struct lf_to_crlf_filter {
struct stream_filter filter;
- unsigned want_lf:1;
+ unsigned has_held:1;
+ char held;
};
static int lf_to_crlf_filter_fn(struct stream_filter *filter,
size_t count, o = 0;
struct lf_to_crlf_filter *lf_to_crlf = (struct lf_to_crlf_filter *)filter;
- /* Output a pending LF if we need to */
- if (lf_to_crlf->want_lf) {
- output[o++] = '\n';
- lf_to_crlf->want_lf = 0;
+ /*
+ * We may be holding onto the CR to see if it is followed by a
+ * LF, in which case we would need to go to the main loop.
+ * Otherwise, just emit it to the output stream.
+ */
+ if (lf_to_crlf->has_held && (lf_to_crlf->held != '\r' || !input)) {
+ output[o++] = lf_to_crlf->held;
+ lf_to_crlf->has_held = 0;
}
/* We are told to drain */
}
count = *isize_p;
- if (count) {
+ if (count || lf_to_crlf->has_held) {
size_t i;
+ int was_cr = 0;
+
+ if (lf_to_crlf->has_held) {
+ was_cr = 1;
+ lf_to_crlf->has_held = 0;
+ }
+
for (i = 0; o < *osize_p && i < count; i++) {
char ch = input[i];
+
if (ch == '\n') {
output[o++] = '\r';
- if (o >= *osize_p) {
- lf_to_crlf->want_lf = 1;
- continue; /* We need to increase i */
- }
+ } else if (was_cr) {
+ /*
+ * Previous round saw CR and it is not followed
+ * by a LF; emit the CR before processing the
+ * current character.
+ */
+ output[o++] = '\r';
}
+
+ /*
+ * We may have consumed the last output slot,
+ * in which case we need to break out of this
+ * loop; hold the current character before
+ * returning.
+ */
+ if (*osize_p <= o) {
+ lf_to_crlf->has_held = 1;
+ lf_to_crlf->held = ch;
+ continue; /* break but increment i */
+ }
+
+ if (ch == '\r') {
+ was_cr = 1;
+ continue;
+ }
+
+ was_cr = 0;
output[o++] = ch;
}
*osize_p -= o;
*isize_p -= i;
+
+ if (!lf_to_crlf->has_held && was_cr) {
+ lf_to_crlf->has_held = 1;
+ lf_to_crlf->held = '\r';
+ }
}
return 0;
}