diff options
Diffstat (limited to 'libs/luajit-cmake/luajit/src/lj_debug.c')
| -rw-r--r-- | libs/luajit-cmake/luajit/src/lj_debug.c | 705 |
1 files changed, 705 insertions, 0 deletions
diff --git a/libs/luajit-cmake/luajit/src/lj_debug.c b/libs/luajit-cmake/luajit/src/lj_debug.c new file mode 100644 index 0000000..112f535 --- /dev/null +++ b/libs/luajit-cmake/luajit/src/lj_debug.c @@ -0,0 +1,705 @@ +/* +** Debugging and introspection. +** Copyright (C) 2005-2022 Mike Pall. See Copyright Notice in luajit.h +*/ + +#define lj_debug_c +#define LUA_CORE + +#include "lj_obj.h" +#include "lj_err.h" +#include "lj_debug.h" +#include "lj_buf.h" +#include "lj_tab.h" +#include "lj_state.h" +#include "lj_frame.h" +#include "lj_bc.h" +#include "lj_strfmt.h" +#if LJ_HASJIT +#include "lj_jit.h" +#endif + +/* -- Frames -------------------------------------------------------------- */ + +/* Get frame corresponding to a level. */ +cTValue *lj_debug_frame(lua_State *L, int level, int *size) +{ + cTValue *frame, *nextframe, *bot = tvref(L->stack)+LJ_FR2; + /* Traverse frames backwards. */ + for (nextframe = frame = L->base-1; frame > bot; ) { + if (frame_gc(frame) == obj2gco(L)) + level++; /* Skip dummy frames. See lj_err_optype_call(). */ + if (level-- == 0) { + *size = (int)(nextframe - frame); + return frame; /* Level found. */ + } + nextframe = frame; + if (frame_islua(frame)) { + frame = frame_prevl(frame); + } else { + if (frame_isvarg(frame)) + level++; /* Skip vararg pseudo-frame. */ + frame = frame_prevd(frame); + } + } + *size = level; + return NULL; /* Level not found. */ +} + +/* Invalid bytecode position. */ +#define NO_BCPOS (~(BCPos)0) + +/* Return bytecode position for function/frame or NO_BCPOS. */ +static BCPos debug_framepc(lua_State *L, GCfunc *fn, cTValue *nextframe) +{ + const BCIns *ins; + GCproto *pt; + BCPos pos; + lj_assertL(fn->c.gct == ~LJ_TFUNC || fn->c.gct == ~LJ_TTHREAD, + "function or frame expected"); + if (!isluafunc(fn)) { /* Cannot derive a PC for non-Lua functions. */ + return NO_BCPOS; + } else if (nextframe == NULL) { /* Lua function on top. */ + void *cf = cframe_raw(L->cframe); + if (cf == NULL || (char *)cframe_pc(cf) == (char *)cframe_L(cf)) + return NO_BCPOS; + ins = cframe_pc(cf); /* Only happens during error/hook handling. */ + } else { + if (frame_islua(nextframe)) { + ins = frame_pc(nextframe); + } else if (frame_iscont(nextframe)) { + ins = frame_contpc(nextframe); + } else { + /* Lua function below errfunc/gc/hook: find cframe to get the PC. */ + void *cf = cframe_raw(L->cframe); + TValue *f = L->base-1; + for (;;) { + if (cf == NULL) + return NO_BCPOS; + while (cframe_nres(cf) < 0) { + if (f >= restorestack(L, -cframe_nres(cf))) + break; + cf = cframe_raw(cframe_prev(cf)); + if (cf == NULL) + return NO_BCPOS; + } + if (f < nextframe) + break; + if (frame_islua(f)) { + f = frame_prevl(f); + } else { + if (frame_isc(f) || (frame_iscont(f) && frame_iscont_fficb(f))) + cf = cframe_raw(cframe_prev(cf)); + f = frame_prevd(f); + } + } + ins = cframe_pc(cf); + if (!ins) return NO_BCPOS; + } + } + pt = funcproto(fn); + pos = proto_bcpos(pt, ins) - 1; +#if LJ_HASJIT + if (pos > pt->sizebc) { /* Undo the effects of lj_trace_exit for JLOOP. */ + GCtrace *T = (GCtrace *)((char *)(ins-1) - offsetof(GCtrace, startins)); + lj_assertL(bc_isret(bc_op(ins[-1])), "return