baremetal: build userland/ programs using baremetal path property instead of symlinks

Otherwise I'll go crazy with symlink action.

README.adoc

@@ -1206,35 +1206,6 @@ The terminal prints:
 hello
 ....
 
-Now let's run link:baremetal/arch/aarch64/add.S[]:
-
-....
-./run --arch aarch64 --baremetal baremetal/arch/aarch64/add.S
-....
-
-This time, the terminal does not print anything, which indicates success.
-
-If you look into the source, you will see that we just have an assertion there.
-
-You can see a sample assertion fail in link:baremetal/interactive/assert_fail.c[]:
-
-....
-./run --arch aarch64 --baremetal baremetal/interactive/assert_fail.c
-....
-
-and the terminal contains:
-
-....
-lkmc_test_fail
-error: simulation error detected by parsing logs
-....
-
-and the exit status of our script is 1:
-
-....
-echo $?
-....
-
 To modify a baremetal program, simply edit the file, e.g.
 
 ....
@@ -1252,17 +1223,44 @@ and rebuild:
 
 `./build-baremetal` uses crosstool-NG, and so it must be preceded by link:build-crosstool-ng[], which `./build qemu-baremetal` also calls.
 
-Alternatively, for the sake of tab completion, we also accept relative paths inside `baremetal/`, for example the following also work:
+
+Now let's run link:baremetal/arch/aarch64/add.S[]:
 
 ....
-./run --arch aarch64 --baremetal baremetal/c/hello.c
 ./run --arch aarch64 --baremetal baremetal/arch/aarch64/add.S
 ....
 
-Absolute paths however are used as is and must point to the actual executable:
+This time, the terminal does not print anything, which indicates success: if you look into the source, you will see that we just have an assertion there.
+
+You can see a sample assertion fail in link:baremetal/interactive/assert_fail.c[]:
 
 ....
-./run --arch aarch64 --baremetal "$(./getvar --arch aarch64 baremetal_build_dir)/hello.elf"
+./run --arch aarch64 --baremetal userland/c/assert_fail.c
+....
+
+and the terminal contains:
+
+....
+lkmc_test_fail
+error: simulation error detected by parsing logs
+....
+
+and the exit status of our script is 1:
+
+....
+echo $?
+....
+
+As suggested by the above example, several of the <<userland-content,userland examples>> can also be run in baremetal! This is largely due to the <<about-the-baremetal-setup,awesomeness of Newlib>>.
+
+The examples that work include most <<c,C examples>> that don't rely on complicated syscalls such as threads, and almost all the <<userland-assembly>> examples.
+
+The exact list of userland programs that work in baremetal is specified in <<path-properties>> with the `baremetal` property.
+
+You can run all the baremetal examples in one go and check that all assertions passed with:
+
+....
+./test-baremetal --arch aarch64
 ....
 
 To use gem5 instead of QEMU do:
@@ -11554,6 +11552,9 @@ Programs under link:userland/c/[] are examples of link:https://en.wikipedia.org/
 * Standard library
 ** assert.h
 *** link:userland/c/assert_fail.c[]
+** `stdlib.h`
+*** Exit related
+**** link:userland/c/abort.c[]
 
 Userland assembly content is located at: <<userland-assembly>>. It was split from this section basically becase we were hitting the HTML `h6` limit, stupid web :-)
 
@@ -11677,7 +11678,7 @@ Other infrastructure sanity checks that you might want to look into include:
 
 * link:userland/arch/empty.S[]
 * `LKMC_FAIL` tests
-** link:userland/arch/fail.S[]
+** link:userland/arch/lkmc_assert_fail.S[]
 * `LKMC_ASSERT_EQ` tests
 ** link:userland/arch/x86_64/lkmc_assert_eq_fail.S[]
 ** link:userland/arch/arm/lkmc_assert_eq_fail.S[]
@@ -13609,8 +13610,8 @@ info threads
 shows something like:
 
 ....
-* 1    Thread 1 (CPU#0 [running]) mystart
+* 1    Thread 1 (CPU#0 [running]) lkmc_start
-  2    Thread 2 (CPU#1 [halted ]) mystart
+  2    Thread 2 (CPU#1 [halted ]) lkmc_start
 ....
 
 To wake up CPU 1 on QEMU, we must use the Power State Coordination Interface (PSCI) which is documented at: link:https://developer.arm.com/docs/den0022/latest/arm-power-state-coordination-interface-platform-design-document[].

baremetal/arch/aarch64/no_bootloader/gem5_exit.S

@@ -1,5 +1,5 @@
 #include <lkmc/m5ops.h>
 
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     LKMC_M5OPS_EXIT_ASM

baremetal/arch/aarch64/no_bootloader/semihost_exit.S

@@ -1,7 +1,7 @@
 /* https://github.com/cirosantilli/linux-kernel-module-cheat#semihosting */
 
