findmnt: use zero to separate lines in multi-line cells

Fixes: https://github.com/util-linux/util-linux/issues/2533
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/findmnt.8.adoc b/misc-utils/findmnt.8.adoc
index 0cb7f0e6c0fa7e9533220bf4829b6a33fa2efefa..72a1ecf2a2f74eb05b19873c4daac6d4d344627f 100644 (file)
--- a/misc-utils/findmnt.8.adoc
+++ b/misc-utils/findmnt.8.adoc
@@ -105,6 +105,8 @@ Output almost all available columns. The columns that require *--poll* are not i
 
 *-P*, *--pairs*::
 Produce output in the form of key="value" pairs. All potentially unsafe value characters are hex-escaped (\x<code>). See also option *--shell*.
++
+Note that SOURCES column, use multi-line cells. In these cases, the column use an array-like formatting in the output, for example *name=("aaa" "bbb" "ccc")*.
 
 *-p*, *--poll*[_=list_]::
 Monitor changes in the _/proc/self/mountinfo_ file. Supported actions are: mount, umount, remount and move. More than one action may be specified in a comma-separated list. All actions are monitored by default.
@@ -131,6 +133,8 @@ Print recursively all submounts for the selected filesystems. The restrictions d
 
 *-r*, *--raw*::
 Use raw output format. All potentially unsafe characters are hex-escaped (\x<code>).
++
+Note that column SOURCES, use multi-line cells. In these cases, the column may produce more strings on the same line.
 
 *--real*::
 Print only real filesystems.

diff --git a/misc-utils/findmnt.c b/misc-utils/findmnt.c
index cb091201b5278f3810c75fb29d9dc8dab44e9cc0..6865d96af170ac5d8d266c95051c398d33b1738b 100644 (file)
--- a/misc-utils/findmnt.c
+++ b/misc-utils/findmnt.c
@@ -511,7 +511,7 @@ static char *get_vfs_attr(struct libmnt_fs *fs, int sizetype)
 
 /* reads sources from libmount/libblkid
  */
-static char *get_data_col_sources(struct libmnt_fs *fs, int evaluate)
+static char *get_data_col_sources(struct libmnt_fs *fs, int evaluate, size_t *datasiz)
 {
        const char *tag = NULL, *p = NULL;
        int i = 0;
@@ -565,14 +565,14 @@ static char *get_data_col_sources(struct libmnt_fs *fs, int evaluate)
                if (!dev)
                        continue;
                if (i != 0)
-                       ul_buffer_append_data(&buf, "\n", 1);
+                       ul_buffer_append_data(&buf, "\0", 1);
                ul_buffer_append_string(&buf, blkid_dev_devname(dev));
                i++;
        }
        blkid_dev_iterate_end(iter);
        free(val);
 
-       return ul_buffer_get_data(&buf, NULL, NULL);
+       return ul_buffer_get_data(&buf, datasiz, NULL);
 
 nothing:
        free(val);
@@ -581,7 +581,7 @@ nothing:
 
 /* reads FS data from libmount
  */
-static char *get_data(struct libmnt_fs *fs, int num)
+static char *get_data(struct libmnt_fs *fs, int num, size_t *datasiz)
 {
        char *str = NULL;
        int col_id = get_column_id(num);
@@ -589,7 +589,7 @@ static char *get_data(struct libmnt_fs *fs, int num)
        switch (col_id) {
        case COL_SOURCES:
                /* print all devices with the same tag (LABEL, UUID) */
-               str = get_data_col_sources(fs, flags & FL_EVALUATE);
+               str = get_data_col_sources(fs, flags & FL_EVALUATE, datasiz);
                if (str)
                        break;
 
@@ -730,7 +730,8 @@ static char *get_data(struct libmnt_fs *fs, int num)
 static char *get_tabdiff_data(struct libmnt_fs *old_fs,
                                    struct libmnt_fs *new_fs,
                                    int change,
-                                   int num)
+                                   int num,
+                                   size_t *datasiz)
 {
        char *str = NULL;
 
@@ -769,14 +770,30 @@ static char *get_tabdiff_data(struct libmnt_fs *old_fs,
                break;
        default:
                if (new_fs)
-                       str = get_data(new_fs, num);
+                       str = get_data(new_fs, num, datasiz);
                else
-                       str = get_data(old_fs, num);
+                       str = get_data(old_fs, num, datasiz);
                break;
        }
        return str;
 }
 
+static void set_line_data(struct libscols_line *ln, size_t i, char *data, size_t datasiz)
+{
+       int rc;
+       struct libscols_cell *ce;
+
+       ce = scols_line_get_cell(ln, i);
+       if (!ce)
+               return;
+       if (datasiz)
+               rc = scols_cell_refer_memory(ce, data, datasiz);
+       else
+               rc = scols_cell_refer_data(ce, data);
+       if (rc)
+               err(EXIT_FAILURE, _("failed to add output data"));
+}
+
 /* adds one line to the output @tab */
 static struct libscols_line *add_line(struct libscols_table *table, struct libmnt_fs *fs,
                                        struct libscols_line *parent)
@@ -788,8 +805,11 @@ static struct libscols_line *add_line(struct libscols_table *table, struct libmn
                err(EXIT_FAILURE, _("failed to allocate output line"));
 
        for (i = 0; i < ncolumns; i++) {
-               if (scols_line_refer_data(line, i, get_data(fs, i)))
-                       err(EXIT_FAILURE, _("failed to add output data"));
+               size_t datasiz = 0;
+               char *data = get_data(fs, i, &datasiz);
+
+               if (data)
+                       set_line_data(line, i, data, datasiz);
        }
 
        scols_line_set_userdata(line, fs);
@@ -806,9 +826,11 @@ static struct libscols_line *add_tabdiff_line(struct libscols_table *table, stru
                err(EXIT_FAILURE, _("failed to allocate output line"));
 
        for (i = 0; i < ncolumns; i++) {
-               if (scols_line_refer_data(line, i,
-                               get_tabdiff_data(old_fs, new_fs, change, i)))
-                       err(EXIT_FAILURE, _("failed to add output data"));
+               size_t datasiz = 0;
+               char *data = get_tabdiff_data(old_fs, new_fs, change, i, &datasiz);
+
+               if (data)
+                       set_line_data(line, i, data, datasiz);
        }
 
        return line;
@@ -1793,13 +1815,11 @@ int main(int argc, char *argv[])
                        goto leave;
                }
                /* multi-line cells (now used for SOURCES) */
-               if (fl & SCOLS_FL_WRAP) {
+               if (fl & SCOLS_FL_WRAP)
                        scols_column_set_wrapfunc(cl,
-                                               scols_wrapnl_chunksize,
-                                               scols_wrapnl_nextchunk,
+                                               NULL,
+                                               scols_wrapzero_nextchunk,
                                                NULL);
-                       scols_column_set_safechars(cl, "\n");
-               }
                if (flags & FL_JSON) {
                        switch (id) {
                        case COL_SIZE: