1 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
2 // RUN:   -analyzer-checker=core \
3 // RUN:   -analyzer-checker=unix.cstring \
4 // RUN:   -analyzer-checker=unix.Malloc \
5 // RUN:   -analyzer-checker=alpha.unix.cstring \
6 // RUN:   -analyzer-checker=debug.ExprInspection \
7 // RUN:   -analyzer-config eagerly-assume=false
8 //
9 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference -DUSE_BUILTINS \
10 // RUN:   -analyzer-checker=core \
11 // RUN:   -analyzer-checker=unix.cstring \
12 // RUN:   -analyzer-checker=unix.Malloc \
13 // RUN:   -analyzer-checker=alpha.unix.cstring \
14 // RUN:   -analyzer-checker=debug.ExprInspection \
15 // RUN:   -analyzer-config eagerly-assume=false
16 //
17 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference -DVARIANT \
18 // RUN:   -analyzer-checker=core \
19 // RUN:   -analyzer-checker=unix.cstring \
20 // RUN:   -analyzer-checker=unix.Malloc \
21 // RUN:   -analyzer-checker=alpha.unix.cstring \
22 // RUN:   -analyzer-checker=debug.ExprInspection \
23 // RUN:   -analyzer-config eagerly-assume=false
24 //
25 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
26 // RUN:   -DUSE_BUILTINS -DVARIANT \
27 // RUN:   -analyzer-checker=core \
28 // RUN:   -analyzer-checker=alpha.security.taint \
29 // RUN:   -analyzer-checker=unix.cstring \
30 // RUN:   -analyzer-checker=unix.Malloc \
31 // RUN:   -analyzer-checker=alpha.unix.cstring \
32 // RUN:   -analyzer-checker=debug.ExprInspection \
33 // RUN:   -analyzer-config eagerly-assume=false
34 //
35 // RUN: %clang_analyze_cc1 -verify %s -Wno-null-dereference \
36 // RUN:   -DSUPPRESS_OUT_OF_BOUND \
37 // RUN:   -analyzer-checker=core \
38 // RUN:   -analyzer-checker=unix.cstring \
39 // RUN:   -analyzer-checker=unix.Malloc \
40 // RUN:   -analyzer-checker=alpha.unix.cstring.BufferOverlap \
41 // RUN:   -analyzer-checker=alpha.unix.cstring.NotNullTerminated \
42 // RUN:   -analyzer-checker=debug.ExprInspection \
43 // RUN:   -analyzer-config eagerly-assume=false
44 
45 //===----------------------------------------------------------------------===
46 // Declarations
47 //===----------------------------------------------------------------------===
48 
49 // Some functions are so similar to each other that they follow the same code
50 // path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is
51 // defined, make sure to use the variants instead to make sure they are still
52 // checked by the analyzer.
53 
54 // Some functions are implemented as builtins. These should be #defined as
55 // BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined.
56 
57 // Functions that have variants and are also available as builtins should be
58 // declared carefully! See memcpy() for an example.
59 
60 #ifdef USE_BUILTINS
61 # define BUILTIN(f) __builtin_ ## f
62 #else /* USE_BUILTINS */
63 # define BUILTIN(f) f
64 #endif /* USE_BUILTINS */
65 
66 #define NULL 0
67 typedef typeof(sizeof(int)) size_t;
68 
69 void clang_analyzer_eval(int);
70 
71 int scanf(const char *restrict format, ...);
72 void *malloc(size_t);
73 void free(void *);
74 
75 //===----------------------------------------------------------------------===
76 // strlen()
77 //===----------------------------------------------------------------------===
78 
79 #define strlen BUILTIN(strlen)
80 size_t strlen(const char *s);
81 
82 void strlen_constant0() {
83   clang_analyzer_eval(strlen("123") == 3); // expected-warning{{TRUE}}
84 }
85 
86 void strlen_constant1() {
87   const char *a = "123";
88   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
89 }
90 
91 void strlen_constant2(char x) {
92   char a[] = "123";
93   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
94 
95   a[0] = x;
96   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{UNKNOWN}}
97 }
98 
99 size_t strlen_null() {
100   return strlen(0); // expected-warning{{Null pointer passed as 1st argument to string length function}}
101 }
102 
103 size_t strlen_fn() {
104   return strlen((char*)&strlen_fn); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}}
105 }
106 
107 size_t strlen_nonloc() {
108 label:
109   return strlen((char*)&&label); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}}
110 }
111 
112 void strlen_subregion() {
113   struct two_strings { char a[2], b[2]; };
114   extern void use_two_strings(struct two_strings *);
115 
116   struct two_strings z;
117   use_two_strings(&z);
118 
119   size_t a = strlen(z.a);
120   z.b[0] = 5;
121   size_t b = strlen(z.a);
122   if (a == 0)
123     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
124 
125   use_two_strings(&z);
126 
127   size_t c = strlen(z.a);
128   if (a == 0)
129     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
130 }
131 
132 extern void use_string(char *);
133 void strlen_argument(char *x) {
134   size_t a = strlen(x);
135   size_t b = strlen(x);
136   if (a == 0)
137     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
138 
139   use_string(x);
140 
141   size_t c = strlen(x);
142   if (a == 0)
143     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
144 }
145 
146 extern char global_str[];
147 void strlen_global() {
148   size_t a = strlen(global_str);
149   size_t b = strlen(global_str);
150   if (a == 0) {
151     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
152     // Make sure clang_analyzer_eval does not invalidate globals.
153     clang_analyzer_eval(strlen(global_str) == 0); // expected-warning{{TRUE}}
154   }
155 
156   // Call a function with unknown effects, which should invalidate globals.