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     mov x1, 0x26
     movk x1, 2, lsl 16
     ldr x2, =semihost_args

baremetal/arch/arm/no_bootloader/gem5_exit.S

@@ -1,3 +1,3 @@
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     mov r0, #0; mov r1, #0; .inst 0xEE000110 | (0x21 << 16);

baremetal/arch/arm/no_bootloader/semihost_exit.S

@@ -1,5 +1,5 @@
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     mov r0, #0x18
     ldr r1, =#0x20026
     svc 0x00123456

baremetal/c/add.c

@@ -1 +0,0 @@
-../../lkmc/c/add.c

baremetal/c/add.py

@@ -1 +0,0 @@
-../../lkmc/c/add.py

baremetal/c/assert_fail.c

@@ -1 +0,0 @@
-../../lkmc/c/assert_fail.c

baremetal/c/hello.c

@@ -1 +0,0 @@
-../../lkmc/c/hello.c

baremetal/c/infinite_loop.c

@@ -1 +0,0 @@
-../../lkmc/c/infinite_loop.c

baremetal/c/stderr.c

@@ -1 +0,0 @@
-../../lkmc/c/stderr.c

baremetal/lib/aarch64.S

@@ -1,7 +1,7 @@
 #include <lkmc.h>
 
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     /* = NEON setup */
     mov x1, #(0x3 << 20)
     msr cpacr_el1, x1
@@ -20,6 +20,7 @@ mystart:
     bl on_exit
 
     /* Run main. */
+    mov x0, 0
     bl main
 
     /* If main returns, exit. */

baremetal/lib/arm.S

@@ -1,7 +1,7 @@
 #include <lkmc.h>
 
-.global mystart
+.global lkmc_start
-mystart:
+lkmc_start:
     /* Prepare the stack for main, mandatory for C code. */
     ldr sp, =stack_top
 
@@ -10,6 +10,7 @@ mystart:
     bl on_exit
 
     /* Run main. */
+    mov r0, 0
     bl main
 
     /* If main returns, exit. */

baremetal/lib/syscalls.c

@@ -5,6 +5,13 @@
 #include <lkmc.h>
 #include <lkmc/m5ops.h>
 
+void lkmc_baremetal_on_exit_callback(int status, void *arg) {
+    (void)arg;
+    if (status != 0) {
+        printf("lkmc_exit_status_%d\n", status);
+    }
+}
+
 enum {
     UART_FR_RXFE = 0x10,
 };

baremetal/link.ld

@@ -1,4 +1,4 @@
-ENTRY(mystart)
+ENTRY(lkmc_start)
 SECTIONS
 {
   .text : {

baremetal/return.c

@@ -1 +0,0 @@
-int main(void) { return 0; }

build-baremetal

@@ -14,6 +14,7 @@ class Main(common.BuildCliFunction):
             description='''\
 Build the baremetal examples with crosstool-NG.
 ''',
+            is_baremetal=True,
             supported_archs=common.consts['crosstool_ng_supported_archs']
         )
         self._add_argument('--ccflags')
@@ -137,7 +138,10 @@ Build the baremetal examples with crosstool-NG.
 
     def setup_one(self):
         self.env['targets'] = self.resolve_targets(
-            self.env['baremetal_source_dir'],
+            [
+                self.env['baremetal_source_dir'],
+                self.env['userland_source_dir']
+            ],
             self.env['targets']
         )
 

build-userland

@@ -15,7 +15,7 @@ class Main(common.BuildCliFunction):
             kwargs['description'] = '''\
 Build our compiled userland examples.
 '''
-        super().__init__(*args, **kwargs)
+        super().__init__(*args, is_userland=True, **kwargs)
         self._add_argument('--ccflags')
         self._add_argument('--force-rebuild')
         self._add_argument('--optimization-level')
@@ -109,7 +109,7 @@ Default: build all examples that have their package dependencies met, e.g.:
 
     def setup_one(self):
         self.env['targets'] = self.resolve_targets(
-            self.env['userland_source_dir'],
+            [self.env['userland_source_dir']],
             self.env['targets']
         )
 

common.py

@@ -162,6 +162,7 @@ class LkmcCliFunction(cli_function.CliFunction):
     def __init__(
         self,
         *args,
+        is_baremetal=False,
         is_userland=False,
         defaults=None,
         supported_archs=None,
@@ -175,7 +176,8 @@ class LkmcCliFunction(cli_function.CliFunction):
         kwargs['extra_config_params'] = os.path.basename(inspect.getfile(self.__class__))
         if defaults is None:
             defaults = {}
-        self._is_userland = is_userland
+        self.is_baremetal = is_baremetal
+        self.is_userland = is_userland
         self._defaults = defaults
         self._is_common = True
         self._common_args = set()
@@ -1035,8 +1037,12 @@ lunch aosp_{}-eng
             self._common_args.add(key)
         super().add_argument(*args, **kwargs)
 
