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 <sys/types.h>
  14 #include <unistd.h>
  15
  16 #include <rte_common.h>
  17 #include <rte_log.h>
  18
  19 #include "eal_private.h"
  20 #include "eal_filesystem.h"
  21
  22 int eal_create_runtime_dir(void)
  23 {
  24         const char *directory;
  25         char run_dir[PATH_MAX];
  26         char tmp[PATH_MAX];
  27         int ret;
  28
  29         /* from RuntimeDirectory= see systemd.exec */
  30         directory = getenv("RUNTIME_DIRECTORY");
  31         if (directory == NULL) {
  32                 /*
  33                  * Used standard convention defined in
  34                  * XDG Base Directory Specification and
  35                  * Filesystem Hierarchy Standard.
  36                  */
  37                 if (getuid() == 0)
  38                         directory = "/var/run";
  39                 else
  40                         directory = getenv("XDG_RUNTIME_DIR") ? : "/tmp";
  41         }
  42
  43         /* create DPDK subdirectory under runtime dir */
  44         ret = snprintf(tmp, sizeof(tmp), "%s/dpdk", directory);
  45         if (ret < 0 || ret == sizeof(tmp)) {
  46                 RTE_LOG(ERR, EAL, "Error creating DPDK runtime path name\n");
  47                 return -1;
  48         }
  49
  50         /* create prefix-specific subdirectory under DPDK runtime dir */
  51         ret = snprintf(run_dir, sizeof(run_dir), "%s/%s",
  52                         tmp, eal_get_hugefile_prefix());
  53         if (ret < 0 || ret == sizeof(run_dir)) {
  54                 RTE_LOG(ERR, EAL, "Error creating prefix-specific runtime path name\n");
  55                 return -1;
  56         }
  57
  58         /* create the path if it doesn't exist. no "mkdir -p" here, so do it
  59          * step by step.
  60          */
  61         ret = mkdir(tmp, 0700);
  62         if (ret < 0 && errno != EEXIST) {
  63                 RTE_LOG(ERR, EAL, "Error creating '%s': %s\n",
  64                         tmp, strerror(errno));
  65                 return -1;
  66         }
  67
  68         ret = mkdir(run_dir, 0700);
  69         if (ret < 0 && errno != EEXIST) {
  70                 RTE_LOG(ERR, EAL, "Error creating '%s': %s\n",
  71                         run_dir, strerror(errno));
  72                 return -1;
  73         }
  74
  75         if (eal_set_runtime_dir(run_dir))
  76                 return -1;
  77
  78         return 0;
  79 }
  80
  81 /* parse a sysfs (or other) file containing one integer value */
  82 int eal_parse_sysfs_value(const char *filename, unsigned long *val)
  83 {
  84         FILE *f;
  85         char buf[BUFSIZ];
  86         char *end = NULL;
  87
  88         if ((f = fopen(filename, "r")) == NULL) {
  89                 RTE_LOG(ERR, EAL, "%s(): cannot open sysfs value %s\n",
  90                         __func__, filename);
  91                 return -1;
  92         }
  93
  94         if (fgets(buf, sizeof(buf), f) == NULL) {
  95                 RTE_LOG(ERR, EAL, "%s(): cannot read sysfs value %s\n",
  96                         __func__, filename);
  97                 fclose(f);
  98                 return -1;
  99         }
 100         *val = strtoul(buf, &end, 0);
 101         if ((buf[0] == '\0') || (end == NULL) || (*end != '\n')) {
 102                 RTE_LOG(ERR, EAL, "%s(): cannot parse sysfs value %s\n",
 103                                 __func__, filename);
 104                 fclose(f);
 105                 return -1;
 106         }
 107         fclose(f);
 108         return 0;
 109 }