Author: rhuijben
Date: Mon Nov 2 13:46:40 2015
New Revision: 1711984
URL: http://svn.apache.org/viewvc?rev=1711984&view=rev
Log:
Simplify some code in the copy bucket code and avoid copying data
(and allocating the buffer) in a not unlikely scenario.
* buckets/copy_buckets.c
(serf__copy_iovec): New helper function.
(serf_copy_read): Avoid allocating+copying when we only return
the first result of the iovec read. Extract copy code.
(serf_copy_read_iovec): Extract copy code to improve readability.
Modified:
serf/trunk/buckets/copy_buckets.c
Modified: serf/trunk/buckets/copy_buckets.c
URL:
http://svn.apache.org/viewvc/serf/trunk/buckets/copy_buckets.c?rev=1711984&r1=1711983&r2=1711984&view=diff
==============================================================================
--- serf/trunk/buckets/copy_buckets.c (original)
+++ serf/trunk/buckets/copy_buckets.c Mon Nov 2 13:46:40 2015
@@ -58,6 +58,24 @@ serf_bucket_t *serf_bucket_copy_create(
return serf_bucket_create(&serf_bucket_type_copy, allocator, ctx);
}
+static void serf__copy_iovec(char *data,
+ apr_size_t *copied,
+ struct iovec *vecs,
+ int vecs_used)
+{
+ int i;
+ apr_size_t sz = 0;
+
+ for (i = 0; i < vecs_used; i++) {
+ memcpy(data, vecs[i].iov_base, vecs[i].iov_len);
+ data += vecs[i].iov_len;
+ sz += vecs[i].iov_len;
+ }
+
+ if (copied)
+ *copied = sz;
+}
+
static apr_status_t serf_copy_read(serf_bucket_t *bucket,
apr_size_t requested,
const char **data, apr_size_t *len)
@@ -66,8 +84,6 @@ static apr_status_t serf_copy_read(serf_
apr_status_t status;
const char *wdata;
apr_size_t peek_len;
- struct iovec vecs[16];
- int vecs_used;
apr_size_t fetched;
status = serf_bucket_peek(ctx->wrapped, &wdata, &peek_len);
@@ -83,17 +99,16 @@ static apr_status_t serf_copy_read(serf_
return serf_bucket_read(ctx->wrapped, requested, data, len);
}
- if (! ctx->hold_buf)
- ctx->hold_buf = serf_bucket_mem_alloc(bucket->allocator,
- ctx->min_size);
-
- /* Reduce requested to fit in our buffer if necessary*/
+ /* Reduce requested to fit in our buffer */
if (requested > ctx->min_size)
requested = ctx->min_size;
fetched = 0;
while (fetched < requested) {
- int i;
+ struct iovec vecs[16];
+ int vecs_used;
+ apr_size_t read;
+
status = serf_bucket_read_iovec(ctx->wrapped, requested - fetched,
16, vecs, &vecs_used);
@@ -102,12 +117,31 @@ static apr_status_t serf_copy_read(serf_
status = APR_EAGAIN;
break;
}
+ else if (!fetched && vecs_used == 1
+ && (status || (vecs[0].iov_len == requested))) {
+
+ /* Easy out
+ * We don't have anything stashed
+ * We only have one buffer to return
+ * And either
+ - We can't read any further at this time
+ - Or the buffer is already filled
+ */
+
+ *data = vecs[0].iov_base;
+ *len = vecs[0].iov_len;
+ return status;
+ }
+ else if (!ctx->hold_buf && vecs_used > 0) {
+ /* We have something that we want to store */
- for (i = 0; i < vecs_used; i++) {
- memcpy(ctx->hold_buf + fetched, vecs[i].iov_base, vecs[i].iov_len);
- fetched += vecs[i].iov_len;
+ ctx->hold_buf = serf_bucket_mem_alloc(bucket->allocator,
+ ctx->min_size);
}
+ serf__copy_iovec(ctx->hold_buf + fetched, &read, vecs, vecs_used);
+ fetched += read;
+
if (status)
break;
}
@@ -196,12 +230,8 @@ static apr_status_t serf_copy_read_iovec
ctx->min_size);
/* ### copy into HOLD_BUF. then read/append some more. */
- fetched = 0;
- for (i = 0; i < *vecs_used; i++) {
- memcpy(ctx->hold_buf + fetched, vecs[i].iov_base, vecs[i].iov_len);
- fetched += vecs[i].iov_len;
- }
-
+ fetched = total;
+ serf__copy_iovec(ctx->hold_buf, NULL, vecs, *vecs_used);
/* ### point vecs[0] at HOLD_BUF. */
vecs[0].iov_base = ctx->hold_buf;
@@ -226,12 +256,9 @@ static apr_status_t serf_copy_read_iovec
return status;
}
- for (i = 1; i <= v_used; i++) {
- memcpy(ctx->hold_buf + fetched, vecs[i].iov_base,
- vecs[i].iov_len);
- fetched += vecs[i].iov_len;
- }
+ serf__copy_iovec(ctx->hold_buf + fetched, NULL, &vecs[1], v_used);
+ fetched += total;
vecs[0].iov_len = fetched;
}
}
