#8: move exit() and _sbrk() here

src/_sbrk.c

@@ -0,0 +1,92 @@
+/*
+ * This file is part of the µOS++ distribution.
+ *   (https://github.com/micro-os-plus/)
+ * Copyright (c) 2015 Liviu Ionescu.
+ *
+ * Permission to use, copy, modify, and/or distribute this software
+ * for any purpose is hereby granted, under the terms of the MIT license.
+ *
+ * If a copy of the license was not distributed with this file, it can
+ * be obtained from https://opensource.org/licenses/MIT/.
+ */
+
+#if (!(defined(__APPLE__) || defined(__linux__) || defined(__unix__))) \
+    || defined(__DOXYGEN__)
+
+// ----------------------------------------------------------------------------
+
+#if defined(MICRO_OS_PLUS_INCLUDE_CONFIG_H)
+#include <micro-os-plus/config.h>
+#endif // MICRO_OS_PLUS_INCLUDE_CONFIG_H
+
+#if defined(MICRO_OS_PLUS_INCLUDE_SBRK)
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <stddef.h>
+
+// ----------------------------------------------------------------------------
+
+void*
+_sbrk (ptrdiff_t incr);
+
+// ----------------------------------------------------------------------------
+
+// The definitions used here should be kept in sync with the
+// stack definitions in the linker script.
+
+extern uint32_t __heap_begin__; // Defined by the linker.
+extern uint32_t __heap_end__; // Defined by the linker.
+
+#if defined(MICRO_OS_PLUS_USE_SEMIHOSTING)
+// Heap limit returned from SYS_HEAPINFO semihosting call.
+char* __heap_limit = (char*)0xCAFEDEAD;
+#endif // MICRO_OS_PLUS_USE_SEMIHOSTING
+
+void*
+_sbrk (ptrdiff_t incr)
+{
+  static char* current_heap_end; // STATIC! Zero after BSS init.
+  char* current_block_address;
+
+  if (current_heap_end == 0)
+    {
+      current_heap_end = (char*)&__heap_begin__;
+    }
+
+  current_block_address = current_heap_end;
+
+  // Need to align heap to word boundary, for efficiency reasons and
+  // to possibly avoid hardware faults.
+  // So we assume that the heap starts on word boundary,
+  // hence make sure we always add a multiple of 4 to it.
+  incr = (incr + 3) & (~3); // align value to 4
+  if ((current_heap_end + incr > (char*)&__heap_end__)
+#if defined(MICRO_OS_PLUS_USE_SEMIHOSTING)
+      // Honour heap limit if it's valid.
+      || (__heap_limit != (char*)0xCAFEDEAD
+          && current_heap_end + incr > __heap_limit)
+#endif // MICRO_OS_PLUS_USE_SEMIHOSTING
+  )
+    {
+      // Some of the libstdc++-v3 tests rely upon detecting 'out of memory'
+      // errors, so DO NOT abort here, but return error.
+
+      errno = ENOMEM; // Heap has overflowed.
+      return (caddr_t)-1;
+    }
+
+  current_heap_end += incr;
+
+  return (caddr_t)current_block_address;
+}
+
+#endif // defined(MICRO_OS_PLUS_INCLUDE_SBRK)
+
+// ----------------------------------------------------------------------------
+
+#endif // !Unix
+
+// ----------------------------------------------------------------------------

