better implementation of change#3326; open(local $foo,...) now
[p5sagit/p5-mst-13.2.git] / scope.h
CommitLineData
b9d12d37 1#define SAVEt_ITEM 0
2#define SAVEt_SV 1
3#define SAVEt_AV 2
4#define SAVEt_HV 3
5#define SAVEt_INT 4
6#define SAVEt_LONG 5
7#define SAVEt_I32 6
8#define SAVEt_IV 7
9#define SAVEt_SPTR 8
10#define SAVEt_APTR 9
11#define SAVEt_HPTR 10
12#define SAVEt_PPTR 11
13#define SAVEt_NSTAB 12
14#define SAVEt_SVREF 13
15#define SAVEt_GP 14
16#define SAVEt_FREESV 15
17#define SAVEt_FREEOP 16
18#define SAVEt_FREEPV 17
19#define SAVEt_CLEARSV 18
20#define SAVEt_DELETE 19
21#define SAVEt_DESTRUCTOR 20
22#define SAVEt_REGCONTEXT 21
23#define SAVEt_STACK_POS 22
24#define SAVEt_I16 23
25#define SAVEt_AELEM 24
26#define SAVEt_HELEM 25
27#define SAVEt_OP 26
28#define SAVEt_HINTS 27
29#define SAVEt_ALLOC 28
30#define SAVEt_GENERIC_SVREF 29
c76ac1ee 31#define SAVEt_DESTRUCTOR_X 30
7766f137 32#define SAVEt_VPTR 31
79072805 33
3280af22 34#define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()
35#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
36#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
37#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
38#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
39#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
c76ac1ee 40#define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
3280af22 41#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
42#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
43#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
44#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
45#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
c76ac1ee 46#define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
8990e307 47
3280af22 48#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
49#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
a0d0e21e 50
f46d017c 51#ifdef DEBUGGING
52#define ENTER \
53 STMT_START { \
54 push_scope(); \
cea2e8a9 55 DEBUG_l(WITH_THR(Perl_deb(aTHX_ "ENTER scope %ld at %s:%d\n", \
3280af22 56 PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c 57 } STMT_END
58#define LEAVE \
59 STMT_START { \
cea2e8a9 60 DEBUG_l(WITH_THR(Perl_deb(aTHX_ "LEAVE scope %ld at %s:%d\n", \
3280af22 61 PL_scopestack_ix, __FILE__, __LINE__))); \
f46d017c 62 pop_scope(); \
63 } STMT_END
64#else
a0d0e21e 65#define ENTER push_scope()
66#define LEAVE pop_scope()
f46d017c 67#endif
3280af22 68#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
a0d0e21e 69
55497cff 70/*
b9d12d37 71 * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
55497cff 72 * because these are used for several kinds of pointer values
73 */
4fdae800 74#define SAVEI16(i) save_I16(SOFT_CAST(I16*)&(i))
75#define SAVEI32(i) save_I32(SOFT_CAST(I32*)&(i))
76#define SAVEINT(i) save_int(SOFT_CAST(int*)&(i))
77#define SAVEIV(i) save_iv(SOFT_CAST(IV*)&(i))
78#define SAVELONG(l) save_long(SOFT_CAST(long*)&(l))
55497cff 79#define SAVESPTR(s) save_sptr((SV**)&(s))
80#define SAVEPPTR(s) save_pptr(SOFT_CAST(char**)&(s))
57b2e452 81#define SAVEVPTR(s) save_vptr((void*)&(s))
55497cff 82#define SAVEFREESV(s) save_freesv((SV*)(s))
83#define SAVEFREEOP(o) save_freeop(SOFT_CAST(OP*)(o))
84#define SAVEFREEPV(p) save_freepv(SOFT_CAST(char*)(p))
85#define SAVECLEARSV(sv) save_clearsv(SOFT_CAST(SV**)&(sv))
b9d12d37 86#define SAVEGENERICSV(s) save_generic_svref((SV**)&(s))
55497cff 87#define SAVEDELETE(h,k,l) \
88 save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
89#define SAVEDESTRUCTOR(f,p) \
c76ac1ee 90 save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), SOFT_CAST(void*)(p))
91
92#define SAVEDESTRUCTOR_X(f,p) \
93 save_destructor_x((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
25eaa213 94
95#define SAVESTACK_POS() \
96 STMT_START { \
97 SSCHECK(2); \
3280af22 98 SSPUSHINT(PL_stack_sp - PL_stack_base); \
25eaa213 99 SSPUSHINT(SAVEt_STACK_POS); \
100 } STMT_END
101
462e5cf6 102#define SAVEOP() save_op()
25eaa213 103
104#define SAVEHINTS() \
105 STMT_START { \
3280af22 106 if (PL_hints & HINT_LOCALIZE_HH) \
25eaa213 107 save_hints(); \
108 else { \
109 SSCHECK(2); \
3280af22 110 SSPUSHINT(PL_hints); \
25eaa213 111 SSPUSHINT(SAVEt_HINTS); \
112 } \
113 } STMT_END
a9332b4a 114
57843af0 115#ifdef USE_ITHREADS
11faa288 116# define SAVECOPSTASH(cop) SAVEPPTR(CopSTASHPV(cop))
57843af0 117# define SAVECOPFILE(cop) SAVEPPTR(CopFILE(cop))
118#else
11faa288 119# define SAVECOPSTASH(cop) SAVESPTR(CopSTASH(cop))
57843af0 120# define SAVECOPFILE(cop) SAVESPTR(CopFILEGV(cop))
121#endif
122
123#define SAVECOPLINE(cop) SAVEI16(CopLINE(cop))
124
455ece5e 125/* SSNEW() temporarily allocates a specified number of bytes of data on the
126 * savestack. It returns an integer index into the savestack, because a
127 * pointer would get broken if the savestack is moved on reallocation.
