[PATCH v2] dynamic printf
Stan Shebs
stanshebs@earthlink.net
Mon May 14 15:54:00 GMT 2012
On 5/8/12 12:50 AM, Yao Qi wrote:
> Stan,
> See some comments on test case below,
>
>
Thanks for the feedback! Here's what I committed.
Stan
2012-05-14 Stan Shebs <stan@codesourcery.com>
Add dynamic printf.
* breakpoint.h (enum bptype): New type bp_dprintf.
(struct breakpoint): New field extra_string.
(struct breakpoint_ops): Add arg to create_breakpoints_sal.
(create_breakpoint): Add extra_string arg.
* breakpoint.c (dprintf_breakpoint_ops): New.
(is_breakpoint): Add bp_dprintf.
(bpstat_what): Add dprintf case.
(bptype_string): Ditto.
(print_one_breakpoint_location): Ditto.
(init_bp_location): Ditto.
(bkpt_print_mention): Ditto.
(dprintf_style_enums): New array.
(dprintf_style): New global.
(dprintf_function): New global.
(dprintf_channel): New global.
(update_dprintf_command_list): New function.
(update_dprintf_commands): New function.
(init_breakpoint_sal): Add extra_string argument, handle it.
(create_breakpoint_sal): Add extra_string argument.
(create_breakpoints_sal): Add extra_string argument, update callers.
(find_condition_and_thread): Add extra argument.
(create_breakpoint): Add extra_string argument, record it.
(dprintf_command): New function.
(break_command_1): Add arg to create_breakpoint call.
(handle_gnu_v3_exceptions): Ditto.
(trace_command): Ditto.
(ftrace_command): Ditto.
(strace_command): Ditto.
(bkpt_print_mention): Add dprintf case.
(create_breakpoint_sal_default): Add extra_string argument.
(_initialize_breakpoint): Add new commands.
* mi/mi-cmd-break.c (mi_cmd_break_insert): Add arg to call.
* python/py-breakpoint.c (bppy_init): Ditto.
* python/py-finishbreakpoint.c (bpfinishpy_init): Ditto.
* gdb.texinfo (Dynamic Printf): New subsection.
* gdb.base/dprintf.c: New file.
* gdb.base/dprintf.exp: New file.
-------------- next part --------------
Index: NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.518
diff -u -p -r1.518 NEWS
--- NEWS 13 May 2012 11:33:42 -0000 1.518
+++ NEWS 14 May 2012 15:26:53 -0000
@@ -142,6 +142,11 @@
"info auto-load python-scripts", "set auto-load python-scripts on|off"
and "show auto-load python-scripts" counterparts instead.
+ ** "dprintf location,format,args..." creates a dynamic printf, which
+ is basically a breakpoint that does a printf and immediately
+ resumes your program's execution, so it is like a printf that you
+ can insert dynamically at runtime instead of at compiletime.
+
* New targets
Renesas RL78 rl78-*-elf
@@ -200,6 +205,19 @@ set debug auto-load on|off
show debug auto-load
Control display of debugging info for auto-loading the files above.
+set dprintf-style gdb|call
+show dprintf-style
+ Control the way in which a dynamic printf is performed; "gdb" requests
+ a GDB printf command, while "call" causes dprintf to call a function
+ in the inferior.
+
+set dprintf-function <expr>
+show dprintf-function
+set dprintf-channel <expr>
+show dprintf-channel
+ Set the function and optional first argument to the call when using
+ the "call" style of dynamic printf.
