tools/sanity_check/systemtest.cpp

   1 /**
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  15  *
  16  * Set of functions to gather system information for the jack setup wizard.
  17  *
  18  * TODO: Test for rt prio availability
  19  *
  20  * @author Florian Faber, faber@faberman.de
  21  *
  22  **/
  23
  24 /** maximum number of groups a user can be a member of **/
  25 #define MAX_GROUPS 100
  26
  27 #include <fcntl.h>
  28
  29 #include <stdlib.h>
  30 #include <sys/types.h>
  31 #include <unistd.h>
  32 #include <grp.h>
  33
  34 #include <sched.h>
  35 #include <string.h>
  36
  37 #include <sys/time.h>
  38 #include <sys/resource.h>
  39
  40 #include <stdio.h>
  41 #include <errno.h>
  42
  43 #include "systemtest.h"
  44
  45 /**
  46  * This function checks for the existence of known frequency scaling mechanisms
  47  * in this system by testing for the availability of scaling governors/
  48  *
  49  * @returns 0 if the system has no frequency scaling capabilities non-0 otherwise.
  50  **/
  51 int system_has_frequencyscaling() {
  52   int fd;
  53
  54   fd = open("/sys/devices/system/cpu/cpu0/cpufreq/scaling_available_governors", O_RDONLY);
  55
  56   if (-1==fd) {
  57     return 0;
  58   }
  59
  60   (void) close(fd);
  61
  62   return 1;
  63 }
  64
  65
  66 static int read_string(char* filename, char* buf, size_t buflen) {
  67   int fd;
  68   ssize_t r=-1;
  69
  70   memset (buf, 0, buflen);
  71
  72   fd = open (filename, O_RDONLY);
  73   if (-1<fd) {
  74     r = read (fd, buf, buflen-1);
  75     (void) close(fd);
  76
  77     if (-1==r) {
  78       fprintf(stderr, "Error while reading \"%s\": %s\n", filename, strerror(errno));
  79       exit(EXIT_FAILURE);
  80     }
  81   }
  82
  83   return (int) r;
  84 }
  85
  86
  87 static int read_int(char* filename, int* value) {
  88   char buf[20];
  89
  90   if (0<read_string(filename, buf, 20)) {
  91                 return (1==sscanf(buf, "%d", value));
  92   }
  93
  94   return 0;
  95 }
  96
  97
  98 /**
  99  * This function determines wether any CPU core uses a variable clock speed if frequency
 100  * scaling is available. If the governor for all cores is either "powersave" or
 101  * "performance", the CPU frequency can be assumed to be static. This is also the case
 102  * if scaling_min_freq and scaling_max_freq are set to the same value.
 103  *
 104  * @returns 0 if system doesn't use frequency scaling at the moment, non-0 otherwise
 105  **/
 106 int system_uses_frequencyscaling() {
 107   int cpu=0, done=0, min, max;
 108   char filename[256], buf[256];
 109
 110   while (!done) {
 111           (void) snprintf(filename, 256, "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_governor", cpu);
 112           if (0<read_string(filename, buf, 256)) {
 113                   if ((0!=strncmp("performance", buf, 11)) &&
 114                       (0!=strncmp("powersafe", buf, 9))) {
 115                           // So it's neither the "performance" nor the "powersafe" governor
 116                           (void) snprintf(filename, 256, "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_min_freq", cpu);
 117                           if (read_int(filename, &min)) {
 118                                   (void) snprintf(filename, 256, "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_max_freq", cpu);
 119                                   if (read_int(filename, &max)) {
 120                                           if (min!=max) {
 121                                                   // wrong governor AND different frequency limits -> scaling
 122                                                   return 1;
 123                                           }
 124                                   }
 125                           }
 126                   }
 127           } else {
 128                   // couldn't open file -> no more cores
 129                   done = 1;
 130           }
 131           cpu++;
 132   }
 133
 134   // couldn't find anything that points to scaling
 135   return 0;
 136 }
 137
 138
 139 static gid_t get_group_by_name(const char* name) {
 140   struct group* grp;
 141         gid_t res = 0;
 142
 143   while ((0==res) && (NULL != (grp = getgrent()))) {
 144     if (0==strcmp(name, grp->gr_name)) {
 145       res = grp->gr_gid;
 146     }
 147   }
 148
 149         endgrent();
 150
 151   return res;
 152 }
 153
 154 /**
 155  * Tests wether the owner of this process is in the group 'name'.
