Adding upstream version 3.2.2.upstream/3.2.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2302 insertions, 0 deletions

diff --git a/linux/LinuxProcessList.c b/linux/LinuxProcessList.c
new file mode 100644
index 0000000..eca9459
--- /dev/null
+++ b/linux/LinuxProcessList.c
@@ -0,0 +1,2302 @@
+/*
+htop - LinuxProcessList.c
+(C) 2014 Hisham H. Muhammad
+Released under the GNU GPLv2+, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include "config.h" // IWYU pragma: keep
+
+#include "linux/LinuxProcessList.h"
+
+#include <assert.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <math.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#ifdef HAVE_DELAYACCT
+#include <linux/netlink.h>
+#include <linux/taskstats.h>
+#include <netlink/attr.h>
+#include <netlink/handlers.h>
+#include <netlink/msg.h>
+#include <netlink/netlink.h>
+#include <netlink/socket.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/ctrl.h>
+#endif
+
+#include "Compat.h"
+#include "CRT.h"
+#include "Macros.h"
+#include "Object.h"
+#include "Process.h"
+#include "Settings.h"
+#include "XUtils.h"
+#include "linux/CGroupUtils.h"
+#include "linux/LinuxProcess.h"
+#include "linux/Platform.h" // needed for GNU/hurd to get PATH_MAX  // IWYU pragma: keep
+
+#if defined(MAJOR_IN_MKDEV)
+#include <sys/mkdev.h>
+#elif defined(MAJOR_IN_SYSMACROS)
+#include <sys/sysmacros.h>
+#endif
+
+#ifdef HAVE_SENSORS_SENSORS_H
+#include "LibSensors.h"
+#endif
+
+#ifndef O_PATH
+#define O_PATH         010000000 // declare for ancient glibc versions
+#endif
+
+/* Not exposed yet. Defined at include/linux/sched.h */
+#ifndef PF_KTHREAD
+#define PF_KTHREAD 0x00200000
+#endif
+
+static long long btime = -1;
+
+static long jiffy;
+
+static FILE* fopenat(openat_arg_t openatArg, const char* pathname, const char* mode) {
+   assert(String_eq(mode, "r")); /* only currently supported mode */
+
+   int fd = Compat_openat(openatArg, pathname, O_RDONLY);
+   if (fd < 0)
+      return NULL;
+
+   FILE* stream = fdopen(fd, mode);
+   if (!stream)
+      close(fd);
+
+   return stream;
+}
+
+static int sortTtyDrivers(const void* va, const void* vb) {
+   const TtyDriver* a = (const TtyDriver*) va;
+   const TtyDriver* b = (const TtyDriver*) vb;
+
+   int r = SPACESHIP_NUMBER(a->major, b->major);
+   if (r)
+      return r;
+
+   return SPACESHIP_NUMBER(a->minorFrom, b->minorFrom);
+}
+
+static void LinuxProcessList_initTtyDrivers(LinuxProcessList* this) {
+   TtyDriver* ttyDrivers;
+
+   char buf[16384];
+   ssize_t r = xReadfile(PROCTTYDRIVERSFILE, buf, sizeof(buf));
+   if (r < 0)
+      return;
+
+   int numDrivers = 0;
+   int allocd = 10;
+   ttyDrivers = xMallocArray(allocd, sizeof(TtyDriver));
+   char* at = buf;
+   while (*at != '\0') {
+      at = strchr(at, ' ');    // skip first token
+      while (*at == ' ') at++; // skip spaces
+      const char* token = at;  // mark beginning of path
+      at = strchr(at, ' ');    // find end of path
+      *at = '\0'; at++;        // clear and skip
+      ttyDrivers[numDrivers].path = xStrdup(token); // save
+      while (*at == ' ') at++; // skip spaces
+      token = at;              // mark beginning of major
+      at = strchr(at, ' ');    // find end of major
+      *at = '\0'; at++;        // clear and skip
+      ttyDrivers[numDrivers].major = atoi(token); // save
+      while (*at == ' ') at++; // skip spaces
+      token = at;              // mark beginning of minorFrom
+      while (*at >= '0' && *at <= '9') at++; //find end of minorFrom
+      if (*at == '-') {        // if has range
+         *at = '\0'; at++;        // clear and skip
+         ttyDrivers[numDrivers].minorFrom = atoi(token); // save
+         token = at;              // mark beginning of minorTo
+         at = strchr(at, ' ');    // find end of minorTo
+         *at = '\0'; at++;        // clear and skip
+         ttyDrivers[numDrivers].minorTo = atoi(token); // save
+      } else {                 // no range
+         *at = '\0'; at++;        // clear and skip
+         ttyDrivers[numDrivers].minorFrom = atoi(token); // save
+         ttyDrivers[numDrivers].minorTo = atoi(token); // save
+      }
+      at = strchr(at, '\n');   // go to end of line
+      at++;                    // skip
+      numDrivers++;
+      if (numDrivers == allocd) {
+         allocd += 10;
+         ttyDrivers = xReallocArray(ttyDrivers, allocd, sizeof(TtyDriver));
+      }
+   }
+   numDrivers++;
+   ttyDrivers = xRealloc(ttyDrivers, sizeof(TtyDriver) * numDrivers);
+   ttyDrivers[numDrivers - 1].path = NULL;
+   qsort(ttyDrivers, numDrivers - 1, sizeof(TtyDriver), sortTtyDrivers);
+   this->ttyDrivers = ttyDrivers;
+}
+
+#ifdef HAVE_DELAYACCT
+
+static void LinuxProcessList_initNetlinkSocket(LinuxProcessList* this) {
+   this->netlink_socket = nl_socket_alloc();
+   if (this->netlink_socket == NULL) {
+      return;
+   }
+   if (nl_connect(this->netlink_socket, NETLINK_GENERIC) < 0) {
+      return;
+   }
+   this->netlink_family = genl_ctrl_resolve(this->netlink_socket, TASKSTATS_GENL_NAME);
+}
+
+#endif
+
+static unsigned int scanAvailableCPUsFromCPUinfo(LinuxProcessList* this) {
+   FILE* file = fopen(PROCCPUINFOFILE, "r");
+   if (file == NULL)
+      return this->super.existingCPUs;
+
+   unsigned int availableCPUs = 0;
+
+   while (!feof(file)) {
+      char buffer[PROC_LINE_LENGTH];
+
+      if (fgets(buffer, PROC_LINE_LENGTH, file) == NULL)
+         break;
+
+      if (String_startsWith(buffer, "processor"))
+         availableCPUs++;
+   }
+
+   fclose(file);
+
+   return availableCPUs ? availableCPUs : 1;
+}
+
+static void LinuxProcessList_updateCPUcount(ProcessList* super) {
+   /* Similar to get_nprocs_conf(3) / _SC_NPROCESSORS_CONF
+    * https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/getsysstats.c;hb=HEAD
+    */
+
+   LinuxProcessList* this = (LinuxProcessList*) super;
+   unsigned int existing = 0, active = 0;
+
+   // Initialize the cpuData array before anything else.
+   if (!this->cpuData) {
+      this->cpuData = xCalloc(2, sizeof(CPUData));
+      this->cpuData[0].online = true; /* average is always "online" */
+      this->cpuData[1].online = true;
+      super->activeCPUs = 1;
+      super->existingCPUs = 1;
+   }
+
+   DIR* dir = opendir("/sys/devices/system/cpu");
+   if (!dir)
+      return;
+
+   unsigned int currExisting = super->existingCPUs;
+
+   const struct dirent* entry;
+   while ((entry = readdir(dir)) != NULL) {
+      if (entry->d_type != DT_DIR && entry->d_type != DT_UNKNOWN)
+         continue;
+
+      if (!String_startsWith(entry->d_name, "cpu"))
+         continue;
+
+      char* endp;
+      unsigned long int id = strtoul(entry->d_name + 3, &endp, 10);
+      if (id == ULONG_MAX || endp == entry->d_name + 3 || *endp != '\0')
+         continue;
+
+#ifdef HAVE_OPENAT
+      int cpuDirFd = openat(dirfd(dir), entry->d_name, O_DIRECTORY | O_PATH | O_NOFOLLOW);
+      if (cpuDirFd < 0)
+         continue;
+#else
+      char cpuDirFd[4096];
+      xSnprintf(cpuDirFd, sizeof(cpuDirFd), "/sys/devices/system/cpu/%s", entry->d_name);
+#endif
+
+      existing++;
+
+      /* readdir() iterates with no specific order */
+      unsigned int max = MAXIMUM(existing, id + 1);
+      if (max > currExisting) {
+         this->cpuData = xReallocArrayZero(this->cpuData, currExisting ? (currExisting + 1) : 0, max + /* aggregate */ 1, sizeof(CPUData));
+         this->cpuData[0].online = true; /* average is always "online" */
+         currExisting = max;
+      }
+
+      char buffer[8];
+      ssize_t res = xReadfileat(cpuDirFd, "online", buffer, sizeof(buffer));
+      /* If the file "online" does not exist or on failure count as active */
+      if (res < 1 || buffer[0] != '0') {
+         active++;
+         this->cpuData[id + 1].online = true;
+      } else {
+         this->cpuData[id + 1].online = false;
+      }
+
+      Compat_openatArgClose(cpuDirFd);
+   }
+
+   closedir(dir);
+
+   // return if no CPU is found
+   if (existing < 1)
+      return;
+
+   if (Running_containerized) {
+      /* LXC munges /proc/cpuinfo but not the /sys/devices/system/cpu/ files,
+       * so limit the visible CPUs to what the guest has been configured to see: */
+      currExisting = active = scanAvailableCPUsFromCPUinfo(this);
+   }
+
+#ifdef HAVE_SENSORS_SENSORS_H
+   /* When started with offline CPUs, libsensors does not monitor those,
+    * even when they become online. */
+   if (super->existingCPUs != 0 && (active > super->activeCPUs || currExisting > super->existingCPUs))
+      LibSensors_reload();
+#endif
+
+   super->activeCPUs = active;
+   assert(Running_containerized || (existing == currExisting));
+   super->existingCPUs = currExisting;
+}
+
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* dynamicMeters, Hashtable* dynamicColumns, Hashtable* pidMatchList, uid_t userId) {
+   LinuxProcessList* this = xCalloc(1, sizeof(LinuxProcessList));
+   ProcessList* pl = &(this->super);
+
+   ProcessList_init(pl, Class(LinuxProcess), usersTable, dynamicMeters, dynamicColumns, pidMatchList, userId);
+   LinuxProcessList_initTtyDrivers(this);
+
+   // Initialize page size
+   pageSize = sysconf(_SC_PAGESIZE);
+   if (pageSize == -1)
+      CRT_fatalError("Cannot get pagesize by sysconf(_SC_PAGESIZE)");
+   pageSizeKB = pageSize / ONE_K;
+
+   // Initialize clock ticks
+   jiffy = sysconf(_SC_CLK_TCK);
+   if (jiffy == -1)
+      CRT_fatalError("Cannot get clock ticks by sysconf(_SC_CLK_TCK)");
+
+   // Test /proc/PID/smaps_rollup availability (faster to parse, Linux 4.14+)
+   this->haveSmapsRollup = (access(PROCDIR "/self/smaps_rollup", R_OK) == 0);
+
+   // Read btime (the kernel boot time, as number of seconds since the epoch)
+   FILE* statfile = fopen(PROCSTATFILE, "r");
+   if (statfile == NULL)
+      CRT_fatalError("Cannot open " PROCSTATFILE);
+   while (true) {
+      char buffer[PROC_LINE_LENGTH + 1];
+      if (fgets(buffer, sizeof(buffer), statfile) == NULL)
+         break;
+      if (String_startsWith(buffer, "btime ") == false)
+         continue;
+      if (sscanf(buffer, "btime %lld\n", &btime) == 1)
+         break;
+      CRT_fatalError("Failed to parse btime from " PROCSTATFILE);
+   }
+
+   fclose(statfile);
+
+   if (btime == -1)
+      CRT_fatalError("No btime in " PROCSTATFILE);
+
+   // Initialize CPU count
+   LinuxProcessList_updateCPUcount(pl);
+
+   return pl;
+}
+
+void ProcessList_delete(ProcessList* pl) {
+   LinuxProcessList* this = (LinuxProcessList*) pl;
+   ProcessList_done(pl);
+   free(this->cpuData);
+   if (this->ttyDrivers) {
+      for (int i = 0; this->ttyDrivers[i].path; i++) {
+         free(this->ttyDrivers[i].path);
+      }
+      free(this->ttyDrivers);
+   }
+   #ifdef HAVE_DELAYACCT
+   if (this->netlink_socket) {
+      nl_close(this->netlink_socket);
+      nl_socket_free(this->netlink_socket);
+   }
+   #endif
+   free(this);
+}
+
+static inline unsigned long long LinuxProcessList_adjustTime(unsigned long long t) {
+   return t * 100 / jiffy;
+}
+
+/* Taken from: https://github.com/torvalds/linux/blob/64570fbc14f8d7cb3fe3995f20e26bc25ce4b2cc/fs/proc/array.c#L120 */
+static inline ProcessState LinuxProcessList_getProcessState(char state) {
+   switch (state) {
+      case 'S': return SLEEPING;
+      case 'X': return DEFUNCT;
+      case 'Z': return ZOMBIE;
+      case 't': return TRACED;
+      case 'T': return STOPPED;
+      case 'D': return UNINTERRUPTIBLE_WAIT;
+      case 'R': return RUNNING;
+      case 'P': return BLOCKED;
+      case 'I': return IDLE;
+      default: return UNKNOWN;
+   }
+}
+
+static bool LinuxProcessList_readStatFile(Process* process, openat_arg_t procFd, char* command, size_t commLen) {
+   LinuxProcess* lp = (LinuxProcess*) process;
+
+   char buf[MAX_READ + 1];
+   ssize_t r = xReadfileat(procFd, "stat", buf, sizeof(buf));
+   if (r < 0)
+      return false;
+
+   /* (1) pid   -  %d */
+   assert(process->pid == atoi(buf));
+   char* location = strchr(buf, ' ');
+   if (!location)
+      return false;
+
+   /* (2) comm  -  (%s) */
+   location += 2;
+   char* end = strrchr(location, ')');
+   if (!end)
+      return false;
+
+   String_safeStrncpy(command, location, MINIMUM((size_t)(end - location + 1), commLen));
+
+   location = end + 2;
+
+   /* (3) state  -  %c */
+   process->state = LinuxProcessList_getProcessState(location[0]);
+   location += 2;
+
+   /* (4) ppid  -  %d */
+   process->ppid = strtol(location, &location, 10);
+   location += 1;
+
+   /* (5) pgrp  -  %d */
+   process->pgrp = strtol(location, &location, 10);
+   location += 1;
+
+   /* (6) session  -  %d */
+   process->session = strtol(location, &location, 10);
+   location += 1;
+
+   /* (7) tty_nr  -  %d */
+   process->tty_nr = strtoul(location, &location, 10);
+   location += 1;
+
+   /* (8) tpgid  -  %d */
+   process->tpgid = strtol(location, &location, 10);
+   location += 1;
+
+   /* (9) flags  -  %u */
+   lp->flags = strtoul(location, &location, 10);
+   location += 1;
+
+   /* (10) minflt  -  %lu */
+   process->minflt = strtoull(location, &location, 10);
+   location += 1;
+
+   /* (11) cminflt  -  %lu */
+   lp->cminflt = strtoull(location, &location, 10);
+   location += 1;
+
+   /* (12) majflt  -  %lu */
+   process->majflt = strtoull(location, &location, 10);
+   location += 1;
+
+   /* (13) cmajflt  -  %lu */
+   lp->cmajflt = strtoull(location, &location, 10);
+   location += 1;
+
+   /* (14) utime  -  %lu */
+   lp->utime = LinuxProcessList_adjustTime(strtoull(location, &location, 10));
+   location += 1;
+
+   /* (15) stime  -  %lu */
+   lp->stime = LinuxProcessList_adjustTime(strtoull(location, &location, 10));
+   location += 1;
+
+   /* (16) cutime  -  %ld */
+   lp->cutime = LinuxProcessList_adjustTime(strtoull(location, &location, 10));
+   location += 1;
+
+   /* (17) cstime  -  %ld */
+   lp->cstime = LinuxProcessList_adjustTime(strtoull(location, &location, 10));
+   location += 1;
+
+   /* (18) priority  -  %ld */
+   process->priority = strtol(location, &location, 10);
+   location += 1;
+
+   /* (19) nice  -  %ld */
+   process->nice = strtol(location, &location, 10);
+   location += 1;
+
+   /* (20) num_threads  -  %ld */
+   process->nlwp = strtol(location, &location, 10);
+   location += 1;
+
+   /* Skip (21) itrealvalue  -  %ld */
+   location = strchr(location, ' ') + 1;
+
+   /* (22) starttime  -  %llu */
+   if (process->starttime_ctime == 0) {
+      process->starttime_ctime = btime + LinuxProcessList_adjustTime(strtoll(location, &location, 10)) / 100;
+   } else {
+      location = strchr(location, ' ');
+   }
+   location += 1;
+
+   /* Skip (23) - (38) */
+   for (int i = 0; i < 16; i++) {
+      location = strchr(location, ' ') + 1;
+   }
+
+   assert(location != NULL);
+
+   /* (39) processor  -  %d */
+   process->processor = strtol(location, &location, 10);
+
+   /* Ignore further fields */
+
+   process->time = lp->utime + lp->stime;
+
+   return true;
+}
+
+
+static bool LinuxProcessList_updateUser(ProcessList* processList, Process* process, openat_arg_t procFd) {
+   struct stat sstat;
+#ifdef HAVE_OPENAT
+   int statok = fstat(procFd, &sstat);
+#else
+   int statok = stat(procFd, &sstat);
+#endif
+   if (statok == -1)
+      return false;
+
+   if (process->st_uid != sstat.st_uid) {
+      process->st_uid = sstat.st_uid;
+      process->user = UsersTable_getRef(processList->usersTable, sstat.st_uid);
+   }
+
+   return true;
+}
+
+static void LinuxProcessList_readIoFile(LinuxProcess* process, openat_arg_t procFd, unsigned long long realtimeMs) {
+   char buffer[1024];
+   ssize_t r = xReadfileat(procFd, "io", buffer, sizeof(buffer));
+   if (r < 0) {
+      process->io_rate_read_bps = NAN;
+      process->io_rate_write_bps = NAN;
+      process->io_rchar = ULLONG_MAX;
+      process->io_wchar = ULLONG_MAX;
+      process->io_syscr = ULLONG_MAX;
+      process->io_syscw = ULLONG_MAX;
+      process->io_read_bytes = ULLONG_MAX;
+      process->io_write_bytes = ULLONG_MAX;
+      process->io_cancelled_write_bytes = ULLONG_MAX;
+      process->io_last_scan_time_ms = realtimeMs;
+      return;
+   }
+
+   unsigned long long last_read = process->io_read_bytes;
+   unsigned long long last_write = process->io_write_bytes;
+   unsigned long long time_delta = realtimeMs > process->io_last_scan_time_ms ? realtimeMs - process->io_last_scan_time_ms : 0;
+
+   char* buf = buffer;
+   const char* line;
+   while ((line = strsep(&buf, "\n")) != NULL) {
+      switch (line[0]) {
+      case 'r':
+         if (line[1] == 'c' && String_startsWith(line + 2, "har: ")) {
+            process->io_rchar = strtoull(line + 7, NULL, 10);
+         } else if (String_startsWith(line + 1, "ead_bytes: ")) {
+            process->io_read_bytes = strtoull(line + 12, NULL, 10);
+            process->io_rate_read_bps = time_delta ? (process->io_read_bytes - last_read) * /*ms to s*/1000. / time_delta : NAN;
+         }
+         break;
+      case 'w':
+         if (line[1] == 'c' && String_startsWith(line + 2, "har: ")) {
+            process->io_wchar = strtoull(line + 7, NULL, 10);
+         } else if (String_startsWith(line + 1, "rite_bytes: ")) {
+            process->io_write_bytes = strtoull(line + 13, NULL, 10);
+            process->io_rate_write_bps = time_delta ? (process->io_write_bytes - last_write) * /*ms to s*/1000. / time_delta : NAN;
+         }
+         break;
+      case 's':
+         if (line[4] == 'r' && String_startsWith(line + 1, "yscr: ")) {
+            process->io_syscr = strtoull(line + 7, NULL, 10);
+         } else if (String_startsWith(line + 1, "yscw: ")) {
+            process->io_syscw = strtoull(line + 7, NULL, 10);
+         }
+         break;
+      case 'c':
+         if (String_startsWith(line + 1, "ancelled_write_bytes: ")) {
+            process->io_cancelled_write_bytes = strtoull(line + 23, NULL, 10);
+         }
+      }
+   }
+
+   process->io_last_scan_time_ms = realtimeMs;
+}
+
+typedef struct LibraryData_ {
+   uint64_t size;
+   bool exec;
+} LibraryData;
+
+static inline uint64_t fast_strtoull_dec(char** str, int maxlen) {
+   register uint64_t result = 0;
+
+   if (!maxlen)
+      --maxlen;
+
+   while (maxlen-- && **str >= '0' && **str <= '9') {
+      result *= 10;
+      result += **str - '0';
+      (*str)++;
+   }
+
+   return result;
+}
+
+static inline uint64_t fast_strtoull_hex(char** str, int maxlen) {
+   register uint64_t result = 0;
+   register int nibble, letter;
+   const long valid_mask = 0x03FF007E;
+
+   if (!maxlen)
+      --maxlen;
+
+   while (maxlen--) {
+      nibble = (unsigned char)**str;
+      if (!(valid_mask & (1 << (nibble & 0x1F))))
+         break;
+      if ((nibble < '0') || (nibble & ~0x20) > 'F')
+         break;
+      letter = (nibble & 0x40) ? 'A' - '9' - 1 : 0;
+      nibble &=~0x20; // to upper
+      nibble ^= 0x10; // switch letters and digits
+      nibble -= letter;
+      nibble &= 0x0f;
+      result <<= 4;
+      result += (uint64_t)nibble;
+      (*str)++;
+   }
+
+   return result;
+}
+
+static void LinuxProcessList_calcLibSize_helper(ATTR_UNUSED ht_key_t key, void* value, void* data) {
+   if (!data)
+      return;
+
+   if (!value)
+      return;
+
+   const LibraryData* v = (const LibraryData*)value;
+   uint64_t* d = (uint64_t*)data;
+   if (!v->exec)
+      return;
+
+   *d += v->size;
+}
+
+static void LinuxProcessList_readMaps(LinuxProcess* process, openat_arg_t procFd, bool calcSize, bool checkDeletedLib) {
+   Process* proc = (Process*)process;
+
+   proc->usesDeletedLib = false;
+
+   FILE* mapsfile = fopenat(procFd, "maps", "r");
+   if (!mapsfile)
+      return;
+
+   Hashtable* ht = NULL;
+   if (calcSize)
+      ht = Hashtable_new(64, true);
+
+   char buffer[1024];
+   while (fgets(buffer, sizeof(buffer), mapsfile)) {
+      uint64_t map_start;
+      uint64_t map_end;
+      bool map_execute;
+      unsigned int map_devmaj;
+      unsigned int map_devmin;
+      uint64_t map_inode;
+
+      // Short circuit test: Look for a slash
+      if (!strchr(buffer, '/'))
+         continue;
+
+      // Parse format: "%Lx-%Lx %4s %x %2x:%2x %Ld"
+      char* readptr = buffer;
+
+      map_start = fast_strtoull_hex(&readptr, 16);
+      if ('-' != *readptr++)
+         continue;
+
+      map_end = fast_strtoull_hex(&readptr, 16);
+      if (' ' != *readptr++)
+         continue;
+
+      map_execute = (readptr[2] == 'x');
+      readptr += 4;
+      if (' ' != *readptr++)
+         continue;
+
+      while (*readptr > ' ')
+         readptr++; // Skip parsing this hex value
+      if (' ' != *readptr++)
+         continue;
+
+      map_devmaj = fast_strtoull_hex(&readptr, 4);
+      if (':' != *readptr++)
+         continue;
+
+      map_devmin = fast_strtoull_hex(&readptr, 4);
+      if (' ' != *readptr++)
+         continue;
+
+      //Minor shortcut: Once we know there's no file for this region, we skip
+      if (!map_devmaj && !map_devmin)
+         continue;
+
+      map_inode = fast_strtoull_dec(&readptr, 20);
+      if (!map_inode)
+         continue;
+
+      if (calcSize) {
+         LibraryData* libdata = Hashtable_get(ht, map_inode);
+         if (!libdata) {
+            libdata = xCalloc(1, sizeof(LibraryData));
+            Hashtable_put(ht, map_inode, libdata);
+         }
+
+         libdata->size += map_end - map_start;
+         libdata->exec |= map_execute;
+      }
+
+      if (checkDeletedLib && map_execute && !proc->usesDeletedLib) {
+         while (*readptr == ' ')
+            readptr++;
+
+         if (*readptr != '/')
+            continue;
+
+         if (String_startsWith(readptr, "/memfd:"))
+            continue;
+
+         /* Virtualbox maps /dev/zero for memory allocation. That results in
+          * false positive, so ignore. */
+         if (String_eq(readptr, "/dev/zero (deleted)\n"))
+            continue;
+
+         if (strstr(readptr, " (deleted)\n")) {
+            proc->usesDeletedLib = true;
+            if (!calcSize)
+               break;
+         }
+      }
+   }
+
+   fclose(mapsfile);
+
+   if (calcSize) {
+      uint64_t total_size = 0;
+      Hashtable_foreach(ht, LinuxProcessList_calcLibSize_helper, &total_size);
+
+      Hashtable_delete(ht);
+
+      process->m_lrs = total_size / pageSize;
+   }
+}
+
+static bool LinuxProcessList_readStatmFile(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* statmfile = fopenat(procFd, "statm", "r");
+   if (!statmfile)
+      return false;
+
+   long int dummy, dummy2;
+
+   int r = fscanf(statmfile, "%ld %ld %ld %ld %ld %ld %ld",
+                  &process->super.m_virt,
+                  &process->super.m_resident,
+                  &process->m_share,
+                  &process->m_trs,
+                  &dummy, /* unused since Linux 2.6; always 0 */
+                  &process->m_drs,
+                  &dummy2); /* unused since Linux 2.6; always 0 */
+   fclose(statmfile);
+
+   if (r == 7) {
+      process->super.m_virt *= pageSizeKB;
+      process->super.m_resident *= pageSizeKB;
+   }
+
+   return r == 7;
+}
+
+static bool LinuxProcessList_checkPidNamespace(Process* process, openat_arg_t procFd) {
+   FILE* statusfile = fopenat(procFd, "status", "r");
+   if (!statusfile)
+      return false;
+
+   while (true) {
+      char buffer[PROC_LINE_LENGTH + 1];
+      if (fgets(buffer, sizeof(buffer), statusfile) == NULL)
+         break;
+
+      if (!String_startsWith(buffer, "NSpid:"))
+         continue;
+
+      char* ptr = buffer;
+      int pid_ns_count = 0;
+      while (*ptr && *ptr != '\n' && !isdigit(*ptr))
+         ++ptr;
+
+      while (*ptr && *ptr != '\n') {
+         if (isdigit(*ptr))
+            pid_ns_count++;
+         while (isdigit(*ptr))
+            ++ptr;
+         while (*ptr && *ptr != '\n' && !isdigit(*ptr))
+            ++ptr;
+      }
+
+      if (pid_ns_count > 1)
+         process->isRunningInContainer = true;
+
+      break;
+   }
+
+   fclose(statusfile);
+   return true;
+}
+
+static bool LinuxProcessList_readSmapsFile(LinuxProcess* process, openat_arg_t procFd, bool haveSmapsRollup) {
+   //http://elixir.free-electrons.com/linux/v4.10/source/fs/proc/task_mmu.c#L719
+   //kernel will return data in chunks of size PAGE_SIZE or less.
+   FILE* f = fopenat(procFd, haveSmapsRollup ? "smaps_rollup" : "smaps", "r");
+   if (!f)
+      return false;
+
+   process->m_pss   = 0;
+   process->m_swap  = 0;
+   process->m_psswp = 0;
+
+   char buffer[256];
+   while (fgets(buffer, sizeof(buffer), f)) {
+      if (!strchr(buffer, '\n')) {
+         // Partial line, skip to end of this line
+         while (fgets(buffer, sizeof(buffer), f)) {
+            if (strchr(buffer, '\n')) {
+               break;
+            }
+         }
+         continue;
+      }
+
+      if (String_startsWith(buffer, "Pss:")) {
+         process->m_pss += strtol(buffer + 4, NULL, 10);
+      } else if (String_startsWith(buffer, "Swap:")) {
+         process->m_swap += strtol(buffer + 5, NULL, 10);
+      } else if (String_startsWith(buffer, "SwapPss:")) {
+         process->m_psswp += strtol(buffer + 8, NULL, 10);
+      }
+   }
+
+   fclose(f);
+   return true;
+}
+
+#ifdef HAVE_OPENVZ
+
+static void LinuxProcessList_readOpenVZData(LinuxProcess* process, openat_arg_t procFd) {
+   if (access(PROCDIR "/vz", R_OK) != 0) {
+      free(process->ctid);
+      process->ctid = NULL;
+      process->vpid = process->super.pid;
+      return;
+   }
+
+   FILE* file = fopenat(procFd, "status", "r");
+   if (!file) {
+      free(process->ctid);
+      process->ctid = NULL;
+      process->vpid = process->super.pid;
+      return;
+   }
+
+   bool foundEnvID = false;
+   bool foundVPid = false;
+   char linebuf[256];
+   while (fgets(linebuf, sizeof(linebuf), file) != NULL) {
+      if (strchr(linebuf, '\n') == NULL) {
+         // Partial line, skip to end of this line
+         while (fgets(linebuf, sizeof(linebuf), file) != NULL) {
+            if (strchr(linebuf, '\n') != NULL) {
+               break;
+            }
+         }
+         continue;
+      }
+
+      char* name_value_sep = strchr(linebuf, ':');
+      if (name_value_sep == NULL) {
+         continue;
+      }
+
+      int field;
+      if (0 == strncasecmp(linebuf, "envID", name_value_sep - linebuf)) {
+         field = 1;
+      } else if (0 == strncasecmp(linebuf, "VPid", name_value_sep - linebuf)) {
+         field = 2;
+      } else {
+         continue;
+      }
+
+      do {
+         name_value_sep++;
+      } while (*name_value_sep != '\0' && *name_value_sep <= 32);
+
+      char* value_end = name_value_sep;
+
+      while (*value_end > 32) {
+         value_end++;
+      }
+
+      if (name_value_sep == value_end) {
+         continue;
+      }
+
+      *value_end = '\0';
+
+      switch (field) {
+      case 1:
+         foundEnvID = true;
+         if (!String_eq(name_value_sep, process->ctid ? process->ctid : ""))
+            free_and_xStrdup(&process->ctid, name_value_sep);
+         break;
+      case 2:
+         foundVPid = true;
+         process->vpid = strtoul(name_value_sep, NULL, 0);
+         break;
+      default:
+         //Sanity Check: Should never reach here, or the implementation is missing something!
+         assert(false && "OpenVZ handling: Unimplemented case for field handling reached.");
+      }
+   }
+
+   fclose(file);
+
+   if (!foundEnvID) {
+      free(process->ctid);
+      process->ctid = NULL;
+   }
+
+   if (!foundVPid) {
+      process->vpid = process->super.pid;
+   }
+}
+
+#endif
+
+static bool isContainerOrVMSlice(char* cgroup) {
+   if (String_startsWith(cgroup, "/user") || String_startsWith(cgroup, "/system"))
+      return false;
+
+   return true;
+}
+
+static void LinuxProcessList_readCGroupFile(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* file = fopenat(procFd, "cgroup", "r");
+   if (!file) {
+      if (process->cgroup) {
+         free(process->cgroup);
+         process->cgroup = NULL;
+      }
+      if (process->cgroup_short) {
+         free(process->cgroup_short);
+         process->cgroup_short = NULL;
+      }
+      return;
+   }
+   char output[PROC_LINE_LENGTH + 1];
+   output[0] = '\0';
+   char* at = output;
+   int left = PROC_LINE_LENGTH;
+   while (!feof(file) && left > 0) {
+      char buffer[PROC_LINE_LENGTH + 1];
+      const char* ok = fgets(buffer, PROC_LINE_LENGTH, file);
+      if (!ok)
+         break;
+
+      char* group = buffer;
+      for (size_t i = 0; i < 2; i++) {
+         group = strchrnul(group, ':');
+         if (!*group)
+            break;
+         group++;
+      }
+
+      char* eol = strchrnul(group, '\n');
+      *eol = '\0';
+
+      if (at != output) {
+         *at = ';';
+         at++;
+         left--;
+      }
+      int wrote = snprintf(at, left, "%s", group);
+      left -= wrote;
+   }
+   fclose(file);
+
+   bool changed = !process->cgroup || !String_eq(process->cgroup, output);
+
+   Process_updateFieldWidth(CGROUP, strlen(output));
+   free_and_xStrdup(&process->cgroup, output);
+
+   if (!changed) {
+      if (process->cgroup_short) {
+         Process_updateFieldWidth(CCGROUP, strlen(process->cgroup_short));
+      } else {
+         //CCGROUP is alias to normal CGROUP if shortening fails
+         Process_updateFieldWidth(CCGROUP, strlen(process->cgroup));
+      }
+      return;
+   }
+
+   char* cgroup_short = CGroup_filterName(process->cgroup);
+   if (cgroup_short) {
+      Process_updateFieldWidth(CCGROUP, strlen(cgroup_short));
+      free_and_xStrdup(&process->cgroup_short, cgroup_short);
+      free(cgroup_short);
+   } else {
+      //CCGROUP is alias to normal CGROUP if shortening fails
+      Process_updateFieldWidth(CCGROUP, strlen(process->cgroup));
+      free(process->cgroup_short);
+      process->cgroup_short = NULL;
+   }
+}
+
+#ifdef HAVE_VSERVER
+
+static void LinuxProcessList_readVServerData(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* file = fopenat(procFd, "status", "r");
+   if (!file)
+      return;
+
+   char buffer[PROC_LINE_LENGTH + 1];
+   process->vxid = 0;
+   while (fgets(buffer, PROC_LINE_LENGTH, file)) {
+      if (String_startsWith(buffer, "VxID:")) {
+         int vxid;
+         int ok = sscanf(buffer, "VxID:\t%32d", &vxid);
+         if (ok >= 1) {
+            process->vxid = vxid;
+         }
+      }
+      #if defined HAVE_ANCIENT_VSERVER
+      else if (String_startsWith(buffer, "s_context:")) {
+         int vxid;
+         int ok = sscanf(buffer, "s_context:\t%32d", &vxid);
+         if (ok >= 1) {
+            process->vxid = vxid;
+         }
+      }
+      #endif
+   }
+   fclose(file);
+}
+
+#endif
+
+static void LinuxProcessList_readOomData(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* file = fopenat(procFd, "oom_score", "r");
+   if (!file)
+      return;
+
+   char buffer[PROC_LINE_LENGTH + 1];
+   if (fgets(buffer, PROC_LINE_LENGTH, file)) {
+      unsigned int oom;
+      int ok = sscanf(buffer, "%u", &oom);
+      if (ok >= 1) {
+         process->oom = oom;
+      }
+   }
+   fclose(file);
+}
+
+static void LinuxProcessList_readAutogroup(LinuxProcess* process, openat_arg_t procFd) {
+   process->autogroup_id = -1;
+
+   char autogroup[64]; // space for two numeric values and fixed length strings
+   ssize_t amtRead = xReadfileat(procFd, "autogroup", autogroup, sizeof(autogroup));
+   if (amtRead < 0)
+      return;
+
+   long int identity;
+   int nice;
+   int ok = sscanf(autogroup, "/autogroup-%ld nice %d", &identity, &nice);
+   if (ok == 2) {
+      process->autogroup_id = identity;
+      process->autogroup_nice = nice;
+   }
+}
+
+static void LinuxProcessList_readCtxtData(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* file = fopenat(procFd, "status", "r");
+   if (!file)
+      return;
+
+   char buffer[PROC_LINE_LENGTH + 1];
+   unsigned long ctxt = 0;
+   while (fgets(buffer, PROC_LINE_LENGTH, file)) {
+      if (String_startsWith(buffer, "voluntary_ctxt_switches:")) {
+         unsigned long vctxt;
+         int ok = sscanf(buffer, "voluntary_ctxt_switches:\t%lu", &vctxt);
+         if (ok >= 1) {
+            ctxt += vctxt;
+         }
+      } else if (String_startsWith(buffer, "nonvoluntary_ctxt_switches:")) {
+         unsigned long nvctxt;
+         int ok = sscanf(buffer, "nonvoluntary_ctxt_switches:\t%lu", &nvctxt);
+         if (ok >= 1) {
+            ctxt += nvctxt;
+         }
+      }
+   }
+   fclose(file);
+   process->ctxt_diff = (ctxt > process->ctxt_total) ? (ctxt - process->ctxt_total) : 0;
+   process->ctxt_total = ctxt;
+}
+
+static void LinuxProcessList_readSecattrData(LinuxProcess* process, openat_arg_t procFd) {
+   FILE* file = fopenat(procFd, "attr/current", "r");
+   if (!file) {
+      free(process->secattr);
+      process->secattr = NULL;
+      return;
+   }
+
+   char buffer[PROC_LINE_LENGTH + 1];
+   const char* res = fgets(buffer, sizeof(buffer), file);
+   fclose(file);
+   if (!res) {
+      free(process->secattr);
+      process->secattr = NULL;
+      return;
+   }
+   char* newline = strchr(buffer, '\n');
+   if (newline) {
+      *newline = '\0';
+   }
+
+   Process_updateFieldWidth(SECATTR, strlen(buffer));
+
+   if (process->secattr && String_eq(process->secattr, buffer)) {
+      return;
+   }
+   free_and_xStrdup(&process->secattr, buffer);
+}
+
+static void LinuxProcessList_readCwd(LinuxProcess* process, openat_arg_t procFd) {
+   char pathBuffer[PATH_MAX + 1] = {0};
+
+#if defined(HAVE_READLINKAT) && defined(HAVE_OPENAT)
+   ssize_t r = readlinkat(procFd, "cwd", pathBuffer, sizeof(pathBuffer) - 1);
+#else
+   ssize_t r = Compat_readlink(procFd, "cwd", pathBuffer, sizeof(pathBuffer) - 1);
+#endif
+
+   if (r < 0) {
+      free(process->super.procCwd);
+      process->super.procCwd = NULL;
+      return;
+   }
+
+   pathBuffer[r] = '\0';
+
+   if (process->super.procCwd && String_eq(process->super.procCwd, pathBuffer))
+      return;
+
+   free_and_xStrdup(&process->super.procCwd, pathBuffer);
+}
+
+#ifdef HAVE_DELAYACCT
+
+static int handleNetlinkMsg(struct nl_msg* nlmsg, void* linuxProcess) {
+   struct nlmsghdr* nlhdr;
+   struct nlattr* nlattrs[TASKSTATS_TYPE_MAX + 1];
+   const struct nlattr* nlattr;
+   struct taskstats stats;
+   int rem;
+   LinuxProcess* lp = (LinuxProcess*) linuxProcess;
+
+   nlhdr = nlmsg_hdr(nlmsg);
+
+   if (genlmsg_parse(nlhdr, 0, nlattrs, TASKSTATS_TYPE_MAX, NULL) < 0) {
+      return NL_SKIP;
+   }
+
+   if ((nlattr = nlattrs[TASKSTATS_TYPE_AGGR_PID]) || (nlattr = nlattrs[TASKSTATS_TYPE_NULL])) {
+      memcpy(&stats, nla_data(nla_next(nla_data(nlattr), &rem)), sizeof(stats));
+      assert(lp->super.pid == (pid_t)stats.ac_pid);
+
+      unsigned long long int timeDelta = stats.ac_etime * 1000 - lp->delay_read_time;
+      #define BOUNDS(x) (isnan(x) ? 0.0 : ((x) > 100) ? 100.0 : (x))
+      #define DELTAPERC(x,y) BOUNDS((float) ((x) - (y)) / timeDelta * 100)
+      lp->cpu_delay_percent = DELTAPERC(stats.cpu_delay_total, lp->cpu_delay_total);
+      lp->blkio_delay_percent = DELTAPERC(stats.blkio_delay_total, lp->blkio_delay_total);
+      lp->swapin_delay_percent = DELTAPERC(stats.swapin_delay_total, lp->swapin_delay_total);
+      #undef DELTAPERC
+      #undef BOUNDS
+
+      lp->swapin_delay_total = stats.swapin_delay_total;
+      lp->blkio_delay_total = stats.blkio_delay_total;
+      lp->cpu_delay_total = stats.cpu_delay_total;
+      lp->delay_read_time = stats.ac_etime * 1000;
+   }
+   return NL_OK;
+}
+
+static void LinuxProcessList_readDelayAcctData(LinuxProcessList* this, LinuxProcess* process) {
+   struct nl_msg* msg;
+
+   if (!this->netlink_socket) {
+      LinuxProcessList_initNetlinkSocket(this);
+      if (!this->netlink_socket) {
+         goto delayacct_failure;
+      }
+   }
+
+   if (nl_socket_modify_cb(this->netlink_socket, NL_CB_VALID, NL_CB_CUSTOM, handleNetlinkMsg, process) < 0) {
+      goto delayacct_failure;
+   }
+
+   if (! (msg = nlmsg_alloc())) {
+      goto delayacct_failure;
+   }
+
+   if (! genlmsg_put(msg, NL_AUTO_PID, NL_AUTO_SEQ, this->netlink_family, 0, NLM_F_REQUEST, TASKSTATS_CMD_GET, TASKSTATS_VERSION)) {
+      nlmsg_free(msg);
+   }
+
+   if (nla_put_u32(msg, TASKSTATS_CMD_ATTR_PID, process->super.pid) < 0) {
+      nlmsg_free(msg);
+   }
+
+   if (nl_send_sync(this->netlink_socket, msg) < 0) {
+      goto delayacct_failure;
+   }
+
+   if (nl_recvmsgs_default(this->netlink_socket) < 0) {
+      goto delayacct_failure;
+   }
+
+   return;
+
+delayacct_failure:
+   process->swapin_delay_percent = NAN;
+   process->blkio_delay_percent = NAN;
+   process->cpu_delay_percent = NAN;
+}
+
+#endif
+
+static bool LinuxProcessList_readCmdlineFile(Process* process, openat_arg_t procFd) {
+   char command[4096 + 1]; // max cmdline length on Linux
+   ssize_t amtRead = xReadfileat(procFd, "cmdline", command, sizeof(command));
+   if (amtRead <= 0)
+      return false;
+
+   int tokenEnd = 0;
+   int tokenStart = 0;
+   int lastChar = 0;
+   bool argSepNUL = false;
+   bool argSepSpace = false;
+
+   for (int i = 0; i < amtRead; i++) {
+      /* newline used as delimiter - when forming the mergedCommand, newline is
+       * converted to space by Process_makeCommandStr */
+      if (command[i] == '\0') {
+         command[i] = '\n';
+      } else {
+         /* Record some information for the argument parsing heuristic below. */
+         if (tokenEnd)
+            argSepNUL = true;
+         if (command[i] <= ' ')
+            argSepSpace = true;
+      }
+
+      if (command[i] == '\n') {
+         if (tokenEnd == 0) {
+            tokenEnd = i;
+         }
+      } else {
+         /* htop considers the next character after the last / that is before
+          * basenameOffset, as the start of the basename in cmdline - see
+          * Process_writeCommand */
+         if (!tokenEnd && command[i] == '/') {
+            tokenStart = i + 1;
+         }
+         lastChar = i;
+      }
+   }
+
+   command[lastChar + 1] = '\0';
+
+   if (!argSepNUL && argSepSpace) {
+      /* Argument parsing heuristic.
