Remove unused handler_path from shared memory

cursoragent · cursoragent · commit da213bae2824 · 2026-03-12T16:51:38.000Z
The handler_path field in sentry_crash_context_t was being written to
shared memory by the parent process but was never read by the daemon
process. The daemon only uses the handler_path parameter passed to
sentry__crash_daemon_start().

This change:
- Removes the handler_path field from sentry_crash_context_t, saving
  SENTRY_CRASH_MAX_PATH bytes (4096 on Linux, 260 on Windows)
- Passes options-&gt;handler_path-&gt;path directly to the daemon start
  function instead of storing it in shared memory first
- Updates tests to reflect the simplified behavior

Unlike ca_certs, proxy, and user_agent (which the daemon reads from
shared memory in init_daemon), handler_path is now passed directly
where it's actually needed.
diff --git a/src/backends/native/sentry_crash_context.h b/src/backends/native/sentry_crash_context.h
@@ -284,7 +284,6 @@ typedef struct {
     char ca_certs[SENTRY_CRASH_MAX_PATH]; // CA certificates file path for SSL
     char proxy[SENTRY_CRASH_MAX_PATH]; // HTTP proxy URL
     char user_agent[256]; // User-Agent header for HTTP requests
-    char handler_path[SENTRY_CRASH_MAX_PATH]; // Path to sentry-crash executable
 
     // Minidump output path (filled by daemon)
     char minidump_path[SENTRY_CRASH_MAX_PATH];
diff --git a/src/backends/sentry_backend_native.c b/src/backends/sentry_backend_native.c
@@ -234,18 +234,6 @@ native_backend_startup(
 #endif
     }
 
-    // Store handler path for daemon executable lookup
-    if (options->handler_path) {
-#ifdef _WIN32
-        strncpy_s(ctx->handler_path, sizeof(ctx->handler_path),
-            options->handler_path->path, _TRUNCATE);
-#else
-        strncpy(ctx->handler_path, options->handler_path->path,
-            sizeof(ctx->handler_path) - 1);
-        ctx->handler_path[sizeof(ctx->handler_path) - 1] = '\0';
-#endif
-    }
-
     state->event_path = sentry__path_join_str(run_path, "__sentry-event");
     state->breadcrumb1_path
         = sentry__path_join_str(run_path, "__sentry-breadcrumb1");
@@ -330,9 +318,8 @@ native_backend_startup(
 #else
     // Other platforms: Use out-of-process daemon
     // Pass the notification handles (eventfd/pipe on Unix, events on Windows)
-    // handler_path from crash context (empty string if not set by user)
     const char *daemon_handler_path
-        = ctx->handler_path[0] != '\0' ? ctx->handler_path : NULL;
+        = options->handler_path ? options->handler_path->path : NULL;
 #    if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
     uint64_t tid = (uint64_t)pthread_self();
     state->daemon_pid = sentry__crash_daemon_start(getpid(), tid,
diff --git a/tests/unit/test_native_backend.c b/tests/unit/test_native_backend.c
@@ -357,18 +357,11 @@ SENTRY_TEST(crash_context_transport_fields)
     ctx.user_agent[sizeof(ctx.user_agent) - 1] = '\0';
     TEST_CHECK_STRING_EQUAL(ctx.user_agent, test_ua);
 
-    // Verify handler_path field exists and can hold a typical path
-    const char *test_handler = "/usr/local/bin/sentry-crash";
-    strncpy(ctx.handler_path, test_handler, sizeof(ctx.handler_path) - 1);
-    ctx.handler_path[sizeof(ctx.handler_path) - 1] = '\0';
-    TEST_CHECK_STRING_EQUAL(ctx.handler_path, test_handler);
-
     // Verify fields are zero-initialized when memset to 0
     memset(&ctx, 0, sizeof(ctx));
     TEST_CHECK(ctx.ca_certs[0] == '\0');
     TEST_CHECK(ctx.proxy[0] == '\0');
     TEST_CHECK(ctx.user_agent[0] == '\0');
-    TEST_CHECK(ctx.handler_path[0] == '\0');
 #else
     SKIP_TEST();
 #endif
@@ -425,7 +418,10 @@ SENTRY_TEST(crash_context_options_propagation)
 }
 
 /**
- * Test that handler_path option is propagated to crash context
+ * Test that handler_path option is set correctly in options.
+ * Note: handler_path is now passed directly to the daemon start function
+ * instead of being stored in shared memory, since the daemon never reads
+ * it from shared memory.
  */
 SENTRY_TEST(crash_context_handler_path_propagation)
 {
@@ -435,25 +431,15 @@ SENTRY_TEST(crash_context_handler_path_propagation)
     // Set handler path
     sentry_options_set_handler_path(options, "/opt/sentry/sentry-crash");
 
-    // Simulate what native_backend_startup does
-    sentry_crash_context_t ctx;
-    memset(&ctx, 0, sizeof(ctx));
-
-    if (options->handler_path) {
-        strncpy(ctx.handler_path, options->handler_path->path,
-            sizeof(ctx.handler_path) - 1);
-        ctx.handler_path[sizeof(ctx.handler_path) - 1] = '\0';
-    }
-
-    TEST_CHECK_STRING_EQUAL(ctx.handler_path, "/opt/sentry/sentry-crash");
+    // Verify handler_path option is set correctly
+    TEST_ASSERT(!!options->handler_path);
+    TEST_CHECK_STRING_EQUAL(
+        options->handler_path->path, "/opt/sentry/sentry-crash");
 
-    // Without handler_path set, field should remain empty
+    // Without handler_path set, it should be NULL
     sentry_options_t *options2 = sentry_options_new();
     TEST_ASSERT(!!options2);
-    sentry_crash_context_t ctx2;
-    memset(&ctx2, 0, sizeof(ctx2));
-    // Don't set handler_path - verify it stays empty
-    TEST_CHECK(ctx2.handler_path[0] == '\0');
+    TEST_CHECK(options2->handler_path == NULL);
 
     sentry_options_free(options);
     sentry_options_free(options2);
@@ -481,15 +467,10 @@ SENTRY_TEST(crash_context_null_options)
     if (options->proxy) {
         strncpy(ctx.proxy, options->proxy, sizeof(ctx.proxy) - 1);
     }
-    if (options->handler_path) {
-        strncpy(ctx.handler_path, options->handler_path->path,
-            sizeof(ctx.handler_path) - 1);
-    }
 
     // All should remain empty (zero-initialized)
     TEST_CHECK(ctx.ca_certs[0] == '\0');
     TEST_CHECK(ctx.proxy[0] == '\0');
-    TEST_CHECK(ctx.handler_path[0] == '\0');
 
     sentry_options_free(options);
 #else
