poc(native): Add Android support for out-of-process crash handling

CMakeLists.txt

@@ -841,6 +841,11 @@ elseif(SENTRY_BACKEND_NATIVE)
 		${PROJECT_SOURCE_DIR}/src
 		${PROJECT_SOURCE_DIR}/src/backends/native
 	)
+	if(SENTRY_WITH_LIBUNWINDSTACK)
+		target_include_directories(sentry-crash PRIVATE
+			${PROJECT_SOURCE_DIR}/external/libunwindstack-ndk/include
+		)
+	endif()
 
 	# Link same libraries as sentry
 	target_link_libraries(sentry-crash PRIVATE ${_SENTRY_PLATFORM_LIBS})

src/CMakeLists.txt

@@ -194,7 +194,7 @@ elseif(SENTRY_BACKEND_NATIVE)
 	target_include_directories(sentry PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/backends/native)
 
 	# Platform-specific libraries for native backend
-	if(LINUX OR ANDROID)
+	if(LINUX AND NOT ANDROID)
 		# Linux needs pthread and rt for shared memory
 		target_link_libraries(sentry PRIVATE pthread rt)
 	elseif(APPLE)

src/backends/native/sentry_crash_daemon.c

@@ -3237,7 +3237,11 @@ daemon_file_logger(
     fflush(log_file); // Flush immediately to ensure logs are written
 }
 
-#if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#if defined(SENTRY_PLATFORM_ANDROID)
+int
+sentry__crash_daemon_main(pid_t app_pid, uint64_t app_tid, int notify_eventfd,
+    int ready_eventfd, int shm_fd)
+#elif defined(SENTRY_PLATFORM_LINUX)
 int
 sentry__crash_daemon_main(
     pid_t app_pid, uint64_t app_tid, int notify_eventfd, int ready_eventfd)
@@ -3253,7 +3257,10 @@ sentry__crash_daemon_main(pid_t app_pid, uint64_t app_tid, HANDLE event_handle,
 {
     // Initialize IPC first (attach to shared memory created by parent)
     // We need this to get the database path for logging
-#if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#if defined(SENTRY_PLATFORM_ANDROID)
+    sentry_crash_ipc_t *ipc = sentry__crash_ipc_init_daemon(
+        app_pid, app_tid, notify_eventfd, ready_eventfd, shm_fd);
+#elif defined(SENTRY_PLATFORM_LINUX)
     sentry_crash_ipc_t *ipc = sentry__crash_ipc_init_daemon(
         app_pid, app_tid, notify_eventfd, ready_eventfd);
 #elif defined(SENTRY_PLATFORM_MACOS)
@@ -3532,7 +3539,11 @@ sentry__crash_daemon_main(pid_t app_pid, uint64_t app_tid, HANDLE event_handle,
     return 0;
 }
 
-#if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#if defined(SENTRY_PLATFORM_ANDROID)
+pid_t
+sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid, int notify_eventfd,
+    int ready_eventfd, int shm_fd, const char *handler_path)
+#elif defined(SENTRY_PLATFORM_LINUX)
 pid_t
 sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid, int notify_eventfd,
     int ready_eventfd, const char *handler_path)
@@ -3653,6 +3664,12 @@ sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid, HANDLE event_handle,
         if (ready_flags != -1) {
             fcntl(ready_eventfd, F_SETFD, ready_flags & ~FD_CLOEXEC);
         }
+#    if defined(SENTRY_PLATFORM_ANDROID)
+        int shm_flags = fcntl(shm_fd, F_GETFD);
+        if (shm_flags != -1) {
+            fcntl(shm_fd, F_SETFD, shm_flags & ~FD_CLOEXEC);
+        }
+#    endif
 
         // Convert arguments to strings for exec
         char pid_str[32], tid_str[32], notify_str[32], ready_str[32];
@@ -3661,8 +3678,15 @@ sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid, HANDLE event_handle,
         snprintf(notify_str, sizeof(notify_str), "%d", notify_eventfd);
         snprintf(ready_str, sizeof(ready_str), "%d", ready_eventfd);
 
