[parted-devel] [PATCH v2] parted/ui: Count empty quoted strings as words in multi_word mode

[Sebastian Parschauer]

In non-interactive mode, the command line arguments are appended
to a string list with command_line_push_line() in multi_word mode.
That mode does not count empty strings as a word.
For mkpart and a GPT disk label, the partition name is picked up
from that string list. The partition name is mandatory and we
cannot make it optional. So it is not possible to set an empty
partition name from command line this way.
Also setting a default name is no option as this causes duplicate
/dev/disk/by-partlabel/ symlinks and systemd errors this way.

So count empty quoted strings as words in multi_word mode to allow
the following commands to set an empty partition name.

parted -s /dev/vdb mkpart "''" 1MiB 100%
parted -s /dev/vdb mkpart '""' ext3 1MiB 100%
parted -s /dev/vdb name 1 "''"

The quoting is required as in interactive mode the command
"mkpart " (with a trailing space) would set the partition name to
an empty string already.

Signed-off-by: Sebastian Parschauer <sparschauer at suse.de>
---
 parted/ui.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/parted/ui.c b/parted/ui.c
index 752860baa087..9991596a3a5a 100644
--- a/parted/ui.c
+++ b/parted/ui.c
@@ -719,6 +719,7 @@ void
 command_line_push_line (const char* line, int multi_word)
 {
         int     quoted = 0;
+        int     quotes_empty = 0;
         char    quote_char = 0;
         char    this_word [256];
         int     i;
@@ -746,6 +747,9 @@ command_line_push_line (const char* line, int multi_word)
 
                         if (quoted && *line == quote_char) {
                                 quoted = 0;
+                                /* allow empty partition name in script mode */
+                                if (!i)
+                                        quotes_empty = 1;
                                 continue;
                         }
 
@@ -753,9 +757,11 @@ command_line_push_line (const char* line, int multi_word)
                         if (quoted && line[0] == '\\' && line[1])
                                 line++;
 
+                        quotes_empty = 0;
                         this_word [i++] = *line;
                 }
-                if (i || !multi_word) {
+                if (i || !multi_word || quotes_empty) {
+                        quotes_empty = 0;
                         this_word [i] = 0;
                         command_line_push_word (this_word);
                 }
-- 
2.12.3