+       *
+       * This heuristic is used for processes that rewrite their command line.
+       * Normally the command line is split by using NUL bytes between each argument.
+       * But some programs like chrome flatten this using spaces.
+       *
+       * This heuristic tries its best to undo this loss of information.
+       * To achieve this, we treat every character <= 32 as argument separators
+       * (i.e. all of ASCII control sequences and space).
+       * We then search for the basename of the cmdline in the first argument we found that way.
+       * As path names may contain we try to cross-validate if the path we got that way exists.
+       */
+
+      tokenStart = tokenEnd = 0;
+
+      // From initial scan we know there's at least one space.
+      // Check if that's part of a filename for an existing file.
+      if (Compat_faccessat(AT_FDCWD, command, F_OK, AT_SYMLINK_NOFOLLOW) != 0) {
+         // If we reach here the path does not exist.
+         // Thus begin searching for the part of it that actually is.
+
+         int tokenArg0Start = 0;
+
+         for (int i = 0; i <= lastChar; i++) {
+            /* Any ASCII control or space used as delimiter */
+            char tmpCommandChar = command[i];
+
+            if (command[i] <= ' ') {
+               if (!tokenEnd) {
+                  command[i] = '\0';
+
+                  bool found = Compat_faccessat(AT_FDCWD, command, F_OK, AT_SYMLINK_NOFOLLOW) == 0;
+
+                  // Restore if this wasn't it
+                  command[i] = found ? '\n' : tmpCommandChar;
+
+                  if (found)
+                     tokenEnd = i;
+                  if (!tokenArg0Start)
+                     tokenArg0Start = tokenStart;
+               } else {
+                  // Split on every further separator, regardless of path correctness
+                  command[i] = '\n';
+               }
+            } else if (!tokenEnd) {
+               if (command[i] == '/' || (command[i] == '\\' && (!tokenStart || command[tokenStart - 1] == '\\'))) {
+                  tokenStart = i + 1;
+               } else if (command[i] == ':' && (command[i + 1] != '/' && command[i + 1] != '\\')) {
+                  tokenEnd = i;
+               }
+            }
+         }
+
+         if (!tokenEnd) {
+            tokenStart = tokenArg0Start;
+
+            // No token delimiter found, forcibly split
+            for (int i = 0; i <= lastChar; i++) {
+               if (command[i] <= ' ') {
+                  command[i] = '\n';
+                  if (!tokenEnd) {
+                     tokenEnd = i;
+                  }
+               }
+            }
+         }
+      }
+
+      /* Some command lines are hard to parse, like
+       *   file.so [kdeinit5] file local:/run/user/1000/klauncherdqbouY.1.slave-socket local:/run/user/1000/kded5TwsDAx.1.slave-socket
+       * Reset if start is behind end.
+       */
+      if (tokenStart >= tokenEnd)
+         tokenStart = tokenEnd = 0;
+   }
+
+   if (tokenEnd == 0) {
+      tokenEnd = lastChar + 1;
+   }
+
+   Process_updateCmdline(process, command, tokenStart, tokenEnd);
+
+   /* /proc/[pid]/comm could change, so should be updated */
+   if ((amtRead = xReadfileat(procFd, "comm", command, sizeof(command))) > 0) {
+      command[amtRead - 1] = '\0';
+      Process_updateComm(process, command);
+   } else {
+      Process_updateComm(process, NULL);
+   }
+
+   char filename[MAX_NAME + 1];
+
+   /* execve could change /proc/[pid]/exe, so procExe should be updated */
+#if defined(HAVE_READLINKAT) && defined(HAVE_OPENAT)
+   amtRead = readlinkat(procFd, "exe", filename, sizeof(filename) - 1);
+#else
+   amtRead = Compat_readlink(procFd, "exe", filename, sizeof(filename) - 1);
+#endif
+   if (amtRead > 0) {
+      filename[amtRead] = 0;
+      if (!process->procExe ||
+          (!process->procExeDeleted && !String_eq(filename, process->procExe)) ||
+          process->procExeDeleted) {
+
+         const char* deletedMarker = " (deleted)";
+         const size_t markerLen = strlen(deletedMarker);
+         const size_t filenameLen = strlen(filename);
+
+         if (filenameLen > markerLen) {
+            bool oldExeDeleted = process->procExeDeleted;
+
+            process->procExeDeleted = String_eq(filename + filenameLen - markerLen, deletedMarker);
+
+            if (process->procExeDeleted)
+               filename[filenameLen - markerLen] = '\0';
+
+            if (oldExeDeleted != process->procExeDeleted)
+               process->mergedCommand.lastUpdate = 0;
+         }
+
+         Process_updateExe(process, filename);
+      }
+   } else if (process->procExe) {
+      Process_updateExe(process, NULL);
+      process->procExeDeleted = false;
+   }
+
+   return true;
+}
+
+static char* LinuxProcessList_updateTtyDevice(TtyDriver* ttyDrivers, unsigned long int tty_nr) {
+   unsigned int maj = major(tty_nr);
+   unsigned int min = minor(tty_nr);
+
+   int i = -1;
+   for (;;) {
+      i++;
+      if ((!ttyDrivers[i].path) || maj < ttyDrivers[i].major) {
+         break;
+      }
+      if (maj > ttyDrivers[i].major) {
+         continue;
+      }
+      if (min < ttyDrivers[i].minorFrom) {
+         break;
+      }
+      if (min > ttyDrivers[i].minorTo) {
+         continue;
+      }
+      unsigned int idx = min - ttyDrivers[i].minorFrom;
+      struct stat sstat;
+      char* fullPath;
+      for (;;) {
+         xAsprintf(&fullPath, "%s/%d", ttyDrivers[i].path, idx);
+         int err = stat(fullPath, &sstat);
+         if (err == 0 && major(sstat.st_rdev) == maj && minor(sstat.st_rdev) == min) {
+            return fullPath;
+         }
+         free(fullPath);
+
+         xAsprintf(&fullPath, "%s%d", ttyDrivers[i].path, idx);
+         err = stat(fullPath, &sstat);
+         if (err == 0 && major(sstat.st_rdev) == maj && minor(sstat.st_rdev) == min) {
+            return fullPath;
+         }
+         free(fullPath);
+
+         if (idx == min) {
+            break;
+         }
+
+         idx = min;
+      }
+      int err = stat(ttyDrivers[i].path, &sstat);
+      if (err == 0 && tty_nr == sstat.st_rdev) {
+         return xStrdup(ttyDrivers[i].path);
+      }
+   }
+   char* out;
+   xAsprintf(&out, "/dev/%u:%u", maj, min);
+   return out;
+}
+
+static bool isOlderThan(const ProcessList* pl, const Process* proc, unsigned int seconds) {
+   assert(pl->realtimeMs > 0);
+
+   /* Starttime might not yet be parsed */
+   if (proc->starttime_ctime <= 0)
+      return false;
+
+   uint64_t realtime = pl->realtimeMs / 1000;
+
+   if (realtime < (uint64_t)proc->starttime_ctime)
+      return false;
+
+   return realtime - proc->starttime_ctime > seconds;
+}
+
+static bool LinuxProcessList_recurseProcTree(LinuxProcessList* this, openat_arg_t parentFd, const char* dirname, const Process* parent, double period) {
+   ProcessList* pl = (ProcessList*) this;
+   const struct dirent* entry;
+   const Settings* settings = pl->settings;
+   const ScreenSettings* ss = settings->ss;
+
+#ifdef HAVE_OPENAT
+   int dirFd = openat(parentFd, dirname, O_RDONLY | O_DIRECTORY | O_NOFOLLOW);
+   if (dirFd < 0)
+      return false;
+   DIR* dir = fdopendir(dirFd);
+#else
+   char dirFd[4096];
+   xSnprintf(dirFd, sizeof(dirFd), "%s/%s", parentFd, dirname);
+   DIR* dir = opendir(dirFd);
+#endif
+   if (!dir) {
+      Compat_openatArgClose(dirFd);
+      return false;
+   }
+
+   const unsigned int activeCPUs = pl->activeCPUs;
+   const bool hideKernelThreads = settings->hideKernelThreads;
+   const bool hideUserlandThreads = settings->hideUserlandThreads;
+   const bool hideRunningInContainer = settings->hideRunningInContainer;
+   while ((entry = readdir(dir)) != NULL) {
+      const char* name = entry->d_name;
+
+      // Ignore all non-directories
+      if (entry->d_type != DT_DIR && entry->d_type != DT_UNKNOWN) {
+         continue;
+      }
+
+      // The RedHat kernel hides threads with a dot.
