[PATCHv4 14/14] gdb: 'target ...' commands now expect quoted/escaped filenames

Andrew Burgess
2024-07-04T14:24:11Z

This commit changes the 'target ...' commands that accept a filename
to take a quoted or escaped filename rather than a literal filename.

What this means in practice is that if you are specifying a filename
that contains no white space or quote characters, then nothing should
change, e.g.:

target exec /path/to/some/file

works both before and after this commit.

However, if a user wishes to specify a file containing white space
then either the entire filename needs to be quoted, or the special
white space needs to be escaped. Before this patch a user could
write:

target exec /path/to a file/containing spaces

But after this commit the user would have to choose one of:

target exec "/path/to a file/containing spaces"

or

target exec /path/to\ a\ file/containing\ spaces

Obviously this is a potentially breaking change. The benefit of
making this change is consistency. Commands that take multiple
arguments (one of which is a filename) or in the future, commands that
take filename options, will always need to use quoted/escaped
filenames, so converting all unquoted filename commands to use quoting
or escaping makes the UI more consistent.

Additionally (though this is probably not a common problem), GDB
strips trailing white space from commands that the user enters. As
such it is not possible to reference any file that ends in white space
unless the quoting / escaping style is used. Though I suspect very
few users run into this problem!

The downside obviously is that this is a UI breaking change.
---
gdb/NEWS | 4 ++++
gdb/corelow.c | 23 ++++++++++---------
gdb/doc/gdb.texinfo | 9 ++++++++
gdb/exec.c | 7 ++++--
gdb/testsuite/gdb.base/batch-exit-status.exp | 4 ++--
.../gdb.base/filename-completion.exp | 3 +--
gdb/tracectf.c | 11 +++++----
gdb/tracefile-tfile.c | 16 ++++++-------
8 files changed, 47 insertions(+), 30 deletions(-)

diff --git a/gdb/NEWS b/gdb/NEWS
index 4a830a61cda..9058d62d1fb 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -23,6 +23,10 @@ remove-symbol-file -a ADDRESS
multiple terms, e.g. 'function + 0x1000' (without quotes),
previously only a single term could be given.

+target core
+target exec
+target tfile
+target ctf
compile file
maint print c-tdesc
save gdb-index
diff --git a/gdb/corelow.c b/gdb/corelow.c
index 136f29ea2e8..0f87d565afc 100644
--- a/gdb/corelow.c
+++ b/gdb/corelow.c
@@ -614,7 +614,10 @@ core_target_open (const char *arg, int from_tty)
int flags;

target_preopen (from_tty);
- if (!arg)
+
+ std::string filename = extract_single_filename_arg (arg);
+
+ if (filename.empty ())
{
if (current_program_space->core_bfd ())
error (_("No core file specified. (Use `detach' "
@@ -623,25 +626,23 @@ core_target_open (const char *arg, int from_tty)
error (_("No core file specified."));
}

- gdb::unique_xmalloc_ptr<char> filename (tilde_expand (arg));
- if (strlen (filename.get ()) != 0
- && !IS_ABSOLUTE_PATH (filename.get ()))
- filename = make_unique_xstrdup (gdb_abspath (filename).c_str ());
+ if (!IS_ABSOLUTE_PATH (filename.c_str ()))
+ filename = gdb_abspath (filename);

flags = O_BINARY | O_LARGEFILE;
if (write_files)
flags |= O_RDWR;
else
flags |= O_RDONLY;
- scratch_chan = gdb_open_cloexec (filename.get (), flags, 0).release ();
+ scratch_chan = gdb_open_cloexec (filename.c_str (), flags, 0).release ();
if (scratch_chan < 0)
- perror_with_name (filename.get ());
+ perror_with_name (filename.c_str ());

