samples: posix: add sample for uname

Add a simple, testable sample to print everything in the utsname struct,
and added a `uname` shell cmd basically copied from nuttx just for fun.

Signed-off-by: Yong Cong Sin <ycsin@meta.com>

samples/posix/uname/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(posix_uname)
+
+target_sources(app PRIVATE src/main.c)

samples/posix/uname/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_POSIX_API=y
+CONFIG_SHELL=y
+CONFIG_SHELL_GETOPT=y

samples/posix/uname/sample.yaml

@@ -0,0 +1,22 @@
+sample:
+  description: posix uname sample
+  name: posix uname
+common:
+  tags: posix
+  filter: not CONFIG_ARCH_POSIX
+  integration_platforms:
+    - native_posix_64
+    - qemu_riscv64
+  harness: console
+  harness_config:
+    type: multi_line
+    ordered: true
+    regex:
+      - "sysname\\[7\\]: Zephyr"
+      - "nodename\\[\\d+\\]: .*"
+      - "release\\[\\d+\\]: \\d+\\.\\d+\\.\\d+"
+      - "version\\[\\d+\\]: .*"
+      - "machine\\[\\d+\\]: .*"
+tests:
+  sample.posix.uname:
+    tags: uname

samples/posix/uname/src/main.c

@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <unistd.h>
+
+#include <sys/utsname.h>
+
+#include <zephyr/kernel.h>
+#include <zephyr/shell/shell.h>
+
+int main(void)
+{
+	struct utsname info;
+
+	uname(&info);
+
+	printk("\nPrinting everything in utsname...\n");
+	printk("sysname[%zu]: %s\n", sizeof(info.sysname), info.sysname);
+	printk("nodename[%zu]: %s\n", sizeof(info.nodename), info.nodename);
+	printk("release[%zu]: %s\n", sizeof(info.release), info.release);
+	printk("version[%zu]: %s\n", sizeof(info.version), info.version);
+	printk("machine[%zu]: %s\n", sizeof(info.machine), info.machine);
+
+	return 0;
+}
+
+#define UNAME_KERNEL   (1 << 0)
+#define UNAME_NODE     (1 << 1)
+#define UNAME_RELEASE  (1 << 2)
+#define UNAME_VERSION  (1 << 3)
+#define UNAME_MACHINE  (1 << 4)
+#define UNAME_PLATFORM (1 << 5)
+#define UNAME_UNKNOWN  (1 << 6)
+#define UNAME_ALL                                                                                  \
+	(UNAME_KERNEL | UNAME_NODE | UNAME_RELEASE | UNAME_VERSION | UNAME_MACHINE | UNAME_PLATFORM)
+void getopt_init(void);
+static int uname_cmd_handler(const struct shell *sh, size_t argc, char **argv)
+{
+	struct utsname info;
+	unsigned int set;
+	int option;
+	bool badarg;
+	bool first;
+	int ret;
+	int i;
+
+	set = 0;
+	badarg = false;
+
+	/* Get the uname options */
+
+	optind = 1;
+	while ((option = getopt(argc, argv, "asonrvmpi")) != -1) {
+		switch (option) {
+		case 'a':
+			set = UNAME_ALL;
+			break;
+
+		case 'o':
+		case 's':
+			set |= UNAME_KERNEL;
+			break;
+
+		case 'n':
+			set |= UNAME_NODE;
+			break;
+
+		case 'r':
+			set |= UNAME_RELEASE;
+			break;
+
+		case 'v':
+			set |= UNAME_VERSION;
+			break;
+
+		case 'm':
+			set |= UNAME_MACHINE;
+			break;
+
+		case 'p':
+			if (set != UNAME_ALL) {
+				set |= UNAME_UNKNOWN;
+			}
+			break;
+
+		case 'i':
+			set |= UNAME_PLATFORM;
+			break;
+
+		case '?':
+		default:
+			badarg = true;
+			break;
+		}
+	}
+
+	/* If a bad argument was encountered, then return without processing the
+	 * command
+	 */
+
+	if (badarg) {
+		struct getopt_state *state = getopt_state_get();
+
+		shell_error(sh, "uname: illegal option -- %c", state->optopt);
+		shell_print(sh, "usage: uname [-asonrvmpi]");
+		return -1;
+	}
+
+	/* If nothing is provided on the command line, the default is -s */
+
+	if (set == 0) {
+		set = UNAME_KERNEL;
+	}
+
+	/* Get uname data */
+
+	ret = uname(&info);
+	if (ret < 0) {
+		shell_error(sh, "uname: returned %d", ret);
+		return -1;
+	}
+
+	/* Process each option */
+
+	first = true;
+	for (i = 0; set != 0; i++) {
+		unsigned int mask = (1 << i);
+
+		if ((set & mask) != 0) {
+			set &= ~mask;
+			switch (i) {
+			case 0: /* print the kernel/operating system name */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", info.sysname);
+				break;
+
+			case 1: /* Print nodename */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", info.nodename);
+				break;
+
+			case 2: /* Print the kernel release */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", info.release);
+				break;
+
+			case 3: /* Print the kernel version */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", info.version);
+				break;
+
+			case 4: /* Print the machine hardware name */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", info.machine);
+				break;
+
+			case 5: /* Print the machine platform name */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", CONFIG_BOARD);
+				break;
+
+			case 6: /* Print "unknown" */
+				shell_fprintf(sh, SHELL_NORMAL, "%s", "unknown");
+				break;
+
+			default:
+				shell_error(sh, "uname: illegal option -- %d", i);
+				return -1;
+			}
+
+			shell_fprintf(sh, SHELL_NORMAL, " ");
+		}
+	}
+
+	shell_fprintf(sh, SHELL_NORMAL, "\n");
+
+	return 0;
+}
+
+SHELL_CMD_REGISTER(uname, NULL, NULL, uname_cmd_handler);