Fix for environment leak
[perl.git] / cop.h
1 /*    cop.h
2  *
3  *    Copyright (c) 1991-1997, Larry Wall
4  *
5  *    You may distribute under the terms of either the GNU General Public
6  *    License or the Artistic License, as specified in the README file.
7  *
8  */
9
10 struct cop {
11     BASEOP
12     char *      cop_label;      /* label for this construct */
13     HV *        cop_stash;      /* package line was compiled in */
14     GV *        cop_filegv;     /* file the following line # is from */
15     U32         cop_seq;        /* parse sequence number */
16     I32         cop_arybase;    /* array base this line was compiled with */
17     line_t      cop_line;       /* line # of this command */
18 };
19
20 #define Nullcop Null(COP*)
21
22 /*
23  * Here we have some enormously heavy (or at least ponderous) wizardry.
24  */
25
26 /* subroutine context */
27 struct block_sub {
28     CV *        cv;
29     GV *        gv;
30     GV *        dfoutgv;
31     AV *        savearray;
32     AV *        argarray;
33     U16         olddepth;
34     U8          hasargs;
35 };
36
37 #define PUSHSUB(cx)                                                     \
38         cx->blk_sub.cv = cv;                                            \
39         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
40         cx->blk_sub.hasargs = hasargs;
41
42 #define PUSHFORMAT(cx)                                                  \
43         cx->blk_sub.cv = cv;                                            \
44         cx->blk_sub.gv = gv;                                            \
45         cx->blk_sub.hasargs = 0;                                        \
46         cx->blk_sub.dfoutgv = defoutgv;                                 \
47         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
48
49 #define POPSUB(cx)                                                      \
50         { struct block_sub cxsub;                                       \
51           POPSUB1(cx);                                                  \
52           POPSUB2(); }
53
54 #define POPSUB1(cx)                                                     \
55         cxsub = cx->blk_sub;    /* because DESTROY may clobber *cx */
56
57 #define POPSUB2()                                                       \
58         if (cxsub.hasargs) {                                            \
59             /* put back old @_ */                                       \
60             SvREFCNT_dec(GvAV(defgv));                                  \
61             GvAV(defgv) = cxsub.savearray;                              \
62             /* destroy arg array */                                     \
63             av_clear(cxsub.argarray);                                   \
64             AvREAL_off(cxsub.argarray);                                 \
65         }                                                               \
66         if (cxsub.cv) {                                                 \
67             if (!(CvDEPTH(cxsub.cv) = cxsub.olddepth))                  \
68                 SvREFCNT_dec(cxsub.cv);                                 \
69         }
70
71 #define POPFORMAT(cx)                                                   \
72         setdefout(cx->blk_sub.dfoutgv);                                 \
73         SvREFCNT_dec(cx->blk_sub.dfoutgv);
74
75 /* eval context */
76 struct block_eval {
77     I32         old_in_eval;
78     I32         old_op_type;
79     char *      old_name;
80     OP *        old_eval_root;
81     SV *        cur_text;
82 };
83
84 #define PUSHEVAL(cx,n,fgv)                                              \
85         cx->blk_eval.old_in_eval = in_eval;                             \
86         cx->blk_eval.old_op_type = op->op_type;                         \
87         cx->blk_eval.old_name = n;                                      \
88         cx->blk_eval.old_eval_root = eval_root;                         \
89         cx->blk_eval.cur_text = linestr;
90
91 #define POPEVAL(cx)                                                     \
92         in_eval = cx->blk_eval.old_in_eval;                             \
93         optype = cx->blk_eval.old_op_type;                              \
94         eval_root = cx->blk_eval.old_eval_root;
95
96 /* loop context */
97 struct block_loop {
98     char *      label;
99     I32         resetsp;
100     OP *        redo_op;
101     OP *        next_op;
102     OP *        last_op;
103     SV **       itervar;
104     SV *        itersave;
105     SV *        iterlval;
106     AV *        iterary;
107     I32         iterix;
108 };
109
110 #define PUSHLOOP(cx, ivar, s)                                           \
111         cx->blk_loop.label = curcop->cop_label;                         \
112         cx->blk_loop.resetsp = s - stack_base;                          \
113         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
114         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
115         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
116         if (cx->blk_loop.itervar = (ivar))                              \
117             cx->blk_loop.itersave = SvREFCNT_inc(*cx->blk_loop.itervar);\
118         cx->blk_loop.iterlval = Nullsv;                                 \
119         cx->blk_loop.iterary = Nullav;                                  \
120         cx->blk_loop.iterix = -1;
121
122 #define POPLOOP(cx)                                                     \
123         { struct block_loop cxloop;                                     \
124           POPLOOP1(cx);                                                 \
125           POPLOOP2(); }
126
127 #define POPLOOP1(cx)                                                    \
128         cxloop = cx->blk_loop;  /* because DESTROY may clobber *cx */   \
129         newsp = stack_base + cxloop.resetsp;
130
131 #define POPLOOP2()                                                      \
132         SvREFCNT_dec(cxloop.iterlval);                                  \
133         if (cxloop.itervar) {                                           \
134             SvREFCNT_dec(*cxloop.itervar);                              \
135             *cxloop.itervar = cxloop.itersave;                          \
136         }                                                               \
137         if (cxloop.iterary && cxloop.iterary != curstack)               \
138             SvREFCNT_dec(cxloop.iterary);
139
140 /* context common to subroutines, evals and loops */
141 struct block {
142     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
