[PATCH 17/24] "backtrace full/no-filters/hide" completer

Pedro Alves
2019-05-22T21:00:44Z

"backtrace"'s completer now completes on command options:

(gdb) bt -[TAB]
-entry-values -full -no-filters -past-main
-frame-arguments -hide -past-entry -raw-frame-arguments

But it doesn't know how to complete on qualifiers:

(gdb) bt fu[TAB]
funlockfile futimens futimes.c
funlockfile.c futimens.c futimesat
futex-internal.h futimes futimesat.c

This commit fixes that:

(gdb) bt fu[TAB]ll
(gdb) bt n[TAB]o-filters
(gdb) bt h[TAB]ide

I considered teaching the gdb::option framework to handle non-'-'
options, but decided it wasn't worth it for this special case, and I'd
rather not make it easy to add new qualifier-like options.

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

* stack.c (parse_backtrace_qualifiers): New.
(backtrace_command): Use it.
(backtrace_command_completer): Complete on qualifiers.

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

* gdb.base/options.exp (test-backtrace): Test completing qualifiers.
---
gdb/stack.c | 84 ++++++++++++++++++++++++++++----------
gdb/testsuite/gdb.base/options.exp | 11 +++++
2 files changed, 73 insertions(+), 22 deletions(-)

diff --git a/gdb/stack.c b/gdb/stack.c
index 3054c797c74..c53d39b1be0 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -2027,6 +2027,45 @@ make_backtrace_options_def_group (frame_print_options *fp_opts,
}};
}

+/* Parse the backtrace command's qualifiers. Returns ARG advanced
+ past the qualifiers, if any. BT_CMD_OPTS, if not null, is used to
+ store the parsed qualifiers. */
+
+static const char *
+parse_backtrace_qualifiers (const char *arg,
+ backtrace_cmd_options *bt_cmd_opts = nullptr)
+{
+ while (true)
+ {
+ const char *save_arg = arg;
+ std::string this_arg = extract_arg (&arg);
+
+ if (this_arg.empty ())
+ return arg;
+
+ if (subset_compare (this_arg.c_str (), "no-filters"))
+ {
+ if (bt_cmd_opts != nullptr)
+ bt_cmd_opts->no_filters = true;
+ }
+ else if (subset_compare (this_arg.c_str (), "full"))
+ {
+ if (bt_cmd_opts != nullptr)
+ bt_cmd_opts->full = true;
+ }
+ else if (subset_compare (this_arg.c_str (), "hide"))
+ {
+ if (bt_cmd_opts != nullptr)
+ bt_cmd_opts->hide = true;
+ }
+ else
+ {
+ /* Not a recognized qualifier, so stop. */
+ return save_arg;
+ }
+ }
+}
+
static void
backtrace_command (const char *arg, int from_tty)
{
@@ -2043,28 +2082,7 @@ backtrace_command (const char *arg, int from_tty)
compatibility. */
if (arg != NULL)
{
- while (true)
- {
- const char *save_arg = arg;
- std::string this_arg = extract_arg (&arg);
-
- if (this_arg.empty ())
- break;
-
- if (subset_compare (this_arg.c_str (), "no-filters"))
- bt_cmd_opts.no_filters = true;
- else if (subset_compare (this_arg.c_str (), "full"))
- bt_cmd_opts.full = true;
- else if (subset_compare (this_arg.c_str (), "hide"))
- bt_cmd_opts.hide = true;
- else
- {
- /* Not a recognized argument, so stop. */
- arg = save_arg;
- break;
- }
- }
-
+ arg = parse_backtrace_qualifiers (arg, &bt_cmd_opts);
if (*arg == '\0')
arg = NULL;
}
@@ -2090,6 +2108,28 @@ backtrace_command_completer (struct cmd_list_element *ignore,
(tracker, &text, gdb::option::PROCESS_OPTIONS_UNKNOWN_IS_OPERAND, group))
return;

+ if (*text != '\0')
+ {
+ const char *p = skip_to_space (text);
+ if (*p == '\0')
+ {
+ static const char *const backtrace_cmd_qualifier_choices[] = {
+ "full", "no-filters", "hide", nullptr,
+ };
+ complete_on_enum (tracker, backtrace_cmd_qualifier_choices,
+ text, text);
+
+ if (tracker.have_completions ())
+ return;
+ }
+ else
+ {
+ const char *cmd = parse_backtrace_qualifiers (text);
+ tracker.advance_custom_word_point_by (cmd - text);
+ text = cmd;
+ }
+ }
+
const char *word = advance_to_expression_complete_word_point (tracker, text);
expression_completer (ignore, tracker, text, word);
}
diff --git a/gdb/testsuite/gdb.base/options.exp b/gdb/testsuite/gdb.base/options.exp
index 6132b1470a4..a4bd686fe5f 100644
--- a/gdb/testsuite/gdb.base/options.exp
+++ b/gdb/testsuite/gdb.base/options.exp
@@ -256,6 +256,17 @@ proc_with_prefix test-backtrace {} {
"-raw-frame-arguments"
}

+ # Test that we complete the qualifiers, if there's any.
+ test_gdb_complete_unique \
+ "backtrace ful" \
+ "backtrace full"
+ test_gdb_complete_unique \
+ "backtrace hid" \
+ "backtrace hide"
+ test_gdb_complete_unique \
+ "backtrace no-fil" \
+ "backtrace no-filters"
+
global binfile
clean_restart $binfile

--
2.14.5