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mirror of https://github.com/systemd/systemd.git synced 2024-12-22 17:35:35 +03:00

systemctl: add "systemctl cat"

This commit is contained in:
Shawn Landden 2013-11-30 16:09:26 -08:00 committed by Zbigniew Jędrzejewski-Szmek
parent f74294c1da
commit e93c33d4aa
6 changed files with 187 additions and 2 deletions

1
TODO
View File

@ -356,7 +356,6 @@ Features:
- support "systemctl stop foobar@.service" to stop all units matching a certain template
- Something is wrong with symlink handling of "autovt@.service" in "systemctl list-unit-files"
- rework wait filter to not require match callback
- "systemctl cat" or "systemctl view" command or or so, that cats the backing unit file of a service, plus its drop-ins and shows them in a pager
- better error message if you run systemctl without systemd running
- systemctl status output should should include list of triggering units and their status
- in systemctl list-timers show time trggering units ran last

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@ -733,7 +733,16 @@ kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service
human-readable output.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><command>cat <replaceable>NAME</replaceable>...</command></term>
<listitem>
<para>Show backing files of one or more units.
Prints the fragment, drop-ins, and source (sysvinit compat)
of units. Each file is preceded by a comment which includes the
file name.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><command>set-property <replaceable>NAME</replaceable> <replaceable>ASSIGNMENT</replaceable>...</command></term>

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@ -20,6 +20,7 @@
***/
#include <unistd.h>
#include <sys/sendfile.h>
#include "fileio.h"
#include "util.h"
#include "strv.h"
@ -117,6 +118,77 @@ int read_one_line_file(const char *fn, char **line) {
return 0;
}
ssize_t sendfile_full(int out_fd, const char *fn) {
_cleanup_fclose_ FILE *f;
struct stat st;
int r;
ssize_t s;
size_t n, l;
_cleanup_free_ char *buf = NULL;
assert(out_fd > 0);
assert(fn);
f = fopen(fn, "r");
if (!f)
return -errno;
r = fstat(fileno(f), &st);
if (r < 0)
return -errno;
s = sendfile(out_fd, fileno(f), NULL, st.st_size);
if (s < 0)
if (errno == EINVAL || errno == ENOSYS) {
/* continue below */
} else
return -errno;
else
return s;
/* sendfile() failed, fall back to read/write */
/* Safety check */
if (st.st_size > 4*1024*1024)
return -E2BIG;
n = st.st_size > 0 ? st.st_size : LINE_MAX;
l = 0;
while (true) {
char *t;
size_t k;
t = realloc(buf, n);
if (!t)
return -ENOMEM;
buf = t;
k = fread(buf + l, 1, n - l, f);
if (k <= 0) {
if (ferror(f))
return -errno;
break;
}
l += k;
n *= 2;
/* Safety check */
if (n > 4*1024*1024)
return -E2BIG;
}
r = write(out_fd, buf, l);
if (r < 0)
return -errno;
return (ssize_t) l;
}
int read_full_file(const char *fn, char **contents, size_t *size) {
_cleanup_fclose_ FILE *f = NULL;
size_t n, l;
@ -168,7 +240,6 @@ int read_full_file(const char *fn, char **contents, size_t *size) {
buf[l] = 0;
*contents = buf;
buf = NULL;
if (size)
*size = l;

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@ -31,6 +31,7 @@ int write_string_file_atomic(const char *fn, const char *line);
int read_one_line_file(const char *fn, char **line);
int read_full_file(const char *fn, char **contents, size_t *size);
ssize_t sendfile_full(int out_fd, const char *fn);
int parse_env_file(const char *fname, const char *separator, ...) _sentinel_;
int load_env_file(const char *fname, const char *separator, char ***l);

View File

@ -5791,6 +5791,8 @@ void* greedy_realloc(void **p, size_t *allocated, size_t need) {
size_t a;
void *q;
assert(allocated);
if (*allocated >= need)
return *p;

View File

@ -3675,6 +3675,107 @@ static int show_all(
return 0;
}
static int cat(sd_bus *bus, char **args) {
int r = 0;
char **name;
_cleanup_free_ char *unit = NULL, *n = NULL;
assert(bus);
assert(args);
pager_open_if_enabled();
STRV_FOREACH(name, args+1) {
_cleanup_free_ char *fragment_path = NULL;
_cleanup_strv_free_ char **dropin_paths = NULL;
sd_bus_error error;
FILE *stdout;
char **path;
n = unit_name_mangle(*name);
if (!n)
return log_oom();
unit = unit_dbus_path_from_name(n);
if (!unit)
return log_oom();
if (need_daemon_reload(bus, n) > 0)
log_warning("Unit file of %s changed on disk. Run 'systemctl%s daemon-reload'.",
n, arg_scope == UNIT_FILE_SYSTEM ? "" : " --user");
r = sd_bus_get_property_string(
bus,
"org.freedesktop.systemd1",
unit,
"org.freedesktop.systemd1.Unit",
"FragmentPath",
&error,
&fragment_path);
if (r < 0) {
log_warning("Failed to get FragmentPath: %s", bus_error_message(&error, r));
continue;
}
if (isempty(fragment_path)) {
free(fragment_path);
fragment_path = NULL;
if (sd_bus_get_property_string(
bus,
"org.freedesktop.systemd1",
unit,
"org.freedesktop.systemd1.Unit",
"SourcePath",
&error,
&fragment_path) < 0) {
log_warning("Failed to get SourcePath: %s", bus_error_message(&error, r));
continue;
}
}
r = sd_bus_get_property_strv(
bus,
"org.freedesktop.systemd1",
unit,
"org.freedesktop.systemd1.Unit",
"DropInPaths",
&error,
&dropin_paths);
if (r < 0) {
log_warning("Failed to get DropInPaths: %s", bus_error_message(&error, r));
continue;
}
stdout = fdopen(STDOUT_FILENO, "a");
if (!isempty(fragment_path)) {
fprintf(stdout, "# %s\n", fragment_path);
fflush(stdout);
r = sendfile_full(STDOUT_FILENO, fragment_path);
if (r < 0) {
log_warning("Failed to cat %s: %s", fragment_path, strerror(-r));
continue;
}
}
STRV_FOREACH(path, dropin_paths) {
fprintf(stdout, "%s# %s\n",
isempty(fragment_path) && path == dropin_paths ? "" : "\n",
*path);
fflush(stdout);
r = sendfile_full(STDOUT_FILENO, *path);
if (r < 0) {
log_warning("Failed to cat %s: %s", *path, strerror(-r));
continue;
}
}
}
return r;
}
static int show(sd_bus *bus, char **args) {
int r, ret = 0;
bool show_properties, show_status, new_line = false;
@ -4707,6 +4808,7 @@ 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"
" cat [NAME...] Show files and drop-ins of one or more units\n"
" set-property [NAME] [ASSIGNMENT...]\n"
" Sets one or more properties of a unit\n"
" help [NAME...|PID...] Show manual for one or more units\n"
@ -5690,6 +5792,7 @@ static int systemctl_main(sd_bus *bus, int argc, char *argv[], int bus_error) {
{ "check", MORE, 2, check_unit_active },
{ "is-failed", MORE, 2, check_unit_failed },
{ "show", MORE, 1, show },
{ "cat", MORE, 2, cat },
{ "status", MORE, 1, show },
{ "help", MORE, 2, show },
{ "snapshot", LESS, 2, snapshot },