sandbox: add getopt support

This adds simple command-line parsing to sandbox. The idea is that it
sets up the state with options provided, and this state can then be
queried later, as needed.

New flags are declared with the SB_CMDLINE_OPT_SHORT helper macro,
pointers are automatically gathered up in a special section, and
then the core code takes care of gathering them up and processing
at runtime.  This way there is no central place where we have to
store a list of flags with ifdefs.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/arch/sandbox/include/asm/getopt.h b/arch/sandbox/include/asm/getopt.h
new file mode 100644
index 0000000000..685883cd3f
--- /dev/null
+++ b/arch/sandbox/include/asm/getopt.h
@@ -0,0 +1,71 @@
+/*
+ * Code for setting up command line flags like `./u-boot --help`
+ *
+ * Copyright (c) 2011 The Chromium OS Authors.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef __SANDBOX_GETOPT_H
+#define __SANDBOX_GETOPT_H
+
+struct sandbox_state;
+
+/*
+ * Internal structure for storing details about the flag.
+ * Most people should not have to dig around in this as
+ * it only gets parsed by the core sandbox code.  End
+ * consumer code should focus on the macros below and
+ * the callback function.
+ */
+struct sb_cmdline_option {
+	/* The long flag name: "help" for "--help" */
+	const char *flag;
+	/* The (optional) short flag name: "h" for "-h" */
+	int flag_short;
+	/* The help string shown to the user when processing --help */
+	const char *help;
+	/* Whether this flag takes an argument */
+	int has_arg;
+	/* Callback into the end consumer code with the option */
+	int (*callback)(struct sandbox_state *state, const char *opt);
+};
+
+/*
+ * Internal macro to expand the lower macros into the necessary
+ * magic junk that makes this all work.
+ */
+#define _SB_CMDLINE_OPT(f, s, ha, h) \
+	static struct sb_cmdline_option sb_cmdline_option_##f = { \
+		.flag = #f, \
+		.flag_short = s, \
+		.help = h, \
+		.has_arg = ha, \
+		.callback = sb_cmdline_cb_##f, \
+	}; \
+	/* Ppointer to the struct in a special section for the linker script */ \
+	static __attribute__((section(".u_boot_sandbox_getopt"), used)) \
+		struct sb_cmdline_option *sb_cmdline_option_##f##_ptr = \
+		&sb_cmdline_option_##f
+
+/**
+ * Macros for end code to declare new command line flags.
+ *
+ * @param f   The long flag name e.g. help
+ * @param ha  Does the flag have an argument e.g. 0/1
+ * @param h   The help string displayed when showing --help
+ *
+ * This invocation:
+ *   SB_CMDLINE_OPT(foo, 0, "The foo arg");
+ * Will create a new flag named "--foo" (no short option) that takes
+ * no argument.  If the user specifies "--foo", then the callback func
+ * sb_cmdline_cb_foo() will automatically be called.
+ */
+#define SB_CMDLINE_OPT(f, ha, h) _SB_CMDLINE_OPT(f, 0, ha, h)
+/*
+ * Same as above, but @s is used to specify a short flag e.g.
+ *   SB_CMDLINE_OPT(foo, 'f', 0, "The foo arg");
+ */
+#define SB_CMDLINE_OPT_SHORT(f, s, ha, h) _SB_CMDLINE_OPT(f, s, ha, h)
+
+#endif