release/src/router/nginx/src/os/unix/ngx_daemon.c

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  * Copyright (C) Nginx, Inc.
   5  */
   6
   7
   8 #include <ngx_config.h>
   9 #include <ngx_core.h>
  10
  11
  12 ngx_int_t
  13 ngx_daemon(ngx_log_t *log)
  14 {
  15     int  fd;
  16
  17     switch (fork()) {
  18     case -1:
  19         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "fork() failed");
  20         return NGX_ERROR;
  21
  22     case 0:
  23         break;
  24
  25     default:
  26         exit(0);
  27     }
  28
  29     ngx_pid = ngx_getpid();
  30
  31     if (setsid() == -1) {
  32         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "setsid() failed");
  33         return NGX_ERROR;
  34     }
  35
  36     umask(0);
  37
  38     fd = open("/dev/null", O_RDWR);
  39     if (fd == -1) {
  40         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
  41                       "open(\"/dev/null\") failed");
  42         return NGX_ERROR;
  43     }
  44
  45     if (dup2(fd, STDIN_FILENO) == -1) {
  46         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "dup2(STDIN) failed");
  47         return NGX_ERROR;
  48     }
  49
  50     if (dup2(fd, STDOUT_FILENO) == -1) {
  51         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "dup2(STDOUT) failed");
  52         return NGX_ERROR;
  53     }
  54
  55 #if 0
  56     if (dup2(fd, STDERR_FILENO) == -1) {
  57         ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "dup2(STDERR) failed");
  58         return NGX_ERROR;
  59     }
  60 #endif
  61
  62     if (fd > STDERR_FILENO) {
  63         if (close(fd) == -1) {
  64             ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "close() failed");
  65             return NGX_ERROR;
  66         }
  67     }
  68
  69     return NGX_OK;
  70 }