feat: assert

gblibc/CMakeLists.txt

@@ -9,6 +9,7 @@ add_library(gblibc STATIC
     src/fcntl.c
     src/unistd.c
     src/wait.c
+    src/assert.c
 )
 
 target_include_directories(gblibc PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include
@@ -17,4 +18,4 @@ target_include_directories(gblibc PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include
 set_target_properties(gblibc PROPERTIES PRIVATE_HEADER
     "private-include/devutil.h,private-include/syscall.h")
 set_target_properties(gblibc PROPERTIES PUBLIC_HEADER
-    "include/stdio.h,include/stdint.h,include/stdarg.h,include/string.h,include/unistd.h,include/sys/types.h,include/sys/wait.h,include/fcntl.h")
+    "include/stdio.h,include/stdint.h,include/stdarg.h,include/string.h,include/unistd.h,include/sys/types.h,include/sys/wait.h,include/fcntl.h,include/assert.h")

gblibc/include/assert.h

@@ -0,0 +1,21 @@
+#ifndef __GBLIBC_ASSERT_H_
+#define __GBLIBC_ASSERT_H_
+
+#ifdef NDEBUG
+#define assert(st) ((void)(st))
+#else
+#define assert(st) ((void)((st) || (__assert_fail(#st, __FILE__, __LINE__, __func__), 0)))
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+_Noreturn void
+__assert_fail(const char* statement, const char* file, int line, const char* func);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

gblibc/src/assert.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include <unistd.h>
+
+_Noreturn void __attribute__((weak))
+__assert_fail(const char* statement, const char* file, int line, const char* func)
+{
+    char buf[256] = {};
+    int len = snprintf(buf, sizeof(buf), "Assertion failed: (%s) in %s:%d, %s\n",
+        statement, file, line, func);
+    write(STDERR_FILENO, buf, len);
+    _exit(-1);
+}