- gdb_bfd_ref_ptr temp_bfd (gdb_bfd_fopen (filename.get (), gnutarget,
+ gdb_bfd_ref_ptr temp_bfd (gdb_bfd_fopen (filename.c_str (), gnutarget,
write_files ? FOPEN_RUB : FOPEN_RB,
scratch_chan));
if (temp_bfd == NULL)
- perror_with_name (filename.get ());
+ perror_with_name (filename.c_str ());

if (!bfd_check_format (temp_bfd.get (), bfd_core))
{
@@ -650,7 +651,7 @@ core_target_open (const char *arg, int from_tty)
thing, on error it does not free all the storage associated
with the bfd). */
error (_("\"%s\" is not a core dump: %s"),
- filename.get (), bfd_errmsg (bfd_get_error ()));
+ filename.c_str (), bfd_errmsg (bfd_get_error ()));
}

current_program_space->cbfd = std::move (temp_bfd);
@@ -1521,7 +1522,7 @@ void
_initialize_corelow ()
{
add_target (core_target_info, core_target_open,
- deprecated_filename_completer);
+ filename_maybe_quoted_completer);
add_cmd ("core-file-backed-mappings", class_maintenance,
maintenance_print_core_file_backed_mappings,
_("Print core file's file-backed mappings."),
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index e35cf45ec31..d95e13f1342 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -16238,6 +16238,9 @@
Both @var{filename} and @var{dirname} must be on a filesystem accessible to
the host.

+The @var{filename} and @var{dirname} arguments supports escaping and
+quoting, see @ref{Filename Arguments,,Filenames As Command Arguments}.
+
@smallexample
(@value{GDBP}) target ctf ctf.ctf
(@value{GDBP}) tfind
@@ -23159,11 +23162,17 @@
An executable file. @samp{target exec @var{program}} is the same as
@samp{exec-file @var{program}}.

+The @var{program} argument supports escaping and quoting, see
+@ref{Filename Arguments,,Filenames As Command Arguments}.
+
@item target core @var{filename}
@cindex core dump file target
A core dump file. @samp{target core @var{filename}} is the same as
@samp{core-file @var{filename}}.

+The @var{filename} argument supports escaping and quoting, see
+@ref{Filename Arguments,,Filenames As Command Arguments}.
+
@item target remote @var{medium}
@cindex remote target
A remote system connected to @value{GDBN} via a serial line or network
diff --git a/gdb/exec.c b/gdb/exec.c
index acd9b04337b..cae08868f8e 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -143,7 +143,10 @@ static void
exec_target_open (const char *args, int from_tty)
{
target_preopen (from_tty);
- exec_file_attach (args, from_tty);
+
+ std::string filename = extract_single_filename_arg (args);
+ exec_file_attach (filename.empty () ? nullptr : filename.c_str (),
+ from_tty);
}

/* This is the target_close implementation. Clears all target
@@ -1120,5 +1123,5 @@ will be loaded as well."),
&setlist, &showlist);

add_target (exec_target_info, exec_target_open,
- deprecated_filename_completer);
+ filename_maybe_quoted_completer);
}
diff --git a/gdb/testsuite/gdb.base/batch-exit-status.exp b/gdb/testsuite/gdb.base/batch-exit-status.exp
index 3721fd56018..51514640958 100644
--- a/gdb/testsuite/gdb.base/batch-exit-status.exp
+++ b/gdb/testsuite/gdb.base/batch-exit-status.exp
@@ -92,5 +92,5 @@ test_exit_status 1 "-batch -x $good_commands -ex \"set not-a-thing 4\"" \
set test "No such file or directory"
set no_such_re ": $test\\."
test_exit_status 1 "-batch \"\"" "1x: $test" ^[multi_line $no_such_re ""]$
-test_exit_status 1 "-batch \"\" \"\"" "2x: $test" \
- ^[multi_line $no_such_re $no_such_re ""]$
+test_exit_status 1 "-batch \"\" \"\"" "$test and No core file specified" \
+ ^[multi_line $no_such_re "No core file specified\\." ""]$
diff --git a/gdb/testsuite/gdb.base/filename-completion.exp b/gdb/testsuite/gdb.base/filename-completion.exp
index 7ba055b9ae7..95a9fbaa857 100644
--- a/gdb/testsuite/gdb.base/filename-completion.exp
+++ b/gdb/testsuite/gdb.base/filename-completion.exp
@@ -301,8 +301,7 @@ proc run_unquoted_tests_core { root cmd { prefix "" } } {
proc run_unquoted_tests { root } {
# Test all the commands which allow quoting of filenames, and
# which require whitespace to be escaped in unquoted filenames.
- foreach_with_prefix cmd { "set logging file" \
- "target core" "add-auto-load-safe-path" } {
+ foreach_with_prefix cmd { "set logging file" "add-auto-load-safe-path" } {
run_unquoted_tests_core $root $cmd
}

