lib/eal/unix/eal_filesystem.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2018 Intel Corporation.
   3  * Copyright(c) 2012-2014 6WIND S.A.
   4  */
   5
   6 #include <errno.h>
   7 #include <limits.h>
   8 #include <stddef.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <sys/stat.h>
  13 #include <unistd.h>
  14
  15 #include <rte_log.h>
  16
  17 #include "eal_private.h"
  18 #include "eal_filesystem.h"
  19
  20 int eal_create_runtime_dir(void)
  21 {
  22         const char *directory;
  23         char run_dir[PATH_MAX];
  24         char tmp[PATH_MAX];
  25         int ret;
  26
  27         /* from RuntimeDirectory= see systemd.exec */
  28         directory = getenv("RUNTIME_DIRECTORY");
  29         if (directory == NULL) {
  30                 /*
  31                  * Used standard convention defined in
  32                  * XDG Base Directory Specification and
  33                  * Filesystem Hierarchy Standard.
  34                  */
  35                 if (getuid() == 0)
  36                         directory = "/var/run";
  37                 else
  38                         directory = getenv("XDG_RUNTIME_DIR") ? : "/tmp";
  39         }
  40
  41         /* create DPDK subdirectory under runtime dir */
  42         ret = snprintf(tmp, sizeof(tmp), "%s/dpdk", directory);
  43         if (ret < 0 || ret == sizeof(tmp)) {
  44                 RTE_LOG(ERR, EAL, "Error creating DPDK runtime path name\n");
  45                 return -1;
  46         }
  47
  48         /* create prefix-specific subdirectory under DPDK runtime dir */
  49         ret = snprintf(run_dir, sizeof(run_dir), "%s/%s",
  50                         tmp, eal_get_hugefile_prefix());
  51         if (ret < 0 || ret == sizeof(run_dir)) {
  52                 RTE_LOG(ERR, EAL, "Error creating prefix-specific runtime path name\n");
  53                 return -1;
  54         }
  55
  56         /* create the path if it doesn't exist. no "mkdir -p" here, so do it
  57          * step by step.
  58          */
  59         ret = mkdir(tmp, 0700);
  60         if (ret < 0 && errno != EEXIST) {
  61                 RTE_LOG(ERR, EAL, "Error creating '%s': %s\n",
  62                         tmp, strerror(errno));
  63                 return -1;
  64         }
  65
  66         ret = mkdir(run_dir, 0700);
  67         if (ret < 0 && errno != EEXIST) {
  68                 RTE_LOG(ERR, EAL, "Error creating '%s': %s\n",
  69                         run_dir, strerror(errno));
  70                 return -1;
  71         }
  72
  73         if (eal_set_runtime_dir(run_dir))
  74                 return -1;
  75
  76         return 0;
  77 }
  78
  79 /* parse a sysfs (or other) file containing one integer value */
  80 int eal_parse_sysfs_value(const char *filename, unsigned long *val)
  81 {
  82         FILE *f;
  83         char buf[BUFSIZ];
  84         char *end = NULL;
  85
  86         if ((f = fopen(filename, "r")) == NULL) {
  87                 RTE_LOG(ERR, EAL, "%s(): cannot open sysfs value %s\n",
  88                         __func__, filename);
  89                 return -1;
  90         }
  91
  92         if (fgets(buf, sizeof(buf), f) == NULL) {
  93                 RTE_LOG(ERR, EAL, "%s(): cannot read sysfs value %s\n",
  94                         __func__, filename);
  95                 fclose(f);
  96                 return -1;
  97         }
  98         *val = strtoul(buf, &end, 0);
  99         if ((buf[0] == '\0') || (end == NULL) || (*end != '\n')) {
 100                 RTE_LOG(ERR, EAL, "%s(): cannot parse sysfs value %s\n",
 101                                 __func__, filename);
 102                 fclose(f);
 103                 return -1;
 104         }
 105         fclose(f);
 106         return 0;
 107 }