[core] perf: tighten some code in some hot paths

src/buffer.c

@@ -723,7 +723,7 @@ void buffer_copy_string_encoded_cgi_varnames(buffer * const restrict b, const ch
  * replaces non-printable characters with '_'
  */
 
-static void buffer_urldecode_internal(buffer *url, int is_query) {
+static void buffer_urldecode_internal(buffer * const url, const int is_query) {
 	unsigned char high, low;
 	char *src;
 	char *dst;
@@ -735,11 +735,17 @@ static void buffer_urldecode_internal(buffer *url, int is_query) {
 
 	src = (char*) url->ptr;
 
-	while ('\0' != *src) {
-		if ('%' == *src) break;
-		if (is_query && '+' == *src) *src = ' ';
-		src++;
+	if (!is_query) {
+		while ('\0' != *src && '%' != *src) ++src;
+	}
+	else {
+		for (; '\0' != *src && '%' != *src; ++src) {
+			if ('+' == *src) *src = ' ';
+		}
 	}
+
+	if ('\0' == *src) return;
+
 	dst = src;
 
 	while ('\0' != *src) {
@@ -923,23 +929,21 @@ void buffer_path_simplify(buffer *dest, buffer *src)
 	buffer_string_set_length(dest, out - start);
 }
 
-void buffer_to_lower(buffer *b) {
-	size_t i;
-
-	for (i = 0; i < b->used; ++i) {
-		char c = b->ptr[i];
-		if (c >= 'A' && c <= 'Z') b->ptr[i] |= 0x20;
-	}
+void buffer_to_lower(buffer * const b) {
+    char * const s = b->ptr;
+    for (uint32_t i = 0; i < b->used; ++i) {
+        char c = s[i];
+        if (c >= 'A' && c <= 'Z') s[i] |= 0x20;
+    }
 }
 
 
-void buffer_to_upper(buffer *b) {
-	size_t i;
-
-	for (i = 0; i < b->used; ++i) {
-		char c = b->ptr[i];
-		if (c >= 'a' && c <= 'z') b->ptr[i] &= ~0x20;
-	}
+void buffer_to_upper(buffer * const b) {
+    char * const s = b->ptr;
+    for (uint32_t i = 0; i < b->used; ++i) {
+        char c = s[i];
+        if (c >= 'a' && c <= 'z') s[i] &= ~0x20;
+    }
 }
 
 

src/connections.c

@@ -404,16 +404,20 @@ static int connection_handle_write_prepare(request_st * const r) {
 			    r->http_status == 304) {
 				/* no Content-Body, no Content-Length */
 				http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH, CONST_STR_LEN("Content-Length"));
-			} else if (qlen > 0 || r->http_method != HTTP_METHOD_HEAD) {
-				/* qlen = 0 is important for Redirects (301, ...) as they MAY have
-				 * a content. Browsers are waiting for a Content otherwise
-				 */
+			} else if (qlen > 0) {
 				buffer * const tb = r->tmp_buf;
 				buffer_clear(tb);
 				buffer_append_int(tb, qlen);
 				http_header_response_set(r, HTTP_HEADER_CONTENT_LENGTH,
 				                         CONST_STR_LEN("Content-Length"),
 				                         CONST_BUF_LEN(tb));
+			} else if (r->http_method != HTTP_METHOD_HEAD) {
+				/* qlen = 0 is important for Redirects (301, ...) as they MAY have
+				 * a content. Browsers are waiting for a Content otherwise
+				 */
+				http_header_response_set(r, HTTP_HEADER_CONTENT_LENGTH,
+				                         CONST_STR_LEN("Content-Length"),
+				                         CONST_STR_LEN("0"));
 			}
 		}
 	} else {

src/http_header.c

@@ -55,11 +55,10 @@ enum http_header_e http_header_hkey_get(const char * const s, const uint32_t sle
     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;
-    for (; slen == kv[i].vlen; ++i) {
-        if (slen == kv[i].vlen
-            && buffer_eq_icase_ssn(s, kv[i].value, slen))
+    do {
+        if (buffer_eq_icase_ssn(s, kv[i].value, slen))
             return (enum http_header_e)kv[i].key;
-    }
+    } while (slen == kv[++i].vlen);
     return HTTP_HEADER_OTHER;
 }