+
* New configure options
--with-auto-load-dir
Index: breakpoint.c
===================================================================
RCS file: /cvs/src/src/gdb/breakpoint.c,v
retrieving revision 1.670
diff -u -p -r1.670 breakpoint.c
--- breakpoint.c 27 Apr 2012 20:48:55 -0000 1.670
+++ breakpoint.c 14 May 2012 15:26:53 -0000
@@ -109,7 +109,7 @@ static void create_sals_from_address_def
static void create_breakpoints_sal_default (struct gdbarch *,
struct linespec_result *,
struct linespec_sals *,
- char *, enum bptype,
+ char *, char *, enum bptype,
enum bpdisp, int, int,
int,
const struct breakpoint_ops *,
@@ -294,6 +294,9 @@ struct breakpoint_ops bkpt_breakpoint_op
/* Breakpoints set on probes. */
static struct breakpoint_ops bkpt_probe_breakpoint_ops;
+/* Dynamic printf class type. */
+static struct breakpoint_ops dprintf_breakpoint_ops;
+
/* A reference-counted struct command_line. This lets multiple
breakpoints share a single command list. */
struct counted_command_line
@@ -1494,7 +1497,8 @@ int
is_breakpoint (const struct breakpoint *bpt)
{
return (bpt->type == bp_breakpoint
- || bpt->type == bp_hardware_breakpoint);
+ || bpt->type == bp_hardware_breakpoint
+ || bpt->type == bp_dprintf);
}
/* Return true if BPT is of any hardware watchpoint kind. */
@@ -5178,6 +5182,11 @@ bpstat_what (bpstat bs_head)
PC of the former breakpoint. */
this_action = BPSTAT_WHAT_KEEP_CHECKING;
break;
+
+ case bp_dprintf:
+ this_action = BPSTAT_WHAT_STOP_SILENT;
+ break;
+
default:
internal_error (__FILE__, __LINE__,
_("bpstat_what: unhandled bptype %d"), (int) bptype);
@@ -5442,6 +5451,7 @@ bptype_string (enum bptype type)
{bp_tracepoint, "tracepoint"},
{bp_fast_tracepoint, "fast tracepoint"},
{bp_static_tracepoint, "static tracepoint"},
+ {bp_dprintf, "dprintf"},
{bp_jit_event, "jit events"},
{bp_gnu_ifunc_resolver, "STT_GNU_IFUNC resolver"},
{bp_gnu_ifunc_resolver_return, "STT_GNU_IFUNC resolver return"},
@@ -5582,6 +5592,7 @@ print_one_breakpoint_location (struct br
case bp_tracepoint:
case bp_fast_tracepoint:
case bp_static_tracepoint:
+ case bp_dprintf:
case bp_jit_event:
case bp_gnu_ifunc_resolver:
case bp_gnu_ifunc_resolver_return:
@@ -6444,6 +6455,7 @@ init_bp_location (struct bp_location *lo
case bp_exception_master:
case bp_gnu_ifunc_resolver:
case bp_gnu_ifunc_resolver_return:
+ case bp_dprintf:
loc->loc_type = bp_loc_software_breakpoint;
mark_breakpoint_location_modified (loc);
break;
@@ -8382,7 +8394,122 @@ bp_loc_is_permanent (struct bp_location
return retval;
}
+/* The style in which to perform a dynamic printf. This is a user
+ option because different output options have different tradeoffs;
+ if GDB does the printing, there is better error handling if there
+ is a problem with any of the arguments, but using an inferior
+ function lets you have special-purpose printers and sending of
+ output to the same place as compiled-in print functions. (Future
+ styles may include the ability to do a target-side printf.) */
+
+static const char dprintf_style_gdb[] = "gdb";
+static const char dprintf_style_call[] = "call";
+static const char *const dprintf_style_enums[] = {
+ dprintf_style_gdb,
+ dprintf_style_call,
+ NULL
+};
+static const char *dprintf_style = dprintf_style_gdb;
+
+/* The function to use for dynamic printf if the preferred style is to
+ call into the inferior. The value is simply a string that is
+ copied into the command, so it can be anything that GDB can
+ evaluate to a callable address, not necessarily a function name. */
+
+static char *dprintf_function = "";
+
+/* The channel to use for dynamic printf if the preferred style is to
+ call into the inferior; if a nonempty string, it will be passed to
+ the call as the first argument, with the format string as the
+ second. As with the dprintf function, this can be anything that
+ GDB knows how to evaluate, so in addition to common choices like
+ "stderr", this could be an app-specific expression like
+ "mystreams[curlogger]". */
+
+static char *dprintf_channel = "";
+
+/* Build a command list for the dprintf corresponding to the current
+ settings of the dprintf style options. */
+
+static void
+update_dprintf_command_list (struct breakpoint *b)
+{
+ char *dprintf_args = b->extra_string;
+ char *printf_line = NULL;
+
+ if (!dprintf_args)
+ return;
+
+ dprintf_args = skip_spaces (dprintf_args);
+
