1 /* libunwind - a platform-independent unwind library
2    Copyright (C) 2003-2004 Hewlett-Packard Co
3 	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4 
5 This file is part of libunwind.
6 
7 Permission is hereby granted, free of charge, to any person obtaining
8 a copy of this software and associated documentation files (the
9 "Software"), to deal in the Software without restriction, including
10 without limitation the rights to use, copy, modify, merge, publish,
11 distribute, sublicense, and/or sell copies of the Software, and to
12 permit persons to whom the Software is furnished to do so, subject to
13 the following conditions:
14 
15 The above copyright notice and this permission notice shall be
16 included in all copies or substantial portions of the Software.
17 
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
21 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
25 
26 #include <elf.h>
27 #include <fcntl.h>
28 #include <string.h>
29 #include <unistd.h>
30 
31 #include <sys/mman.h>
32 
33 #include "_UPT_internal.h"
34 
35 static int
get_unwind_info(struct elf_dyn_info * edi,pid_t pid,unw_addr_space_t as,unw_word_t ip,void * as_arg)36 get_unwind_info (struct elf_dyn_info *edi, pid_t pid, unw_addr_space_t as, unw_word_t ip, void *as_arg)
37 {
38   /* ANDROID support update. */
39   unsigned long segbase, mapoff;
40   struct elf_image ei;
41   int ret;
42   char *path = NULL;
43   /* End of ANDROID update. */
44 
45 #if UNW_TARGET_IA64 && defined(__linux)
46   if (!edi->ktab.start_ip && _Uia64_get_kernel_table (&edi->ktab) < 0)
47     return -UNW_ENOINFO;
48 
49   if (edi->ktab.format != -1 && ip >= edi->ktab.start_ip && ip < edi->ktab.end_ip)
50     return 0;
51 #endif
52 
53   if ((edi->di_cache.format != -1
54        && ip >= edi->di_cache.start_ip && ip < edi->di_cache.end_ip)
55 #if UNW_TARGET_ARM
56       || (edi->di_debug.format != -1
57        && ip >= edi->di_arm.start_ip && ip < edi->di_arm.end_ip)
58 #endif
59       || (edi->di_debug.format != -1
60        && ip >= edi->di_debug.start_ip && ip < edi->di_debug.end_ip))
61     return 0;
62 
63   invalidate_edi(edi);
64 
65   /* ANDROID support update. */
66   if (tdep_get_elf_image (as, &ei, pid, ip, &segbase, &mapoff, &path, as_arg) < 0)
67     return -UNW_ENOINFO;
68 
69   ret = tdep_find_unwind_table (edi, &ei, as, path, segbase, mapoff, ip);
70   free(path);
71   if (ret < 0)
72     return ret;
73   /* End of ANDROID update. */
74 
75   /* This can happen in corner cases where dynamically generated
76      code falls into the same page that contains the data-segment
77      and the page-offset of the code is within the first page of
78      the executable.  */
79   if (edi->di_cache.format != -1
80       && (ip < edi->di_cache.start_ip || ip >= edi->di_cache.end_ip))
81      edi->di_cache.format = -1;
82 
83   if (edi->di_debug.format != -1
84       && (ip < edi->di_debug.start_ip || ip >= edi->di_debug.end_ip))
85      edi->di_debug.format = -1;
86 
87   if (edi->di_cache.format == -1
88 #if UNW_TARGET_ARM
89       && edi->di_arm.format == -1
90 #endif
91       && edi->di_debug.format == -1)
92     return -UNW_ENOINFO;
93 
94   return 0;
95 }
96 
97 int
_UPT_find_proc_info(unw_addr_space_t as,unw_word_t ip,unw_proc_info_t * pi,int need_unwind_info,void * arg)98 _UPT_find_proc_info (unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi,
99 		     int need_unwind_info, void *arg)
100 {
101   struct UPT_info *ui = arg;
102   int ret = -UNW_ENOINFO;
103 
104   if (get_unwind_info (&ui->edi, ui->pid, as, ip, arg) < 0)
105     return -UNW_ENOINFO;
106 
107 #if UNW_TARGET_IA64
108   if (ui->edi.ktab.format != -1)
109     {
110       /* The kernel unwind table resides in local memory, so we have
111 	 to use the local address space to search it.  Since
112 	 _UPT_put_unwind_info() has no easy way of detecting this
113 	 case, we simply make a copy of the unwind-info, so
114 	 _UPT_put_unwind_info() can always free() the unwind-info
115 	 without ill effects.  */
116       ret = tdep_search_unwind_table (unw_local_addr_space, ip, &ui->edi.ktab, pi,
117 				      need_unwind_info, arg);
118       if (ret >= 0)
119 	{
120 	  if (!need_unwind_info)
121 	    pi->unwind_info = NULL;
122 	  else
123 	    {
124 	      void *mem = malloc (pi->unwind_info_size);
125 
126 	      if (!mem)
127 		return -UNW_ENOMEM;
128 	      memcpy (mem, pi->unwind_info, pi->unwind_info_size);
129 	      pi->unwind_info = mem;
130 	    }
131 	}
132     }
133 #endif
134 
135   if (ret == -UNW_ENOINFO && ui->edi.di_cache.format != -1)
136     ret = tdep_search_unwind_table (as, ip, &ui->edi.di_cache,
137 				    pi, need_unwind_info, arg);
138 
139 #if UNW_TARGET_ARM
140   if (ret == -UNW_ENOINFO && ui->edi.di_arm.format != -1)
141     ret = tdep_search_unwind_table (as, ip, &ui->edi.di_arm, pi,
142                                     need_unwind_info, arg);
143 #endif
144 
145   if (ret == -UNW_ENOINFO && ui->edi.di_debug.format != -1)
146     ret = tdep_search_unwind_table (as, ip, &ui->edi.di_debug, pi,
147 				    need_unwind_info, arg);
148 
149   return ret;
150 }
151