{
MSize osz = sbufsz(sb), len = sbuflen(sb), nsz = osz;
char *b;
+ GCSize flag;
if (nsz < LJ_MIN_SBUF) nsz = LJ_MIN_SBUF;
while (nsz < sz) nsz += nsz;
- b = (char *)lj_mem_realloc(sbufL(sb), sb->b, osz, nsz);
+ flag = sbufflag(sb);
+ if ((flag & SBUF_FLAG_COW)) { /* Copy-on-write semantics. */
+ lj_assertG_(G(sbufL(sb)), sb->w == sb->e, "bad SBuf COW");
+ b = (char *)lj_mem_new(sbufL(sb), nsz);
+ setsbufflag(sb, flag & ~(GCSize)SBUF_FLAG_COW);
+ setgcrefnull(sbufX(sb)->cowref);
+ memcpy(b, sb->b, osz);
+ } else {
+ b = (char *)lj_mem_realloc(sbufL(sb), sb->b, osz, nsz);
+ }
+ if ((flag & SBUF_FLAG_EXT)) {
+ sbufX(sb)->r = sbufX(sb)->r - sb->b + b; /* Adjust read pointer, too. */
+ }
+ /* Adjust buffer pointers. */
sb->b = b;
sb->w = b + len;
sb->e = b + nsz;
+ if ((flag & SBUF_FLAG_BORROW)) { /* Adjust borrowed buffer pointers. */
+ SBuf *bsb = mref(sbufX(sb)->bsb, SBuf);
+ bsb->b = b;
+ bsb->w = b + len;
+ bsb->e = b + nsz;
+ }
}
LJ_NOINLINE char *LJ_FASTCALL lj_buf_need2(SBuf *sb, MSize sz)
LJ_NOINLINE char *LJ_FASTCALL lj_buf_more2(SBuf *sb, MSize sz)
{
- MSize len = sbuflen(sb);
- lj_assertG_(G(sbufL(sb)), sz > sbufleft(sb), "SBuf overflow");
- if (LJ_UNLIKELY(sz > LJ_MAX_BUF || len + sz > LJ_MAX_BUF))
- lj_err_mem(sbufL(sb));
- buf_grow(sb, len + sz);
+ if (sbufisext(sb)) {
+ SBufExt *sbx = (SBufExt *)sb;
+ MSize len = sbufxlen(sbx);
+ if (LJ_UNLIKELY(sz > LJ_MAX_BUF || len + sz > LJ_MAX_BUF))
+ lj_err_mem(sbufL(sbx));
+ if (len + sz > sbufsz(sbx)) { /* Must grow. */
+ buf_grow((SBuf *)sbx, len + sz);
+ } else if (sbufxslack(sbx) < (sbufsz(sbx) >> 3)) {
+ /* Also grow to avoid excessive compactions, if slack < size/8. */
+ buf_grow((SBuf *)sbx, sbuflen(sbx) + sz); /* Not sbufxlen! */
+ return sbx->w;
+ }
+ if (sbx->r != sbx->b) { /* Compact by moving down. */
+ memmove(sbx->b, sbx->r, len);
+ sbx->r = sbx->b;
+ sbx->w = sbx->b + len;
+ lj_assertG_(G(sbufL(sbx)), len + sz <= sbufsz(sbx), "bad SBuf compact");
+ }
+ } else {
+ MSize len = sbuflen(sb);
+ lj_assertG_(G(sbufL(sb)), sz > sbufleft(sb), "SBuf overflow");
+ if (LJ_UNLIKELY(sz > LJ_MAX_BUF || len + sz > LJ_MAX_BUF))
+ lj_err_mem(sbufL(sb));
+ buf_grow(sb, len + sz);
+ }
return sb->w;
}
sb->w = b + n;
sb->e = b + (osz >> 1);
}
+ lj_assertG_(G(sbufL(sb)), !sbufisext(sb), "YAGNI shrink SBufExt");
}
char * LJ_FASTCALL lj_buf_tmp(lua_State *L, MSize sz)
#include "lj_gc.h"
#include "lj_str.h"
-/* Resizable string buffers. SBuf struct definition in lj_obj.h. */
-#define sbufsz(sb) ((MSize)((sb)->e - (sb)->b))
-#define sbuflen(sb) ((MSize)((sb)->w - (sb)->b))
-#define sbufleft(sb) ((MSize)((sb)->e - (sb)->w))
+/* Resizable string buffers. */
-#define sbufL(sb) (mref((sb)->L, lua_State))
-#define setsbufL(sb, l) (setmref((sb)->L, (l)))
+/* The SBuf struct definition is in lj_obj.h:
+** char *w; Write pointer.