-    def assert_is_subpath(self, subpath, parent):
+    def assert_is_subpath(self, subpath, parents):
-        if not self.is_subpath(subpath, parent):
+        is_subpath = False
+        for parent in parents:
+            if self.is_subpath(subpath, parent):
+                is_subpath = True
+        if not is_subpath:
             raise Exception(
                 'Can only accept targets inside {}, given: {}'.format(
                     parent,
@@ -1204,7 +1210,7 @@ lunch aosp_{}-eng
                                 continue
                             else:
                                 raise Exception('native emulator only supported in if target arch == host arch')
-                        if env['userland'] is None and not self._is_userland:
+                        if env['userland'] is None and not self.is_userland:
                             if real_all_emulators:
                                 continue
                             else:
@@ -1314,7 +1320,7 @@ lunch aosp_{}-eng
     def resolve_executable(
         self,
         in_path,
-        magic_in_dir,
+        magic_in_dirs,
         magic_out_dir,
         executable_ext
     ):
@@ -1331,35 +1337,47 @@ lunch aosp_{}-eng
         '''
         if not self.env['dry_run'] and not os.path.exists(in_path):
             raise Exception('Input path does not exist: ' + in_path)
-        if self.is_subpath(in_path, magic_in_dir):
+        if len(magic_in_dirs) > 1:
-            # Abspath needed to remove the trailing `/.` which makes e.g. rmrf fail.
+            relative_subpath = self.env['root_dir']
-            out = os.path.abspath(os.path.join(
-                magic_out_dir,
-                os.path.relpath(
-                    os.path.splitext(in_path)[0],
-                    magic_in_dir
-                )
-            ))
-            if os.path.isfile(in_path):
-                out += executable_ext
-            return out
         else:
-            return in_path
+            relative_subpath = magic_in_dirs[0]
+        for magic_in_dir in magic_in_dirs:
+            if self.is_subpath(in_path, magic_in_dir):
+                # Abspath needed to remove the trailing `/.` which makes e.g. rmrf fail.
+                out = os.path.abspath(os.path.join(
+                    magic_out_dir,
+                    os.path.relpath(
+                        os.path.splitext(in_path)[0],
+                        relative_subpath
+                    )
+                ))
+                if os.path.isfile(in_path):
+                    out += executable_ext
+                return out
+        return in_path
 
-    def resolve_targets(self, source_dir, targets):
+    def resolve_targets(self, source_dirs, targets):
+        '''
+        Resolve userland or baremetal CLI provided targets to final paths.
+
+        Notably converts the toplevel directory into all source directories needed.
+        '''
         if not targets:
-            targets = [source_dir]
+            targets = source_dirs.copy()
         new_targets = []
         for target in targets:
-            target = self.toplevel_to_source_dir(target, source_dir)
+            for resolved_target in self.toplevel_to_source_dirs(target, source_dirs):
-            self.assert_is_subpath(target, source_dir)
+                self.assert_is_subpath(resolved_target, source_dirs)
-            new_targets.append(target)
+                new_targets.append(resolved_target)
         return new_targets
 
     def resolve_baremetal_executable(self, path):
         return self.resolve_executable(
             path,
-            self.env['baremetal_source_dir'],
+            [
+                self.env['baremetal_source_dir'],
+                self.env['userland_source_dir']
+            ],
             self.env['baremetal_build_dir'],
             self.env['baremetal_executable_ext'],
         )
@@ -1367,7 +1385,7 @@ lunch aosp_{}-eng
     def resolve_userland_executable(self, path):
         return self.resolve_executable(
             path,
-            self.env['userland_source_dir'],
+            [self.env['userland_source_dir']],
             self.env['userland_build_dir'],
             self.env['userland_executable_ext'],
         )
@@ -1386,12 +1404,12 @@ lunch aosp_{}-eng
         '''
         pass
 
-    def toplevel_to_source_dir(self, path, source_dir):
+    def toplevel_to_source_dirs(self, path, source_dirs):
         path = os.path.abspath(path)
         if path == self.env['root_dir']:
-            return source_dir
+            return source_dirs
         else:
-            return path
+            return [path]
 
     def timed_main(self):
         '''
@@ -1491,13 +1509,21 @@ https://github.com/cirosantilli/linux-kernel-module-cheat#gem5-debug-build
             dirpath_relative_root,
             in_basename
         ))
-        if my_path_properties.should_be_built(self.env, link):
+        if my_path_properties.should_be_built(
+            self.env,
+            link,
+            is_baremetal=self.is_baremetal,
+            is_userland=self.is_userland
+        ):
             if extra_objs is None:
                 extra_objs= []
             if link:
-                if my_path_properties['extra_objs_lkmc_common']:
+                if self.is_baremetal or my_path_properties['extra_objs_lkmc_common']:
                     extra_objs.extend(extra_objs_lkmc_common)
-                if my_path_properties['extra_objs_baremetal_bootloader']:
+                if (
+                    self.is_baremetal and
+                    not my_path_properties['extra_objs_disable_baremetal_bootloader']
+                ):
                     extra_objs.extend(extra_objs_baremetal_bootloader)
             if self.need_rebuild([in_path] + extra_objs + extra_deps, out_path):
                 cc_flags.extend(my_path_properties['cc_flags'])
@@ -1542,7 +1568,7 @@ https://github.com/cirosantilli/linux-kernel-module-cheat#gem5-debug-build
                                             'cc_flags_after': [],
                                         },
                                     }
-                                    package_key = dirpath_relative_root_components[1]
+                                    package_key = dirpath_relative_root_components[2]
                                     if package_key in packages:
                                         package = packages[package_key]
                                     else:

lkmc.c

@@ -23,7 +23,7 @@ LKMC_ASSERT_EQ_DEFINE(64)
 
 void lkmc_assert_fail(uint32_t line) {
     printf("error: assertion failed at line: %" PRIu32 "\n", line);
-    exit(1);
+    abort();
 }
 
 void lkmc_assert_memcmp(
@@ -56,13 +56,6 @@ void lkmc_assert_memcmp(
     }
 }
 
-void lkmc_baremetal_on_exit_callback(int status, void *arg) {
-    (void)arg;
-    if (status != 0) {
-        printf("lkmc_exit_status_%d\n", status);
-    }
-}
-
 #if defined(__aarch64__)
 #define LKMC_SYSREG_READ_WRITE(type, name) \
     type LKMC_CONCAT(LKMC_CONCAT(LKMC_SYSREG_SYMBOL_PREFIX, name), _read(void)) { \

lkmc.h

@@ -20,7 +20,6 @@ LKMC_ASSERT_EQ_DECLARE(32);
 LKMC_ASSERT_EQ_DECLARE(64);
 void lkmc_assert_fail(uint32_t line);
 void lkmc_assert_memcmp(const void *s1, const void *s2, size_t n, uint32_t line);
-void lkmc_baremetal_on_exit_callback(int status, void *arg);
 #endif
 
 /* Assert that the given branch instruction is taken. */

lkmc/c/add.c

@@ -1,13 +0,0 @@
-#include <assert.h>
-
-int main(void) {
-    int i, j, k;
-    i = 1;
-    /* test-gdb-op1 */
-    j = 2;
-    /* test-gdb-op2 */
-    k = i + j;
-    /* test-gdb-result */
-    if (k != 3)
-        assert(0);
-}

lkmc/c/add.py

@@ -1,9 +0,0 @@
-def test(self):
-    self.sendline('tbreak main')
-    self.sendline('continue')
-    self.continue_to('op1')
-    assert self.get_int('i') == 1
-    self.continue_to('op2')
-    assert self.get_int('j') == 2
-    self.continue_to('result')
-    assert self.get_int('k') == 3

lkmc/c/assert_fail.c

@@ -1,18 +0,0 @@
-/* Let's see what happens when an assert fails.
- *
- * Outcome on Ubuntu 19.04 shows the failure line:
- *
- *     assert_fail.out: /path/to/linux-kernel-module-cheat/userland/c/assert_fail.c:15: main: Assertion `0' failed.
- *
- * and exit status 134 == 128 + 6, which corresponds to SIGABORT (6).
- */
-
-#include <assert.h>
-#include <stdlib.h>
-#include <stdio.h>
-
-int main(void) {
-    assert(0);
-    puts("here");
-    return EXIT_SUCCESS;
-}

lkmc/c/getchar.c

@@ -1,21 +0,0 @@
-/* Get on character from stdin, and then print it back out.
- *
- * Same as getc(stdin).
- *
- * You have to press enter for the character to go through:
- * https://stackoverflow.com/questions/1798511/how-to-avoid-pressing-enter-with-getchar
- *
- * Used at:
- * https://stackoverflow.com/questions/556405/what-do-real-user-and-sys-mean-in-the-output-of-time1/53937376#53937376
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-
-int main(void) {
-    char c;
-    printf("enter a character: ");
-    c = getchar();
-    printf("you entered: %c\n", c);
-    return EXIT_SUCCESS;
-}

lkmc/c/hello.c

@@ -1,9 +0,0 @@
-/* Print hello to stdout ;-) */
-
-#include <stdio.h>
-#include <stdlib.h>
-
-int main(void) {
-    puts("hello");
-    return EXIT_SUCCESS;
-}

lkmc/c/infinite_loop.c

@@ -1,29 +0,0 @@
-/* Loop infinitely. Print an integer whenever a period is reached:
- *
- * ....
- * ./infinite_loop [period]
- * ....
- */
-
-#include <inttypes.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-int main(int argc, char **argv) {
-    uintmax_t i, j, period;
-    if (argc > 1) {
-        period = strtoumax(argv[1], NULL, 10);
-    } else {
-        period = 100000000;
-    }
-    i = 0;
-    j = 0;
-    while (1) {
-        i++;
-        if (i % period == 0) {
-            printf("%ju\n", j);
-            j++;
-        }
-    }
-}

lkmc/c/stderr.c

@@ -1,7 +0,0 @@
-/* Print hello to stderr. */
-
-#include <stdio.h>
-
-int main(void) {
-    fputs("hello\n", stderr);
-}

