ubirmvol: Implement -N switch for ubirmvol

function                                             old     new   delta
get_volid_by_name                                      -     125    +125
ubi_devnum_from_devname                                -      43     +43
ubi_tools_main                                      1215    1220      +5
packed_usage                                       30674   30655     -19
ubirename_main                                       394     221    -173
------------------------------------------------------------------------------
(add/remove: 3/0 grow/shrink: 1/2 up/down: 173/-192)          Total: -19 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

4 files changed, 69 insertions, 31 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 64e61cd..35c28df 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1770,6 +1770,9 @@ void bb_progress_update(bb_progress_t *p,
 			uoff_t transferred,
 			uoff_t totalsize) FAST_FUNC;
 
+unsigned ubi_devnum_from_devname(const char *str) FAST_FUNC;
+int get_volid_by_name(unsigned ubi_devnum, const char *vol_name) FAST_FUNC;
+
 
 extern const char *applet_name;
 
diff --git a/libbb/ubi.c b/libbb/ubi.c
new file mode 100644
index 0000000..7d3b295
--- /dev/null
+++ b/libbb/ubi.c
@@ -0,0 +1,43 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2016 Denys Vlasenko
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+//kbuild:lib-y += ubi.o
+
+#include "libbb.h"
+
+// from ubi-media.h
+#define UBI_MAX_VOLUME_NAME 127
+#define UBI_MAX_VOLUMES     128
+
+unsigned FAST_FUNC ubi_devnum_from_devname(const char *str)
+{
+        unsigned ubi_devnum;
+
+        if (sscanf(str, "/dev/ubi%u", &ubi_devnum) != 1)
+                bb_error_msg_and_die("not an UBI device: '%s'", str);
+	return ubi_devnum;
+}
+
+int FAST_FUNC get_volid_by_name(unsigned ubi_devnum, const char *vol_name)
+{
+	unsigned i;
+
+	for (i = 0; i < UBI_MAX_VOLUMES; i++) {
+		char buf[UBI_MAX_VOLUME_NAME + 1];
+		char fname[sizeof("/sys/class/ubi/ubi%u_%u/name") + 2 * sizeof(int)*3];
+
+		sprintf(fname, "/sys/class/ubi/ubi%u_%u/name", ubi_devnum, i);
+		if (open_read_close(fname, buf, sizeof(buf)) <= 0)
+			continue;
+
+		strchrnul(buf, '\n')[0] = '\0';
+		if (strcmp(vol_name, buf) == 0)
+			return i;
+	}
+	bb_error_msg_and_die("volume '%s' not found", vol_name);
+}
diff --git a/miscutils/ubi_tools.c b/miscutils/ubi_tools.c
index dd1bda3..ac0c56d 100644
--- a/miscutils/ubi_tools.c
+++ b/miscutils/ubi_tools.c
@@ -195,7 +195,7 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
 	} else
 
 //usage:#define ubimkvol_trivial_usage
-//usage:       "UBI_DEVICE -N NAME [-s SIZE | -m]"
+//usage:       "-N NAME [-s SIZE | -m] UBI_DEVICE"
 //usage:#define ubimkvol_full_usage "\n\n"
 //usage:       "Create UBI volume\n"
 //usage:     "\n	-a ALIGNMENT	Volume alignment (default 1)"
@@ -212,9 +212,7 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
 			unsigned num;
 			char *p;
 
-			if (sscanf(ubi_ctrl, "/dev/ubi%u", &num) != 1)
-				bb_error_msg_and_die("wrong format of UBI device name");
-
+			num = ubi_devnum_from_devname(ubi_ctrl);
 			p = path_sys_class_ubi_ubi + sprintf(path_sys_class_ubi_ubi, "%u/", num);
 
 			strcpy(p, "avail_eraseblocks");
@@ -248,20 +246,31 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
 	} else
 
 //usage:#define ubirmvol_trivial_usage
-//usage:       "UBI_DEVICE -n VOLID"
+//usage:       "-n VOLID / -N VOLNAME UBI_DEVICE"
 //usage:#define ubirmvol_full_usage "\n\n"
 //usage:       "Remove UBI volume\n"
 //usage:     "\n	-n VOLID	Volume ID"
+//usage:     "\n	-N VOLNAME	Volume name"
 	if (do_rmvol) {
-		if (!(opts & OPTION_n))
+		if (!(opts & (OPTION_n|OPTION_N)))
 			bb_error_msg_and_die("volume id not specified");
 