128 * SSNEWa() works like SSNEW(), but also aligns the data to the specified
129 * number of bytes. MEM_ALIGNBYTES is perhaps the most useful. The
130 * alignment will be preserved therough savestack reallocation *only* if
131 * realloc returns data aligned to a size divisible by `align'!
132 *
133 * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
134 */
135
136#define SSNEW(size) save_alloc(size, 0)
137#define SSNEWa(size,align) save_alloc(size, \
138 (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
139
140#define SSPTR(off,type) ((type) ((char*)PL_savestack + off))
141
54310121 142/* A jmpenv packages the state required to perform a proper non-local jump.
143 * Note that there is a start_env initialized when perl starts, and top_env
144 * points to this initially, so top_env should always be non-null.
145 *
146 * Existence of a non-null top_env->je_prev implies it is valid to call
6224f72b 147 * longjmp() at that runlevel (we make sure start_env.je_prev is always
148 * null to ensure this).
54310121 149 *
150 * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
151 * establish a local jmpenv to handle exception traps. Care must be taken
152 * to restore the previous value of je_mustcatch before exiting the
153 * stack frame iff JMPENV_PUSH was not called in that stack frame.
6224f72b 154 * GSAR 97-03-27
54310121 155 */
156
157struct jmpenv {
158 struct jmpenv * je_prev;
312caa8e 159 Sigjmp_buf je_buf; /* only for use if !je_throw */
160 int je_ret; /* last exception thrown */
161 bool je_mustcatch; /* need to call longjmp()? */
162 void (*je_throw)(int v); /* last for bincompat */
db36c5a1 163 bool je_noset; /* no need for setjmp() */
1163b5c4 164};
1163b5c4 165
6224f72b 166typedef struct jmpenv JMPENV;
1163b5c4 167
312caa8e 168/*
169 * Function that catches/throws, and its callback for the
170 * body of protected processing.
171 */
cea2e8a9 172typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list);
db36c5a1 173typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ volatile JMPENV *pcur_env,
174 int *, protect_body_t, ...);
312caa8e 175
176/*
177 * How to build the first jmpenv.
178 *
179 * top_env needs to be non-zero. It points to an area
180 * in which longjmp() stuff is stored, as C callstack
181 * info there at least is thread specific this has to
182 * be per-thread. Otherwise a 'die' in a thread gives
183 * that thread the C stack of last thread to do an eval {}!
184 */
185
186#define JMPENV_BOOTSTRAP \
187 STMT_START { \
188 PL_start_env.je_prev = NULL; \
189 PL_start_env.je_throw = NULL; \
190 PL_start_env.je_ret = -1; \
191 PL_start_env.je_mustcatch = TRUE; \
db36c5a1 192 PL_start_env.je_noset = 0; \
312caa8e 193 PL_top_env = &PL_start_env; \
194 } STMT_END
195
462e5cf6 196#ifdef OP_IN_REGISTER
6b88bc9c 197#define OP_REG_TO_MEM PL_opsave = op
198#define OP_MEM_TO_REG op = PL_opsave
462e5cf6 199#else
200#define OP_REG_TO_MEM NOOP
201#define OP_MEM_TO_REG NOOP
202#endif
203
312caa8e 204/*
205 * These exception-handling macros are split up to
206 * ease integration with C++ exceptions.