+      // I believe this is non-standard.
+      if (name[0] == '.') {
+         name++;
+      }
+
+      // Just skip all non-number directories.
+      if (name[0] < '0' || name[0] > '9') {
+         continue;
+      }
+
+      // filename is a number: process directory
+      int pid;
+      {
+         char* endptr;
+         unsigned long parsedPid = strtoul(name, &endptr, 10);
+         if (parsedPid == 0 || parsedPid == ULONG_MAX || *endptr != '\0')
+            continue;
+         pid = parsedPid;
+      }
+
+      // Skip task directory of main thread
+      if (parent && pid == parent->pid)
+         continue;
+
+#ifdef HAVE_OPENAT
+      int procFd = openat(dirFd, entry->d_name, O_RDONLY | O_DIRECTORY | O_NOFOLLOW);
+      if (procFd < 0)
+         continue;
+#else
+      char procFd[4096];
+      xSnprintf(procFd, sizeof(procFd), "%s/%s", dirFd, entry->d_name);
+#endif
+
+      bool preExisting;
+      Process* proc = ProcessList_getProcess(pl, pid, &preExisting, LinuxProcess_new);
+      LinuxProcess* lp = (LinuxProcess*) proc;
+
+      proc->tgid = parent ? parent->pid : pid;
+      proc->isUserlandThread = proc->pid != proc->tgid;
+
+      LinuxProcessList_recurseProcTree(this, procFd, "task", proc, period);
+
+      if (ss->flags & PROCESS_FLAG_LINUX_CGROUP || hideRunningInContainer) {
+         LinuxProcessList_readCGroupFile(lp, procFd);
+         if (hideRunningInContainer && lp->cgroup && isContainerOrVMSlice(lp->cgroup)) {
+            if (!LinuxProcessList_checkPidNamespace(proc, procFd)) {
+               goto errorReadingProcess;
+            }
+         }
+      }
+
+      /*
+       * These conditions will not trigger on first occurrence, cause we need to
+       * add the process to the ProcessList and do all one time scans
+       * (e.g. parsing the cmdline to detect a kernel thread)
+       * But it will short-circuit subsequent scans.
+       */
+      if (preExisting && hideKernelThreads && Process_isKernelThread(proc)) {
+         proc->updated = true;
+         proc->show = false;
+         pl->kernelThreads++;
+         pl->totalTasks++;
+         Compat_openatArgClose(procFd);
+         continue;
+      }
+      if (preExisting && hideUserlandThreads && Process_isUserlandThread(proc)) {
+         proc->updated = true;
+         proc->show = false;
+         pl->userlandThreads++;
+         pl->totalTasks++;
+         Compat_openatArgClose(procFd);
+         continue;
+      }
+      if (preExisting && hideRunningInContainer && proc->isRunningInContainer) {
+         proc->updated = true;
+         proc->show = false;
+         Compat_openatArgClose(procFd);
+         continue;
+      }
+
+      if (ss->flags & PROCESS_FLAG_IO)
+         LinuxProcessList_readIoFile(lp, procFd, pl->realtimeMs);
+
+      if (!LinuxProcessList_readStatmFile(lp, procFd))
+         goto errorReadingProcess;
+
+      {
+         bool prev = proc->usesDeletedLib;
+
+         if (!proc->isKernelThread && !proc->isUserlandThread &&
+            ((ss->flags & PROCESS_FLAG_LINUX_LRS_FIX) || (settings->highlightDeletedExe && !proc->procExeDeleted && isOlderThan(pl, proc, 10)))) {
+
+            // Check if we really should recalculate the M_LRS value for this process
+            uint64_t passedTimeInMs = pl->realtimeMs - lp->last_mlrs_calctime;
+
+            uint64_t recheck = ((uint64_t)rand()) % 2048;
+
+            if (passedTimeInMs > recheck) {
+               lp->last_mlrs_calctime = pl->realtimeMs;
+               LinuxProcessList_readMaps(lp, procFd, ss->flags & PROCESS_FLAG_LINUX_LRS_FIX, settings->highlightDeletedExe);
+            }
+         } else {
+            /* Copy from process structure in threads and reset if setting got disabled */
+            proc->usesDeletedLib = (proc->isUserlandThread && parent) ? parent->usesDeletedLib : false;
+            lp->m_lrs = (proc->isUserlandThread && parent) ? ((const LinuxProcess*)parent)->m_lrs : 0;
+         }
+
+         if (prev != proc->usesDeletedLib)
+            proc->mergedCommand.lastUpdate = 0;
+      }
+
+      if ((ss->flags & PROCESS_FLAG_LINUX_SMAPS) && !Process_isKernelThread(proc)) {
+         if (!parent) {
+            // Read smaps file of each process only every second pass to improve performance
+            static int smaps_flag = 0;
+            if ((pid & 1) == smaps_flag) {
+               LinuxProcessList_readSmapsFile(lp, procFd, this->haveSmapsRollup);
+            }
+            if (pid == 1) {
+               smaps_flag = !smaps_flag;
+            }
+         } else {
+            lp->m_pss = ((const LinuxProcess*)parent)->m_pss;
+         }
+      }
+
+      char statCommand[MAX_NAME + 1];
+      unsigned long long int lasttimes = (lp->utime + lp->stime);
+      unsigned long int tty_nr = proc->tty_nr;
+      if (!LinuxProcessList_readStatFile(proc, procFd, statCommand, sizeof(statCommand)))
+         goto errorReadingProcess;
+
+      if (lp->flags & PF_KTHREAD) {
+         proc->isKernelThread = true;
+      }
+
+      if (tty_nr != proc->tty_nr && this->ttyDrivers) {
+         free(proc->tty_name);
+         proc->tty_name = LinuxProcessList_updateTtyDevice(this->ttyDrivers, proc->tty_nr);
+      }
+
+      if (ss->flags & PROCESS_FLAG_LINUX_IOPRIO) {
+         LinuxProcess_updateIOPriority(lp);
+      }
+
+      /* period might be 0 after system sleep */
+      float percent_cpu = (period < 1E-6) ? 0.0F : ((lp->utime + lp->stime - lasttimes) / period * 100.0);
+      proc->percent_cpu = CLAMP(percent_cpu, 0.0F, activeCPUs * 100.0F);
+      proc->percent_mem = proc->m_resident / (double)(pl->totalMem) * 100.0;
+      Process_updateCPUFieldWidths(proc->percent_cpu);
+
+      if (! LinuxProcessList_updateUser(pl, proc, procFd))
+         goto errorReadingProcess;
+
+      if (!preExisting) {
+
+         #ifdef HAVE_OPENVZ
+         if (ss->flags & PROCESS_FLAG_LINUX_OPENVZ) {
+            LinuxProcessList_readOpenVZData(lp, procFd);
+         }
+         #endif
+
+         #ifdef HAVE_VSERVER
+         if (ss->flags & PROCESS_FLAG_LINUX_VSERVER) {
+            LinuxProcessList_readVServerData(lp, procFd);
+         }
+         #endif
+
+         if (proc->isKernelThread) {
+            Process_updateCmdline(proc, NULL, 0, 0);
+         } else if (!LinuxProcessList_readCmdlineFile(proc, procFd)) {
+            Process_updateCmdline(proc, statCommand, 0, strlen(statCommand));
+         }
+
+         Process_fillStarttimeBuffer(proc);
+
+         ProcessList_add(pl, proc);
+      } else {
+         if (settings->updateProcessNames && proc->state != ZOMBIE) {
+            if (proc->isKernelThread) {
+               Process_updateCmdline(proc, NULL, 0, 0);
+            } else if (!LinuxProcessList_readCmdlineFile(proc, procFd)) {
+               Process_updateCmdline(proc, statCommand, 0, strlen(statCommand));
+            }
+         }
+      }
+
+      #ifdef HAVE_DELAYACCT
+      if (ss->flags & PROCESS_FLAG_LINUX_DELAYACCT) {
+         LinuxProcessList_readDelayAcctData(this, lp);
+      }
+      #endif
+
+      if (ss->flags & PROCESS_FLAG_LINUX_OOM) {
+         LinuxProcessList_readOomData(lp, procFd);
+      }
+
+      if (ss->flags & PROCESS_FLAG_LINUX_CTXT) {
+         LinuxProcessList_readCtxtData(lp, procFd);
+      }
+
+      if (ss->flags & PROCESS_FLAG_LINUX_SECATTR) {
+         LinuxProcessList_readSecattrData(lp, procFd);
+      }
+
+      if (ss->flags & PROCESS_FLAG_CWD) {
+         LinuxProcessList_readCwd(lp, procFd);
+      }
+
+      if ((ss->flags & PROCESS_FLAG_LINUX_AUTOGROUP) && this->haveAutogroup) {
+         LinuxProcessList_readAutogroup(lp, procFd);
+      }
+
+      if (!proc->cmdline && statCommand[0] &&
+          (proc->state == ZOMBIE || Process_isKernelThread(proc) || settings->showThreadNames)) {
+         Process_updateCmdline(proc, statCommand, 0, strlen(statCommand));
+      }
+
+      if (Process_isKernelThread(proc)) {
+         pl->kernelThreads++;
+      } else if (Process_isUserlandThread(proc)) {
+         pl->userlandThreads++;
+      }
+
+      /* Set at the end when we know if a new entry is a thread */
+      proc->show = ! ((hideKernelThreads && Process_isKernelThread(proc)) || (hideUserlandThreads && Process_isUserlandThread(proc)));
+
+      pl->totalTasks++;
+      /* runningTasks is set in LinuxProcessList_scanCPUTime() from /proc/stat */
+      proc->updated = true;
+      Compat_openatArgClose(procFd);
+      continue;
+
+      // Exception handler.
+
+errorReadingProcess:
+      {
+#ifdef HAVE_OPENAT
+         if (procFd >= 0)
+            close(procFd);
+#endif
+
+         if (preExisting) {
+            /*
+             * The only real reason for coming here (apart from Linux violating the /proc API)
+             * would be the process going away with its /proc files disappearing (!HAVE_OPENAT).
+             * However, we want to keep in the process list for now for the "highlight dying" mode.
