libfdisk: make scripts portable between different sector sizes

Fixes: https://github.com/util-linux/util-linux/issues/1744
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libfdisk/src/script.c b/libfdisk/src/script.c
index d93b98171d4a38dc5cbfc60d6bb4672c386adf9a..b620edad5865401adb24fb277f5ea79e6a8db95a 100644 (file)
--- a/libfdisk/src/script.c
+++ b/libfdisk/src/script.c
@@ -63,6 +63,8 @@ struct fdisk_script {
        size_t                  nlines;
        struct fdisk_label      *label;
 
+       unsigned long           sector_size;            /* as defined by script */
+
        unsigned int            json : 1,               /* JSON output */
                                force_label : 1;        /* label: <name> specified */
 };
@@ -806,6 +808,19 @@ static int parse_line_header(struct fdisk_script *dp, char *s)
                        return -EINVAL;                 /* unknown label name */
                dp->force_label = 1;
 
+       } else if (strcmp(name, "sector-size") == 0) {
+               uint64_t x = 0;
+
+               if (ul_strtou64(value, &x, 10) != 0)
+                       return -EINVAL;
+               if (x > ULONG_MAX || x % 512)
+                       return -ERANGE;
+               dp->sector_size = (unsigned long) x;
+
+               if (dp->cxt && dp->sector_size && dp->cxt->sector_size
+                   && dp->sector_size != dp->cxt->sector_size)
+                       fdisk_warnx(dp->cxt, _("The script and device sector size differ; the sizes will be recalculated to match the device."));
+
        } else if (strcmp(name, "unit") == 0) {
                if (strcmp(value, "sectors") != 0)
                        return -EINVAL;                 /* only "sectors" supported */
@@ -966,6 +981,27 @@ static int skip_optional_sign(char **str)
        return 0;
 }
 
+static int recount_script2device_sectors(struct fdisk_script *dp, uint64_t *num)
+{
+       if (!dp->cxt ||
+           !dp->sector_size ||
+           !dp->cxt->sector_size)
+               return 0;
+
+       if (dp->sector_size > dp->cxt->sector_size)
+                *num *= (dp->sector_size / dp->cxt->sector_size);
+
+       else if (dp->sector_size < dp->cxt->sector_size) {
+               uint64_t x = dp->cxt->sector_size / dp->sector_size;
+
+               if (*num % x)
+                       return -EINVAL;
+               *num /= x;
+       }
+
+       return 0;
+}
+
 static int parse_start_value(struct fdisk_script *dp, struct fdisk_partition *pa, char **str)
 {
        char *tk;
@@ -997,7 +1033,14 @@ static int parse_start_value(struct fdisk_script *dp, struct fdisk_partition *pa
                                        goto done;
                                }
                                num /= dp->cxt->sector_size;
+                       } else {
+                               rc = recount_script2device_sectors(dp, &num);
+                               if (rc) {
+                                       fdisk_warnx(dp->cxt, _("Can't recalculate partition start to the device sectors"));
+                                       goto done;
+                               }
                        }
+
                        fdisk_partition_set_start(pa, num);
 
                        pa->movestart = sign == '-' ? FDISK_MOVE_DOWN :
@@ -1046,8 +1089,15 @@ static int parse_size_value(struct fdisk_script *dp, struct fdisk_partition *pa,
                                        goto done;
                                }
                                num /= dp->cxt->sector_size;
-                       } else   /* specified as number of sectors */
+                       } else {
+                               /* specified as number of sectors */
                                fdisk_partition_size_explicit(pa, 1);
+                               rc = recount_script2device_sectors(dp, &num);
+                               if (rc) {
+                                       fdisk_warnx(dp->cxt, _("Can't recalculate partition size to the device sectors"));
+                                       goto done;
+                               }
+                       }
 
                        fdisk_partition_set_size(pa, num);
                        pa->resize = sign == '-' ? FDISK_RESIZE_REDUCE :
@@ -1492,6 +1542,25 @@ int fdisk_apply_script_headers(struct fdisk_context *cxt, struct fdisk_script *d
        DBG(SCRIPT, ul_debugobj(dp, "applying script headers"));
        fdisk_set_script(cxt, dp);
 
+       if (dp->sector_size && dp->cxt->sector_size != dp->sector_size) {
+               /*
+                * Ignore last and first LBA if device sector size mismatch
+                * with sector size in script.  It would be possible to
+                * recalculate it, but for GPT it will not work in some cases
+                * as these offsets are calculated by relative number of
+                * sectors. It's better to use library defaults than try
+                * to be smart ...
+                */
+               if (fdisk_script_get_header(dp, "first-lba")) {
+                       fdisk_script_set_header(dp, "first-lba", NULL);
+                       fdisk_info(dp->cxt, _("Ingnore \"first-lba\" header due to sector size mismatch."));
+               }
+               if (fdisk_script_get_header(dp, "last-lba")) {
+                       fdisk_script_set_header(dp, "last-lba", NULL);
+                       fdisk_info(dp->cxt, _("Ingnore \"last-lba\" header due to sector size mismatch."));
+               }
+       }
+
        str = fdisk_script_get_header(dp, "grain");
        if (str) {
                uintmax_t sz;