+ /* Allow a comma, as it may have terminated a location, but don't
+ insist on it. */
+ if (*dprintf_args == ',')
+ ++dprintf_args;
+ dprintf_args = skip_spaces (dprintf_args);
+
+ if (*dprintf_args != '"')
+ error (_("Bad format string, missing '\"'."));
+
+ if (strcmp (dprintf_style, "gdb") == 0)
+ printf_line = xstrprintf ("printf %s", dprintf_args);
+ else if (strcmp (dprintf_style, "call") == 0)
+ {
+ if (!dprintf_function)
+ error (_("No function supplied for dprintf call"));
+
+ if (dprintf_channel && strlen (dprintf_channel) > 0)
+ printf_line = xstrprintf ("call (void) %s (%s,%s)",
+ dprintf_function,
+ dprintf_channel,
+ dprintf_args);
+ else
+ printf_line = xstrprintf ("call (void) %s (%s)",
+ dprintf_function,
+ dprintf_args);
+ }
+ else
+ internal_error (__FILE__, __LINE__,
+ _("Invalid dprintf style."));
+
+ /* Manufacture a printf/continue sequence. */
+ if (printf_line)
+ {
+ struct command_line *printf_cmd_line, *cont_cmd_line = NULL;
+
+ cont_cmd_line = xmalloc (sizeof (struct command_line));
+ cont_cmd_line->control_type = simple_control;
+ cont_cmd_line->body_count = 0;
+ cont_cmd_line->body_list = NULL;
+ cont_cmd_line->next = NULL;
+ cont_cmd_line->line = xstrdup ("continue");
+
+ printf_cmd_line = xmalloc (sizeof (struct command_line));
+ printf_cmd_line->control_type = simple_control;
+ printf_cmd_line->body_count = 0;
+ printf_cmd_line->body_list = NULL;
+ printf_cmd_line->next = cont_cmd_line;
+ printf_cmd_line->line = printf_line;
+
+ breakpoint_set_commands (b, printf_cmd_line);
+ }
+}
+
+/* Update all dprintf commands, making their command lists reflect
+ current style settings. */
+static void
+update_dprintf_commands (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+ struct breakpoint *b;
+
+ ALL_BREAKPOINTS (b)
+ {
+ if (b->type == bp_dprintf)
+ update_dprintf_command_list (b);
+ }
+}
/* Create a breakpoint with SAL as location. Use ADDR_STRING
as textual description of the location, and COND_STRING
@@ -8392,6 +8519,7 @@ static void
init_breakpoint_sal (struct breakpoint *b, struct gdbarch *gdbarch,
struct symtabs_and_lines sals, char *addr_string,
char *filter, char *cond_string,
+ char *extra_string,
enum bptype type, enum bpdisp disposition,
int thread, int task, int ignore_count,
const struct breakpoint_ops *ops, int from_tty,
@@ -8438,6 +8566,7 @@ init_breakpoint_sal (struct breakpoint *
b->task = task;
b->cond_string = cond_string;
+ b->extra_string = extra_string;
b->ignore_count = ignore_count;
b->enable_state = enabled ? bp_enabled : bp_disabled;
b->disposition = disposition;
@@ -8502,6 +8631,18 @@ init_breakpoint_sal (struct breakpoint *
if (*arg)
error (_("Garbage %s follows condition"), arg);
}
+
+ /* Dynamic printf requires and uses additional arguments on the
+ command line, otherwise it's an error. */
+ if (type == bp_dprintf)
+ {
+ if (b->extra_string)
+ update_dprintf_command_list (b);
+ else
+ error (_("Format string required"));
+ }
+ else if (b->extra_string)
+ error (_("Garbage %s at end of command"), b->extra_string);
}
b->display_canonical = display_canonical;
@@ -8519,6 +8660,7 @@ static void
create_breakpoint_sal (struct gdbarch *gdbarch,
struct symtabs_and_lines sals, char *addr_string,
char *filter, char *cond_string,
+ char *extra_string,
enum bptype type, enum bpdisp disposition,
int thread, int task, int ignore_count,
const struct breakpoint_ops *ops, int from_tty,
@@ -8542,7 +8684,7 @@ create_breakpoint_sal (struct gdbarch *g
init_breakpoint_sal (b, gdbarch,
sals, addr_string,
- filter, cond_string,
+ filter, cond_string, extra_string,
type, disposition,
thread, task, ignore_count,
ops, from_tty,
@@ -8571,7 +8713,7 @@ create_breakpoint_sal (struct gdbarch *g
static void
create_breakpoints_sal (struct gdbarch *gdbarch,
struct linespec_result *canonical,
- char *cond_string,
+ char *cond_string, char *extra_string,
enum bptype type, enum bpdisp disposition,
int thread, int task, int ignore_count,
const struct breakpoint_ops *ops, int from_tty,
@@ -8597,7 +8739,8 @@ create_breakpoints_sal (struct gdbarch *
create_breakpoint_sal (gdbarch, lsal->sals,
addr_string,
filter_string,
- cond_string, type, disposition,
+ cond_string, extra_string,
+ type, disposition,
thread, task, ignore_count, ops,
from_tty, enabled, internal, flags,
canonical->special_display);
@@ -8734,7 +8877,8 @@ check_fast_tracepoint_sals (struct gdbar
