apps/lib/libmeinos/proc.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU Lesser General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU Lesser General Public License for more details.
  14
  15     You should have received a copy of the GNU Lesser General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <sys/types.h>
  20 #include <sys/stat.h>
  21 #include <syscall.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/shm.h>
  25 #include <unistd.h>
  26 #include <pack.h>
  27
  28 size_t _fs_pack_filehandles(pack_t buf);
  29 void _fs_unpack_filehandles(pack_t buf);
  30
  31 /**
  32  * Gets name of a process
  33  *  @param pid PID of process
  34  *  @return Name of process (can be passed to free())
  35  */
  36 char *getname(pid_t pid) {
  37   size_t size = syscall_call(SYSCALL_PROC_GETNAME,3,pid,NULL,0);
  38   char *buf = malloc(size);
  39   syscall_call(SYSCALL_PROC_GETNAME,3,pid,buf,size);
  40   return buf;
  41 }
  42
  43 /**
  44  * Gets list of used pages
  45  *  @param pid PID of process to get list from
  46  *  @param _num_pages Reference for number of pages
  47  *  @return Array with pages (must be free()'d)
  48  */
  49 void **proc_mempagelist(pid_t pid,size_t *_num_pages) {
  50   ssize_t num_pages = syscall_call(SYSCALL_PROC_MEMPAGELIST,3,pid,NULL,0);
  51   if (num_pages>0) {
  52     void **pages = malloc(num_pages*sizeof(void*));
  53     *_num_pages = syscall_call(SYSCALL_PROC_MEMPAGELIST,3,pid,pages,num_pages);
  54     return pages;
  55   }
  56   else return NULL;
  57 }
  58
  59 /**
  60  * Pack process data
  61  *  @param argv Argument vector
  62  *  @param env Enviroment variables
  63  *  @return Var for new process
  64  */
  65 int proc_pack_procdata(char **argv,char **env,char *cwd,mode_t cmask) {
  66   size_t argv_size,fh_size,cwd_size,env_size,cmask_size,i;
  67   int shmid,argc,env_num;
  68   void *shmbuf;
  69   pack_t buf;
  70
  71   // prepare argv
  72   argv_size = sizeof(argc);
  73   if (argv!=NULL) {
  74     for (argc=0;argv[argc];argc++) argv_size += strlen(argv[argc])+1;
  75   }
  76   else argc = 0;
  77
  78   // prepare env
  79   env_size = sizeof(env_num);
  80   if (env!=NULL) {
  81     for (env_num=0;env[env_num];env_num++) env_size += strlen(env[env_num]);
  82   }
  83   else env_num = 0;
  84
  85   // prepare current workdir
  86   if (cwd==NULL) cwd = "/";
  87   cwd_size = strlen(cwd)+1;
  88
  89   // prepare creation mask
  90   cmask_size = sizeof(cmask);
  91
  92   // prepare filehandles
  93   fh_size = _fs_pack_filehandles(NULL);
  94
  95   // allocate space
  96   shmid = shmget(IPC_PRIVATE,argv_size+env_size+cwd_size+cmask_size+fh_size,0);
  97   if (shmid!=-1) {
  98     shmbuf = shmat(shmid,NULL,0);
  99     if (shmbuf!=NULL) {
 100       buf = pack_create(shmbuf);
 101
 102       // pack argv
 103       packi(buf,argc);
 104       for (i=0;i<argc;i++) packstr(buf,argv[i]);
 105       // pack env
 106       packi(buf,env_num);
 107       for (i=0;i<env_num;i++) packstr(buf,env[i]);
 108
 109       // pack current workdir
 110       packstr(buf,cwd);
 111
 112       // pack creation mask
 113       packi(buf,cmask);
 114
 115       // pack filehandles
 116       _fs_pack_filehandles(buf);
 117
 118       // release space
 119       pack_destroy(buf);
 120       shmdt(shmbuf);
 121       return shmid;
 122     }
 123     else shmctl(shmid,IPC_RMID,NULL);
 124   }
 125
 126   return -1;
 127 }
 128
 129 /**
 130  * Unpack process data
 131  *  @param var Var
 132  *  @param argv Reference for argument vector
 133  *  @param argc Reference for argument count
 134  *  @return Var for new process
 135  */
 136 int proc_unpack_procdata(int var,int *argc,char ***argv) {
 137   int ret;
 138   size_t i,env_num;
 139   char *cwd;
 140   void *shmbuf;
 141   pack_t buf;
 142   mode_t cmask;
 143
 144   // get space
 145   shmbuf = shmat(var,NULL,0);
 146   if (shmbuf!=NULL) {
 147     buf = pack_create(shmbuf);
 148
 149     // unpack argv
 150     unpacki(buf,argc);
 151     *argv = malloc(*argc*sizeof(char*));
 152     for (i=0;i<*argc;i++) unpackstr(buf,(*argv)+i);
 153     (*argv)[i] = NULL;
 154
 155     // unpack env
 156     unpacki(buf,&env_num);
 157     environ = malloc(env_num*sizeof(char*));
 158     for (i=0;i<env_num;i++) {
 159       char *tmp;
 160       unpackstr(buf,&tmp);
 161       environ[i] = strdup(tmp);
 162     }
 163     environ[i] = NULL;
 164
 165     // unpack current workdir
 166     unpackstr(buf,&cwd);
 167     chdir(cwd);
 168
 169     // unpack creation mask
 170     unpacki(buf,&cmask);
 171     umask(cmask);
 172
 173     // unpack filehandles
 174     _fs_unpack_filehandles(buf);
 175
 176     // free space
 177     pack_destroy(buf);
 178     shmdt(shmbuf);
 179     ret = var;
 180   }
 181   else ret = -1;
 182
 183   shmctl(var,IPC_RMID,NULL);
 184
 185   return ret;
 186 }