binutils-gdb/gdb/location.h
Andrew Burgess b6e05abee3 gdb: update the comment on string_to_event_location
The comment on string_to_event_location is (I believe) out of date.
This commit fixes the two issues I see:

  1. This function can't return NULL any more.  The implementation
  calls string_to_explicit_location which can return NULL, but if this
  is the case we then call string_to_event_location_basic, which I
  don't believe can ever return NULL.

  2. I've removed the mention that the returned string is malloc'd,
  though this is true, now that we return a managed pointer, I believe
  the source of the memory allocation is irrelevant, and so, shouldn't
  be discussed in the header comment.

There should be no user visible changes after this commit.
2022-02-02 16:27:36 +00:00

284 lines
8.9 KiB
C++

/* Data structures and API for event locations in GDB.
Copyright (C) 2013-2022 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef LOCATION_H
#define LOCATION_H
#include "symtab.h"
struct language_defn;
struct event_location;
/* An enumeration of possible signs for a line offset. */
enum offset_relative_sign
{
/* No sign */
LINE_OFFSET_NONE,
/* A plus sign ("+") */
LINE_OFFSET_PLUS,
/* A minus sign ("-") */
LINE_OFFSET_MINUS,
/* A special "sign" for unspecified offset. */
LINE_OFFSET_UNKNOWN
};
/* A line offset in a location. */
struct line_offset
{
/* Line offset and any specified sign. */
int offset;
enum offset_relative_sign sign;
};
/* An enumeration of the various ways to specify a stop event
location (used with create_breakpoint). */
enum event_location_type
{
/* A traditional linespec. */
LINESPEC_LOCATION,
/* An address in the inferior. */
ADDRESS_LOCATION,
/* An explicit location. */
EXPLICIT_LOCATION,
/* A probe location. */
PROBE_LOCATION
};
/* A traditional linespec. */
struct linespec_location
{
/* Whether the function name is fully-qualified or not. */
symbol_name_match_type match_type;
/* The linespec. */
char *spec_string;
};
/* An explicit location. This structure is used to bypass the
parsing done on linespecs. It still has the same requirements
as linespecs, though. For example, source_filename requires
at least one other field. */
struct explicit_location
{
/* The source filename. Malloc'd. */
char *source_filename;
/* The function name. Malloc'd. */
char *function_name;
/* Whether the function name is fully-qualified or not. */
symbol_name_match_type func_name_match_type;
/* The name of a label. Malloc'd. */
char *label_name;
/* A line offset relative to the start of the symbol
identified by the above fields or the current symtab
if the other fields are NULL. */
struct line_offset line_offset;
};
/* Return the type of the given event location. */
extern enum event_location_type
event_location_type (const struct event_location *);
/* Return a linespec string representation of the given explicit
location. The location must already be canonicalized/valid. */
extern std::string
explicit_location_to_linespec (const struct explicit_location *explicit_loc);
/* Return a string representation of the LOCATION.
This function may return NULL for unspecified linespecs,
e.g, LINESPEC_LOCATION and spec_string is NULL.
The result is cached in LOCATION. */
extern const char *
event_location_to_string (struct event_location *location);
/* A deleter for a struct event_location. */
struct event_location_deleter
{
void operator() (event_location *location) const;
};
/* A unique pointer for event_location. */
typedef std::unique_ptr<event_location, event_location_deleter>
event_location_up;
/* Create a new linespec location. */
extern event_location_up new_linespec_location
(const char **linespec, symbol_name_match_type match_type);
/* Return the linespec location of the given event_location (which
must be of type LINESPEC_LOCATION). */
extern const linespec_location *
get_linespec_location (const struct event_location *location);
/* Create a new address location.
ADDR is the address corresponding to this event_location.
ADDR_STRING, a string of ADDR_STRING_LEN characters, is
the expression that was parsed to determine the address ADDR. */
extern event_location_up new_address_location (CORE_ADDR addr,
const char *addr_string,
int addr_string_len);
/* Return the address location (a CORE_ADDR) of the given event_location
(which must be of type ADDRESS_LOCATION). */
extern CORE_ADDR
get_address_location (const struct event_location *location);