157   use_string(0);
158 
159   size_t c = strlen(global_str);
160   if (a == 0)
161     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
162 }
163 
164 void strlen_indirect(char *x) {
165   size_t a = strlen(x);
166   char *p = x;
167   char **p2 = &p;
168   size_t b = strlen(x);
169   if (a == 0)
170     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
171 
172   extern void use_string_ptr(char*const*);
173   use_string_ptr(p2);
174 
175   size_t c = strlen(x);
176   if (a == 0)
177     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
178 }
179 
180 void strlen_indirect2(char *x) {
181   size_t a = strlen(x);
182   char *p = x;
183   char **p2 = &p;
184   extern void use_string_ptr2(char**);
185   use_string_ptr2(p2);
186 
187   size_t c = strlen(x);
188   if (a == 0)
189     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
190 }
191 
192 void strlen_liveness(const char *x) {
193   if (strlen(x) < 5)
194     return;
195   clang_analyzer_eval(strlen(x) < 5); // expected-warning{{FALSE}}
196 }
197 
198 
199 size_t strlenWrapper(const char *str) {
200   return strlen(str);
201 }
202 
203 extern void invalidate(char *s);
204 
205 void testStrlenCallee() {
206   char str[42];
207   invalidate(str);
208   size_t lenBefore = strlenWrapper(str);
209   invalidate(str);
210   size_t lenAfter = strlenWrapper(str);
211   clang_analyzer_eval(lenBefore == lenAfter); // expected-warning{{UNKNOWN}}
212 }
213 
214 
215 //===----------------------------------------------------------------------===
216 // strnlen()
217 //===----------------------------------------------------------------------===
218 
219 size_t strnlen(const char *s, size_t maxlen);
220 
221 void strnlen_constant0() {
222   clang_analyzer_eval(strnlen("123", 10) == 3); // expected-warning{{TRUE}}
223 }
224 
225 void strnlen_constant1() {
226   const char *a = "123";
227   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
228 }
229 
230 void strnlen_constant2(char x) {
231   char a[] = "123";
232   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
233   a[0] = x;
234   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{UNKNOWN}}
235 }
236 
237 void strnlen_constant4() {
238   clang_analyzer_eval(strnlen("123456", 3) == 3); // expected-warning{{TRUE}}
239 }
240 
241 void strnlen_constant5() {
242   const char *a = "123456";
243   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
244 }
245 
246 void strnlen_constant6(char x) {
247   char a[] = "123456";
248   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
249   a[0] = x;
250   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{UNKNOWN}}
251 }
252 
253 size_t strnlen_null() {
254   return strnlen(0, 3); // expected-warning{{Null pointer passed as 1st argument to string length function}}
255 }
256 
257 size_t strnlen_fn() {
258   return strnlen((char*)&strlen_fn, 3); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}}
259 }
260 
261 size_t strnlen_nonloc() {
262 label:
263   return strnlen((char*)&&label, 3); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}}
264 }
265 
266 void strnlen_zero() {
267   clang_analyzer_eval(strnlen("abc", 0) == 0); // expected-warning{{TRUE}}
268   clang_analyzer_eval(strnlen(NULL, 0) == 0); // expected-warning{{TRUE}}
269 }
270 
271 size_t strnlen_compound_literal() {
272   // This used to crash because we don't model the string lengths of
273   // compound literals.
274   return strnlen((char[]) { 'a', 'b', 0 }, 1);
275 }
276 
277 size_t strnlen_unknown_limit(float f) {
278   // This used to crash because we don't model the integer values of floats.
279   return strnlen("abc", (int)f);
280 }
281 
282 void strnlen_is_not_strlen(char *x) {
283   clang_analyzer_eval(strnlen(x, 10) == strlen(x)); // expected-warning{{UNKNOWN}}
284 }
285 
286 void strnlen_at_limit(char *x) {
287   size_t len = strnlen(x, 10);
288   clang_analyzer_eval(len <= 10); // expected-warning{{TRUE}}
289   clang_analyzer_eval(len == 10); // expected-warning{{UNKNOWN}}
290   clang_analyzer_eval(len < 10); // expected-warning{{UNKNOWN}}
291 }
292 
293 void strnlen_at_actual(size_t limit) {
294   size_t len = strnlen("abc", limit);
295   clang_analyzer_eval(len <= 3); // expected-warning{{TRUE}}
296   // This is due to eager assertion in strnlen.
297   if (limit == 0) {
298     clang_analyzer_eval(len == 0); // expected-warning{{TRUE}}
299   } else {
300     clang_analyzer_eval(len == 3); // expected-warning{{UNKNOWN}}
301     clang_analyzer_eval(len < 3); // expected-warning{{UNKNOWN}}
302   }
303 }
304 
305 //===----------------------------------------------------------------------===
306 // strcpy()
307 //===----------------------------------------------------------------------===
308 
309 #ifdef VARIANT
310 
311 #define __strcpy_chk BUILTIN(__strcpy_chk)
312 char *__strcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
313 
314 #define strcpy(a,b) __strcpy_chk(a,b,(size_t)-1)
315 
316 #else /* VARIANT */
317 
318 #define strcpy BUILTIN(strcpy)
319 char *strcpy(char *restrict s1, const char *restrict s2);
320 
321 #endif /* VARIANT */
322 
323 
324 void strcpy_null_dst(char *x) {
325   strcpy(NULL, x); // expected-warning{{Null pointer passed as 1st argument to string copy function}}
326 }
327 
328 void strcpy_null_src(char *x) {
329   strcpy(x, NULL); // expected-warning{{Null pointer passed as 2nd argument to string copy function}}
330 }
331 
332 void strcpy_fn(char *x) {
333   strcpy(x, (char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
334 }
335 
336 void strcpy_fn_const(char *x) {
337   strcpy(x, (const char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
338 }
339 
340 extern int globalInt;
341 void strcpy_effects(char *x, char *y) {
342   char a = x[0];
343   if (globalInt != 42)
344     return;
345 
346   clang_analyzer_eval(strcpy(x, y) == x); // expected-warning{{TRUE}}
347   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
348   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
349   clang_analyzer_eval(globalInt == 42); // expected-warning{{TRUE}}
350 }
351 
352 #ifndef SUPPRESS_OUT_OF_BOUND
353 void strcpy_overflow(char *y) {
354   char x[4];
355   if (strlen(y) == 4)
356     strcpy(x, y); // expected-warning{{String copy function overflows the destination buffer}}
357 }
358 #endif
359 
360 void strcpy_no_overflow(char *y) {
361   char x[4];
362   if (strlen(y) == 3)
363     strcpy(x, y); // no-warning
364 }
365 
366 // PR37503
367 void *get_void_ptr();
368 char ***type_punned_ptr;
369 void strcpy_no_assertion(char c) {
370   *(unsigned char **)type_punned_ptr = (unsigned char *)(get_void_ptr());
371   strcpy(**type_punned_ptr, &c); // no-crash
372 }
373 
374 // PR49007
375 char f(char ***c, int *i) {
376   *(void **)c = i + 1;
377   return (**c)[0]; // no-crash
378 }
379 
380 //===----------------------------------------------------------------------===
381 // stpcpy()
382 //===----------------------------------------------------------------------===
383 
384 #ifdef VARIANT
385 
386 #define __stpcpy_chk BUILTIN(__stpcpy_chk)
387 char *__stpcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
388 
