/* places a single char in the input buffer. */
static int
sf_fill_input (SCM port)
{
SCM p = SCM_PACK (SCM_STREAM (port));
SCM ans;
scm_t_port *pt;
ans = scm_call_0 (SCM_SIMPLE_VECTOR_REF (p, 3)); /* get char. */
if (scm_is_false (ans) || SCM_EOF_OBJECT_P (ans))
return EOF;
SCM_ASSERT (SCM_CHARP (ans), ans, SCM_ARG1, "sf_fill_input");
pt = SCM_PTAB_ENTRY (port);
if (pt->encoding == NULL)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
*pt->read_buf = SCM_CHAR (ans);
pt->read_pos = pt->read_buf;
pt->read_end = pt->read_buf + 1;
return *pt->read_buf;
}
else
scm_ungetc_unlocked (SCM_CHAR (ans), port);
return SCM_CHAR (ans);
}
static void
gdbscm_memory_port_end_input (SCM port, int offset)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
size_t remaining = pt->read_end - pt->read_pos;
/* Note: Use of "int offset" is specified by Guile ports API. */
if ((offset < 0 && remaining + offset > remaining)
|| (offset > 0 && remaining + offset < remaining))
{
gdbscm_out_of_range_error (FUNC_NAME, 0, scm_from_int (offset),
_("overflow in offset calculation"));
}
offset += remaining;
if (offset > 0)
{
pt->read_pos = pt->read_end;
/* Throw error if unread-char used at beginning of file
then attempting to write. Seems correct. */
if (!ioscm_lseek_address (iomem, -offset, SEEK_CUR))
{
gdbscm_out_of_range_error (FUNC_NAME, 0, scm_from_int (offset),
_("bad offset"));
}
}
pt->rw_active = SCM_PORT_NEITHER;
}
static void
gdbscm_memory_port_flush (SCM port)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
size_t to_write = pt->write_pos - pt->write_buf;
if (to_write == 0)
return;
/* There's no way to indicate a short write, so if the request goes past
the end of the port's memory range, flag an error. */
if (to_write > iomem->size - iomem->current)
{
gdbscm_out_of_range_error (FUNC_NAME, 0,
gdbscm_scm_from_ulongest (to_write),
_("writing beyond end of memory range"));
}
if (target_write_memory (iomem->start + iomem->current, pt->write_buf,
to_write) != 0)
gdbscm_memory_error (FUNC_NAME, _("error writing memory"), SCM_EOL);
iomem->current += to_write;
pt->write_pos = pt->write_buf;
pt->rw_active = SCM_PORT_NEITHER;
}
static int
gdbscm_memory_port_fill_input (SCM port)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
size_t to_read;
/* "current" is the offset of the first byte we want to read. */
gdb_assert (iomem->current <= iomem->size);
if (iomem->current == iomem->size)
return EOF;
/* Don't read outside the allowed memory range. */
to_read = pt->read_buf_size;
if (to_read > iomem->size - iomem->current)
to_read = iomem->size - iomem->current;
if (target_read_memory (iomem->start + iomem->current, pt->read_buf,
to_read) != 0)
gdbscm_memory_error (FUNC_NAME, _("error reading memory"), SCM_EOL);
iomem->current += to_read;
pt->read_pos = pt->read_buf;
pt->read_end = pt->read_buf + to_read;
return *pt->read_buf;
}
static void
ioscm_reinit_memory_port (SCM port, size_t read_buf_size,
size_t write_buf_size, const char *func_name)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
gdb_assert (read_buf_size >= min_memory_port_buf_size
&& read_buf_size <= max_memory_port_buf_size);
gdb_assert (write_buf_size >= min_memory_port_buf_size
&& write_buf_size <= max_memory_port_buf_size);
/* First check if the port is unbuffered. */
if (pt->read_buf == &pt->shortbuf)
{
gdb_assert (pt->write_buf == &pt->shortbuf);
scm_misc_error (func_name, _("port is unbuffered: ~a"),
scm_list_1 (port));
}
/* Next check if anything is buffered. */
if (read_buf_size != pt->read_buf_size