If no thread is found, *THREAD is set to -1. */
static void
find_condition_and_thread (char *tok, CORE_ADDR pc,
- char **cond_string, int *thread, int *task)
+ char **cond_string, int *thread, int *task,
+ char **rest)
{
*cond_string = NULL;
*thread = -1;
@@ -8746,7 +8890,13 @@ find_condition_and_thread (char *tok, CO
char *cond_end = NULL;
tok = skip_spaces (tok);
-
+
+ if ((*tok == '"' || *tok == ',') && rest)
+ {
+ *rest = savestring (tok, strlen (tok));
+ return;
+ }
+
end_tok = skip_to_space (tok);
toklen = end_tok - tok;
@@ -8786,6 +8936,11 @@ find_condition_and_thread (char *tok, CO
if (!valid_task_id (*task))
error (_("Unknown task %d."), *task);
}
+ else if (rest)
+ {
+ *rest = savestring (tok, strlen (tok));
+ tok += toklen;
+ }
else
error (_("Junk at end of arguments."));
}
@@ -8853,7 +9008,8 @@ decode_static_tracepoint_spec (char **ar
int
create_breakpoint (struct gdbarch *gdbarch,
- char *arg, char *cond_string, int thread,
+ char *arg, char *cond_string,
+ int thread, char *extra_string,
int parse_condition_and_thread,
int tempflag, enum bptype type_wanted,
int ignore_count,
@@ -8975,16 +9131,22 @@ create_breakpoint (struct gdbarch *gdbar
if (parse_condition_and_thread)
{
+ char *rest;
/* Here we only parse 'arg' to separate condition
from thread number, so parsing in context of first
sal is OK. When setting the breakpoint we'll
re-parse it in context of each sal. */
cond_string = NULL;
thread = -1;
+ rest = NULL;
find_condition_and_thread (arg, lsal->sals.sals[0].pc, &cond_string,
- &thread, &task);
+ &thread, &task, &rest);
if (cond_string)
make_cleanup (xfree, cond_string);
+ if (rest)
+ make_cleanup (xfree, rest);
+ if (rest)
+ extra_string = rest;
}
else
{
@@ -8994,10 +9156,16 @@ create_breakpoint (struct gdbarch *gdbar
cond_string = xstrdup (cond_string);
make_cleanup (xfree, cond_string);
}
+ /* Create a private copy of any extra string. */
+ if (extra_string)
+ {
+ extra_string = xstrdup (extra_string);
+ make_cleanup (xfree, extra_string);
+ }
}
ops->create_breakpoints_sal (gdbarch, &canonical, lsal,
- cond_string, type_wanted,
+ cond_string, extra_string, type_wanted,
tempflag ? disp_del : disp_donttouch,
thread, task, ignore_count, ops,
from_tty, enabled, internal, flags);
@@ -9022,6 +9190,7 @@ create_breakpoint (struct gdbarch *gdbar
b->addr_string = copy_arg;
b->cond_string = NULL;
+ b->extra_string = NULL;
b->ignore_count = ignore_count;
b->disposition = tempflag ? disp_del : disp_donttouch;
b->condition_not_parsed = 1;
@@ -9077,7 +9246,7 @@ break_command_1 (char *arg, int flag, in
create_breakpoint (get_current_arch (),
arg,
- NULL, 0, 1 /* parse arg */,
+ NULL, 0, NULL, 1 /* parse arg */,
tempflag, type_wanted,
0 /* Ignore count */,
pending_break_support,
@@ -9242,6 +9411,29 @@ stopat_command (char *arg, int from_tty)
break_command_1 (arg, 0, from_tty);
}
+void dprintf_command (char *arg, int from_tty);
+
+/* The dynamic printf command is mostly like a regular breakpoint, but
+ with a prewired command list consisting of a single output command,
+ built from extra arguments supplied on the dprintf command
+ line. */
+
+void
+dprintf_command (char *arg, int from_tty)
+{
+ create_breakpoint (get_current_arch (),
+ arg,
+ NULL, 0, NULL, 1 /* parse arg */,
+ 0, bp_dprintf,
+ 0 /* Ignore count */,
+ pending_break_support,
+ &dprintf_breakpoint_ops,
+ from_tty,
+ 1 /* enabled */,
+ 0 /* internal */,
+ 0);
+}
+
/* Implement the "breakpoint_hit" breakpoint_ops method for
ranged breakpoints. */
@@ -10953,7 +11145,7 @@ handle_gnu_v3_exceptions (int tempflag,
trigger_func_name = "__cxa_throw";
create_breakpoint (get_current_arch (),
- trigger_func_name, cond_string, -1,
+ trigger_func_name, cond_string, -1, NULL,
0 /* condition and thread are valid. */,
tempflag, bp_breakpoint,
0,
@@ -12182,6 +12374,7 @@ base_breakpoint_create_breakpoints_sal (
struct linespec_result *c,
struct linespec_sals *lsal,
char *cond_string,
+ char *extra_string,
enum bptype type_wanted,
enum bpdisp disposition,
int thread,
@@ -12344,6 +12537,9 @@ bkpt_print_mention (struct breakpoint *b
case bp_hardware_breakpoint:
printf_filtered (_("Hardware assisted breakpoint %d"), b->number);
break;
+ case bp_dprintf:
+ printf_filtered (_("Dprintf %d"), b->number);
+ break;
}
say_where (b);
@@ -12384,6 +12580,7 @@ bkpt_create_breakpoints_sal (struct gdba
struct linespec_result *canonical,