389 #define stpcpy(a,b) __stpcpy_chk(a,b,(size_t)-1)
390 
391 #else /* VARIANT */
392 
393 #define stpcpy BUILTIN(stpcpy)
394 char *stpcpy(char *restrict s1, const char *restrict s2);
395 
396 #endif /* VARIANT */
397 
398 
399 void stpcpy_effect(char *x, char *y) {
400   char a = x[0];
401 
402   clang_analyzer_eval(stpcpy(x, y) == &x[strlen(y)]); // expected-warning{{TRUE}}
403   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
404   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
405 }
406 
407 #ifndef SUPPRESS_OUT_OF_BOUND
408 void stpcpy_overflow(char *y) {
409   char x[4];
410   if (strlen(y) == 4)
411     stpcpy(x, y); // expected-warning{{String copy function overflows the destination buffer}}
412 }
413 #endif
414 
415 void stpcpy_no_overflow(char *y) {
416   char x[4];
417   if (strlen(y) == 3)
418     stpcpy(x, y); // no-warning
419 }
420 
421 //===----------------------------------------------------------------------===
422 // strcat()
423 //===----------------------------------------------------------------------===
424 
425 #ifdef VARIANT
426 
427 #define __strcat_chk BUILTIN(__strcat_chk)
428 char *__strcat_chk(char *restrict s1, const char *restrict s2, size_t destlen);
429 
430 #define strcat(a,b) __strcat_chk(a,b,(size_t)-1)
431 
432 #else /* VARIANT */
433 
434 #define strcat BUILTIN(strcat)
435 char *strcat(char *restrict s1, const char *restrict s2);
436 
437 #endif /* VARIANT */
438 
439 
440 void strcat_null_dst(char *x) {
441   strcat(NULL, x); // expected-warning{{Null pointer passed as 1st argument to string concatenation function}}
442 }
443 
444 void strcat_null_src(char *x) {
445   strcat(x, NULL); // expected-warning{{Null pointer passed as 2nd argument to string concatenation function}}
446 }
447 
448 void strcat_fn(char *x) {
449   strcat(x, (char*)&strcat_fn); // expected-warning{{Argument to string concatenation function is the address of the function 'strcat_fn', which is not a null-terminated string}}
450 }
451 
452 void strcat_effects(char *y) {
453   char x[8] = "123";
454   size_t orig_len = strlen(x);
455   char a = x[0];
456 
457   if (strlen(y) != 4)
458     return;
459 
460   clang_analyzer_eval(strcat(x, y) == x); // expected-warning{{TRUE}}
461   clang_analyzer_eval((int)strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
462 }
463 
464 #ifndef SUPPRESS_OUT_OF_BOUND
465 void strcat_overflow_0(char *y) {
466   char x[4] = "12";
467   if (strlen(y) == 4)
468     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
469 }
470 
471 void strcat_overflow_1(char *y) {
472   char x[4] = "12";
473   if (strlen(y) == 3)
474     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
475 }
476 
477 void strcat_overflow_2(char *y) {
478   char x[4] = "12";
479   if (strlen(y) == 2)
480     strcat(x, y); // expected-warning{{String concatenation function overflows the destination buffer}}
481 }
482 #endif
483 
484 void strcat_no_overflow(char *y) {
485   char x[5] = "12";
486   if (strlen(y) == 2)
487     strcat(x, y); // no-warning
488 }
489 
490 void strcat_symbolic_dst_length(char *dst) {
491 	strcat(dst, "1234");
492   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
493 }
494 
495 void strcat_symbolic_dst_length_taint(char *dst) {
496   scanf("%s", dst); // Taint data.
497   strcat(dst, "1234");
498   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
499 }
500 
501 void strcat_unknown_src_length(char *src, int offset) {
502 	char dst[8] = "1234";
503 	strcat(dst, &src[offset]);
504   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
505 }
506 
507 // There is no strcat_unknown_dst_length because if we can't get a symbolic
508 // length for the "before" strlen, we won't be able to set one for "after".
509 
510 void strcat_too_big(char *dst, char *src) {
511   // We assume this can never actually happen, so we don't get a warning.
512 	if (strlen(dst) != (((size_t)0) - 2))
513 		return;
514 	if (strlen(src) != 2)
515 		return;
516 	strcat(dst, src);
517 }
518 
519 
520 //===----------------------------------------------------------------------===
521 // strncpy()
522 //===----------------------------------------------------------------------===
523 
524 #ifdef VARIANT
525 
526 #define __strncpy_chk BUILTIN(__strncpy_chk)
527 char *__strncpy_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
528 
529 #define strncpy(a,b,n) __strncpy_chk(a,b,n,(size_t)-1)
530 
531 #else /* VARIANT */
532 
533 #define strncpy BUILTIN(strncpy)
534 char *strncpy(char *restrict s1, const char *restrict s2, size_t n);
535 
536 #endif /* VARIANT */
537 
538 
539 void strncpy_null_dst(char *x) {
540   strncpy(NULL, x, 5); // expected-warning{{Null pointer passed as 1st argument to string copy function}}
541 }
542 
543 void strncpy_null_src(char *x) {
544   strncpy(x, NULL, 5); // expected-warning{{Null pointer passed as 2nd argument to string copy function}}
545 }
546 
547 void strncpy_fn(char *x) {
548   strncpy(x, (char*)&strcpy_fn, 5); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
549 }
550 
551 void strncpy_effects(char *x, char *y) {
552   char a = x[0];
553 
554   clang_analyzer_eval(strncpy(x, y, 5) == x); // expected-warning{{TRUE}}
555   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{UNKNOWN}}
556   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
557 }
558 
559 #ifndef SUPPRESS_OUT_OF_BOUND
560 // Enabling the malloc checker enables some of the buffer-checking portions
561 // of the C-string checker.
562 void cstringchecker_bounds_nocrash() {
563   char *p = malloc(2);
564   strncpy(p, "AAA", sizeof("AAA"));
565   // expected-warning@-1 {{String copy function overflows the destination buffer}}
566   free(p);
567 }
568 
569 void strncpy_overflow(char *y) {
570   char x[4];
571   if (strlen(y) == 4)
572     strncpy(x, y, 5);
573     // expected-warning@-1 {{String copy function overflows the destination buffer}}
574 #ifndef VARIANT
575     // expected-warning@-3 {{size argument is too large; destination buffer has size 4, but size argument is 5}}
576 #endif
577 }
578 
579 void strncpy_no_overflow(char *y) {
580   char x[4];
581   if (strlen(y) == 3)
582     strncpy(x, y, 5);
583     // expected-warning@-1 {{String copy function overflows the destination buffer}}
584 #ifndef VARIANT
585     // expected-warning@-3 {{size argument is too large; destination buffer has size 4, but size argument is 5}}
586 #endif
587 }
588 
589 void strncpy_no_overflow2(char *y, int n) {
590 	if (n <= 4)
591 		return;
592 
593   char x[4];
594   if (strlen(y) == 3)
595     strncpy(x, y, n);
596   // expected-warning@-1 {{String copy function overflows the destination buffer}}
597 }
598 #endif
599 
600 void strncpy_truncate(char *y) {
601   char x[4];
602   if (strlen(y) == 4)
603     strncpy(x, y, 3); // no-warning
604 }
605 
606 void strncpy_no_truncate(char *y) {
607   char x[4];
608   if (strlen(y) == 3)
609     strncpy(x, y, 3); // no-warning
610 }
611 
612 void strncpy_exactly_matching_buffer(char *y) {
613 	char x[4];
614 	strncpy(x, y, 4); // no-warning
615 
616 	// strncpy does not null-terminate, so we have no idea what the strlen is
617 	// after this.
