RDKEMW-22210: Fix coverity issues on xdial

[balav08]

Reason for change: Fixing coverity reported issues.
Test Procedure: Refer ticket.
Risks: Low
Priority: P1
version: minor

[Copilot]

Pull request overview

This PR targets Coverity-reported issues in the xdial server implementation, primarily by adding NULL checks and tightening memory/resource handling in the REST and SSDP paths.

Changes:

• Add NULL-guarding around request payload logging and additional-data URL escaping in the libsoup 3.0 REST POST handler.
• Free an allocated handler path string in the libsoup 2.4 SSDP initialization path to address a resource leak.
• Add a NULL check around gdial_app_state_to_string() usage when building the app state XML response.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
server/libsoup/3.0/gdial-rest.c	Adds Coverity-driven NULL checks and adjusts string initialization in response builder logic.
server/libsoup/2.4/gdial-ssdp.c	Frees dail_ssdp_handler after handler registration to address a reported leak.
server/gdial-app.c	Guards against NULL state string when creating the <state> XML node.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Suppressed comments (3)

server/libsoup/3.0/gdial-rest.c:438

• payload_str is guarded, but the log still uses request_body->length even when request_body->data is NULL. With %.*s, a non-zero length would cause an out-of-bounds read from the empty string (and potentially log unrelated memory). Compute the length only when request_body and request_body->data are present (otherwise use 0).

  // coverity fix : FORWARD_NULL - check for NULL request_body->data before using in log
  const char *payload_str = (request_body && request_body->data) ? request_body->data : "";
  GDIAL_LOGERROR("Starting the app with payload %.*s", (int)request_body->length, payload_str);

server/libsoup/3.0/gdial-rest.c:503

• additional_data_url_safe comes from g_uri_escape_string(), which returns GLib-allocated memory intended to be released with g_free(). Using free() can be incorrect on builds where GLib's allocator differs from libc.

    if (additional_data_url_safe) free(additional_data_url_safe);

server/libsoup/3.0/gdial-rest.c:469

• request_body is treated as nullable in this function (e.g., the earlier if (request_body && request_body->data && request_body->length)), but later request_body->data is accessed unconditionally when setting payload. If request_body is NULL, this will crash before the subsequent if (payload && strlen(payload)) guard runs.

    // coverity fix : FORWARD_NULL - check for NULL before calling g_uri_escape_string
    gchar *additional_data_url_safe = additional_data_url ? g_uri_escape_string(additional_data_url, NULL, FALSE) : NULL;
    GDIAL_LOGINFO("additionalDataUrl = %s, %s", additional_data_url ? additional_data_url : "(null)", additional_data_url_safe ? additional_data_url_safe : "(null)");