src/shared/install-printf.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2013 Zbigniew Jędrzejewski-Szmek
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <stdlib.h>
  23
  24 #include "alloc-util.h"
  25 #include "formats-util.h"
  26 #include "install-printf.h"
  27 #include "specifier.h"
  28 #include "unit-name.h"
  29 #include "user-util.h"
  30 #include "util.h"
  31
  32 static int specifier_prefix_and_instance(char specifier, void *data, void *userdata, char **ret) {
  33         UnitFileInstallInfo *i = userdata;
  34
  35         assert(i);
  36
  37         return unit_name_to_prefix_and_instance(i->name, ret);
  38 }
  39
  40 static int specifier_prefix(char specifier, void *data, void *userdata, char **ret) {
  41         UnitFileInstallInfo *i = userdata;
  42
  43         assert(i);
  44
  45         return unit_name_to_prefix(i->name, ret);
  46 }
  47
  48 static int specifier_instance(char specifier, void *data, void *userdata, char **ret) {
  49         UnitFileInstallInfo *i = userdata;
  50         char *instance;
  51         int r;
  52
  53         assert(i);
  54
  55         r = unit_name_to_instance(i->name, &instance);
  56         if (r < 0)
  57                 return r;
  58
  59         if (!instance) {
  60                 instance = strdup("");
  61                 if (!instance)
  62                         return -ENOMEM;
  63         }
  64
  65         *ret = instance;
  66         return 0;
  67 }
  68
  69 static int specifier_user_name(char specifier, void *data, void *userdata, char **ret) {
  70         UnitFileInstallInfo *i = userdata;
  71         const char *username;
  72         _cleanup_free_ char *tmp = NULL;
  73         char *printed = NULL;
  74
  75         assert(i);
  76
  77         if (i->user)
  78                 username = i->user;
  79         else
  80                 /* get USER env from env or our own uid */
  81                 username = tmp = getusername_malloc();
  82
  83         switch (specifier) {
  84         case 'u':
  85                 printed = strdup(username);
  86                 break;
  87         case 'U': {
  88                 /* fish username from passwd */
  89                 uid_t uid;
  90                 int r;
  91
  92                 r = get_user_creds(&username, &uid, NULL, NULL, NULL);
  93                 if (r < 0)
  94                         return r;
  95
  96                 if (asprintf(&printed, UID_FMT, uid) < 0)
  97                         return -ENOMEM;
  98                 break;
  99         }}
 100
 101
 102         *ret = printed;
 103         return 0;
 104 }
 105
 106
 107 int install_full_printf(UnitFileInstallInfo *i, const char *format, char **ret) {
 108
 109         /* This is similar to unit_full_printf() but does not support
 110          * anything path-related.
 111          *
 112          * %n: the full id of the unit                 (foo@bar.waldo)
 113          * %N: the id of the unit without the suffix   (foo@bar)
 114          * %p: the prefix                              (foo)
 115          * %i: the instance                            (bar)
 116
 117          * %U the UID of the configured user or running user
 118          * %u the username of the configured user or running user
 119          * %m the machine ID of the running system
 120          * %H the host name of the running system
 121          * %b the boot ID of the running system
 122          * %v `uname -r` of the running system
 123          */
 124
 125         const Specifier table[] = {
 126                 { 'n', specifier_string,              i->name },
 127                 { 'N', specifier_prefix_and_instance, NULL },
 128                 { 'p', specifier_prefix,              NULL },
 129                 { 'i', specifier_instance,            NULL },
 130
 131                 { 'U', specifier_user_name,           NULL },
 132                 { 'u', specifier_user_name,           NULL },
 133
 134                 { 'm', specifier_machine_id,          NULL },
 135                 { 'H', specifier_host_name,           NULL },
 136                 { 'b', specifier_boot_id,             NULL },
 137                 { 'v', specifier_kernel_release,      NULL },
 138                 {}
 139         };
 140
 141         assert(i);
 142         assert(format);
 143         assert(ret);
 144
 145         return specifier_printf(format, table, i, ret);
 146 }