618   clang_analyzer_eval(strlen(x) > 4); // expected-warning{{UNKNOWN}}
619 }
620 
621 void strncpy_zero(char *src) {
622   char dst[] = "123";
623   strncpy(dst, src, 0); // no-warning
624 }
625 
626 void strncpy_empty() {
627   char dst[] = "123";
628   char src[] = "";
629   strncpy(dst, src, 4); // no-warning
630 }
631 
632 //===----------------------------------------------------------------------===
633 // strncat()
634 //===----------------------------------------------------------------------===
635 
636 #ifdef VARIANT
637 
638 #define __strncat_chk BUILTIN(__strncat_chk)
639 char *__strncat_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
640 
641 #define strncat(a,b,c) __strncat_chk(a,b,c, (size_t)-1)
642 
643 #else /* VARIANT */
644 
645 #define strncat BUILTIN(strncat)
646 char *strncat(char *restrict s1, const char *restrict s2, size_t n);
647 
648 #endif /* VARIANT */
649 
650 
651 void strncat_null_dst(char *x) {
652   strncat(NULL, x, 4); // expected-warning{{Null pointer passed as 1st argument to string concatenation function}}
653 }
654 
655 void strncat_null_src(char *x) {
656   strncat(x, NULL, 4); // expected-warning{{Null pointer passed as 2nd argument to string concatenation function}}
657 }
658 
659 void strncat_fn(char *x) {
660   strncat(x, (char*)&strncat_fn, 4); // expected-warning{{Argument to string concatenation function is the address of the function 'strncat_fn', which is not a null-terminated string}}
661 }
662 
663 void strncat_effects(char *y) {
664   char x[8] = "123";
665   size_t orig_len = strlen(x);
666   char a = x[0];
667 
668   if (strlen(y) != 4)
669     return;
670 
671   clang_analyzer_eval(strncat(x, y, strlen(y)) == x); // expected-warning{{TRUE}}
672   clang_analyzer_eval(strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
673 }
674 
675 #ifndef SUPPRESS_OUT_OF_BOUND
676 void strncat_overflow_0(char *y) {
677   char x[4] = "12";
678   if (strlen(y) == 4)
679     strncat(x, y, strlen(y));
680   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
681 }
682 
683 void strncat_overflow_1(char *y) {
684   char x[4] = "12";
685   if (strlen(y) == 3)
686     strncat(x, y, strlen(y));
687   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
688 }
689 
690 void strncat_overflow_2(char *y) {
691   char x[4] = "12";
692   if (strlen(y) == 2)
693     strncat(x, y, strlen(y));
694   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
695 }
696 
697 void strncat_overflow_3(char *y) {
698   char x[4] = "12";
699   if (strlen(y) == 4)
700     strncat(x, y, 2);
701   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
702 }
703 #endif
704 
705 void strncat_no_overflow_1(char *y) {
706   char x[5] = "12";
707   if (strlen(y) == 2)
708     strncat(x, y, strlen(y)); // no-warning
709 }
710 
711 void strncat_no_overflow_2(char *y) {
712   char x[4] = "12";
713   if (strlen(y) == 4)
714     strncat(x, y, 1); // no-warning
715 }
716 
717 void strncat_symbolic_dst_length(char *dst) {
718   strncat(dst, "1234", 5);
719   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
720 }
721 
722 #ifndef SUPPRESS_OUT_OF_BOUND
723 void strncat_symbolic_src_length(char *src) {
724   char dst[8] = "1234";
725   strncat(dst, src, 3);
726   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
727 
728   char dst2[8] = "1234";
729   strncat(dst2, src, 4);
730   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
731 }
732 
733 void strncat_unknown_src_length(char *src, int offset) {
734   char dst[8] = "1234";
735   strncat(dst, &src[offset], 3);
736   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
737 
738   char dst2[8] = "1234";
739   strncat(dst2, &src[offset], 4);
740   // expected-warning@-1 {{String concatenation function overflows the destination buffer}}
741 }
742 #endif
743 
744 // There is no strncat_unknown_dst_length because if we can't get a symbolic
745 // length for the "before" strlen, we won't be able to set one for "after".
746 
747 void strncat_symbolic_limit(unsigned limit) {
748   char dst[6] = "1234";
749   char src[] = "567";
750   strncat(dst, src, limit); // no-warning
751 
752   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
753   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
754 }
755 
756 void strncat_unknown_limit(float limit) {
757   char dst[6] = "1234";
758   char src[] = "567";
759   strncat(dst, src, (size_t)limit); // no-warning
760 
761   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
762   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
763 }
764 
765 void strncat_too_big(char *dst, char *src) {
766   // We assume this will never actually happen, so we don't get a warning.
767   if (strlen(dst) != (((size_t)0) - 2))
768     return;
769   if (strlen(src) != 2)
770     return;
771   strncat(dst, src, 2);
772 }
773 
774 void strncat_zero(char *src) {
775   char dst[] = "123";
776   strncat(dst, src, 0); // no-warning
777 }
778 
779 void strncat_empty() {
780   char dst[8] = "123";
781   char src[] = "";
782   strncat(dst, src, 4); // no-warning
783 }
784 
785 //===----------------------------------------------------------------------===
786 // strcmp()
787 //===----------------------------------------------------------------------===
788 
789 #define strcmp BUILTIN(strcmp)
790 int strcmp(const char * s1, const char * s2);
791 
792 void strcmp_check_modelling() {
793   char *x = "aa";
794   char *y = "a";
795   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
796   clang_analyzer_eval(strcmp(x, y) <= 0); // expected-warning{{FALSE}}
797   clang_analyzer_eval(strcmp(x, y) > 1); // expected-warning{{UNKNOWN}}
798 
799   clang_analyzer_eval(strcmp(y, x) < 0); // expected-warning{{TRUE}}
800   clang_analyzer_eval(strcmp(y, x) >= 0); // expected-warning{{FALSE}}
801   clang_analyzer_eval(strcmp(y, x) < -1); // expected-warning{{UNKNOWN}}
802 }
803 
804 void strcmp_constant0() {
805   clang_analyzer_eval(strcmp("123", "123") == 0); // expected-warning{{TRUE}}
806 }
807 
808 void strcmp_constant_and_var_0() {
809   char *x = "123";
810   clang_analyzer_eval(strcmp(x, "123") == 0); // expected-warning{{TRUE}}
811 }
812 
813 void strcmp_constant_and_var_1() {
814   char *x = "123";
815   clang_analyzer_eval(strcmp("123", x) == 0); // expected-warning{{TRUE}}
816 }
817 
818 void strcmp_0() {
819   char *x = "123";
820   char *y = "123";
821   clang_analyzer_eval(strcmp(x, y) == 0); // expected-warning{{TRUE}}
822 }
823 
824 void strcmp_1() {
825   char *x = "234";
826   char *y = "123";
827   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
828 }
829 
830 void strcmp_2() {
831   char *x = "123";
832   char *y = "234";
833   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
834 }
835 
836 void strcmp_null_0() {
837   char *x = NULL;
838   char *y = "123";
839   strcmp(x, y); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
840 }
841 
842 void strcmp_null_1() {
843   char *x = "123";
844   char *y = NULL;
845   strcmp(x, y); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
846 }
847 
848 void strcmp_diff_length_0() {
849   char *x = "12345";
850   char *y = "234";
851   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
852 }
853 
854 void strcmp_diff_length_1() {
855   char *x = "123";
856   char *y = "23456";
857   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
858 }
859 
860 void strcmp_diff_length_2() {
861   char *x = "12345";
862   char *y = "123";
863   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
864 }
865 
866 void strcmp_diff_length_3() {
867   char *x = "123";
868   char *y = "12345";
869   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
870 }
871 
872 void strcmp_embedded_null () {
873 	clang_analyzer_eval(strcmp("\0z", "\0y") == 0); // expected-warning{{TRUE}}
874 }
875 
876 void strcmp_unknown_arg (char *unknown) {
877 	clang_analyzer_eval(strcmp(unknown, unknown) == 0); // expected-warning{{TRUE}}
878 }
879 
880 union argument {
881    char *f;
882 };
883 
884 void function_pointer_cast_helper(char **a) {
885   strcmp("Hi", *a); // PR24951 crash
886 }
887 
888 void strcmp_union_function_pointer_cast(union argument a) {
889   void (*fPtr)(union argument *) = (void (*)(union argument *))function_pointer_cast_helper;
890 
891   fPtr(&a);
892 }
893 
894 int strcmp_null_argument(char *a) {
895   char *b = 0;
896   // Do not warn about the first argument!