bytecode expected"); + pos = proto_bcpos(pt, mref(T->startpc, const BCIns)); + } +#endif + return pos; +} + +/* -- Line numbers -------------------------------------------------------- */ + +/* Get line number for a bytecode position. */ +BCLine LJ_FASTCALL lj_debug_line(GCproto *pt, BCPos pc) +{ + const void *lineinfo = proto_lineinfo(pt); + if (pc <= pt->sizebc && lineinfo) { + BCLine first = pt->firstline; + if (pc == pt->sizebc) return first + pt->numline; + if (pc-- == 0) return first; + if (pt->numline < 256) + return first + (BCLine)((const uint8_t *)lineinfo)[pc]; + else if (pt->numline < 65536) + return first + (BCLine)((const uint16_t *)lineinfo)[pc]; + else + return first + (BCLine)((const uint32_t *)lineinfo)[pc]; + } + return 0; +} + +/* Get line number for function/frame. */ +static BCLine debug_frameline(lua_State *L, GCfunc *fn, cTValue *nextframe) +{ + BCPos pc = debug_framepc(L, fn, nextframe); + if (pc != NO_BCPOS) { + GCproto *pt = funcproto(fn); + lj_assertL(pc <= pt->sizebc, "PC out of range"); + return lj_debug_line(pt, pc); + } + return -1; +} + +/* -- Variable names ------------------------------------------------------ */ + +/* Get name of a local variable from slot number and PC. */ +static const char *debug_varname(const GCproto *pt, BCPos pc, BCReg slot) +{ + const char *p = (const char *)proto_varinfo(pt); + if (p) { + BCPos lastpc = 0; + for (;;) { + const char *name = p; + uint32_t vn = *(const uint8_t *)p; + BCPos startpc, endpc; + if (vn < VARNAME__MAX) { + if (vn == VARNAME_END) break; /* End of varinfo. */ + } else { + do { p++; } while (*(const uint8_t *)p); /* Skip over variable name. */ + } + p++; + lastpc = startpc = lastpc + lj_buf_ruleb128(&p); + if (startpc > pc) break; + endpc = startpc + lj_buf_ruleb128(&p); + if (pc < endpc && slot-- == 0) { + if (vn < VARNAME__MAX) { +#define VARNAMESTR(name, str) str "\0" + name = VARNAMEDEF(VARNAMESTR); +#undef VARNAMESTR + if (--vn) while (*name++ || --vn) ; + } + return name; + } + } + } + return NULL; +} + +/* Get name of local variable from 1-based slot number and function/frame. */ +static TValue *debug_localname(lua_State *L, const lua_Debug *ar, + const char **name, BCReg slot1) +{ + uint32_t offset = (uint32_t)ar->i_ci & 0xffff; + uint32_t size = (uint32_t)ar->i_ci >> 16; + TValue *frame = tvref(L->stack) + offset; + TValue *nextframe = size ? frame + size : NULL; + GCfunc *fn = frame_func(frame); + BCPos pc = debug_framepc(L, fn, nextframe); + if (!nextframe) nextframe = L->top+LJ_FR2; + if ((int)slot1 < 0) { /* Negative slot number is for varargs. */ + if (pc != NO_BCPOS) { + GCproto *pt = funcproto(fn); + if ((pt->flags & PROTO_VARARG)) { + slot1 = pt->numparams + (BCReg)(-(int)slot1); + if (frame_isvarg(frame)) { /* Vararg frame has been set up? (pc!