[systemd-devel] =?y?q?=5BPATCH=5D=20systemctl=3A=20add=20command=20list-dependencies?=
Lukas Nykryn
lnykryn at redhat.com
Thu Jan 17 10:28:07 PST 2013
systemctl list-dependencies lists all unit's dependecies and
recursively expands all subsidiary target units into a tree.
Primary purpose for this command is to show all units which are
enabled in specified target.
---
man/systemctl.xml | 11 +++
src/shared/util.c | 2 +
src/shared/util.h | 1 +
src/systemctl/systemctl.c | 227 +++++++++++++++++++++++++++++++++++++++++++++-
4 files changed, 239 insertions(+), 2 deletions(-)
diff --git a/man/systemctl.xml b/man/systemctl.xml
index 48c5a1c..f223383 100644
--- a/man/systemctl.xml
+++ b/man/systemctl.xml
@@ -997,6 +997,17 @@
dependencies.</para></listitem>
</varlistentry>
<varlistentry>
+ <term><command>list-dependencies [NAME]</command></term>
+
+ <listitem><para>
+ Shows required and wanted units of given unit.
+ Target units are recursively expanded.
+ When <option>--all</option> is passed
+ dependency tree is generated for all
+ subsidiary units.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
<term><command>snapshot [NAME]</command></term>
<listitem><para>Create a snapshot. If
diff --git a/src/shared/util.c b/src/shared/util.c
index 0161f3e..102f45c 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -5649,12 +5649,14 @@ const char *draw_special_char(DrawSpecialChar ch) {
[DRAW_TREE_VERT] = "\342\224\202 ", /* │ */
[DRAW_TREE_BRANCH] = "\342\224\234\342\224\200", /* ├─ */
[DRAW_TREE_RIGHT] = "\342\224\224\342\224\200", /* └─ */
+ [DRAW_TREE_SPACE] = " ", /* */
[DRAW_TRIANGULAR_BULLET] = "\342\200\243 ", /* ‣ */
},
/* ASCII fallback */ {
[DRAW_TREE_VERT] = "| ",
[DRAW_TREE_BRANCH] = "|-",
[DRAW_TREE_RIGHT] = "`-",
+ [DRAW_TREE_SPACE] = " ",
[DRAW_TRIANGULAR_BULLET] = "> ",
}
};
diff --git a/src/shared/util.h b/src/shared/util.h
index bbf744e..cdaff45 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -555,6 +555,7 @@ typedef enum DrawSpecialChar {
DRAW_TREE_VERT,
DRAW_TREE_BRANCH,
DRAW_TREE_RIGHT,
+ DRAW_TREE_SPACE,
DRAW_TRIANGULAR_BULLET,
_DRAW_SPECIAL_CHAR_MAX
} DrawSpecialChar;
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index a2ad0de..442179d 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -710,6 +710,226 @@ static int list_unit_files(DBusConnection *bus, char **args) {
return 0;
}
+static int list_dependencies_print(const char *name, int level, unsigned int branches, bool last) {
+ int i;
+ _cleanup_free_ char *n = NULL;
+ size_t len = 0;
+ size_t max_len = MAX(columns(),20);
+
+ for (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", draw_special_char(branches & (1 << i) ? DRAW_TREE_VERT : DRAW_TREE_SPACE));
+ }
+ len += 2;
+ if(len > max_len - 3 && !arg_full) {
+ printf("%s...\n",max_len % 2 ? "" : " ");
+ return 0;
+ }
+ printf("%s", draw_special_char(last ? DRAW_TREE_RIGHT : DRAW_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_get_dependencies(DBusConnection *bus, const char *name, char ***deps) {
+ static const char * const dependencies[] = {
+ "Requires",
+ "RequiresOverridable",
+ "Requisite",
+ "RequisiteOverridable",
+ "Wants"
+ };
+
+ _cleanup_free_ char *path;
+ const char *interface = "org.freedesktop.systemd1.Unit";
+
+ _cleanup_dbus_message_unref_ DBusMessage *reply = NULL;
+ DBusMessageIter iter, sub, sub2, sub3;
+
+ int r = 0;
+ unsigned int i;
+
+ char **ret = NULL;
+ char **c;
+
+ assert(bus);
+ assert(name);
+ assert(deps);
+
+ path = unit_dbus_path_from_name(name);
+ if (path == NULL) {
+ r = -EINVAL;
+ goto finish;
+ }
+
+ r = bus_method_call_with_reply(
+ bus,
+ "org.freedesktop.systemd1",
+ path,
+ "org.freedesktop.DBus.Properties",
+ "GetAll",
+ &reply,
+ NULL,
+ DBUS_TYPE_STRING, &interface,
+ DBUS_TYPE_INVALID);
+ if (r < 0)
+ goto finish;
+
+ if (!dbus_message_iter_init(reply, &iter) ||
+ dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY ||
+ dbus_message_iter_get_element_type(&iter) != DBUS_TYPE_DICT_ENTRY) {
+ log_error("Failed to parse reply.");
+ r = -EIO;
+ goto finish;
+ }
+
+ dbus_message_iter_recurse(&iter, &sub);
+
+ while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
+ const char *prop;
+
+ if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_DICT_ENTRY) {