897   return strcmp(a, b); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
898 }
899 
900 //===----------------------------------------------------------------------===
901 // strncmp()
902 //===----------------------------------------------------------------------===
903 
904 #define strncmp BUILTIN(strncmp)
905 int strncmp(const char *s1, const char *s2, size_t n);
906 
907 void strncmp_check_modelling() {
908   char *x = "aa";
909   char *y = "a";
910   clang_analyzer_eval(strncmp(x, y, 2) > 0); // expected-warning{{TRUE}}
911   clang_analyzer_eval(strncmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
912   clang_analyzer_eval(strncmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
913 
914   clang_analyzer_eval(strncmp(y, x, 2) < 0); // expected-warning{{TRUE}}
915   clang_analyzer_eval(strncmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
916   clang_analyzer_eval(strncmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
917 }
918 
919 void strncmp_constant0() {
920   clang_analyzer_eval(strncmp("123", "123", 3) == 0); // expected-warning{{TRUE}}
921 }
922 
923 void strncmp_constant_and_var_0() {
924   char *x = "123";
925   clang_analyzer_eval(strncmp(x, "123", 3) == 0); // expected-warning{{TRUE}}
926 }
927 
928 void strncmp_constant_and_var_1() {
929   char *x = "123";
930   clang_analyzer_eval(strncmp("123", x, 3) == 0); // expected-warning{{TRUE}}
931 }
932 
933 void strncmp_0() {
934   char *x = "123";
935   char *y = "123";
936   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
937 }
938 
939 void strncmp_1() {
940   char *x = "234";
941   char *y = "123";
942   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
943 }
944 
945 void strncmp_2() {
946   char *x = "123";
947   char *y = "234";
948   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
949 }
950 
951 void strncmp_null_0() {
952   char *x = NULL;
953   char *y = "123";
954   strncmp(x, y, 3); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
955 }
956 
957 void strncmp_null_1() {
958   char *x = "123";
959   char *y = NULL;
960   strncmp(x, y, 3); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
961 }
962 
963 void strncmp_diff_length_0() {
964   char *x = "12345";
965   char *y = "234";
966   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
967 }
968 
969 void strncmp_diff_length_1() {
970   char *x = "123";
971   char *y = "23456";
972   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
973 }
974 
975 void strncmp_diff_length_2() {
976   char *x = "12345";
977   char *y = "123";
978   clang_analyzer_eval(strncmp(x, y, 5) > 0); // expected-warning{{TRUE}}
979 }
980 
981 void strncmp_diff_length_3() {
982   char *x = "123";
983   char *y = "12345";
984   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
985 }
986 
987 void strncmp_diff_length_4() {
988   char *x = "123";
989   char *y = "12345";
990   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
991 }
992 
993 void strncmp_diff_length_5() {
994   char *x = "012";
995   char *y = "12345";
996   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
997 }
998 
999 void strncmp_diff_length_6() {
1000   char *x = "234";
1001   char *y = "12345";
1002   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1003 }
1004 
1005 void strncmp_embedded_null () {
1006 	clang_analyzer_eval(strncmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
1007 }
1008 
1009 int strncmp_null_argument(char *a, size_t n) {
1010   char *b = 0;
1011   // Do not warn about the first argument!
1012   return strncmp(a, b, n); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1013 }
1014 
1015 //===----------------------------------------------------------------------===
1016 // strcasecmp()
1017 //===----------------------------------------------------------------------===
1018 
1019 #define strcasecmp BUILTIN(strcasecmp)
1020 int strcasecmp(const char *s1, const char *s2);
1021 
1022 void strcasecmp_check_modelling() {
1023   char *x = "aa";
1024   char *y = "a";
1025   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1026   clang_analyzer_eval(strcasecmp(x, y) <= 0); // expected-warning{{FALSE}}
1027   clang_analyzer_eval(strcasecmp(x, y) > 1); // expected-warning{{UNKNOWN}}
1028 
1029   clang_analyzer_eval(strcasecmp(y, x) < 0); // expected-warning{{TRUE}}
1030   clang_analyzer_eval(strcasecmp(y, x) >= 0); // expected-warning{{FALSE}}
1031   clang_analyzer_eval(strcasecmp(y, x) < -1); // expected-warning{{UNKNOWN}}
1032 }
1033 
1034 void strcasecmp_constant0() {
1035   clang_analyzer_eval(strcasecmp("abc", "Abc") == 0); // expected-warning{{TRUE}}
1036 }
1037 
1038 void strcasecmp_constant_and_var_0() {
1039   char *x = "abc";
1040   clang_analyzer_eval(strcasecmp(x, "Abc") == 0); // expected-warning{{TRUE}}
1041 }
1042 
1043 void strcasecmp_constant_and_var_1() {
1044   char *x = "abc";
1045   clang_analyzer_eval(strcasecmp("Abc", x) == 0); // expected-warning{{TRUE}}
1046 }
1047 
1048 void strcasecmp_0() {
1049   char *x = "abc";
1050   char *y = "Abc";
1051   clang_analyzer_eval(strcasecmp(x, y) == 0); // expected-warning{{TRUE}}
1052 }
1053 
1054 void strcasecmp_1() {
1055   char *x = "Bcd";
1056   char *y = "abc";
1057   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1058 }
1059 
1060 void strcasecmp_2() {
1061   char *x = "abc";
1062   char *y = "Bcd";
1063   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1064 }
1065 
1066 void strcasecmp_null_0() {
1067   char *x = NULL;
1068   char *y = "123";
1069   strcasecmp(x, y); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
1070 }
1071 
1072 void strcasecmp_null_1() {
1073   char *x = "123";
1074   char *y = NULL;
1075   strcasecmp(x, y); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1076 }
1077 
1078 void strcasecmp_diff_length_0() {
1079   char *x = "abcde";
1080   char *y = "aBd";
1081   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1082 }
1083 
1084 void strcasecmp_diff_length_1() {
1085   char *x = "abc";
1086   char *y = "aBdef";
1087   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1088 }
1089 
1090 void strcasecmp_diff_length_2() {
1091   char *x = "aBcDe";
1092   char *y = "abc";
1093   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1094 }
1095 
1096 void strcasecmp_diff_length_3() {
1097   char *x = "aBc";
1098   char *y = "abcde";
1099   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1100 }
1101 
1102 void strcasecmp_embedded_null () {
1103 	clang_analyzer_eval(strcasecmp("ab\0zz", "ab\0yy") == 0); // expected-warning{{TRUE}}
1104 }
1105 
1106 int strcasecmp_null_argument(char *a) {
1107   char *b = 0;
1108   // Do not warn about the first argument!