struct linespec_sals *lsal,
char *cond_string,
+ char *extra_string,
enum bptype type_wanted,
enum bpdisp disposition,
int thread,
@@ -12393,7 +12590,8 @@ bkpt_create_breakpoints_sal (struct gdba
int internal, unsigned flags)
{
create_breakpoints_sal_default (gdbarch, canonical, lsal,
- cond_string, type_wanted,
+ cond_string, extra_string,
+ type_wanted,
disposition, thread, task,
ignore_count, ops, from_tty,
enabled, internal, flags);
@@ -12705,6 +12903,7 @@ tracepoint_create_breakpoints_sal (struc
struct linespec_result *canonical,
struct linespec_sals *lsal,
char *cond_string,
+ char *extra_string,
enum bptype type_wanted,
enum bpdisp disposition,
int thread,
@@ -12714,7 +12913,8 @@ tracepoint_create_breakpoints_sal (struc
int internal, unsigned flags)
{
create_breakpoints_sal_default (gdbarch, canonical, lsal,
- cond_string, type_wanted,
+ cond_string, extra_string,
+ type_wanted,
disposition, thread, task,
ignore_count, ops, from_tty,
enabled, internal, flags);
@@ -12778,6 +12978,7 @@ strace_marker_create_breakpoints_sal (st
struct linespec_result *canonical,
struct linespec_sals *lsal,
char *cond_string,
+ char *extra_string,
enum bptype type_wanted,
enum bpdisp disposition,
int thread,
@@ -12811,7 +13012,8 @@ strace_marker_create_breakpoints_sal (st
tp = XCNEW (struct tracepoint);
init_breakpoint_sal (&tp->base, gdbarch, expanded,
addr_string, NULL,
- cond_string, type_wanted, disposition,
+ cond_string, extra_string,
+ type_wanted, disposition,
thread, task, ignore_count, ops,
from_tty, enabled, internal, flags,
canonical->special_display);
@@ -13438,13 +13640,17 @@ addr_string_to_sals (struct breakpoint *
char *cond_string = 0;
int thread = -1;
int task = 0;
+ char *extra_string = NULL;
find_condition_and_thread (s, sals.sals[0].pc,
- &cond_string, &thread, &task);
+ &cond_string, &thread, &task,
+ &extra_string);
if (cond_string)
b->cond_string = cond_string;
b->thread = thread;
b->task = task;
+ if (extra_string)
+ b->extra_string = extra_string;
b->condition_not_parsed = 0;
}
@@ -13512,6 +13718,7 @@ create_breakpoints_sal_default (struct g
struct linespec_result *canonical,
struct linespec_sals *lsal,
char *cond_string,
+ char *extra_string,
enum bptype type_wanted,
enum bpdisp disposition,
int thread,
@@ -13521,6 +13728,7 @@ create_breakpoints_sal_default (struct g
int internal, unsigned flags)
{
create_breakpoints_sal (gdbarch, canonical, cond_string,
+ extra_string,
type_wanted, disposition,
thread, task, ignore_count, ops, from_tty,
enabled, internal, flags);
@@ -14394,7 +14602,7 @@ trace_command (char *arg, int from_tty)
if (create_breakpoint (get_current_arch (),
arg,
- NULL, 0, 1 /* parse arg */,
+ NULL, 0, NULL, 1 /* parse arg */,
0 /* tempflag */,
bp_tracepoint /* type_wanted */,
0 /* Ignore count */,
@@ -14411,7 +14619,7 @@ ftrace_command (char *arg, int from_tty)
{
if (create_breakpoint (get_current_arch (),
arg,
- NULL, 0, 1 /* parse arg */,
+ NULL, 0, NULL, 1 /* parse arg */,
0 /* tempflag */,
bp_fast_tracepoint /* type_wanted */,
0 /* Ignore count */,
@@ -14439,7 +14647,7 @@ strace_command (char *arg, int from_tty)
if (create_breakpoint (get_current_arch (),
arg,
- NULL, 0, 1 /* parse arg */,
+ NULL, 0, NULL, 1 /* parse arg */,
0 /* tempflag */,
bp_static_tracepoint /* type_wanted */,
0 /* Ignore count */,
@@ -14504,7 +14712,8 @@ create_tracepoint_from_upload (struct up
if (!create_breakpoint (get_current_arch (),
addr_str,
- utp->cond_string, -1, 0 /* parse cond/thread */,
+ utp->cond_string, -1, NULL,
+ 0 /* parse cond/thread */,
0 /* tempflag */,
utp->type /* type_wanted */,
0 /* Ignore count */,
@@ -15260,6 +15469,14 @@ initialize_breakpoint_ops (void)
ops->print_one = print_one_catch_solib;
ops->print_mention = print_mention_catch_solib;
ops->print_recreate = print_recreate_catch_solib;
+
+ ops = &dprintf_breakpoint_ops;
+ *ops = bkpt_base_breakpoint_ops;
+ ops->re_set = bkpt_re_set;
+ ops->resources_needed = bkpt_resources_needed;
+ ops->print_it = bkpt_print_it;
+ ops->print_mention = bkpt_print_mention;
+ ops->print_recreate = bkpt_print_recreate;
}
void
@@ -15842,6 +16059,44 @@ The breakpoint will stop execution of th
an instruction at any address within the [START-LOCATION, END-LOCATION]\n\
range (including START-LOCATION and END-LOCATION)."));
+ c = add_com ("dprintf", class_breakpoint, dprintf_command, _("\
