MINOR: http: implement http_get_scheme

This method can be used to retrieve the scheme part of an uri, with the
suffix '://'. It will be useful to implement scheme-based normalization.

diff --git a/include/haproxy/http.h b/include/haproxy/http.h
index 582a666471c5e4cfd273c5d603ab620e2a8583c6..991eece49387efa6e0b3db031d937f7930ebfdbb 100644 (file)
--- a/include/haproxy/http.h
+++ b/include/haproxy/http.h
@@ -36,6 +36,7 @@ extern const uint8_t http_char_classes[256];
 enum http_meth_t find_http_meth(const char *str, const int len);
 int http_get_status_idx(unsigned int status);
 const char *http_get_reason(unsigned int status);
+struct ist http_get_scheme(const struct ist uri);
 struct ist http_get_authority(const struct ist uri, int no_userinfo);
 struct ist http_get_path(const struct ist uri);
 int http_header_match2(const char *hdr, const char *end,

diff --git a/src/http.c b/src/http.c
index 689069ce149ed3906c228c144c10d1e68b342135..aff27f1c13cde82c0546b0888b777c930da35a0d 100644 (file)
--- a/src/http.c
+++ b/src/http.c
@@ -468,6 +468,56 @@ const char *http_get_reason(unsigned int status)
        }
 }
 
+/* Parse the uri and looks for the scheme. If not found, an empty ist is
+ * returned. Otherwise, the ist pointing to the scheme is returned.
+ */
+struct ist http_get_scheme(const struct ist uri)
+{
+       const char *ptr, *start, *end;
+
+       if (!uri.len)
+               goto not_found;
+
+       ptr = uri.ptr;
+       start = ptr;
+       end = ptr + uri.len;
+
+       /* RFC7230, par. 2.7 :
+        * Request-URI = "*" | absuri | abspath | authority
+        */
+
+       if (*ptr == '*' || *ptr == '/')
+               goto not_found;
+
+       if (isalpha((unsigned char)*ptr)) {
+               /* this is a scheme as described by RFC3986, par. 3.1, or only
+                * an authority (in case of a CONNECT method).
+                */
+               ptr++;
+               /* retrieve the scheme up to the suffix '://'. If the suffix is
+                * not found, this means there is no scheme and it is an
+                * authority-only uri.
+                */
+               while (ptr < end &&
+                      (isalnum((unsigned char)*ptr) || *ptr == '+' || *ptr == '-' || *ptr == '.'))
+                       ptr++;
+               if (ptr == end || *ptr++ != ':')
+                       goto not_found;
+               if (ptr == end || *ptr++ != '/')
+                       goto not_found;
+               if (ptr == end || *ptr++ != '/')
+                       goto not_found;
+       }
+       else {
+               goto not_found;
+       }
+
+       return ist2(start, ptr - start);
+
+ not_found:
+       return IST_NULL;
+}
+
 /* Parse the uri and looks for the authority, between the scheme and the
  * path. if no_userinfo is not zero, the part before the '@' (including it) is
  * skipped. If not found, an empty ist is returned. Otherwise, the ist pointing