feat: add intentional crash API

CHANGELOG.md

@@ -11,6 +11,7 @@
 - Add `on_crashed_last_run` callback for inspecting crash envelopes from previous runs. ([#1985](https://github.com/getsentry/sentry-native/pull/1985))
 - Add `sentry_get_last_event_id` and `sentry_scope_get_last_event_id` for retrieving the last event ID captured with the global or given scope, respectively. ([#1992](https://github.com/getsentry/sentry-native/pull/1992))
 - Native/Unix: The native crash daemon now loads `libcurl` dynamically at runtime by default when `SENTRY_LINK_CURL=AUTO`, avoiding `libcurl` linker work during process startup and significantly speeding up startup time. Explicitly set `SENTRY_LINK_CURL=ON` to link it directly. ([#1955](https://github.com/getsentry/sentry-native/pull/1955))
+- Add `sentry_crash` for deliberately crashing the current process to test its crash reporting configuration. ([#2013](https://github.com/getsentry/sentry-native/pull/2013))
 - Add missing public scope mutators: `set_release`, `set_environment`, `set_transaction`, `remove_tag`, `remove_extra`, `remove_context`, and `remove_attachment`. ([#2011](https://github.com/getsentry/sentry-native/pull/2011))
 
 **Deprecations**:

examples/example.c

@@ -504,36 +504,6 @@ trigger_fastfail_crash()
 
 #endif
 
-#ifdef SENTRY_PLATFORM_AIX
-// AIX has a null page mapped to the bottom of memory, which means null derefs
-// don't segfault. try dereferencing the top of memory instead; the top nibble
-// seems to be unusable.
-static void *invalid_mem = (void *)0xFFFFFFFFFFFFFF9B; // -100 for memset
-#else
-static void *invalid_mem = (void *)1;
-#endif
-
-// Detect Address Sanitizer (works for both GCC and Clang)
-#if defined(__SANITIZE_ADDRESS__)
-#    define SENTRY_ASAN_ACTIVE 1
-#elif defined(__has_feature)
-#    if __has_feature(address_sanitizer)
-#        define SENTRY_ASAN_ACTIVE 1
-#    endif
-#endif
-
-static void
-trigger_crash()
-{
-#ifdef SENTRY_ASAN_ACTIVE
-    // Under ASAN, raise signal directly to bypass ASAN's memory interception.
-    // ASAN intercepts memset and would abort before our signal handler runs.
-    raise(SIGSEGV);
-#else
-    memset((char *)invalid_mem, 1, 100);
-#endif
-}
-
 static void
 trigger_stack_overflow()
 {
@@ -1313,7 +1283,7 @@ main(int argc, char **argv)
     }
 
     if (has_arg(argc, argv, "crash")) {
-        trigger_crash();
+        sentry_crash();
     }
     if (has_arg(argc, argv, "stack-overflow")) {
         trigger_stack_overflow();
@@ -1522,7 +1492,7 @@ main(int argc, char **argv)
     }
 
     if (has_arg(argc, argv, "crash-after-shutdown")) {
-        trigger_crash();
+        sentry_crash();
     }
 
     return EXIT_SUCCESS;

include/sentry.h

@@ -2520,6 +2520,15 @@ SENTRY_API sentry_uuid_t sentry_capture_minidumpw_n(
 SENTRY_EXPERIMENTAL_API void sentry_handle_exception(
     const sentry_ucontext_t *uctx);
 
+/**
+ * Deliberately crashes the current process.
+ *
+ * This is intended for testing that crash reporting is correctly configured.
+ * To capture the crash, call this only after `sentry_init` returns
+ * successfully.
+ */
+SENTRY_EXPERIMENTAL_API void sentry_crash(void);
+
 /**
  * Type of the `before_breadcrumb` callback.
  *

src/sentry_core.c

@@ -1,5 +1,8 @@
 #include "sentry_boot.h"
 
+#ifndef SENTRY_PLATFORM_PS
+#    include <signal.h>
+#endif
 #include <stdarg.h>
 #include <string.h>
 
@@ -929,6 +932,60 @@ sentry_handle_exception(const sentry_ucontext_t *uctx)
     }
 }
 
