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make die/warn and other diagnostics go to wherever STDERR happens
[perl5.git] / scope.h
diff --git a/scope.h b/scope.h
index e2e2004..c975cd1 100644 (file)
--- a/scope.h
+++ b/scope.h
-#define SAVEt_ITEM     0
-#define SAVEt_SV       1
-#define SAVEt_AV       2
-#define SAVEt_HV       3
-#define SAVEt_INT      4
-#define SAVEt_I32      5
-#define SAVEt_SPTR     6
-#define SAVEt_HPTR     7
-#define SAVEt_APTR     8
-#define SAVEt_NSTAB    9
-#define SAVEt_SVREF    10
-#define SAVEt_GP       11
-#define SAVEt_FREESV   12
-#define SAVEt_FREEOP   13
-#define SAVEt_FREEPV   14
-#define SAVEt_CLEARSV  15
-#define SAVEt_DELETE   16
-
-#define SSCHECK(need) if (savestack_ix + need > savestack_max) savestack_grow()
-#define SSPUSHINT(i) (savestack[savestack_ix++].any_i32 = (I32)(i))
-#define SSPUSHPTR(p) (savestack[savestack_ix++].any_ptr = (void*)(p))
-#define SSPOPINT (savestack[--savestack_ix].any_i32)
-#define SSPOPPTR (savestack[--savestack_ix].any_ptr)
-
-#define FREE_TMPS() if (tmps_ix > tmps_floor) free_tmps()
-#define LEAVE_SCOPE(old) if (savestack_ix > old) leave_scope(old)
+#define SAVEt_ITEM             0
+#define SAVEt_SV               1
+#define SAVEt_AV               2
+#define SAVEt_HV               3
+#define SAVEt_INT              4
+#define SAVEt_LONG             5
+#define SAVEt_I32              6
+#define SAVEt_IV               7
+#define SAVEt_SPTR             8
+#define SAVEt_APTR             9
+#define SAVEt_HPTR             10
+#define SAVEt_PPTR             11
+#define SAVEt_NSTAB            12
+#define SAVEt_SVREF            13
+#define SAVEt_GP               14
+#define SAVEt_FREESV           15
+#define SAVEt_FREEOP           16
+#define SAVEt_FREEPV           17
+#define SAVEt_CLEARSV          18
+#define SAVEt_DELETE           19
+#define SAVEt_DESTRUCTOR       20
+#define SAVEt_REGCONTEXT       21
+#define SAVEt_STACK_POS                22
+#define SAVEt_I16              23
+#define SAVEt_AELEM            24
+#define SAVEt_HELEM            25
+#define SAVEt_OP               26
+#define SAVEt_HINTS            27
+#define SAVEt_ALLOC            28
+#define SAVEt_GENERIC_SVREF    29
+
+#define SSCHECK(need) if (PL_savestack_ix + need > PL_savestack_max) savestack_grow()
+#define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
+#define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
+#define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
+#define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
+#define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
+#define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
+#define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
+#define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
+#define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
+#define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
+
+#define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
+#define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
+
+#ifdef DEBUGGING
+#define ENTER                                                  \
+    STMT_START {                                               \
+       push_scope();                                           \
+       DEBUG_l(WITH_THR(Perl_deb(aTHX_ "ENTER scope %ld at %s:%d\n",   \
+                   PL_scopestack_ix, __FILE__, __LINE__)));    \
+    } STMT_END
+#define LEAVE                                                  \
+    STMT_START {                                               \
+       DEBUG_l(WITH_THR(Perl_deb(aTHX_ "LEAVE scope %ld at %s:%d\n",   \
+                   PL_scopestack_ix, __FILE__, __LINE__)));    \
+       pop_scope();                                            \
+    } STMT_END
+#else
+#define ENTER push_scope()
+#define LEAVE pop_scope()
+#endif
+#define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
+
+/*
+ * Not using SOFT_CAST on SAVESPTR, SAVEGENERICSV and SAVEFREESV
+ * because these are used for several kinds of pointer values
+ */