+Set a dynamic printf at specified line or function.\n\
+dprintf location,format string,arg1,arg2,...\n\
+location may be a line number, function name, or \"*\" and an address.\n\
+If a line number is specified, break at start of code for that line.\n\
+If a function is specified, break at start of code for that function.\n\
+"));
+ set_cmd_completer (c, location_completer);
+
+ add_setshow_enum_cmd ("dprintf-style", class_support,
+ dprintf_style_enums, &dprintf_style, _("\
+Set the style of usage for dynamic printf."), _("\
+Show the style of usage for dynamic printf."), _("\
+This setting chooses how GDB will do a dynamic printf.\n\
+If the value is \"gdb\", then the printing is done by GDB to its own\n\
+console, as with the \"printf\" command.\n\
+If the value is \"call\", the print is done by calling a function in your\n\
+program; by default printf(), but you can choose a different function or\n\
+output stream by setting dprintf-function and dprintf-channel."),
+ update_dprintf_commands, NULL,
+ &setlist, &showlist);
+
+ dprintf_function = xstrdup ("printf");
+ add_setshow_string_cmd ("dprintf-function", class_support,
+ &dprintf_function, _("\
+Set the function to use for dynamic printf"), _("\
+Show the function to use for dynamic printf"), NULL,
+ update_dprintf_commands, NULL,
+ &setlist, &showlist);
+
+ dprintf_channel = xstrdup ("");
+ add_setshow_string_cmd ("dprintf-channel", class_support,
+ &dprintf_channel, _("\
+Set the channel to use for dynamic printf"), _("\
+Show the channel to use for dynamic printf"), NULL,
+ update_dprintf_commands, NULL,
+ &setlist, &showlist);
+
automatic_hardware_breakpoints = 1;
observer_attach_about_to_proceed (breakpoint_about_to_proceed);
Index: breakpoint.h
===================================================================
RCS file: /cvs/src/src/gdb/breakpoint.h,v
retrieving revision 1.181
diff -u -p -r1.181 breakpoint.h
--- breakpoint.h 27 Apr 2012 20:47:51 -0000 1.181
+++ breakpoint.h 14 May 2012 15:26:53 -0000
@@ -154,6 +154,13 @@ enum bptype
bp_fast_tracepoint,
bp_static_tracepoint,
+ /* A dynamic printf stops at the given location, does a formatted
+ print, then automatically continues. (Although this is sort of
+ like a macro packaging up standard breakpoint functionality,
+ GDB doesn't have a way to construct types of breakpoint from
+ elements of behavior.) */
+ bp_dprintf,
+
/* Event for JIT compiled code generation or deletion. */
bp_jit_event,
@@ -552,6 +559,7 @@ struct breakpoint_ops
void (*create_breakpoints_sal) (struct gdbarch *,
struct linespec_result *,
struct linespec_sals *, char *,
+ char *,
enum bptype, enum bpdisp, int, int,
int, const struct breakpoint_ops *,
int, int, int, unsigned);
@@ -674,8 +682,9 @@ struct breakpoint
/* String form of the breakpoint condition (malloc'd), or NULL if
there is no condition. */
char *cond_string;
- /* String form of exp to use for displaying to the user
- (malloc'd), or NULL if none. */
+
+ /* String form of extra parameters, or NULL if there are none. */
+ char *extra_string;
/* Holds the address of the related watchpoint_scope breakpoint
when using watchpoints on local variables (might the concept of
@@ -1210,6 +1219,7 @@ enum breakpoint_create_flags
extern int create_breakpoint (struct gdbarch *gdbarch, char *arg,
char *cond_string, int thread,
+ char *extra_string,
int parse_condition_and_thread,
int tempflag, enum bptype wanted_type,
int ignore_count,
Index: doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.963
diff -u -p -r1.963 gdb.texinfo
--- doc/gdb.texinfo 13 May 2012 11:33:43 -0000 1.963
+++ doc/gdb.texinfo 14 May 2012 15:26:54 -0000
@@ -3341,6 +3341,7 @@ all breakpoints in that range are operat
* Disabling:: Disabling breakpoints
* Conditions:: Break conditions
* Break Commands:: Breakpoint command lists
+* Dynamic Printf:: Dynamic printf
* Save Breakpoints:: How to save breakpoints in a file
* Static Probe Points:: Listing static probe points
* Error in Breakpoints:: ``Cannot insert breakpoints''
@@ -4628,6 +4629,89 @@ cont
end
@end smallexample
+@node Dynamic Printf
+@subsection Dynamic Printf
+
+@cindex dynamic printf
+@cindex dprintf
+The dynamic printf command @code{dprintf} combines a breakpoint with
+formatted printing of your program's data to give you the effect of
+inserting @code{printf} calls into your program on-the-fly, without
+having to recompile it.
