xref: /openbsd/gnu/usr.bin/perl/deb.c (revision 17df1aa7)
1 /*    deb.c
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
4  *    2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10 
11 /*
12  * 'Didst thou think that the eyes of the White Tower were blind?  Nay,
13  *  I have seen more than thou knowest, Grey Fool.'        --Denethor
14  *
15  *     [p.853 of _The Lord of the Rings_, V/vii: "The Pyre of Denethor"]
16  */
17 
18 /*
19  * This file contains various utilities for producing debugging output
20  * (mainly related to displaying the stack)
21  */
22 
23 #include "EXTERN.h"
24 #define PERL_IN_DEB_C
25 #include "perl.h"
26 
27 #if defined(PERL_IMPLICIT_CONTEXT)
28 void
29 Perl_deb_nocontext(const char *pat, ...)
30 {
31 #ifdef DEBUGGING
32     dTHX;
33     va_list args;
34     PERL_ARGS_ASSERT_DEB_NOCONTEXT;
35     va_start(args, pat);
36     vdeb(pat, &args);
37     va_end(args);
38 #else
39     PERL_UNUSED_ARG(pat);
40 #endif /* DEBUGGING */
41 }
42 #endif
43 
44 void
45 Perl_deb(pTHX_ const char *pat, ...)
46 {
47     va_list args;
48     PERL_ARGS_ASSERT_DEB;
49     va_start(args, pat);
50 #ifdef DEBUGGING
51     vdeb(pat, &args);
52 #else
53     PERL_UNUSED_CONTEXT;
54 #endif /* DEBUGGING */
55     va_end(args);
56 }
57 
58 void
59 Perl_vdeb(pTHX_ const char *pat, va_list *args)
60 {
61 #ifdef DEBUGGING
62     dVAR;
63     const char* const file = PL_curcop ? OutCopFILE(PL_curcop) : "<null>";
64     const char* const display_file = file ? file : "<free>";
65     const long line = PL_curcop ? (long)CopLINE(PL_curcop) : 0;
66 
67     PERL_ARGS_ASSERT_VDEB;
68 
69     if (DEBUG_v_TEST)
70 	PerlIO_printf(Perl_debug_log, "(%ld:%s:%ld)\t",
71 		      (long)PerlProc_getpid(), display_file, line);
72     else
73 	PerlIO_printf(Perl_debug_log, "(%s:%ld)\t", display_file, line);
74     (void) PerlIO_vprintf(Perl_debug_log, pat, *args);
75 #else
76     PERL_UNUSED_CONTEXT;
77     PERL_UNUSED_ARG(pat);
78     PERL_UNUSED_ARG(args);
79 #endif /* DEBUGGING */
80 }
81 
82 I32
83 Perl_debstackptrs(pTHX)
84 {
85 #ifdef DEBUGGING
86     dVAR;
87     PerlIO_printf(Perl_debug_log,
88 		  "%8"UVxf" %8"UVxf" %8"IVdf" %8"IVdf" %8"IVdf"\n",
89 		  PTR2UV(PL_curstack), PTR2UV(PL_stack_base),
90 		  (IV)*PL_markstack_ptr, (IV)(PL_stack_sp-PL_stack_base),
91 		  (IV)(PL_stack_max-PL_stack_base));
92     PerlIO_printf(Perl_debug_log,
93 		  "%8"UVxf" %8"UVxf" %8"UVuf" %8"UVuf" %8"UVuf"\n",
94 		  PTR2UV(PL_mainstack), PTR2UV(AvARRAY(PL_curstack)),
95 		  PTR2UV(PL_mainstack), PTR2UV(AvFILLp(PL_curstack)),
96 		  PTR2UV(AvMAX(PL_curstack)));
97 #endif /* DEBUGGING */
98     return 0;
99 }
100 
101 
102 /* dump the contents of a particular stack
103  * Display stack_base[stack_min+1 .. stack_max],
104  * and display the marks whose offsets are contained in addresses
105  * PL_markstack[mark_min+1 .. mark_max] and whose values are in the range
106  * of the stack values being displayed
