lsscsi: new applet

function                                             old     new   delta
lsscsi_main                                            -     326    +326
applet_names                                        2613    2620      +7
applet_main                                         1512    1516      +4
applet_install_loc                                   189     190      +1
packed_usage                                       31566   31560      -6
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 3/1 up/down: 338/-6)            Total: 332 bytes

Signed-off-by: Markus Gothe <nietzsche@lysator.liu.se>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

miscutils/lsscsi.c

@@ -0,0 +1,123 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * lsscsi implementation for busybox
+ *
+ * Copyright (C) 2017 Markus Gothe <nietzsche@lysator.liu.se>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+//config:config LSSCSI
+//config:	bool "lsscsi"
+//config:	default y
+//config:	#select PLATFORM_LINUX
+//config:	help
+//config:	  lsscsi is a utility for displaying information about SCSI buses in the
+//config:	  system and devices connected to them.
+//config:
+//config:	  This version uses sysfs (/sys/bus/scsi/devices) only.
+
+//applet:IF_LSSCSI(APPLET(lsscsi, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_LSSCSI) += lsscsi.o
+
+//usage:#define lsscsi_trivial_usage NOUSAGE_STR
+//usage:#define lsscsi_full_usage ""
+
+#include "libbb.h"
+
+static char *get_line(const char *filename, char *buf, unsigned *bufsize_p)
+{
+	unsigned bufsize = *bufsize_p;
+	ssize_t sz;
+
+	if ((int)(bufsize - 2) <= 0)
+		return buf;
+
+	sz = open_read_close(filename, buf, bufsize - 2);
+	if (sz < 0)
+		sz = 0;
+	buf[sz] = '\0';
+	trim(buf);
+
+	sz = strlen(buf) + 1;
+	bufsize -= sz;
+	buf += sz;
+	buf[0] = '\0';
+
+	*bufsize_p = bufsize;
+	return buf;
+}
+
+int lsscsi_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int lsscsi_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
+{
+	struct dirent *de;
+	DIR *dir;
+
+	xchdir("/sys/bus/scsi/devices");
+
+	dir = xopendir(".");
+	while ((de = readdir(dir)) != NULL) {
+		char buf[256];
+		char *ptr;
+		unsigned bufsize;
+		const char *vendor;
+		const char *type_str;
+		const char *type_name;
+		const char *model;
+		const char *rev;
+		unsigned type;
+
+		if (!isdigit(de->d_name[0]))
+			continue;
+		if (!strchr(de->d_name, ':'))
+			continue;
+		if (chdir(de->d_name) != 0)
+			continue;
+
+		bufsize = sizeof(buf);
+		vendor = buf;
+		ptr = get_line("vendor", buf, &bufsize);
+		type_str = ptr;
+		ptr = get_line("type", ptr, &bufsize);
+		model = ptr;
+		ptr = get_line("model", ptr, &bufsize);
+		rev = ptr;
+		ptr = get_line("rev", ptr, &bufsize);
+
+		printf("[%s]\t", de->d_name);
+
+#define scsi_device_types \
+	"disk\0"    "tape\0"    "printer\0" "process\0" \
+	"worm\0"    "\0"        "scanner\0" "optical\0" \
+	"mediumx\0" "comms\0"   "\0"        "\0"        \
+	"storage\0" "enclosu\0" "sim dsk\0" "opti rd\0" \
+	"bridge\0"  "osd\0"     "adi\0"     "\0"        \
+	"\0"        "\0"        "\0"        "\0"        \
+	"\0"        "\0"        "\0"        "\0"        \
+	"\0"        "\0"        "wlun\0"    "no dev"
+		type = bb_strtou(type_str, NULL, 10);
+		if (errno
+		 || type >= 0x20
+		 || (type_name = nth_string(scsi_device_types, type))[0] == '\0'
+		) {
+			printf("(%s)\t", type_str);
+		} else {
+			printf("%s\t", type_name);
+		}
+
+		printf("%s\t""%s\t""%s\n",
+			vendor,
+			model,
+			rev
+		);
+		/* TODO: also output device column, e.g. "/dev/sdX" */
+
+		xchdir("..");
+	}
+
+	if (ENABLE_FEATURE_CLEAN_UP)
+		closedir(dir);
+
+	return EXIT_SUCCESS;
+}