1109   return strcasecmp(a, b); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1110 }
1111 
1112 //===----------------------------------------------------------------------===
1113 // strncasecmp()
1114 //===----------------------------------------------------------------------===
1115 
1116 #define strncasecmp BUILTIN(strncasecmp)
1117 int strncasecmp(const char *s1, const char *s2, size_t n);
1118 
1119 void strncasecmp_check_modelling() {
1120   char *x = "aa";
1121   char *y = "a";
1122   clang_analyzer_eval(strncasecmp(x, y, 2) > 0); // expected-warning{{TRUE}}
1123   clang_analyzer_eval(strncasecmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
1124   clang_analyzer_eval(strncasecmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
1125 
1126   clang_analyzer_eval(strncasecmp(y, x, 2) < 0); // expected-warning{{TRUE}}
1127   clang_analyzer_eval(strncasecmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
1128   clang_analyzer_eval(strncasecmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
1129 }
1130 
1131 void strncasecmp_constant0() {
1132   clang_analyzer_eval(strncasecmp("abc", "Abc", 3) == 0); // expected-warning{{TRUE}}
1133 }
1134 
1135 void strncasecmp_constant_and_var_0() {
1136   char *x = "abc";
1137   clang_analyzer_eval(strncasecmp(x, "Abc", 3) == 0); // expected-warning{{TRUE}}
1138 }
1139 
1140 void strncasecmp_constant_and_var_1() {
1141   char *x = "abc";
1142   clang_analyzer_eval(strncasecmp("Abc", x, 3) == 0); // expected-warning{{TRUE}}
1143 }
1144 
1145 void strncasecmp_0() {
1146   char *x = "abc";
1147   char *y = "Abc";
1148   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1149 }
1150 
1151 void strncasecmp_1() {
1152   char *x = "Bcd";
1153   char *y = "abc";
1154   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1155 }
1156 
1157 void strncasecmp_2() {
1158   char *x = "abc";
1159   char *y = "Bcd";
1160   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1161 }
1162 
1163 void strncasecmp_null_0() {
1164   char *x = NULL;
1165   char *y = "123";
1166   strncasecmp(x, y, 3); // expected-warning{{Null pointer passed as 1st argument to string comparison function}}
1167 }
1168 
1169 void strncasecmp_null_1() {
1170   char *x = "123";
1171   char *y = NULL;
1172   strncasecmp(x, y, 3); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1173 }
1174 
1175 void strncasecmp_diff_length_0() {
1176   char *x = "abcde";
1177   char *y = "aBd";
1178   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1179 }
1180 
1181 void strncasecmp_diff_length_1() {
1182   char *x = "abc";
1183   char *y = "aBdef";
1184   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1185 }
1186 
1187 void strncasecmp_diff_length_2() {
1188   char *x = "aBcDe";
1189   char *y = "abc";
1190   clang_analyzer_eval(strncasecmp(x, y, 5) > 0); // expected-warning{{TRUE}}
1191 }
1192 
1193 void strncasecmp_diff_length_3() {
1194   char *x = "aBc";
1195   char *y = "abcde";
1196   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1197 }
1198 
1199 void strncasecmp_diff_length_4() {
1200   char *x = "abcde";
1201   char *y = "aBc";
1202   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1203 }
1204 
1205 void strncasecmp_diff_length_5() {
1206   char *x = "abcde";
1207   char *y = "aBd";
1208   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1209 }
1210 
1211 void strncasecmp_diff_length_6() {
1212   char *x = "aBDe";
1213   char *y = "abc";
1214   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1215 }
1216 
1217 void strncasecmp_embedded_null () {
1218 	clang_analyzer_eval(strncasecmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
1219 }
1220 
1221 int strncasecmp_null_argument(char *a, size_t n) {
1222   char *b = 0;
1223   // Do not warn about the first argument!
1224   return strncasecmp(a, b, n); // expected-warning{{Null pointer passed as 2nd argument to string comparison function}}
1225 }
1226 
1227 //===----------------------------------------------------------------------===
1228 // strsep()
1229 //===----------------------------------------------------------------------===
1230 
1231 char *strsep(char **stringp, const char *delim);
1232 
1233 void strsep_null_delim(char *s) {
1234   strsep(&s, NULL); // expected-warning{{Null pointer passed as 2nd argument to strsep()}}
1235 }
1236 
1237 void strsep_null_search() {
1238   strsep(NULL, ""); // expected-warning{{Null pointer passed as 1st argument to strsep()}}
1239 }
1240 
1241 void strsep_return_original_pointer(char *s) {
1242   char *original = s;
1243   char *result = strsep(&s, ""); // no-warning
1244   clang_analyzer_eval(original == result); // expected-warning{{TRUE}}
1245 }
1246 
1247 void strsep_null_string() {
1248   char *s = NULL;
1249   char *result = strsep(&s, ""); // no-warning
1250   clang_analyzer_eval(result == NULL); // expected-warning{{TRUE}}
1251 }
1252 
1253 void strsep_changes_input_pointer(char *s) {
1254   char *original = s;
1255   strsep(&s, ""); // no-warning
1256   clang_analyzer_eval(s == original); // expected-warning{{UNKNOWN}}
1257   clang_analyzer_eval(s == NULL); // expected-warning{{UNKNOWN}}
1258 
1259   // Check that the value is symbolic.
1260   if (s == NULL) {
1261     clang_analyzer_eval(s == NULL); // expected-warning{{TRUE}}
1262   }
1263 }
1264 
1265 void strsep_changes_input_string() {
1266   char str[] = "abc";
1267 
1268   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{TRUE}}
1269 
1270   char *s = str;
1271   strsep(&s, "b"); // no-warning
1272 
1273   // The real strsep will change the first delimiter it finds into a NUL
1274   // character. For now, we just model the invalidation.