/* Return the expression (a string) that was used to compute the address
of the given event_location (which must be of type ADDRESS_LOCATION). */
extern const char *
get_address_string_location (const struct event_location *location);
/* Create a new probe location. */
extern event_location_up new_probe_location (std::string &&probe);
/* Return the probe location (a string) of the given event_location
(which must be of type PROBE_LOCATION). */
extern const char *
get_probe_location (const struct event_location *location);
/* Initialize the given explicit location. */
extern void
initialize_explicit_location (struct explicit_location *explicit_loc);
/* Create a new explicit location. If not NULL, EXPLICIT is checked for
validity. If invalid, an exception is thrown. */
extern event_location_up
new_explicit_location (const struct explicit_location *explicit_loc);
/* Return the explicit location of the given event_location
(which must be of type EXPLICIT_LOCATION). */
extern struct explicit_location *
get_explicit_location (struct event_location *location);
/* A const version of the above. */
extern const struct explicit_location *
get_explicit_location_const (const struct event_location *location);
/* Return a copy of the given SRC location. */
extern event_location_up
copy_event_location (const struct event_location *src);
/* Attempt to convert the input string in *ARGP into an event_location.
ARGP is advanced past any processed input. Always returns a non-nullptr
event_location unique pointer object.
This function may call error() if *ARGP looks like properly formed, but
invalid, input, e.g., if it is called with missing argument parameters
or invalid options.
This function is intended to be used by CLI commands and will parse
explicit locations in a CLI-centric way. Other interfaces should use
string_to_event_location_basic if they want to maintain support for
legacy specifications of probe, address, and linespec locations.
MATCH_TYPE should be either WILD or FULL. If -q/--qualified is specified
in the input string, it will take precedence over this parameter. */
extern event_location_up string_to_event_location
(const char **argp, const struct language_defn *language,
symbol_name_match_type match_type = symbol_name_match_type::WILD);
/* Like string_to_event_location, but does not attempt to parse
explicit locations. MATCH_TYPE indicates how function names should
be matched. */
extern event_location_up
string_to_event_location_basic (const char **argp,
const struct language_defn *language,
symbol_name_match_type match_type);
/* Structure filled in by string_to_explicit_location to aid the
completer. */
struct explicit_completion_info
{
/* Pointer to the last option found. E.g., in "b -sou src.c -fun
func", LAST_OPTION is left pointing at "-fun func". */
const char *last_option = NULL;
/* These point to the start and end of a quoted argument, iff the
last argument was quoted. If parsing finds an incomplete quoted
string (e.g., "break -function 'fun"), then QUOTED_ARG_START is
set to point to the opening \', and QUOTED_ARG_END is left NULL.
If the last option is not quoted, then both are set to NULL. */
const char *quoted_arg_start = NULL;
const char *quoted_arg_end = NULL;
/* True if we saw an explicit location option, as opposed to only
flags that affect both explicit locations and linespecs, like
"-qualified". */
bool saw_explicit_location_option = false;
};
/* Attempt to convert the input string in *ARGP into an explicit location.
ARGP is advanced past any processed input. Returns an event_location
(malloc'd) if an explicit location was successfully found in *ARGP,
NULL otherwise.
If COMPLETION_INFO is NULL, this function may call error() if *ARGP
looks like improperly formed input, e.g., if it is called with
missing argument parameters or invalid options. If COMPLETION_INFO
is not NULL, this function will not throw any exceptions. */
extern event_location_up
string_to_explicit_location (const char **argp,
const struct language_defn *language,
explicit_completion_info *completion_info);
/* A convenience function for testing for unset locations. */
extern int event_location_empty_p (const struct event_location *location);
/* Set the location's string representation. */
extern void
set_event_location_string (struct event_location *location,
std::string &&string);
#endif /* LOCATION_H */