Some improvements to configuration

- Modify `get_set_string()` to match GDB's builtin behaviour
- Make `gcc-compiler-path`'s and `cymbol-editor`'s `set_show_doc` first strings to lowercase
- Change `gcc-compiler-path` and `cymbol-editor` to `gdb.PARAM_OPTIONAL_FILENAME`
- Add resolve_heap_via_heuristic as a gdb.PARAM_ENUM config with options:
  - auto: pwndbg will try to use heuristics if debug symbols are missing
  - force: pwndbg will always try to use heuristics, even if debug symbols are available
  - never: pwndbg will never use heuristics to resolve the heap
- Move some hints to `resolve_heap_via_heuristic`'s `help_docstring`

pwndbg/commands/cymbol.py

@@ -34,11 +34,15 @@ from pwndbg.color import message
 gcc_compiler_path = pwndbg.gdblib.config.add_param(
     "gcc-compiler-path",
     "",
-    "Path to the gcc/g++ toolchain for generating imported symbols",
+    "path to the gcc/g++ toolchain for generating imported symbols",
+    param_class=gdb.PARAM_OPTIONAL_FILENAME,
 )
 
 cymbol_editor = pwndbg.gdblib.config.add_param(
-    "cymbol-editor", "", "Path to the editor for editing custom structures"
+    "cymbol-editor",
+    "",
+    "path to the editor for editing custom structures",
+    param_class=gdb.PARAM_OPTIONAL_FILENAME,
 )
 
 # Remeber loaded symbols. This would be useful for 'remove-symbol-file'.

pwndbg/commands/heap.py

@@ -1179,7 +1179,7 @@ parser.add_argument(
 
 @pwndbg.commands.ArgparsedCommand(parser)
 def heap_config(filter_pattern):
-    display_config(filter_pattern, "heap")
+    display_config(filter_pattern, "heap", has_file_command=False)
 
     print(
         message.hint(

pwndbg/gdblib/config.py

@@ -29,9 +29,9 @@ class Parameter(gdb.Parameter):
         # `set_doc`, `show_doc`, and `__doc__` must be set before `gdb.Parameter.__init__`.
         # They will be used for `help set <param>` and `help show <param>`,
         # respectively
-        self.set_doc = "Set " + param.set_show_doc
-        self.show_doc = "Show " + param.set_show_doc
-        self.__doc__ = param.help_docstring
+        self.set_doc = "Set " + param.set_show_doc + "."
+        self.show_doc = "Show " + param.set_show_doc + "."
+        self.__doc__ = param.help_docstring or None
 
         if param.param_class == gdb.PARAM_ENUM:
             super().__init__(
@@ -76,13 +76,13 @@ class Parameter(gdb.Parameter):
         if not pwndbg.decorators.first_prompt:
             return ""
 
-        return "Set %s to %r" % (self.param.set_show_doc, self.native_value)
+        return "Set %s to %r." % (self.param.set_show_doc, self.native_value)
 
     def get_show_string(self, svalue):
         """Handles the GDB `show <param>` command"""
-        return "The current value of %r is %r" % (
-            self.param.name,
-            Parameter._value_to_gdb_native(svalue, self.param.param_class),
+        return "%s is %r." % (
+            self.param.set_show_doc.capitalize(),
+            svalue,
         )
 
     @staticmethod

pwndbg/heap/__init__.py

@@ -1,3 +1,5 @@
+import gdb
+
 import pwndbg.color.message as message
 import pwndbg.gdblib.config
 import pwndbg.gdblib.symbol
@@ -7,7 +9,7 @@ current = None
 
 
 def add_heap_param(
-    name, default, set_show_doc, *, help_docstring=None, param_class=None, enum_sequence=None
+    name, default, set_show_doc, *, help_docstring="", param_class=None, enum_sequence=None
 ):
     return pwndbg.gdblib.config.add_param(
         name,
@@ -35,7 +37,36 @@ symbol_list = [main_arena, thread_arena, mp_, tcache, global_max_fast]
 heap_chain_limit = add_heap_param("heap-dereference-limit", 8, "number of bins to dereference")
 
