RE: [PATCH] new MI command for pattern filling of memory regions

Giuseppe MONTALTO
2012-05-25T14:35:56Z

I reworked the patch, including the test script;
Accordingly with your feedback, the sscanf cycle is now performed only once.

Here's the new patch, please let me know if there is anything more to change.

Regards,
Giuseppe

gdb/ChangeLog | 5 ++
gdb/mi/mi-main.c | 50 +++++++++++++++++----
gdb/testsuite/ChangeLog | 4 ++
gdb/testsuite/gdb.mi/mi-fill-memory.exp | 72 +++++++++++++++++++++++++++++++
4 files changed, 122 insertions(+), 9 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 309473e..9ec8882 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2012-05-09 Giuseppe Montalto <giuseppe.montalto@st.com>
+
+ * mi/mi-main.c (mi_cmd_data_write_memory): additional
+ parameter for pattern filling of memory regions
+
2012-05-09 Pedro Alves <palves@redhat.com>

* target.c (set_maintenance_target_async_permitted): Rename to ...
diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
index 90fb624..7315848 100644
--- a/gdb/mi/mi-main.c
+++ b/gdb/mi/mi-main.c
@@ -1658,7 +1658,8 @@ mi_cmd_data_write_memory (char *command, char **argv, int argc)
/* Implementation of the -data-write-memory-bytes command.

ADDR: start address
- DATA: string of bytes to write at that address. */
+ DATA: string of bytes to write at that address
+ COUNT: number of bytes to be filled (decimal integer). */

void
mi_cmd_data_write_memory_bytes (char *command, char **argv, int argc)
@@ -1666,27 +1667,58 @@ mi_cmd_data_write_memory_bytes (char *command, char **argv, int argc)
CORE_ADDR addr;
char *cdata;
gdb_byte *data;
- int len, r, i;
+ gdb_byte *databuf;
+ int len, r, i, steps, reminder;
+ long int count, j;
struct cleanup *back_to;

- if (argc != 2)
- error (_("Usage: ADDR DATA."));
+ if (argc != 2 && argc != 3)
+ error (_("Usage: ADDR DATA [COUNT]."));

addr = parse_and_eval_address (argv[0]);
cdata = argv[1];
- len = strlen (cdata)/2;
+ len = strlen (cdata) / 2;
+ if (argc == 3)
+ count = strtol(argv[2], NULL, 10);
+ else
+ count = len;

- data = xmalloc (len);
- back_to = make_cleanup (xfree, data);
+ databuf = xmalloc (len * sizeof(gdb_byte));

for (i = 0; i < len; ++i)
{
int x;
sscanf (cdata + i * 2, "%02x", &x);
- data[i] = (gdb_byte) x;
+ databuf[i] = (gdb_byte)x;
}

- r = target_write_memory (addr, data, len);
+ if (len < count)
+ {
+ /* pattern is made of less bytes than count:
+ repeat pattern to fill memory. */
+ data = xmalloc (count);
+ back_to = make_cleanup (xfree, data);
+
+ steps = count / len;
+ reminder = count % len; /* there may be some spare bytes. */
+ for (j = 0; j < steps; j++)
+ memcpy (data + j * len, databuf, (size_t) len);
+
+ if (reminder > 0) /* copy spare bytes too. */
+ memcpy (data + steps * len, databuf, (size_t) reminder);
+ }
+ else
+ {
+ /* pattern is longer than (or equal to) count:
+ just copy len bytes. */
+ data = xmalloc (len);
+ back_to = make_cleanup (xfree, data);
+ memcpy (data, databuf, (size_t) len);
+ }
+
+ xfree(databuf);
+
+ r = target_write_memory (addr, data, count);
if (r != 0)
error (_("Could not write memory"));

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 43549bf..a49274f 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2012-05-09 Giuseppe Montalto <giuseppe.montalto@st.com>
+
+ * gdb.mi/mi-fill-memory.exp: New test.
+
2012-05-08 Maciej W. Rozycki <macro@codesourcery.com>

