src/portable/portabled-operation.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include "alloc-util.h"
   4 #include "fd-util.h"
   5 #include "portabled-operation.h"
   6 #include "process-util.h"
   7
   8 static int operation_done(sd_event_source *s, const siginfo_t *si, void *userdata) {
   9         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
  10         Operation *o = userdata;
  11         int r;
  12
  13         assert(o);
  14         assert(si);
  15
  16         log_debug("Operating " PID_FMT " is now complete with code=%s status=%i",
  17                   o->pid,
  18                   sigchld_code_to_string(si->si_code), si->si_status);
  19
  20         o->pid = 0;
  21
  22         if (si->si_code != CLD_EXITED) {
  23                 r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Child died abnormally.");
  24                 goto fail;
  25         }
  26
  27         if (si->si_status == EXIT_SUCCESS)
  28                 r = 0;
  29         else if (read(o->errno_fd, &r, sizeof(r)) != sizeof(r)) { /* Try to acquire error code for failed operation */
  30                 r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Child failed.");
  31                 goto fail;
  32         }
  33
  34         if (o->done) {
  35                 /* A completion routine is set for this operation, call it. */
  36                 r = o->done(o, r, &error);
  37                 if (r < 0) {
  38                         if (!sd_bus_error_is_set(&error))
  39                                 sd_bus_error_set_errno(&error, r);
  40
  41                         goto fail;
  42                 }
  43
  44         } else {
  45                 /* The default operation when done is to simply return an error on failure or an empty success
  46                  * message on success. */
  47                 if (r < 0) {
  48                         sd_bus_error_set_errno(&error, r);
  49                         goto fail;
  50                 }
  51
  52                 r = sd_bus_reply_method_return(o->message, NULL);
  53                 if (r < 0)
  54                         log_error_errno(r, "Failed to reply to message: %m");
  55         }
  56
  57         operation_free(o);
  58         return 0;
  59
  60 fail:
  61         r = sd_bus_reply_method_error(o->message, &error);
  62         if (r < 0)
  63                 log_error_errno(r, "Failed to reply to message: %m");
  64
  65         operation_free(o);
  66         return 0;
  67 }
  68
  69 int operation_new(Manager *manager, pid_t child, sd_bus_message *message, int errno_fd, Operation **ret) {
  70         Operation *o;
  71         int r;
  72
  73         assert(manager);
  74         assert(child > 1);
  75         assert(message);
  76         assert(errno_fd >= 0);
  77
  78         o = new0(Operation, 1);
  79         if (!o)
  80                 return -ENOMEM;
  81
  82         o->extra_fd = -1;
  83
  84         r = sd_event_add_child(manager->event, &o->event_source, child, WEXITED, operation_done, o);
  85         if (r < 0) {
  86                 free(o);
  87                 return r;
  88         }
  89
  90         o->pid = child;
  91         o->message = sd_bus_message_ref(message);
  92         o->errno_fd = errno_fd;
  93
  94         LIST_PREPEND(operations, manager->operations, o);
  95         manager->n_operations++;
  96         o->manager = manager;
  97
  98         log_debug("Started new operation " PID_FMT ".", child);
  99
 100         /* At this point we took ownership of both the child and the errno file descriptor! */
 101
 102         if (ret)
 103                 *ret = o;
 104
 105         return 0;
 106 }
 107
 108 Operation *operation_free(Operation *o) {
 109         if (!o)
 110                 return NULL;
 111
 112         sd_event_source_unref(o->event_source);
 113
 114         safe_close(o->errno_fd);
 115         safe_close(o->extra_fd);
 116
 117         if (o->pid > 1)
 118                 (void) sigkill_wait(o->pid);
 119
 120         sd_bus_message_unref(o->message);
 121
 122         if (o->manager) {
 123                 LIST_REMOVE(operations, o->manager->operations, o);
 124                 o->manager->n_operations--;
 125         }
 126
 127         return mfree(o);
 128 }