path_properties.py

@@ -1,14 +1,18 @@
 #!/usr/bin/env python3
 
 import os
+import signal
 
 from shell_helpers import LF
 
 class PathProperties:
     default_c_std = 'c11'
     default_cxx_std = 'c++17'
+    # All new properties must be listed here or else you get an error.
     default_properties = {
         'allowed_archs': None,
+        # Examples that can be built in baremetal.
+        'baremetal': False,
         'c_std': default_c_std,
         'cc_flags': [
             '-Wall', LF,
@@ -29,11 +33,14 @@ class PathProperties:
         'cc_flags_after': ['-lm', LF],
         'cc_pedantic': True,
         'cxx_std': default_cxx_std,
+        'disrupts_system': False,
         # Expected program exit status. When signals are raised, this refers
         # to the native exit status. as reported by Bash #?.
         'exit_status': 0,
         'extra_objs': [],
-        'extra_objs_baremetal_bootloader': False,
+        # Explicitly don't add the baremetal bootloader object which normally gets automatically
+        # added to baremetal examples.
+        'extra_objs_disable_baremetal_bootloader': False,
         # We should get rid of this if we ever properly implement dependency graphs.
         'extra_objs_lkmc_common': False,
         'interactive': False,
@@ -45,10 +52,7 @@ class PathProperties:
         # it only generates intermediate object files. Therefore it
         # should not be run while testing.
         'no_executable': False,
-        # the test receives a signal. We skip those tests for now,
+        'receives_signal': None,
-        # on userland because we are lazy to figure out the exact semantics
-        # of how Python + QEMU + gem5 determine the exit status of signals.
-        'receives_signal': False,
         # The script requires a non-trivial argument to be passed to run properly.
         'requires_argument': False,
         'requires_dynamic_library': False,
@@ -68,6 +72,8 @@ class PathProperties:
         # Aruments added automatically to run when running tests,
         # but not on manual running.
         'test_run_args': {},
+        # Examples that can be built in userland.
+        'userland': False,
     }
 
     '''
@@ -93,7 +99,13 @@ class PathProperties:
     def set_path_components(self, path_components):
         self.path_components = path_components
 
-    def should_be_built(self, env, link=False):
+    def should_be_built(
+        self,
+        env,
+        link=False,
+        is_baremetal=False,
+        is_userland=False,
+    ):
         if len(self.path_components) > 1 and \
                 self.path_components[1] == 'libs' and \
                 not env['package_all'] and \
@@ -105,14 +117,22 @@ class PathProperties:
                 self['allowed_archs'] is None or
                 env['arch'] in self['allowed_archs']
             ) and \
+            (
+                (is_userland  and self['userland'] ) or
+                (is_baremetal and self['baremetal'])
+            ) and \
             not (
                 link and
                 self['no_executable']
             )
 
