1 
2 /*--------------------------------------------------------------------*/
3 /*--- DebugInfo.                              pub_tool_debuginfo.h ---*/
4 /*--------------------------------------------------------------------*/
5 
6 /*
7    This file is part of Valgrind, a dynamic binary instrumentation
8    framework.
9 
10    Copyright (C) 2000-2015 Julian Seward
11       jseward@acm.org
12 
13    This program is free software; you can redistribute it and/or
14    modify it under the terms of the GNU General Public License as
15    published by the Free Software Foundation; either version 2 of the
16    License, or (at your option) any later version.
17 
18    This program is distributed in the hope that it will be useful, but
19    WITHOUT ANY WARRANTY; without even the implied warranty of
20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21    General Public License for more details.
22 
23    You should have received a copy of the GNU General Public License
24    along with this program; if not, write to the Free Software
25    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26    02111-1307, USA.
27 
28    The GNU General Public License is contained in the file COPYING.
29 */
30 
31 #ifndef __PUB_TOOL_DEBUGINFO_H
32 #define __PUB_TOOL_DEBUGINFO_H
33 
34 #include "pub_tool_basics.h"   // VG_ macro
35 #include "pub_tool_xarray.h"   // XArray
36 
37 /*====================================================================*/
38 /*=== Obtaining debug information                                  ===*/
39 /*====================================================================*/
40 
41 /* Get the file/function/line number of the instruction at address
42    'a'.  For these four, if debug info for the address is found, it
43    copies the info into the buffer/UInt and returns True.  If not, it
44    returns False.  VG_(get_fnname) always
45    demangles C++ function names.  VG_(get_fnname_w_offset) is the
46    same, except it appends "+N" to symbol names to indicate offsets.  */
47 extern Bool VG_(get_filename) ( Addr a, const HChar** filename );
48 extern Bool VG_(get_fnname)   ( Addr a, const HChar** fnname );
49 extern Bool VG_(get_linenum)  ( Addr a, UInt* linenum );
50 extern Bool VG_(get_fnname_w_offset)
51                               ( Addr a, const HChar** fnname );
52 
53 /* This one is the most general.  It gives filename, line number and
54    optionally directory name.  filename and linenum may not be NULL.
55    dirname may be NULL, meaning that the caller does not want
56    directory name info.
57    If dirname is non-null, directory info is written to *dirname, if
58    it is available; if not available, '\0' is written to the first
59    byte.
60 
61    The character strings returned in *filename and *dirname are not
62    persistent. They will be freed when the DebugInfo they belong to
63    is discarded.
64 
65    Returned value indicates whether any filename/line info could be
66    found. */
67 extern Bool VG_(get_filename_linenum)
68                               ( Addr a,
69                                 /*OUT*/const HChar** filename,
70                                 /*OUT*/const HChar** dirname,
71                                 /*OUT*/UInt* linenum );
72 
73 /* Succeeds only if we find from debug info that 'a' is the address of the
74    first instruction in a function -- as opposed to VG_(get_fnname) which
75    succeeds if we find from debug info that 'a' is the address of any
76    instruction in a function.  Use this to instrument the start of
77    a particular function.  Nb: if an executable/shared object is stripped
78    of its symbols, this function will not be able to recognise function
79    entry points within it. */
80 extern Bool VG_(get_fnname_if_entry) ( Addr a, const HChar** fnname );
81 
82 typedef
83    enum {
84       Vg_FnNameNormal,        // A normal function.
85       Vg_FnNameMain,          // "main"
86       Vg_FnNameBelowMain      // Something below "main", eg. __libc_start_main.
87    } Vg_FnNameKind;           //   Such names are often filtered.
