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 64e61cd26..35c28df51 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 000000000..7d3b2952d
--- /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 dd1bda300..ac0c56d6b 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 455a49485..d6ccfcb10 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]);