-    def should_be_tested(self, env):
+    def should_be_tested(self, env, is_baremetal=False, is_userland=False):
         return (
-            self.should_be_built(env) and
+            self.should_be_built(
+                env,
+                is_baremetal=is_baremetal,
+                is_userland=is_userland
+            ) and
             not self['interactive'] and
             not self['more_than_1s'] and
             not self['no_executable'] and
@@ -203,6 +223,7 @@ gnu_extension_properties = {
     'cxx_std': 'gnu++17'
 }
 freestanding_properties = {
+    'baremetal': False,
     'cc_flags': [
         '-ffreestanding', LF,
         '-nostdlib', LF,
@@ -216,8 +237,7 @@ path_properties_tuples = (
     {
         'baremetal': (
             {
-                'extra_objs_baremetal_bootloader': True,
+                'baremetal': True,
-                'extra_objs_lkmc_common': True,
             },
             {
                 'arch': (
@@ -229,7 +249,7 @@ path_properties_tuples = (
                                 'gem5_assert.S': {'requires_m5ops': True},
                                 'multicore.S': {'test_run_args': {'cpus': 2}},
                                 'no_bootloader': (
-                                    {'extra_objs_baremetal_bootloader': False},
+                                    {'extra_objs_disable_baremetal_bootloader': True},
                                     {
                                         'gem5_exit.S': {'requires_m5ops': True},
                                         'semihost_exit.S': {'requires_semihosting': True},
@@ -245,7 +265,7 @@ path_properties_tuples = (
                             {
                                 'multicore.S': {'test_run_args': {'cpus': 2}},
                                 'no_bootloader': (
-                                    {'extra_objs_baremetal_bootloader': False},
+                                    {'extra_objs_disable_baremetal_bootloader': True},
                                     {
                                         'gem5_exit.S': {'requires_m5ops': True},
                                         'semihost_exit.S': {'requires_semihosting': True},
@@ -257,32 +277,22 @@ path_properties_tuples = (
                         )
                     }
                 ),
-                'c': (
-                    {},
-                    {
-                        'assert_fail.c': {'exit_status': 134},
-                        'infinite_loop.c': {'more_than_1s': True},
-                    }
-                ),
-                'exit1.c': {'exit_status': 1},
                 'lib': {'no_executable': True},
                 'getchar.c': {'interactive': True},
-                'return1.c': {'exit_status': 1},
-                'return2.c': {'exit_status': 2},
             }
         ),
+        'lkmc.c': {
+            'baremetal': True,
+            'userland': True,
+        },
         'userland': (
             {
-                'cc_flags': [
+                'userland': True,
-                    '-fopenmp', LF,
-                ],
-                'cc_flags_after': [
-                    '-pthread', LF,
-                ],
             },
             {
                 'arch': (
                     {
+                        'baremetal': True,
                         'extra_objs_lkmc_common': True,
                     },
                     {
@@ -316,11 +326,10 @@ path_properties_tuples = (
                                     },
                                 ),
                                 'freestanding': freestanding_properties,
-                                'lkmc_assert_eq_fail.S': {'exit_status': 1},
+                                'lkmc_assert_eq_fail.S': {'receives_signal': signal.Signals.SIGABRT},
-                                'lkmc_assert_memcmp_fail.S': {'exit_status': 1},
+                                'lkmc_assert_memcmp_fail.S': {'receives_signal': signal.Signals.SIGABRT},
                                 'udf.S': {
-                                    'exit_status': 132,
+                                    'receives_signal': signal.Signals.SIGILL
-                                    'receives_signal': True
                                 },
                             }
                         ),
@@ -335,15 +344,16 @@ path_properties_tuples = (
                                     },
                                 ),
                                 'freestanding': freestanding_properties,
-                                'lkmc_assert_eq_fail.S': {'exit_status': 1},
+                                'lkmc_assert_eq_fail.S': {'receives_signal': signal.Signals.SIGABRT},
-                                'lkmc_assert_memcmp_fail.S': {'exit_status': 1},
+                                'lkmc_assert_memcmp_fail.S': {'receives_signal': signal.Signals.SIGABRT},
                                 'udf.S': {
-                                    'exit_status': 132,
+                                    'receives_signal': signal.Signals.SIGILL
-                                    'receives_signal': True
                                 },
                             }
                         ),
-                        'fail.S': {'exit_status': 1},
+                        'lkmc_assert_fail.S': {
+                            'receives_signal': signal.Signals.SIGABRT,
+                        },
                         'x86_64': (
                             {'allowed_archs': {'x86_64'}},
                             {
@@ -353,31 +363,44 @@ path_properties_tuples = (
                                     {
                                         'freestanding': freestanding_properties,
                                         'ring0.c': {
-                                            'exit_status': 139,
+                                            'receives_signal': signal.Signals.SIGSEGV
-                                            'receives_signal': True
                                         }
                                     }
                                 ),
                                 'freestanding': freestanding_properties,
-                                'lkmc_assert_eq_fail.S': {'exit_status': 1},
+                                'lkmc_assert_eq_fail.S': {'receives_signal': signal.Signals.SIGABRT},
-                                'lkmc_assert_memcmp_fail.S': {'exit_status': 1},
+                                'lkmc_assert_memcmp_fail.S': {'receives_signal': signal.Signals.SIGABRT},
                             }
                         ),
                     }
                 ),
                 'c': (
-                    {},
                     {
-                        'assert_fail.c': {
+                        'baremetal': True,
-                            'exit_status': 134,
+                    },
-                            'receives_signal': True,
+                    {
+                        'abort.c': {
+                            'receives_signal': signal.Signals.SIGABRT,
                         },
+                        'assert_fail.c': {
+                            'receives_signal': signal.Signals.SIGABRT,
+                        },
+                        'exit1.c': {'exit_status': 1},
+                        'exit2.c': {'exit_status': 2},
                         'false.c': {'exit_status': 1},
                         'getchar.c': {'interactive': True},
                         'infinite_loop.c': {'more_than_1s': True},
+                        'out_of_memory.c': {'disrupts_system': True},
+                        'return1.c': {'exit_status': 1},
+                        'return2.c': {'exit_status': 2},
+                    }
+                ),
+                'gcc': (
+                    gnu_extension_properties,
+                    {
+                        'openmp.c': {'cc_flags': ['-fopenmp', LF]},
                     }
                 ),
-                'gcc': gnu_extension_properties,
                 'kernel_modules': {**gnu_extension_properties, **{'requires_kernel_modules': True}},
                 'libs': (
                     {'requires_dynamic_library': True},
@@ -398,8 +421,9 @@ path_properties_tuples = (
                         'proc_events.c': {'requires_sudo': True},
                         'sched_getaffinity.c': {'requires_syscall_getcpu': True},
                         'sched_getaffinity_threads.c': {
-                            'requires_syscall_getcpu': True,
+                            'cc_flags_after': ['-pthread', LF],
                             'more_than_1s': True,
+                            'requires_syscall_getcpu': True,
                         },
                         'time_boot.c': {'requires_sudo': True},
                         'virt_to_phys_user.c': {'requires_argument': True},

test-baremetal

@@ -11,6 +11,7 @@ import thread_pool
 class Main(common.TestCliFunction):
     def __init__(self):
         super().__init__(
+            is_baremetal=True,
             supported_archs=common.consts['crosstool_ng_supported_archs'],
         )
         self.add_argument(
@@ -23,7 +24,10 @@ If given, run only the given tests. Otherwise, run all tests.
 
