xref: /petsc/src/sys/error/checkptr.c (revision a7631e779ee37285eb510131acb81bacea428671)
1 #include <petsc/private/petscimpl.h>
2 #include <petscvalgrind.h>
3 
4 static PetscInt petsc_checkpointer_intensity = 1;
5 
6 /*@
7    PetscCheckPointerSetIntensity - An intense pointer check registers a signal handler and attempts to dereference to
8    confirm whether the address is valid.  An intensity of 0 never uses signal handlers, 1 uses them when not in a "hot"
9    function, and intensity of 2 always uses a signal handler.
10 
11    Not Collective
12 
13    Input Arguments:
14 .  intensity - how much to check pointers for validity
15 
16    Level: advanced
17 
18 .seealso: PetscCheckPointer(), PetscFunctionBeginHot
19 @*/
20 PetscErrorCode PetscCheckPointerSetIntensity(PetscInt intensity)
21 {
22 
23   PetscFunctionBegin;
24   switch (intensity) {
25   case 0:
26   case 1:
27   case 2:
28     petsc_checkpointer_intensity = intensity;
29     break;
30   default: SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Intensity %D not in 0,1,2",intensity);
31   }
32   PetscFunctionReturn(0);
33 }
34 
35 /* ---------------------------------------------------------------------------------------*/
36 #if defined(PETSC_HAVE_SETJMP_H) && defined(PETSC_HAVE_SIGINFO_T)
37 #include <signal.h>
38 #include <setjmp.h>
39 PETSC_INTERN jmp_buf PetscSegvJumpBuf;
40 PETSC_INTERN void PetscSegv_sigaction(int, siginfo_t*, void *);
41 
42 /*@C
43      PetscCheckPointer - Returns PETSC_TRUE if a pointer points to accessible data
44 
45    Not Collective
46 
47    Input Parameters:
48 +     ptr - the pointer
49 -     dtype - the type of data the pointer is suppose to point to
50 
51    Level: developer
52 
53 @*/
54 PetscBool PetscCheckPointer(const void *ptr,PetscDataType dtype)
55 {
56   struct sigaction sa,oldsa;
57 
58   if (PETSC_RUNNING_ON_VALGRIND) return PETSC_TRUE;
59   if (!ptr) return PETSC_FALSE;
60   if (petsc_checkpointer_intensity < 1) return PETSC_TRUE;
61 
62   /* Skip the verbose check if we are inside a hot function. */
63   if (petscstack && petscstack->hotdepth > 0 && petsc_checkpointer_intensity < 2) return PETSC_TRUE;
64 
65   sigemptyset(&sa.sa_mask);
66   sa.sa_sigaction = PetscSegv_sigaction;
67   sa.sa_flags   = SA_SIGINFO;
68   sigaction(SIGSEGV, &sa, &oldsa);
69 
70   if (setjmp(PetscSegvJumpBuf)) {
71     /* A segv was triggered in the code below hence we return with an error code */
72     sigaction(SIGSEGV, &oldsa, NULL);/* reset old signal hanlder */
73     return PETSC_FALSE;
74   } else {
75     switch (dtype) {
76     case PETSC_INT:{
77       PETSC_UNUSED PetscInt x = (PetscInt)*(volatile PetscInt*)ptr;
78       break;
79     }
80 #if defined(PETSC_USE_COMPLEX)
81     case PETSC_SCALAR:{         /* C++ is seriously dysfunctional with volatile std::complex. */
82       PetscReal xreal = ((volatile PetscReal*)ptr)[0],ximag = ((volatile PetscReal*)ptr)[1];
83       PETSC_UNUSED volatile PetscScalar x = xreal + PETSC_i*ximag;
84       break;
85     }
86 #endif
87     case PETSC_REAL:{
88       PETSC_UNUSED PetscReal x = *(volatile PetscReal*)ptr;
89       break;
90     }
91     case PETSC_BOOL:{
92       PETSC_UNUSED PetscBool x = *(volatile PetscBool*)ptr;
93       break;
94     }
95     case PETSC_ENUM:{
96       PETSC_UNUSED PetscEnum x = *(volatile PetscEnum*)ptr;
97       break;
98     }
99     case PETSC_CHAR:{
100       PETSC_UNUSED char x = *(volatile char*)ptr;
101       break;
102     }
103     case PETSC_OBJECT:{
104       PETSC_UNUSED volatile PetscClassId classid = ((PetscObject)ptr)->classid;
105       break;
106     }
107     default:;
108     }
109   }
110   sigaction(SIGSEGV, &oldsa, NULL); /* reset old signal hanlder */
111   return PETSC_TRUE;
112 }
113 #else
114 PetscBool PetscCheckPointer(const void *ptr,PETSC_UNUSED PetscDataType dtype)
115 {
116   if (!ptr) return PETSC_FALSE;
117   return PETSC_TRUE;
118 }
119 #endif
120