xref: /petsc/src/sys/error/checkptr.c (revision e6e75211d226c622f451867f53ce5d558649ff4f)
1 #include <petsc/private/petscimpl.h>
2 #include <petscvalgrind.h>
3 
4 static PetscInt petsc_checkpointer_intensity = 1;
5 
6 #undef __FUNCT__
7 #define __FUNCT__ "PetscCheckPointerSetIntensity"
8 /*@
9    PetscCheckPointerSetIntensity - An intense pointer check registers a signal handler and attempts to dereference to
10    confirm whether the address is valid.  An intensity of 0 never uses signal handlers, 1 uses them when not in a "hot"
11    function, and intensity of 2 always uses a signal handler.
12 
13    Not Collective
14 
15    Input Arguments:
16 .  intensity - how much to check pointers for validity
17 
18    Level: advanced
19 
20 .seealso: PetscCheckPointer(), PetscFunctionBeginHot
21 @*/
22 PetscErrorCode PetscCheckPointerSetIntensity(PetscInt intensity)
23 {
24 
25   PetscFunctionBegin;
26   switch (intensity) {
27   case 0:
28   case 1:
29   case 2:
30     petsc_checkpointer_intensity = intensity;
31     break;
32   default: SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Intensity %D not in 0,1,2",intensity);
33   }
34   PetscFunctionReturn(0);
35 }
36 
37 /* ---------------------------------------------------------------------------------------*/
38 #if defined(PETSC_HAVE_SETJMP_H) && defined(PETSC_HAVE_SIGINFO_T)
39 #include <signal.h>
40 #include <setjmp.h>
41 PETSC_INTERN jmp_buf PetscSegvJumpBuf;
42 PETSC_INTERN void PetscSegv_sigaction(int, siginfo_t*, void *);
43 
44 /*@C
45      PetscCheckPointer - Returns PETSC_TRUE if a pointer points to accessible data
46 
47    Not Collective
48 
49    Input Parameters:
50 +     ptr - the pointer
51 -     dtype - the type of data the pointer is suppose to point to
52 
53    Level: developer
54 
55 @*/
56 PetscBool PetscCheckPointer(const void *ptr,PetscDataType dtype)
57 {
58   struct sigaction sa,oldsa;
59 
60   if (PETSC_RUNNING_ON_VALGRIND) return PETSC_TRUE;
61   if (!ptr) return PETSC_FALSE;
62   if (petsc_checkpointer_intensity < 1) return PETSC_TRUE;
63 
64   /* Skip the verbose check if we are inside a hot function. */
65   if (petscstack && petscstack->hotdepth > 0 && petsc_checkpointer_intensity < 2) return PETSC_TRUE;
66 
67   sigemptyset(&sa.sa_mask);
68   sa.sa_sigaction = PetscSegv_sigaction;
69   sa.sa_flags   = SA_SIGINFO;
70   sigaction(SIGSEGV, &sa, &oldsa);
71 
72   if (setjmp(PetscSegvJumpBuf)) {
73     /* A segv was triggered in the code below hence we return with an error code */
74     sigaction(SIGSEGV, &oldsa, NULL);/* reset old signal hanlder */
75     return PETSC_FALSE;
76   } else {
77     switch (dtype) {
78     case PETSC_INT:{
79       PETSC_UNUSED PetscInt x = (PetscInt)*(volatile PetscInt*)ptr;
80       break;
81     }
82 #if defined(PETSC_USE_COMPLEX)
83     case PETSC_SCALAR:{         /* C++ is seriously dysfunctional with volatile std::complex. */
84       PetscReal xreal = ((volatile PetscReal*)ptr)[0],ximag = ((volatile PetscReal*)ptr)[1];
85       PETSC_UNUSED volatile PetscScalar x = xreal + PETSC_i*ximag;
86       break;
87     }
88 #endif
89     case PETSC_REAL:{
90       PETSC_UNUSED PetscReal x = *(volatile PetscReal*)ptr;
91       break;
92     }
93     case PETSC_BOOL:{
94       PETSC_UNUSED PetscBool x = *(volatile PetscBool*)ptr;
95       break;
96     }
97     case PETSC_ENUM:{
98       PETSC_UNUSED PetscEnum x = *(volatile PetscEnum*)ptr;
99       break;
100     }
101     case PETSC_CHAR:{
102       PETSC_UNUSED char x = *(volatile char*)ptr;
103       break;
104     }
105     case PETSC_OBJECT:{
106       PETSC_UNUSED volatile PetscClassId classid = ((PetscObject)ptr)->classid;
107       break;
108     }
109     default:;
110     }
111   }
112   sigaction(SIGSEGV, &oldsa, NULL); /* reset old signal hanlder */
113   return PETSC_TRUE;
114 }
115 #else
116 PetscBool PetscCheckPointer(const void *ptr,PETSC_UNUSED PetscDataType dtype)
117 {
118   if (!ptr) return PETSC_FALSE;
119   return PETSC_TRUE;
120 }
121 #endif
122