+#define SAVEI16(i)     save_I16(SOFT_CAST(I16*)&(i))
+#define SAVEI32(i)     save_I32(SOFT_CAST(I32*)&(i))
+#define SAVEINT(i)     save_int(SOFT_CAST(int*)&(i))
+#define SAVEIV(i)      save_iv(SOFT_CAST(IV*)&(i))
+#define SAVELONG(l)    save_long(SOFT_CAST(long*)&(l))
+#define SAVESPTR(s)    save_sptr((SV**)&(s))
+#define SAVEPPTR(s)    save_pptr(SOFT_CAST(char**)&(s))
+#define SAVEFREESV(s)  save_freesv((SV*)(s))
+#define SAVEFREEOP(o)  save_freeop(SOFT_CAST(OP*)(o))
+#define SAVEFREEPV(p)  save_freepv(SOFT_CAST(char*)(p))
+#define SAVECLEARSV(sv)        save_clearsv(SOFT_CAST(SV**)&(sv))
+#define SAVEGENERICSV(s)       save_generic_svref((SV**)&(s))
+#define SAVEDELETE(h,k,l) \
+         save_delete(SOFT_CAST(HV*)(h), SOFT_CAST(char*)(k), (I32)(l))
+#define CALLDESTRUCTOR (*SSPOPDPTR)
+#define SAVEDESTRUCTOR(f,p) \
+         save_destructor((DESTRUCTORFUNC_t)(f), SOFT_CAST(void*)(p))
+
+#define SAVESTACK_POS() \
+    STMT_START {                               \
+       SSCHECK(2);                             \
+       SSPUSHINT(PL_stack_sp - PL_stack_base); \
+       SSPUSHINT(SAVEt_STACK_POS);             \
+    } STMT_END
+
+#define SAVEOP()       save_op()
+
+#define SAVEHINTS() \
+    STMT_START {                               \
+       if (PL_hints & HINT_LOCALIZE_HH)        \
+           save_hints();                       \
+       else {                                  \
+           SSCHECK(2);                         \
+           SSPUSHINT(PL_hints);                \
+           SSPUSHINT(SAVEt_HINTS);             \
+       }                                       \
+    } STMT_END
+
+/* SSNEW() temporarily allocates a specified number of bytes of data on the
+ * savestack.  It returns an integer index into the savestack, because a
+ * pointer would get broken if the savestack is moved on reallocation.
+ * SSNEWa() works like SSNEW(), but also aligns the data to the specified
+ * number of bytes.  MEM_ALIGNBYTES is perhaps the most useful.  The
+ * alignment will be preserved therough savestack reallocation *only* if
+ * realloc returns data aligned to a size divisible by `align'!
+ *
+ * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
+ */
+
+#define SSNEW(size)             save_alloc(size, 0)
+#define SSNEWa(size,align)     save_alloc(size, \
+    (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
+
+#define SSPTR(off,type)         ((type) ((char*)PL_savestack + off))
+
+/* A jmpenv packages the state required to perform a proper non-local jump.
+ * Note that there is a start_env initialized when perl starts, and top_env
+ * points to this initially, so top_env should always be non-null.
+ *
+ * Existence of a non-null top_env->je_prev implies it is valid to call
+ * longjmp() at that runlevel (we make sure start_env.je_prev is always
+ * null to ensure this).
+ *
+ * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
+ * establish a local jmpenv to handle exception traps.  Care must be taken
+ * to restore the previous value of je_mustcatch before exiting the
+ * stack frame iff JMPENV_PUSH was not called in that stack frame.
+ * GSAR 97-03-27
+ */
+
+struct jmpenv {
+    struct jmpenv *    je_prev;
+    Sigjmp_buf         je_buf;         /* only for use if !je_throw */
+    int                        je_ret;         /* last exception thrown */
+    bool               je_mustcatch;   /* need to call longjmp()? */
+    void               (*je_throw)(int v); /* last for bincompat */
+};
+
+typedef struct jmpenv JMPENV;
+
+/*
+ * Function that catches/throws, and its callback for the
+ *  body of protected processing.
+ */
+typedef void *(CPERLscope(*protect_body_t)) (pTHX_ va_list);
+typedef void *(CPERLscope(*protect_proc_t)) (pTHX_ int *, protect_body_t, ...);
+
+/*
+ * How to build the first jmpenv.
+ *
+ * top_env needs to be non-zero. It points to an area
+ * in which longjmp() stuff is stored, as C callstack
+ * info there at least is thread specific this has to
+ * be per-thread. Otherwise a 'die' in a thread gives
+ * that thread the C stack of last thread to do an eval {}!
