[pushed] Fix GDB builds that include the simulator (Re: [PATCH 11/40] Introduce class completion_tracker & rewrite completion<->readline interaction)

Pedro Alves
2017-07-18T10:42:56Z

On 07/18/2017 10:04 AM, Pedro Alves wrote:
> sim_command_completer needs to be adjusted to the new interface.
> I'm building a --target-none-eabi gdb to fix this.

Thanks again for reporting. Fixed with the patch below.

Pedro Alves

From 386535dd91432b784f6a46f8a92c6a599ba30174 Mon Sep 17 00:00:00 2001
From: Pedro Alves <palves@redhat.com>
Date: Tue, 18 Jul 2017 11:38:17 +0100
Subject: [PATCH] Fix GDB builds that include the simulator
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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The completer rewrite series missed adjusting target sim to the new
completion_tracker interface.

src/gdb/remote-sim.c: In function Â‘void _initialize_remote_sim()Â’:
src/gdb/remote-sim.c:1350:46: error: invalid conversion from Â‘VEC_char_ptr* (*)(cmd_list_element*, const char*, const char*)Â’ to Â‘void (*)(cmd_list_element*, completion_tracker&, const char*, const char*)Â’ [-fpermissive]
set_cmd_completer (c, sim_command_completer);
^

This commit fixes it, and also takes care to be exception safe (the
previous code would leak if growing the VEC throws).

Tested manually with a --target=arm-none-eabi build.

gdb/ChangeLog:
2017-07-18 Pedro Alves <palves@redhat.com>

* remote-sim.c (sim_command_completer): Adjust to work with a
completion_tracker instead of a VEC.
---
gdb/ChangeLog | 5 +++++
gdb/remote-sim.c | 48 +++++++++++++++++++++++++++++++++---------------
2 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 20344f7..66ae527 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2017-07-18 Pedro Alves <palves@redhat.com>
+
+ * remote-sim.c (sim_command_completer): Adjust to work with a
+ completion_tracker instead of a VEC.
+
2017-07-17 Pedro Alves <palves@redhat.com>

* completer.c (complete_source_filenames): New function.
diff --git a/gdb/remote-sim.c b/gdb/remote-sim.c
index 13137ab..508e2c2 100644
--- a/gdb/remote-sim.c
+++ b/gdb/remote-sim.c
@@ -1220,30 +1220,48 @@ simulator_command (char *args, int from_tty)
registers_changed ();
}

-static VEC (char_ptr) *
-sim_command_completer (struct cmd_list_element *ignore, const char *text,
- const char *word)
+static void
+sim_command_completer (struct cmd_list_element *ignore,
+ completion_tracker &tracker,
+ const char *text, const char *word)
{
struct sim_inferior_data *sim_data;
- char **tmp;
- int i;
- VEC (char_ptr) *result = NULL;

sim_data = ((struct sim_inferior_data *)
inferior_data (current_inferior (), sim_inferior_data_key));
if (sim_data == NULL || sim_data->gdbsim_desc == NULL)
- return NULL;
+ return;

- tmp = sim_complete_command (sim_data->gdbsim_desc, text, word);
- if (tmp == NULL)
- return NULL;
+ /* sim_complete_command returns a NULL-terminated malloc'ed array of
+ malloc'ed strings. */
+ struct sim_completions_deleter
+ {
+ void operator() (char **ptr) const
+ {
+ for (size_t i = 0; ptr[i] != NULL; i++)
+ xfree (ptr[i]);
+ xfree (ptr);
+ }
+ };
+
+ std::unique_ptr<char *[], sim_completions_deleter> sim_completions
+ (sim_complete_command (sim_data->gdbsim_desc, text, word));
+ if (sim_completions == NULL)
+ return;

- /* Transform the array into a VEC, and then free the array. */
- for (i = 0; tmp[i] != NULL; i++)
- VEC_safe_push (char_ptr, result, tmp[i]);
- xfree (tmp);
+ /* Count the elements and add completions from tail to head because
+ below we'll swap elements out of the array in case add_completion
+ throws and the deleter deletes until it finds a NULL element. */
+ size_t count = 0;
+ while (sim_completions[count] != NULL)
+ count++;

- return result;
+ for (size_t i = count; i > 0; i--)
+ {
+ gdb::unique_xmalloc_ptr<char> match (sim_completions[i - 1]);
+ sim_completions[i - 1] = NULL;
+ tracker.add_completion (std::move (match));
+ }
}

/* Check to see if a thread is still alive. */
--
2.5.5