[PATCH 1/2] sandbox: add --command line support

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

For easier non-interactive use of sandbox, let's add support to execute
arbitrary commands from the command line directly.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
Cc: Yann Sionneau <ysionneau@kalrayinc.com>
---
 arch/sandbox/Kconfig     |  1 +
 arch/sandbox/os/common.c | 18 +++++++++++++++++-
 common/Kconfig           |  7 +++++++
 common/startup.c         | 13 ++++++++++++-
 include/shell.h          |  9 +++++++++
 5 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/arch/sandbox/Kconfig b/arch/sandbox/Kconfig
index d82027e75047..52915490ca98 100644
--- a/arch/sandbox/Kconfig
+++ b/arch/sandbox/Kconfig
@@ -20,6 +20,7 @@ config SANDBOX
 	select HAS_DEBUG_LL
 	select ARCH_DMA_DEFAULT_COHERENT
 	select ARCH_WANT_FRAME_POINTERS
+	select BAREBOX_CMDLINE
 	default y
 
 config ARCH_TEXT_BASE
diff --git a/arch/sandbox/os/common.c b/arch/sandbox/os/common.c
index 3446074f99d0..14018b2a63b0 100644
--- a/arch/sandbox/os/common.c
+++ b/arch/sandbox/os/common.c
@@ -492,12 +492,20 @@ static int add_dtb(const char *file)
 	return -1;
 }
 
+static char *cmdline;
+
+const char *barebox_cmdline_get(void)
+{
+	return cmdline;
+}
+
 static void print_usage(const char*);
 
 static struct option long_options[] = {
 	{"help",     0, 0, 'h'},
 	{"malloc",   1, 0, 'm'},
 	{"image",    1, 0, 'i'},
+	{"command",  1, 0, 'c'},
 	{"env",      1, 0, 'e'},
 	{"dtb",      1, 0, 'd'},
 	{"stdout",   1, 0, 'O'},
@@ -508,7 +516,7 @@ static struct option long_options[] = {
 	{0, 0, 0, 0},
 };
 
-static const char optstring[] = "hm:i:e:d:O:I:B:x:y:";
+static const char optstring[] = "hm:i:c:e:d:O:I:B:x:y:";
 
 int main(int argc, char *argv[])
 {
@@ -516,6 +524,7 @@ int main(int argc, char *argv[])
 	int opt, ret, fd, fd2;
 	int malloc_size = CONFIG_MALLOC_SIZE;
 	int fdno = 0, envno = 0, option_index = 0;
+	char *new_cmdline;
 	char *aux;
 
 #ifdef CONFIG_ASAN
@@ -539,6 +548,12 @@ int main(int argc, char *argv[])
 			break;
 		case 'i':
 			break;
+		case 'c':
+			if (asprintf(&new_cmdline, "%s%s\n", cmdline ?: "", optarg) < 0)
+				exit(1);
+			free(cmdline);
+			cmdline = new_cmdline;
+			break;
 		case 'e':
 			break;
 		case 'd':
@@ -669,6 +684,7 @@ static void print_usage(const char *prgname)
 "  -i, --image=<dev>=<file>\n"
 "                       Same as above, the files will show up as\n"
 "                       /dev/<dev>\n"
+"  -c, --command=<cmd>  Run extra command after init scripts\n"
 "  -e, --env=<file>     Map a file with an environment to barebox. With this \n"
 "                       option, files are mapped as /dev/env0 ... /dev/envx\n"
 "                       and thus are used as the default environment.\n"
diff --git a/common/Kconfig b/common/Kconfig
index 859356038386..f2245c464056 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -406,6 +406,13 @@ config SIMPLE_READLINE
 	default y
 	depends on !CMDLINE_EDITING
 
+config BAREBOX_CMDLINE
+	bool
+	help
+	  Support a barebox command line when running virtualized.
+	  The commands are appended onto /cmdline, which is sourced
+	  after sourcing all init scripts.
+
 config CBSIZE
 	int
 	prompt "Buffer size for input from the Console"
diff --git a/common/startup.c b/common/startup.c
index 47b70a7756cb..e8bc90aa7f66 100644
--- a/common/startup.c
+++ b/common/startup.c
@@ -30,6 +30,7 @@
 #include <magicvar.h>
 #include <linux/reboot-mode.h>
 #include <asm/sections.h>
+#include <libfile.h>
 #include <uncompress.h>
 #include <globalvar.h>
 #include <console_countdown.h>
@@ -240,7 +241,7 @@ postcore_initcall(register_autoboot_vars);
 
 static int run_init(void)
 {
-	const char *bmode;
+	const char *bmode, *cmdline;
 	bool env_bin_init_exists;
 	enum autoboot_state autoboot;
 	struct stat s;
@@ -289,6 +290,16 @@ static int run_init(void)
 		globfree(&g);
 	}
 
+	cmdline = barebox_cmdline_get();
+	if (cmdline) {
+		ret = write_file("/cmdline", cmdline, strlen(cmdline));
+		if (ret)
+			return ret;
+
+		console_ctrlc_allow();
+		run_command("source /cmdline");
+	}
+
 	/* source matching script in /env/bmode/ */
 	bmode = reboot_mode_get();
 	if (bmode) {
diff --git a/include/shell.h b/include/shell.h
index 073f18102b45..b399564ff391 100644
--- a/include/shell.h
+++ b/include/shell.h
@@ -19,4 +19,13 @@ static inline char *shell_expand(char *str)
 }
 #endif
 
+#ifdef CONFIG_BAREBOX_CMDLINE
+const char *barebox_cmdline_get(void);
+#else
+static inline const char *barebox_cmdline_get(void)
+{
+	return NULL;
+}
+#endif
+
 #endif /* __SHELL_H__ */
-- 
2.39.5