* gdb.mi/mi-var-display.exp: Check for the existence of $fp
diff --git a/gdb/testsuite/gdb.mi/mi-fill-memory.exp b/gdb/testsuite/gdb.mi/mi-fill-memory.exp
new file mode 100644
index 0000000..b6961b1
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/mi-fill-memory.exp
@@ -0,0 +1,72 @@
+# Copyright (C) 2012 Free Software Foundation, Inc.
+# Copyright (C) 2012 STMicroelectronics
+
+# 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/>.
+
+#
+# test basic Machine interface (MI) operations
+#
+# Verify that, using the MI, we can load a program and do
+# other basic things that are used by all test files through mi_gdb_exit,
+# mi_gdb_start, mi_delete_breakpoints, mi_gdb_reinitialize_dir and
+# mi_gdb_load, so we can safely use those.
+#
+# The goal is not to test gdb functionality, which is done by other tests,
+# but the command syntax and correct output response to MI operations.
+#
+# added for testing the -data-write-memory-bytes MI command enhancements
+#
+
+load_lib mi-support.exp
+set MIFLAGS "-i=mi"
+
+gdb_exit
+if [mi_gdb_start] {
+ continue
+}
+
+set testfile "mi-read-memory"
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug additional_flags=-DFAKEARGV}] != "" } {
+ untested mi-read-memory.exp
+ return -1
+}
+
+
+mi_run_to_main
+mi_next_to "main" "" "mi-read-memory.c" "20" "next at main"
+
+mi_gdb_test "1-data-write-memory-bytes"\
+ "1\\\^error,msg=\"Usage: ADDR DATA \\\[COUNT\\\]\.\""\
+ "no arguments"
+
+mi_gdb_test "2-data-write-memory-bytes 8"\
+ "2\\\^error,msg=\"Usage: ADDR DATA \\\[COUNT\\\]\.\""\
+ "one argument missing"
+
+mi_gdb_test "3-data-write-memory-bytes \$pc ab"\
+ "3\\\^done" \
+ "memory successfully written"
+
+mi_gdb_test "4-data-write-memory-bytes \$pc ab 8"\
+ "4\\\^done" \
+ "memory successfully filled (8 bytes)"
+
+mi_gdb_test "5-interpreter-exec console \"x \$pc\"" \
+ ".*0xabababab.*" \
+ "pattern correctly read from memory"
+
+mi_gdb_exit
+return 0

> -----Original Message-----
> From: Giuseppe MONTALTO
> Sent: Friday, May 11, 2012 6:06 PM
> To: 'Tom Tromey'
> Cc: gdb-patches@sourceware.org
> Subject: RE: [PATCH] new MI command for pattern filling of memory
> regions
>
> Thanks,
>
> my answers are interleaved below.
>
> > -----Original Message-----
> > From: Tom Tromey [mailto:tromey@redhat.com]
> > Sent: Friday, May 11, 2012 4:14 PM
> > To: Giuseppe MONTALTO
> > Cc: gdb-patches@sourceware.org
> > Subject: Re: [PATCH] new MI command for pattern filling of memory
> > regions
> >
> > The indentation is wrong here and elsewhere in the patch.
> > There are missing spaces as well.
> > See the GNU Coding Standards for details.
>
> I'll try to better format the code.
>
> >
> > I don't think the cast here, or other casts in the patch, are
> > necessary.
>
> Consider them gone.
>
> >
> > Giuseppe> + /* pattern is made of less bytes than count:
> > Giuseppe> + repeat pattern to fill memory. */
> > Giuseppe> + data = xmalloc (count/len);
> >
> > This allocates count/len bytes...
> >
> > Giuseppe> + steps = count/len;
> > Giuseppe> + for (j = 0; j < steps; j++)
> > Giuseppe> + {
> > Giuseppe> + for (i = 0; i < len; ++i)
> > Giuseppe> + {
> > Giuseppe> + int x;
> > Giuseppe> + sscanf (cdata + i * 2, "%02x", &x);
> > Giuseppe> + data[i + j * len] = (gdb_byte)x;
> >
> > ... but writes 'count' bytes.
>
> you're right; I was supposed to allocate 'count' bytes.
>
> Incidentally, there's a worse error there:
> is that I'm counting the cycles basing on the result of an integer
> division, hence not taking into account the spare bytes!
>
> I'll fix that too...
>
> Giuseppe