+** char *e; End pointer.
+** char *b; Base pointer.
+** MRef L; lua_State, used for buffer resizing. Extension bits in 3 LSB.
+*/
+
+/* Extended string buffer. */
+typedef struct SBufExt {
+ SBufHeader;
+ union {
+ GCRef cowref; /* Copy-on-write object reference. */
+ MRef bsb; /* Borrowed string buffer. */
+ };
+ char *r; /* Read pointer. */
+ int depth; /* Remaining recursion depth. */
+} SBufExt;
+
+#define sbufsz(sb) ((MSize)((sb)->e - (sb)->b))
+#define sbuflen(sb) ((MSize)((sb)->w - (sb)->b))
+#define sbufleft(sb) ((MSize)((sb)->e - (sb)->w))
+#define sbufxlen(sbx) ((MSize)((sbx)->w - (sbx)->r))
+#define sbufxslack(sbx) ((MSize)((sbx)->r - (sbx)->b))
+
+#define SBUF_MASK_FLAG (7)
+#define SBUF_MASK_L (~(GCSize)SBUF_MASK_FLAG)
+#define SBUF_FLAG_EXT 1 /* Extended string buffer. */
+#define SBUF_FLAG_COW 2 /* Copy-on-write buffer. */
+#define SBUF_FLAG_BORROW 4 /* Borrowed string buffer. */
+
+#define sbufL(sb) \
+ ((lua_State *)(void *)(uintptr_t)(mrefu((sb)->L) & SBUF_MASK_L))
+#define setsbufL(sb, l) (setmref((sb)->L, (l)))
+#define setsbufXL(sb, l, flag) \
+ (setmrefu((sb)->L, (GCSize)(uintptr_t)(void *)(l) + (flag)))
+#define setsbufXL_(sb, l) \
+ (setmrefu((sb)->L, (GCSize)(uintptr_t)(void *)(l) | (mrefu((sb)->L) & SBUF_MASK_FLAG)))
+
+#define sbufflag(sb) (mrefu((sb)->L))
+#define sbufisext(sb) (sbufflag((sb)) & SBUF_FLAG_EXT)
+#define sbufiscow(sb) (sbufflag((sb)) & SBUF_FLAG_COW)
+#define sbufisborrow(sb) (sbufflag((sb)) & SBUF_FLAG_BORROW)
+#define sbufX(sb) \
+ (lj_assertG_(G(sbufL(sb)), sbufisext(sb), "not an SBufExt"), (SBufExt *)(sb))
+#define setsbufflag(sb, flag) (setmrefu((sb)->L, (flag)))
/* Buffer management */
LJ_FUNC char *LJ_FASTCALL lj_buf_need2(SBuf *sb, MSize sz);
static LJ_AINLINE void lj_buf_free(global_State *g, SBuf *sb)
{
+ lj_assertG(!sbufisext(sb), "bad free of SBufExt");
lj_mem_free(g, sb->b, sbufsz(sb));
}
return sb->w;
}
+/* Extended buffer management */
+static LJ_AINLINE void lj_bufx_init(lua_State *L, SBufExt *sbx)
+{
+ memset(sbx, 0, sizeof(SBufExt));
+ setsbufXL(sbx, L, SBUF_FLAG_EXT);
+}
+
+static LJ_AINLINE void lj_bufx_init_borrow(lua_State *L, SBufExt *sbx, SBuf *sb)
+{
+ memset(sbx, 0, sizeof(SBufExt));
+ setsbufXL(sbx, L, SBUF_FLAG_EXT | SBUF_FLAG_BORROW);
+ setmref(sbx->bsb, sb);
+ sbx->r = sbx->w = sbx->b = sb->b;
+ sbx->e = sb->e;
+}
+
+static LJ_AINLINE void lj_bufx_init_cow(lua_State *L, SBufExt *sbx,
+ const char *p, MSize len)
+{
+ memset(sbx, 0, sizeof(SBufExt));
+ setsbufXL(sbx, L, SBUF_FLAG_EXT | SBUF_FLAG_COW);
