src/portable/portabled-operation.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <unistd.h>
   4
   5 #include "alloc-util.h"
   6 #include "fd-util.h"
   7 #include "portabled-operation.h"
   8 #include "process-util.h"
   9
  10 static int operation_done(sd_event_source *s, const siginfo_t *si, void *userdata) {
  11         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
  12         Operation *o = ASSERT_PTR(userdata);
  13         int r;
  14
  15         assert(si);
  16
  17         log_debug("Operating " PID_FMT " is now complete with code=%s status=%i",
  18                   o->pid,
  19                   sigchld_code_to_string(si->si_code), si->si_status);
  20
  21         o->pid = 0;
  22
  23         if (si->si_code != CLD_EXITED) {
  24                 r = sd_bus_error_set(&error, SD_BUS_ERROR_FAILED, "Child died abnormally.");
  25                 goto fail;
  26         }
  27
  28         if (si->si_status == EXIT_SUCCESS)
  29                 r = 0;
  30         else if (read(o->errno_fd, &r, sizeof(r)) != sizeof(r)) { /* Try to acquire error code for failed operation */
  31                 r = sd_bus_error_set(&error, SD_BUS_ERROR_FAILED, "Child failed.");
  32                 goto fail;
  33         }
  34
  35         if (o->done) {
  36                 /* A completion routine is set for this operation, call it. */
  37                 r = o->done(o, r, &error);
  38                 if (r < 0) {
  39                         if (!sd_bus_error_is_set(&error))
  40                                 sd_bus_error_set_errno(&error, r);
  41
  42                         goto fail;
  43                 }
  44
  45         } else {
  46                 /* The default operation when done is to simply return an error on failure or an empty success
  47                  * message on success. */
  48                 if (r < 0) {
  49                         sd_bus_error_set_errno(&error, r);
  50                         goto fail;
  51                 }
  52
  53                 r = sd_bus_reply_method_return(o->message, NULL);
  54                 if (r < 0)
  55                         log_error_errno(r, "Failed to reply to message: %m");
  56         }
  57
  58         operation_free(o);
  59         return 0;
  60
  61 fail:
  62         r = sd_bus_reply_method_error(o->message, &error);
  63         if (r < 0)
  64                 log_error_errno(r, "Failed to reply to message: %m");
  65
  66         operation_free(o);
  67         return 0;
  68 }
  69
  70 int operation_new(Manager *manager, pid_t child, sd_bus_message *message, int errno_fd, Operation **ret) {
  71         Operation *o;
  72         int r;
  73
  74         assert(manager);
  75         assert(child > 1);
  76         assert(message);
  77         assert(errno_fd >= 0);
  78
  79         o = new0(Operation, 1);
  80         if (!o)
  81                 return -ENOMEM;
  82
  83         o->extra_fd = -1;
  84
  85         r = sd_event_add_child(manager->event, &o->event_source, child, WEXITED, operation_done, o);
  86         if (r < 0) {
  87                 free(o);
  88                 return r;
  89         }
  90
  91         o->pid = child;
  92         o->message = sd_bus_message_ref(message);
  93         o->errno_fd = errno_fd;
  94
  95         LIST_PREPEND(operations, manager->operations, o);
  96         manager->n_operations++;
  97         o->manager = manager;
  98
  99         log_debug("Started new operation " PID_FMT ".", child);
 100
 101         /* At this point we took ownership of both the child and the errno file descriptor! */
 102
 103         if (ret)
 104                 *ret = o;
 105
 106         return 0;
 107 }
 108
 109 Operation *operation_free(Operation *o) {
 110         if (!o)
 111                 return NULL;
 112
 113         sd_event_source_unref(o->event_source);
 114
 115         safe_close(o->errno_fd);
 116         safe_close(o->extra_fd);
 117
 118         if (o->pid > 1)
 119                 (void) sigkill_wait(o->pid);
 120
 121         sd_bus_message_unref(o->message);
 122
 123         if (o->manager) {
 124                 LIST_REMOVE(operations, o->manager->operations, o);
 125                 o->manager->n_operations--;
 126         }
 127
 128         return mfree(o);
 129 }