/*
htop - Process.c
(C) 2004-2015 Hisham H. Muhammad
(C) 2020 Red Hat, Inc.  All Rights Reserved.
Released under the GNU GPLv2, see the COPYING file
in the source distribution for its full text.
*/

#include "config.h" // IWYU pragma: keep

#include "Process.h"

#include <assert.h>
#include <limits.h>
#include <math.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <sys/resource.h>

#include "CRT.h"
#include "Macros.h"
#include "Platform.h"
#include "ProcessList.h"
#include "RichString.h"
#include "Settings.h"
#include "XUtils.h"

#if defined(MAJOR_IN_MKDEV)
#include <sys/mkdev.h>
#elif defined(MAJOR_IN_SYSMACROS)
#include <sys/sysmacros.h>
#endif


static uid_t Process_getuid = (uid_t)-1;

int Process_pidDigits = 7;

void Process_setupColumnWidths() {
   int maxPid = Platform_getMaxPid();
   if (maxPid == -1)
      return;

   Process_pidDigits = ceil(log10(maxPid));
   assert(Process_pidDigits <= PROCESS_MAX_PID_DIGITS);
}

void Process_humanNumber(RichString* str, unsigned long long number, bool coloring) {
   char buffer[10];
   int len;

   int largeNumberColor = coloring ? CRT_colors[LARGE_NUMBER] : CRT_colors[PROCESS];
   int processMegabytesColor = coloring ? CRT_colors[PROCESS_MEGABYTES] : CRT_colors[PROCESS];
   int processGigabytesColor = coloring ? CRT_colors[PROCESS_GIGABYTES] : CRT_colors[PROCESS];
   int shadowColor = coloring ? CRT_colors[PROCESS_SHADOW] : CRT_colors[PROCESS];
   int processColor = CRT_colors[PROCESS];

   if (number == ULLONG_MAX) {
      //Invalid number
      RichString_appendAscii(str, shadowColor, "  N/A ");
   } else if (number < 1000) {
      //Plain number, no markings
      len = xSnprintf(buffer, sizeof(buffer), "%5llu ", number);
      RichString_appendnAscii(str, processColor, buffer, len);
   } else if (number < 100000) {
      //2 digit MB, 3 digit KB
      len = xSnprintf(buffer, sizeof(buffer), "%2llu", number/1000);
      RichString_appendnAscii(str, processMegabytesColor, buffer, len);
      number %= 1000;
      len = xSnprintf(buffer, sizeof(buffer), "%03llu ", number);
      RichString_appendnAscii(str, processColor, buffer, len);
   } else if (number < 1000 * ONE_K) {
      //3 digit MB
      number /= ONE_K;
      len = xSnprintf(buffer, sizeof(buffer), "%4lluM ", number);
      RichString_appendnAscii(str, processMegabytesColor, buffer, len);
   } else if (number < 10000 * ONE_K) {
      //1 digit GB, 3 digit MB
      number /= ONE_K;
      len = xSnprintf(buffer, sizeof(buffer), "%1llu", number/1000);
      RichString_appendnAscii(str, processGigabytesColor, buffer, len);
      number %= 1000;
      len = xSnprintf(buffer, sizeof(buffer), "%03lluM ", number);
      RichString_appendnAscii(str, processMegabytesColor, buffer, len);
   } else if (number < 100000 * ONE_K) {
      //2 digit GB, 1 digit MB
      number /= 100 * ONE_K;
      len = xSnprintf(buffer, sizeof(buffer), "%2llu", number/10);
      RichString_appendnAscii(str, processGigabytesColor, buffer, len);
      number %= 10;
      len = xSnprintf(buffer, sizeof(buffer), ".%1llu", number);
      RichString_appendnAscii(str, processMegabytesColor, buffer, len);
      RichString_appendAscii(str, processGigabytesColor, "G ");
   } else if (number < 1000 * ONE_M) {
      //3 digit GB
      number /= ONE_M;
      len = xSnprintf(buffer, sizeof(buffer), "%4lluG ", number);
      RichString_appendnAscii(str, processGigabytesColor, buffer, len);
   } else if (number < 10000ULL * ONE_M) {
      //1 digit TB, 3 digit GB
      number /= ONE_M;
      len = xSnprintf(buffer, sizeof(buffer), "%1llu", number/1000);
      RichString_appendnAscii(str, largeNumberColor, buffer, len);
      number %= 1000;
      len = xSnprintf(buffer, sizeof(buffer), "%03lluG ", number);
      RichString_appendnAscii(str, processGigabytesColor, buffer, len);
   } else {
      //2 digit TB and above
      len = xSnprintf(buffer, sizeof(buffer), "%4.1lfT ", (double)number/ONE_G);
      RichString_appendnAscii(str, largeNumberColor, buffer, len);
   }
}

