Refine the 'watchpoint set' command to now require either the '-v' option (for watching of a variable) or
the '-e' option (for watching of an address) to be present.
Update some existing test cases with the required option and add some more test cases.
Since the '-v' option takes <variable-name> and the '-e' option takes <expr> as the command arg,
the existing infrastructure for generating the option usage can produce confusing help message,
like:
watchpoint set -e [-w <watch-type>] [-x <byte-size>] <variable-name | expr>
watchpoint set -v [-w <watch-type>] [-x <byte-size>] <variable-name | expr>
The solution adopted is to provide an extra member field to the struct CommandArgumentData called
(uint32_t)arg_opt_set_association, whose purpose is to link this particular argument data with some
option set(s). Also modify the signature of CommandObject::GetFormattedCommandArguments() to:
GetFormattedCommandArguments (Stream &str, uint32_t opt_set_mask = LLDB_OPT_SET_ALL)
it now takes an additional opt_set_mask which can be used to generate a filtered formatted command
args for help message.
Options::GenerateOptionUsage() impl is modified to call the GetFormattedCommandArguments() appropriately.
So that the help message now looks like:
watchpoint set -e [-w <watch-type>] [-x <byte-size>] <expr>
watchpoint set -v [-w <watch-type>] [-x <byte-size>] <variable-name>
rdar://problem/10703256
git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@150032 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Commands/CommandObjectWatchpoint.cpp b/source/Commands/CommandObjectWatchpoint.cpp
index f72a900..bb715d8 100644
--- a/source/Commands/CommandObjectWatchpoint.cpp
+++ b/source/Commands/CommandObjectWatchpoint.cpp
@@ -853,6 +853,70 @@
}
//-------------------------------------------------------------------------
+// CommandObjectWatchpointSet::CommandOptions
+//-------------------------------------------------------------------------
+#pragma mark Set::CommandOptions
+
+CommandObjectWatchpointSet::CommandOptions::CommandOptions() :
+ OptionGroup()
+{
+}
+
+CommandObjectWatchpointSet::CommandOptions::~CommandOptions ()
+{
+}
+
+OptionDefinition
+CommandObjectWatchpointSet::CommandOptions::g_option_table[] =
+{
+{ LLDB_OPT_SET_1, true, "expression", 'e', no_argument, NULL, NULL, eArgTypeNone, "Watch an address with an expression specified at the end."},
+{ LLDB_OPT_SET_2, true, "variable", 'v', no_argument, NULL, NULL, eArgTypeNone, "Watch a variable name specified at the end."}
+};
+
+uint32_t
+CommandObjectWatchpointSet::CommandOptions::GetNumDefinitions ()
+{
+ return sizeof(g_option_table)/sizeof(OptionDefinition);
+}
+
+const OptionDefinition*
+CommandObjectWatchpointSet::CommandOptions::GetDefinitions ()
+{
+ return g_option_table;
+}
+
+Error
+CommandObjectWatchpointSet::CommandOptions::SetOptionValue (CommandInterpreter &interpreter,
+ uint32_t option_idx,
+ const char *option_arg)
+{
+ Error error;
+ char short_option = (char) g_option_table[option_idx].short_option;
+
+ switch (short_option)
+ {
+ case 'e':
+ m_do_expression = true;
+ break;
+ case 'v':
+ m_do_variable = true;
+ break;
+ default:
+ error.SetErrorStringWithFormat ("unrecognized option '%c'", short_option);
+ break;
+ }
+
+ return error;
+}
+
+void
+CommandObjectWatchpointSet::CommandOptions::OptionParsingStarting (CommandInterpreter &interpreter)
+{
+ m_do_expression = false;
+ m_do_variable = false;
+}
+
+//-------------------------------------------------------------------------
// CommandObjectWatchpointSet
//-------------------------------------------------------------------------
#pragma mark Set
@@ -861,45 +925,51 @@
CommandObject (interpreter,
"watchpoint set",
"Set a watchpoint. "
- "You can choose to watch a variable in scope with just the '-w' option. "
- "If you use the '-x' option to specify the byte size, it is implied "
- "that the remaining string is evaluated as an expression with the result "
- "interpreted as an address to watch for, i.e., the pointee is watched. "
+ "You can choose to watch a variable in scope with the '-v' option "
+ "or to watch an address with the '-e' option by supplying an expression. "
+ "Use the '-w' option to specify the type of watchpoint and "
+ "the '-x' option to specify the byte size to watch for. "
"If no '-w' option is specified, it defaults to read_write. "
"Note that hardware resources for watching are often limited.",
NULL,
eFlagProcessMustBeLaunched | eFlagProcessMustBePaused),
m_option_group (interpreter),
- m_option_watchpoint()
+ m_option_watchpoint (),
+ m_command_options ()
{
SetHelpLong(
"Examples: \n\
\n\
- watchpoint set -w read_wriate my_global_var \n\
- # Watch my_global_var for read/write access.\n\
+ watchpoint set -w read_wriate -v my_global_var \n\
+ # Watch my_global_var for read/write access, with the region to watch corresponding to the byte size of the data type.\n\
\n\
- watchpoint set -w write -x 1 foo + 32\n\
- # Watch write access for the 1-byte region pointed to by the address 'foo + 32'.\n");
+ watchpoint set -w write -x 1 -e foo + 32\n\
+ # Watch write access for the 1-byte region pointed to by the address 'foo + 32'.\n\
+ # If no '-x' option is specified, byte size defaults to 4.\n");
CommandArgumentEntry arg;
CommandArgumentData var_name_arg, expression_arg;
// Define the first variant of this arg.