+ sbx->r = sbx->b = (char *)p;
+ sbx->w = sbx->e = (char *)p + len;
+}
+
+static LJ_AINLINE void lj_bufx_reset(SBufExt *sbx)
+{
+ if (sbufiscow(sbx)) {
+ setmrefu(sbx->L, (mrefu(sbx->L) & ~(GCSize)SBUF_FLAG_COW));
+ setgcrefnull(sbx->cowref);
+ sbx->b = sbx->e = NULL;
+ }
+ sbx->r = sbx->w = sbx->b;
+}
+
+static LJ_AINLINE void lj_bufx_free(global_State *g, SBufExt *sbx)
+{
+ if (!sbufiscow(sbx)) lj_mem_free(g, sbx->b, sbufsz(sbx));
+}
+
/* Low-level buffer put operations */
LJ_FUNC SBuf *lj_buf_putmem(SBuf *sb, const void *q, MSize len);
LJ_FUNC SBuf * LJ_FASTCALL lj_buf_putchar(SBuf *sb, int c);
return lj_str_new(L, sb->b, sbuflen(sb));
}
-/* Interim user-accessible string buffer. */
-typedef struct StrBuf {
- SBuf *sb; /* Pointer to system buffer. */
- char *r; /* String buffer read pointer. */
- int depth; /* Remaining recursion depth. */
-} StrBuf;
-
#endif
/* -- Helper functions ---------------------------------------------------- */
-static LJ_AINLINE char *serialize_more(char *w, StrBuf *sbuf, MSize sz)
+static LJ_AINLINE char *serialize_more(char *w, SBufExt *sbx, MSize sz)
{
- if (LJ_UNLIKELY(sz > (MSize)(sbuf->sb->e - w))) {
- sbuf->sb->w = w;
- w = lj_buf_more2(sbuf->sb, sz);
+ if (LJ_UNLIKELY(sz > (MSize)(sbx->e - w))) {
+ sbx->w = w;
+ w = lj_buf_more2((SBuf *)sbx, sz);
}
return w;
}
}
}
-static LJ_NOINLINE char *serialize_ru124_(char *r, char *e, uint32_t *pv)
+static LJ_NOINLINE char *serialize_ru124_(char *r, char *w, uint32_t *pv)
{
uint32_t v = *pv;
if (v != 0xff) {
- if (r >= e) return NULL;
+ if (r >= w) return NULL;
v = ((v & 0x1f) << 8) + *(uint8_t *)r + 0xe0; r++;
} else {
- if (r + 4 > e) return NULL;
+ if (r + 4 > w) return NULL;
v = lj_getu32(r); r += 4;
#if LJ_BE
v = lj_bswap(v);
return r;
}
-static LJ_AINLINE char *serialize_ru124(char *r, char *e, uint32_t *pv)
+static LJ_AINLINE char *serialize_ru124(char *r, char *w, uint32_t *pv)
{
- if (LJ_LIKELY(r < e)) {
+ if (LJ_LIKELY(r < w)) {
uint32_t v = *(uint8_t *)r; r++;
*pv = v;
if (LJ_UNLIKELY(v >= 0xe0)) {
- r = serialize_ru124_(r, e, pv);
+ r = serialize_ru124_(r, w, pv);
}
return r;
}
/* -- Internal serializer ------------------------------------------------- */
/* Put serialized object into buffer. */
-static char *serialize_put(char *w, StrBuf *sbuf, cTValue *o)
+static char *serialize_put(char *w, SBufExt *sbx, cTValue *o)
{
if (LJ_LIKELY(tvisstr(o))) {
const GCstr *str = strV(o);
MSize len = str->len;
- w = serialize_more(w, sbuf, 5+len);
+ w = serialize_more(w, sbx, 5+len);
