1 files changed, 175 insertions, 0 deletions
diff --git a/src/systemctl/systemctl-list-dependencies.c b/src/systemctl/systemctl-list-dependencies.c
new file mode 100644
index 0000000..25ce09c
--- /dev/null
+++ b/src/systemctl/systemctl-list-dependencies.c
@@ -0,0 +1,175 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "locale-util.h"
+#include "sort-util.h"
+#include "special.h"
+#include "systemctl-list-dependencies.h"
+#include "systemctl-util.h"
+#include "systemctl.h"
+#include "terminal-util.h"
+
+static int list_dependencies_print(const char *name, int level, unsigned branches, bool last) {
+        _cleanup_free_ char *n = NULL;
+        size_t max_len = MAX(columns(),20u);
+        size_t len = 0;
+
+        if (!arg_plain) {
+
+                for (int i = level - 1; i >= 0; i--) {
+                        len += 2;
+                        if (len > max_len - 3 && !arg_full) {
+                                printf("%s...\n",max_len % 2 ? "" : " ");
+                                return 0;
+                        }
+                        printf("%s", special_glyph(branches & (1 << i) ? SPECIAL_GLYPH_TREE_VERTICAL : SPECIAL_GLYPH_TREE_SPACE));
+                }
+                len += 2;
+
+                if (len > max_len - 3 && !arg_full) {
+                        printf("%s...\n",max_len % 2 ? "" : " ");
+                        return 0;
+                }
+
+                printf("%s", special_glyph(last ? SPECIAL_GLYPH_TREE_RIGHT : SPECIAL_GLYPH_TREE_BRANCH));
+        }
+
+        if (arg_full) {
+                printf("%s\n", name);
+                return 0;
+        }
+
+        n = ellipsize(name, max_len-len, 100);
+        if (!n)
+                return log_oom();
+
+        printf("%s\n", n);
+        return 0;
+}
+
+static int list_dependencies_compare(char * const *a, char * const *b) {
+        if (unit_name_to_type(*a) == UNIT_TARGET && unit_name_to_type(*b) != UNIT_TARGET)
+                return 1;
+        if (unit_name_to_type(*a) != UNIT_TARGET && unit_name_to_type(*b) == UNIT_TARGET)
+                return -1;
+
+        return strcasecmp(*a, *b);
+}
+
+static int list_dependencies_one(
+                sd_bus *bus,
+                const char *name,
+                int level,
+                char ***units,
+                unsigned branches) {
+
+        _cleanup_strv_free_ char **deps = NULL;
+        int r;
+        bool circular = false;
+
+        assert(bus);
+        assert(name);
+        assert(units);
+
+        r = strv_extend(units, name);
+        if (r < 0)
+                return log_oom();
+
+        r = unit_get_dependencies(bus, name, &deps);
+        if (r < 0)
+                return r;
+
+        typesafe_qsort(deps, strv_length(deps), list_dependencies_compare);
+
+        STRV_FOREACH(c, deps) {
+                if (strv_contains(*units, *c)) {
+                        circular = true;
+                        continue;
+                }
+
+                if (arg_plain)
+                        printf("  ");
+                else {
+                        UnitActiveState active_state = _UNIT_ACTIVE_STATE_INVALID;
+                        const char *on;
+
+                        (void) get_state_one_unit(bus, *c, &active_state);
+
+                        switch (active_state) {
+                        case UNIT_ACTIVE:
+                        case UNIT_RELOADING:
+                        case UNIT_ACTIVATING:
+                                on = ansi_highlight_green();
+                                break;
+
+                        case UNIT_INACTIVE:
+                        case UNIT_DEACTIVATING:
+                                on = ansi_normal();
+                                break;
+
+                        default:
+                                on = ansi_highlight_red();
+                                break;
+                        }
+
+                        printf("%s%s%s ", on, special_glyph(unit_active_state_to_glyph(active_state)), ansi_normal());
+                }
+
+                r = list_dependencies_print(*c, level, branches, /* last = */ c[1] == NULL && !circular);
+                if (r < 0)
+                        return r;
+
+                if (arg_all || unit_name_to_type(*c) == UNIT_TARGET) {
+                       r = list_dependencies_one(bus, *c, level + 1, units, (branches << 1) | (c[1] == NULL ? 0 : 1));
+                       if (r < 0)
+                               return r;
+                }
+        }
+
+        if (circular && !arg_plain) {
+                printf("  ");
+                r = list_dependencies_print("...", level, branches, /* last = */ true);
+                if (r < 0)
+                        return r;
+        }
+
+        if (!arg_plain)
+                strv_remove(*units, name);
+
+        return 0;
+}
+
+int verb_list_dependencies(int argc, char *argv[], void *userdata) {
+        _cleanup_strv_free_ char **units = NULL, **done = NULL;
+        char **patterns;
+        sd_bus *bus;
+        int r;
+
+        r = acquire_bus(BUS_MANAGER, &bus);
+        if (r < 0)
+                return r;
+
+        patterns = strv_skip(argv, 1);
+        if (strv_isempty(patterns)) {
+                units = strv_new(SPECIAL_DEFAULT_TARGET);
+                if (!units)
+                        return log_oom();
+        } else {
+                r = expand_unit_names(bus, patterns, NULL, &units, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to expand names: %m");
+        }
+
+        pager_open(arg_pager_flags);
+
+        STRV_FOREACH(u, units) {
+                if (u != units)
+                        puts("");
+
+                puts(*u);
+                r = list_dependencies_one(bus, *u, 0, &done, 0);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}