 156  *
 157  * @returns 0 if the owner of this process is not in the group, non-0 otherwise
 158  **/
 159 int system_user_in_group(const char *name) {
 160   gid_t* list = (gid_t*) malloc(MAX_GROUPS * sizeof(gid_t));
 161   int num_groups, i=0, found=0;
 162         unsigned int gid;
 163
 164   if (NULL==list) {
 165     perror("Cannot allocate group list structure");
 166     exit(EXIT_FAILURE);
 167   }
 168
 169   gid = get_group_by_name(name);
 170   if (0==gid) {
 171     fprintf(stderr, "No %s group found\n", name);
 172     return 0;
 173   }
 174
 175   num_groups = getgroups(MAX_GROUPS, list);
 176
 177   while (i<num_groups) {
 178     if (list[i]==gid) {
 179       found = 1;
 180       i = num_groups;
 181     }
 182
 183     i++;
 184   }
 185
 186   free(list);
 187
 188   return found;
 189 }
 190
 191
 192 /***
 193  * Checks for a definition in /etc/security/limits.conf that looks
 194  * as if it allows RT scheduling priority.
 195  *
 196  * @returns 1 if there appears to be such a line
 197  **/
 198 int system_has_rtprio_limits_conf ()
 199 {
 200         const char* limits = "/etc/security/limits.conf";
 201         char cmd[100];
 202
 203         snprintf (cmd, sizeof (cmd), "grep -q 'rtprio *[0-9][0-9]*' %s", limits);
 204         if (system (cmd) == 0) {
 205                 return 1;
 206         }
 207         return 0;
 208 }
 209
 210
 211 /**
 212  * Checks for the existence of the 'audio' group on this system
 213  *
 214  * @returns 0 if there is no 'audio' group, the group id otherwise
 215  **/
 216 int system_has_audiogroup() {
 217         return get_group_by_name("audio") || get_group_by_name ("jackuser");
 218 }
 219
 220
 221 /**
 222  * Checks for the existence of 'groupname' on this system
 223  *
 224  * @returns 0 if there is no group, the group id otherwise
 225  **/
 226 int system_has_group(const char * name) {
 227         return get_group_by_name(name);
 228 }
 229
 230
 231 /**
 232  * Tests wether the owner of this process is in the 'audio' group.
 233  *
 234  * @returns 0 if the owner of this process is not in the audio group, non-0 otherwise
 235  **/
 236 int system_user_in_audiogroup() {
 237         return system_user_in_group("audio") || system_user_in_group("jackuser");
 238 }
 239
 240
 241 /**
 242  * Determines wether the owner of this process can enable rt priority.
 243  *
 244  * @returns 0 if this process can not be switched to rt prio, non-0 otherwise
 245  **/
 246 int system_user_can_rtprio() {
 247   int min_prio;
 248   struct sched_param schparam;
 249
 250   memset(&schparam, 0, sizeof(struct sched_param));
 251
 252   if (-1 == (min_prio = sched_get_priority_min(SCHED_FIFO))) {
 253     perror("sched_get_priority");
 254     exit(EXIT_FAILURE);
 255   }
 256   schparam.sched_priority = min_prio;
 257
 258   if (0 == sched_setscheduler(0, SCHED_FIFO, &schparam)) {
 259     // TODO: restore previous state
 260     schparam.sched_priority = 0;
 261     if (0 != sched_setscheduler(0, SCHED_OTHER, &schparam)) {
 262       perror("sched_setscheduler");
 263       exit(EXIT_FAILURE);
 264     }
 265     return 1;
 266   }
 267
 268   return 0;
 269 }
 270
 271
 272 long long unsigned int system_memlock_amount() {
 273         struct rlimit limits;
 274
 275         if (-1==getrlimit(RLIMIT_MEMLOCK, &limits)) {
 276                 perror("getrlimit on RLIMIT_MEMLOCK");
 277                 exit(EXIT_FAILURE);
 278         }
 279
 280         return limits.rlim_max;
 281 }
 282
 283
 284 /**
 285  * Checks wether the memlock limit is unlimited
 286  *
 287  * @returns - 0 if the memlock limit is limited, non-0 otherwise
 288  **/
 289 int system_memlock_is_unlimited() {
 290         return ((RLIM_INFINITY==system_memlock_amount())?1:0);
 291 }
 292
 293
 294 long long unsigned int system_available_physical_mem() {
 295         char buf[256];
 296         long long unsigned int res = 0;
 297
 298         if (0<read_string((char*)"/proc/meminfo", buf, sizeof (buf))) {
 299                 if (strncmp (buf, "MemTotal:", 9) == 0) {
 300                         if (sscanf (buf, "%*s %llu", &res) != 1) {
 301                                 perror ("parse error in /proc/meminfo");
 302                         }
 303                 }
 304         } else {
 305                 perror("read from /proc/meminfo");
 306         }
 307
 308         return res*1024;
 309 }
 310
 311
 312 /**
 313  * Gets the version of the currently running kernel. The string
 314  * returned has to be freed by the caller.
 315  *
 316  * @returns String with the full version of the kernel
 317  **/
 318 char* system_kernel_version() {
 319   return NULL;
 320 }
 321
 322
 323
 324 char* system_get_username() {
 325   char* res = NULL;
 326   char* name = NULL;
 327
 328   if ((name = getlogin())) {
 329     res = strdup(name);
 330   }
 331
 332   return res;
 333 }