+
+In its most basic form, the output goes to the GDB console. However,
+you can set the variable @code{dprintf-style} for alternate handling.
+For instance, you can ask to format the output by calling your
+program's @code{printf} function. This has the advantage that the
+characters go to the program's output device, so they can recorded in
+redirects to files and so forth.
+
+@table @code
+@kindex dprintf
+@item dprintf @var{location},@var{template},@var{expression}[,@var{expression}@dots{}]
+Whenever execution reaches @var{location}, print the values of one or
+more @var{expressions} under the control of the string @var{template}.
+To print several values, separate them with commas.
+
+@item set dprintf-style @var{style}
+Set the dprintf output to be handled in one of several different
+styles enumerated below. A change of style affects all existing
+dynamic printfs immediately. (If you need individual control over the
+print commands, simply define normal breakpoints with
+explicitly-supplied command lists.)
+
+@item gdb
+@kindex dprintf-style gdb
+Handle the output using the @value{GDBN} @code{printf} command.
+
+@item call
+@kindex dprintf-style call
+Handle the output by calling a function in your program (normally
+@code{printf}).
+
+@item set dprintf-function @var{function}
+Set the function to call if the dprintf style is @code{call}. By
+default its value is @code{printf}. You may set it to any expression.
+that @value{GDBN} can evaluate to a function, as per the @code{call}
+command.
+
+@item set dprintf-channel @var{channel}
+Set a ``channel'' for dprintf. If set to a non-empty value,
+@value{GDBN} will evaluate it as an expression and pass the result as
+a first argument to the @code{dprintf-function}, in the manner of
+@code{fprintf} and similar functions. Otherwise, the dprintf format
+string will be the first argument, in the manner of @code{printf}.
+
+As an example, if you wanted @code{dprintf} output to go to a logfile
+that is a standard I/O stream assigned to the variable @code{mylog},
+you could do the following:
+
+@example
+(gdb) set dprintf-style call
+(gdb) set dprintf-function fprintf
+(gdb) set dprintf-channel mylog
+(gdb) dprintf 25,"at line 25, glob=%d\n",glob
+Dprintf 1 at 0x123456: file main.c, line 25.
+(gdb) info break
+1 dprintf keep y 0x00123456 in main at main.c:25
+ call (void) fprintf (mylog,"at line 25, glob=%d\n",glob)
+ continue
+(gdb)
+@end example
+
+Note that the @code{info break} displays the dynamic printf commands
+as normal breakpoint commands; you can thus easily see the effect of
+the variable settings.
+
+@end table
+
+@value{GDBN} does not check the validity of function and channel,
+relying on you to supply values that are meaningful for the contexts
+in which they are being used. For instance, the function and channel
+may be the values of local variables, but if that is the case, then
+all enabled dynamic prints must be at locations within the scope of
+those locals. If evaluation fails, @value{GDBN} will report an error.
+
@node Save Breakpoints
@subsection How to save breakpoints to a file
Index: python/py-breakpoint.c
===================================================================
RCS file: /cvs/src/src/gdb/python/py-breakpoint.c,v
retrieving revision 1.33
diff -u -p -r1.33 py-breakpoint.c
--- python/py-breakpoint.c 13 Mar 2012 13:30:42 -0000 1.33
+++ python/py-breakpoint.c 14 May 2012 15:26:54 -0000
@@ -622,7 +622,7 @@ bppy_init (PyObject *self, PyObject *arg
case bp_breakpoint:
{
create_breakpoint (python_gdbarch,
- copy, NULL, -1,
+ copy, NULL, -1, NULL,
0,
0, bp_breakpoint,
0,
Index: python/py-finishbreakpoint.c
===================================================================
RCS file: /cvs/src/src/gdb/python/py-finishbreakpoint.c,v
retrieving revision 1.4
diff -u -p -r1.4 py-finishbreakpoint.c
--- python/py-finishbreakpoint.c 13 Mar 2012 13:30:42 -0000 1.4
+++ python/py-finishbreakpoint.c 14 May 2012 15:26:54 -0000
@@ -281,7 +281,7 @@ bpfinishpy_init (PyObject *self, PyObjec
addr_str = small_buf;
create_breakpoint (python_gdbarch,
- addr_str, NULL, thread,
+ addr_str, NULL, thread, NULL,
0,
1 /*temp_flag*/,
bp_breakpoint,
Index: mi/mi-cmd-break.c
===================================================================
RCS file: /cvs/src/src/gdb/mi/mi-cmd-break.c,v
retrieving revision 1.51
diff -u -p -r1.51 mi-cmd-break.c
--- mi/mi-cmd-break.c 13 Mar 2012 13:30:42 -0000 1.51
+++ mi/mi-cmd-break.c 14 May 2012 15:26:54 -0000
@@ -164,6 +164,7 @@ mi_cmd_break_insert (char *command, char
: (hardware ? bp_hardware_breakpoint : bp_breakpoint));
create_breakpoint (get_current_arch (), address, condition, thread,
+ NULL,
0 /* condition and thread are valid. */,
temp_p, type_wanted,
ignore_count,
Index: testsuite/gdb.base/dprintf.c
===================================================================
RCS file: testsuite/gdb.base/dprintf.c
diff -N testsuite/gdb.base/dprintf.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.base/dprintf.c 14 May 2012 15:26:54 -0000
@@ -0,0 +1,44 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright (C) 2012 Free Software Foundation, Inc.
