Add oc_endpoint_to_string64

Create an oc_string64_t struct with statically allocated buffer that fits an endpoint address to avoid the use of the heap. The new function oc_endpoint_to_string64 converts an oc_endpoint_t to a string address using the oc_string64_t. Currently used internally. --------- Co-authored-by: Daniel Adam <[email protected]>
iotivity · Sep 20, 2023 · 35f679b · 35f679b
1 parent 7b99f87
commit 35f679b
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Showing 19 changed files with 410 additions and 158 deletions.
diff --git a/api/oc_collection.c b/api/oc_collection.c
@@ -20,6 +20,7 @@
 
 #if defined(OC_COLLECTIONS) && defined(OC_SERVER)
 #include "api/oc_collection_internal.h"
+#include "api/oc_endpoint_internal.h"
 #include "api/oc_helpers_internal.h"
 #include "api/oc_link_internal.h"
 #include "api/oc_ri_internal.h"
@@ -715,10 +716,9 @@ collection_encode_links(const oc_collection_t *collection,
         continue;
       }
       oc_rep_object_array_start_item(eps);
-      oc_string_t ep;
-      if (oc_endpoint_to_string(eps, &ep) == 0) {
+      oc_string64_t ep;
+      if (oc_endpoint_to_string64(eps, &ep)) {
         oc_rep_set_text_string_v1(eps, ep, oc_string(ep), oc_string_len(ep));
-        oc_free_string(&ep);
       }
       oc_rep_object_array_end_item(eps);
     }
@@ -856,10 +856,9 @@ oc_handle_collection_linked_list_request(oc_request_t *request)
           continue;
         }
         oc_rep_object_array_start_item(eps);
-        oc_string_t ep;
-        if (oc_endpoint_to_string(eps, &ep) == 0) {
+        oc_string64_t ep;
+        if (oc_endpoint_to_string64(eps, &ep)) {
           oc_rep_set_text_string_v1(eps, ep, oc_string(ep), oc_string_len(ep));
-          oc_free_string(&ep);
         }
         oc_rep_object_array_end_item(eps);
       }

diff --git a/api/oc_discovery.c b/api/oc_discovery.c
@@ -18,6 +18,7 @@
 
 #include "api/oc_core_res_internal.h"
 #include "api/oc_discovery_internal.h"
+#include "api/oc_endpoint_internal.h"
 #include "api/oc_resource_internal.h"
 #include "api/oc_ri_internal.h"
 #include "api/oc_server_api_internal.h"
@@ -122,12 +123,11 @@ discovery_encode_endpoint(CborEncoder *eps, const oc_endpoint_t *ep,
                           int latency)
 {
   oc_rep_begin_object(eps, ep);
-  oc_string_t ep_str;
-  if (oc_endpoint_to_string(ep, &ep_str) == 0) {
+  oc_string64_t ep_str;
+  if (oc_endpoint_to_string64(ep, &ep_str)) {
     g_err |= oc_rep_encode_text_string(&ep_map, "ep", OC_CHAR_ARRAY_LEN("ep"));
     g_err |= oc_rep_encode_text_string(&ep_map, oc_string(ep_str),
                                        oc_string_len(ep_str));
-    oc_free_string(&ep_str);
   }
   if (latency > 0) {
     g_err |=
@@ -1058,14 +1058,15 @@ oc_wkcore_discovery_handler(oc_request_t *request,
     oc_string_t uri;
     memset(&uri, 0, sizeof(oc_string_t));
     while (eps != NULL) {
-      if (eps->flags & SECURED) {
-        oc_string_t ep;
-        if (oc_endpoint_to_string(eps, &ep) == 0) {
-          length = clf_add_str_to_buffer(oc_string(ep), oc_string_len(ep));
-          response_length += length;
-          oc_free_string(&ep);
-          break;
-        }
+      if ((eps->flags & SECURED) == 0) {
+        eps = eps->next;
+        continue;
+      }
+      oc_string64_t ep;
+      if (oc_endpoint_to_string64(eps, &ep)) {
+        length = clf_add_str_to_buffer(oc_string(ep), oc_string_len(ep));
+        response_length += length;
+        break;
       }
       eps = eps->next;
     }

diff --git a/api/oc_endpoint.c b/api/oc_endpoint.c
@@ -16,8 +16,9 @@
  *
  ****************************************************************************/
 
+#include "api/oc_endpoint_internal.h"
+#include "api/oc_helpers_internal.h"
 #include "oc_endpoint.h"
-#include "oc_endpoint_internal.h"
 #include "oc_core_res.h"
 #include "port/common/oc_ip.h"
 #include "port/oc_connectivity.h"
@@ -66,26 +67,41 @@ oc_endpoint_set_di(oc_endpoint_t *endpoint, const oc_uuid_t *di)
   memcpy(endpoint->di.id, di->id, sizeof(di->id));
 }
 
