/*
htop - DarwinProcess.c
(C) 2015 Hisham H. Muhammad
Released under the GNU GPL, see the COPYING file
in the source distribution for its full text.
*/

#include "Process.h"
#include "DarwinProcess.h"

#include <stdlib.h>
#include <libproc.h>
#include <string.h>

/*{
#include "Settings.h"
#include <sys/sysctl.h>

}*/

Process* DarwinProcess_new(Settings* settings) {
   Process* this = calloc(sizeof(Process), 1);
   Object_setClass(this, Class(Process));
   Process_init(this, settings);
   return this;
}

void Process_delete(Object* cast) {
   Process* this = (Process*) cast;
   Object_setClass(this, Class(Process));
   Process_done((Process*)cast);
   // free platform-specific fields here
   free(this);
}

bool Process_isThread(Process* this) {
   return false;
}

void DarwinProcess_setStartTime(Process *proc, struct extern_proc *ep, time_t now) {
    struct tm date;

    proc->starttime_ctime = ep->p_starttime.tv_sec;
    (void) localtime_r(&proc->starttime_ctime, &date);
    strftime(proc->starttime_show, 7, ((proc->starttime_ctime > now - 86400) ? "%R " : "%b%d "), &date);
}

char *DarwinProcessList_getCmdLine(struct kinfo_proc* k, int show_args ) {
   /* This function is from the old Mac version of htop. Originally from ps? */
   int mib[3], argmax, nargs, c = 0;
   size_t size;
   char *procargs, *sp, *np, *cp, *retval;

   /* Get the maximum process arguments size. */
   mib[0] = CTL_KERN;
   mib[1] = KERN_ARGMAX;

   size = sizeof( argmax );
   if ( sysctl( mib, 2, &argmax, &size, NULL, 0 ) == -1 ) {
      goto ERROR_A;
   }

   /* Allocate space for the arguments. */
   procargs = ( char * ) malloc( argmax );
   if ( procargs == NULL ) {
      goto ERROR_A;
   }

   /*
    * Make a sysctl() call to get the raw argument space of the process.
    * The layout is documented in start.s, which is part of the Csu
    * project.  In summary, it looks like:
    *
    * /---------------\ 0x00000000
    * :               :
    * :               :
    * |---------------|
    * | argc          |
    * |---------------|
    * | arg[0]        |
    * |---------------|
    * :               :
    * :               :
    * |---------------|
    * | arg[argc - 1] |
    * |---------------|
    * | 0             |
    * |---------------|
    * | env[0]        |
    * |---------------|
    * :               :
    * :               :
    * |---------------|
    * | env[n]        |
    * |---------------|
    * | 0             |
    * |---------------| <-- Beginning of data returned by sysctl() is here.
    * | argc          |
    * |---------------|
    * | exec_path     |
    * |:::::::::::::::|
    * |               |
    * | String area.  |
    * |               |
    * |---------------| <-- Top of stack.
    * :               :
    * :               :
    * \---------------/ 0xffffffff
    */
   mib[0] = CTL_KERN;
   mib[1] = KERN_PROCARGS2;
   mib[2] = k->kp_proc.p_pid;

   size = ( size_t ) argmax;
   if ( sysctl( mib, 3, procargs, &size, NULL, 0 ) == -1 ) {
      goto ERROR_B;
   }

   memcpy( &nargs, procargs, sizeof( nargs ) );
   cp = procargs + sizeof( nargs );

   /* Skip the saved exec_path. */
   for ( ; cp < &procargs[size]; cp++ ) {
      if ( *cp == '\0' ) {
         /* End of exec_path reached. */
         break;
      }
   }
   if ( cp == &procargs[size] ) {
      goto ERROR_B;
   }

   /* Skip trailing '\0' characters. */
   for ( ; cp < &procargs[size]; cp++ ) {
      if ( *cp != '\0' ) {
         /* Beginning of first argument reached. */
         break;
      }
   }
   if ( cp == &procargs[size] ) {
      goto ERROR_B;
   }
   /* Save where the argv[0] string starts. */
   sp = cp;

