1 /****************************************************************************
2  * Copyright 2018-2019,2020 Thomas E. Dickey                                *
3  * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
4  *                                                                          *
5  * Permission is hereby granted, free of charge, to any person obtaining a  *
6  * copy of this software and associated documentation files (the            *
7  * "Software"), to deal in the Software without restriction, including      *
8  * without limitation the rights to use, copy, modify, merge, publish,      *
9  * distribute, distribute with modifications, sublicense, and/or sell       *
10  * copies of the Software, and to permit persons to whom the Software is    *
11  * furnished to do so, subject to the following conditions:                 *
12  *                                                                          *
13  * The above copyright notice and this permission notice shall be included  *
14  * in all copies or substantial portions of the Software.                   *
15  *                                                                          *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
25  * holders shall not be used in advertising or otherwise to promote the     *
26  * sale, use or other dealings in this Software without prior written       *
27  * authorization.                                                           *
28  ****************************************************************************/
29 
30 /****************************************************************************
31  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
32  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
33  *     and: Thomas E. Dickey                        1996-on                 *
34  *     and: Juergen Pfeifer                                                 *
35  ****************************************************************************/
36 
37 /*
38  *	lib_trace.c - Tracing/Debugging routines
39  *
40  * The _tracef() function is originally from pcurses (by Pavel Curtis) in 1982.
41  * pcurses allowed one to enable/disable tracing using traceon() and traceoff()
42  * functions.  ncurses provides a trace() function which allows one to
43  * selectively enable or disable several tracing features.
44  */
45 
46 #include <curses.priv.h>
47 #include <tic.h>
48 
49 #include <ctype.h>
50 
51 MODULE_ID("$Id: lib_trace.c,v 1.95 2020/02/02 23:34:34 tom Exp $")
52 
53 NCURSES_EXPORT_VAR(unsigned) _nc_tracing = 0; /* always define this */
54 
55 #ifdef TRACE
56 
57 #if USE_REENTRANT
58 NCURSES_EXPORT(const char *)
59 NCURSES_PUBLIC_VAR(_nc_tputs_trace) (void)
60 {
61     return CURRENT_SCREEN ? CURRENT_SCREEN->_tputs_trace : _nc_prescreen._tputs_trace;
62 }
63 NCURSES_EXPORT(long)
64 NCURSES_PUBLIC_VAR(_nc_outchars) (void)
65 {
66     return CURRENT_SCREEN ? CURRENT_SCREEN->_outchars : _nc_prescreen._outchars;
67 }
68 NCURSES_EXPORT(void)
69 _nc_set_tputs_trace(const char *s)
70 {
71     if (CURRENT_SCREEN)
72 	CURRENT_SCREEN->_tputs_trace = s;
73     else
74 	_nc_prescreen._tputs_trace = s;
75 }
76 NCURSES_EXPORT(void)
77 _nc_count_outchars(long increment)
78 {
79     if (CURRENT_SCREEN)
80 	CURRENT_SCREEN->_outchars += increment;
81     else
82 	_nc_prescreen._outchars += increment;
83 }
84 #else
85 NCURSES_EXPORT_VAR(const char *) _nc_tputs_trace = "";
86 NCURSES_EXPORT_VAR(long) _nc_outchars = 0;
87 #endif
88 
89 #define MyFP		_nc_globals.trace_fp
90 #define MyFD		_nc_globals.trace_fd
91 #define MyInit		_nc_globals.trace_opened
92 #define MyPath		_nc_globals.trace_fname
93 #define MyLevel		_nc_globals.trace_level
94 #define MyNested	_nc_globals.nested_tracef
95 #endif /* TRACE */
96 
97 NCURSES_EXPORT(unsigned)
98 curses_trace(unsigned tracelevel)
99 {
100     unsigned result;
101 #if defined(TRACE)
102     result = _nc_tracing;
103     if ((MyFP == 0) && tracelevel) {
104 	MyInit = TRUE;
105 	if (MyFD >= 0) {
106 	    MyFP = fdopen(MyFD, BIN_W);
107 	} else {
108 	    if (MyPath[0] == '\0') {
109 		size_t size = sizeof(MyPath) - 12;
110 		if (getcwd(MyPath, size) == 0) {
111 		    perror("curses: Can't get working directory");
112 		    exit(EXIT_FAILURE);
113 		}
114 		MyPath[size] = '\0';
115 		assert(strlen(MyPath) <= size);
116 		_nc_STRCAT(MyPath, "/trace", sizeof(MyPath));
117 		if (_nc_is_dir_path(MyPath)) {
118 		    _nc_STRCAT(MyPath, ".log", sizeof(MyPath));
119 		}
120 	    }
121 	    if (_nc_access(MyPath, W_OK) < 0
122 		|| (MyFD = open(MyPath, O_CREAT | O_EXCL | O_RDWR, 0600)) < 0
123 		|| (MyFP = fdopen(MyFD, BIN_W)) == 0) {
124 		;		/* EMPTY */
125 	    }
126 	}
127 	_nc_tracing = tracelevel;
128 	/* Try to set line-buffered mode, or (failing that) unbuffered,
129 	 * so that the trace-output gets flushed automatically at the
130 	 * end of each line.  This is useful in case the program dies.