-const char *
-oc_endpoint_flags_to_scheme(unsigned flags)
+static oc_string_view_t
+endpoint_flags_to_scheme(unsigned flags)
 {
 #ifdef OC_TCP
   if ((flags & TCP) != 0) {
     if ((flags & SECURED) != 0) {
-      return OC_SCHEME_COAPS_TCP;
+      return OC_STRING_VIEW(OC_SCHEME_COAPS_TCP);
     }
-    return OC_SCHEME_COAP_TCP;
+    return OC_STRING_VIEW(OC_SCHEME_COAP_TCP);
   }
-#endif
+#endif /* OC_TCP */
   if ((flags & SECURED) != 0) {
-    return OC_SCHEME_COAPS;
+    return OC_STRING_VIEW(OC_SCHEME_COAPS);
   }
-  return OC_SCHEME_COAP;
+  return OC_STRING_VIEW(OC_SCHEME_COAP);
+}
+
+int
+oc_endpoint_flags_to_scheme(unsigned flags, char *buffer, size_t buffer_size)
+{
+  oc_string_view_t scheme = endpoint_flags_to_scheme(flags);
+  if (buffer == NULL) {
+    return (int)scheme.length;
+  }
+  if (scheme.length < buffer_size) {
+    memcpy(buffer, scheme.data, scheme.length);
+    buffer[scheme.length] = '\0';
+    return (int)scheme.length;
+  }
+  return -1;
 }
 
 int
 oc_endpoint_host(const oc_endpoint_t *endpoint, char *buffer,
-                 uint32_t buffer_size)
+                 size_t buffer_size)
 {
 #ifdef OC_IPV4
   if ((endpoint->flags & IPV4) != 0) {
@@ -99,8 +115,8 @@ oc_endpoint_host(const oc_endpoint_t *endpoint, char *buffer,
 }
 
 int
-oc_endpoint_to_cstring(const oc_endpoint_t *endpoint, char *buffer,
-                       uint32_t buffer_size)
+oc_endpoint_address_and_port_to_cstring(const oc_endpoint_t *endpoint,
+                                        char *buffer, size_t buffer_size)
 {
 #ifdef OC_IPV4
   if ((endpoint->flags & IPV4) != 0) {
@@ -115,22 +131,58 @@ oc_endpoint_to_cstring(const oc_endpoint_t *endpoint, char *buffer,
   return -1;
 }
 
+int
+oc_endpoint_to_cstring(const oc_endpoint_t *endpoint, char *buffer,
+                       size_t buffer_size)
+{
+  int written =
+    oc_endpoint_flags_to_scheme(endpoint->flags, buffer, buffer_size);
+  if (written < 0) {
+    return -1;
+  }
+  int len = written;
+  buffer += written;
+  buffer_size -= (size_t)written;
+  written =
+    oc_endpoint_address_and_port_to_cstring(endpoint, buffer, buffer_size);
+  if (written < 0) {
+    return -1;
+  }
+  return len + written;
+}
+
 int
 oc_endpoint_to_string(const oc_endpoint_t *endpoint, oc_string_t *endpoint_str)
 {
   if (!endpoint || !endpoint_str) {
     return -1;
   }
 
-  char ip[OC_IPV6_MAXSTRLEN] = { 0 };
-  if (oc_endpoint_to_cstring(endpoint, ip, OC_ARRAY_SIZE(ip)) != 0) {
+  oc_string64_t ep_str;
+  if (!oc_endpoint_to_string64(endpoint, &ep_str)) {
     return -1;
   }
-  oc_concat_strings(endpoint_str, oc_endpoint_flags_to_scheme(endpoint->flags),
-                    ip);
+  oc_new_string(endpoint_str, oc_string(ep_str), oc_string_len(ep_str));
   return 0;
 }
 
+bool
+oc_endpoint_to_string64(const oc_endpoint_t *endpoint,
+                        oc_string64_t *endpoint_str)
+{
+  if (!endpoint || !endpoint_str) {
+    return false;
+  }
+  memset(endpoint_str, 0, sizeof(oc_string64_t));
+  int written = oc_endpoint_to_cstring(endpoint, oc_string(*endpoint_str),
+                                       OC_ARRAY_SIZE(endpoint_str->ptr));
+  if (written < 0) {
+    return false;
+  }
+  endpoint_str->size = (size_t)written + 1;
+  return true;
+}
+
 int
 oc_endpoint_port(const oc_endpoint_t *endpoint)
 {
@@ -353,26 +405,8 @@ parse_endpoint_uri(const oc_string_t *endpoint_str,
     return false;
   }
 
-  const char *address = NULL;
-  switch (flags) {
-#ifdef OC_TCP
-  case TCP | SECURED:
-    address = ep + OC_CHAR_ARRAY_LEN(OC_SCHEME_COAPS_TCP);
-    break;
-  case TCP:
-    address = ep + OC_CHAR_ARRAY_LEN(OC_SCHEME_COAP_TCP);
-    break;
-#endif /* OC_TCP */
-  case SECURED:
-    address = ep + OC_CHAR_ARRAY_LEN(OC_SCHEME_COAPS);
-    break;
-  case 0:
-    address = ep + OC_CHAR_ARRAY_LEN(OC_SCHEME_COAP);
-    break;
-  default:
-    OC_ERR("invalid endpoint(%s) uri scheme: %d", ep != NULL ? ep : "", flags);
-    return false;
-  }
+  oc_string_view_t scheme = endpoint_flags_to_scheme(flags);
+  const char *address = ep + scheme.length;
   size_t ep_len = oc_string_len(*endpoint_str);
   size_t address_len = ep_len - (address - ep);
 
