xref: /dragonfly/contrib/gdb-7/gdb/probe.h (revision 335b9e93)
1 /* Generic SDT probe support for GDB.
2 
3    Copyright (C) 2012-2013 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 #if !defined (PROBE_H)
21 #define PROBE_H 1
22 
23 #include "gdb_vecs.h"
24 
25 /* Definition of a vector of probes.  */
26 
27 typedef struct probe *probe_p;
28 DEF_VEC_P (probe_p);
29 
30 struct linespec_result;
31 
32 /* Structure useful for passing the header names in the method
33    `gen_ui_out_table_header'.  */
34 
35 struct info_probe_column
36   {
37     /* The internal name of the field.  This string cannot be capitalized nor
38        localized, e.g., "extra_field".  */
39 
40     const char *field_name;
41 
42     /* The field name to be printed in the `info probes' command.  This
43        string can be capitalized and localized, e.g., _("Extra Field").  */
44     const char *print_name;
45   };
46 
47 typedef struct info_probe_column info_probe_column_s;
48 DEF_VEC_O (info_probe_column_s);
49 
50 /* Operations associated with a probe.  */
51 
52 struct probe_ops
53   {
54     /* Method responsible for verifying if LINESPECP is a valid linespec for
55        a probe breakpoint.  It should return 1 if it is, or zero if it is not.
56        It also should update LINESPECP in order to discard the breakpoint
57        option associated with this linespec.  For example, if the option is
58        `-probe', and the LINESPECP is `-probe abc', the function should
59        return 1 and set LINESPECP to `abc'.  */
60 
61     int (*is_linespec) (const char **linespecp);
62 
63     /* Function that should fill PROBES with known probes from OBJFILE.  */
64 
65     void (*get_probes) (VEC (probe_p) **probes, struct objfile *objfile);
66 
67     /* Function used to relocate addresses from PROBE according to some DELTA
68        provided.  */
69 
70     void (*relocate) (struct probe *probe, CORE_ADDR delta);
71 
72     /* Return the number of arguments of PROBE.  */
73 
74     unsigned (*get_probe_argument_count) (struct probe *probe);
75 
76     /* Evaluate the Nth argument from the PROBE, returning a value
77        corresponding to it.  The argument number is represented N.  */
78 
79     struct value *(*evaluate_probe_argument) (struct probe *probe,
80 					      unsigned n);
81 
82     /* Compile the Nth argument of the PROBE to an agent expression.
83        The argument number is represented by N.  */
84 
85     void (*compile_to_ax) (struct probe *probe, struct agent_expr *aexpr,
86 			   struct axs_value *axs_value, unsigned n);
87 
88     /* Set the semaphore associated with the PROBE.  This function only makes
89        sense if the probe has a concept of semaphore associated to a
90        probe.  */
91 
92     void (*set_semaphore) (struct probe *probe, struct gdbarch *gdbarch);
93 
94     /* Clear the semaphore associated with the PROBE.  This function only
95        makes sense if the probe has a concept of semaphore associated to
96        a probe.  */
97 
98     void (*clear_semaphore) (struct probe *probe, struct gdbarch *gdbarch);
99 
100     /* Function called to destroy PROBE's specific data.  This function
101        shall not free PROBE itself.  */
102 
103     void (*destroy) (struct probe *probe);
104 
105     /* Function responsible for providing the extra fields that will be
106        printed in the `info probes' command.  It should fill HEADS
107        with whatever extra fields it needs.  If the backend doesn't need
108        to print extra fields, it can set this method to NULL.  */
109 
110     void (*gen_info_probes_table_header) (VEC (info_probe_column_s) **heads);
111 
112     /* Function that will fill VALUES with the values of the extra fields
113        to be printed for PROBE.  If the backend implements the
114        `gen_ui_out_table_header' method, then it should implement
115        this method as well.  The backend should also guarantee that the
116        order and the number of values in the vector is exactly the same
117        as the order of the extra fields provided in the method
118        `gen_ui_out_table_header'.  If a certain field is to be skipped
119        when printing the information, you can push a NULL value in that
120        position in the vector.  */
121 
122     void (*gen_info_probes_table_values) (struct probe *probe,