 resolve_heap_via_heuristic = add_heap_param(
-    "resolve-heap-via-heuristic", False, "Resolve missing heap related symbols via heuristics"
+    "resolve-heap-via-heuristic",
+    "auto",
+    "the strategy to resolve heap via heuristic",
+    help_docstring="""If pwndbg fails to use the debug symbols to resolve the heap, it can try to resolve the heap via heuristics.
+This configuration sets the strategy for resolving the heap.
+
+There are three strategies:
+auto    == pwndbg will try to use heuristics if debug symbols are missing
+force   == pwndbg will always try to use heuristics, even if debug symbols are available
+never   == pwndbg will never use heuristics to resolve the heap
+
+
+If the output of the heap related command produces errors with heuristics, you can try manually setting the libc symbol addresses.
+For this, see the `heap_config` command output and set the `main_arena`, `mp_`, `global_max_fast`, `tcache` and `thread_arena` addresses.
+
+Note: pwndbg will generate more reliable results with proper debug symbols.
+Therefore, when debug symbols are missing, you should try to install them first if you haven't already.
+
+They can probably be installed via the package manager of your choice.
+See also: https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html
+
+E.g. on Ubuntu/Debian you might need to do the following steps (for 64-bit and 32-bit binaries):
+sudo apt-get install libc6-dbg
+sudo dpkg --add-architecture i386
+sudo apt-get install libc-dbg:i386
+
+If you used setup.sh on Arch based distro you'll need to do a power cycle or set environment variable manually like this: export DEBUGINFOD_URLS=https://debuginfod.archlinux.org
+""",
+    param_class=gdb.PARAM_ENUM,
+    enum_sequence=["auto", "force", "never"],
 )
 
 
@@ -59,7 +90,7 @@ def resolve_heap(is_first_run=False):
     import pwndbg.heap.ptmalloc
 
     global current
-    if resolve_heap_via_heuristic:
+    if resolve_heap_via_heuristic == "force":
         current = pwndbg.heap.ptmalloc.HeuristicHeap()
         if not is_first_run and pwndbg.gdblib.proc.alive and current.libc_has_debug_syms():
             print(
@@ -68,11 +99,5 @@ def resolve_heap(is_first_run=False):
                     " This is not recommended!"
                 )
             )
-        else:
-            print(
-                message.warn(
-                    "You are going to resolve the heap via heuristic. This might not work in all cases."
-                )
-            )
     else:
         current = pwndbg.heap.ptmalloc.DebugSymsHeap()

pwndbg/lib/config.py

@@ -26,13 +26,18 @@ class Parameter:
         default,
         set_show_doc,
         *,
-        help_docstring=None,
+        help_docstring="",
         param_class=None,
         enum_sequence=None,
         scope="config",
     ):
+        # Note: `set_show_doc` should be a noun phrase, e.g. "the value of the foo"
+        # The `set_doc` will be "Set the value of the foo."
+        # The `show_doc` will be "Show the value of the foo."
+        # `get_set_string()` will return "Set the value of the foo to VALUE."
+        # `get_show_string()` will return "Show the value of the foo."
         self.set_show_doc = set_show_doc.strip()
-        self.help_docstring = help_docstring.strip() if help_docstring else None
+        self.help_docstring = help_docstring.strip()
         self.name = name
         self.default = default
         self.value = default
@@ -129,7 +134,7 @@ class Config:
         default,
         set_show_doc,
         *,
-        help_docstring=None,
+        help_docstring="",
         param_class=None,
         enum_sequence=None,
         scope="config",

tests/gdb-tests/tests/heap/test_heap.py

@@ -123,7 +123,7 @@ def test_malloc_chunk_command(start_binary):
 