+             */
+         } else {
+            /* A really short-lived process that we don't have full info about */
+            Process_delete((Object*)proc);
+         }
+      }
+   }
+   closedir(dir);
+   return true;
+}
+
+static inline void LinuxProcessList_scanMemoryInfo(ProcessList* this) {
+   memory_t availableMem = 0;
+   memory_t freeMem = 0;
+   memory_t totalMem = 0;
+   memory_t buffersMem = 0;
+   memory_t cachedMem = 0;
+   memory_t sharedMem = 0;
+   memory_t swapTotalMem = 0;
+   memory_t swapCacheMem = 0;
+   memory_t swapFreeMem = 0;
+   memory_t sreclaimableMem = 0;
+
+   FILE* file = fopen(PROCMEMINFOFILE, "r");
+   if (!file)
+      CRT_fatalError("Cannot open " PROCMEMINFOFILE);
+
+   char buffer[128];
+   while (fgets(buffer, sizeof(buffer), file)) {
+
+      #define tryRead(label, variable)                                       \
+         if (String_startsWith(buffer, label)) {                             \
+            memory_t parsed_;                                                \
+            if (sscanf(buffer + strlen(label), "%llu kB", &parsed_) == 1) {  \
+               (variable) = parsed_;                                         \
+            }                                                                \
+            break;                                                           \
+         } else (void) 0 /* Require a ";" after the macro use. */
+
+      switch (buffer[0]) {
+      case 'M':
+         tryRead("MemAvailable:", availableMem);
+         tryRead("MemFree:", freeMem);
+         tryRead("MemTotal:", totalMem);
+         break;
+      case 'B':
+         tryRead("Buffers:", buffersMem);
+         break;
+      case 'C':
+         tryRead("Cached:", cachedMem);
+         break;
+      case 'S':
+         switch (buffer[1]) {
+         case 'h':
+            tryRead("Shmem:", sharedMem);
+            break;
+         case 'w':
+            tryRead("SwapTotal:", swapTotalMem);
+            tryRead("SwapCached:", swapCacheMem);
+            tryRead("SwapFree:", swapFreeMem);
+            break;
+         case 'R':
+            tryRead("SReclaimable:", sreclaimableMem);
+            break;
+         }
+         break;
+      }
+
+      #undef tryRead
+   }
+
+   fclose(file);
+
+   /*
+    * Compute memory partition like procps(free)
+    *  https://gitlab.com/procps-ng/procps/-/blob/master/proc/sysinfo.c
+    *
+    * Adjustments:
+    *  - Shmem in part of Cached (see https://lore.kernel.org/patchwork/patch/648763/),
+    *    do not show twice by subtracting from Cached and do not subtract twice from used.
+    */
+   this->totalMem = totalMem;
+   this->cachedMem = cachedMem + sreclaimableMem - sharedMem;
+   this->sharedMem = sharedMem;
+   const memory_t usedDiff = freeMem + cachedMem + sreclaimableMem + buffersMem;
+   this->usedMem = (totalMem >= usedDiff) ? totalMem - usedDiff : totalMem - freeMem;
+   this->buffersMem = buffersMem;
+   this->availableMem = availableMem != 0 ? MINIMUM(availableMem, totalMem) : freeMem;
+   this->totalSwap = swapTotalMem;
+   this->usedSwap = swapTotalMem - swapFreeMem - swapCacheMem;
+   this->cachedSwap = swapCacheMem;
+}
+
+static void LinuxProcessList_scanHugePages(LinuxProcessList* this) {
+   this->totalHugePageMem = 0;
+   for (unsigned i = 0; i < HTOP_HUGEPAGE_COUNT; i++) {
+      this->usedHugePageMem[i] = MEMORY_MAX;
+   }
+
+   DIR* dir = opendir("/sys/kernel/mm/hugepages");
+   if (!dir)
+      return;
+
+   const struct dirent* entry;
+   while ((entry = readdir(dir)) != NULL) {
+      const char* name = entry->d_name;
+
+      /* Ignore all non-directories */
+      if (entry->d_type != DT_DIR && entry->d_type != DT_UNKNOWN)
+         continue;
+
+      if (!String_startsWith(name, "hugepages-"))
+         continue;
+
+      char* endptr;
+      unsigned long int hugePageSize = strtoul(name + strlen("hugepages-"), &endptr, 10);
+      if (!endptr || *endptr != 'k')
+         continue;
+
+      char content[64];
+      char hugePagePath[128];
+      ssize_t r;
+
+      xSnprintf(hugePagePath, sizeof(hugePagePath), "/sys/kernel/mm/hugepages/%s/nr_hugepages", name);
+      r = xReadfile(hugePagePath, content, sizeof(content));
+      if (r <= 0)
+         continue;
+
+      memory_t total = strtoull(content, NULL, 10);
+      if (total == 0)
+         continue;
+
+      xSnprintf(hugePagePath, sizeof(hugePagePath), "/sys/kernel/mm/hugepages/%s/free_hugepages", name);
+      r = xReadfile(hugePagePath, content, sizeof(content));
+      if (r <= 0)
+         continue;
+
+      memory_t free = strtoull(content, NULL, 10);
+
+      int shift = ffsl(hugePageSize) - 1 - (HTOP_HUGEPAGE_BASE_SHIFT - 10);
+      assert(shift >= 0 && shift < HTOP_HUGEPAGE_COUNT);
+
+      this->totalHugePageMem += total * hugePageSize;
+      this->usedHugePageMem[shift] = (total - free) * hugePageSize;
+   }
+
+   closedir(dir);
+}
+
+static inline void LinuxProcessList_scanZramInfo(LinuxProcessList* this) {
+   memory_t totalZram = 0;
+   memory_t usedZramComp = 0;
+   memory_t usedZramOrig = 0;
+
+   char mm_stat[34];
+   char disksize[34];
+
+   unsigned int i = 0;
+   for (;;) {
+      xSnprintf(mm_stat, sizeof(mm_stat), "/sys/block/zram%u/mm_stat", i);
+      xSnprintf(disksize, sizeof(disksize), "/sys/block/zram%u/disksize", i);
+      i++;
+      FILE* disksize_file = fopen(disksize, "r");
+      FILE* mm_stat_file = fopen(mm_stat, "r");
+      if (disksize_file == NULL || mm_stat_file == NULL) {
+         if (disksize_file) {
+            fclose(disksize_file);
+         }
+         if (mm_stat_file) {
+            fclose(mm_stat_file);
+         }
+         break;
+      }
+      memory_t size = 0;
+      memory_t orig_data_size = 0;
+      memory_t compr_data_size = 0;
+
+      if (!fscanf(disksize_file, "%llu\n", &size) ||
+          !fscanf(mm_stat_file, "    %llu       %llu", &orig_data_size, &compr_data_size)) {
+         fclose(disksize_file);
+         fclose(mm_stat_file);
+         break;
+      }
+
+      totalZram += size;
+      usedZramComp += compr_data_size;
+      usedZramOrig += orig_data_size;
+
+      fclose(disksize_file);
+      fclose(mm_stat_file);
+   }
+
+   this->zram.totalZram = totalZram / 1024;
+   this->zram.usedZramComp = usedZramComp / 1024;
+   this->zram.usedZramOrig = usedZramOrig / 1024;
+}
+
+static inline void LinuxProcessList_scanZfsArcstats(LinuxProcessList* lpl) {
+   memory_t dbufSize = 0;
+   memory_t dnodeSize = 0;
+   memory_t bonusSize = 0;
+
+   FILE* file = fopen(PROCARCSTATSFILE, "r");
+   if (file == NULL) {
+      lpl->zfs.enabled = 0;
+      return;
+   }
+   char buffer[128];
+   while (fgets(buffer, 128, file)) {
+      #define tryRead(label, variable)                                         \
+         if (String_startsWith(buffer, label)) {                               \
+            sscanf(buffer + strlen(label), " %*2u %32llu", variable);          \
+            break;                                                             \
+         } else (void) 0 /* Require a ";" after the macro use. */
+      #define tryReadFlag(label, variable, flag)                               \
+         if (String_startsWith(buffer, label)) {                               \
+            (flag) = sscanf(buffer + strlen(label), " %*2u %32llu", variable); \
+            break;                                                             \
+         } else (void) 0 /* Require a ";" after the macro use. */
+
+      switch (buffer[0]) {
+      case 'c':
+         tryRead("c_min", &lpl->zfs.min);
+         tryRead("c_max", &lpl->zfs.max);
+         tryReadFlag("compressed_size", &lpl->zfs.compressed, lpl->zfs.isCompressed);
+         break;
+      case 'u':
+         tryRead("uncompressed_size", &lpl->zfs.uncompressed);
+         break;
+      case 's':
+         tryRead("size", &lpl->zfs.size);
+         break;
+      case 'h':
+         tryRead("hdr_size", &lpl->zfs.header);
+         break;
+      case 'd':
+         tryRead("dbuf_size", &dbufSize);
+         tryRead("dnode_size", &dnodeSize);
+         break;
+      case 'b':
+         tryRead("bonus_size", &bonusSize);
+         break;
+      case 'a':
+         tryRead("anon_size", &lpl->zfs.anon);
+         break;
+      case 'm':
+         tryRead("mfu_size", &lpl->zfs.MFU);
+         tryRead("mru_size", &lpl->zfs.MRU);
+         break;
+      }
+      #undef tryRead
+      #undef tryReadFlag
+   }
+   fclose(file);
+
+   lpl->zfs.enabled = (lpl->zfs.size > 0 ? 1 : 0);
+   lpl->zfs.size    /= 1024;
+   lpl->zfs.min    /= 1024;
+   lpl->zfs.max    /= 1024;
+   lpl->zfs.MFU    /= 1024;
+   lpl->zfs.MRU    /= 1024;
+   lpl->zfs.anon   /= 1024;
+   lpl->zfs.header /= 1024;
+   lpl->zfs.other   = (dbufSize + dnodeSize + bonusSize) / 1024;
+   if ( lpl->zfs.isCompressed ) {
+      lpl->zfs.compressed /= 1024;
+      lpl->zfs.uncompressed /= 1024;
+   }
+}
+
+static inline double LinuxProcessList_scanCPUTime(ProcessList* super) {
+   LinuxProcessList* this = (LinuxProcessList*) super;
+
+   LinuxProcessList_updateCPUcount(super);
+
+   FILE* file = fopen(PROCSTATFILE, "r");
+   if (!file)
+      CRT_fatalError("Cannot open " PROCSTATFILE);
+
+   unsigned int existingCPUs = super->existingCPUs;
+   unsigned int lastAdjCpuId = 0;
+
+   for (unsigned int i = 0; i <= existingCPUs; i++) {
+      char buffer[PROC_LINE_LENGTH + 1];
+      unsigned long long int usertime, nicetime, systemtime, idletime;
+      unsigned long long int ioWait = 0, irq = 0, softIrq = 0, steal = 0, guest = 0, guestnice = 0;
+
+      const char* ok = fgets(buffer, sizeof(buffer), file);
+      if (!ok)
+         break;
+
+      // cpu fields are sorted first
+      if (!String_startsWith(buffer, "cpu"))
+         break;
+
+      // Depending on your kernel version,
+      // 5, 7, 8 or 9 of these fields will be set.