w = serialize_wu124(w, SER_TAG_STR + len);
w = lj_buf_wmem(w, strdata(str), len);
} else if (tvisint(o)) {
uint32_t x = LJ_BE ? lj_bswap((uint32_t)intV(o)) : (uint32_t)intV(o);
- w = serialize_more(w, sbuf, 1+4);
+ w = serialize_more(w, sbx, 1+4);
*w++ = SER_TAG_INT; memcpy(w, &x, 4); w += 4;
} else if (tvisnum(o)) {
uint64_t x = LJ_BE ? lj_bswap64(o->u64) : o->u64;
- w = serialize_more(w, sbuf, 1+sizeof(lua_Number));
+ w = serialize_more(w, sbx, 1+sizeof(lua_Number));
*w++ = SER_TAG_NUM; memcpy(w, &x, 8); w += 8;
} else if (tvispri(o)) {
- w = serialize_more(w, sbuf, 1);
+ w = serialize_more(w, sbx, 1);
*w++ = (char)(SER_TAG_NIL + ~itype(o));
} else if (tvistab(o)) {
const GCtab *t = tabV(o);
uint32_t narray = 0, nhash = 0, one = 2;
- if (sbuf->depth <= 0) lj_err_caller(sbufL(sbuf->sb), LJ_ERR_BUFFER_DEPTH);
- sbuf->depth--;
+ if (sbx->depth <= 0) lj_err_caller(sbufL(sbx), LJ_ERR_BUFFER_DEPTH);
+ sbx->depth--;
if (t->asize > 0) { /* Determine max. length of array part. */
ptrdiff_t i;
TValue *array = tvref(t->array);
nhash += !tvisnil(&node[i].val);
}
/* Write number of array slots and hash slots. */
- w = serialize_more(w, sbuf, 1+2*5);
+ w = serialize_more(w, sbx, 1+2*5);
*w++ = (char)(SER_TAG_TAB + (nhash ? 1 : 0) + (narray ? one : 0));
if (narray) w = serialize_wu124(w, narray);
if (nhash) w = serialize_wu124(w, nhash);
if (narray) { /* Write array entries. */
cTValue *oa = tvref(t->array) + (one >> 2);
cTValue *oe = tvref(t->array) + narray;
- while (oa < oe) w = serialize_put(w, sbuf, oa++);
+ while (oa < oe) w = serialize_put(w, sbx, oa++);
}
if (nhash) { /* Write hash entries. */
const Node *node = noderef(t->node) + t->hmask;
for (;; node--)
if (!tvisnil(&node->val)) {
- w = serialize_put(w, sbuf, &node->key);
- w = serialize_put(w, sbuf, &node->val);
+ w = serialize_put(w, sbx, &node->key);
+ w = serialize_put(w, sbx, &node->val);
if (--nhash == 0) break;
}
}
- sbuf->depth++;
+ sbx->depth++;
#if LJ_HASFFI
} else if (tviscdata(o)) {
- CTState *cts = ctype_cts(sbufL(sbuf->sb));
+ CTState *cts = ctype_cts(sbufL(sbx));
CType *s = ctype_raw(cts, cdataV(o)->ctypeid);
uint8_t *sp = cdataptr(cdataV(o));
if (ctype_isinteger(s->info) && s->size == 8) {
- w = serialize_more(w, sbuf, 1+8);
+ w = serialize_more(w, sbx, 1+8);
*w++ = (s->info & CTF_UNSIGNED) ? SER_TAG_UINT64 : SER_TAG_INT64;
#if LJ_BE
{ uint64_t u = lj_bswap64(*(uint64_t *)sp); memcpy(w, &u, 8); }
#endif
w += 8;
} else if (ctype_iscomplex(s->info) && s->size == 16) {
- w = serialize_more(w, sbuf, 1+16);