     def setup_one(self):
         self.env['tests'] = self.resolve_targets(
-            self.env['baremetal_source_dir'],
+            [
+                self.env['baremetal_source_dir'],
+                self.env['userland_source_dir']
+            ],
             self.env['tests']
         )
 
@@ -45,7 +49,7 @@ If given, run only the given tests. Otherwise, run all tests.
                         if os.path.splitext(in_filename)[1] in (self.env['c_ext'], self.env['asm_ext']):
                             path_relative_root = os.path.join(dirpath_relative_root, in_filename)
                             my_path_properties = path_properties.get(path_relative_root)
-                            if my_path_properties.should_be_tested(self.env):
+                            if my_path_properties.should_be_tested(self.env, is_baremetal=True):
                                 cur_run_args = run_args.copy()
                                 cur_run_args.update({
                                     'baremetal': os.path.relpath(os.path.join(path_abs, in_filename), os.getcwd()),

test-user-mode

@@ -28,7 +28,7 @@ If given, run only the given tests. Otherwise, run all tests.
 
     def setup_one(self):
         self.env['tests'] = self.resolve_targets(
-            self.env['userland_source_dir'],
+            [self.env['userland_source_dir']],
             self.env['tests']
         )
 
@@ -53,7 +53,7 @@ If given, run only the given tests. Otherwise, run all tests.
                         if os.path.splitext(in_filename)[1] in self.env['build_in_exts']:
                             path_relative_root = os.path.join(dirpath_relative_root, in_filename)
                             my_path_properties = path_properties.get(path_relative_root)
-                            if my_path_properties.should_be_tested(self.env):
+                            if my_path_properties.should_be_tested(self.env, is_userland=True):
                                 cur_run_args = run_args.copy()
                                 cur_run_args.update({
                                     'userland': os.path.relpath(os.path.join(path_abs, in_filename), os.getcwd()),
@@ -65,8 +65,9 @@ If given, run only the given tests. Otherwise, run all tests.
                                     'run_obj': lkmc.import_path.import_path_main('run'),
                                     'test_id': path_relative_root,
                                 }
-                                if my_path_properties['receives_signal']:
+                                signal = my_path_properties['receives_signal']
-                                    run_test_args['expected_exit_status'] = 128 - my_path_properties['exit_status']
+                                if signal is not None:
+                                    run_test_args['expected_exit_status'] = -signal.value
                                 my_thread_pool.submit(run_test_args)
         return self._handle_thread_pool_errors(my_thread_pool)
 

userland/arch/aarch64/fadd_scalar.S

@@ -18,6 +18,12 @@ LKMC_PROLOGUE
 
     /* Now with a memory stored value. */
 .data
+    /* TODO why is this align required, and why only the in the baremetal toolchain?
+     * Otherwise at edfbe9f0d7e9cc40cffd1c68c7c7c30a47fda2a8 + 1 was failing with:
+     * /path/to/linux-kernel-module-cheat/userland/arch/aarch64/fadd_scalar.S:28:(.text+0x3c): relocation truncated to fit: R_AARCH64_LD_PREL_LO19 against `.data'
+     * /path/to/linux-kernel-module-cheat/userland/arch/aarch64/fadd_scalar.S:28: warning: One possible cause of this error is that the symbol is being referenced in the indicated code as if it had a larger alignment than was declared where it was defined.
+     */
+.align 4
 my_double_0:
     .double 1.5
 my_double_1:

userland/arch/aarch64/pc.S

@@ -74,5 +74,6 @@ pc_relative_ldr:
     LKMC_ASSERT_EQ(x0, =0x123456789ABCDEF0)
 LKMC_EPILOGUE
 .data
+.align 4
 pc_relative_str:
     .quad 0x0000000000000000

userland/c/abort.c

@@ -0,0 +1,34 @@
+/* # abort
+ *
+ * Raise a SIGABRT, an ANSI C signal which by default kills the program.
+ *
+ * ....
+ * man abort
+ * ....
+ *
+ * Bibliography:
+ *
+ * * http://stackoverflow.com/questions/397075/what-is-the-difference-between-exit-and-abort
+ * * http://stackoverflow.com/questions/3676221/when-abort-is-preferred-over-exit
+ *
+ * Differences from exit: does not run regular program teardown:
+ *
+ * * does not call `atexit` function.
+ * * does not call C++ destructors
+ *
+ * `assert()` exits the program with abort.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+void atexit_func() {
+    puts("atexit");
+}
+
+int main(void) {
+    /* Will not get called. */
+    atexit(atexit_func);
+    abort();
+    return EXIT_SUCCESS;
+}

