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-rw-r--r--source/luametatex/source/luacore/lua54/src/lmem.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/source/luametatex/source/luacore/lua54/src/lmem.c b/source/luametatex/source/luacore/lua54/src/lmem.c
new file mode 100644
index 000000000..9029d588c
--- /dev/null
+++ b/source/luametatex/source/luacore/lua54/src/lmem.c
@@ -0,0 +1,201 @@
+/*
+** $Id: lmem.c $
+** Interface to Memory Manager
+** See Copyright Notice in lua.h
+*/
+
+#define lmem_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <stddef.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+#if defined(EMERGENCYGCTESTS)
+/*
+** First allocation will fail whenever not building initial state.
+** (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 (completestate(g) && ns > 0) /* frees never fail */
+ return NULL; /* fail */
+ else /* normal allocation */
+ return (*g->frealloc)(g->ud, block, os, ns);
+}
+#else
+#define firsttry(g,block,os,ns) ((*g->frealloc)(g->ud, block, os, ns))
+#endif
+
+
+
+
+
+/*
+** 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.
+*/
+
+
+
+
+/*
+** {==================================================================
+** 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));
+ (*g->frealloc)(g->ud, 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.
+** The GC should not be called while 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.
+*/
+static void *tryagain (lua_State *L, void *block,
+ size_t osize, size_t nsize) {
+ global_State *g = G(L);
+ if (completestate(g) && !g->gcstopem) {
+ luaC_fullgc(L, 1); /* try to free some memory... */
+ return (*g->frealloc)(g->ud, block, osize, nsize); /* try again */
+ }
+ else return NULL; /* cannot free any memory without a full state */
+}
+
+
+/*
+** 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;
+ }
+}