xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/break-catch-exec.c (revision f8cf1a9151c7af1cb0bd8b09c13c66bca599c027)
1 /* Everything about exec catchpoints, for GDB.
2 
3    Copyright (C) 1986-2023 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #include "defs.h"
21 
22 #include "annotate.h"
23 #include "arch-utils.h"
24 #include "breakpoint.h"
25 #include "cli/cli-decode.h"
26 #include "inferior.h"
27 #include "mi/mi-common.h"
28 #include "target.h"
29 #include "valprint.h"
30 
31 /* Exec catchpoints.  */
32 
33 /* An instance of this type is used to represent an exec catchpoint.
34    A breakpoint is really of this type iff its ops pointer points to
35    CATCH_EXEC_BREAKPOINT_OPS.  */
36 
37 struct exec_catchpoint : public catchpoint
38 {
39   exec_catchpoint (struct gdbarch *gdbarch, bool temp, const char *cond_string)
40     : catchpoint (gdbarch, temp, cond_string)
41   {
42   }
43 
44   int insert_location (struct bp_location *) override;
45   int remove_location (struct bp_location *,
46 		       enum remove_bp_reason reason) override;
47   int breakpoint_hit (const struct bp_location *bl,
48 		      const address_space *aspace,
49 		      CORE_ADDR bp_addr,
50 		      const target_waitstatus &ws) override;
51   enum print_stop_action print_it (const bpstat *bs) const override;
52   bool print_one (bp_location **) const override;
53   void print_mention () const override;
54   void print_recreate (struct ui_file *fp) const override;
55 
56   /* Filename of a program whose exec triggered this catchpoint.
57      This field is only valid immediately after this catchpoint has
58      triggered.  */
59   gdb::unique_xmalloc_ptr<char> exec_pathname;
60 };
61 
62 int
63 exec_catchpoint::insert_location (struct bp_location *bl)
64 {
65   return target_insert_exec_catchpoint (inferior_ptid.pid ());
66 }
67 
68 int
69 exec_catchpoint::remove_location (struct bp_location *bl,
70 				  enum remove_bp_reason reason)
71 {
72   return target_remove_exec_catchpoint (inferior_ptid.pid ());
73 }
74 
75 int
76 exec_catchpoint::breakpoint_hit (const struct bp_location *bl,
77 				 const address_space *aspace,
78 				 CORE_ADDR bp_addr,
79 				 const target_waitstatus &ws)
80 {
81   if (ws.kind () != TARGET_WAITKIND_EXECD)
82     return 0;
83 
84   exec_pathname = make_unique_xstrdup (ws.execd_pathname ());
85   return 1;
86 }
87 
88 enum print_stop_action
89 exec_catchpoint::print_it (const bpstat *bs) const
90 {
91   struct ui_out *uiout = current_uiout;
92 
93   annotate_catchpoint (number);
94   maybe_print_thread_hit_breakpoint (uiout);
95   if (disposition == disp_del)
96     uiout->text ("Temporary catchpoint ");
97   else
98     uiout->text ("Catchpoint ");
99   if (uiout->is_mi_like_p ())
100     {
101       uiout->field_string ("reason", async_reason_lookup (EXEC_ASYNC_EXEC));
102       uiout->field_string ("disp", bpdisp_text (disposition));
103     }
104   uiout->field_signed ("bkptno", number);
105   uiout->text (" (exec'd ");
106   uiout->field_string ("new-exec", exec_pathname.get ());
107   uiout->text ("), ");
108 
109   return PRINT_SRC_AND_LOC;
110 }
111 
112 bool
113 exec_catchpoint::print_one (bp_location **last_loc) const
114 {
115   struct value_print_options opts;
116   struct ui_out *uiout = current_uiout;
117 
118   get_user_print_options (&opts);
119 
120   /* Field 4, the address, is omitted (which makes the columns
121      not line up too nicely with the headers, but the effect
122      is relatively readable).  */
123   if (opts.addressprint)
124     uiout->field_skip ("addr");
125   annotate_field (5);
126   uiout->text ("exec");
127   if (exec_pathname != NULL)
128     {
129       uiout->text (", program \"");
130       uiout->field_string ("what", exec_pathname.get ());
131       uiout->text ("\" ");
132     }
133 
134   if (uiout->is_mi_like_p ())
135     uiout->field_string ("catch-type", "exec");
136 
137   return true;
138 }
139 
140 void
141 exec_catchpoint::print_mention () const
142 {
143   gdb_printf (_("Catchpoint %d (exec)"), number);
144 }
145 
146 /* Implement the "print_recreate" method for exec catchpoints.  */
147 
148 void
149 exec_catchpoint::print_recreate (struct ui_file *fp) const
150 {
151   gdb_printf (fp, "catch exec");
152   print_recreate_thread (fp);
153 }
154 
155 /* This function attempts to parse an optional "if <cond>" clause
156    from the arg string.  If one is not found, it returns NULL.
157 
158    Else, it returns a pointer to the condition string.  (It does not
159    attempt to evaluate the string against a particular block.)  And,
160    it updates arg to point to the first character following the parsed
161    if clause in the arg string.  */
162 
163 const char *
164 ep_parse_optional_if_clause (const char **arg)
165 {
166   const char *cond_string;
167 
168   if (((*arg)[0] != 'i') || ((*arg)[1] != 'f') || !isspace ((*arg)[2]))
169     return NULL;
170 
171   /* Skip the "if" keyword.  */
172   (*arg) += 2;
173 
174   /* Skip any extra leading whitespace, and record the start of the
175      condition string.  */
176   *arg = skip_spaces (*arg);
177   cond_string = *arg;
178 
179   /* Assume that the condition occupies the remainder of the arg
180      string.  */
181   (*arg) += strlen (cond_string);
182 
183   return cond_string;
184 }
185 
186 /* Commands to deal with catching events, such as signals, exceptions,
187    process start/exit, etc.  */
188 
189 static void
190 catch_exec_command_1 (const char *arg, int from_tty,
191 		      struct cmd_list_element *command)
192 {
193   struct gdbarch *gdbarch = get_current_arch ();
194   const char *cond_string = NULL;
195   bool temp = command->context () == CATCH_TEMPORARY;
196 
197   if (!arg)
198     arg = "";
199   arg = skip_spaces (arg);
200 
201   /* The allowed syntax is:
202      catch exec
203      catch exec if <cond>
204 
205      First, check if there's an if clause.  */
206   cond_string = ep_parse_optional_if_clause (&arg);
207 
208   if ((*arg != '\0') && !isspace (*arg))
209     error (_("Junk at end of arguments."));
210 
211   std::unique_ptr<exec_catchpoint> c
212     (new exec_catchpoint (gdbarch, temp, cond_string));
213 
214   install_breakpoint (0, std::move (c), 1);
215 }
216 
217 void _initialize_break_catch_exec ();
218 void
219 _initialize_break_catch_exec ()
220 {
221   add_catch_command ("exec", _("Catch calls to exec."),
222 		     catch_exec_command_1,
223 		     NULL,
224 		     CATCH_PERMANENT,
225 		     CATCH_TEMPORARY);
226 }
227