refactor to avoid 'transport' struct

Replace 'transport' struct, which would have to be versioned, with a simple
getter API of `get(key, &ptr)` signature.

agent/csec_metadata.c

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020 New Relic Corporation. All rights reserved.
+ * Copyright 2024 New Relic Corporation. All rights reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
 
@@ -14,24 +14,60 @@
 #include "php_compat.h"
 #include "php_newrelic.h"
 
-int nr_php_csec_get_metadata(nr_php_csec_metadata_t* csec_metadata) {
-  if (NULL == csec_metadata) {
+int nr_php_csec_get_metadata(const nr_php_csec_metadata_key_t key, void** p) {
+  const char* value = NULL;
+
+  if (NULL == p) {
     return -1;
   }
 
   if (NULL == NRPRG(app)) {
     return -2;
   }
 
-  csec_metadata->high_security = NRPRG(app)->info.high_security;
-  csec_metadata->entity_name = nr_strdup(nr_app_get_entity_name(NRPRG(app)));
-  csec_metadata->entity_type = nr_strdup(nr_app_get_entity_type(NRPRG(app)));
-  csec_metadata->entity_guid = nr_strdup(nr_app_get_entity_guid(NRPRG(app)));
-  csec_metadata->host_name = nr_strdup(nr_app_get_host_name(NRPRG(app)));
-  csec_metadata->agent_run_id = nr_strdup(NRPRG(app)->agent_run_id);
-  csec_metadata->account_id = nr_strdup(NRPRG(app)->account_id);
-  csec_metadata->license = nr_strdup(NRPRG(license).value);
-  csec_metadata->plicense = nr_strdup(NRPRG(app)->plicense);
+  switch (key) {
+    case NR_PHP_CSEC_METADATA_HIGH_SECURITY:
+      *p = nr_zalloc(sizeof(int));
+      if (NULL == *p) {
+        return -3;
+      }
+      *((int*)*p) = NRPRG(app)->info.high_security;
+      return 0;
+    case NR_PHP_CSEC_METADATA_ENTITY_NAME:
+      value = nr_app_get_entity_name(NRPRG(app));
+      break;
+    case NR_PHP_CSEC_METADATA_ENTITY_TYPE:
+      value = nr_app_get_entity_type(NRPRG(app));
+      break;
+    case NR_PHP_CSEC_METADATA_ENTITY_GUID:
+      value = nr_app_get_entity_guid(NRPRG(app));
+      break;
+    case NR_PHP_CSEC_METADATA_HOST_NAME:
+      value = nr_app_get_host_name(NRPRG(app));
+      break;
+    case NR_PHP_CSEC_METADATA_AGENT_RUN_ID:
+      value = NRPRG(app)->agent_run_id;
+      break;
+    case NR_PHP_CSEC_METADATA_ACCOUNT_ID:
+      value = NRPRG(app)->account_id;
+      break;
+    case NR_PHP_CSEC_METADATA_LICENSE:
+      value = NRPRG(license).value;
+      break;
+    case NR_PHP_CSEC_METADATA_PLICENSE:
+      value = NRPRG(app)->plicense;
+      break;
+    default:
+      return -4;
+  }
 
+  if (NULL == value) {
+    return -5;
+  }
+
+  *p = nr_strdup(value);
+  if (NULL == *p) {
+    return -3;
+  }
   return 0;
 }

agent/csec_metadata.h

@@ -1,37 +1,38 @@
 /*
- * Copyright 2020 New Relic Corporation. All rights reserved.
+ * Copyright 2024 New Relic Corporation. All rights reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
 
 #ifndef CSEC_METADATA_H
 #define CSEC_METADATA_H
 
-typedef struct _nr_php_csec_metadata_t {
-  int high_security;  /* Indicates if high security been set locally for this
-                         application */
-  char* license;      /* License key provided */
-  char* plicense;     /* Printable license (abbreviated for security) */
-  char* host_name;    /* Local host name reported to the daemon */
-  char* entity_name;  /* Entity name related to this application */
-  char* entity_type;  /* Entity type */
-  char* account_id;   /* Security : Added for getting account id */
-  char* entity_guid;  /* Entity guid related to this application */
-  char* agent_run_id; /* The collector's agent run ID; assigned from the
-                         New Relic backend */
-} nr_php_csec_metadata_t;
+typedef enum {
+    NR_PHP_CSEC_METADATA_HIGH_SECURITY = 1,
+    NR_PHP_CSEC_METADATA_ENTITY_NAME,
+    NR_PHP_CSEC_METADATA_ENTITY_TYPE,
+    NR_PHP_CSEC_METADATA_ENTITY_GUID,
+    NR_PHP_CSEC_METADATA_HOST_NAME,
+    NR_PHP_CSEC_METADATA_AGENT_RUN_ID,
+    NR_PHP_CSEC_METADATA_ACCOUNT_ID,
+    NR_PHP_CSEC_METADATA_LICENSE,
+    NR_PHP_CSEC_METADATA_PLICENSE
+} nr_php_csec_metadata_key_t;
 
 /*
- * Purpose : Return app meta data by populating nr_php_csec_metadata_t
- *           structure. The caller is responsible for freeing the memory
- *           allocated for the strings in the structure.
+ * Purpose : Copy requested app meta data into allocated *value.
+ *           The caller is responsible for freeing the memory
+ *           allocated.
  *
  * Params  : Pointer to a nr_php_csec_metadata_t structure
  *
  * Returns : 0 for success
  *          -1 for invalid input
  *          -2 for invalid internal state
+ *          -3 for inability to allocate memory
+ *          -4 for invalid metadata key
+ *          -5 for inability to retrieve metadata value
  */
-extern int nr_php_csec_get_metadata(nr_php_csec_metadata_t*);
-typedef int (*nr_php_csec_get_metadata_t)(nr_php_csec_metadata_t*);
+extern int nr_php_csec_get_metadata(const nr_php_csec_metadata_key_t k, void** value);
+typedef int (*nr_php_csec_get_metadata_t)(const nr_php_csec_metadata_key_t k, void** value);
 #define NR_PHP_CSEC_GET_METADATA "nr_php_csec_get_metadata"
 #endif