143     COP *       blku_oldcop;    /* old curcop pointer */
144     I32         blku_oldretsp;  /* return stack index */
145     I32         blku_oldmarksp; /* mark stack index */
146     I32         blku_oldscopesp;        /* scope stack index */
147     PMOP *      blku_oldpm;     /* values of pattern match vars */
148     U8          blku_gimme;     /* is this block running in list context? */
149
150     union {
151         struct block_sub        blku_sub;
152         struct block_eval       blku_eval;
153         struct block_loop       blku_loop;
154     } blk_u;
155 };
156 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
157 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
158 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
159 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
160 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
161 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
162 #define blk_gimme       cx_u.cx_blk.blku_gimme
163 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
164 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
165 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
166
167 /* Enter a block. */
168 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
169         cx->cx_type             = t,                                    \
170         cx->blk_oldsp           = sp - stack_base,                      \
171         cx->blk_oldcop          = curcop,                               \
172         cx->blk_oldmarksp       = markstack_ptr - markstack,            \
173         cx->blk_oldscopesp      = scopestack_ix,                        \
174         cx->blk_oldretsp        = retstack_ix,                          \
175         cx->blk_oldpm           = curpm,                                \
176         cx->blk_gimme           = gimme;                                \
177         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Entering block %ld, type %s\n",        \
178                     (long)cxstack_ix, block_type[t]); )
179
180 /* Exit a block (RETURN and LAST). */
181 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
182         newsp           = stack_base + cx->blk_oldsp,                   \
183         curcop          = cx->blk_oldcop,                               \
184         markstack_ptr   = markstack + cx->blk_oldmarksp,                \
185         scopestack_ix   = cx->blk_oldscopesp,                           \
186         retstack_ix     = cx->blk_oldretsp,                             \
187         pm              = cx->blk_oldpm,                                \
188         gimme           = cx->blk_gimme;                                \
189         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Leaving block %ld, type %s\n",         \
190                     (long)cxstack_ix+1,block_type[cx->cx_type]); )
191
192 /* Continue a block elsewhere (NEXT and REDO). */
193 #define TOPBLOCK(cx) cx = &cxstack[cxstack_ix],                         \
194         stack_sp        = stack_base + cx->blk_oldsp,                   \
195         markstack_ptr   = markstack + cx->blk_oldmarksp,                \
196         scopestack_ix   = cx->blk_oldscopesp,                           \
197         retstack_ix     = cx->blk_oldretsp
198
199 /* substitution context */
200 struct subst {
201     I32         sbu_iters;
202     I32         sbu_maxiters;
203     I32         sbu_safebase;
204     I32         sbu_oldsave;
205     bool        sbu_once;
206     bool        sbu_rxtainted;
207     char *      sbu_orig;
208     SV *        sbu_dstr;
209     SV *        sbu_targ;
210     char *      sbu_s;
211     char *      sbu_m;
212     char *      sbu_strend;
213     char *      sbu_subbase;
214     REGEXP *    sbu_rx;
215 };
216 #define sb_iters        cx_u.cx_subst.sbu_iters
217 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
218 #define sb_safebase     cx_u.cx_subst.sbu_safebase
219 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
220 #define sb_once         cx_u.cx_subst.sbu_once
221 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
222 #define sb_orig         cx_u.cx_subst.sbu_orig
223 #define sb_dstr         cx_u.cx_subst.sbu_dstr
224 #define sb_targ         cx_u.cx_subst.sbu_targ
225 #define sb_s            cx_u.cx_subst.sbu_s
226 #define sb_m            cx_u.cx_subst.sbu_m
227 #define sb_strend       cx_u.cx_subst.sbu_strend
228 #define sb_subbase      cx_u.cx_subst.sbu_subbase
229 #define sb_rx           cx_u.cx_subst.sbu_rx
230
231 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
232         cx->sb_iters            = iters,                                \
233         cx->sb_maxiters         = maxiters,                             \
234         cx->sb_safebase         = safebase,                             \
235         cx->sb_oldsave          = oldsave,                              \
236         cx->sb_once             = once,                                 \
237         cx->sb_rxtainted        = rxtainted,                            \
238         cx->sb_orig             = orig,                                 \
239         cx->sb_dstr             = dstr,                                 \
240         cx->sb_targ             = targ,                                 \
241         cx->sb_s                = s,                                    \
242         cx->sb_m                = m,                                    \
243         cx->sb_strend           = strend,                               \
244         cx->sb_subbase          = Nullch,                               \
245         cx->sb_rx               = rx,                                   \
246         cx->cx_type             = CXt_SUBST
247
248 #define POPSUBST(cx) cxstack_ix--
249
250 struct context {
251     I32         cx_type;        /* what kind of context this is */
252     union {
253         struct block    cx_blk;
254         struct subst    cx_subst;
255     } cx_u;
256 };
257 #define CXt_NULL        0
258 #define CXt_SUB         1
259 #define CXt_EVAL        2
260 #define CXt_LOOP        3
261 #define CXt_SUBST       4
262 #define CXt_BLOCK       5
263
264 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
265
266 /* "gimme" values */
267 #define G_SCALAR        0
268 #define G_ARRAY         1
269 #define G_VOID          128     /* skip this bit when adding flags below */
270
271 /* extra flags for perl_call_* routines */
272 #define G_DISCARD       2       /* Call FREETMPS. */
273 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
274 #define G_NOARGS        8       /* Don't construct a @_ array. */
275 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */