column: add option '--table-header-as-columns' for using first line as table columns...

diff --git a/text-utils/column.1.adoc b/text-utils/column.1.adoc
index ac5e3ef1cd7b82585b4cde8711a140c8aa008b67..1abe5967ea2b8825ae563ce0ac0b8ba595eb7b54 100644 (file)
--- a/text-utils/column.1.adoc
+++ b/text-utils/column.1.adoc
@@ -182,6 +182,9 @@ This option is active by default for the last visible column.
 *-e, --table-header-repeat*::
 Print header line for each page.
 
+*-K, --table-header-as-columns*::
+Use the first input line as table header. This option is mutually exclusive with *--table-columns* and *--table-column*.
+
 *-W, --table-wrap* _columns_::
 Specify the columns where multi-line cells can be used for long text. By default, text is wrapped according to column width. Use *--wrap-separator* to wrap at custom separator characters instead.
 

diff --git a/text-utils/column.c b/text-utils/column.c
index 5a9e9a03b659bc4bafc5c6c4dba585570e6cc369..6b0c393028a9d2f46435cc8e2b422392dc75f80f 100644 (file)
--- a/text-utils/column.c
+++ b/text-utils/column.c
@@ -103,6 +103,7 @@ struct column_control {
        bool    greedy,
                json,
                header_repeat,
+               header_as_columns,      /* --table-header-as-columns */
                hide_unnamed,
                maxout : 1,
                keep_empty_lines,       /* --keep-empty-lines */
@@ -728,6 +729,32 @@ static void modify_table(struct column_control *ctl)
                reorder_table(ctl);
 }
 
+/* Parse first line as column names for --table-header-as-columns (-K). */
+static void parse_header_line(struct column_control *ctl, wchar_t *wcs0)
+{
+       wchar_t *sv = NULL, *wcs = wcs0;
+       char **names = NULL;
+
+       do {
+               wchar_t *wcdata = local_wcstok(ctl, wcs, &sv);
+               char *data;
+
+               if (!wcdata)
+                       break;
+
+               data = wcs_to_mbs(wcdata);
+               if (!data)
+                       err(EXIT_FAILURE, _("failed to allocate column name"));
+
+               if (ul_strv_extend(&names, data))
+                       err_oom();
+               free(data);
+               wcs = NULL;
+       } while (1);
+
+       ctl->tab_colnames = names;
+       ctl->header_as_columns = 0;
+}
 
 static int add_line_to_table(struct column_control *ctl, wchar_t *wcs0)
 {
@@ -735,6 +762,10 @@ static int add_line_to_table(struct column_control *ctl, wchar_t *wcs0)
        size_t n = 0;
        struct libscols_line *ln = NULL;
 
+       if (ctl->header_as_columns) {
+               parse_header_line(ctl, wcs0);
+               return 0;       /* first line was used as column names */
+       }
 
        if (!ctl->tab)
                init_table(ctl);
@@ -1004,6 +1035,7 @@ static void __attribute__((__noreturn__)) usage(void)
        fputs(_(" -d, --table-noheadings           don't print header\n"), out);
        fputs(_(" -m, --table-maxout               fill all available space\n"), out);
        fputs(_(" -e, --table-header-repeat        repeat header for each page\n"), out);
+       fputs(_(" -K, --table-header-as-columns    use the first row as table header\n"), out);
        fputs(_(" -H, --table-hide <columns>       don't print the columns\n"), out);
        fputs(_(" -R, --table-right <columns>      right align text in these columns\n"), out);
        fputs(_(" -T, --table-truncate <columns>   truncate text in the columns when necessary\n"), out);
@@ -1082,6 +1114,7 @@ int main(int argc, char **argv)
                { "table-wrap",          required_argument, NULL, 'W' },
                { "table-empty-lines",   no_argument,       NULL, 'L' }, /* deprecated */
                { "table-header-repeat", no_argument,       NULL, 'e' },
+               { "table-header-as-columns", no_argument,  NULL, 'K' },
                { "tree",                required_argument, NULL, 'r' },
                { "tree-id",             required_argument, NULL, 'i' },
                { "tree-parent",         required_argument, NULL, 'p' },
@@ -1091,7 +1124,7 @@ int main(int argc, char **argv)
                { NULL, 0, NULL, 0 },
        };
        static const ul_excl_t excl[] = {       /* rows and cols in ASCII order */
-               { 'C','N' },
+               { 'C','K','N' },
                { 'J','x' },
                { 't','x' },
                { 0 }
@@ -1106,7 +1139,7 @@ int main(int argc, char **argv)
        ctl.output_separator = "  ";
        ctl.input_separator = mbs_to_wcs("\t ");
 
-       while ((c = getopt_long(argc, argv, "C:c:dE:eH:hi:Jl:LN:n:mO:o:p:R:r:S:s:T:tVW:x", longopts, NULL)) != -1) {
+       while ((c = getopt_long(argc, argv, "C:c:dE:eH:hi:JKl:LN:n:mO:o:p:R:r:S:s:T:tVW:x", longopts, NULL)) != -1) {
 
                err_exclusive_options(c, longopts, excl, excl_st);
 
@@ -1141,6 +1174,10 @@ int main(int argc, char **argv)
                        ctl.json = 1;
                        ctl.mode = COLUMN_MODE_TABLE;
                        break;
+               case 'K':
+                       ctl.header_as_columns = 1;
+                       ctl.mode = COLUMN_MODE_TABLE;
+                       break;
                case 'L':
                        ctl.keep_empty_lines = 1;
                        break;
@@ -1235,7 +1272,7 @@ int main(int argc, char **argv)
                ctl.tab_colright || ctl.tab_colnames || ctl.tab_columns))
                errx(EXIT_FAILURE, _("option --table required for all --table-*"));
 
-       if (!ctl.tab_colnames && !ctl.tab_columns && ctl.json)
+       if (!ctl.tab_colnames && !ctl.tab_columns && !ctl.header_as_columns && ctl.json)
                errx(EXIT_FAILURE, _("option --table-columns or --table-column required for --json"));
 
        if (ctl.mode == COLUMN_MODE_TABLE)