[core] http_header_hkey_get_lc() for HTTP/2

header field-names are required to be lowercase for HTTP/2
so specialize http_header_hkey_get() as http_header_hkey_get_lc()
for simpler comparison

lowercase field-names in http_headers[], as it does not matter for
buffer_eq_icase_ssn(), which is used with http_headers[] for HTTP/1.x

src/http_header.c

@@ -29,35 +29,35 @@ int8_t http_headers_off[] = {
   -1, -1, -1, -1, 0, 4, 5, 9, 10, 11, 12, -1, 15, 16, 20, 22, 24, 26
 };
 static const keyvlenvalue http_headers[] = {
-  { HTTP_HEADER_HOST,                 CONST_LEN_STR("Host") }
- ,{ HTTP_HEADER_DATE,                 CONST_LEN_STR("Date") }
- ,{ HTTP_HEADER_ETAG,                 CONST_LEN_STR("ETag") }
- ,{ HTTP_HEADER_VARY,                 CONST_LEN_STR("Vary") }
- ,{ HTTP_HEADER_RANGE,                CONST_LEN_STR("Range") }
- ,{ HTTP_HEADER_COOKIE,               CONST_LEN_STR("Cookie") }
- ,{ HTTP_HEADER_EXPECT,               CONST_LEN_STR("Expect") }
- ,{ HTTP_HEADER_STATUS,               CONST_LEN_STR("Status") }
- ,{ HTTP_HEADER_SERVER,               CONST_LEN_STR("Server") }
- ,{ HTTP_HEADER_UPGRADE,              CONST_LEN_STR("Upgrade") }
- ,{ HTTP_HEADER_LOCATION,             CONST_LEN_STR("Location") }
- ,{ HTTP_HEADER_FORWARDED,            CONST_LEN_STR("Forwarded") }
- ,{ HTTP_HEADER_CONNECTION,           CONST_LEN_STR("Connection") }
- ,{ HTTP_HEADER_SET_COOKIE,           CONST_LEN_STR("Set-Cookie") }
- ,{ HTTP_HEADER_USER_AGENT,           CONST_LEN_STR("User-Agent") }
- ,{ HTTP_HEADER_CONTENT_TYPE,         CONST_LEN_STR("Content-Type") }
- ,{ HTTP_HEADER_LAST_MODIFIED,        CONST_LEN_STR("Last-Modified") }
- ,{ HTTP_HEADER_AUTHORIZATION,        CONST_LEN_STR("Authorization") }
- ,{ HTTP_HEADER_IF_NONE_MATCH,        CONST_LEN_STR("If-None-Match") }
- ,{ HTTP_HEADER_CACHE_CONTROL,        CONST_LEN_STR("Cache-Control") }
- ,{ HTTP_HEADER_CONTENT_LENGTH,       CONST_LEN_STR("Content-Length") }
- ,{ HTTP_HEADER_HTTP2_SETTINGS,       CONST_LEN_STR("HTTP2-Settings") }
- ,{ HTTP_HEADER_ACCEPT_ENCODING,      CONST_LEN_STR("Accept-Encoding") }
- ,{ HTTP_HEADER_X_FORWARDED_FOR,      CONST_LEN_STR("X-Forwarded-For") }
- ,{ HTTP_HEADER_CONTENT_ENCODING,     CONST_LEN_STR("Content-Encoding") }
- ,{ HTTP_HEADER_CONTENT_LOCATION,     CONST_LEN_STR("Content-Location") }
- ,{ HTTP_HEADER_IF_MODIFIED_SINCE,    CONST_LEN_STR("If-Modified-Since") }
- ,{ HTTP_HEADER_TRANSFER_ENCODING,    CONST_LEN_STR("Transfer-Encoding") }
- ,{ HTTP_HEADER_X_FORWARDED_PROTO,    CONST_LEN_STR("X-Forwarded-Proto") }
+  { HTTP_HEADER_HOST,                 CONST_LEN_STR("host") }
+ ,{ HTTP_HEADER_DATE,                 CONST_LEN_STR("date") }
+ ,{ HTTP_HEADER_ETAG,                 CONST_LEN_STR("etag") }
+ ,{ HTTP_HEADER_VARY,                 CONST_LEN_STR("vary") }
+ ,{ HTTP_HEADER_RANGE,                CONST_LEN_STR("range") }
+ ,{ HTTP_HEADER_COOKIE,               CONST_LEN_STR("cookie") }
+ ,{ HTTP_HEADER_EXPECT,               CONST_LEN_STR("expect") }
+ ,{ HTTP_HEADER_STATUS,               CONST_LEN_STR("status") }
+ ,{ HTTP_HEADER_SERVER,               CONST_LEN_STR("server") }
+ ,{ HTTP_HEADER_UPGRADE,              CONST_LEN_STR("upgrade") }
+ ,{ HTTP_HEADER_LOCATION,             CONST_LEN_STR("location") }
+ ,{ HTTP_HEADER_FORWARDED,            CONST_LEN_STR("forwarded") }
+ ,{ HTTP_HEADER_CONNECTION,           CONST_LEN_STR("connection") }
+ ,{ HTTP_HEADER_SET_COOKIE,           CONST_LEN_STR("set-cookie") }
+ ,{ HTTP_HEADER_USER_AGENT,           CONST_LEN_STR("user-agent") }
+ ,{ HTTP_HEADER_CONTENT_TYPE,         CONST_LEN_STR("content-type") }
+ ,{ HTTP_HEADER_LAST_MODIFIED,        CONST_LEN_STR("last-modified") }
+ ,{ HTTP_HEADER_AUTHORIZATION,        CONST_LEN_STR("authorization") }
+ ,{ HTTP_HEADER_IF_NONE_MATCH,        CONST_LEN_STR("if-none-match") }
+ ,{ HTTP_HEADER_CACHE_CONTROL,        CONST_LEN_STR("cache-control") }
+ ,{ HTTP_HEADER_CONTENT_LENGTH,       CONST_LEN_STR("content-length") }
+ ,{ HTTP_HEADER_HTTP2_SETTINGS,       CONST_LEN_STR("http2-settings") }
+ ,{ HTTP_HEADER_ACCEPT_ENCODING,      CONST_LEN_STR("accept-encoding") }
+ ,{ HTTP_HEADER_X_FORWARDED_FOR,      CONST_LEN_STR("x-forwarded-for") }
+ ,{ HTTP_HEADER_CONTENT_ENCODING,     CONST_LEN_STR("content-encoding") }
+ ,{ HTTP_HEADER_CONTENT_LOCATION,     CONST_LEN_STR("content-location") }
+ ,{ HTTP_HEADER_IF_MODIFIED_SINCE,    CONST_LEN_STR("if-modified-since") }
+ ,{ HTTP_HEADER_TRANSFER_ENCODING,    CONST_LEN_STR("transfer-encoding") }
+ ,{ HTTP_HEADER_X_FORWARDED_PROTO,    CONST_LEN_STR("x-forwarded-proto") }
  ,{ HTTP_HEADER_OTHER, 0, "" }
 };
 