src/exit.c

@@ -0,0 +1,136 @@
+/*
+ * This file is part of the µOS++ distribution.
+ *   (https://github.com/micro-os-plus/)
+ * Copyright (c) 2015 Liviu Ionescu.
+ *
+ * Permission to use, copy, modify, and/or distribute this software
+ * for any purpose is hereby granted, under the terms of the MIT license.
+ *
+ * If a copy of the license was not distributed with this file, it can
+ * be obtained from https://opensource.org/licenses/MIT/.
+ */
+
+#if (!(defined(__APPLE__) || defined(__linux__) || defined(__unix__))) \
+    || defined(__DOXYGEN__)
+
+// ----------------------------------------------------------------------------
+
+#if defined(MICRO_OS_PLUS_INCLUDE_CONFIG_H)
+#include <micro-os-plus/config.h>
+#endif // MICRO_OS_PLUS_INCLUDE_CONFIG_H
+
+#include <micro-os-plus/startup/hooks.h>
+#include <micro-os-plus/architecture.h>
+#include <micro-os-plus/diag/trace.h>
+
+#include <stdlib.h>
+#include <stdbool.h>
+
+extern void
+micro_os_plus_run_fini_array (void);
+
+extern void
+__call_exitprocs (int, void*);
+
+// ----------------------------------------------------------------------------
+
+void __attribute__ ((weak, noreturn)) abort (void)
+{
+  trace_puts ("abort(), exiting...");
+
+  _Exit (1);
+  /* NOTREACHED */
+}
+
+// ----------------------------------------------------------------------------
+
+/**
+ * @details
+ * `exit()` does several cleanups before ending the application:
+ *
+ * - calls all application-defined cleanup functions enrolled with `atexit()`;
+ * - files and streams are
+ * cleaned up: any pending output is delivered to the host system, each
+ * open file or stream is closed, and files created by `tmpfile()` are
+ * deleted (wishful thinking, not implemented);
+ * - call the static destructors (in reverse order of constructors)
+ *
+ * When all cleanups are done, `_Exit()` is called to perform
+ * the actual termination.
+ */
+void __attribute__ ((noreturn)) exit (int code)
+{
+  trace_printf ("%s(%d)\n", __func__, code);
+
+  // Call the cleanup functions enrolled with atexit().
+  __call_exitprocs (code, NULL);
+
+  // Run the C++ static destructors.
+  micro_os_plus_run_fini_array ();
+
+  // This should normally be the end of it.
+  _Exit (code);
+
+  // Reset again, in case _Exit() did not kill it.
+  // This normally should not happen, but since it can be
+  // overloaded by the application, better safe than sorry.
+  micro_os_plus_terminate (code);
+
+#if defined(MICRO_OS_PLUS_DEBUG)
+  micro_os_plus_architecture_brk ();
+#endif // defined(MICRO_OS_PLUS_DEBUG)
+  // If it does not want to die, loop.
+  while (true)
+    {
+      micro_os_plus_architecture_wfi ();
+    }
+  /* NOTREACHED */
+}
+
+// ----------------------------------------------------------------------------
+
+#pragma GCC diagnostic push
+//#pragma GCC diagnostic ignored "-Wunused-parameter"
+// arm-none-eabi/include/stdlib.h:202:6: note: '_exit' target declared here
+//  202 | void _Exit (int __status) _ATTRIBUTE ((__noreturn__));
+#pragma GCC diagnostic ignored "-Wmissing-attributes"
+
+// On Release, call the hardware reset procedure.
+// On Debug, use a breakpoint to notify the debugger.
+//
+// It can be redefined by the application, if more functionality
+// is required. For example, when semihosting is used, this
+// function sends the return code to the host.
+
+void __attribute__ ((weak, noreturn)) _Exit (int code)
+{
+  trace_printf ("%s(%d)\n", __func__, code);
+
+  // Print some statistics about memory use.
+  micro_os_plus_terminate_goodbye ();
+
+  // Gracefully terminate the trace session.
+  trace_flush ();
+
+  // Reset hardware or terminate the semihosting session.
+  micro_os_plus_terminate (code);
+
+#if defined(MICRO_OS_PLUS_DEBUG)
+  micro_os_plus_architecture_brk ();
+#endif // defined(MICRO_OS_PLUS_DEBUG)
+  while (true)
+    {
+      micro_os_plus_architecture_wfi ();
+    }
+  /* NOTREACHED */
+}
+
+void __attribute__ ((weak, noreturn, alias ("_Exit"))) _exit (int status);
+
+#pragma GCC diagnostic pop
+
+// ----------------------------------------------------------------------------
+
+#endif // !Unix
+
+// ----------------------------------------------------------------------------