107  *
108  * Only displays top 30 max
109  */
110 
111 STATIC void
112 S_deb_stack_n(pTHX_ SV** stack_base, I32 stack_min, I32 stack_max,
113 	I32 mark_min, I32 mark_max)
114 {
115 #ifdef DEBUGGING
116     dVAR;
117     register I32 i = stack_max - 30;
118     const I32 *markscan = PL_markstack + mark_min;
119 
120     PERL_ARGS_ASSERT_DEB_STACK_N;
121 
122     if (i < stack_min)
123 	i = stack_min;
124 
125     while (++markscan <= PL_markstack + mark_max)
126 	if (*markscan >= i)
127 	    break;
128 
129     if (i > stack_min)
130 	PerlIO_printf(Perl_debug_log, "... ");
131 
132     if (stack_base[0] != &PL_sv_undef || stack_max < 0)
133 	PerlIO_printf(Perl_debug_log, " [STACK UNDERFLOW!!!]\n");
134     do {
135 	++i;
136 	if (markscan <= PL_markstack + mark_max && *markscan < i) {
137 	    do {
138 		++markscan;
139 		PerlIO_putc(Perl_debug_log, '*');
140 	    }
141 	    while (markscan <= PL_markstack + mark_max && *markscan < i);
142 	    PerlIO_printf(Perl_debug_log, "  ");
143 	}
144 	if (i > stack_max)
145 	    break;
146 	PerlIO_printf(Perl_debug_log, "%-4s  ", SvPEEK(stack_base[i]));
147     }
148     while (1);
149     PerlIO_printf(Perl_debug_log, "\n");
150 #else
151     PERL_UNUSED_CONTEXT;
152     PERL_UNUSED_ARG(stack_base);
153     PERL_UNUSED_ARG(stack_min);
154     PERL_UNUSED_ARG(stack_max);
155     PERL_UNUSED_ARG(mark_min);
156     PERL_UNUSED_ARG(mark_max);
157 #endif /* DEBUGGING */
158 }
159 
160 
161 /* dump the current stack */
162 
163 I32
164 Perl_debstack(pTHX)
165 {
166 #ifndef SKIP_DEBUGGING
167     dVAR;
168     if (CopSTASH_eq(PL_curcop, PL_debstash) && !DEBUG_J_TEST_)
169 	return 0;
170 
171     PerlIO_printf(Perl_debug_log, "    =>  ");
172     deb_stack_n(PL_stack_base,
173 		0,
174 		PL_stack_sp - PL_stack_base,
175 		PL_curstackinfo->si_markoff,
176 		PL_markstack_ptr - PL_markstack);
177 
178 
179 #endif /* SKIP_DEBUGGING */
180     return 0;
181 }
182 
183 
184 #ifdef DEBUGGING
185 static const char * const si_names[] = {
186     "UNKNOWN",
187     "UNDEF",
188     "MAIN",
189     "MAGIC",
190     "SORT",
191     "SIGNAL",
192     "OVERLOAD",
193     "DESTROY",
194     "WARNHOOK",
195     "DIEHOOK",
196     "REQUIRE"
197 };
198 #endif
199 
200 /* display all stacks */
201 
202 
203 void
204 Perl_deb_stack_all(pTHX)
205 {
206 #ifdef DEBUGGING
207     dVAR;
208     I32 si_ix;
209     const PERL_SI *si;
210 
211     /* rewind to start of chain */
212     si = PL_curstackinfo;
213     while (si->si_prev)
214 	si = si->si_prev;
215 
216     si_ix=0;
217     for (;;)
218     {
219         const size_t si_name_ix = si->si_type+1; /* -1 is a valid index */
220         const char * const si_name = (si_name_ix >= sizeof(si_names)) ? "????" : si_names[si_name_ix];
221 	I32 ix;
222 	PerlIO_printf(Perl_debug_log, "STACK %"IVdf": %s\n",
223 						(IV)si_ix, si_name);
224 
225 	for (ix=0; ix<=si->si_cxix; ix++) {
226 
