/**
* Read data from the pmsg list into supplied buffer. Copied data is
* removed from the list.
*
* @param slist the pmsg list
* @param buf start of buffer where data must be copied
* @param len length of buffer
*
* @return amount of copied bytes.
*/
size_t
pmsg_slist_read(slist_t *slist, void *buf, size_t len)
{
slist_iter_t *iter;
size_t remain = len;
void *p;
g_assert(slist != NULL);
iter = slist_iter_removable_on_head(slist);
p = buf;
while (remain != 0 && slist_iter_has_item(iter)) {
pmsg_t *mb = slist_iter_current(iter);
int n;
n = pmsg_read(mb, p, remain);
remain -= n;
p = ptr_add_offset(p, n);
if (0 == pmsg_size(mb)) { /* Fully copied message */
pmsg_free(mb);
slist_iter_remove(iter); /* Warning: moves to next */
} else {
break; /* No need to continue on partial copy */
}
}
slist_iter_free(&iter);
return len - remain;
}
/**
* Discard `n_bytes' from the pmsg_t buffer slist and free all completely
* discarded buffers.
*/
void
pmsg_slist_discard(slist_t *slist, size_t n_bytes)
{
slist_iter_t *iter;
g_assert(slist);
iter = slist_iter_removable_on_head(slist);
while (n_bytes > 0) {
pmsg_t *mb;
size_t size;
g_assert(slist_iter_has_item(iter));
mb = slist_iter_current(iter);
pmsg_check_consistency(mb);
size = pmsg_size(mb);
if (size > n_bytes) {
pmsg_discard(mb, n_bytes);
break;
} else {
pmsg_free(mb);
n_bytes -= size;
slist_iter_remove(iter);
}
}
slist_iter_free(&iter);
}
/**
* Creates an iovec from a singly-linked list of pmsg_t buffers.
* It should be freed via hfree().
*
* NOTE: The iovec will hold no more than MAX_IOV_COUNT items. That means
* the iovec might not cover the whole buffered data. This limit
* is applied because writev() could fail with EINVAL otherwise
* which would simply add more unnecessary complexity.
*/
iovec_t *
pmsg_slist_to_iovec(slist_t *slist, int *iovcnt_ptr, size_t *size_ptr)
{
iovec_t *iov;
size_t held = 0;
int n;
g_assert(slist);
n = slist_length(slist);
if (n > 0) {
slist_iter_t *iter;
int i;
n = MIN(n, MAX_IOV_COUNT);
iov = halloc(n * sizeof *iov);
iter = slist_iter_before_head(slist);
for (i = 0; i < n; i++) {
pmsg_t *mb;
size_t size;
mb = slist_iter_next(iter);
pmsg_check_consistency(mb);
size = pmsg_size(mb);
g_assert(size > 0);
held += size;
iovec_set(&iov[i], deconstify_pointer(pmsg_read_base(mb)), size);
}
slist_iter_free(&iter);
} else {
iov = NULL;
}
if (iovcnt_ptr) {
*iovcnt_ptr = MAX(0, n);
}
if (size_ptr) {
*size_ptr = held;
}
return iov;
}
/**
* Dump field on specified file descriptor.
*/
static void
hfield_dump(const header_field_t *h, FILE *out)
{
slist_iter_t *iter;
bool first;
header_field_check(h);
g_assert(h->lines);
fprintf(out, "%s: ", h->name);
first = TRUE;
iter = slist_iter_on_head(h->lines);
for (/* NOTHING */; slist_iter_has_item(iter); slist_iter_next(iter)) {
const char *s;
if (first)
first = FALSE;
else
fputs(" ", out); /* Continuation line */
s = slist_iter_current(iter);
if (is_printable_iso8859_string(s)) {
fputs(s, out);
} else {
char buf[80];
const char *p = s;
int c;
size_t len = strlen(s);
str_bprintf(buf, sizeof buf, "<%u non-printable byte%s>",
(unsigned) len, plural(len));
fputs(buf, out);
while ((c = *p++)) {
if (is_ascii_print(c) || is_ascii_space(c))
fputc(c, out);
else
fputc('.', out); /* Less visual clutter than '?' */
}
}
fputc('\n', out);
}
slist_iter_free(&iter);
}
/**
* Returns the size of the data held in the buffer list.
*/
size_t
pmsg_slist_size(const slist_t *slist)
{
slist_iter_t *iter;
size_t size = 0;
g_assert(slist != NULL);
iter = slist_iter_before_head(slist);
while (slist_iter_has_next(iter)) {
const pmsg_t *mb;
mb = slist_iter_next(iter);
pmsg_check_consistency(mb);
size += pmsg_size(mb);
}
slist_iter_free(&iter);
return size;
}