+
+ 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/>. */
+
+#include <stdio.h>
+
+static int g;
+
+void
+foo (int arg)
+{
+ g += arg;
+ g *= 2; /* set dprintf 1 here */
+ g /= 2.5; /* set breakpoint 1 here */
+}
+
+int
+main (int argc, char *argv[])
+{
+ int loc = 1234;
+
+ /* Ensure these functions are available. */
+ printf ("kickoff\n");
+ fprintf (stderr, "also to stderr\n");
+
+ foo (loc++);
+ foo (loc++);
+ foo (loc++);
+ return g;
+}
+
Index: testsuite/gdb.base/dprintf.exp
===================================================================
RCS file: testsuite/gdb.base/dprintf.exp
diff -N testsuite/gdb.base/dprintf.exp
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.base/dprintf.exp 14 May 2012 15:26:54 -0000
@@ -0,0 +1,89 @@
+# Copyright (C) 2012 Free Software Foundation, Inc.
+
+# 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/>.
+
+
+if { [prepare_for_testing dprintf.exp "dprintf" {} {debug}] } {
+ return -1
+}
+
+set srcfile dprintf.c
+
+set bp_location1 [gdb_get_line_number "set breakpoint 1 here"]
+set dp_location1 [gdb_get_line_number "set dprintf 1 here"]
+
+gdb_breakpoint "main"
+gdb_run_cmd
+
+gdb_test "dprintf" "Format string required"
+
+gdb_test "dprintf foo" "Format string required"
+
+gdb_test "dprintf 29" "Format string required"
+
+delete_breakpoints
+
+gdb_breakpoint "main"
+
+gdb_test "dprintf foo,\"At foo entry\\n\"" \
+ "Dprintf .*"
+
+gdb_test "dprintf $dp_location1,\"arg=%d, g=%d\\n\", arg, g" \
+ "Dprintf .*"
+
+gdb_test "break $bp_location1" \
+ "Breakpoint .*"
+
+gdb_run_cmd
+
+gdb_test "" "Breakpoint"
+
+gdb_test "continue" "At foo entry.*arg=1234, g=1234.*" "1st dprintf, gdb"
+
+gdb_test "continue" "At foo entry.*arg=1235, g=2222.*" "2nd dprintf, gdb"
+
+# The "call" style depends on having I/O functions available, so test.
+
+if ![target_info exists gdb,noinferiorio] {
+
+ # Now switch styles and rerun; in the absence of redirection the
+ # output should be the same.
+
+ gdb_test_no_output "set dprintf-style call" "Set dprintf style to call"
+
+ gdb_run_cmd
+
+ gdb_test "" "Breakpoint"
+
+ gdb_test "continue" "At foo entry.*arg=1234, g=1234.*" "1st dprintf, call"
+
+ gdb_test "continue" "At foo entry.*arg=1235, g=2222.*" "2nd dprintf, call"
+
+ gdb_test_no_output "set dprintf-function fprintf" "Set dprintf function"
+ gdb_test_no_output "set dprintf-channel stderr" "Set dprintf channel"
+
+ gdb_run_cmd
+
+ gdb_test "" "Breakpoint"
+
+ gdb_test "continue" "At foo entry.*arg=1234, g=1234.*" \
+ "1st dprintf, fprintf"
+
+ gdb_test "continue" "At foo entry.*arg=1235, g=2222.*" \
+ "2nd dprintf, fprintf"
+}
+
+gdb_test "set dprintf-style foobar" "Undefined item: \"foobar\"." \
+ "Set dprintf style to an unrecognized type"
+
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