+// Detect Address Sanitizer (works for both GCC and Clang)
+#if defined(__SANITIZE_ADDRESS__)
+#    define SENTRY_ASAN_ACTIVE 1
+#elif defined(__has_feature)
+#    if __has_feature(address_sanitizer)
+#        define SENTRY_ASAN_ACTIVE 1
+#    endif
+#endif
+
+// Preserve `sentry_crash` as an unwindable stack frame. Clang's `optnone` is
+// needed on macOS, but on musl it leaves the fault inside stripped `memset`,
+// producing an unsymbolicated stack trace.
+#if defined(_MSC_VER)
+#    define SENTRY_NOINLINE __declspec(noinline)
+#    pragma optimize("", off)
+#elif defined(__has_attribute)
+#    if defined(SENTRY_PLATFORM_MACOS) && __has_attribute(noinline)            \
+        && __has_attribute(optnone)
+#        define SENTRY_NOINLINE __attribute__((noinline, optnone))
+#    elif __has_attribute(noinline) && __has_attribute(optimize)
+#        define SENTRY_NOINLINE __attribute__((noinline, optimize("O0")))
+#    elif __has_attribute(noinline)
+#        define SENTRY_NOINLINE __attribute__((noinline))
+#    endif
+#endif
+#ifndef SENTRY_NOINLINE
+#    define SENTRY_NOINLINE
+#endif
+
+SENTRY_NOINLINE void
+sentry_crash(void)
+{
+#ifdef SENTRY_ASAN_ACTIVE
+    // Under ASAN, raise signal directly to bypass ASAN's memory interception.
+    // ASAN intercepts memset and would abort before our signal handler runs.
+    raise(SIGSEGV);
+#else
+#    ifdef SENTRY_PLATFORM_AIX
+    // AIX has a null page mapped to the bottom of memory, which means null
+    // derefs don't segfault. try dereferencing the top of memory instead; the
+    // top nibble seems to be unusable.
+    void *volatile invalid_mem = (void *)0xFFFFFFFFFFFFFF9B; // -100 for memset
+#    else
+    void *volatile invalid_mem = (void *)1;
+#    endif
+    memset((char *)invalid_mem, 1, 100);
+#endif
+}
+
+#if defined(_MSC_VER)
+#    pragma optimize("", on)
+#endif
+#undef SENTRY_NOINLINE
+
 sentry_uuid_t
 sentry__new_event_id(void)
 {

tests/fixtures/dotnet_signal/Program.cs

@@ -5,8 +5,8 @@ namespace dotnet_signal;
 
 class Program
 {
-    [DllImport("crash", EntryPoint = "native_crash")]
-    static extern void native_crash();
+    [DllImport("sentry", EntryPoint = "sentry_crash")]
+    static extern void sentry_crash();
 
     [DllImport("crash", EntryPoint = "enable_sigaltstack")]
     static extern void enable_sigaltstack();
@@ -72,7 +72,7 @@ public static void RunTest(string[] args, string? databasePath = null)
 
         if (args.Contains("native-crash"))
         {
-            native_crash();
+            sentry_crash();
         }
         else if (args.Contains("managed-exception"))
         {

tests/fixtures/dotnet_signal/crash.c

@@ -1,9 +1,5 @@
 #include <signal.h>
 #include <stdlib.h>
-void native_crash(void)
-{
-    *(int *)10 = 100;
-}
 
 void enable_sigaltstack(void)
 {

tests/fixtures/inproc_stress/concurrent_crash.c

@@ -5,9 +5,10 @@
  * race conditions in the signal handler / handler thread synchronization.
  */
 
+#include <sentry.h>
+
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 
 #ifndef _WIN32
 #    include <pthread.h>
@@ -21,8 +22,6 @@
 
 #define CRASH_THREADS 20
 
-static void *invalid_mem = (void *)1;
-
 // Barrier for synchronizing threads
 #ifndef _WIN32
 static volatile int g_barrier = 0;
@@ -40,7 +39,7 @@ __declspec(noinline)
 void
 do_crash(void)
 {
-    memset((char *)invalid_mem, 1, 100);
+    sentry_crash();
 }
 
 static void

tests/fixtures/inproc_stress/main.c

@@ -270,12 +270,6 @@ test_concurrent_crash(PATH_TYPE database_path)
     return 1;
 }
 
-static void
-trigger_crash(void)
-{
-    memset((char *)invalid_mem, 1, 100);
-}
-
 static int
 setup_sentry_with_crashing_on_crash(PATH_TYPE database_path)
 {
@@ -330,7 +324,7 @@ test_handler_thread_crash(PATH_TYPE database_path)
     // This will crash, trigger the handler thread, which will call
     // on_crash callback, which will crash the handler thread.
     // The fallback should then process in the signal handler.
-    trigger_crash();
+    sentry_crash();
 
     fprintf(stderr, "ERROR: Should have crashed\n");
     sentry_close();
@@ -352,7 +346,7 @@ test_handler_abort_crash(PATH_TYPE database_path)
     // This will crash, trigger the handler thread, which will call
     // on_crash callback, which will call abort(). abort() resets the
     // signal mask, so this tests a different code path.
-    trigger_crash();
+    sentry_crash();
 
     fprintf(stderr, "ERROR: Should have crashed\n");
     sentry_close();
@@ -418,7 +412,7 @@ test_simple_crash(PATH_TYPE database_path)
     fprintf(stderr, "Starting simple crash test\n");
     fflush(stderr);
 
-    trigger_crash();
+    sentry_crash();
 
     fprintf(stderr, "ERROR: Should have crashed\n");
     sentry_close();

tests/fixtures/screenshot/screenshot_win32.c

@@ -4,7 +4,6 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 
 enum {
     IDT_TIMER_CRASH = 1,
@@ -23,14 +22,6 @@ has_arg(int argc, LPWSTR *argv, LPCWSTR arg)
     return false;
 }
 
-static void *invalid_mem = (void *)1;
-
-static void
-trigger_crash()
-{
-    memset((char *)invalid_mem, 1, 100);
-}
-
 static void
 trigger_stack_overflow()
 {
@@ -61,7 +52,7 @@ wnd_proc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
     case WM_TIMER:
         switch (wParam) {
         case IDT_TIMER_CRASH:
-            trigger_crash();
+            sentry_crash();
             break;
         case IDT_TIMER_STACK_OVERFLOW:
             trigger_stack_overflow();