227 	    const PERL_CONTEXT * const cx = &(si->si_cxstack[ix]);
228 	    PerlIO_printf(Perl_debug_log,
229 		    "  CX %"IVdf": %-6s => ",
230 		    (IV)ix, PL_block_type[CxTYPE(cx)]
231 	    );
232 	    /* substitution contexts don't save stack pointers etc) */
233 	    if (CxTYPE(cx) == CXt_SUBST)
234 		PerlIO_printf(Perl_debug_log, "\n");
235 	    else {
236 
237 		/* Find the current context's stack range by searching
238 		 * forward for any higher contexts using this stack; failing
239 		 * that, it will be equal to the size of the stack for old
240 		 * stacks, or PL_stack_sp for the current stack
241 		 */
242 
243 		I32 i, stack_min, stack_max, mark_min, mark_max;
244 		const PERL_CONTEXT *cx_n = NULL;
245 		const PERL_SI *si_n;
246 
247 		/* there's a separate stack per SI, so only search
248 		 * this one */
249 
250 		for (i=ix+1; i<=si->si_cxix; i++) {
251 		    if (CxTYPE(cx) == CXt_SUBST)
252 			continue;
253 		    cx_n = &(si->si_cxstack[i]);
254 		    break;
255 		}
256 
257 		stack_min = cx->blk_oldsp;
258 
259 		if (cx_n) {
260 		    stack_max = cx_n->blk_oldsp;
261 		}
262 		else if (si == PL_curstackinfo) {
263 		    stack_max = PL_stack_sp - AvARRAY(si->si_stack);
264 		}
265 		else {
266 		    stack_max = AvFILLp(si->si_stack);
267 		}
268 
269 		/* for the other stack types, there's only one stack
270 		 * shared between all SIs */
271 
272 		si_n = si;
273 		i = ix;
274 		cx_n = NULL;
275 		for (;;) {
276 		    i++;
277 		    if (i > si_n->si_cxix) {
278 			if (si_n == PL_curstackinfo)
279 			    break;
280 			else {
281 			    si_n = si_n->si_next;
282 			    i = 0;
283 			}
284 		    }
285 		    if (CxTYPE(&(si_n->si_cxstack[i])) == CXt_SUBST)
286 			continue;
287 		    cx_n = &(si_n->si_cxstack[i]);
288 		    break;
289 		}
290 
291 		mark_min  = cx->blk_oldmarksp;
292 		if (cx_n) {
293 		    mark_max  = cx_n->blk_oldmarksp;
294 		}
295 		else {
296 		    mark_max = PL_markstack_ptr - PL_markstack;
297 		}
298 
299 		deb_stack_n(AvARRAY(si->si_stack),
300 			stack_min, stack_max, mark_min, mark_max);
301 
302 		if (CxTYPE(cx) == CXt_EVAL || CxTYPE(cx) == CXt_SUB
303 			|| CxTYPE(cx) == CXt_FORMAT)
304 		{
305 		    const OP * const retop = (CxTYPE(cx) == CXt_EVAL)
306 			    ? cx->blk_eval.retop : cx->blk_sub.retop;
307 
308 		    PerlIO_printf(Perl_debug_log, "  retop=%s\n",
309 			    retop ? OP_NAME(retop) : "(null)"
310 		    );
311 		}
312 	    }
313 	} /* next context */
314 
315 
316 	if (si == PL_curstackinfo)
317 	    break;
318 	si = si->si_next;
319 	si_ix++;
320 	if (!si)
321 	    break; /* shouldn't happen, but just in case.. */
322     } /* next stackinfo */
323 
324     PerlIO_printf(Perl_debug_log, "\n");
325 #else
326     PERL_UNUSED_CONTEXT;
327 #endif /* DEBUGGING */
328 }
329 
330 /*
331  * Local variables:
332  * c-indentation-style: bsd
333  * c-basic-offset: 4
334  * indent-tabs-mode: t
335  * End:
336  *
337  * ex: set ts=8 sts=4 sw=4 noet:
338  */
339