diff --git a/gdb/tracectf.c b/gdb/tracectf.c
index 25a8fe7ead9..b4997f8589f 100644
--- a/gdb/tracectf.c
+++ b/gdb/tracectf.c
@@ -1111,7 +1111,7 @@ ctf_read_tp (struct uploaded_tp **uploaded_tps)
second packet which contains events on trace blocks. */

static void
-ctf_target_open (const char *dirname, int from_tty)
+ctf_target_open (const char *args, int from_tty)
{
struct bt_ctf_event *event;
uint32_t event_id;
@@ -1119,10 +1119,11 @@ ctf_target_open (const char *dirname, int from_tty)
struct uploaded_tsv *uploaded_tsvs = NULL;
struct uploaded_tp *uploaded_tps = NULL;

- if (!dirname)
+ std::string dirname = extract_single_filename_arg (args);
+ if (dirname.empty ())
error (_("No CTF directory specified."));

- ctf_open_dir (dirname);
+ ctf_open_dir (dirname.c_str ());

target_preopen (from_tty);

@@ -1162,7 +1163,7 @@ ctf_target_open (const char *dirname, int from_tty)
start_pos = bt_iter_get_pos (bt_ctf_get_iter (ctf_iter));
gdb_assert (start_pos->type == BT_SEEK_RESTORE);

- trace_dirname = make_unique_xstrdup (dirname);
+ trace_dirname = make_unique_xstrdup (dirname.c_str ());
current_inferior ()->push_target (&ctf_ops);

inferior_appeared (current_inferior (), CTF_PID);
@@ -1722,6 +1723,6 @@ _initialize_ctf ()
{
#if HAVE_LIBBABELTRACE
add_target (ctf_target_info, ctf_target_open,
- deprecated_filename_completer);
+ filename_maybe_quoted_completer);
#endif
}
diff --git a/gdb/tracefile-tfile.c b/gdb/tracefile-tfile.c
index 66769216a6b..b59b5c73325 100644
--- a/gdb/tracefile-tfile.c
+++ b/gdb/tracefile-tfile.c
@@ -462,24 +462,24 @@ tfile_target_open (const char *arg, int from_tty)
struct uploaded_tsv *uploaded_tsvs = NULL;

target_preopen (from_tty);
- if (!arg)
+ std::string filename = extract_single_filename_arg (arg);
+ if (filename.empty ())
error (_("No trace file specified."));

- gdb::unique_xmalloc_ptr<char> filename (tilde_expand (arg));
- if (!IS_ABSOLUTE_PATH (filename.get ()))
- filename = make_unique_xstrdup (gdb_abspath (filename).c_str ());
+ if (!IS_ABSOLUTE_PATH (filename.c_str ()))
+ filename = gdb_abspath (filename);

flags = O_BINARY | O_LARGEFILE;
flags |= O_RDONLY;
- scratch_chan = gdb_open_cloexec (filename.get (), flags, 0).release ();
+ scratch_chan = gdb_open_cloexec (filename.c_str (), flags, 0).release ();
if (scratch_chan < 0)
- perror_with_name (filename.get ());
+ perror_with_name (filename.c_str ());

/* Looks semi-reasonable. Toss the old trace file and work on the new. */

current_inferior ()->unpush_target (&tfile_ops);

- trace_filename = std::move (filename);
+ trace_filename = make_unique_xstrdup (filename.c_str ());
trace_fd = scratch_chan;

/* Make sure this is clear. */
@@ -1121,5 +1121,5 @@ void
_initialize_tracefile_tfile ()
{
add_target (tfile_target_info, tfile_target_open,
- deprecated_filename_completer);
+ filename_maybe_quoted_completer);
}
--
2.25.4