void Process_colorNumber(RichString* str, unsigned long long number, bool coloring) {
   char buffer[13];

   int largeNumberColor = coloring ? CRT_colors[LARGE_NUMBER] : CRT_colors[PROCESS];
   int processMegabytesColor = coloring ? CRT_colors[PROCESS_MEGABYTES] : CRT_colors[PROCESS];
   int processColor = CRT_colors[PROCESS];
   int processShadowColor = coloring ? CRT_colors[PROCESS_SHADOW] : CRT_colors[PROCESS];

   if (number == ULLONG_MAX) {
      RichString_appendAscii(str, CRT_colors[PROCESS_SHADOW], "        N/A ");
   } else if (number >= 100000LL * ONE_DECIMAL_T) {
      xSnprintf(buffer, sizeof(buffer), "%11llu ", number / ONE_DECIMAL_G);
      RichString_appendnAscii(str, largeNumberColor, buffer, 12);
   } else if (number >= 100LL * ONE_DECIMAL_T) {
      xSnprintf(buffer, sizeof(buffer), "%11llu ", number / ONE_DECIMAL_M);
      RichString_appendnAscii(str, largeNumberColor, buffer, 8);
      RichString_appendnAscii(str, processMegabytesColor, buffer+8, 4);
   } else if (number >= 10LL * ONE_DECIMAL_G) {
      xSnprintf(buffer, sizeof(buffer), "%11llu ", number / ONE_DECIMAL_K);
      RichString_appendnAscii(str, largeNumberColor, buffer, 5);
      RichString_appendnAscii(str, processMegabytesColor, buffer+5, 3);
      RichString_appendnAscii(str, processColor, buffer+8, 4);
   } else {
      xSnprintf(buffer, sizeof(buffer), "%11llu ", number);
      RichString_appendnAscii(str, largeNumberColor, buffer, 2);
      RichString_appendnAscii(str, processMegabytesColor, buffer+2, 3);
      RichString_appendnAscii(str, processColor, buffer+5, 3);
      RichString_appendnAscii(str, processShadowColor, buffer+8, 4);
   }
}

void Process_printTime(RichString* str, unsigned long long totalHundredths) {
   unsigned long long totalSeconds = totalHundredths / 100;

   unsigned long long hours = totalSeconds / 3600;
   int minutes = (totalSeconds / 60) % 60;
   int seconds = totalSeconds % 60;
   int hundredths = totalHundredths - (totalSeconds * 100);
   char buffer[10];
   if (hours >= 100) {
      xSnprintf(buffer, sizeof(buffer), "%7lluh ", hours);
      RichString_appendAscii(str, CRT_colors[LARGE_NUMBER], buffer);
   } else {
      if (hours) {
         xSnprintf(buffer, sizeof(buffer), "%2lluh", hours);
         RichString_appendAscii(str, CRT_colors[LARGE_NUMBER], buffer);
         xSnprintf(buffer, sizeof(buffer), "%02d:%02d ", minutes, seconds);
      } else {
         xSnprintf(buffer, sizeof(buffer), "%2d:%02d.%02d ", minutes, seconds, hundredths);
      }
      RichString_appendAscii(str, CRT_colors[DEFAULT_COLOR], buffer);
   }
}