userland/c/add.c

@@ -1 +0,0 @@
-../../lkmc/c/add.c

userland/c/add.c

@@ -0,0 +1,13 @@
+#include <assert.h>
+
+int main(void) {
+    int i, j, k;
+    i = 1;
+    /* test-gdb-op1 */
+    j = 2;
+    /* test-gdb-op2 */
+    k = i + j;
+    /* test-gdb-result */
+    if (k != 3)
+        assert(0);
+}

userland/c/add.py

@@ -1 +0,0 @@
-../../lkmc/c/add.py

userland/c/add.py

@@ -0,0 +1,9 @@
+def test(self):
+    self.sendline('tbreak main')
+    self.sendline('continue')
+    self.continue_to('op1')
+    assert self.get_int('i') == 1
+    self.continue_to('op2')
+    assert self.get_int('j') == 2
+    self.continue_to('result')
+    assert self.get_int('k') == 3

userland/c/assert_fail.c

@@ -1 +0,0 @@
-../../lkmc/c/assert_fail.c

userland/c/assert_fail.c

@@ -0,0 +1,18 @@
+/* Let's see what happens when an assert fails.
+ *
+ * Outcome on Ubuntu 19.04 shows the failure line:
+ *
+ *     assert_fail.out: /path/to/linux-kernel-module-cheat/userland/c/assert_fail.c:15: main: Assertion `0' failed.
+ *
+ * and exit status 134 == 128 + 6, which corresponds to SIGABORT (6).
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+int main(void) {
+    assert(0);
+    puts("here");
+    return EXIT_SUCCESS;
+}

userland/c/exit2.c

@@ -0,0 +1,7 @@
+/* https://github.com/cirosantilli/linux-kernel-module-cheat#magic-failure-string */
+
+#include <stdlib.h>
+
+int main(void) {
+    exit(2);
+}

userland/c/getchar.c

@@ -1 +0,0 @@
-../../lkmc/c/getchar.c

userland/c/getchar.c

@@ -0,0 +1,21 @@
+/* Get on character from stdin, and then print it back out.
+ *
+ * Same as getc(stdin).
+ *
+ * You have to press enter for the character to go through:
+ * https://stackoverflow.com/questions/1798511/how-to-avoid-pressing-enter-with-getchar
+ *
+ * Used at:
+ * https://stackoverflow.com/questions/556405/what-do-real-user-and-sys-mean-in-the-output-of-time1/53937376#53937376
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void) {
+    char c;
+    printf("enter a character: ");
+    c = getchar();
+    printf("you entered: %c\n", c);
+    return EXIT_SUCCESS;
+}

userland/c/hello.c

@@ -1 +0,0 @@
-../../lkmc/c/hello.c

userland/c/hello.c

@@ -0,0 +1,9 @@
+/* Print hello to stdout ;-) */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void) {
+    puts("hello");
+    return EXIT_SUCCESS;
+}

userland/c/infinite_loop.c

@@ -1 +0,0 @@
-../../lkmc/c/infinite_loop.c

userland/c/infinite_loop.c

@@ -0,0 +1,29 @@
+/* Loop infinitely. Print an integer whenever a period is reached:
+ *
+ * ....
+ * ./infinite_loop [period]
+ * ....
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char **argv) {
+    uintmax_t i, j, period;
+    if (argc > 1) {
+        period = strtoumax(argv[1], NULL, 10);
+    } else {
+        period = 100000000;
+    }
+    i = 0;
+    j = 0;
+    while (1) {
+        i++;
+        if (i % period == 0) {
+            printf("%ju\n", j);
+            j++;
+        }
+    }
+}

userland/c/out_of_memory.c

@@ -1,18 +1,18 @@
-/* Test out of memory. */
+/* Let's see how much memory Linux lets us allocate. */
 
 #include <stdio.h>
 #include <stdlib.h>
 
 int main(void) {
     char *ptr = NULL;
-    size_t alloc_size = 1;
+    size_t size = 1;
     while (1) {
-        ptr = realloc(ptr, alloc_size);
+        printf("0x%zx\n", size);
+        ptr = realloc(ptr, size);
         if (ptr == NULL) {
-            puts("out of memory");
             break;
         } else {
-            alloc_size <<= 1;
+            size <<= 1;
         }
     }
 }

userland/c/return0.c

@@ -0,0 +1,6 @@
+/* false.c is a superset of this, this is mainly a sanity check for
+ * baremetal where we don't have CLI arguments yet:
+ * https://github.com/cirosantilli/linux-kernel-module-cheat/issues/67
+ */
+
+int main(void) { return 0; }

userland/c/stderr.c

@@ -1 +0,0 @@
-../../lkmc/c/stderr.c

userland/c/stderr.c

@@ -0,0 +1,7 @@
+/* Print hello to stderr. */
+
+#include <stdio.h>
+
+int main(void) {
+    fputs("hello\n", stderr);
+}