207 *
208 * To use C++ try+catch to catch Perl exceptions, an extension author
209 * needs to first write an extern "C" function to throw an appropriate
210 * exception object; typically it will be or contain an integer,
211 * because Perl's internals use integers to track exception types:
212 * extern "C" { static void thrower(int i) { throw i; } }
213 *
214 * Then (as shown below) the author needs to use, not the simple
215 * JMPENV_PUSH, but several of its constitutent macros, to arrange for
216 * the Perl internals to call thrower() rather than longjmp() to
217 * report exceptions:
218 *
219 * dJMPENV;
220 * JMPENV_PUSH_INIT(thrower);
221 * try {
222 * ... stuff that may throw exceptions ...
223 * }
224 * catch (int why) { // or whatever matches thrower()
225 * JMPENV_POST_CATCH;
226 * EXCEPT_SET(why);
227 * switch (why) {
228 * ... // handle various Perl exception codes
229 * }
230 * }
231 * JMPENV_POP; // don't forget this!
232 */
233
db36c5a1 234#define dJMPENV JMPENV cur_env; \
235 volatile JMPENV *pcur_env = ((cur_env.je_noset = 0),&cur_env)
312caa8e 236
db36c5a1 237#define JMPENV_PUSH_INIT_ENV(ce,THROWFUNC) \
6224f72b 238 STMT_START { \
db36c5a1 239 (ce).je_throw = (THROWFUNC); \
240 (ce).je_ret = -1; \
241 (ce).je_mustcatch = FALSE; \
242 (ce).je_prev = PL_top_env; \
243 PL_top_env = &(ce); \
6224f72b 244 OP_REG_TO_MEM; \
312caa8e 245 } STMT_END
1d651c14 246
db36c5a1 247#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(*(JMPENV*)pcur_env,THROWFUNC)
1d651c14 248
db36c5a1 249#define JMPENV_POST_CATCH_ENV(ce) \
312caa8e 250 STMT_START { \
6224f72b 251 OP_MEM_TO_REG; \
db36c5a1 252 PL_top_env = &(ce); \
6224f72b 253 } STMT_END
312caa8e 254
db36c5a1 255#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(*(JMPENV*)pcur_env)
1d651c14 256
257
db36c5a1 258#define JMPENV_PUSH_ENV(ce,v) \
259 STMT_START { \
260 if (!(ce).je_noset) { \
261 JMPENV_PUSH_INIT_ENV(ce,NULL); \
262 EXCEPT_SET_ENV(ce,PerlProc_setjmp((ce).je_buf, 1));\
263 (ce).je_noset = 1; \
264 } \
265 else \
266 EXCEPT_SET_ENV(ce,0); \
267 JMPENV_POST_CATCH_ENV(ce); \
268 (v) = EXCEPT_GET_ENV(ce); \
312caa8e 269 } STMT_END
270
db36c5a1 271#define JMPENV_PUSH(v) JMPENV_PUSH_ENV(*(JMPENV*)pcur_env,v)
1d651c14 272
db36c5a1 273#define JMPENV_POP_ENV(ce) \
274 STMT_START { PL_top_env = (ce).je_prev; } STMT_END
312caa8e 275
db36c5a1 276#define JMPENV_POP JMPENV_POP_ENV(*(JMPENV*)pcur_env)
1d651c14 277
22921e25 278#define JMPENV_JUMP(v) \
279 STMT_START { \
462e5cf6 280 OP_REG_TO_MEM; \
312caa8e 281 if (PL_top_env->je_prev) { \
282 if (PL_top_env->je_throw) \
283 PL_top_env->je_throw(v); \
284 else \
285 PerlProc_longjmp(PL_top_env->je_buf, (v)); \
286 } \
6224f72b 287 if ((v) == 2) \
312caa8e 288 PerlProc_exit(STATUS_NATIVE_EXPORT); \
bf49b057 289 PerlIO_printf(Perl_error_log, "panic: top_env\n"); \
312caa8e 290 PerlProc_exit(1); \
22921e25 291 } STMT_END
312caa8e 292
db36c5a1 293#define EXCEPT_GET_ENV(ce) ((ce).je_ret)
294#define EXCEPT_GET EXCEPT_GET_ENV(*(JMPENV*)pcur_env)
295#define EXCEPT_SET_ENV(ce,v) ((ce).je_ret = (v))
296#define EXCEPT_SET(v) EXCEPT_SET_ENV(*(JMPENV*)pcur_env,v)
312caa8e 297
db36c5a1 298#define CATCH_GET (PL_top_env->je_mustcatch)
299#define CATCH_SET(v) (PL_top_env->je_mustcatch = (v))