+#    if defined(SENTRY_PLATFORM_ANDROID)
+        char shm_str[32];
+        snprintf(shm_str, sizeof(shm_str), "%d", shm_fd);
+        char *argv[] = { "sentry-crash", pid_str, tid_str, notify_str,
+            ready_str, shm_str, NULL };
+#    else
         char *argv[]
             = { "sentry-crash", pid_str, tid_str, notify_str, ready_str, NULL };
+#    endif
 
         if (!sentry__string_empty(handler_path)) {
             execv(handler_path, argv);
@@ -3830,12 +3854,13 @@ main(int argc, char **argv)
 {
     // Expected arguments:
     //   Linux:  <app_pid> <app_tid> <notify_handle> <ready_handle>
-    //   macOS:  <app_pid> <app_tid> <notify_handle> <ready_handle> <shm_fd>
-#    if defined(SENTRY_PLATFORM_MACOS)
+    //   macOS/Android: <app_pid> <app_tid> <notify_handle> <ready_handle>
+    //   <shm_fd>
+#    if defined(SENTRY_PLATFORM_MACOS) || defined(SENTRY_PLATFORM_ANDROID)
     if (argc < 6) {
         fprintf(stderr,
-            "Usage: sentry-crash <app_pid> <app_tid> <notify_pipe> "
-            "<ready_pipe> <shm_fd>\n");
+            "Usage: sentry-crash <app_pid> <app_tid> <notify_handle> "
+            "<ready_handle> <shm_fd>\n");
         return 1;
     }
 #    else
@@ -3851,7 +3876,13 @@ main(int argc, char **argv)
     pid_t app_pid = (pid_t)strtoul(argv[1], NULL, 10);
     uint64_t app_tid = strtoull(argv[2], NULL, 16);
 
-#    if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#    if defined(SENTRY_PLATFORM_ANDROID)
+    int notify_eventfd = atoi(argv[3]);
+    int ready_eventfd = atoi(argv[4]);
+    int shm_fd_arg = atoi(argv[5]);
+    return sentry__crash_daemon_main(
+        app_pid, app_tid, notify_eventfd, ready_eventfd, shm_fd_arg);
+#    elif defined(SENTRY_PLATFORM_LINUX)
     int notify_eventfd = atoi(argv[3]);
     int ready_eventfd = atoi(argv[4]);
     return sentry__crash_daemon_main(

src/backends/native/sentry_crash_daemon.h

@@ -24,7 +24,11 @@ struct sentry_options_s;
  * @param ready_handle Ready signal handle
  * @return Daemon PID on success, -1 on failure
  */
-#if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#if defined(SENTRY_PLATFORM_ANDROID)
+pid_t sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid,
+    int notify_eventfd, int ready_eventfd, int shm_fd,
+    const char *handler_path);
+#elif defined(SENTRY_PLATFORM_LINUX)
 pid_t sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid,
     int notify_eventfd, int ready_eventfd, const char *handler_path);
 #elif defined(SENTRY_PLATFORM_MACOS)
@@ -44,7 +48,10 @@ pid_t sentry__crash_daemon_start(pid_t app_pid, uint64_t app_tid,
  * @param notify_handle Notification handle for crash signals
  * @param ready_handle Ready signal handle to signal parent
  */
-#if defined(SENTRY_PLATFORM_LINUX) || defined(SENTRY_PLATFORM_ANDROID)
+#if defined(SENTRY_PLATFORM_ANDROID)
+int sentry__crash_daemon_main(pid_t app_pid, uint64_t app_tid,
+    int notify_eventfd, int ready_eventfd, int shm_fd);
+#elif defined(SENTRY_PLATFORM_LINUX)
 int sentry__crash_daemon_main(
     pid_t app_pid, uint64_t app_tid, int notify_eventfd, int ready_eventfd);
 #elif defined(SENTRY_PLATFORM_MACOS)

src/backends/native/sentry_crash_handler.c

@@ -693,9 +693,9 @@ crash_signal_handler(int signum, siginfo_t *info, void *context)
     // Dump daemon log for debugging (uses stdio, safe after page allocator
     // enabled)
     // Extract the shm identifier for log path construction
-    // macOS: shm_path = "{tmpdir}/.sentry-shm-{id}", Linux: shm_name =
-    // "/s-{id}"
-#    if defined(SENTRY_PLATFORM_MACOS)
+    // macOS/Android: shm_path = "{tmpdir}/.sentry-shm-{id}", Linux:
+    // shm_name = "/s-{id}"
+#    if defined(SENTRY_PLATFORM_MACOS) || defined(SENTRY_PLATFORM_ANDROID)
     const char *shm_id_src = ipc ? ipc->shm_path : "";
 #    else
     const char *shm_id_src = ipc ? ipc->shm_name : "";