1 #include "quiche/spdy/core/http2_header_storage.h"
2
3 #include <cstring>
4
5 #include "quiche/common/platform/api/quiche_logging.h"
6
7 namespace spdy {
8 namespace {
9
10 // Http2HeaderStorage allocates blocks of this size by default.
11 const size_t kDefaultStorageBlockSize = 2048;
12
13 } // namespace
14
Http2HeaderStorage()15 Http2HeaderStorage::Http2HeaderStorage() : arena_(kDefaultStorageBlockSize) {}
16
Write(const absl::string_view s)17 absl::string_view Http2HeaderStorage::Write(const absl::string_view s) {
18 return absl::string_view(arena_.Memdup(s.data(), s.size()), s.size());
19 }
20
Rewind(const absl::string_view s)21 void Http2HeaderStorage::Rewind(const absl::string_view s) {
22 arena_.Free(const_cast<char*>(s.data()), s.size());
23 }
24
WriteFragments(const std::vector<absl::string_view> & fragments,absl::string_view separator)25 absl::string_view Http2HeaderStorage::WriteFragments(
26 const std::vector<absl::string_view>& fragments,
27 absl::string_view separator) {
28 if (fragments.empty()) {
29 return absl::string_view();
30 }
31 size_t total_size = separator.size() * (fragments.size() - 1);
32 for (const absl::string_view& fragment : fragments) {
33 total_size += fragment.size();
34 }
35 char* dst = arena_.Alloc(total_size);
36 size_t written = Join(dst, fragments, separator);
37 QUICHE_DCHECK_EQ(written, total_size);
38 return absl::string_view(dst, total_size);
39 }
40
Join(char * dst,const std::vector<absl::string_view> & fragments,absl::string_view separator)41 size_t Join(char* dst, const std::vector<absl::string_view>& fragments,
42 absl::string_view separator) {
43 if (fragments.empty()) {
44 return 0;
45 }
46 auto* original_dst = dst;
47 auto it = fragments.begin();
48 memcpy(dst, it->data(), it->size());
49 dst += it->size();
50 for (++it; it != fragments.end(); ++it) {
51 memcpy(dst, separator.data(), separator.size());
52 dst += separator.size();
53 memcpy(dst, it->data(), it->size());
54 dst += it->size();
55 }
56 return dst - original_dst;
57 }
58
59 } // namespace spdy
60