=0) */ + nextframe = frame; + frame = frame_prevd(frame); + } + if (frame + slot1+LJ_FR2 < nextframe) { + *name = "(*vararg)"; + return frame+slot1; + } + } + } + return NULL; + } + if (pc != NO_BCPOS && + (*name = debug_varname(funcproto(fn), pc, slot1-1)) != NULL) + ; + else if (slot1 > 0 && frame + slot1+LJ_FR2 < nextframe) + *name = "(*temporary)"; + return frame+slot1; +} + +/* Get name of upvalue. */ +const char *lj_debug_uvname(GCproto *pt, uint32_t idx) +{ + const uint8_t *p = proto_uvinfo(pt); + lj_assertX(idx < pt->sizeuv, "bad upvalue index"); + if (!p) return ""; + if (idx) while (*p++ || --idx) ; + return (const char *)p; +} + +/* Get name and value of upvalue. */ +const char *lj_debug_uvnamev(cTValue *o, uint32_t idx, TValue **tvp, GCobj **op) +{ + if (tvisfunc(o)) { + GCfunc *fn = funcV(o); + if (isluafunc(fn)) { + GCproto *pt = funcproto(fn); + if (idx < pt->sizeuv) { + GCobj *uvo = gcref(fn->l.uvptr[idx]); + *tvp = uvval(&uvo->uv); + *op = uvo; + return lj_debug_uvname(pt, idx); + } + } else { + if (idx < fn->c.nupvalues) { + *tvp = &fn->c.upvalue[idx]; + *op = obj2gco(fn); + return ""; + } + } + } + return NULL; +} + +/* Deduce name of an object from slot number and PC. */ +const char *lj_debug_slotname(GCproto *pt, const BCIns *ip, BCReg slot, + const char **name) +{ + const char *lname; +restart: + lname = debug_varname(pt, proto_bcpos(pt, ip), slot); + if (lname != NULL) { *name = lname; return "local"; } + while (--ip > proto_bc(pt)) { + BCIns ins = *ip; + BCOp op = bc_op(ins); + BCReg ra = bc_a(ins); + if (bcmode_a(op) == BCMbase) { + if (slot >= ra && (op != BC_KNIL || slot <= bc_d(ins))) + return NULL; + } else if (bcmode_a(op) == BCMdst && ra == slot) { + switch (bc_op(ins)) { + case BC_MOV: + if (ra == slot) { slot = bc_d(ins); goto restart; } + break; + case BC_GGET: + *name = strdata(gco2str(proto_kgc(pt, ~(ptrdiff_t)bc_d(ins)))); + return "global"; + case BC_TGETS: + *name = strdata(gco2str(proto_kgc(pt, ~(ptrdiff_t)bc_c(ins)))); + if (ip > proto_bc(pt)) { + BCIns insp = ip[-1]; + if (bc_op(insp) == BC_MOV && bc_a(insp) == ra+1+LJ_FR2 && + bc_d(insp) == bc_b(ins)) + return "method"; + } + return "field"; + case BC_UGET: + *name = lj_debug_uvname(pt, bc_d(ins)); + return "upvalue"; + default: + return NULL; + } + } + } + return NULL; +} + +/* Deduce function name from caller of a frame. */ +const char *lj_debug_funcname(lua_State *L, cTValue *frame, const char **name) +{ + cTValue *pframe; + GCfunc *fn; + BCPos pc; + if (frame <= tvref(L->stack)+LJ_FR2) + return NULL; + if (frame_isvarg(frame)) + frame = frame_prevd(frame); + pframe = frame_prev(frame); + fn = frame_func(pframe); + pc = debug_framepc(L, fn, frame); + if (pc != NO_BCPOS) { + GCproto *pt = funcproto(fn); + const BCIns *ip = &proto_bc(pt)[check_exp(pc < pt->sizebc, pc)]; + MMS mm = bcmode_mm(bc_op(*ip)); + if (mm == MM_call) { + BCReg slot = bc_a(*ip); + if (bc_op(*ip) == BC_ITERC) slot -= 3; + return lj_debug_slotname(pt, ip, slot, name); + } else if (mm != MM__MAX) { + *name = strdata(mmname_str(G(L), mm)); + return "metamethod"; + } + } + return NULL; +} + +/* -- Source code locations ----------------------------------------------- */ + +/* Generate shortened source name. */ +void lj_debug_shortname(char *out, GCstr *str, BCLine line) +{ + const char *src = strdata(str); + if (*src == '=') { + strncpy(out, src+1, LUA_IDSIZE); /* Remove first char. */ + out[LUA_IDSIZE-1] = '\0'; /* Ensures null termination. */ + } else if (*src == '@') { /* Output "source", or "...source". */ + size_t len = str->len-1; + src++; /* Skip the `@' */ + if (len >= LUA_IDSIZE) { + src += len-(LUA_IDSIZE-4); /* Get last part of file name. */ + *out++ = '.'; *out++ = '.'; *out++ = '.'; + } + strcpy(out, src); + } else { /* Output [string "string"] or [builtin:name]. */ + size_t len; /* Length, up to first control char. */ + for (len = 0; len < LUA_IDSIZE-12; len++) + if (((const unsigned char *)src)[len] < ' ') break; + strcpy(out, line == ~(BCLine)0 ? "[builtin:" : "[string \""); out += 9; + if (src[len] != '\0') { /* Must truncate? */ + if (len > LUA_IDSIZE-15) len = LUA_IDSIZE-15; + strncpy(out, src, len); out += len; + strcpy(out, "..."); out += 3; + } else { + strcpy(out, src); out += len; + } + strcpy(out, line == ~(BCLine)0 ? "]" : "\"]"); + } +} + +/* Add current location of a frame to error message. */ +void lj_debug_addloc(lua_State *L, const char *msg, + cTValue *frame, cTValue *nextframe) +{ + if (frame) { + GCfunc *fn = frame_func(frame); + if (isluafunc(fn)) { + BCLine line = debug_frameline(L, fn, nextframe); + if (line >= 0) { + GCproto *pt = funcproto(fn); + char buf[LUA_IDSIZE]; + lj_debug_shortname(buf, proto_chunkname(pt), pt->firstline); + lj_strfmt_pushf(L, "%s:%d: %s", buf, line, msg); + return; + } + } + } + lj_strfmt_pushf(L, "%s", msg); +} + +/* Push location string for a bytecode position to Lua stack. */ +void lj_debug_pushloc(lua_State *L, GCproto *pt, BCPos pc) +{ + GCstr *name = proto_chunkname(pt); + const char *s = strdata(name); + MSize i, len = name->len; + BCLine line = lj_debug_line(pt, pc); + if (pt->firstline == ~(BCLine)0) { + lj_strfmt_pushf(L, "builtin:%s", s); + } else if (*s == '@') { + s++; len--; + for (i = len; i > 0; i--) + if (s[i] == '/' || s[i] == '\\') { + s += i+1; + break; + } + lj_strfmt_pushf(L, "%s:%d", s, line); + } else if (len > 40) { + lj_strfmt_pushf(L, "%p:%d", pt, line); + } else if (*s == '=') { + lj_strfmt_pushf(L, "%s:%d", s+1, line); + } else { + lj_strfmt_pushf(L, "\"%s\":%d", s, line); + } +} + +/* -- Public debug API ---------------------------------------------------- */ + +/* lua_getupvalue() and lua_setupvalue() are in lj_api.c. */ + +LUA_API const char *lua_getlocal(lua_State *L, const lua_Debug *ar, int n) +{ + const char *name = NULL; + if (ar) { + TValue *o = debug_localname(L, ar, &name, (BCReg)n); + if (name) { + copyTV(L, L->top, o); + incr_top(L); + } + } else if (tvisfunc(L->top-1) && isluafunc(funcV(L->top-1))) { + name = debug_varname(funcproto(funcV(L->top-1)), 0, (BCReg)n-1); + } + return name; +} + +LUA_API const char *lua_setlocal(lua_State *L, const lua_Debug *ar, int n) +{ + const char *name = NULL; + TValue *o = debug_localname(L, ar, &name, (BCReg)n); + if (name) + copyTV(L, o, L->top-1); + L->top--; + return name; +} + +int lj_debug_getinfo(lua_State *L, const char *what, lj_Debug *ar, int ext) +{ + int opt_f = 0, opt_L = 0; + TValue *frame = NULL; + TValue *nextframe = NULL; + GCfunc *fn; + if (*what == '>') { + TValue *func = L->top - 1; + if (!tvisfunc(func)) return 0; + fn = funcV(func); + L->top--; + what++; + } else { + uint32_t offset = (uint32_t)ar->i_ci & 0xffff; + uint32_t size = (uint32_t)ar->i_ci >> 16; + lj_assertL(offset != 0, "bad frame offset"); + frame = tvref(L->stack) + offset; + if (size) nextframe = frame + size; + lj_assertL(frame <= tvref(L->maxstack) && + (!nextframe || nextframe <= tvref(L->maxstack)), + "broken frame chain"); + fn = frame_func(frame); + lj_assertL(fn->c.gct == ~LJ_TFUNC, "bad frame function"); + } + for (; *what; what++) { + if (*what == 'S') { + if (isluafunc(fn)) { + GCproto *pt = funcproto(fn); + BCLine firstline = pt->firstline; + GCstr *name = proto_chunkname(pt); + ar->source = strdata(name); + lj_debug_shortname(ar->short_src, name, pt->firstline); + ar->linedefined = (int)firstline; + ar->lastlinedefined = (int)(firstline + pt->numline); + ar->what = (firstline || !pt->numline) ? "Lua" : "main"; + } else { + ar->source = "=[C]"; + ar->short_src[0] = '['; + ar->short_src[1] = 'C'; + ar->short_src[2] = ']'; + ar->short_src[3] = '\0'; + ar->linedefined = -1; + ar->lastlinedefined = -1; + ar->what = "C"; + } + } else if (*what == 'l') { + ar->currentline = frame ? debug_frameline(L, fn, nextframe) : -1; + } else if (*what == 'u') { + ar->nups = fn->c.nupvalues; + if (ext) { + if (isluafunc(fn)) { + GCproto *pt = funcproto(fn); + ar->nparams = pt->numparams; + ar->isvararg = !!(pt->flags & PROTO_VARARG); + } else { + ar->nparams = 0; + ar->isvararg = 1; + } + } + } else if (*what == 'n') { + ar->namewhat = frame ? lj_debug_funcname(L, frame, &ar->name) : NULL; + if (ar->namewhat == NULL) { + ar->namewhat = ""; + ar->name = NULL; + } + } else if (*what == 'f') { + opt_f = 1; + } else if (*what == 'L') { + opt_L = 1; + } else { + return 0; /* Bad option. */ + } + } + if (opt_f) { + setfuncV(L, L->top, fn); + incr_top(L); + } + if (opt_L) { + if (isluafunc(fn)) { + GCtab *t = lj_tab_new(L, 0, 0); + GCproto *pt = funcproto(fn); + const void *lineinfo = proto_lineinfo(pt); + if (lineinfo) { + BCLine first = pt->firstline; + int sz = pt->numline < 256 ? 1 : pt->numline < 65536 ? 2 : 4; + MSize i, szl = pt->sizebc-1; + for (i = 0; i < szl; i++) { + BCLine line = first + + (sz == 1 ? (BCLine)((const uint8_t *)lineinfo)[i] : + sz == 2 ? (BCLine)((const uint16_t *)lineinfo)[i] : + (BCLine)((const uint32_t *)lineinfo)[i]); + setboolV(lj_tab_setint(L, t, line), 1); + } + } + settabV(L, L->top, t); + } else { + setnilV(L->top); + } + incr_top(L); + } + return 1; /* Ok. */ +} + +LUA_API int lua_getinfo(lua_State *L, const char *what, lua_Debug *ar) +{ + return lj_debug_getinfo(L, what, (lj_Debug *)ar, 0); +} + +LUA_API int lua_getstack(lua_State *L, int level, lua_Debug *ar) +{ + int size; + cTValue *frame = lj_debug_frame(L, level, &size); + if (frame) { + ar->i_ci = (size << 16) + (int)(frame - tvref(L->stack)); + return 1; + } else { + ar->i_ci = level - size; + return 0; + } +} + +#if LJ_HASPROFILE +/* Put the chunkname into a buffer. */ +static int debug_putchunkname(SBuf *sb, GCproto *pt, int pathstrip) +{ + GCstr *name = proto_chunkname(pt); + const char *p = strdata(name); + if (pt->firstline == ~(BCLine)0) { + lj_buf_putmem(sb, "[builtin:", 9); + lj_buf_putstr(sb, name); + lj_buf_putb(sb, ']'); + return 0; + } + if (*p == '=' || *p == '@') { + MSize len = name->len-1; + p++; + if (pathstrip) { + int i; + for (i = len-1; i >= 0; i--) + if (p[i] == '/' || p[i] == '\\') { + len -= i+1; + p = p+i+1; + break; + } + } + lj_buf_putmem(sb, p, len); + } else { + lj_buf_putmem(sb, "[string]", 8); + } + return 1; +} + +/* Put a compact stack dump into a buffer. */ +void lj_debug_dumpstack(lua_State *L, SBuf *sb, const char *fmt, int depth) +{ + int level = 0, dir = 1, pathstrip = 1; + MSize lastlen = 0; + if (depth < 0) { level = ~depth; depth = dir = -1; } /* Reverse