   /*
    * Iterate through the '\0'-terminated strings and convert '\0' to ' '
    * until a string is found that has a '=' character in it (or there are
    * no more strings in procargs).  There is no way to deterministically
    * know where the command arguments end and the environment strings
    * start, which is why the '=' character is searched for as a heuristic.
    */
   for ( np = NULL; c < nargs && cp < &procargs[size]; cp++ ) {
      if ( *cp == '\0' ) {
         c++;
         if ( np != NULL ) {
            /* Convert previous '\0'. */
            *np = ' ';
         }
        /* Note location of current '\0'. */
        np = cp;

        if ( !show_args ) {
           /*
            * Don't convert '\0' characters to ' '.
            * However, we needed to know that the
            * command name was terminated, which we
            * now know.
            */
           break;
        }
     }
  }
#if 0
   /*
    * If eflg is non-zero, continue converting '\0' characters to ' '
    * characters until no more strings that look like environment settings
    * follow.
    */
   if ( ( eflg != 0 )
         && ( ( getuid(  ) == 0 )
              || ( k->kp_eproc.e_pcred.p_ruid == getuid(  ) ) ) ) {
      for ( ; cp < &procargs[size]; cp++ ) {
         if ( *cp == '\0' ) {
            if ( np != NULL ) {
               if ( &np[1] == cp ) {
                  /*
                   * Two '\0' characters in a row.
                   * This should normally only
                   * happen after all the strings
                   * have been seen, but in any
                   * case, stop parsing.
                   */
                  break;
               }
               /* Convert previous '\0'. */
               *np = ' ';
            }
           /* Note location of current '\0'. */
           np = cp;
        }
     }
  }
#endif

   /*
    * sp points to the beginning of the arguments/environment string, and
    * np should point to the '\0' terminator for the string.
    */
   if ( np == NULL || np == sp ) {
      /* Empty or unterminated string. */
      goto ERROR_B;
   }

   /* Make a copy of the string. */
   retval = strdup(sp);

   /* Clean up. */
   free( procargs );

   return retval;

ERROR_B:
   free( procargs );
ERROR_A:
   retval = strdup(k->kp_proc.p_comm);

   return retval;
}

void DarwinProcess_setFromKInfoProc(Process *proc, struct kinfo_proc *ps, time_t now, bool exists) {
    struct extern_proc *ep = &ps->kp_proc;

    /* UNSET HERE :
     *
     * processor
     * user (set at ProcessList level)
     * nlwp
     * percent_cpu
     * percent_mem
     * m_size
     * m_resident
     * minflt
     * majflt
     */

    /* First, the "immutable" parts */
    if(!exists) {
       /* Set the PID/PGID/etc. */
       proc->pid = ep->p_pid;
       proc->ppid = ps->kp_eproc.e_ppid;
       proc->pgrp = ps->kp_eproc.e_pgid;
       proc->session = 0; /* TODO Get the session id */
       proc->tgid = ps->kp_eproc.e_tpgid;
       proc->st_uid = ps->kp_eproc.e_ucred.cr_uid;
       /* e_tdev = (major << 24) | (minor & 0xffffff) */
       /* e_tdev == -1 for "no device" */
       proc->tty_nr = ps->kp_eproc.e_tdev & 0xff; /* TODO tty_nr is unsigned */

       DarwinProcess_setStartTime(proc, ep, now);

       /* The command is from the old Mac htop */
       char *slash;

       proc->comm = DarwinProcessList_getCmdLine(ps, false);
       slash = strrchr(proc->comm, '/');
       proc->basenameOffset = (NULL != slash) ? (slash - proc->comm) : 0;
    }

    /* Mutable information */
    proc->nice = ep->p_nice;
    proc->priority = ep->p_priority;

    /* Set the state */
    switch(ep->p_stat) {
    case SIDL:   proc->state = 'I'; break;
    case SRUN:   proc->state = 'R'; break;
    case SSLEEP: proc->state = 'S'; break;
    case SSTOP:  proc->state = 'T'; break;
    case SZOMB:  proc->state = 'Z'; break;
    default:     proc->state = '?'; break;
    }

    /* Make sure the updated flag is set */
    proc->updated = true;
}

void DarwinProcess_setFromLibprocPidinfo(Process *proc, uint64_t total_memory, bool preExisting) {
    struct proc_taskinfo pti;

    if(sizeof(pti) == proc_pidinfo(proc->pid, PROC_PIDTASKINFO, 0, &pti, sizeof(pti))) {
        proc->nlwp = pti.pti_threadnum;
        proc->m_size = pti.pti_virtual_size / 1024;
        proc->m_resident = pti.pti_resident_size / 1024;
        proc->majflt = pti.pti_faults;
        proc->percent_mem = (double)pti.pti_resident_size * 100.0 / (double)total_memory;
    }
}

void DarwinProcess_parseThreads(Process *proc, time_t now, bool preExisting) {
    static const size_t IDS_SZ = sizeof(uint64_t) * 2048;

    uint64_t *thread_ids = (uint64_t *)malloc(IDS_SZ);
    size_t bytes = proc_pidinfo(proc->pid, PROC_PIDLISTTHREADS, 0, thread_ids, IDS_SZ);

    if(0 < bytes) {
        size_t count = bytes / sizeof(uint64_t);

        proc->nlwp = count;
    }

    free(thread_ids); /* TODO Keep reusing this block */
}