pub_tool_execontext.h revision 9f207460d70d38c46c9e81996a3dcdf90961c6db 
1/*--------------------------------------------------------------------*/
2/*--- ExeContexts: long-lived stack traces.  pub_tool_execontext.h ---*/
3/*--------------------------------------------------------------------*/
4
5/*
6   This file is part of Valgrind, a dynamic binary instrumentation
7   framework.
8
9   Copyright (C) 2000-2009 Julian Seward
10      jseward@acm.org
11
12   This program is free software; you can redistribute it and/or
13   modify it under the terms of the GNU General Public License as
14   published by the Free Software Foundation; either version 2 of the
15   License, or (at your option) any later version.
16
17   This program is distributed in the hope that it will be useful, but
18   WITHOUT ANY WARRANTY; without even the implied warranty of
19   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20   General Public License for more details.
21
22   You should have received a copy of the GNU General Public License
23   along with this program; if not, write to the Free Software
24   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25   02111-1307, USA.
26
27   The GNU General Public License is contained in the file COPYING.
28*/
29
30#ifndef __PUB_TOOL_EXECONTEXT_H
31#define __PUB_TOOL_EXECONTEXT_H
32
33// It's an abstract type.
34typedef
35   struct _ExeContext
36   ExeContext;
37
38// Resolution type used to decide how closely to compare two errors for
39// equality.
40typedef
41   enum { Vg_LowRes, Vg_MedRes, Vg_HighRes }
42   VgRes;
43
44// Take a snapshot of the client's stack.  Search our collection of
45// ExeContexts to see if we already have it, and if not, allocate a
46// new one.  Either way, return a pointer to the context.  Context size
47// controlled by --num-callers option.
48//
49// This should only be used for long-lived stack traces.  If you want a
50// short-lived stack trace, use VG_(get_StackTrace)().
51//
52// If called from generated code, use VG_(get_running_tid)() to get the
53// current ThreadId.  If called from non-generated code, the current
54// ThreadId should be passed in by the core.  The initial IP value to
55// use is adjusted by first_ip_delta before the stack is unwound.
56// A safe value to pass is zero.
57//
58// See comments in pub_tool_stacktrace.h for precise definition of
59// the meaning of the code addresses in the returned ExeContext.
60extern
61ExeContext* VG_(record_ExeContext) ( ThreadId tid, Word first_ip_delta );
62
63// Trivial version of VG_(record_ExeContext), which just records the
64// thread's current program counter but does not do any stack
65// unwinding.  This is useful in some rare cases when we suspect the
66// stack might be outside mapped storage, and so unwinding
67// might cause a segfault.  In this case we can at least safely
68// produce a one-element stack trace, which is better than nothing.
69extern
70ExeContext* VG_(record_depth_1_ExeContext)( ThreadId tid );
71
72// Apply a function to every element in the ExeContext.  The parameter 'n'
73// gives the index of the passed ip.  Doesn't go below main() unless
74// --show-below-main=yes is set.
75extern void VG_(apply_ExeContext)( void(*action)(UInt n, Addr ip),
76                                   ExeContext* ec, UInt n_ips );
77
78// Compare two ExeContexts.  Number of callers considered depends on `res':
79//   Vg_LowRes:  2
80//   Vg_MedRes:  4
81//   Vg_HighRes: all
82extern Bool VG_(eq_ExeContext) ( VgRes res, ExeContext* e1, ExeContext* e2 );
83
84// Print an ExeContext.
85extern void VG_(pp_ExeContext) ( ExeContext* ec );
86
87// Get the 32-bit unique reference number for this ExeContext
88// (the "ExeContext Unique").  Guaranteed to be nonzero and to be a
89// multiple of four (iow, the lowest two bits are guaranteed to
90// be zero, so that callers can store other information there.
91extern UInt VG_(get_ECU_from_ExeContext)( ExeContext* e );
92
93// How many entries (frames) in this ExeContext?
94extern Int VG_(get_ExeContext_n_ips)( ExeContext* e );
95
96// Find the ExeContext that has the given ECU, if any.
97// NOTE: very slow.  Do not call often.
98extern ExeContext* VG_(get_ExeContext_from_ECU)( UInt uniq );
99
100// Make an ExeContext containing just 'a', and nothing else
101ExeContext* VG_(make_depth_1_ExeContext_from_Addr)( Addr a );
102
103// Is this a plausible-looking ECU ?  Catches some obvious stupid
104// cases, but does not guarantee that the ECU is really valid, that
105// is, has an associated ExeContext.
106static inline Bool VG_(is_plausible_ECU)( UInt ecu ) {
107   return (ecu > 0) && ((ecu & 3) == 0);
108}
109
110// Make an ExeContext containing exactly the specified stack frames.
111ExeContext* VG_(make_ExeContext_from_StackTrace)( Addr* ips, UInt n_ips );
112
113#endif   // __PUB_TOOL_EXECONTEXT_H
114
115/*--------------------------------------------------------------------*/
116/*--- end                                                          ---*/
117/*--------------------------------------------------------------------*/
118