+ w = serialize_more(w, sbx, 1+16);
*w++ = SER_TAG_COMPLEX;
#if LJ_BE
{ /* Only swap the doubles. The re/im order stays the same. */
}
#endif
} else if (tvislightud(o)) {
- uintptr_t ud = (uintptr_t)lightudV(G(sbufL(sbuf->sb)), o);
- w = serialize_more(w, sbuf, 1+sizeof(ud));
+ uintptr_t ud = (uintptr_t)lightudV(G(sbufL(sbx)), o);
+ w = serialize_more(w, sbx, 1+sizeof(ud));
if (ud == 0) {
*w++ = SER_TAG_NULL;
} else if (LJ_32 || checku32(ud)) {
#if LJ_HASFFI
badenc:
#endif
- lj_err_callerv(sbufL(sbuf->sb), LJ_ERR_BUFFER_BADENC, lj_typename(o));
+ lj_err_callerv(sbufL(sbx), LJ_ERR_BUFFER_BADENC, lj_typename(o));
}
return w;
}
/* Get serialized object from buffer. */
-static char *serialize_get(char *r, StrBuf *sbuf, TValue *o)
+static char *serialize_get(char *r, SBufExt *sbx, TValue *o)
{
- char *e = sbuf->sb->e;
+ char *w = sbx->w;
uint32_t tp;
- r = serialize_ru124(r, e, &tp); if (LJ_UNLIKELY(!r)) goto eob;
+ r = serialize_ru124(r, w, &tp); if (LJ_UNLIKELY(!r)) goto eob;
if (LJ_LIKELY(tp >= SER_TAG_STR)) {
uint32_t len = tp - SER_TAG_STR;
- if (LJ_UNLIKELY(len > (uint32_t)(e - r))) goto eob;
- setstrV(sbufL(sbuf->sb), o, lj_str_new(sbufL(sbuf->sb), r, len));
+ if (LJ_UNLIKELY(len > (uint32_t)(w - r))) goto eob;
+ setstrV(sbufL(sbx), o, lj_str_new(sbufL(sbx), r, len));
r += len;
} else if (tp == SER_TAG_INT) {
- if (LJ_UNLIKELY(r + 4 > e)) goto eob;
+ if (LJ_UNLIKELY(r + 4 > w)) goto eob;
setintV(o, (int32_t)(LJ_BE ? lj_bswap(lj_getu32(r)) : lj_getu32(r)));
r += 4;
} else if (tp == SER_TAG_NUM) {
- if (LJ_UNLIKELY(r + 8 > e)) goto eob;
+ if (LJ_UNLIKELY(r + 8 > w)) goto eob;
memcpy(o, r, 8); r += 8;
#if LJ_BE
o->u64 = lj_bswap64(o->u64);
uint32_t narray = 0, nhash = 0;
GCtab *t;
if (tp >= SER_TAG_TAB+2) {
- r = serialize_ru124(r, e, &narray); if (LJ_UNLIKELY(!r)) goto eob;
+ r = serialize_ru124(r, w, &narray); if (LJ_UNLIKELY(!r)) goto eob;
}
if ((tp & 1)) {
- r = serialize_ru124(r, e, &nhash); if (LJ_UNLIKELY(!r)) goto eob;
+ r = serialize_ru124(r, w, &nhash); if (LJ_UNLIKELY(!r)) goto eob;
}
- t = lj_tab_new(sbufL(sbuf->sb), narray, hsize2hbits(nhash));
- settabV(sbufL(sbuf->sb), o, t);
+ t = lj_tab_new(sbufL(sbx), narray, hsize2hbits(nhash));
+ settabV(sbufL(sbx), o, t);
if (narray) {
TValue *oa = tvref(t->array) + (tp >= SER_TAG_TAB+4);
TValue *oe = tvref(t->array) + narray;
- while (oa < oe) r = serialize_get(r, sbuf, oa++);
+ while (oa < oe) r = serialize_get(r, sbx, oa++);
}
if (nhash) {
do {
TValue k, *v;
- r = serialize_get(r, sbuf, &k);
- v = lj_tab_set(sbufL(sbuf->sb), t, &k);