-		/* FIXME? kernel expects int32_t* here: */
-		xioctl(fd, UBI_IOCRMVOL, &vol_id);
+		if (opts & OPTION_N) {
+			unsigned num = ubi_devnum_from_devname(ubi_ctrl);
+			vol_id = get_volid_by_name(num, vol_name);
+		}
+
+		if (sizeof(vol_id) != 4) {
+			/* kernel expects int32_t* in this ioctl */
+			int32_t t = vol_id;
+			xioctl(fd, UBI_IOCRMVOL, &t);
+		} else {
+			xioctl(fd, UBI_IOCRMVOL, &vol_id);
+		}
 	} else
 
 //usage:#define ubirsvol_trivial_usage
-//usage:       "UBI_DEVICE -n VOLID -s SIZE"
+//usage:       "-n VOLID -s SIZE UBI_DEVICE"
 //usage:#define ubirsvol_full_usage "\n\n"
 //usage:       "Resize UBI volume\n"
 //usage:     "\n	-n VOLID	Volume ID"
@@ -279,7 +288,7 @@ int ubi_tools_main(int argc UNUSED_PARAM, char **argv)
 	} else
 
 //usage:#define ubiupdatevol_trivial_usage
-//usage:       "UBI_DEVICE [-t | [-s SIZE] IMG_FILE]"
+//usage:       "[-t | [-s SIZE] IMG_FILE] UBI_DEVICE"
 //usage:#define ubiupdatevol_full_usage "\n\n"
 //usage:       "Update UBI volume\n"
 //usage:     "\n	-t	Truncate to zero size"
diff --git a/miscutils/ubirename.c b/miscutils/ubirename.c
index 455a494..d6ccfcb 100644
--- a/miscutils/ubirename.c
+++ b/miscutils/ubirename.c
@@ -30,12 +30,10 @@
 #endif
 
 // from ubi-media.h
-#define UBI_VOL_NAME_MAX 127
+#define UBI_MAX_VOLUME_NAME 127
 #define UBI_MAX_VOLUMES  128
 // end ubi-media.h
 
-#define UBI_MAX_VOLUME_NAME  UBI_VOL_NAME_MAX
-
 // from ubi-user.h
 /* ioctl commands of UBI character devices */
 #define UBI_IOC_MAGIC 'o'
@@ -64,7 +62,7 @@ int ubirename_main(int argc, char **argv)
 	struct ubi_rnvol_req *rnvol;
 	const char *ubi_devname;
 	unsigned ubi_devnum;
-	unsigned i, n;
+	unsigned n;
 
 	/* argc can be 4, 6, 8, ... */
 	if ((argc & 1) || (argc >>= 1) < 2)
@@ -76,27 +74,12 @@ int ubirename_main(int argc, char **argv)
 		bb_error_msg_and_die("too many renames requested");
 
 	ubi_devname = argv[1];
-	if (sscanf(ubi_devname, "/dev/ubi%u", &ubi_devnum) != 1)
-		bb_error_msg_and_die("not a ubi device: '%s'", ubi_devname);
+	ubi_devnum = ubi_devnum_from_devname(ubi_devname);
 
 	n = 0;
 	argv += 2;
 	while (argv[0]) {
-		for (i = 0; i < UBI_MAX_VOLUMES; i++) {
-			char buf[UBI_VOL_NAME_MAX + 1];
-			char fname[sizeof("/sys/class/ubi/ubi%u_%u/name") + 2 * sizeof(int)*3];
-
-			sprintf(fname, "/sys/class/ubi/ubi%u_%u/name", ubi_devnum, i);
-			if (open_read_close(fname, buf, sizeof(buf)) <= 0)
-				continue;
-
-			strchrnul(buf, '\n')[0] = '\0';
-			if (strcmp(buf, argv[0]) == 0)
-				goto found;
-		}
-		bb_error_msg_and_die("no volume '%s' found", argv[0]);
- found:
-		rnvol->ents[n].vol_id = i;
+		rnvol->ents[n].vol_id = get_volid_by_name(ubi_devnum, argv[0]);
 		rnvol->ents[n].name_len = strlen(argv[1]);
 		if (rnvol->ents[n].name_len >= sizeof(rnvol->ents[n].name))
 			bb_error_msg_and_die("new name '%s' is too long", argv[1]);