.h" #include "third_party/lua/lobject.h" #include "third_party/lua/lprefix.h" #include "third_party/lua/lstate.h" #include "third_party/lua/lua.h" __static_yoink("lua_notice"); /* ** 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, p, x, 0) frees the block 'p' and returns NULL. ** Particularly, frealloc(ud, NULL, 0, 0) does nothing, ** which is equivalent to free(NULL) in ISO C. ** ** - frealloc(ud, NULL, x, s) creates a new block of size 's' ** (no matter 'x'). Returns NULL if it cannot create the new block. ** ** - otherwise, frealloc(ud, b, x, y) reallocates the block 'b' from ** size 'x' to size 'y'. Returns NULL if it cannot reallocate the ** block to the new size. */ /* ** Macro to call the allocation function. */ #define callfrealloc(g,block,os,ns) ((*g->frealloc)(g->ud, block, os, ns)) /* ** When an allocation fails, it will try again after an emergency ** collection, except when it cannot run a collection. The GC should ** not be called while the state is not fully built, as the collector ** is not yet fully initialized. Also, it should not be called when ** 'gcstopem' is true, because then the interpreter is in the middle of ** a collection step. */ #define cantryagain(g) (completestate(g) && !g->gcstopem) #if defined(EMERGENCYGCTESTS) /* ** First allocation will fail except when freeing a block (frees never ** fail) and when it cannot try again; this fail will trigger 'tryagain' ** and a full GC cycle at every allocation. */ static void *firsttry (global_State *g, void *block, size_t os, size_t ns) { if (ns > 0 && cantryagain(g)) return NULL; /* fail */ else /* normal allocation */ return callfrealloc(g, block, os, ns); } #else #define firsttry(g,block,os,ns) callfrealloc(g, block, os, ns) #endif /* ** {================================================================== ** Functions to allocate/deallocate arrays for the Parser ** =================================================================== */ /* ** Minimum size for arrays during parsing, to avoid overhead of ** reallocating to size 1, then 2, and then 4. All these arrays ** will be reallocated to exact sizes or erased when parsing ends. */ #define MINSIZEARRAY 4 void *luaM_growaux_ (lua_State *L, void *block, int nelems, int *psize, int size_elems, int limit, const char *what) { void *newblock; int size = *psize; if (nelems + 1 <= size) /* does one extra element still fit? */ return block; /* nothing to be done */ if (size >= limit / 2) { /* cannot double it? */ if (l_unlikely(size >= limit)) /* cannot grow even a little? */ luaG_runerror(L, "too many %s (limit is %d)", what, limit); size = limit; /* still have at least one free place */ } else { size *= 2; if (size < MINSIZEARRAY) size = MINSIZEARRAY; /* minimum size */ } lua_assert(nelems + 1 <= size && size <= limit); /* 'limit' ensures that multiplication will not overflow */ newblock = luaM_saferealloc_(L, block, cast_sizet(*psize) * size_elems, cast_sizet(size) * size_elems); *psize = size; /* update only when everything else is OK */ return newblock; } /* ** In prototypes, the size of the array is also its number of ** elements (to save memory). So, if it cannot shrink an array ** to its number of elements, the only option is to raise an ** error. */ void *luaM_shrinkvector_ (lua_State *L, void *block, int *size, int final_n, int size_elem) { void *newblock; size_t oldsize = cast_sizet((*size) * size_elem); size_t newsize = cast_sizet(final_n * size_elem); lua_assert(newsize <= oldsize); newblock = luaM_saferealloc_(L, block, oldsize, newsize); *size = final_n; return newblock; } /* }================================================================== */ l_noret luaM_toobig (lua_State *L) { luaG_runerror(L, "memory allocation error: block too big"); } /* ** Free memory */ void luaM_free_ (lua_State *L, void *block, size_t osize) { global_State *g = G(L); lua_assert((osize == 0) == (block == NULL)); callfrealloc(g, block, osize, 0); g->GCdebt -= osize; } /* ** In case of allocation fail, this function will do an emergency ** collection to free some memory and then try the allocation again. */ static void *tryagain (lua_State *L, void *block, size_t osize, size_t nsize) { global_State *g = G(L); if (cantryagain(g)) { WARNF("reacting to malloc() failure by running lua garbage collector..."); // [jart] luaC_fullgc(L, 1); /* try to free some memory... */ return callfrealloc(g, block, osize, nsize); /* try again */ } else return NULL; /* cannot run an emergency collection */ } /* ** Generic allocation routine. */ void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) { void *newblock; global_State *g = G(L); lua_assert((osize == 0) == (block == NULL)); newblock = firsttry(g, block, osize, nsize); if (l_unlikely(newblock == NULL && nsize > 0)) { newblock = tryagain(L, block, osize, nsize); if (newblock == NULL) /* still no memory? */ return NULL; /* do not update 'GCdebt' */ } lua_assert((nsize == 0) == (newblock == NULL)); g->GCdebt = (g->GCdebt + nsize) - osize; return newblock; } void *luaM_saferealloc_ (lua_State *L, void *block, size_t osize, size_t nsize) { void *newblock = luaM_realloc_(L, block, osize, nsize); if (l_unlikely(newblock == NULL && nsize > 0)) /* allocation failed? */ luaM_error(L); return newblock; } void *luaM_malloc_ (lua_State *L, size_t size, int tag) { if (size == 0) return NULL; /* that's all */ else { global_State *g = G(L); void *newblock = firsttry(g, NULL, tag, size); if (l_unlikely(newblock == NULL)) { newblock = tryagain(L, NULL, tag, size); if (newblock == NULL) luaM_error(L); } g->GCdebt += size; return newblock; } }