@@ -701,12 +735,7 @@ oc_endpoint_list_copy(oc_endpoint_t **dst, const oc_endpoint_t *src)
   return count;
 
 oc_endpoint_list_copy_err:
-  ep = head;
-  while (ep != NULL) {
-    oc_endpoint_t *next = ep->next;
-    oc_free_endpoint(ep);
-    ep = next;
-  }
+  oc_endpoint_list_free(head);
   return -1;
 }
 

diff --git a/api/oc_endpoint_internal.h b/api/oc_endpoint_internal.h
@@ -21,8 +21,11 @@
 
 #include "oc_endpoint.h"
 #include "util/oc_compiler.h"
+#include "util/oc_macros_internal.h"
 
 #include <stdint.h>
+#include <stdbool.h>
+#include <stddef.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -40,28 +43,60 @@ extern "C" {
 
 #define OC_SCHEME_OCF "ocf://"
 
-/** @brief Get scheme string for transport flags */
-const char *oc_endpoint_flags_to_scheme(unsigned flags) OC_RETURNS_NONNULL;
+/**
+ * @brief Write the scheme string (including NUL terminator) for given transport
+ * flags to buffer
+ *
+ * @param flags transport flags of an endpoint
+ * @param buffer output buffer (if NULL the function returns the number of bytes
+ * that would have been written, excluding the NUL terminator)
+ * @param buffer_size size of output buffer
+ * @return return number of written bytes (excluding the NUL terminator)
+ * @return -1 for error
+ */
+int oc_endpoint_flags_to_scheme(unsigned flags, char *buffer,
+                                size_t buffer_size);
 
 /**
  * @brief Convert the endpoint to a human readable string (e.g.
- * "coaps://[fe::22]:/")
+ * "[fe::22]:1234")
  *
- * @param endpoint the endpoint
- * @param buffer output buffer
+ * @param endpoint the endpoint (cannot be NULL)
+ * @param buffer output buffer (cannot be NULL)
  * @param buffer_size size of output buffer
- * @return int 0 success
+ * @return number of written bytes, -1 for error
  */
-int oc_endpoint_to_cstring(const oc_endpoint_t *endpoint, char *buffer,
-                           uint32_t buffer_size) OC_NONNULL();
+int oc_endpoint_address_and_port_to_cstring(const oc_endpoint_t *endpoint,
+                                            char *buffer, size_t buffer_size)
+  OC_NONNULL();
 
 /** @brief Get host of the endpoint as string */
 int oc_endpoint_host(const oc_endpoint_t *endpoint, char *buffer,
-                     uint32_t buffer_size) OC_NONNULL();
+                     size_t buffer_size) OC_NONNULL();
 
 /** @brief Get port of the endpoint */
 int oc_endpoint_port(const oc_endpoint_t *endpoint) OC_NONNULL();
 
+typedef struct oc_string64_s
+{
+  size_t size;
+  char ptr[64];
+} oc_string64_t;
+
+#define oc_string64_cap(ocstring)                                              \
+  (OC_ARRAY_SIZE((ocstring).ptr) - (ocstring).size)
+
+/**
+ * @brief convert the endpoint to a human readable string (e.g.
+ * "coaps://[fe::22]:1234").
+ *
+ * @param endpoint the endpoint
+ * @param endpoint_str endpoint as human readable string
+ * @return true for success
+ */
+bool oc_endpoint_to_string64(const oc_endpoint_t *endpoint,
+                             oc_string64_t *endpoint_str);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/api/oc_introspection.c b/api/oc_introspection.c
@@ -21,6 +21,7 @@
 #ifdef OC_INTROSPECTION
 
 #include "api/oc_core_res_internal.h"
+#include "api/oc_endpoint_internal.h"
 #include "api/oc_introspection_internal.h"
 #include "api/oc_ri_internal.h"
 #include "api/oc_server_api_internal.h"
@@ -126,10 +127,9 @@ oc_introspection_wk_get_uri(size_t device, int interface_index,
     if ((interface_index == -1 ||
          eps->interface_index == (unsigned)interface_index) &&
         (eps->flags == flags)) {
-      oc_string_t ep;
-      if (oc_endpoint_to_string(eps, &ep) == 0) {
+      oc_string64_t ep;
+      if (oc_endpoint_to_string64(eps, &ep)) {
         oc_concat_strings(uri, oc_string(ep), OC_INTROSPECTION_DATA_URI);
-        oc_free_string(&ep);
         return true;
       }
     }