@@ -72,6 +72,17 @@ enum http_header_e http_header_hkey_get(const char * const s, const uint32_t sle
     return HTTP_HEADER_OTHER;
 }
 
+enum http_header_e http_header_hkey_get_lc(const char * const s, const uint32_t slen) {
+    const struct keyvlenvalue * const kv = http_headers;
+    int i = slen < sizeof(http_headers_off) ? http_headers_off[slen] : -1;
+    if (i < 0) return HTTP_HEADER_OTHER;
+    do {
+        if (0 == memcmp(s, kv[i].value, slen))
+            return (enum http_header_e)kv[i].key;
+    } while (slen == kv[++i].vlen);
+    return HTTP_HEADER_OTHER;
+}
+
 
 int http_header_str_to_code (const char * const s)
 {

src/http_header.h

@@ -43,6 +43,8 @@ enum http_header_e {
 
 __attribute_pure__
 enum http_header_e http_header_hkey_get(const char *s, uint32_t slen);
+__attribute_pure__
+enum http_header_e http_header_hkey_get_lc(const char *s, uint32_t slen);
 
 __attribute_pure__
 int http_header_str_to_code (const char * const s);

src/request.c

@@ -807,7 +807,7 @@ http_request_parse_header (request_st * const restrict r, http_header_parse_ctx
                       "invalid character in header -> 400");
             }
 
-            const enum http_header_e id = http_header_hkey_get(k, klen);
+            const enum http_header_e id = http_header_hkey_get_lc(k, klen);
             return http_request_parse_single_header(r, id, k, klen, v, vlen);
         }
     }