[PATCH v2 04/31] cli-script.c: Simplify using std::string, eliminate cleanups

Pedro Alves
2016-10-19T01:19:33Z

yyyy-mm-dd Pedro Alves <palves@redhat.com>

* cli/cli-script.c (execute_control_command): Use std::string
instead of cleanups.
(locate_arg): Constify return type.
(insert_args): Constify paremeter. Simplify using std::string.
Return a std::string.
---
gdb/cli/cli-script.c | 110 ++++++++++++++++-----------------------------------
1 file changed, 33 insertions(+), 77 deletions(-)

diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c
index c36cce6..6f1cc8a 100644
--- a/gdb/cli/cli-script.c
+++ b/gdb/cli/cli-script.c
@@ -41,7 +41,7 @@ recurse_read_control_structure (char * (*read_next_line_func) (void),
void (*validator)(char *, void *),
void *closure);

-static char *insert_args (char *line);
+static std::string insert_args (const char *line);

static struct cleanup * setup_user_args (char *p);

@@ -448,7 +448,6 @@ execute_control_command (struct command_line *cmd)
struct value *val_mark;
int loop;
enum command_control_type ret;
- char *new_line;

/* Start by assuming failure, if a problem is detected, the code
below will simply "break" out of the switch. */
@@ -457,12 +456,13 @@ execute_control_command (struct command_line *cmd)
switch (cmd->control_type)
{
case simple_control:
- /* A simple command, execute it and return. */
- new_line = insert_args (cmd->line);
- make_cleanup (free_current_contents, &new_line);
- execute_command (new_line, 0);
- ret = cmd->control_type;
- break;
+ {
+ /* A simple command, execute it and return. */
+ std::string new_line = insert_args (cmd->line);
+ execute_command (&new_line[0], 0);
+ ret = cmd->control_type;
+ break;
+ }

case continue_control:
print_command_trace ("loop_continue");
@@ -489,9 +489,8 @@ execute_control_command (struct command_line *cmd)
print_command_trace (buffer);

/* Parse the loop control expression for the while statement. */
- new_line = insert_args (cmd->line);
- make_cleanup (free_current_contents, &new_line);
- expr = parse_expression (new_line);
+ std::string new_line = insert_args (cmd->line);
+ expr = parse_expression (new_line.c_str ());
make_cleanup (free_current_contents, &expr);

ret = simple_control;
@@ -555,10 +554,9 @@ execute_control_command (struct command_line *cmd)
xsnprintf (buffer, len, "if %s", cmd->line);
print_command_trace (buffer);

- new_line = insert_args (cmd->line);
- make_cleanup (free_current_contents, &new_line);
/* Parse the conditional for the if statement. */
- expr = parse_expression (new_line);
+ std::string new_line = insert_args (cmd->line);
+ expr = parse_expression (new_line.c_str ());
make_cleanup (free_current_contents, &expr);

current = NULL;
@@ -598,9 +596,8 @@ execute_control_command (struct command_line *cmd)
{
/* Breakpoint commands list, record the commands in the
breakpoint's command list and return. */
- new_line = insert_args (cmd->line);
- make_cleanup (free_current_contents, &new_line);
- ret = commands_from_control_command (new_line, cmd);
+ std::string new_line = insert_args (cmd->line);
+ ret = commands_from_control_command (new_line.c_str (), cmd);
break;
}

@@ -786,8 +783,8 @@ setup_user_args (char *p)
/* Given character string P, return a point to the first argument
($arg), or NULL if P contains no arguments. */

-static char *
-locate_arg (char *p)
+static const char *
+locate_arg (const char *p)
{
while ((p = strchr (p, '$')))
{
@@ -800,93 +797,52 @@ locate_arg (char *p)
}

/* Insert the user defined arguments stored in user_arg into the $arg
- arguments found in line, with the updated copy being placed into
- nline. */
+ arguments found in line. */

-static char *
-insert_args (char *line)
+static std::string
+insert_args (const char *line)
{
- char *p, *save_line, *new_line;
- unsigned len, i;
-
/* If we are not in a user-defined function, treat $argc, $arg0, et
cetera as normal convenience variables. */
if (user_args == NULL)
- return xstrdup (line);
+ return line;

- /* First we need to know how much memory to allocate for the new
- line. */
- save_line = line;
- len = 0;
- while ((p = locate_arg (line)))
- {
- len += p - line;
- i = p[4] - '0';
-
- if (p[4] == 'c')
- {
- /* $argc. Number will be <=10. */
- len += user_args->count == 10 ? 2 : 1;
- }
- else if (i >= user_args->count)
- {
- error (_("Missing argument %d in user function."), i);
- return NULL;
- }
- else
- {
- len += user_args->a[i].len;
- }
- line = p + 5;
- }
-
- /* Don't forget the tail. */
- len += strlen (line);
-
- /* Allocate space for the new line and fill it in. */
- new_line = (char *) xmalloc (len + 1);
-
- /* Restore pointer to beginning of old line. */
- line = save_line;
-
- /* Save pointer to beginning of new line. */
- save_line = new_line;
+ std::string new_line;
+ const char *p;

while ((p = locate_arg (line)))
{
int i, len;

- memcpy (new_line, line, p - line);
- new_line += p - line;
+ new_line.append (line, p - line);

if (p[4] == 'c')
{
gdb_assert (user_args->count >= 0 && user_args->count <= 10);
if (user_args->count == 10)
{
- *(new_line++) = '1';
- *(new_line++) = '0';
+ new_line += '1';
+ new_line += '0';
}
else
- *(new_line++) = user_args->count + '0';
+ new_line += user_args->count + '0';
}
else
{
i = p[4] - '0';
+ if (i >= user_args->count)
+ error (_("Missing argument %d in user function."), i);
+
len = user_args->a[i].len;
- if (len)
- {
- memcpy (new_line, user_args->a[i].arg, len);
- new_line += len;
- }
+ if (len > 0)
+ new_line.append (user_args->a[i].arg, len);
}
line = p + 5;
}
/* Don't forget the tail. */
- strcpy (new_line, line);
+ new_line.append (line);

- /* Return a pointer to the beginning of the new line. */
- return save_line;
+ return new_line;
}

\f
--
2.5.5