1275   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{UNKNOWN}}
1276 }
1277 
1278 //===----------------------------------------------------------------------===
1279 // memset() / explicit_bzero() / bzero()
1280 //===----------------------------------------------------------------------===
1281 
1282 void *memset(void *dest, int ch, size_t count);
1283 
1284 void bzero(void *dst, size_t count);
1285 void explicit_bzero(void *dest, size_t count);
1286 
1287 void *malloc(size_t size);
1288 void free(void *);
1289 
1290 void memset1_char_array_null() {
1291   char str[] = "abcd";
1292   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1293   memset(str, '\0', 2);
1294   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1295 }
1296 
1297 void memset2_char_array_null() {
1298   char str[] = "abcd";
1299   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1300   memset(str, '\0', strlen(str) + 1);
1301   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1302   clang_analyzer_eval(str[2] == 0);      // expected-warning{{TRUE}}
1303 }
1304 
1305 void memset3_char_malloc_null() {
1306   char *str = (char *)malloc(10 * sizeof(char));
1307   memset(str + 1, '\0', 8);
1308   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1309   free(str);
1310 }
1311 
1312 void memset4_char_malloc_null() {
1313   char *str = (char *)malloc(10 * sizeof(char));
1314   //void *str = malloc(10 * sizeof(char));
1315   memset(str, '\0', 10);
1316   clang_analyzer_eval(str[1] == 0);      // expected-warning{{TRUE}}
1317   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1318   free(str);
1319 }
1320 
1321 #ifdef SUPPRESS_OUT_OF_BOUND
1322 void memset5_char_malloc_overflow_null() {
1323   char *str = (char *)malloc(10 * sizeof(char));
1324   memset(str, '\0', 12);
1325   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1326   free(str);
1327 }
1328 #endif
1329 
1330 void memset6_char_array_nonnull() {
1331   char str[] = "abcd";
1332   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1333   memset(str, '0', 2);
1334   clang_analyzer_eval(str[0] == 'a');    // expected-warning{{UNKNOWN}}
1335   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{UNKNOWN}}
1336 }
1337 
1338 #ifdef SUPPRESS_OUT_OF_BOUND
1339 void memset8_char_array_nonnull() {
1340   char str[5] = "abcd";
1341   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1342   memset(str, '0', 10); // expected-warning{{'memset' will always overflow; destination buffer has size 5, but size argument is 10}}
1343   clang_analyzer_eval(str[0] != '0');     // expected-warning{{UNKNOWN}}
1344   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1345   clang_analyzer_eval(strlen(str) < 10);  // expected-warning{{FALSE}}
1346 }
1347 #endif
1348 
1349 struct POD_memset {
1350   int num;
1351   char c;
1352 };
1353 
1354 void memset10_struct() {
1355   struct POD_memset pod;
1356   char *str = (char *)&pod;
1357   pod.num = 1;
1358   pod.c = 1;
1359   clang_analyzer_eval(pod.num == 0); // expected-warning{{FALSE}}
1360   memset(str, 0, sizeof(struct POD_memset));
1361   clang_analyzer_eval(pod.num == 0); // expected-warning{{TRUE}}
1362 }
1363 
1364 #ifdef SUPPRESS_OUT_OF_BOUND
1365 void memset11_struct_field() {
1366   struct POD_memset pod;
1367   pod.num = 1;
1368   pod.c = '1';
1369   memset(&pod.num, 0, sizeof(struct POD_memset));
1370 
1371   clang_analyzer_eval(pod.num == 0);  // expected-warning{{TRUE}}
1372   clang_analyzer_eval(pod.c == '\0'); // expected-warning{{TRUE}}
1373 }
1374 
1375 void memset12_struct_field() {
1376   struct POD_memset pod;
1377   pod.num = 1;
1378   pod.c = '1';
1379   memset(&pod.c, 0, sizeof(struct POD_memset)); // expected-warning {{'memset' will always overflow; destination buffer has size 4, but size argument is 8}}
1380   clang_analyzer_eval(pod.num == 0); // expected-warning{{UNKNOWN}}
1381   clang_analyzer_eval(pod.c == 0);   // expected-warning{{UNKNOWN}}
1382 }
1383 
1384 union U_memset {
1385   int i;
1386   double d;
1387   char c;
1388 };
1389 
1390 void memset13_union_field() {
1391   union U_memset u;
1392   u.i = 5;
1393   memset(&u.i, '\0', sizeof(union U_memset));
1394   // Note: This should be TRUE, analyzer can't handle union perfectly now.
1395   clang_analyzer_eval(u.d == 0); // expected-warning{{UNKNOWN}}
1396 }
1397 #endif
1398 
1399 void memset14_region_cast() {
1400   char *str = (char *)malloc(10 * sizeof(int));
1401   int *array = (int *)str;
1402   memset(array, 0, 10 * sizeof(int));
1403   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{TRUE}}
1404   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1405   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1406   free(str);
1407 }
1408 
1409 void memset15_region_cast() {
1410   char *str = (char *)malloc(10 * sizeof(int));
1411   int *array = (int *)str;
1412   memset(array, 0, 5 * sizeof(int));
1413   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{UNKNOWN}}
1414   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1415   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1416   free(str);
1417 }
1418 
1419 int memset20_scalar() {
1420   int *x = malloc(sizeof(int));
1421   *x = 10;
1422   memset(x, 0, sizeof(int));
1423   int num = 1 / *x; // expected-warning{{Division by zero}}
1424   free(x);
1425   return num;
1426 }
1427 
1428 int memset21_scalar() {
1429   int *x = malloc(sizeof(int));
1430   memset(x, 0, 1);
1431   int num = 1 / *x;
1432   free(x);
1433   return num;
1434 }
1435 
1436 void memset22_array() {
1437   int array[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
1438   clang_analyzer_eval(array[1] == 2); // expected-warning{{TRUE}}
1439   memset(array, 0, sizeof(array));
1440   clang_analyzer_eval(array[1] == 0); // expected-warning{{TRUE}}
1441 }
1442 
1443 void memset23_array_pod_object() {
1444   struct POD_memset array[10];
1445   array[1].num = 10;
1446   array[1].c = 'c';
1447   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1448   memset(&array[1], 0, sizeof(struct POD_memset));
1449   clang_analyzer_eval(array[1].num == 0); // expected-warning{{UNKNOWN}}
1450 }
1451 
1452 void memset24_array_pod_object() {
1453   struct POD_memset array[10];
1454   array[1].num = 10;
1455   array[1].c = 'c';
1456   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1457   memset(array, 0, sizeof(array));
1458   clang_analyzer_eval(array[1].num == 0); // expected-warning{{TRUE}}
1459 }
1460 
1461 void memset25_symbol(char c) {
1462   char array[10] = {1};
1463   if (c != 0)
1464     return;
1465 
1466   memset(array, c, 10);
1467 