void Process_fillStarttimeBuffer(Process* this) {
   struct tm date;
   (void) localtime_r(&this->starttime_ctime, &date);
   strftime(this->starttime_show, sizeof(this->starttime_show) - 1, (this->starttime_ctime > (time(NULL) - 86400)) ? "%R " : "%b%d ", &date);
}

static inline void Process_writeCommand(const Process* this, int attr, int baseattr, RichString* str) {
   int start = RichString_size(str);
   int len = 0;
   const char* comm = this->comm;

   if (this->settings->highlightBaseName || !this->settings->showProgramPath) {
      int basename = 0;
      for (int i = 0; i < this->basenameOffset; i++) {
         if (comm[i] == '/') {
            basename = i + 1;
         } else if (comm[i] == ':') {
            len = i + 1;
            break;
         }
      }
      if (len == 0) {
         if (this->settings->showProgramPath) {
            start += basename;
         } else {
            comm += basename;
         }
         len = this->basenameOffset - basename;
      }
   }

   RichString_appendWide(str, attr, comm);

   if (this->settings->highlightBaseName) {
      RichString_setAttrn(str, baseattr, start, len);
   }
}

void Process_outputRate(RichString* str, char* buffer, size_t n, double rate, int coloring) {
   int largeNumberColor = CRT_colors[LARGE_NUMBER];
   int processMegabytesColor = CRT_colors[PROCESS_MEGABYTES];
   int processColor = CRT_colors[PROCESS];

   if (!coloring) {
      largeNumberColor = CRT_colors[PROCESS];
      processMegabytesColor = CRT_colors[PROCESS];
   }

   if (isnan(rate)) {
      RichString_appendAscii(str, CRT_colors[PROCESS_SHADOW], "        N/A ");
   } else if (rate < ONE_K) {
      int len = snprintf(buffer, n, "%7.2f B/s ", rate);
      RichString_appendnAscii(str, processColor, buffer, len);
   } else if (rate < ONE_M) {
      int len = snprintf(buffer, n, "%7.2f K/s ", rate / ONE_K);
      RichString_appendnAscii(str, processColor, buffer, len);
   } else if (rate < ONE_G) {
      int len = snprintf(buffer, n, "%7.2f M/s ", rate / ONE_M);
      RichString_appendnAscii(str, processMegabytesColor, buffer, len);
   } else if (rate < ONE_T) {
      int len = snprintf(buffer, n, "%7.2f G/s ", rate / ONE_G);
      RichString_appendnAscii(str, largeNumberColor, buffer, len);
   } else {
      int len = snprintf(buffer, n, "%7.2f T/s ", rate / ONE_T);
      RichString_appendnAscii(str, largeNumberColor, buffer, len);
   }
}

void Process_printLeftAlignedField(RichString* str, int attr, const char* content, unsigned int width) {
   int columns = width;
   RichString_appendnWideColumns(str, attr, content, strlen(content), &columns);
   RichString_appendChr(str, attr, ' ', width + 1 - columns);
}

void Process_writeField(const Process* this, RichString* str, ProcessField field) {
   char buffer[256];
   size_t n = sizeof(buffer);
   int attr = CRT_colors[DEFAULT_COLOR];
   bool coloring = this->settings->highlightMegabytes;

   switch (field) {
   case COMM: {
      int baseattr = CRT_colors[PROCESS_BASENAME];
      if (this->settings->highlightThreads && Process_isThread(this)) {
         attr = CRT_colors[PROCESS_THREAD];
         baseattr = CRT_colors[PROCESS_THREAD_BASENAME];
      }
      if (!this->settings->treeView || this->indent == 0) {
         Process_writeCommand(this, attr, baseattr, str);
         return;
      }

      char* buf = buffer;
      int maxIndent = 0;
      bool lastItem = (this->indent < 0);
      int indent = (this->indent < 0 ? -this->indent : this->indent);

