Add column layout skeleton and git-column
A column option string consists of many token separated by either
a space or a comma. A token belongs to one of three groups:
- enabling: always, never and auto
- layout mode: currently plain (which does not layout at all)
- other future tuning flags
git-column can be used to pipe output to from a command that wants
column layout, but not to mess with its own output code. Simpler output
code can be changed to use column layout code directly.
Thanks-to: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/column.c b/column.c
new file mode 100644
index 0000000..3349f58
--- /dev/null
+++ b/column.c
@@ -0,0 +1,169 @@
+#include "cache.h"
+#include "column.h"
+#include "string-list.h"
+#include "parse-options.h"
+
+/* Display without layout when not enabled */
+static void display_plain(const struct string_list *list,
+ const char *indent, const char *nl)
+{
+ int i;
+
+ for (i = 0; i < list->nr; i++)
+ printf("%s%s%s", indent, list->items[i].string, nl);
+}
+
+void print_columns(const struct string_list *list, unsigned int colopts,
+ const struct column_options *opts)
+{
+ struct column_options nopts;
+
+ if (!list->nr)
+ return;
+ assert((colopts & COL_ENABLE_MASK) != COL_AUTO);
+
+ memset(&nopts, 0, sizeof(nopts));
+ nopts.indent = opts && opts->indent ? opts->indent : "";
+ nopts.nl = opts && opts->nl ? opts->nl : "\n";
+ nopts.padding = opts ? opts->padding : 1;
+ nopts.width = opts && opts->width ? opts->width : term_columns() - 1;
+ if (!column_active(colopts)) {
+ display_plain(list, "", "\n");
+ return;
+ }
+ switch (COL_LAYOUT(colopts)) {
+ case COL_PLAIN:
+ display_plain(list, nopts.indent, nopts.nl);
+ break;
+ default:
+ die("BUG: invalid layout mode %d", COL_LAYOUT(colopts));
+ }
+}
+
+int finalize_colopts(unsigned int *colopts, int stdout_is_tty)
+{
+ if ((*colopts & COL_ENABLE_MASK) == COL_AUTO) {
+ if (stdout_is_tty < 0)
+ stdout_is_tty = isatty(1);
+ *colopts &= ~COL_ENABLE_MASK;
+ if (stdout_is_tty)
+ *colopts |= COL_ENABLED;
+ }
+ return 0;
+}
+
+struct colopt {
+ const char *name;
+ unsigned int value;
+ unsigned int mask;
+};
+
+#define LAYOUT_SET 1
+#define ENABLE_SET 2
+
+static int parse_option(const char *arg, int len, unsigned int *colopts,
+ int *group_set)
+{
+ struct colopt opts[] = {
+ { "always", COL_ENABLED, COL_ENABLE_MASK },
+ { "never", COL_DISABLED, COL_ENABLE_MASK },
+ { "auto", COL_AUTO, COL_ENABLE_MASK },
+ { "plain", COL_PLAIN, COL_LAYOUT_MASK },
+ };
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(opts); i++) {
+ int arg_len = len, name_len;
+ const char *arg_str = arg;
+
+ name_len = strlen(opts[i].name);
+ if (arg_len != name_len ||
+ strncmp(arg_str, opts[i].name, name_len))
+ continue;
+
+ switch (opts[i].mask) {
+ case COL_ENABLE_MASK:
+ *group_set |= ENABLE_SET;
+ break;
+ case COL_LAYOUT_MASK:
+ *group_set |= LAYOUT_SET;
+ break;
+ }
+
+ if (opts[i].mask)
+ *colopts = (*colopts & ~opts[i].mask) | opts[i].value;
+ return 0;
+ }
+
+ return error("unsupported option '%s'", arg);
+}
+
+static int parse_config(unsigned int *colopts, const char *value)
+{
+ const char *sep = " ,";
+ int group_set = 0;
+
+ while (*value) {
+ int len = strcspn(value, sep);
+ if (len) {
+ if (parse_option(value, len, colopts, &group_set))
+ return -1;
+
+ value += len;
+ }
+ value += strspn(value, sep);
+ }
+ /*
+ * Setting layout implies "always" if neither always, never
+ * nor auto is specified.
+ *
+ * Current value in COL_ENABLE_MASK is disregarded. This means if
+ * you set column.ui = auto and pass --column=row, then "auto"
+ * will become "always".
+ */
+ if ((group_set & LAYOUT_SET) && !(group_set & ENABLE_SET))
+ *colopts = (*colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
+ return 0;
+}
+
+static int column_config(const char *var, const char *value,
+ const char *key, unsigned int *colopts)
+{
+ if (!value)
+ return config_error_nonbool(var);
+ if (parse_config(colopts, value))
+ return error("invalid column.%s mode %s", key, value);
+ return 0;
+}
+
+int git_column_config(const char *var, const char *value,
+ const char *command, unsigned int *colopts)
+{
+ const char *it = skip_prefix(var, "column.");
+ if (!it)
+ return 0;
+
+ if (!strcmp(it, "ui"))
+ return column_config(var, value, "ui", colopts);
+
+ if (command && !strcmp(it, command))
+ return column_config(var, value, it, colopts);
+
+ return 0;
+}
+
+int parseopt_column_callback(const struct option *opt,
+ const char *arg, int unset)
+{
+ unsigned int *colopts = opt->value;
+ *colopts |= COL_PARSEOPT;
+ *colopts &= ~COL_ENABLE_MASK;
+ if (unset) /* --no-column == never */
+ return 0;
+ /* --column == always unless "arg" states otherwise */
+ *colopts |= COL_ENABLED;
+ if (arg)
+ return parse_config(colopts, arg);
+
+ return 0;
+}