1468   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1469   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1470 }
1471 
1472 void memset26_upper_UCHAR_MAX() {
1473   char array[10] = {1};
1474 
1475   memset(array, 1024, 10);
1476 
1477   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1478   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1479 }
1480 
1481 void bzero1_null() {
1482   char *a = NULL;
1483 
1484   bzero(a, 10); // expected-warning{{Null pointer passed as 1st argument to memory clearance function}}
1485 }
1486 
1487 void bzero2_char_array_null() {
1488   char str[] = "abcd";
1489   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1490   bzero(str, 2);
1491   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1492 }
1493 
1494 void bzero3_char_ptr_null() {
1495   char *str = "abcd";
1496   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1497   bzero(str + 2, 2);
1498   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{FALSE}}
1499 }
1500 
1501 void explicit_bzero1_null() {
1502   char *a = NULL;
1503 
1504   explicit_bzero(a, 10); // expected-warning{{Null pointer passed as 1st argument to memory clearance function}}
1505 }
1506 
1507 void explicit_bzero2_clear_mypassword() {
1508   char passwd[7] = "passwd";
1509 
1510   explicit_bzero(passwd, sizeof(passwd)); // no-warning
1511 
1512   clang_analyzer_eval(strlen(passwd) == 0); // expected-warning{{TRUE}}
1513   clang_analyzer_eval(passwd[0] == '\0'); // expected-warning{{TRUE}}
1514 }
1515 
1516 void explicit_bzero3_out_ofbound() {
1517   char *privkey = (char *)malloc(7);
1518   const char newprivkey[10] = "mysafekey";
1519 
1520   strcpy(privkey, "random");
1521   explicit_bzero(privkey, sizeof(newprivkey));
1522 #ifndef SUPPRESS_OUT_OF_BOUND
1523   // expected-warning@-2 {{Memory clearance function overflows the destination buffer}}
1524 #endif
1525   clang_analyzer_eval(privkey[0] == '\0');
1526 #ifdef SUPPRESS_OUT_OF_BOUND
1527   // expected-warning@-2 {{UNKNOWN}}
1528 #endif
1529   free(privkey);
1530 }
1531 
1532 //===----------------------------------------------------------------------===
1533 // FIXMEs
1534 //===----------------------------------------------------------------------===
1535 
1536 // The analyzer_eval call below should evaluate to true. We are being too
1537 // aggressive in marking the (length of) src symbol dead. The length of dst
1538 // depends on src. This could be explicitly specified in the checker or the
1539 // logic for handling MetadataSymbol in SymbolManager needs to change.
1540 void strcat_symbolic_src_length(char *src) {
1541 	char dst[8] = "1234";
1542 	strcat(dst, src);
1543   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{UNKNOWN}}
1544 }
1545 
1546 
1547 // The analyzer_eval call below should evaluate to true. Most likely the same
1548 // issue as the test above.
1549 void strncpy_exactly_matching_buffer2(char *y) {
1550 	if (strlen(y) >= 4)
1551 		return;
1552 
1553 	char x[4];
1554 	strncpy(x, y, 4); // no-warning
1555 
1556 	// This time, we know that y fits in x anyway.
1557   clang_analyzer_eval(strlen(x) <= 3); // expected-warning{{UNKNOWN}}
1558 }
1559 
1560 void memset7_char_array_nonnull() {
1561   char str[5] = "abcd";
1562   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1563   memset(str, '0', 5);
1564   // FIXME: This should be TRUE.
1565   clang_analyzer_eval(str[0] == '0');    // expected-warning{{UNKNOWN}}
1566   clang_analyzer_eval(strlen(str) >= 5); // expected-warning{{TRUE}}
1567 }
1568 
1569 void memset16_region_cast() {
1570   char *str = (char *)malloc(10 * sizeof(int));
1571   int *array = (int *)str;
1572   memset(array, '0', 10 * sizeof(int));
1573   // FIXME: This should be TRUE.
1574   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1575   clang_analyzer_eval(strlen((char *)array) >= 10 * sizeof(int)); // expected-warning{{TRUE}}
1576   clang_analyzer_eval(strlen(str) >= 10 * sizeof(int));           // expected-warning{{TRUE}}
1577   free(str);
1578 }
1579 
1580 #ifdef SUPPRESS_OUT_OF_BOUND
1581 void memset17_region_cast() {
1582   char *str = (char *)malloc(10 * sizeof(int));
1583   int *array = (int *)str;
1584   memset(array, '0', 12 * sizeof(int));
1585   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1586   clang_analyzer_eval(strlen((char *)array) >= 12 * sizeof(int)); // expected-warning{{TRUE}}
1587   clang_analyzer_eval(strlen(str) >= 12 * sizeof(int));           // expected-warning{{TRUE}}
1588   free(str);
1589 }
1590 
1591 void memset18_memset_multiple_times() {
1592   char *str = (char *)malloc(10 * sizeof(char));
1593   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1594 
1595   memset(str + 2, '\0', 10 * sizeof(char));
1596   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1597   clang_analyzer_eval(str[1] == '\0');   // expected-warning{{UNKNOWN}}
1598 
1599   memset(str, '0', 10 * sizeof(char));
1600   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1601   // FIXME: This should be TRUE.
1602   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1603 
1604   free(str);
1605 }
1606 
1607 void memset19_memset_multiple_times() {
1608   char *str = (char *)malloc(10 * sizeof(char));
1609   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1610 
1611   memset(str, '0', 10 * sizeof(char));
1612   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1613   // FIXME: This should be TRUE.
1614   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1615 
1616   memset(str + 2, '\0', 10 * sizeof(char));
1617   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{UNKNOWN}}
1618   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1619 
1620   free(str);
1621 }
1622 #endif
1623 
1624 // The analyzer does not support binding a symbol with default binding.
1625 void memset27_symbol(char c) {
1626   char array[10] = {0};
1627   if (c < 10)
1628     return;
1629 
1630   memset(array, c, 10);
1631 
1632   clang_analyzer_eval(strlen(array) >= 10); // expected-warning{{TRUE}}
1633   // FIXME: This should be TRUE.
1634   clang_analyzer_eval(array[4] >= 10); // expected-warning{{UNKNOWN}}
1635 }
1636 
1637 void memset28() {
1638   short x;
1639   memset(&x, 1, sizeof(short));
1640   // This should be true.
1641   clang_analyzer_eval(x == 0x101); // expected-warning{{UNKNOWN}}
1642 }
1643 
1644 void memset29_plain_int_zero() {
1645   short x;
1646   memset(&x, 0, sizeof(short));
1647   clang_analyzer_eval(x == 0); // expected-warning{{TRUE}}
1648 }
1649 
1650 void test_memset_chk() {
1651   int x;
1652   __builtin___memset_chk(&x, 0, sizeof(x), __builtin_object_size(&x, 0));
1653   clang_analyzer_eval(x == 0); // expected-warning{{TRUE}}
1654 }
1655