+ r = serialize_get(r, sbx, &k);
+ v = lj_tab_set(sbufL(sbx), t, &k);
if (LJ_UNLIKELY(!tvisnil(v)))
- lj_err_caller(sbufL(sbuf->sb), LJ_ERR_BUFFER_DUPKEY);
- r = serialize_get(r, sbuf, v);
+ lj_err_caller(sbufL(sbx), LJ_ERR_BUFFER_DUPKEY);
+ r = serialize_get(r, sbx, v);
} while (--nhash);
}
#if LJ_HASFFI
} else if (tp >= SER_TAG_INT64 && tp <= SER_TAG_COMPLEX) {
uint32_t sz = tp == SER_TAG_COMPLEX ? 16 : 8;
GCcdata *cd;
- if (LJ_UNLIKELY(r + sz > e)) goto eob;
- cd = lj_cdata_new_(sbufL(sbuf->sb),
+ if (LJ_UNLIKELY(r + sz > w)) goto eob;
+ cd = lj_cdata_new_(sbufL(sbx),
tp == SER_TAG_INT64 ? CTID_INT64 :
tp == SER_TAG_UINT64 ? CTID_UINT64 : CTID_COMPLEX_DOUBLE,
sz);
if (sz == 16)
((uint64_t *)cdataptr(cd))[1] = lj_bswap64(((uint64_t *)cdataptr(cd))[1]);
#endif
- setcdataV(sbufL(sbuf->sb), o, cd);
+ setcdataV(sbufL(sbx), o, cd);
#endif
} else if (tp <= (LJ_64 ? SER_TAG_LIGHTUD64 : SER_TAG_LIGHTUD32)) {
uintptr_t ud = 0;
if (tp == SER_TAG_LIGHTUD32) {
- if (LJ_UNLIKELY(r + 4 > e)) goto eob;
+ if (LJ_UNLIKELY(r + 4 > w)) goto eob;
ud = (uintptr_t)(LJ_BE ? lj_bswap(lj_getu32(r)) : lj_getu32(r));
r += 4;
}
#if LJ_64
else if (tp == SER_TAG_LIGHTUD64) {
- if (LJ_UNLIKELY(r + 8 > e)) goto eob;
+ if (LJ_UNLIKELY(r + 8 > w)) goto eob;
memcpy(&ud, r, 8); r += 8;
#if LJ_BE
ud = lj_bswap64(ud);
#endif
}
- setrawlightudV(o, lj_lightud_intern(sbufL(sbuf->sb), (void *)ud));
+ setrawlightudV(o, lj_lightud_intern(sbufL(sbx), (void *)ud));
#else
setrawlightudV(o, (void *)ud);
#endif
} else {
- lj_err_callerv(sbufL(sbuf->sb), LJ_ERR_BUFFER_BADDEC, tp);
+ lj_err_callerv(sbufL(sbx), LJ_ERR_BUFFER_BADDEC, tp);
}
return r;
eob:
- lj_err_caller(sbufL(sbuf->sb), LJ_ERR_BUFFER_EOB);
+ lj_err_caller(sbufL(sbx), LJ_ERR_BUFFER_EOB);
return NULL;
}
-StrBuf * LJ_FASTCALL lj_serialize_put(StrBuf *sbuf, cTValue *o)
+SBufExt * LJ_FASTCALL lj_serialize_put(SBufExt *sbx, cTValue *o)
{
- sbuf->depth = LJ_SERIALIZE_DEPTH;
- sbuf->sb->w = serialize_put(sbuf->sb->w, sbuf, o);
- return sbuf;
+ sbx->depth = LJ_SERIALIZE_DEPTH;
+ sbx->w = serialize_put(sbx->w, sbx, o);
+ return sbx;
}
-StrBuf * LJ_FASTCALL lj_serialize_get(StrBuf *sbuf, TValue *o)
+SBufExt * LJ_FASTCALL lj_serialize_get(SBufExt *sbx, TValue *o)
{
- char *r = serialize_get(sbuf->r, sbuf, o);
- if (r != sbuf->sb->w)
- lj_err_caller(sbufL(sbuf->sb), LJ_ERR_BUFFER_LEFTOV);
- sbuf->r = r;
- return sbuf;
+ char *r = serialize_get(sbx->r, sbx, o);
+ if (r != sbx->w)
+ lj_err_caller(sbufL(sbx), LJ_ERR_BUFFER_LEFTOV);
+ sbx->r = r;
+ return sbx;
}
#endif