88 
89 /* Indicates what kind of fnname it is. */
90 extern Vg_FnNameKind VG_(get_fnname_kind) ( const HChar* name );
91 
92 /* Like VG_(get_fnname_kind), but takes a code address. */
93 extern Vg_FnNameKind VG_(get_fnname_kind_from_IP) ( Addr ip );
94 
95 /* Looks up data_addr in the collection of data symbols, and if found
96    puts its name (or as much as will fit) into dname[0 .. n_dname-1],
97    which is guaranteed to be zero terminated.  Also data_addr's offset
98    from the symbol start is put into *offset. */
99 extern Bool VG_(get_datasym_and_offset)( Addr data_addr,
100                                          /*OUT*/const HChar** dname,
101                                          /*OUT*/PtrdiffT* offset );
102 
103 /* Try to form some description of DATA_ADDR by looking at the DWARF3
104    debug info we have.  This considers all global variables, and 8
105    frames in the stacks of all threads.  Result is written at the ends
106    of DNAME{1,2}V, which are XArray*s of HChar, that have been
107    initialised by the caller, and True is returned.  If no description
108    is created, False is returned.  Regardless of the return value,
109    DNAME{1,2}V are guaranteed to be zero terminated after the call.
110 
111    Note that after the call, DNAME{1,2} may have more than one
112    trailing zero, so callers should establish the useful text length
113    using VG_(strlen) on the contents, rather than VG_(sizeXA) on the
114    XArray itself.
115 */
116 Bool VG_(get_data_description)(
117         /*MOD*/ XArray* /* of HChar */ dname1v,
118         /*MOD*/ XArray* /* of HChar */ dname2v,
119         Addr data_addr
120      );
121 
122 /* Succeeds if the address is within a shared object or the main executable.
123    It doesn't matter if debug info is present or not. */
124 extern Bool VG_(get_objname)  ( Addr a, const HChar** objname );
125 
126 
127 /* Cursor allowing to describe inlined function calls at an IP,
128    by doing successive calls to VG_(describe_IP). */
129 typedef  struct _InlIPCursor InlIPCursor;
130 
131 /* Returns info about the code address %eip:  the address, function
132    name (if known) and filename/line number (if known), like this:
133 
134       0x4001BF05: realloc (vg_replace_malloc.c:339)
135 
136    eip can possibly corresponds to inlined function call(s).
137    To describe eip and the inlined function calls, the following must
138    be done:
139        InlIPCursor *iipc = VG_(new_IIPC)(eip);
140        do {
141           buf = VG_(describe_IP)(eip, iipc);
142           ... use buf ...
143        } while (VG_(next_IIPC)(iipc));
144        VG_(delete_IIPC)(iipc);
145 
146    To only describe eip, without the inlined calls at eip, give a NULL iipc:
147        buf = VG_(describe_IP)(eip, NULL);
148 
149    Note, that the returned string is allocated in a static buffer local to
150    VG_(describe_IP). That buffer will be overwritten with every invocation.
151    Therefore, callers need to possibly stash away the string.
152 */
153 extern const HChar* VG_(describe_IP)(Addr eip, const InlIPCursor* iipc);
154 
155 /* Builds a IIPC (Inlined IP Cursor) to describe eip and all the inlined calls
156    at eip. Such a cursor must be deleted after use using VG_(delete_IIPC). */
157 extern InlIPCursor* VG_(new_IIPC)(Addr eip);
158 /* Move the cursor to the next call to describe.