123 					  VEC (const_char_ptr) **values);
124   };
125 
126 /* Definition of a vector of probe_ops.  */
127 
128 typedef const struct probe_ops *probe_ops_cp;
129 DEF_VEC_P (probe_ops_cp);
130 extern VEC (probe_ops_cp) *all_probe_ops;
131 
132 /* The probe_ops associated with the generic probe.  */
133 
134 extern const struct probe_ops probe_ops_any;
135 
136 /* Helper function that, given KEYWORDS, iterate over it trying to match
137    each keyword with LINESPECP.  If it succeeds, it updates the LINESPECP
138    pointer and returns 1.  Otherwise, nothing is done to LINESPECP and zero
139    is returned.  */
140 
141 extern int probe_is_linespec_by_keyword (const char **linespecp,
142 					 const char *const *keywords);
143 
144 /* Return specific PROBE_OPS * matching *LINESPECP and possibly updating
145    *LINESPECP to skip its "-probe-type " prefix.  Return &probe_ops_any if
146    *LINESPECP matches "-probe ", that is any unspecific probe.  Return NULL if
147    *LINESPECP is not identified as any known probe type, *LINESPECP is not
148    modified in such case.  */
149 
150 extern const struct probe_ops *probe_linespec_to_ops (const char **linespecp);
151 
152 /* The probe itself.  The struct contains generic information about the
153    probe, and then some specific information which should be stored in
154    the `probe_info' field.  */
155 
156 struct probe
157   {
158     /* The operations associated with this probe.  */
159     const struct probe_ops *pops;
160 
161     /* The objfile which contains this probe.  Even if the probe is also
162        present in a separate debug objfile, this variable always points to
163        the non-separate debug objfile.  */
164     struct objfile *objfile;
165 
166     /* The name of the probe.  */
167     const char *name;
168 
169     /* The provider of the probe.  It generally defaults to the name of
170        the objfile which contains the probe.  */
171     const char *provider;
172 
173     /* The address where the probe is inserted.  */
174     CORE_ADDR address;
175   };
176 
177 /* A helper for linespec that decodes a probe specification.  It returns a
178    symtabs_and_lines object and updates *ARGPTR or throws an error.  The
179    argument PTYPE specifies the type of the probe(s) to be parsed.  */
180 
181 extern struct symtabs_and_lines parse_probes (char **argptr,
182 					      struct linespec_result *canon);
183 
184 /* Helper function to register the proper probe_ops to a newly created probe.
185    This function is mainly called from `sym_get_probes'.  */
186 
187 extern void register_probe_ops (struct probe *probe);
188 
189 /* Given a PC, find an associated probe with type PTYPE.  If a probe is
190    found, return it.  If no probe is found, return NULL.  */
191 
192 extern struct probe *find_probe_by_pc (CORE_ADDR pc);
193 
194 /* Search OBJFILE for a probe with the given PROVIDER, NAME and PTYPE.
195    Return a VEC of all probes that were found.  If no matching probe
196    is found, return NULL.  The caller must free the VEC.  */
197 
198 extern VEC (probe_p) *find_probes_in_objfile (struct objfile *objfile,
199 					      const char *provider,
200 					      const char *name);
201 
202 /* Generate a `info probes' command output for probe_ops represented by
203    POPS.  If POPS is NULL it considers any probes types.  It is a helper
204    function that can be used by the probe backends to print their
205    `info probe TYPE'.  */
206 
207 extern void info_probes_for_ops (char *arg, int from_tty,
208 				 const struct probe_ops *pops);
209 
210 /* Return the `cmd_list_element' associated with the `info probes' command,
211    or create a new one if it doesn't exist.  Helper function that serves the
212    purpose of avoiding the case of a backend using the `cmd_list_element'
213    associated with `info probes', without having it registered yet.  */
214 
215 extern struct cmd_list_element **info_probes_cmdlist_get (void);
216 
217 /* A convenience function that finds a probe at the PC in FRAME and
218    evaluates argument N, with 0 <= N < number_of_args.  If there is no
219    probe at that location, or if the probe does not have enough arguments,
220    this returns NULL.  */
221 
222 extern struct value *probe_safe_evaluate_at_pc (struct frame_info *frame,
223 						unsigned n);
224 
225 #endif /* !defined (PROBE_H) */
226