[PATCH v2 01/13] common: introduce structured I/O

[Ahmad Fatoum <a.fatoum@barebox.org>]

Structured I/O is an alternative method for shell commands input and
output. Instead of consuming and producing lines of unstructured
strings, commands receive objects with dedicated attributes.

In the future, once enough commands support this, we could make it
available in the shell as the pipe operator.

Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
v1 -> v2:
  - replace wrong select PARAM with select PARAMETER
---
 common/Kconfig     |  4 ++++
 common/Makefile    |  1 +
 common/structio.c  | 56 ++++++++++++++++++++++++++++++++++++++++++++++
 include/structio.h | 44 ++++++++++++++++++++++++++++++++++++
 4 files changed, 105 insertions(+)
 create mode 100644 common/structio.c
 create mode 100644 include/structio.h

diff --git a/common/Kconfig b/common/Kconfig
index 67aff85efc9b..b32a7cb2960b 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -55,6 +55,10 @@ config BLOCK_STATS
 config FILETYPE
 	bool
 
+config STRUCTIO
+	bool
+	select PARAMETER
+
 config BINFMT
 	bool
 	select FILETYPE
diff --git a/common/Makefile b/common/Makefile
index b50b92122293..7a91ef21f79b 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -2,6 +2,7 @@
 
 obj-y				+= boards/
 obj-y				+= memory.o
+obj-$(CONFIG_STRUCTIO)		+= structio.o
 obj-y				+= memory_display.o
 pbl-$(CONFIG_PBL_CONSOLE)	+= memory_display.o
 obj-y				+= clock.o
diff --git a/common/structio.c b/common/structio.c
new file mode 100644
index 000000000000..935c4628dd77
--- /dev/null
+++ b/common/structio.c
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <structio.h>
+#include <command.h>
+#include <device.h>
+
+static struct bobject *active_capture;
+
+struct bobject *structio_active(void)
+{
+	return active_capture;
+}
+
+int structio_run_command(struct bobject **bret, const char *cmd)
+{
+	struct bobject *bobj;
+	int ret;
+
+	if (!bret)
+		return run_command(cmd);
+
+	active_capture = bobj = bobject_alloc("capture");
+	bobj->local = true;
+
+	ret = run_command(cmd);
+
+	active_capture = NULL;
+
+	if (ret) {
+		bobject_free(bobj);
+		return ret;
+	}
+
+	*bret = bobj;
+	return 0;
+}
+
+int structio_devinfo(struct bobject **bret, struct device *dev)
+{
+	struct bobject *bobj;
+
+	if (!bret) {
+		devinfo(dev);
+		return 0;
+	}
+
+	active_capture = bobj = bobject_alloc("devinfo");
+	bobj->local = true;
+
+	devinfo(dev);
+
+	active_capture = NULL;
+
+	*bret = bobj;
+	return 0;
+}
diff --git a/include/structio.h b/include/structio.h
new file mode 100644
index 000000000000..1c97b4c29b79
--- /dev/null
+++ b/include/structio.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __STRUCTIO_H_
+#define __STRUCTIO_H_
+
+#include <bobject.h>
+
+#ifdef CONFIG_STRUCTIO
+struct bobject *structio_active(void);
+int structio_run_command(struct bobject **, const char *cmd);
+int structio_devinfo(struct bobject **, struct device *dev);
+#else
+#define structio_active() NULL
+static inline int structio_run_command(struct bobject **bobj, const char *cmd)
+{
+	return -ENOSYS;
+}
+
+static inline int structio_devinfo(struct bobject **bobj, struct device *dev)
+{
+	return -ENOSYS;
+}
+#endif
+
+#define stprintf(name, fmt, ...) do { \
+	struct bobject *__bobj = structio_active(); \
+	if (__bobj) \
+		bobject_add_param_fixed(__bobj, name, fmt, ##__VA_ARGS__); \
+	else \
+		printf(name ": " fmt "\n", ##__VA_ARGS__); \
+} while (0)
+
+#define stprintf_prefix(name, prefix, fmt, ...) do { \
+	struct bobject *__bobj = structio_active(); \
+	if (__bobj) \
+		bobject_add_param_fixed(__bobj, name, fmt, ##__VA_ARGS__); \
+	else \
+		printf(prefix fmt "\n", ##__VA_ARGS__); \
+} while (0)
+
+#define stprintf_single(name, fmt...) stprintf_prefix(name, "", fmt)
+
+#define stnoprintf(args...) ({ structio_active() ? 0 : (printf(args), 1); })
+
+#endif
-- 
2.39.5