feat(lnm): move request data to separate buffer if read buffer changes

lnm/include/lnm/http/req.h

@@ -13,24 +13,39 @@
 #define LNM_HTTP_MAX_REQ_HEADERS 32
 #define LNM_HTTP_MAX_REGEX_GROUPS 4
 
+typedef struct lnm_http_req_header {
+  struct {
+    size_t o;
+    size_t len;
+  } name;
+  struct {
+    size_t o;
+    size_t len;
+  } value;
+} lnm_http_req_header;
+
 /**
  * Represents the parsed HTTP request
  */
 typedef struct lnm_http_req {
-  size_t len;
+  struct {
+    char *s;
+    size_t len;
+    bool owned;
+  } buf;
   int minor_version;
   lnm_http_method method;
   struct {
-    const char *s;
+    size_t o;
     size_t len;
     regmatch_t groups[LNM_HTTP_MAX_REGEX_GROUPS];
   } path;
   struct {
-    const char *s;
+    size_t o;
     size_t len;
   } query;
   struct {
-    struct phr_header arr[LNM_HTTP_MAX_REQ_HEADERS];
+    lnm_http_req_header arr[LNM_HTTP_MAX_REQ_HEADERS];
     size_t len;
   } headers;
   struct {
@@ -68,6 +83,9 @@ void lnm_http_req_reset(lnm_http_req *req);
 /**
  * Retrieve a specific header from the request.
  *
+ * Pointers retrieved from this function should never be used between step
+ * functions; simply request the header again if you need to.
+ *
  * @param out where to write pointer to header value
  * @param out_len where to store length of out value
  * @param req request to look for header in
@@ -79,6 +97,9 @@ lnm_err lnm_http_req_header_get(const char **out, size_t *out_len,
 /**
  * Retrieve a specific header from the request by specifying its name.
  *
+ * Pointers retrieved from this function should never be used between step
+ * functions; simply request the header again if you need to.
+ *
  * @param out where to write pointer to header value
  * @param out_len where to store length of out value
  * @param req request to look for header in