gdb/python: new gdb.architecture_names function

Add a new function to the Python API, gdb.architecture_names().  This
function returns a list containing all of the supported architecture
names within the current build of GDB.

The values returned in this list are all of the possible values that
can be returned from gdb.Architecture.name().

gdb/NEWS

@@ -45,6 +45,10 @@ maint show internal-warning backtrace
      event is triggered once GDB decides it is going to exit, but
      before GDB starts to clean up its internal state.
 
+  ** New function gdb.architecture_names(), which returns a list
+     containing all of the possible Architecture.name() values.  Each
+     entry is a string.
+
 *** Changes in GDB 11
 
 * The 'set disassembler-options' command now supports specifying options

gdb/doc/python.texi

@@ -557,6 +557,14 @@ such as those used by readline for command input, and annotation
 related prompts are prohibited from being changed.
 @end defun
 
+@defun gdb.architecture_names ()
+Return a list containing all of the architecture names that the
+current build of @value{GDBN} supports.  Each architecture name is a
+string.  The names returned in this list are the same names as are
+returned from @code{gdb.Architecture.name}
+(@pxref{gdbpy_architecture_name,,Architecture.name}).
+@end defun
+
 @node Exception Handling
 @subsubsection Exception Handling
 @cindex python exceptions
@@ -5834,6 +5842,7 @@ by an instance of the @code{gdb.Architecture} class.
 
 A @code{gdb.Architecture} class has the following methods:
 
+@anchor{gdbpy_architecture_name}
 @defun Architecture.name ()
 Return the name (string value) of the architecture.
 @end defun

gdb/python/py-arch.c

@@ -271,6 +271,29 @@ archpy_register_groups (PyObject *self, PyObject *args)
   return gdbpy_new_reggroup_iterator (gdbarch);
 }
 
+/* Implementation of gdb.architecture_names().  Return a list of all the
+   BFD architecture names that GDB understands.  */
+
+PyObject *
+gdbpy_all_architecture_names (PyObject *self, PyObject *args)
+{
+  gdbpy_ref<> list (PyList_New (0));
+  if (list == nullptr)
+    return nullptr;
+
+  std::vector<const char *> name_list = gdbarch_printable_names ();
+  for (const char *name : name_list)
+    {
+      gdbpy_ref <> py_name (PyString_FromString (name));
+      if (py_name == nullptr)
+	return nullptr;
+      if (PyList_Append (list.get (), py_name.get ()) < 0)
+	return nullptr;
+    }
+
+ return list.release ();
+}
+
 void _initialize_py_arch ();
 void
 _initialize_py_arch ()

gdb/python/python-internal.h

@@ -469,6 +469,7 @@ PyObject *objfpy_get_xmethods (PyObject *, void *);
 PyObject *gdbpy_lookup_objfile (PyObject *self, PyObject *args, PyObject *kw);
 
 PyObject *gdbarch_to_arch_object (struct gdbarch *gdbarch);
+PyObject *gdbpy_all_architecture_names (PyObject *self, PyObject *args);
 
 PyObject *gdbpy_new_register_descriptor_iterator (struct gdbarch *gdbarch,
 						  const char *group_name);

gdb/python/python.c

@@ -2324,6 +2324,10 @@ Set the value of the convenience variable $NAME." },
 Register a TUI window constructor." },
 #endif	/* TUI */
 
+  { "architecture_names", gdbpy_all_architecture_names, METH_NOARGS,
+    "architecture_names () -> List.\n\
+Return a list of all the architecture names GDB understands." },
+
   {NULL, NULL, 0, NULL}
 };
 

gdb/testsuite/gdb.python/py-arch.exp

@@ -62,3 +62,54 @@ if { ![is_address_zero_readable] } {
     gdb_test "python arch.disassemble(0, 0)" ".*gdb\.MemoryError.*" \
 	"test bad memory access"
 }
+
+# Test for gdb.architecture_names().  First we're going to grab the
+# complete list of architecture names using the 'complete' command.
+set arch_names []
+gdb_test_no_output "set max-completions unlimited"
+gdb_test_multiple "complete set architecture " "" {
+    -re "complete set architecture\[^\r\n\]+\r\n" {
+	exp_continue
+    }
+    -re "^set architecture \(\[^\r\n\]+\)\r\n" {
+	set arch $expect_out(1,string)
+	if { "$arch" != "auto" } {
+	    set arch_names [lappend arch_names $arch]
+	}
+	exp_continue
+    }
+    -re "^$gdb_prompt $" {
+	gdb_assert { [llength $arch_names] > 0 }
+    }
+}
+
+# Now find all of the architecture names using Python.
+set py_arch_names []
+gdb_test_no_output "python all_arch = gdb.architecture_names()"
+gdb_test_no_output "python all_arch.sort()"
+gdb_test_multiple "python print(\"\\n\".join((\"Arch: %s\" % a) for a in all_arch))" "" {
+    -re "python \[^\r\n\]+\r\n" {
+	exp_continue
+    }
+    -re "^Arch: \(\[^\r\n\]+\)\r\n" {
+	set arch $expect_out(1,string)
+	set py_arch_names [lappend py_arch_names $arch]
+	exp_continue
+    }
+    -re "$gdb_prompt $" {
+	gdb_assert { [llength $py_arch_names] > 0 }
+    }
+}
+
+# Check the two lists of architecture names are the same length, and
+# that the list contents all match.
+gdb_assert { [llength $arch_names] == [llength $py_arch_names] }
+set lists_match true
+foreach a $arch_names b $py_arch_names {
+    if { $a != $b } {
+	set lists_match false
+	verbose -log "Mismatch is architecture list '$a' != '$b'"
+	break
+    }
+}
+gdb_assert { $lists_match }