131 	 */
132 	if (MyFP != 0) {
133 #if HAVE_SETVBUF		/* ANSI */
134 	    (void) setvbuf(MyFP, (char *) 0, _IOLBF, (size_t) 0);
135 #elif HAVE_SETBUF /* POSIX */
136 	    (void) setbuffer(MyFP, (char *) 0);
137 #endif
138 	}
139 	_tracef("TRACING NCURSES version %s.%d (tracelevel=%#x)",
140 		NCURSES_VERSION,
141 		NCURSES_VERSION_PATCH,
142 		tracelevel);
143     } else if (tracelevel == 0) {
144 	if (MyFP != 0) {
145 	    MyFD = dup(MyFD);	/* allow reopen of same file */
146 	    fclose(MyFP);
147 	    MyFP = 0;
148 	}
149 	_nc_tracing = tracelevel;
150     } else if (_nc_tracing != tracelevel) {
151 	_nc_tracing = tracelevel;
152 	_tracef("tracelevel=%#x", tracelevel);
153     }
154 #else
155     (void) tracelevel;
156     result = 0;
157 #endif
158     return result;
159 }
160 
161 #if defined(TRACE)
162 NCURSES_EXPORT(void)
163 trace(const unsigned int tracelevel)
164 {
165     curses_trace(tracelevel);
166 }
167 
168 static void
169 _nc_va_tracef(const char *fmt, va_list ap)
170 {
171     static const char Called[] = T_CALLED("");
172     static const char Return[] = T_RETURN("");
173 
174     bool before = FALSE;
175     bool after = FALSE;
176     unsigned doit = _nc_tracing;
177     int save_err = errno;
178     FILE *fp = MyFP;
179 
180 #ifdef TRACE
181     /* verbose-trace in the command-line utilities relies on this */
182     if (fp == 0 && !MyInit && _nc_tracing >= DEBUG_LEVEL(1))
183 	fp = stderr;
184 #endif
185 
186     if (strlen(fmt) >= sizeof(Called) - 1) {
187 	if (!strncmp(fmt, Called, sizeof(Called) - 1)) {
188 	    before = TRUE;
189 	    MyLevel++;
190 	} else if (!strncmp(fmt, Return, sizeof(Return) - 1)) {
191 	    after = TRUE;
192 	}
193 	if (before || after) {
194 	    if ((MyLevel <= 1)
195 		|| (doit & TRACE_ICALLS) != 0)
196 		doit &= (TRACE_CALLS | TRACE_CCALLS);
197 	    else
198 		doit = 0;
199 	}
200     }
201 
202     if (doit != 0 && fp != 0) {
203 #ifdef USE_PTHREADS
204 	/*
205 	 * TRACE_ICALLS is "really" needed to show normal use with threaded
206 	 * applications, since anything can be running during a napms(),
207 	 * making it appear in the hierarchical trace as it other functions
208 	 * are being called.
209 	 *
210 	 * Rather than add the complication of a per-thread stack, just
211 	 * show the thread-id in each line of the trace.
212 	 */
213 # if USE_WEAK_SYMBOLS
214 	if ((pthread_self))
215 # endif
216 #ifdef _WIN32
217 	    fprintf(fp, "%#lx:", (long) (intptr_t) pthread_self().p);
218 #else
219 	    fprintf(fp, "%#lx:", (long) (intptr_t) pthread_self());
220 #endif
221 #endif
222 	if (before || after) {
223 	    int n;
224 	    for (n = 1; n < MyLevel; n++)
225 		fputs("+ ", fp);
226 	}
227 	vfprintf(fp, fmt, ap);
228 	fputc('\n', fp);
229 	fflush(fp);
230     }
231 
232     if (after && MyLevel)
233 	MyLevel--;
234 
235     errno = save_err;
236 }
237 
238 NCURSES_EXPORT(void)
239 _tracef(const char *fmt, ...)
