1 /****************************************************************************
2  *                                                                          *
3  *                            GNATMEM COMPONENTS                            *
4  *                                                                          *
5  *                                 G M E M                                  *
6  *                                                                          *
7  *                          C Implementation File                           *
8  *                                                                          *
9  *         Copyright (C) 2000-2003 Free Software Foundation, Inc.           *
10  *                                                                          *
11  * GNAT is free software;  you can  redistribute it  and/or modify it under *
12  * terms of the  GNU General Public License as published  by the Free Soft- *
13  * ware  Foundation;  either version 2,  or (at your option) any later ver- *
14  * sion.  GNAT is distributed in the hope that it will be useful, but WITH- *
15  * OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY *
16  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License *
17  * for  more details.  You should have  received  a copy of the GNU General *
18  * Public License  distributed with GNAT;  see file COPYING.  If not, write *
19  * to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, *
20  * MA 02111-1307, USA.                                                      *
21  *                                                                          *
22  * As a  special  exception,  if you  link  this file  with other  files to *
23  * produce an executable,  this file does not by itself cause the resulting *
24  * executable to be covered by the GNU General Public License. This except- *
25  * ion does not  however invalidate  any other reasons  why the  executable *
26  * file might be covered by the  GNU Public License.                        *
27  *                                                                          *
28  * GNAT was originally developed  by the GNAT team at  New York University. *
29  * Extensive contributions were provided by Ada Core Technologies Inc.      *
30  *                                                                          *
31  ****************************************************************************/
32 
33 /*  This unit reads the allocation tracking log produced by augmented
34     __gnat_malloc and __gnat_free procedures (see file a-raise.c) and
35     provides GNATMEM tool with gdb-compliant output. The output is
36     processed by GNATMEM to detect dynamic memory allocation errors.
37 
38     See GNATMEM section in GNAT User's Guide for more information.
39 
40     NOTE: This capability is currently supported on the following targets:
41 
42       DEC Unix
43       GNU/Linux x86
44       Solaris (sparc and x86) (*)
45       Windows 98/95/NT (x86)
46 
47     (*) on these targets, the compilation must be done with -funwind-tables to
48     be able to build the stack backtrace.
49 */
50 
51 #include <stdio.h>
52 
53 static FILE *gmemfile;
54 
55 /* tb_len is the number of call level supported by this module */
56 #define tb_len 200
57 static char * tracebk [tb_len];
58 static int cur_tb_len, cur_tb_pos;
59 
60 #define LOG_EOF   '*'
61 #define LOG_ALLOC 'A'
62 #define LOG_DEALL 'D'
63 
64 struct struct_storage_elmt {
65   char   Elmt;
66   void * Address;
67   size_t Size;
68 };
69 
70 extern void
71 convert_addresses (char *addrs[], int n_addr, void *buf, int *len);
72 
73 /* reads backtrace information from gmemfile placing them in tracebk
74    array. cur_tb_len is the size of this array
75 */
76 
77 static void
78 gmem_read_backtrace (void)
79 {
80   fread (&cur_tb_len, sizeof (int), 1, gmemfile);
81   fread (tracebk, sizeof (char *), cur_tb_len, gmemfile);
82   cur_tb_pos = 0;
83 }
84 
85 /* initialize gmem feature from the dumpname file. It returns 1 if the
86    dumpname has beed generated by GMEM (instrumented malloc/free) and 0 if not
87    (i.e. probably a GDB generated file).
88 */
89 
90 int __gnat_gmem_initialize (char *dumpname)
91 {
92   char header [10];
93 
94   gmemfile = fopen (dumpname, "rb");
95   fread (header, 10, 1, gmemfile);
96 
97   /* check for GMEM magic-tag */
98   if (memcmp (header, "GMEM DUMP\n", 10))
99     {
100       fclose (gmemfile);
101       return 0;
102     }
103 
104   return 1;
105 }
106 
107 /* initialize addr2line library */
108 
109 void __gnat_gmem_a2l_initialize (char *exename)
110 {
111   extern char **gnat_argv;
112   char s [100];
113   int l;
114 
115   gnat_argv [0] = exename;
116   convert_addresses (tracebk, 1, s, &l);
117 }
118 
119 /* Read next allocation of deallocation information from the GMEM file and
120    write an alloc/free information in buf to be processed by gnatmem */
121 
122 void
123 __gnat_gmem_read_next (struct struct_storage_elmt *buf)
124 {
125   void *addr;
126   size_t size;
127   int j;
128 
129   j = fgetc (gmemfile);
130   if (j == EOF)
131     {
132       fclose (gmemfile);
133       buf->Elmt = LOG_EOF;
134     }
135   else
136     {
137       switch (j)
138         {
139           case 'A' :
140             buf->Elmt = LOG_ALLOC;
141             fread (&(buf->Address), sizeof (void *), 1, gmemfile);
142             fread (&(buf->Size), sizeof (size_t), 1, gmemfile);
143             break;
144           case 'D' :
145             buf->Elmt = LOG_DEALL;
146             fread (&(buf->Address), sizeof (void *), 1, gmemfile);
147             break;
148           default:
149             puts ("GNATMEM dump file corrupt");
150             __gnat_os_exit (1);
151         }
152 
153       gmem_read_backtrace ();
154     }
155 }
156 
157 /* Read the next frame from the current traceback, and move the cursor to the
158    next frame */
159 
160 void __gnat_gmem_read_next_frame (void** addr)
161 {
162   if (cur_tb_pos >= cur_tb_len) {
163     *addr = NULL;
164   } else {
165     *addr = (void*)*(tracebk + cur_tb_pos);
166     ++cur_tb_pos;
167   }
168 }
169 
170 /* Converts addr into a symbolic traceback, and stores the result in buf
171    with a format suitable for gnatmem */
172 
173 void __gnat_gmem_symbolic (void * addr, char* buf, int* length)
174 {
175   char* addresses [] = { (char*)addr };
176   extern char** gnat_argv;
177 
178   convert_addresses (addresses, 1, buf, length);
179 }
180