&& pt->read_end != pt->read_buf)
{
scm_misc_error (func_name, _("read buffer not empty: ~a"),
scm_list_1 (port));
}
if (write_buf_size != pt->write_buf_size
&& pt->write_pos != pt->write_buf)
{
scm_misc_error (func_name, _("write buffer not empty: ~a"),
scm_list_1 (port));
}
/* Now we can update the buffer sizes, but only if the size has changed. */
if (read_buf_size != pt->read_buf_size)
{
iomem->read_buf_size = read_buf_size;
pt->read_buf_size = read_buf_size;
xfree (pt->read_buf);
pt->read_buf = (unsigned char *) xmalloc (pt->read_buf_size);
pt->read_pos = pt->read_end = pt->read_buf;
}
if (write_buf_size != pt->write_buf_size)
{
iomem->write_buf_size = write_buf_size;
pt->write_buf_size = write_buf_size;
xfree (pt->write_buf);
pt->write_buf = (unsigned char *) xmalloc (pt->write_buf_size);
pt->write_pos = pt->write_buf;
pt->write_end = pt->write_buf + pt->write_buf_size;
}
}
static int
sf_close (SCM port)
{
SCM p = SCM_PACK (SCM_STREAM (port));
SCM f = SCM_SIMPLE_VECTOR_REF (p, 4);
if (scm_is_false (f))
return 0;
f = scm_call_0 (f);
errno = 0;
return scm_is_false (f) ? EOF : 0;
}
static SCM
gdbscm_memory_port_write_buffer_size (SCM port)
{
ioscm_memory_port *iomem;
SCM_ASSERT_TYPE (gdbscm_is_memory_port (port), port, SCM_ARG1, FUNC_NAME,
memory_port_desc_name);
iomem = (ioscm_memory_port *) SCM_STREAM (port);
return scm_from_uint (iomem->write_buf_size);
}
static void
sf_write (SCM port, const void *data, size_t size)
{
SCM p = SCM_PACK (SCM_STREAM (port));
/* DATA is assumed to be a locale-encoded C string, which makes it
hard to reliably pass binary data to a soft port. It can be
achieved by choosing a Latin-1 locale, though, but the recommended
approach is to use an R6RS "custom binary output port" instead. */
scm_call_1 (SCM_SIMPLE_VECTOR_REF (p, 1),
scm_from_locale_stringn ((char *) data, size));
}
static SCM
gdbscm_memory_port_range (SCM port)
{
ioscm_memory_port *iomem;
SCM_ASSERT_TYPE (gdbscm_is_memory_port (port), port, SCM_ARG1, FUNC_NAME,
memory_port_desc_name);
iomem = (ioscm_memory_port *) SCM_STREAM (port);
return scm_list_2 (gdbscm_scm_from_ulongest (iomem->start),
gdbscm_scm_from_ulongest (iomem->end));
}
static int
sf_input_waiting (SCM port)
{
SCM p = SCM_PACK (SCM_STREAM (port));
if (SCM_SIMPLE_VECTOR_LENGTH (p) >= 6)
{
SCM f = SCM_SIMPLE_VECTOR_REF (p, 5);
if (scm_is_true (f))
return scm_to_int (scm_call_0 (f));
}
/* Default is such that char-ready? for soft ports returns #t, as it
did before this extension was implemented. */
return 1;
}
static int
gdbscm_memory_port_print (SCM exp, SCM port, scm_print_state *pstate)
{
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (exp);
char *type = SCM_PTOBNAME (SCM_PTOBNUM (exp));
scm_puts ("#<", port);
scm_print_port_mode (exp, port);
/* scm_print_port_mode includes a trailing space. */
gdbscm_printf (port, "%s %s-%s", type,
hex_string (iomem->start), hex_string (iomem->end));
scm_putc ('>', port);
return 1;
}
static int
gdbscm_memory_port_close (SCM port)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
gdbscm_memory_port_flush (port);
if (pt->read_buf == pt->putback_buf)
pt->read_buf = pt->saved_read_buf;
if (pt->read_buf != &pt->shortbuf)
xfree (pt->read_buf);
if (pt->write_buf != &pt->shortbuf)
xfree (pt->write_buf);
scm_gc_free (iomem, sizeof (*iomem), "memory port");
return 0;
}
/* Read one byte from PORT. */
static int
fill_input (SCM port)
{
int result;
scm_t_port *c_port = SCM_PTAB_ENTRY (port);
/* Make sure that C_PORT's internal buffer wasn't changed behind our back.
