[PATCH] Add -verify option to load command

[Luis Machado <lgustavo@codesourcery.com>]

This is also a leftover bit from flash programming that can also be used by
other targets as needed.  GDB already has some minimal memory verification
functionality.

The following patch adds a new -verify parameter to the load command that
forces GDB to verify all the memory written during the load operation.

This is useful to make sure bare-metal targets have had the program and data
loaded successfully.  I wouldn't say this is too useful for hosted
environments, but not harmful either.

What do you think?

gdb/doc/ChangeLog:

2017-01-05  Mike Wrighton  <mike_wrighton@codesourcery.com>
	    Luis Machado  <lgustavo@codesourcery.com>

	gdb/doc/
	* gdb.texinfo (load): Added verify flag to load command description.

gdb/ChangeLog:

2017-01-05  Mike Wrighton  <mike_wrighton@codesourcery.com>
	    Luis Machado  <lgustavo@codesourcery.com>

	* symfile.c (generic_load): Add -verify arg.
	(_initialize_symfile): Document new -verify option in the load
	command's help text.
	* target-memory.c (target_write_memory_blocks): Add verify parameter
	and handle it.
	* target.h (target_write_memory_blocks): Add verify argument and
	document it.
---
 gdb/doc/gdb.texinfo |  5 ++++-
 gdb/symfile.c       | 35 ++++++++++++++++++++++++-----------
 gdb/target-memory.c | 20 +++++++++++++++++++-
 gdb/target.h        |  5 ++++-
 4 files changed, 51 insertions(+), 14 deletions(-)

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 44ae068..39de23c 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -19592,7 +19592,7 @@ Show the current status of displaying communications between
 @table @code
 
 @kindex load @var{filename}
-@item load @var{filename}
+@item load @var{filename} [-verify]
 @anchor{load}
 Depending on what remote debugging facilities are configured into
 @value{GDBN}, the @code{load} command may be available.  Where it exists, it
@@ -19614,6 +19614,9 @@ specifies a fixed address.
 Depending on the remote side capabilities, @value{GDBN} may be able to
 load programs into flash memory.
 
+The optional @code{-verify} argument enables verification of the data that was
+loaded to the target's memory.
+
 @code{load} does not repeat if you press @key{RET} again after using it.
 @end table
 
diff --git a/gdb/symfile.c b/gdb/symfile.c
index 0af1900..4fdde17 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -2080,6 +2080,8 @@ generic_load (const char *args, int from_tty)
   struct load_section_data cbdata;
   struct load_progress_data total_progress;
   struct ui_out *uiout = current_uiout;
+  int arg_idx;
+  int verify = 0;
 
   CORE_ADDR entry;
   char **argv;
@@ -2099,19 +2101,30 @@ generic_load (const char *args, int from_tty)
   filename = tilde_expand (argv[0]);
   make_cleanup (xfree, filename);
 
-  if (argv[1] != NULL)
+  arg_idx = 1;
+  if (argv[arg_idx] != NULL)
     {
       const char *endptr;
 
-      cbdata.load_offset = strtoulst (argv[1], &endptr, 0);
+      if (strcmp (argv[arg_idx], "-verify") == 0)
+	{
+	  verify = 1;
+	  arg_idx++;
+	}
+
+      if (argv[arg_idx] != NULL)
+	{
+	  cbdata.load_offset = strtoul ((const char *) argv[arg_idx],
+					(char **) &endptr, 0);
 
-      /* If the last word was not a valid number then
-         treat it as a file name with spaces in.  */
-      if (argv[1] == endptr)
-        error (_("Invalid download offset:%s."), argv[1]);
+	  /* If the last word was not a valid number then
+	     treat it as a file name with spaces in.  */
+	  if (argv[arg_idx] == endptr)
+	    error (_("Invalid download offset:%s."), argv[arg_idx]);
 
-      if (argv[2] != NULL)
-	error (_("Too many parameters."));
+	  if (argv[arg_idx + 1] != NULL)
+	    error (_("Too many parameters."));
+	}
     }
 
   /* Open the file for loading.  */
@@ -2140,7 +2153,7 @@ generic_load (const char *args, int from_tty)
   steady_clock::time_point start_time = steady_clock::now ();
 
   if (target_write_memory_blocks (cbdata.requests, flash_discard,
-				  load_progress) != 0)
+				  load_progress, verify) != 0)
     error (_("Load failed"));
 
   steady_clock::time_point end_time = steady_clock::now ();
@@ -3952,8 +3965,8 @@ that lies within the boundaries of this symbol file in memory."),
   c = add_cmd ("load", class_files, load_command, _("\
 Dynamically load FILE into the running program, and record its symbols\n\
 for access from GDB.\n\
-A load offset may also be given.\n\
-Usage: load [FILE] [offset expression]"), &cmdlist);
+A load offset and write verification option may also be given.\n\
+Usage: load [FILE] [-verify] [offset expression]"), &cmdlist);
   set_cmd_completer (c, filename_completer);
 
   add_prefix_cmd ("overlay", class_support, overlay_command,
diff --git a/gdb/target-memory.c b/gdb/target-memory.c
index 1c8faa8..615bab8 100644
--- a/gdb/target-memory.c
+++ b/gdb/target-memory.c
@@ -310,7 +310,8 @@ cleanup_write_requests_vector (void *p)
 int
 target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 			    enum flash_preserve_mode preserve_flash_p,
-			    void (*progress_cb) (ULONGEST, void *))
+			    void (*progress_cb) (ULONGEST, void *),
+			    int verify)
 {
   struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
   VEC(memory_write_request_s) *blocks = VEC_copy (memory_write_request_s,
@@ -433,6 +434,23 @@ target_write_memory_blocks (VEC(memory_write_request_s) *requests,
       target_flash_done ();
     }
 
+
+  /* Do we need to verify if the data was properly written to the target's
+     memory?  */
+  if (verify)
+    {
+      /* Go through all memory regions that GDB wrote to and verify the
+	 contents.  */
+      for (i = 0; VEC_iterate (memory_write_request_s, blocks, i, r); ++i)
+	if (target_verify_memory (r->data, r->begin, r->end - r->begin) <= 0)
+	  error ("Load verification failed for region starting at 0x%x",
+		 (unsigned int) r->begin);
+	else
+	  current_uiout->message ("Verified load, size 0x%x lma 0x%x\n",
+				  (unsigned int) (r->end - r->begin),
+				  (unsigned int) r->begin);
+    }
+
  out:
   do_cleanups (back_to);
 
diff --git a/gdb/target.h b/gdb/target.h
index e239c2c..6fc89d4 100644
--- a/gdb/target.h
+++ b/gdb/target.h
@@ -1497,11 +1497,14 @@ enum flash_preserve_mode
      feedback to user.  It will be called with the baton corresponding
      to the request currently being written.  It may also be called
      with a NULL baton, when preserved flash sectors are being rewritten.
+   VERIFY is non-zero if verification should be performed for the data written
+   to the target's memory and zero if no verification should be performed.
 
    The function returns 0 on success, and error otherwise.  */
 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 				enum flash_preserve_mode preserve_flash_p,
-				void (*progress_cb) (ULONGEST, void *));
+				void (*progress_cb) (ULONGEST, void *),
+				int verify);
 
 /* Print a line about the current target.  */
 
-- 
2.7.4