cmd: ubi: Add 'ubi list' command for printing list of all UBI volumes

To allow easily iterate over all UBI volumes, add a new command which
either print all user UBI volumes on output or set them into env variable.

As UBI volumes can have arbitrary name/label, in most cases it is useful to
iterate them by their numbers. This can be achieved by -numeric flag.

This functionality is similar to already existing 'part list' command which
prints partitions on formatted block device.

Signed-off-by: Pali Rohár <pali@kernel.org>

diff --git a/cmd/ubi.c b/cmd/ubi.c
index fccbfdf..b61ae1e 100644 (file)
--- a/cmd/ubi.c
+++ b/cmd/ubi.c
@@ -27,6 +27,7 @@
 #include <ubi_uboot.h>
 #include <linux/errno.h>
 #include <jffs2/load_kernel.h>
+#include <linux/log2.h>
 
 #undef ubi_msg
 #define ubi_msg(fmt, ...) printf("UBI: " fmt "\n", ##__VA_ARGS__)
@@ -84,6 +85,70 @@ static int ubi_info(int layout)
        return 0;
 }
 
+static int ubi_list(const char *var, int numeric)
+{
+       size_t namelen, len, size;
+       char *str, *str2;
+       int i;
+
+       if (!var) {
+               for (i = 0; i < (ubi->vtbl_slots + 1); i++) {
+                       if (!ubi->volumes[i])
+                               continue;
+                       if (ubi->volumes[i]->vol_id >= UBI_INTERNAL_VOL_START)
+                               continue;
+                       printf("%d: %s\n",
+                              ubi->volumes[i]->vol_id,
+                              ubi->volumes[i]->name);
+               }
+               return 0;
+       }
+
+       len = 0;
+       size = 16;
+       str = malloc(size);
+       if (!str)
+               return 1;
+
+       for (i = 0; i < (ubi->vtbl_slots + 1); i++) {
+               if (!ubi->volumes[i])
+                       continue;
+               if (ubi->volumes[i]->vol_id >= UBI_INTERNAL_VOL_START)
+                       continue;
+
+               if (numeric)
+                       namelen = 10; /* strlen(stringify(INT_MAX)) */
+               else
+                       namelen = strlen(ubi->volumes[i]->name);
+
+               if (len + namelen + 1 > size) {
+                       size = roundup_pow_of_two(len + namelen + 1) * 2;
+                       str2 = realloc(str, size);
+                       if (!str2) {
+                               free(str);
+                               return 1;
+                       }
+                       str = str2;
+               }
+
+               if (len)
+                       str[len++] = ' ';
+
+               if (numeric) {
+                       len += sprintf(str + len, "%d", ubi->volumes[i]->vol_id) + 1;
+               } else {
+                       memcpy(str + len, ubi->volumes[i]->name, namelen);
+                       len += namelen;
+                       str[len] = 0;
+               }
+       }
+
+       env_set(var, str);
+       free(str);
+
+       return 0;
+}
+
 static int ubi_check_volumename(const struct ubi_volume *vol, char *name)
 {
        return strcmp(vol->name, name);
@@ -586,6 +651,21 @@ static int do_ubi(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
                return ubi_info(layout);
        }
 
+       if (strcmp(argv[1], "list") == 0) {
+               int numeric = 0;
+               if (argc >= 2 && argv[2][0] == '-') {
+                       if (strcmp(argv[2], "-numeric") == 0)
+                               numeric = 1;
+                       else
+                               return CMD_RET_USAGE;
+               }
+               if (!numeric && argc != 2 && argc != 3)
+                       return CMD_RET_USAGE;
+               if (numeric && argc != 3 && argc != 4)
+                       return CMD_RET_USAGE;
+               return ubi_list(argv[numeric ? 3 : 2], numeric);
+       }
+
        if (strcmp(argv[1], "check") == 0) {
                if (argc > 2)
                        return ubi_check(argv[2]);
@@ -725,6 +805,11 @@ U_BOOT_CMD(
                " header offset)\n"
        "ubi info [l[ayout]]"
                " - Display volume and ubi layout information\n"
+       "ubi list [flags]"
+               " - print the list of volumes\n"
+       "ubi list [flags] <varname>"
+               " - set environment variable to the list of volumes"
+               " (flags can be -numeric)\n"
        "ubi check volumename"
                " - check if volumename exists\n"
        "ubi create[vol] volume [size] [type] [id] [--skipcheck]\n"