frames. */ + while (level != depth) { /* Loop through all frame. */ + int size; + cTValue *frame = lj_debug_frame(L, level, &size); + if (frame) { + cTValue *nextframe = size ? frame+size : NULL; + GCfunc *fn = frame_func(frame); + const uint8_t *p = (const uint8_t *)fmt; + int c; + while ((c = *p++)) { + switch (c) { + case 'p': /* Preserve full path. */ + pathstrip = 0; + break; + case 'F': case 'f': { /* Dump function name. */ + const char *name; + const char *what = lj_debug_funcname(L, frame, &name); + if (what) { + if (c == 'F' && isluafunc(fn)) { /* Dump module:name for 'F'. */ + GCproto *pt = funcproto(fn); + if (pt->firstline != ~(BCLine)0) { /* Not a bytecode builtin. */ + debug_putchunkname(sb, pt, pathstrip); + lj_buf_putb(sb, ':'); + } + } + lj_buf_putmem(sb, name, (MSize)strlen(name)); + break; + } /* else: can't derive a name, dump module:line. */ + } + /* fallthrough */ + case 'l': /* Dump module:line. */ + if (isluafunc(fn)) { + GCproto *pt = funcproto(fn); + if (debug_putchunkname(sb, pt, pathstrip)) { + /* Regular Lua function. */ + BCLine line = c == 'l' ? debug_frameline(L, fn, nextframe) : + pt->firstline; + lj_buf_putb(sb, ':'); + lj_strfmt_putint(sb, line >= 0 ? line : pt->firstline); + } + } else if (isffunc(fn)) { /* Dump numbered builtins. */ + lj_buf_putmem(sb, "[builtin#", 9); + lj_strfmt_putint(sb, fn->c.ffid); + lj_buf_putb(sb, ']'); + } else { /* Dump C function address. */ + lj_buf_putb(sb, '@'); + lj_strfmt_putptr(sb, fn->c.f); + } + break; + case 'Z': /* Zap trailing separator. */ + lastlen = sbuflen(sb); + break; + default: + lj_buf_putb(sb, c); + break; + } + } + } else if (dir == 1) { + break; + } else { + level -= size; /* Reverse frame order: quickly skip missing level. */ + } + level += dir; + } + if (lastlen) + sb->w = sb->b + lastlen; /* Zap trailing separator. */ +} +#endif + +/* Number of frames for the leading and trailing part of a traceback. */ +#define TRACEBACK_LEVELS1 12 +#define TRACEBACK_LEVELS2 10 + +LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1, const char *msg, + int level) +{ + int top = (int)(L->top - L->base); + int lim = TRACEBACK_LEVELS1; + lua_Debug ar; + if (msg) lua_pushfstring(L, "%s\n", msg); + lua_pushliteral(L, "stack traceback:"); + while (lua_getstack(L1, level++, &ar)) { + GCfunc *fn; + if (level > lim) { + if (!lua_getstack(L1, level + TRACEBACK_LEVELS2, &ar)) { + level--; + } else { + lua_pushliteral(L, "\n\t..."); + lua_getstack(L1, -10, &ar); + level = ar.i_ci - TRACEBACK_LEVELS2; + } + lim = 2147483647; + continue; + } + lua_getinfo(L1, "Snlf", &ar); + fn = funcV(L1->top-1); L1->top--; + if (isffunc(fn) && !*ar.namewhat) + lua_pushfstring(L, "\n\t[builtin#%d]:", fn->c.ffid); + else + lua_pushfstring(L, "\n\t%s:", ar.short_src); + if (ar.currentline > 0) + lua_pushfstring(L, "%d:", ar.currentline); + if (*ar.namewhat) { + lua_pushfstring(L, " in function " LUA_QS, ar.name); + } else { + if (*ar.what == 'm') { + lua_pushliteral(L, " in main chunk"); + } else if (*ar.what == 'C') { + lua_pushfstring(L, " at %p", fn->c.f); + } else { + lua_pushfstring(L, " in function <%s:%d>", + ar.short_src, ar.linedefined); + } + } + if ((int)(L->top - L->base) - top >= 15) + lua_concat(L, (int)(L->top - L->base) - top); + } + lua_concat(L, (int)(L->top - L->base) - top); +} + |