      for (int i = 0; i < 32; i++) {
         if (indent & (1U << i)) {
            maxIndent = i+1;
         }
      }

      for (int i = 0; i < maxIndent - 1; i++) {
         int written, ret;
         if (indent & (1 << i)) {
            ret = xSnprintf(buf, n, "%s  ", CRT_treeStr[TREE_STR_VERT]);
         } else {
            ret = xSnprintf(buf, n, "   ");
         }
         if (ret < 0 || (size_t)ret >= n) {
            written = n;
         } else {
            written = ret;
         }
         buf += written;
         n -= written;
      }

      const char* draw = CRT_treeStr[lastItem ? TREE_STR_BEND : TREE_STR_RTEE];
      xSnprintf(buf, n, "%s%s ", draw, this->showChildren ? CRT_treeStr[TREE_STR_SHUT] : CRT_treeStr[TREE_STR_OPEN] );
      RichString_appendWide(str, CRT_colors[PROCESS_TREE], buffer);
      Process_writeCommand(this, attr, baseattr, str);
      return;
   }
   case MAJFLT: Process_colorNumber(str, this->majflt, coloring); return;
   case MINFLT: Process_colorNumber(str, this->minflt, coloring); return;
   case M_RESIDENT: Process_humanNumber(str, this->m_resident, coloring); return;
   case M_VIRT: Process_humanNumber(str, this->m_virt, coloring); return;
   case NICE:
      xSnprintf(buffer, n, "%3ld ", this->nice);
      attr = this->nice < 0 ? CRT_colors[PROCESS_HIGH_PRIORITY]
           : this->nice > 0 ? CRT_colors[PROCESS_LOW_PRIORITY]
           : CRT_colors[PROCESS_SHADOW];
      break;
   case NLWP:
      if (this->nlwp == 1)
         attr = CRT_colors[PROCESS_SHADOW];

      xSnprintf(buffer, n, "%4ld ", this->nlwp);
      break;
   case PERCENT_CPU:
   case PERCENT_NORM_CPU: {
      float cpuPercentage = this->percent_cpu;
      if (field == PERCENT_NORM_CPU) {
         cpuPercentage /= this->processList->cpuCount;
      }
      if (cpuPercentage > 999.9F) {
         xSnprintf(buffer, n, "%4u ", (unsigned int)cpuPercentage);
      } else if (cpuPercentage > 99.9F) {
         xSnprintf(buffer, n, "%3u. ", (unsigned int)cpuPercentage);
      } else {
         if (cpuPercentage < 0.05F)
            attr = CRT_colors[PROCESS_SHADOW];

         xSnprintf(buffer, n, "%4.1f ", cpuPercentage);
      }
      break;
   }
   case PERCENT_MEM:
      if (this->percent_mem > 99.9F) {
         xSnprintf(buffer, n, "100. ");
      } else {
         if (this->percent_mem < 0.05F)
            attr = CRT_colors[PROCESS_SHADOW];

         xSnprintf(buffer, n, "%4.1f ", this->percent_mem);
      }
      break;
   case PGRP: xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->pgrp); break;
   case PID: xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->pid); break;
   case PPID: xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->ppid); break;
   case PRIORITY:
      if (this->priority <= -100)
         xSnprintf(buffer, n, " RT ");
      else
         xSnprintf(buffer, n, "%3ld ", this->priority);
      break;
   case PROCESSOR: xSnprintf(buffer, n, "%3d ", Settings_cpuId(this->settings, this->processor)); break;
   case SESSION: xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->session); break;
   case STARTTIME: xSnprintf(buffer, n, "%s", this->starttime_show); break;
   case STATE:
      xSnprintf(buffer, n, "%c ", this->state);
      switch (this->state) {
         case 'R':
            attr = CRT_colors[PROCESS_R_STATE];
            break;
         case 'D':
            attr = CRT_colors[PROCESS_D_STATE];
            break;
         case 'I':
         case 'S':
            attr = CRT_colors[PROCESS_SHADOW];
            break;
      }
      break;
   case ST_UID: xSnprintf(buffer, n, "%5d ", this->st_uid); break;
   case TIME: Process_printTime(str, this->time); return;
   case TGID:
      if (this->tgid == this->pid)
         attr = CRT_colors[PROCESS_SHADOW];

      xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->tgid);
      break;
   case TPGID: xSnprintf(buffer, n, "%*d ", Process_pidDigits, this->tpgid); break;
   case TTY_NR: {
      unsigned int major = major(this->tty_nr);
      unsigned int minor = minor(this->tty_nr);
      if (major == 0 && minor == 0) {
         attr = CRT_colors[PROCESS_SHADOW];
         xSnprintf(buffer, n, "(none)   ");
      } else {
         xSnprintf(buffer, n, "%3u:%3u  ", major, minor);
      }
      break;
   }
   case USER:
      if (Process_getuid != this->st_uid)
         attr = CRT_colors[PROCESS_SHADOW];

      if (this->user) {
         Process_printLeftAlignedField(str, attr, this->user, 9);
         return;
      }

      xSnprintf(buffer, n, "%-9d ", this->st_uid);
      break;
   default:
      assert(0); /* should never be reached */
      xSnprintf(buffer, n, "- ");
   }
   RichString_appendWide(str, attr, buffer);
}

void Process_display(const Object* cast, RichString* out) {
   const Process* this = (const Process*) cast;
   const ProcessField* fields = this->settings->fields;
   for (int i = 0; fields[i]; i++)
      As_Process(this)->writeField(this, out, fields[i]);

   if (this->settings->shadowOtherUsers && this->st_uid != Process_getuid) {
      RichString_setAttr(out, CRT_colors[PROCESS_SHADOW]);
   }

   if (this->tag == true) {
      RichString_setAttr(out, CRT_colors[PROCESS_TAG]);
   }

   if (this->settings->highlightChanges) {
      if (Process_isTomb(this)) {
         out->highlightAttr = CRT_colors[PROCESS_TOMB];
      } else if (Process_isNew(this)) {
         out->highlightAttr = CRT_colors[PROCESS_NEW];
      }
   }

   assert(RichString_size(out) > 0);
}

void Process_done(Process* this) {
   assert (this != NULL);
   free(this->comm);
}

static const char* Process_getCommandStr(const Process* p) {
   return p->comm ? p->comm : "";
}

const ProcessClass Process_class = {
   .super = {
      .extends = Class(Object),
      .display = Process_display,
      .delete = Process_delete,
      .compare = Process_compare
   },
   .writeField = Process_writeField,
   .getCommandStr = Process_getCommandStr,
};

void Process_init(Process* this, const Settings* settings) {
   this->settings = settings;
   this->tag = false;
   this->showChildren = true;
   this->show = true;
   this->updated = false;
   this->basenameOffset = -1;

   if (Process_getuid == (uid_t)-1) {
      Process_getuid = getuid();
   }
}

void Process_toggleTag(Process* this) {
   this->tag = !this->tag;
}

bool Process_isNew(const Process* this) {
   assert(this->processList);
   if (this->processList->monotonicMs >= this->seenStampMs) {
      return this->processList->monotonicMs - this->seenStampMs <= 1000 * (uint64_t)this->processList->settings->highlightDelaySecs;
   }
   return false;
}

bool Process_isTomb(const Process* this) {
    return this->tombStampMs > 0;
}

bool Process_setPriority(Process* this, int priority) {
   int old_prio = getpriority(PRIO_PROCESS, this->pid);
   int err = setpriority(PRIO_PROCESS, this->pid, priority);

   if (err == 0 && old_prio != getpriority(PRIO_PROCESS, this->pid)) {
      this->nice = priority;
   }
   return (err == 0);
}

bool Process_changePriorityBy(Process* this, Arg delta) {
   return Process_setPriority(this, this->nice + delta.i);
}

bool Process_sendSignal(Process* this, Arg sgn) {
   return kill(this->pid, sgn.i) == 0;
}

int Process_pidCompare(const void* v1, const void* v2) {
   const Process* p1 = (const Process*)v1;
   const Process* p2 = (const Process*)v2;

   return SPACESHIP_NUMBER(p1->pid, p2->pid);
}

int Process_compare(const void* v1, const void* v2) {
   const Process *p1 = (const Process*)v1;
   const Process *p2 = (const Process*)v2;

   const Settings *settings = p1->settings;

