[PATCH] [1/2] Add new 'z' format for print command

[Andrew Burgess]

The MI code for displaying registers currently supports
a special case 'r' format that displays the register in
'raw' form, this is hexadecimal, zero padded to the size
of the register.

Having this as a special case in the MI code causes problems
with optimized out registers, which I tried addressing in a
patch here:
  http://sourceware.org/ml/gdb-patches/2013-07/msg00193.html

Pedro pointed out that I could do better, so, this patch
introduces a new 'z' format within the core value printing
code that displays scalars using zero padded hexadecimal.
I've mentioned this in the docs and added a test for the
new format.

In patch [2/2] I'll change the MI code to make use of this
new 'z' formatter.

OK to apply?

Thanks,
Andrew



gdb/ChangeLog

2013-07-08  Andrew Burgess  <aburgess@broadcom.com>

	* printcmd.c (print_scalar_formatted): Add new 'z' formatter.

gdb/docs/ChangeLog

2013-07-08  Andrew Burgess  <aburgess@broadcom.com>

	* gdb.texinfo (Output Formats): Mention the new 'z' formatter.

gdb/testsuite/ChangeLog

2013-07-08  Andrew Burgess  <aburgess@broadcom.com>

	* gdb.base/printcmds.exp (test_print_int_arrays): Add tests for x,
	z, o, and t output formats.
	* gdb.base/display.exp: Use 'k' as an undefined format now that
	'z' is defined.

 
diff --git a/gdb/printcmd.c b/gdb/printcmd.c
index 99d4dba..f34d18b 100644
--- a/gdb/printcmd.c
+++ b/gdb/printcmd.c
@@ -533,6 +533,10 @@ print_scalar_formatted (const void *valaddr, struct type *type,
       }
       break;
 
+    case 'z':
+      print_hex_chars (stream, valaddr, len, byte_order);
+      break;
+
     default:
       error (_("Undefined output format \"%c\"."), options->format);
     }
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index fae54e4..c5d7754 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -8517,6 +8517,11 @@ Without this format, @value{GDBN} displays pointers to and arrays of
 strings.  Single-byte members of a vector are displayed as an integer
 array.
 
+@item z
+Like @samp{x} formatting, the integer is printed as hexadecimal, but
+leading zeros are printed to pad the value to the size of the integer
+type.
+
 @item r
 @cindex raw printing
 Print using the @samp{raw} formatting.  By default, @value{GDBN} will
diff --git a/gdb/testsuite/gdb.base/display.exp b/gdb/testsuite/gdb.base/display.exp
index 5db84cc..9a0b1dd 100644
--- a/gdb/testsuite/gdb.base/display.exp
+++ b/gdb/testsuite/gdb.base/display.exp
@@ -168,7 +168,7 @@ gdb_test "printf \"%p\\n\", 1" "0x1"
 
 # play with "print", too
 #
-gdb_test "print/z j" ".*Undefined output format.*"
+gdb_test "print/k j" ".*Undefined output format.*"
 gdb_test "print/d j" " = 0\[\\r\\n\]+"   "debug test output 1"
 gdb_test "print/r j" " = 0\[\\r\\n\]+"   "debug test output 1a"
 gdb_test "print/x j" " = 0x0\[\\r\\n\]+" "debug test output 2"
diff --git a/gdb/testsuite/gdb.base/printcmds.exp b/gdb/testsuite/gdb.base/printcmds.exp
index 0597ab0..4883fd5 100644
--- a/gdb/testsuite/gdb.base/printcmds.exp
+++ b/gdb/testsuite/gdb.base/printcmds.exp
@@ -587,6 +587,16 @@ proc test_print_int_arrays {} {
 	" = {{{0, 1}, {2, 3}, {4, 5}}, {{6, 7}, {8, 9}, {10, 11}}}"
     gdb_test_escape_braces "p int4dim" \
 	" = {{{{0, 1}, {2, 3}, {4, 5}}, {{6, 7}, {8, 9}, {10, 11}}}}"
+
+    # Some checks for various output formats.
+    gdb_test_escape_braces "p/x int4dim" \
+	" = {{{{0x0, 0x1}, {0x2, 0x3}, {0x4, 0x5}}, {{0x6, 0x7}, {0x8, 0x9}, {0xa, 0xb}}}}"
+    gdb_test_escape_braces "p/z int4dim" \
+       " = {{{{0x0+0, 0x0+1}, {0x0+2, 0x0+3}, {0x0+4, 0x0+5}}, {{0x0+6, 0x0+7}, {0x0+8, 0x0+9}, {0x0+a, 0x0+b}}}}"
+    gdb_test_escape_braces "p/o int4dim" \
+       " = {{{{0, 01}, {02, 03}, {04, 05}}, {{06, 07}, {010, 011}, {012, 013}}}}"
+    gdb_test_escape_braces "p/t int4dim" \
+       " = {{{{0, 1}, {10, 11}, {100, 101}}, {{110, 111}, {1000, 1001}, {1010, 1011}}}}"
 }
 
 proc test_print_typedef_arrays {} {