- var_name_arg.arg_type = eArgTypeVarName;
- var_name_arg.arg_repetition = eArgRepeatPlain;
-
- // Define the second variant of this arg.
expression_arg.arg_type = eArgTypeExpression;
expression_arg.arg_repetition = eArgRepeatPlain;
+ expression_arg.arg_opt_set_association = LLDB_OPT_SET_1;
+ // Define the second variant of this arg.
+ var_name_arg.arg_type = eArgTypeVarName;
+ var_name_arg.arg_repetition = eArgRepeatPlain;
+ var_name_arg.arg_opt_set_association = LLDB_OPT_SET_2;
+
// Push the two variants into the argument entry.
- arg.push_back (var_name_arg);
arg.push_back (expression_arg);
+ arg.push_back (var_name_arg);
- // Push the data for the first argument into the m_arguments vector.
+ // Push the data for the only argument into the m_arguments vector.
m_arguments.push_back (arg);
-
- m_option_group.Append (&m_option_watchpoint, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
+
+ // Absorb the '-w' and '-x' options.
+ m_option_group.Append (&m_option_watchpoint, LLDB_OPT_SET_1, LLDB_OPT_SET_1|LLDB_OPT_SET_2);
+ m_option_group.Append (&m_command_options);
m_option_group.Finalize();
}
@@ -930,35 +1000,25 @@
return false;
}
- // Be careful about the stack frame, if any summary formatter runs code, it might clear the StackFrameList
- // for the thread. So hold onto a shared pointer to the frame so it stays alive.
- bool get_file_globals = true;
- VariableList *variable_list = frame->GetVariableList (get_file_globals);
+ // If no argument is present, issue an error message. There's no way to set a watchpoint.
+ if (command.GetArgumentCount() <= 0)
+ {
+ result.GetErrorStream().Printf("error: required argument missing; specify your program variable ('-v') or an address ('-e') to watch for\n");
+ result.SetStatus(eReturnStatusFailed);
+ return false;
+ }
- bool watch_address = (m_option_watchpoint.watch_size > 0);
-
+ // It's either '-e' to watch an address with expression' or '-v' to watch a variable.
+ bool watch_address = m_command_options.m_do_expression;
+
// If no '-w' is specified, default to '-w read_write'.
if (!m_option_watchpoint.watch_variable)
{
m_option_watchpoint.watch_variable = true;
m_option_watchpoint.watch_type = OptionGroupWatchpoint::eWatchReadWrite;
}
- // It's possible to specify an address to watch for with the '-x' option.
- if (!variable_list && !watch_address)
- {
- result.GetErrorStream().Printf("error: no variables found, did you forget to use '-x' option to watch an address?\n");
- result.SetStatus(eReturnStatusFailed);
- return false;
- }
- // If thre's no argument, it is an error.
- if (command.GetArgumentCount() <= 0)
- {
- result.GetErrorStream().Printf("error: specify your target variable (no '-x') or expression (with '-x') to watch for\n");
- result.SetStatus(eReturnStatusFailed);
- return false;
- }
- // We passed the sanity check for the options.
+ // We passed the sanity check for the command.
// Proceed to set the watchpoint now.
lldb::addr_t addr = 0;
size_t size = 0;
@@ -968,6 +1028,7 @@
Stream &output_stream = result.GetOutputStream();
if (watch_address) {
+ // Use expression evaluation to arrive at the address to watch.
std::string expr_str;
command.GetQuotedCommandString(expr_str);
const bool coerce_to_id = true;
@@ -983,6 +1044,7 @@
valobj_sp);
if (expr_result != eExecutionCompleted) {
result.GetErrorStream().Printf("error: expression evaluation of address to watch failed\n");
+ result.GetErrorStream().Printf("expression evaluated: %s\n", expr_str.c_str());
result.SetStatus(eReturnStatusFailed);
}
@@ -993,11 +1055,12 @@
result.SetStatus(eReturnStatusFailed);
return false;
}
- size = m_option_watchpoint.watch_size;
+ size = m_option_watchpoint.watch_size == 0 ? 4 /* Could use a better default size? */
+ : m_option_watchpoint.watch_size;
} else {
// A simple watch variable gesture allows only one argument.
- if (m_option_watchpoint.watch_size == 0 && command.GetArgumentCount() != 1) {
- result.GetErrorStream().Printf("error: specify exactly one variable with the '-w' option, i.e., no '-x'\n");
+ if (command.GetArgumentCount() != 1) {
+ result.GetErrorStream().Printf("error: specify exactly one variable with the '-v' option\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
@@ -1016,7 +1079,8 @@
if (addr_type == eAddressTypeLoad) {
// We're in business.
// Find out the size of this variable.
- size = valobj_sp->GetByteSize();
+ size = m_option_watchpoint.watch_size == 0 ? valobj_sp->GetByteSize()
+ : m_option_watchpoint.watch_size;
}
} else {
const char *error_cstr = error.AsCString(NULL);
@@ -1045,7 +1109,8 @@
output_stream.EOL();
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
- result.AppendErrorWithFormat("Watchpoint creation failed.\n");
+ result.AppendErrorWithFormat("Watchpoint creation failed (addr=0x%llx, size=%lu).\n",
+ addr, size);
result.SetStatus(eReturnStatusFailed);
}