+      // The rest will remain at zero.
+      unsigned int adjCpuId;
+      if (i == 0) {
+         (void) sscanf(buffer,   "cpu  %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu",         &usertime, &nicetime, &systemtime, &idletime, &ioWait, &irq, &softIrq, &steal, &guest, &guestnice);
+         adjCpuId = 0;
+      } else {
+         unsigned int cpuid;
+         (void) sscanf(buffer, "cpu%4u %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu %16llu", &cpuid, &usertime, &nicetime, &systemtime, &idletime, &ioWait, &irq, &softIrq, &steal, &guest, &guestnice);
+         adjCpuId = cpuid + 1;
+      }
+
+      if (adjCpuId > super->existingCPUs)
+         break;
+
+      for (unsigned int j = lastAdjCpuId + 1; j < adjCpuId; j++) {
+         // Skipped an ID, but /proc/stat is ordered => got offline CPU
+         memset(&(this->cpuData[j]), '\0', sizeof(CPUData));
+      }
+      lastAdjCpuId = adjCpuId;
+
+      // Guest time is already accounted in usertime
+      usertime -= guest;
+      nicetime -= guestnice;
+      // Fields existing on kernels >= 2.6
+      // (and RHEL's patched kernel 2.4...)
+      unsigned long long int idlealltime = idletime + ioWait;
+      unsigned long long int systemalltime = systemtime + irq + softIrq;
+      unsigned long long int virtalltime = guest + guestnice;
+      unsigned long long int totaltime = usertime + nicetime + systemalltime + idlealltime + steal + virtalltime;
+      CPUData* cpuData = &(this->cpuData[adjCpuId]);
+      // Since we do a subtraction (usertime - guest) and cputime64_to_clock_t()
+      // used in /proc/stat rounds down numbers, it can lead to a case where the
+      // integer overflow.
+      cpuData->userPeriod = saturatingSub(usertime, cpuData->userTime);
+      cpuData->nicePeriod = saturatingSub(nicetime, cpuData->niceTime);
+      cpuData->systemPeriod = saturatingSub(systemtime, cpuData->systemTime);
+      cpuData->systemAllPeriod = saturatingSub(systemalltime, cpuData->systemAllTime);
+      cpuData->idleAllPeriod = saturatingSub(idlealltime, cpuData->idleAllTime);
+      cpuData->idlePeriod = saturatingSub(idletime, cpuData->idleTime);
+      cpuData->ioWaitPeriod = saturatingSub(ioWait, cpuData->ioWaitTime);
+      cpuData->irqPeriod = saturatingSub(irq, cpuData->irqTime);
+      cpuData->softIrqPeriod = saturatingSub(softIrq, cpuData->softIrqTime);
+      cpuData->stealPeriod = saturatingSub(steal, cpuData->stealTime);
+      cpuData->guestPeriod = saturatingSub(virtalltime, cpuData->guestTime);
+      cpuData->totalPeriod = saturatingSub(totaltime, cpuData->totalTime);
+      cpuData->userTime = usertime;
+      cpuData->niceTime = nicetime;
+      cpuData->systemTime = systemtime;
+      cpuData->systemAllTime = systemalltime;
+      cpuData->idleAllTime = idlealltime;
+      cpuData->idleTime = idletime;
+      cpuData->ioWaitTime = ioWait;
+      cpuData->irqTime = irq;
+      cpuData->softIrqTime = softIrq;
+      cpuData->stealTime = steal;
+      cpuData->guestTime = virtalltime;
+      cpuData->totalTime = totaltime;
+   }
+
+   double period = (double)this->cpuData[0].totalPeriod / super->activeCPUs;
+
+   char buffer[PROC_LINE_LENGTH + 1];
+   while (fgets(buffer, sizeof(buffer), file)) {
+      if (String_startsWith(buffer, "procs_running")) {
+         super->runningTasks = strtoul(buffer + strlen("procs_running"), NULL, 10);
+         break;
+      }
+   }
+
+   fclose(file);
+
+   return period;
+}
+
+static int scanCPUFrequencyFromSysCPUFreq(LinuxProcessList* this) {
+   unsigned int existingCPUs = this->super.existingCPUs;
+   int numCPUsWithFrequency = 0;
+   unsigned long totalFrequency = 0;
+
+   /*
+    * On some AMD and Intel CPUs read()ing scaling_cur_freq is quite slow (> 1ms). This delay
+    * accumulates for every core. For details see issue#471.
+    * If the read on CPU 0 takes longer than 500us bail out and fall back to reading the
+    * frequencies from /proc/cpuinfo.
+    * Once the condition has been met, bail out early for the next couple of scans.
+    */
+   static int timeout = 0;
+
+   if (timeout > 0) {
+      timeout--;
+      return -1;
+   }
+
+   for (unsigned int i = 0; i < existingCPUs; ++i) {
+      if (!ProcessList_isCPUonline(&this->super, i))
+         continue;
+
+      char pathBuffer[64];
+      xSnprintf(pathBuffer, sizeof(pathBuffer), "/sys/devices/system/cpu/cpu%u/cpufreq/scaling_cur_freq", i);
+
+      struct timespec start;
+      if (i == 0)
+         clock_gettime(CLOCK_MONOTONIC, &start);
+
+      FILE* file = fopen(pathBuffer, "r");
+      if (!file)
+         return -errno;
+
+      unsigned long frequency;
+      if (fscanf(file, "%lu", &frequency) == 1) {
+         /* convert kHz to MHz */
+         frequency = frequency / 1000;
+         this->cpuData[i + 1].frequency = frequency;
+         numCPUsWithFrequency++;
+         totalFrequency += frequency;
+      }
+
+      fclose(file);
+
+      if (i == 0) {
+         struct timespec end;
+         clock_gettime(CLOCK_MONOTONIC, &end);
+         const time_t timeTakenUs = (end.tv_sec - start.tv_sec) * 1000000 + (end.tv_nsec - start.tv_nsec) / 1000;
+         if (timeTakenUs > 500) {
+            timeout = 30;
+            return -1;
+         }
+      }
+
+   }
+
+   if (numCPUsWithFrequency > 0)
+      this->cpuData[0].frequency = (double)totalFrequency / numCPUsWithFrequency;
+
+   return 0;
+}
+
+static void scanCPUFrequencyFromCPUinfo(LinuxProcessList* this) {
+   FILE* file = fopen(PROCCPUINFOFILE, "r");
+   if (file == NULL)
+      return;
+
+   unsigned int existingCPUs = this->super.existingCPUs;
+   int numCPUsWithFrequency = 0;
+   double totalFrequency = 0;
+   int cpuid = -1;
+
+   while (!feof(file)) {
+      double frequency;
+      char buffer[PROC_LINE_LENGTH];
+
+      if (fgets(buffer, PROC_LINE_LENGTH, file) == NULL)
+         break;
+
+      if (sscanf(buffer, "processor : %d", &cpuid) == 1) {
+         continue;
+      } else if (
+         (sscanf(buffer, "cpu MHz : %lf", &frequency) == 1) ||
+         (sscanf(buffer, "clock : %lfMHz", &frequency) == 1)
+      ) {
+         if (cpuid < 0 || (unsigned int)cpuid > (existingCPUs - 1)) {
+            continue;
+         }
+
+         CPUData* cpuData = &(this->cpuData[cpuid + 1]);
+         /* do not override sysfs data */
+         if (isnan(cpuData->frequency)) {
+            cpuData->frequency = frequency;
+         }
+         numCPUsWithFrequency++;
+         totalFrequency += frequency;
+      } else if (buffer[0] == '\n') {
+         cpuid = -1;
+      }
+   }
+   fclose(file);
+
+   if (numCPUsWithFrequency > 0) {
+      this->cpuData[0].frequency = totalFrequency / numCPUsWithFrequency;
+   }
+}
+
+static void LinuxProcessList_scanCPUFrequency(LinuxProcessList* this) {
+   unsigned int existingCPUs = this->super.existingCPUs;
+
+   for (unsigned int i = 0; i <= existingCPUs; i++) {
+      this->cpuData[i].frequency = NAN;
+   }
+
+   if (scanCPUFrequencyFromSysCPUFreq(this) == 0) {
+      return;
+   }
+
+   scanCPUFrequencyFromCPUinfo(this);
+}
+
+void ProcessList_goThroughEntries(ProcessList* super, bool pauseProcessUpdate) {
+   LinuxProcessList* this = (LinuxProcessList*) super;
+   const Settings* settings = super->settings;
+
+   LinuxProcessList_scanMemoryInfo(super);
+   LinuxProcessList_scanHugePages(this);
+   LinuxProcessList_scanZfsArcstats(this);
+   LinuxProcessList_scanZramInfo(this);
+
+   double period = LinuxProcessList_scanCPUTime(super);
+
+   if (settings->showCPUFrequency) {
+      LinuxProcessList_scanCPUFrequency(this);
+   }
+
+   #ifdef HAVE_SENSORS_SENSORS_H
+   if (settings->showCPUTemperature)
+      LibSensors_getCPUTemperatures(this->cpuData, this->super.existingCPUs, this->super.activeCPUs);
+   #endif
+
+   // in pause mode only gather global data for meters (CPU/memory/...)
+   if (pauseProcessUpdate) {
+      return;
+   }
+
+   if (settings->ss->flags & PROCESS_FLAG_LINUX_AUTOGROUP) {
+      // Refer to sched(7) 'autogroup feature' section
+      // The kernel feature can be enabled/disabled through procfs at
+      // any time, so check for it at the start of each sample - only
+      // read from per-process procfs files if it's globally enabled.
+      this->haveAutogroup = LinuxProcess_isAutogroupEnabled();
+   } else {
+      this->haveAutogroup = false;
+   }
+
+   /* PROCDIR is an absolute path */
+   assert(PROCDIR[0] == '/');
+#ifdef HAVE_OPENAT
+   openat_arg_t rootFd = AT_FDCWD;
+#else
+   openat_arg_t rootFd = "";
+#endif
+
+   LinuxProcessList_recurseProcTree(this, rootFd, PROCDIR, NULL, period);
+}
+
+bool ProcessList_isCPUonline(const ProcessList* super, unsigned int id) {
+   assert(id < super->existingCPUs);
+
+   const LinuxProcessList* this = (const LinuxProcessList*) super;
+   return this->cpuData[id + 1].online;
+}