159    Returns True if there are still calls to describe.
160    False if nothing to describe anymore. */
161 extern Bool VG_(next_IIPC)(InlIPCursor *iipc);
162 /* Free all memory associated with iipc. */
163 extern void VG_(delete_IIPC)(InlIPCursor *iipc);
164 
165 
166 
167 /* Get an XArray of StackBlock which describe the stack (auto) blocks
168    for this ip.  The caller is expected to free the XArray at some
169    point.  If 'arrays_only' is True, only array-typed blocks are
170    returned; otherwise blocks of all types are returned. */
171 
172 typedef
173    struct {
174       PtrdiffT base;       /* offset from sp or fp */
175       SizeT    szB;        /* size in bytes */
176       Bool     spRel;      /* True => sp-rel, False => fp-rel */
177       Bool     isVec;      /* does block have an array type, or not? */
178       HChar    name[16];   /* first 15 chars of name (asciiz) */
179    }
180    StackBlock;
181 
182 extern XArray* /* of StackBlock */
183 VG_(di_get_stack_blocks_at_ip)( Addr ip, Bool arrays_only );
184 
185 
186 /* Get an array of GlobalBlock which describe the global blocks owned
187    by the shared object characterised by the given di_handle.  Asserts
188    if the handle is invalid.  The caller is responsible for freeing
189    the array at some point.  If 'arrays_only' is True, only
190    array-typed blocks are returned; otherwise blocks of all types are
191    returned. */
192 
193 typedef
194    struct {
195       Addr  addr;
196       SizeT szB;
197       Bool  isVec;      /* does block have an array type, or not? */
198       HChar name[16];   /* first 15 chars of name (asciiz) */
199       HChar soname[16]; /* first 15 chars of name (asciiz) */
200    }
201    GlobalBlock;
202 
203 extern XArray* /* of GlobalBlock */
204 VG_(di_get_global_blocks_from_dihandle) ( ULong di_handle,
205                                           Bool  arrays_only );
206 
207 
208 /*====================================================================*/
209 /*=== Obtaining debug information                                  ===*/
210 /*====================================================================*/
211 
212 /* A way to make limited debuginfo queries on a per-mapped-object
213    basis. */
214 typedef  struct _DebugInfo  DebugInfo;
215 
216 /* Returns NULL if the DebugInfo isn't found.  It doesn't matter if
217    debug info is present or not. */
218 DebugInfo* VG_(find_DebugInfo) ( Addr a );
219 
220 /* Fish bits out of DebugInfos. */
221 Addr          VG_(DebugInfo_get_text_avma)   ( const DebugInfo *di );
222 SizeT         VG_(DebugInfo_get_text_size)   ( const DebugInfo *di );
223 Addr          VG_(DebugInfo_get_bss_avma)    ( const DebugInfo *di );
224 SizeT         VG_(DebugInfo_get_bss_size)    ( const DebugInfo *di );
225 Addr          VG_(DebugInfo_get_plt_avma)    ( const DebugInfo *di );
226 SizeT         VG_(DebugInfo_get_plt_size)    ( const DebugInfo *di );
227 Addr          VG_(DebugInfo_get_gotplt_avma) ( const DebugInfo *di );
228 SizeT         VG_(DebugInfo_get_gotplt_size) ( const DebugInfo *di );
229 Addr          VG_(DebugInfo_get_got_avma)    ( const DebugInfo *di );
230 SizeT         VG_(DebugInfo_get_got_size)    ( const DebugInfo *di );
231 const HChar*  VG_(DebugInfo_get_soname)      ( const DebugInfo *di );
232 const HChar*  VG_(DebugInfo_get_filename)    ( const DebugInfo *di );
233 PtrdiffT      VG_(DebugInfo_get_text_bias)   ( const DebugInfo *di );
234 
235 /* Function for traversing the DebugInfo list.  When called with NULL
236    it returns the first element; otherwise it returns the given
237    element's successor.  Note that the order of elements in the list
238    changes in response to most of the queries listed in this header,
239    that explicitly or implicitly have to search the list for a
240    particular code address.  So it isn't safe to assume that the order
241    of the list stays constant. */
242 const DebugInfo* VG_(next_DebugInfo)    ( const DebugInfo *di );
243 
244 /* A simple enumeration to describe the 'kind' of various kinds of
245    segments that arise from the mapping of object files. */
246 typedef
247    enum {
248       Vg_SectUnknown,
249       Vg_SectText,
250       Vg_SectData,
251       Vg_SectBSS,
252       Vg_SectGOT,
253       Vg_SectPLT,
254       Vg_SectGOTPLT,
255       Vg_SectOPD
256    }
257    VgSectKind;
258 
259 /* Convert a VgSectKind to a string, which must be copied if you want
260    to change it. */
261 const HChar* VG_(pp_SectKind)( VgSectKind kind );
262 
263 /* Given an address 'a', make a guess of which section of which object
264    it comes from.  If name is non-NULL, then the object's name is put
265    into *name. The returned name is persistent as long as the debuginfo
266    it belongs to isn't discarded. */
267 VgSectKind VG_(DebugInfo_sect_kind)( /*OUT*/const HChar** name, Addr a);
268 
269 
270 #endif   // __PUB_TOOL_DEBUGINFO_H
271 
272 /*--------------------------------------------------------------------*/
273 /*--- end                                                          ---*/
274 /*--------------------------------------------------------------------*/
275