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/tmp/gdb-7.10/gdb/go-valprint.c
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1 /* Support for printing Go values for GDB, the GNU debugger.
2 
3  Copyright (C) 2012-2015 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  NOTE: This currently only provides special support for printing gccgo
21  strings. 6g objects are handled in Python.
22  The remaining gccgo types may also be handled in Python.
23  Strings are handled specially here, at least for now, in case the Python
24  support is unavailable. */
25 
26 #include "defs.h"
27 #include "gdbtypes.h"
28 #include "gdbcore.h"
29 #include "go-lang.h"
30 #include "c-lang.h"
31 #include "valprint.h"
32 
33 /* Print a Go string.
34 
35  Note: We assume
36  gdb_assert (go_classify_struct_type (type) == GO_TYPE_STRING). */
37 
38 static void
39 print_go_string (struct type *type, const gdb_byte *valaddr,
40  int embedded_offset, CORE_ADDR address,
41  struct ui_file *stream, int recurse,
42  const struct value *val,
43  const struct value_print_options *options)
44 {
45  struct gdbarch *gdbarch = get_type_arch (type);
46  struct type *elt_ptr_type = TYPE_FIELD_TYPE (type, 0);
47  struct type *elt_type = TYPE_TARGET_TYPE (elt_ptr_type);
49  /* TODO(dje): The encapsulation of what a pointer is belongs in value.c.
50  I.e. If there's going to be unpack_pointer, there should be
51  unpack_value_field_as_pointer. Do this until we can get
52  unpack_value_field_as_pointer. */
53  LONGEST addr;
54 
56 
57  if (! unpack_value_field_as_long (type, valaddr, embedded_offset, 0,
58  val, &addr))
59  error (_("Unable to read string address"));
60 
61  if (! unpack_value_field_as_long (type, valaddr, embedded_offset, 1,
62  val, &length))
63  error (_("Unable to read string length"));
64 
65  /* TODO(dje): Print address of struct or actual string? */
66  if (options->addressprint)
67  {
68  fputs_filtered (paddress (gdbarch, addr), stream);
69  fputs_filtered (" ", stream);
70  }
71 
72  if (length < 0)
73  {
74  fputs_filtered (_("<invalid length: "), stream);
75  fputs_filtered (plongest (addr), stream);
76  fputs_filtered (">", stream);
77  return;
78  }
79 
80  /* TODO(dje): Perhaps we should pass "UTF8" for ENCODING.
81  The target encoding is a global switch.
82  Either choice is problematic. */
83  val_print_string (elt_type, NULL, addr, length, stream, options);
84 }
85 
86 /* Implements the la_val_print routine for language Go. */
87 
88 void
89 go_val_print (struct type *type, const gdb_byte *valaddr, int embedded_offset,
90  CORE_ADDR address, struct ui_file *stream, int recurse,
91  const struct value *val,
92  const struct value_print_options *options)
93 {
94  CHECK_TYPEDEF (type);
95 
96  switch (TYPE_CODE (type))
97  {
98  case TYPE_CODE_STRUCT:
99  {
101 
102  switch (go_type)
103  {
104  case GO_TYPE_STRING:
105  if (! options->raw)
106  {
107  print_go_string (type, valaddr, embedded_offset, address,
108  stream, recurse, val, options);
109  return;
110  }
111  break;
112  default:
113  break;
114  }
115  }
116  /* Fall through. */
117 
118  default:
119  c_val_print (type, valaddr, embedded_offset, address, stream,
120  recurse, val, options);
121  break;
122  }
123 }
int unpack_value_field_as_long(struct type *type, const gdb_byte *valaddr, int embedded_offset, int fieldno, const struct value *val, LONGEST *result)
Definition: value.c:3242
bfd_vma CORE_ADDR
Definition: common-types.h:41
void c_val_print(struct type *, const gdb_byte *, int, CORE_ADDR, struct ui_file *, int, const struct value *, const struct value_print_options *)
Definition: c-valprint.c:134
#define _(String)
Definition: gdb_locale.h:40
#define TYPE_FIELD_TYPE(thistype, n)
Definition: gdbtypes.h:1368
const char * paddress(struct gdbarch *gdbarch, CORE_ADDR addr)
Definition: utils.c:2743
void fputs_filtered(const char *linebuffer, struct ui_file *stream)
Definition: utils.c:2145
Definition: gdbtypes.h:749
struct gdbarch * get_type_arch(const struct type *type)
Definition: gdbtypes.c:232
#define gdb_assert(expr)
Definition: gdb_assert.h:33
const gdb_byte * value_contents_for_printing_const(const struct value *value)
Definition: value.c:1181
enum go_type go_classify_struct_type(struct type *type)
Definition: go-lang.c:120
static void print_go_string(struct type *type, const gdb_byte *valaddr, int embedded_offset, CORE_ADDR address, struct ui_file *stream, int recurse, const struct value *val, const struct value_print_options *options)
Definition: go-valprint.c:39
Definition: value.c:172
bfd_byte gdb_byte
Definition: common-types.h:38
unsigned length
Definition: gdbtypes.h:807
go_type
Definition: go-lang.h:53
#define TYPE_TARGET_TYPE(thistype)
Definition: gdbtypes.h:1229
#define TYPE_CODE(thistype)
Definition: gdbtypes.h:1240
void go_val_print(struct type *type, const gdb_byte *valaddr, int embedded_offset, CORE_ADDR address, struct ui_file *stream, int recurse, const struct value *val, const struct value_print_options *options)
Definition: go-valprint.c:89
#define CHECK_TYPEDEF(TYPE)
Definition: gdbtypes.h:1817
int val_print_string(struct type *elttype, const char *encoding, CORE_ADDR addr, int len, struct ui_file *stream, const struct value_print_options *options)
Definition: valprint.c:2496
void error(const char *fmt,...)
Definition: errors.c:38
long long LONGEST
Definition: common-types.h:52