 def test_malloc_chunk_command_heuristic(start_binary):
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -225,7 +225,7 @@ class mock_for_heuristic:
 
 def test_main_arena_heuristic(start_binary):
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -267,7 +267,7 @@ def test_main_arena_heuristic(start_binary):
 
 def test_mp_heuristic(start_binary):
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -303,7 +303,7 @@ def test_mp_heuristic(start_binary):
 def test_global_max_fast_heuristic(start_binary):
     # TODO: Support other architectures or different libc versions
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -331,7 +331,7 @@ def test_global_max_fast_heuristic(start_binary):
 def test_thread_cache_heuristic(start_binary):
     # TODO: Support other architectures or different libc versions
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -366,7 +366,7 @@ def test_thread_cache_heuristic(start_binary):
 def test_thread_arena_heuristic(start_binary):
     # TODO: Support other architectures or different libc versions
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 
@@ -395,7 +395,7 @@ def test_thread_arena_heuristic(start_binary):
 def test_heuristic_fail_gracefully(start_binary):
     # TODO: Support other architectures or different libc versions
     start_binary(HEAP_MALLOC_CHUNK)
-    gdb.execute("set resolve-heap-via-heuristic on")
+    gdb.execute("set resolve-heap-via-heuristic force")
     gdb.execute("break break_here")
     gdb.execute("continue")
 

tests/gdb-tests/tests/test_gdblib_parameter.py

@@ -35,10 +35,12 @@ def test_gdb_parameter_default_value_works(start_binary, params):
     param_name = f"test-param-{name_suffix}"
     help_docstring = f"Help docstring for {param_name}"
 
+    set_show_doc = "the value of the foo"
+
     param = pwndbg.gdblib.config.add_param(
         param_name,
         default_value,
-        "some show string",
+        set_show_doc,
         help_docstring=help_docstring,
         **optional_kwargs,
     )
@@ -47,7 +49,7 @@ def test_gdb_parameter_default_value_works(start_binary, params):
     pwndbg.gdblib.config_mod.Parameter(param)
 
     out = gdb.execute(f"show {param_name}", to_string=True)
-    assert out == f"The current value of {param_name!r} is {displayed_value!r}\n"
+    assert out == f"{set_show_doc.capitalize()} is {displayed_value!r}.\n"
     if (
         optional_kwargs.get("param_class") in (gdb.PARAM_UINTEGER, gdb.PARAM_INTEGER)
         and default_value == 0
@@ -62,10 +64,10 @@ def test_gdb_parameter_default_value_works(start_binary, params):
     assert param.value == default_value
 
     out = gdb.execute(f"help show {param_name}", to_string=True)
-    assert out == f"Show some show string\n{help_docstring}\n"
+    assert out == f"Show {set_show_doc}.\n{help_docstring}\n"
     assert (
         gdb.execute(f"help set {param_name}", to_string=True)
-        == f"Set some show string\n{help_docstring}\n"
+        == f"Set {set_show_doc}.\n{help_docstring}\n"
     )
 
     # TODO/FIXME: Is there a way to unregister a GDB parameter defined in Python?

tests/gdb-tests/tests/test_triggers.py

@@ -30,11 +30,15 @@ def test_triggers():
             set_show(param_name, 0)
             set_show(param_name, 1)
             set_show(param_name, -1)
-        elif isinstance(p.value, str):
+        elif isinstance(p.value, str) and p.param_class != gdb.PARAM_ENUM:
             set_show(param_name, "")
             set_show(param_name, "some invalid text")
             set_show(param_name, "red")
             set_show(param_name, "bold,yellow")
+        elif isinstance(p.value, str) and p.param_class == gdb.PARAM_ENUM:
+            # Only valid values are allowed, invalid values will cause an error
+            for enum in p.enum_sequence:
+                set_show(param_name, enum)
         else:
             print(p.value, type(p.value))
             assert False