Allow nonuniform buffer size in nghttp2_hd_deflate_hd_vec()

lib/includes/nghttp2/nghttp2.h

@@ -4604,14 +4604,12 @@ nghttp2_hd_deflate_hd(nghttp2_hd_deflater *deflater, uint8_t *buf,
  *
  * Deflates the |nva|, which has the |nvlen| name/value pairs, into
  * the |veclen| size of buf vector |vec|.  The each size of buffer
- * must be set in len field of :type:`nghttp2_vec`, and this function
- * assumes all buffer size is equal.  The application is responsible
- * to make sure that this assumption holds.  If one chunk is filled
- * up, next chunk will be used.  If |vec| is not large enough to store
- * the deflated header block, this function fails with
- * :enum:`NGHTTP2_ERR_INSUFF_BUFSIZE`.  The caller should use
- * `nghttp2_hd_deflate_bound()` to know the upper bound of buffer size
- * required to deflate given header name/value pairs.
+ * must be set in len field of :type:`nghttp2_vec`.  If and only if
+ * one chunk is filled up completely, next chunk will be used.  If
+ * |vec| is not large enough to store the deflated header block, this
+ * function fails with :enum:`NGHTTP2_ERR_INSUFF_BUFSIZE`.  The caller
+ * should use `nghttp2_hd_deflate_bound()` to know the upper bound of
+ * buffer size required to deflate given header name/value pairs.
  *
  * Once this function fails, subsequent call of this function always
  * returns :enum:`NGHTTP2_ERR_HEADER_COMP`.
@@ -4627,8 +4625,6 @@ nghttp2_hd_deflate_hd(nghttp2_hd_deflater *deflater, uint8_t *buf,
  *     Deflation process has failed.
  * :enum:`NGHTTP2_ERR_INSUFF_BUFSIZE`
  *     The provided |buflen| size is too small to hold the output.
- * :enum:`NGHTTP2_ERR_INVALID_ARGUMENT`
- *     The size of each buffer in |nva| is not the same.
  */
 NGHTTP2_EXTERN ssize_t
 nghttp2_hd_deflate_hd_vec(nghttp2_hd_deflater *deflater, const nghttp2_vec *vec,

lib/nghttp2_buf.c

@@ -224,13 +224,13 @@ int nghttp2_bufs_wrap_init(nghttp2_bufs *bufs, uint8_t *begin, size_t len,
 }
 
 int nghttp2_bufs_wrap_init2(nghttp2_bufs *bufs, const nghttp2_vec *vec,
-                            size_t veclen, size_t chunklen, nghttp2_mem *mem) {
+                            size_t veclen, nghttp2_mem *mem) {
   size_t i = 0;
   nghttp2_buf_chain *cur_chain;
   nghttp2_buf_chain *head_chain;
   nghttp2_buf_chain **dst_chain = &head_chain;
 
-  if (veclen == 0 || chunklen == 0) {
+  if (veclen == 0) {
     return nghttp2_bufs_wrap_init(bufs, NULL, 0, mem);
   }
 
@@ -254,7 +254,8 @@ int nghttp2_bufs_wrap_init2(nghttp2_bufs *bufs, const nghttp2_vec *vec,
   bufs->head = head_chain;
   bufs->cur = bufs->head;
 
-  bufs->chunk_length = chunklen;
+  /* We don't use chunk_length since no allocation is expected. */
+  bufs->chunk_length = 0;
   bufs->chunk_used = veclen;
   bufs->max_chunk = veclen;
   bufs->chunk_keep = veclen;

lib/nghttp2_buf.h

@@ -212,10 +212,10 @@ int nghttp2_bufs_wrap_init(nghttp2_bufs *bufs, uint8_t *begin, size_t len,
 
 /*
  * Initializes |bufs| using supplied |veclen| size of buf vector
- * |vec|, assuming that each buffer has length |chunklen|.  The buffer
- * size is fixed and no extra chunk buffer is allocated.  In other
- * words, max_chunk = chunk_keep = |in_len|.  To free the resource
- * allocated for |bufs|, use nghttp2_bufs_wrap_free().
+ * |vec|.  The number of buffers is fixed and no extra chunk buffer is
+ * allocated.  In other words, max_chunk = chunk_keep = |in_len|.  To
+ * free the resource allocated for |bufs|, use
+ * nghttp2_bufs_wrap_free().
  *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes:
@@ -224,7 +224,7 @@ int nghttp2_bufs_wrap_init(nghttp2_bufs *bufs, uint8_t *begin, size_t len,
  *     Out of memory.
  */
 int nghttp2_bufs_wrap_init2(nghttp2_bufs *bufs, const nghttp2_vec *vec,
-                            size_t veclen, size_t chunklen, nghttp2_mem *mem);
+                            size_t veclen, nghttp2_mem *mem);
 
 /*
  * Frees any related resource to the |bufs|.  This function does not

lib/nghttp2_hd.c

@@ -1509,25 +1509,11 @@ ssize_t nghttp2_hd_deflate_hd_vec(nghttp2_hd_deflater *deflater,
   nghttp2_bufs bufs;
   int rv;
   nghttp2_mem *mem;
-  size_t i;
   size_t buflen;
-  size_t chunklen;
-
-  if (veclen == 0) {
-    chunklen = 0;
-  } else {
-    for (i = 1; i < veclen; ++i) {
-      if (vec[0].len != vec[i].len) {
-        return NGHTTP2_ERR_INVALID_ARGUMENT;
-      }
-    }
-
-    chunklen = vec[0].len;
-  }
 
   mem = deflater->ctx.mem;
 
-  rv = nghttp2_bufs_wrap_init2(&bufs, vec, veclen, chunklen, mem);
+  rv = nghttp2_bufs_wrap_init2(&bufs, vec, veclen, mem);
 
   if (rv != 0) {
     return rv;

tests/nghttp2_hd_test.c

@@ -1352,14 +1352,24 @@ void test_nghttp2_hd_deflate_hd_vec(void) {
   vec[0].base = &buf[0];
   vec[0].len = buflen / 2;
   vec[1].base = &buf[buflen / 2];
-  vec[1].len = (buflen / 2) - 1;
+  vec[1].len = (buflen / 2) + 1;
 
   blocklen = nghttp2_hd_deflate_hd_vec(deflater, vec, 2, nva, ARRLEN(nva));
 
-  CU_ASSERT(NGHTTP2_ERR_INVALID_ARGUMENT == blocklen);
+  CU_ASSERT(blocklen > 0);
+
+  nghttp2_bufs_wrap_init(&bufs, buf, (size_t)blocklen, mem);
+  bufs.head->buf.last += blocklen;
+
+  CU_ASSERT(blocklen == inflate_hd(inflater, &out, &bufs, 0, mem));
+  CU_ASSERT(ARRLEN(nva) == out.nvlen);
+  assert_nv_equal(nva, out.nva, ARRLEN(nva), mem);
+
+  nghttp2_bufs_wrap_free(&bufs);
 
   nghttp2_hd_inflate_del(inflater);
   nghttp2_hd_deflate_del(deflater);
+  nva_out_reset(&out, mem);
 
   /* check the case where chunk size is 1 */
   nghttp2_hd_deflate_new(&deflater, 4096);