+ log_error("Failed to parse reply.");
+ r = -EIO;
+ goto finish;
+ }
+
+ dbus_message_iter_recurse(&sub, &sub2);
+
+ if (bus_iter_get_basic_and_next(&sub2, DBUS_TYPE_STRING, &prop, true) < 0) {
+ log_error("Failed to parse reply.");
+ r = -EIO;
+ goto finish;
+ }
+
+ if (dbus_message_iter_get_arg_type(&sub2) != DBUS_TYPE_VARIANT) {
+ log_error("Failed to parse reply.");
+ r = -EIO;
+ goto finish;
+ }
+
+ dbus_message_iter_recurse(&sub2, &sub3);
+
+ dbus_message_iter_next(&sub);
+
+ for (i = 0; i < ELEMENTSOF(dependencies); i++)
+ if (streq(dependencies[i], prop)) {
+ break;
+ }
+
+ if (i == ELEMENTSOF(dependencies))
+ continue;
+
+ if (dbus_message_iter_get_arg_type(&sub3) == DBUS_TYPE_ARRAY) {
+ if (dbus_message_iter_get_element_type(&sub3) == DBUS_TYPE_STRING) {
+ DBusMessageIter sub4;
+ dbus_message_iter_recurse(&sub3, &sub4);
+
+ while (dbus_message_iter_get_arg_type(&sub4) != DBUS_TYPE_INVALID) {
+ const char *s;
+
+ assert(dbus_message_iter_get_arg_type(&sub4) == DBUS_TYPE_STRING);
+ dbus_message_iter_get_basic(&sub4, &s);
+ c = strv_append(ret, s);
+ if (c == NULL) {
+ r = log_oom();
+ goto finish;
+ }
+ strv_free(ret);
+ ret = c;
+ dbus_message_iter_next(&sub4);
+ }
+ }
+ }
+ }
+finish:
+ if (r < 0)
+ strv_freep(&ret);
+ *deps = ret;
+ return r;
+}
+
+static int list_dependencies_compare(const void *_a, const void *_b) {
+ const char **a = (const char**) _a, **b = (const char**) _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(DBusConnection *bus, const char *name, int level, char **units, unsigned int branches) {
+ char **deps = NULL;
+ char **c;
+ char **u = NULL;
+ int r = 0;
+
+ u = strv_append(units, name);
+ if(!u)
+ return log_oom();
+
+ r = list_dependencies_get_dependencies(bus, name, &deps);
+ if (r < 0)
+ goto finish;
+
+ qsort(deps, strv_length(deps), sizeof (char*), list_dependencies_compare);
+
+ STRV_FOREACH(c, deps) {
+ if (strv_contains(u, *c)) {
+ r = list_dependencies_print("...", level + 1, (branches << 1) | (c[1] == NULL ? 0 : 1), 1);
+ if(r < 0)
+ goto finish;
+ continue;
+ }
+
+ r = list_dependencies_print(*c, level, branches, c[1] == NULL);
+ if(r < 0)
+ goto finish;
+
+ if (arg_all || unit_name_to_type(*c) == UNIT_TARGET) {
+ r = list_dependencies_one(bus, *c, level + 1, u, (branches << 1) | (c[1] == NULL ? 0 : 1));
+ if(r < 0)
+ goto finish;
+ }
+ }
+ r = 0;
+finish:
+ strv_free(deps);
+ strv_free(u);
+
+ return r;
+}
+
+static int list_dependencies(DBusConnection *bus, char **args) {
+ int r = 0;
+ _cleanup_free_ char *unit = NULL;
+
+ assert(bus);
+ assert(args[1]);
+
+ unit = unit_name_mangle(args[1]);
+ if (!unit)
+ return log_oom();
+
+ pager_open_if_enabled();
+ printf("%s\n", unit);
+ r = list_dependencies_one(bus, unit, 0, NULL, 0);
+ return r;
+}
+
static int dot_one_property(const char *name, const char *prop, DBusMessageIter *iter) {
static const char * const colors[] = {
@@ -4063,7 +4283,7 @@ static int systemctl_help(void) {
" status [NAME...|PID...] Show runtime status of one or more units\n"
" show [NAME...|JOB...] Show properties of one or more\n"
" units/jobs or the manager\n"
- " help [NAME...|PID...] Show manual for one or more units\n"
+ " help [NAME...|PID...] Show manual for one or more units\n"
" reset-failed [NAME...] Reset failed state for all, one, or more\n"
" units\n"
" set-cgroup [NAME] [CGROUP...] Add unit to a control group\n"
@@ -4072,7 +4292,9 @@ static int systemctl_help(void) {
" Set control group attribute\n"
" unset-cgroup-attr [NAME] [ATTR...]\n"
" Unset control group attribute\n"
- " load [NAME...] Load one or more units\n\n"
+ " load [NAME...] Load one or more units\n"
+ " list-dependencies [NAME] Recursively show units which are required\n"
+ " or wanted by this unit\n\n"
"Unit File Commands:\n"
" list-unit-files List installed unit files\n"
" enable [NAME...] Enable one or more unit files\n"
@@ -5088,6 +5310,7 @@ static int systemctl_main(DBusConnection *bus, int argc, char *argv[], DBusError
{ "unmask", MORE, 2, enable_unit },
{ "link", MORE, 2, enable_unit },
{ "switch-root", MORE, 2, switch_root },
+ { "list-dependencies", EQUAL, 2, list_dependencies },
};
int left;
--
1.7.11.7
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