[PATCH] python/19506 -- gdb.Breakpoint address location regression

[Keith Seitz <keiths@redhat.com>]

When the locations API was committed, it assumed that all valid
arguments to the gdb.Breakpoint command were a linespec (aside from
keywords describing various breakpoint properties).  However, address
locations are a separate class of locations which were overlooked by my
patch.

This patch introduces a new function analogous to the CLI function
string_to_event_location.  This new function only handles address and
linespec locations.  I have made no attempt to fully implement explicit
locations.

This patch fixes python/19506:

(gdb) python gdb.Breakpoint("*main")
Traceback (most recent call last):
  File "<string>", line 1, in <module>
RuntimeError: Function "*main" not defined.
Error while executing Python code.

Now:

(gdb) python gdb.Breakpoint("*main")
Breakpoint 1 at 0x4005fb: file ../../../src/gdb/testsuite/gdb.python/py-breakpoint.c, line 32.

gdb/ChangeLog

	* python/py-breakpoint.c (python_string_to_event_location): New
	function.
	(bppy_init): Use python_string_to_event_location instead of
	new_linespec_location.

gdb/testsuite/gdb.python

	* gdb.python/py-breakpoint.exp (test_bkpt_address): New proc.
	(toplevel): Call test_bkpt_address.
---
 gdb/python/py-breakpoint.c                 | 35 +++++++++++++++++++++++++++++-
 gdb/testsuite/gdb.python/py-breakpoint.exp | 31 ++++++++++++++++++++++++++
 2 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c
index 85b17d5..588b41f 100644
--- a/gdb/python/py-breakpoint.c
+++ b/gdb/python/py-breakpoint.c
@@ -31,6 +31,7 @@
 #include "arch-utils.h"
 #include "language.h"
 #include "location.h"
+#include "linespec.h"
 
 /* Number of live breakpoints.  */
 static int bppy_live;
@@ -624,6 +625,38 @@ bppy_get_ignore_count (PyObject *self, void *closure)
   return PyInt_FromLong (self_bp->bp->ignore_count);
 }
 
+/* Attempt to convert the string in *STRINGP to an event_location.
+   STRINGP is advanced past any processed input.  Returns an event_location
+   (malloc'd).
+
+   The return result must be freed with delete_event_location.  */
+
+static struct event_location *
+python_string_to_event_location (char **stringp)
+{
+  struct event_location *location;
+
+  /* First check if the string represents a address location.  */
+  if (*stringp != NULL && **stringp == '*')
+    {
+      const char *arg, *orig;
+      CORE_ADDR addr;
+
+      orig = arg = *stringp;
+      addr = linespec_expression_to_pc (&arg);
+      location = new_address_location (addr, orig, arg - orig);
+      *stringp += arg - orig;
+    }
+  else
+    {
+      /* Explicit locations are not yet implemented, so everything else
+	 must be a linespec location.  */
+      location = new_linespec_location (stringp);
+    }
+
+  return location;
+}
+
 /* Python function to create a new breakpoint.  */
 static int
 bppy_init (PyObject *self, PyObject *args, PyObject *kwargs)
@@ -672,7 +705,7 @@ bppy_init (PyObject *self, PyObject *args, PyObject *kwargs)
 	  {
 	    struct event_location *location;
 
-	    location = new_linespec_location (&copy);
+	    location = python_string_to_event_location (&copy);
 	    make_cleanup_delete_event_location (location);
 	    create_breakpoint (python_gdbarch,
 			       location, NULL, -1, NULL,
diff --git a/gdb/testsuite/gdb.python/py-breakpoint.exp b/gdb/testsuite/gdb.python/py-breakpoint.exp
index af6c5fc..fe535c9 100644
--- a/gdb/testsuite/gdb.python/py-breakpoint.exp
+++ b/gdb/testsuite/gdb.python/py-breakpoint.exp
@@ -462,6 +462,36 @@ proc test_bkpt_temporary { } {
     }
 }
 
+# Test address locations.
+
+proc test_bkpt_address {} {
+    global gdb_prompt decimal srcfile
+
+    # Delete all breakpoints
+    delete_breakpoints
+
+    gdb_test "python gdb.Breakpoint(\"*main\")" \
+	".*Breakpoint ($decimal)+ at .*$srcfile, line ($decimal)+\."
+
+    gdb_py_test_silent_cmd \
+	"python main_loc = gdb.parse_and_eval(\"main\").address" \
+	"eval address of main" 0
+
+    # Python 2 vs 3 ... Check `int' first. If that fails, try `long'.
+    gdb_test_multiple "python main_addr = int(main_loc)" "int value of main" {
+	-re "Traceback.*$gdb_prompt $" {
+	    gdb_test_no_output "python main_addr = long(main_loc)" \
+		"long value of main"
+	}
+	-re "$gdb_prompt $" {
+	    pass "int value of main"
+	}
+    }
+
+    gdb_test "python gdb.Breakpoint(\"*{}\".format(str(main_addr)))" \
+	".*Breakpoint ($decimal)+ at .*$srcfile, line ($decimal)+\."
+}
+
 test_bkpt_basic
 test_bkpt_deletion
 test_bkpt_cond_and_cmds
@@ -470,3 +500,4 @@ test_watchpoints
 test_bkpt_internal
 test_bkpt_eval_funcs
 test_bkpt_temporary
+test_bkpt_address
-- 
2.1.0