[PATCH v2 03/31] breakpoint.c:commands_command_1 constification and cleanup

Pedro Alves
2016-10-19T01:12:26Z

This is constification needed for next patch. Adjust
commands_command_1 to use std::string too because the "arg" parameter
is currently overwritten and then passed to make_cleanup. The
constification alone would trigger a compile error in the make_cleanup
call otherwise (passing const char * to void * parameter). Using
std::string gets rid of the cleanup in the first place, resulting in
simpler code.

gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <palves@redhat.com>

* breakpoint.c (struct commands_info) <arg>: Constify.
(commands_command_1): Constify 'arg' parameter. Use std::string
and string_printf.
(commands_from_control_command): Constify 'arg' parameter.
(map_breakpoint_numbers): Constify 'args' parameter.
* breakpoint.h (commands_from_control_command): Constify 'arg'
parameter.
---
gdb/breakpoint.c | 42 +++++++++++++++++-------------------------
gdb/breakpoint.h | 2 +-
2 files changed, 18 insertions(+), 26 deletions(-)

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 32d6a95..c9b151f 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -102,8 +102,9 @@ static void disable_command (char *, int);

static void enable_command (char *, int);

-static void map_breakpoint_numbers (char *, void (*) (struct breakpoint *,
- void *),
+static void map_breakpoint_numbers (const char *,
+ void (*) (struct breakpoint *,
+ void *),
void *);

static void ignore_command (char *, int);
@@ -1338,7 +1339,7 @@ struct commands_info
int from_tty;

/* The breakpoint range spec. */
- char *arg;
+ const char *arg;

/* Non-NULL if the body of the commands are being read from this
already-parsed command. */
@@ -1399,7 +1400,7 @@ do_map_commands_command (struct breakpoint *b, void *data)
}

static void
-commands_command_1 (char *arg, int from_tty,
+commands_command_1 (const char *arg, int from_tty,
struct command_line *control)
{
struct cleanup *cleanups;
@@ -1412,32 +1413,22 @@ commands_command_1 (char *arg, int from_tty,
extra reference to the commands that we must clean up. */
cleanups = make_cleanup_decref_counted_command_line (&info.cmd);

+ std::string new_arg;
+
if (arg == NULL || !*arg)
{
if (breakpoint_count - prev_breakpoint_count > 1)
- arg = xstrprintf ("%d-%d", prev_breakpoint_count + 1,
- breakpoint_count);
+ new_arg = string_printf ("%d-%d", prev_breakpoint_count + 1,
+ breakpoint_count);
else if (breakpoint_count > 0)
- arg = xstrprintf ("%d", breakpoint_count);
- else
- {
- /* So that we don't try to free the incoming non-NULL
- argument in the cleanup below. Mapping breakpoint
- numbers will fail in this case. */
- arg = NULL;
- }
+ new_arg = string_printf ("%d", breakpoint_count);
}
else
- /* The command loop has some static state, so we need to preserve
- our argument. */
- arg = xstrdup (arg);
-
- if (arg != NULL)
- make_cleanup (xfree, arg);
+ new_arg = arg;

- info.arg = arg;
+ info.arg = new_arg.c_str ();

- map_breakpoint_numbers (arg, do_map_commands_command, &info);
+ map_breakpoint_numbers (info.arg, do_map_commands_command, &info);

if (info.cmd == NULL)
error (_("No breakpoints specified."));
@@ -1457,7 +1448,7 @@ commands_command (char *arg, int from_tty)
This is used by cli-script.c to DTRT with breakpoint commands
that are part of if and while bodies. */
enum command_control_type
-commands_from_control_command (char *arg, struct command_line *cmd)
+commands_from_control_command (const char *arg, struct command_line *cmd)
{
commands_command_1 (arg, 0, cmd);
return simple_control;
@@ -14769,8 +14760,9 @@ ignore_command (char *args, int from_tty)
whose numbers are given in ARGS. */

static void
-map_breakpoint_numbers (char *args, void (*function) (struct breakpoint *,
- void *),
+map_breakpoint_numbers (const char *args,
+ void (*function) (struct breakpoint *,
+ void *),
void *data)
{
int num;
diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index aaff3d5..ebaf1e3 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -1456,7 +1456,7 @@ extern void enable_breakpoints_after_startup (void);
after they've already read the commands into a struct
command_line. */
extern enum command_control_type commands_from_control_command
- (char *arg, struct command_line *cmd);
+ (const char *arg, struct command_line *cmd);

extern void clear_breakpoint_hit_counts (void);

--
2.5.5