[c++,06/12] Fix constness problem in ioscm_make_gdb_stdio_port
Commit Message
ioscm_make_gdb_stdio_port passes const char pointers (literal strings) to
scm_mode_bits, which takes a non-const char pointer. Ideally, we would
change scm_mode_bits to take a const char pointer, but it's not part of
an API we control.
Instead, it's easy enough to build the string to pass to scm_mode_bits in
a (non-const) char array and pass that.
gdb/ChangeLog:
* guile/scm-ports.c (ioscm_make_gdb_stdio_port): Pass non-const
char pointer to scm_mode_bits.
---
gdb/guile/scm-ports.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
Comments
Simon Marchi <simon.marchi@polymtl.ca> writes:
> ioscm_make_gdb_stdio_port passes const char pointers (literal strings) to
> scm_mode_bits, which takes a non-const char pointer. Ideally, we would
> change scm_mode_bits to take a const char pointer, but it's not part of
> an API we control.
>
> Instead, it's easy enough to build the string to pass to scm_mode_bits in
> a (non-const) char array and pass that.
>
> gdb/ChangeLog:
>
> * guile/scm-ports.c (ioscm_make_gdb_stdio_port): Pass non-const
> char pointer to scm_mode_bits.
> ---
> gdb/guile/scm-ports.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/gdb/guile/scm-ports.c b/gdb/guile/scm-ports.c
> index 925f3b2..49e4fd6 100644
> --- a/gdb/guile/scm-ports.c
> +++ b/gdb/guile/scm-ports.c
> @@ -357,29 +357,38 @@ ioscm_init_stdio_buffers (SCM port, long mode_bits)
> static SCM
> ioscm_make_gdb_stdio_port (int fd)
> {
> - int is_a_tty = isatty (fd);
> const char *name;
> long mode_bits;
> SCM port;
> + char buf[3];
> +
> + memset (buf, 0, sizeof (buf));
>
> switch (fd)
> {
> case 0:
> name = input_port_name;
> - mode_bits = scm_mode_bits (is_a_tty ? "r0" : "r");
> + buf[0] = 'r';
> break;
> case 1:
> name = output_port_name;
> - mode_bits = scm_mode_bits (is_a_tty ? "w0" : "w");
> + buf[0] = 'w';
> break;
> case 2:
> name = error_port_name;
> - mode_bits = scm_mode_bits (is_a_tty ? "w0" : "w");
> + buf[0] = 'w';
> break;
> default:
> gdb_assert_not_reached ("bad stdio file descriptor");
> }
>
> + if (isatty (fd))
> + {
> + buf[1] = '0';
> + }
Community rules say to not use braces here.
Ok with that change.
> +
> + mode_bits = scm_mode_bits (buf);
> +
> port = ioscm_open_port (stdio_port_desc, mode_bits);
>
> scm_set_port_filename_x (port, gdbscm_scm_from_c_string (name));
@@ -357,29 +357,38 @@ ioscm_init_stdio_buffers (SCM port, long mode_bits)
static SCM
ioscm_make_gdb_stdio_port (int fd)
{
- int is_a_tty = isatty (fd);
const char *name;
long mode_bits;
SCM port;
+ char buf[3];
+
+ memset (buf, 0, sizeof (buf));
switch (fd)
{
case 0:
name = input_port_name;
- mode_bits = scm_mode_bits (is_a_tty ? "r0" : "r");
+ buf[0] = 'r';
break;
case 1:
name = output_port_name;
- mode_bits = scm_mode_bits (is_a_tty ? "w0" : "w");
+ buf[0] = 'w';
break;
case 2:
name = error_port_name;
- mode_bits = scm_mode_bits (is_a_tty ? "w0" : "w");
+ buf[0] = 'w';
break;
default:
gdb_assert_not_reached ("bad stdio file descriptor");
}
+ if (isatty (fd))
+ {
+ buf[1] = '0';
+ }
+
+ mode_bits = scm_mode_bits (buf);
+
port = ioscm_open_port (stdio_port_desc, mode_bits);
scm_set_port_filename_x (port, gdbscm_scm_from_c_string (name));