   ProcessField key = Settings_getActiveSortKey(settings);

   int result = Process_compareByKey(p1, p2, key);

   // Implement tie-breaker (needed to make tree mode more stable)
   if (!result)
      return SPACESHIP_NUMBER(p1->pid, p2->pid);

   return (Settings_getActiveDirection(settings) == 1) ? result : -result;
}

static uint8_t stateCompareValue(char state) {
   switch (state) {

   case 'S':
      return 10;

   case 'I':
      return 9;

   case 'X':
      return 8;

   case 'Z':
      return 7;

   case 't':
      return 6;

   case 'T':
      return 5;

   case 'L':
      return 4;

   case 'D':
      return 3;

   case 'R':
      return 2;

   case '?':
      return 1;

   default:
      return 0;
   }
}

int Process_compareByKey_Base(const Process* p1, const Process* p2, ProcessField key) {
   int r;

   switch (key) {
   case PERCENT_CPU:
   case PERCENT_NORM_CPU:
      return SPACESHIP_NUMBER(p1->percent_cpu, p2->percent_cpu);
   case PERCENT_MEM:
      return SPACESHIP_NUMBER(p1->m_resident, p2->m_resident);
   case COMM:
      return SPACESHIP_NULLSTR(Process_getCommand(p1), Process_getCommand(p2));
   case MAJFLT:
      return SPACESHIP_NUMBER(p1->majflt, p2->majflt);
   case MINFLT:
      return SPACESHIP_NUMBER(p1->minflt, p2->minflt);
   case M_RESIDENT:
      return SPACESHIP_NUMBER(p1->m_resident, p2->m_resident);
   case M_VIRT:
      return SPACESHIP_NUMBER(p1->m_virt, p2->m_virt);
   case NICE:
      return SPACESHIP_NUMBER(p1->nice, p2->nice);
   case NLWP:
      return SPACESHIP_NUMBER(p1->nlwp, p2->nlwp);
   case PGRP:
      return SPACESHIP_NUMBER(p1->pgrp, p2->pgrp);
   case PID:
      return SPACESHIP_NUMBER(p1->pid, p2->pid);
   case PPID:
      return SPACESHIP_NUMBER(p1->ppid, p2->ppid);
   case PRIORITY:
      return SPACESHIP_NUMBER(p1->priority, p2->priority);
   case PROCESSOR:
      return SPACESHIP_NUMBER(p1->processor, p2->processor);
   case SESSION:
      return SPACESHIP_NUMBER(p1->session, p2->session);
   case STARTTIME:
      r = SPACESHIP_NUMBER(p1->starttime_ctime, p2->starttime_ctime);
      return r != 0 ? r : SPACESHIP_NUMBER(p1->pid, p2->pid);
   case STATE:
      return SPACESHIP_NUMBER(stateCompareValue(p1->state), stateCompareValue(p2->state));
   case ST_UID:
      return SPACESHIP_NUMBER(p1->st_uid, p2->st_uid);
   case TIME:
      return SPACESHIP_NUMBER(p1->time, p2->time);
   case TGID:
      return SPACESHIP_NUMBER(p1->tgid, p2->tgid);
   case TPGID:
      return SPACESHIP_NUMBER(p1->tpgid, p2->tpgid);
   case TTY_NR:
      return SPACESHIP_NUMBER(p1->tty_nr, p2->tty_nr);
   case USER:
      return SPACESHIP_NULLSTR(p1->user, p2->user);
   default:
      return SPACESHIP_NUMBER(p1->pid, p2->pid);
   }
}