See http://lists.gnu.org/archive/html/guile-devel/2008-11/msg00042.html
for an example where this assumption matters. */
assert (c_port->read_buf == (unsigned char *) SCM_STREAM (port));
assert (c_port->read_buf_size == PORT_BUFFER_SIZE);
if (c_port->read_pos >= c_port->read_end)
result = EOF;
else
result = (int) *c_port->read_pos++;
return result;
}
static SCM
gdbscm_set_memory_port_write_buffer_size_x (SCM port, SCM size)
{
ioscm_memory_port *iomem;
SCM_ASSERT_TYPE (gdbscm_is_memory_port (port), port, SCM_ARG1, FUNC_NAME,
memory_port_desc_name);
SCM_ASSERT_TYPE (scm_is_integer (size), size, SCM_ARG2, FUNC_NAME,
_("integer"));
if (!scm_is_unsigned_integer (size, min_memory_port_buf_size,
max_memory_port_buf_size))
{
gdbscm_out_of_range_error (FUNC_NAME, SCM_ARG2, size,
out_of_range_buf_size);
}
iomem = (ioscm_memory_port *) SCM_STREAM (port);
ioscm_reinit_memory_port (port, iomem->read_buf_size, scm_to_uint (size),
FUNC_NAME);
return SCM_UNSPECIFIED;
}
static scm_t_off
gdbscm_memory_port_seek (SCM port, scm_t_off offset, int whence)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
CORE_ADDR result;
int rc;
if (pt->rw_active == SCM_PORT_WRITE)
{
if (offset != 0 || whence != SEEK_CUR)
{
gdbscm_memory_port_flush (port);
rc = ioscm_lseek_address (iomem, offset, whence);
result = iomem->current;
}
else
{
/* Read current position without disturbing the buffer,
but flag an error if what's in the buffer goes outside the
allowed range. */
CORE_ADDR current = iomem->current;
size_t delta = pt->write_pos - pt->write_buf;
if (current + delta < current
|| current + delta > iomem->size)
rc = 0;
else
{
result = current + delta;
rc = 1;
}
}
}
else if (pt->rw_active == SCM_PORT_READ)
{
if (offset != 0 || whence != SEEK_CUR)
{
scm_end_input (port);
rc = ioscm_lseek_address (iomem, offset, whence);
result = iomem->current;
}
else
{
/* Read current position without disturbing the buffer
(particularly the unread-char buffer). */
CORE_ADDR current = iomem->current;
size_t remaining = pt->read_end - pt->read_pos;
if (current - remaining > current
|| current - remaining < iomem->start)
rc = 0;
else
{
result = current - remaining;
rc = 1;
}
if (rc != 0 && pt->read_buf == pt->putback_buf)
{
size_t saved_remaining = pt->saved_read_end - pt->saved_read_pos;
if (result - saved_remaining > result
|| result - saved_remaining < iomem->start)
rc = 0;
else
result -= saved_remaining;
}
}
}
else /* SCM_PORT_NEITHER */
{
rc = ioscm_lseek_address (iomem, offset, whence);
result = iomem->current;
}
if (rc == 0)
{
gdbscm_out_of_range_error (FUNC_NAME, 0,
gdbscm_scm_from_longest (offset),
_("bad seek"));
}
/* TODO: The Guile API doesn't support 32x64. We can't fix that here,
and there's no need to throw an error if the new address can't be
represented in a scm_t_off. But we could return something less
clumsy. */
return result;
}
static void
gdbscm_memory_port_write (SCM port, const void *void_data, size_t size)
{
scm_t_port *pt = SCM_PTAB_ENTRY (port);
ioscm_memory_port *iomem = (ioscm_memory_port *) SCM_STREAM (port);
const gdb_byte *data = (const gdb_byte *) void_data;
/* There's no way to indicate a short write, so if the request goes past
the end of the port's memory range, flag an error. */
if (size > iomem->size - iomem->current)
{
gdbscm_out_of_range_error (FUNC_NAME, 0, gdbscm_scm_from_ulongest (size),
_("writing beyond end of memory range"));
}
if (pt->write_buf == &pt->shortbuf)
{
/* Unbuffered port. */
if (target_write_memory (iomem->start + iomem->current, data, size) != 0)
gdbscm_memory_error (FUNC_NAME, _("error writing memory"), SCM_EOL);
iomem->current += size;
return;
}
/* Note: The edge case of what to do when the buffer exactly fills is
debatable. Guile flushes when the buffer exactly fills up, so we
do too. It's counter-intuitive to my mind, but in case there's a
subtlety somewhere that depends on this, we do the same. */
{
size_t space = pt->write_end - pt->write_pos;
if (size < space)
{
/* Data fits in buffer, and does not fill it. */
memcpy (pt->write_pos, data, size);
pt->write_pos += size;
}
else
{
memcpy (pt->write_pos, data, space);
pt->write_pos = pt->write_end;
gdbscm_memory_port_flush (port);
{
const gdb_byte *ptr = data + space;
size_t remaining = size - space;
if (remaining >= pt->write_buf_size)
{
if (target_write_memory (iomem->start + iomem->current, ptr,
remaining) != 0)
gdbscm_memory_error (FUNC_NAME, _("error writing memory"),
SCM_EOL);
iomem->current += remaining;
}
else
{
memcpy (pt->write_pos, ptr, remaining);
pt->write_pos += remaining;
}
}
}
}
}