+ */
+
+#define JMPENV_BOOTSTRAP \
+    STMT_START {                               \
+       PL_start_env.je_prev = NULL;            \
+       PL_start_env.je_throw = NULL;           \
+       PL_start_env.je_ret = -1;               \
+       PL_start_env.je_mustcatch = TRUE;       \
+       PL_top_env = &PL_start_env;             \
+    } STMT_END
+
+#ifdef OP_IN_REGISTER
+#define OP_REG_TO_MEM  PL_opsave = op
+#define OP_MEM_TO_REG  op = PL_opsave
+#else
+#define OP_REG_TO_MEM  NOOP
+#define OP_MEM_TO_REG  NOOP
+#endif
+
+/*
+ * These exception-handling macros are split up to
+ * ease integration with C++ exceptions.
+ *
+ * To use C++ try+catch to catch Perl exceptions, an extension author
+ * needs to first write an extern "C" function to throw an appropriate
+ * exception object; typically it will be or contain an integer,
+ * because Perl's internals use integers to track exception types:
+ *    extern "C" { static void thrower(int i) { throw i; } }
+ *
+ * Then (as shown below) the author needs to use, not the simple
+ * JMPENV_PUSH, but several of its constitutent macros, to arrange for
+ * the Perl internals to call thrower() rather than longjmp() to
+ * report exceptions:
+ *
+ *    dJMPENV;
+ *    JMPENV_PUSH_INIT(thrower);
+ *    try {
+ *        ... stuff that may throw exceptions ...
+ *    }
+ *    catch (int why) {  // or whatever matches thrower()
+ *        JMPENV_POST_CATCH;
+ *        EXCEPT_SET(why);
+ *        switch (why) {
+ *          ... // handle various Perl exception codes
+ *        }
+ *    }
+ *    JMPENV_POP;  // don't forget this!
+ */
+
+#define dJMPENV                JMPENV cur_env
+
+#define JMPENV_PUSH_INIT_ENV(cur_env,THROWFUNC) \
+    STMT_START {                                       \
+       cur_env.je_throw = (THROWFUNC);                 \
+       cur_env.je_ret = -1;                            \
+       cur_env.je_mustcatch = FALSE;                   \
+       cur_env.je_prev = PL_top_env;                   \
+       PL_top_env = &cur_env;                          \
+       OP_REG_TO_MEM;                                  \
+    } STMT_END
+
+#define JMPENV_PUSH_INIT(THROWFUNC) JMPENV_PUSH_INIT_ENV(cur_env,THROWFUNC) 
+
+#define JMPENV_POST_CATCH_ENV(cur_env) \
+    STMT_START {                                       \
+       OP_MEM_TO_REG;                                  \
+       PL_top_env = &cur_env;                          \
+    } STMT_END
+
+#define JMPENV_POST_CATCH JMPENV_POST_CATCH_ENV(cur_env)
+
+
+#define JMPENV_PUSH_ENV(cur_env,v) \
+    STMT_START {                                       \
+       JMPENV_PUSH_INIT_ENV(cur_env,NULL);                             \
+       EXCEPT_SET_ENV(cur_env,PerlProc_setjmp(cur_env.je_buf, 1));     \
+       JMPENV_POST_CATCH_ENV(cur_env);                         \
+       (v) = EXCEPT_GET_ENV(cur_env);                          \
+    } STMT_END
+
+#define JMPENV_PUSH(v) JMPENV_PUSH_ENV(cur_env,v) 
+
+#define JMPENV_POP_ENV(cur_env) \
+    STMT_START { PL_top_env = cur_env.je_prev; } STMT_END
+
+#define JMPENV_POP  JMPENV_POP_ENV(cur_env) 
+
+#define JMPENV_JUMP(v) \
+    STMT_START {                                               \
+       OP_REG_TO_MEM;                                          \
+       if (PL_top_env->je_prev) {                              \
+           if (PL_top_env->je_throw)                           \
+               PL_top_env->je_throw(v);                        \
+           else                                                \
+               PerlProc_longjmp(PL_top_env->je_buf, (v));      \
+       }                                                       \
+       if ((v) == 2)                                           \
+           PerlProc_exit(STATUS_NATIVE_EXPORT);                \
+       PerlIO_printf(Perl_error_log, "panic: top_env\n");      \
+       PerlProc_exit(1);                                       \
+    } STMT_END
+
+#define EXCEPT_GET_ENV(cur_env)        (cur_env.je_ret)
+#define EXCEPT_GET EXCEPT_GET_ENV(cur_env)
+#define EXCEPT_SET_ENV(cur_env,v)      (cur_env.je_ret = (v))
+#define EXCEPT_SET(v) EXCEPT_SET_ENV(cur_env,v)
+
+#define CATCH_GET      (PL_top_env->je_mustcatch)
+#define CATCH_SET(v)   (PL_top_env->je_mustcatch = (v))
+