240 {
241     va_list ap;
242 
243     va_start(ap, fmt);
244     _nc_va_tracef(fmt, ap);
245     va_end(ap);
246 }
247 
248 /* Trace 'bool' return-values */
249 NCURSES_EXPORT(NCURSES_BOOL)
250 _nc_retrace_bool(int code)
251 {
252     T((T_RETURN("%s"), code ? "TRUE" : "FALSE"));
253     return code;
254 }
255 
256 /* Trace 'char' return-values */
257 NCURSES_EXPORT(char)
258 _nc_retrace_char(int code)
259 {
260     T((T_RETURN("%c"), code));
261     return (char) code;
262 }
263 
264 /* Trace 'int' return-values */
265 NCURSES_EXPORT(int)
266 _nc_retrace_int(int code)
267 {
268     T((T_RETURN("%d"), code));
269     return code;
270 }
271 
272 /* Trace 'unsigned' return-values */
273 NCURSES_EXPORT(unsigned)
274 _nc_retrace_unsigned(unsigned code)
275 {
276     T((T_RETURN("%#x"), code));
277     return code;
278 }
279 
280 /* Trace 'char*' return-values */
281 NCURSES_EXPORT(char *)
282 _nc_retrace_ptr(char *code)
283 {
284     T((T_RETURN("%s"), _nc_visbuf(code)));
285     return code;
286 }
287 
288 /* Trace 'const char*' return-values */
289 NCURSES_EXPORT(const char *)
290 _nc_retrace_cptr(const char *code)
291 {
292     T((T_RETURN("%s"), _nc_visbuf(code)));
293     return code;
294 }
295 
296 /* Trace 'NCURSES_CONST void*' return-values */
297 NCURSES_EXPORT(NCURSES_CONST void *)
298 _nc_retrace_cvoid_ptr(NCURSES_CONST void *code)
299 {
300     T((T_RETURN("%p"), code));
301     return code;
302 }
303 
304 /* Trace 'void*' return-values */
305 NCURSES_EXPORT(void *)
306 _nc_retrace_void_ptr(void *code)
307 {
308     T((T_RETURN("%p"), code));
309     return code;
310 }
311 
312 /* Trace 'SCREEN *' return-values */
313 NCURSES_EXPORT(SCREEN *)
314 _nc_retrace_sp(SCREEN *code)
315 {
316     T((T_RETURN("%p"), (void *) code));
317     return code;
318 }
319 
320 /* Trace 'WINDOW *' return-values */
321 NCURSES_EXPORT(WINDOW *)
322 _nc_retrace_win(WINDOW *code)
323 {
324     T((T_RETURN("%p"), (void *) code));
325     return code;
326 }
327 
328 NCURSES_EXPORT(char *)
329 _nc_fmt_funcptr(char *target, const char *source, size_t size)
330 {
331     size_t n;
332     char *dst = target;
333     bool leading = TRUE;
334 
335     union {
336 	int value;
337 	char bytes[sizeof(int)];
338     } byteorder;
339 
340     byteorder.value = 0x1234;
341 
342     *dst++ = '0';
343     *dst++ = 'x';
344 
345     for (n = 0; n < size; ++n) {
346 	unsigned ch = ((byteorder.bytes[0] == 0x34)
347 		       ? UChar(source[size - n - 1])
348 		       : UChar(source[n]));
349 	if (ch != 0 || (n + 1) >= size)
350 	    leading = FALSE;
351 	if (!leading) {
352 	    _nc_SPRINTF(dst, _nc_SLIMIT(TR_FUNC_LEN - (dst - target))
353 			"%02x", ch & 0xff);
354 	    dst += 2;
355 	}
356     }
357     *dst = '\0';
358     return target;
359 }
360 
361 #if USE_REENTRANT
362 /*
363  * Check if the given trace-mask is enabled.
364  *
365  * This function may be called from within one of the functions that fills
366  * in parameters for _tracef(), but in that case we do not want to lock the
367  * mutex, since it is already locked.
368  */
369 NCURSES_EXPORT(int)
370 _nc_use_tracef(unsigned mask)
371 {
372     bool result = FALSE;
373 
374     _nc_lock_global(tst_tracef);
375     if (!MyNested++) {
376 	if ((result = (_nc_tracing & (mask))) != 0
377 	    && _nc_try_global(tracef) == 0) {
378 	    /* we will call _nc_locked_tracef(), no nesting so far */
379 	} else {
380 	    /* we will not call _nc_locked_tracef() */
381 	    MyNested = 0;
382 	}
383     } else {
384 	/* we may call _nc_locked_tracef(), but with nested_tracef > 0 */
385 	result = (_nc_tracing & (mask));
386     }
387     _nc_unlock_global(tst_tracef);
388     return result;
389 }
390 
391 /*
392  * We call this if _nc_use_tracef() returns true, which means we must unlock
393  * the tracef mutex.
394  */
395 NCURSES_EXPORT(void)
396 _nc_locked_tracef(const char *fmt, ...)
397 {
398     va_list ap;
399 
400     va_start(ap, fmt);
401     _nc_va_tracef(fmt, ap);
402     va_end(ap);
403 
404     if (--(MyNested) == 0) {
405 	_nc_unlock_global(tracef);
406     }
407 }
408 #endif /* USE_REENTRANT */
409 
410 #endif /* TRACE */
411