server/process.c

   1 /*
   2  * Server-side process management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  */
   6
   7 #include <assert.h>
   8 #include <limits.h>
   9 #include <string.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <sys/time.h>
  13 #include <unistd.h>
  14
  15 #include "winerror.h"
  16 #include "winbase.h"
  17 #include "winnt.h"
  18
  19 #include "server.h"
  20 #include "server/process.h"
  21 #include "server/thread.h"
  22
  23 /* reserved handle access rights */
  24 #define RESERVED_SHIFT         25
  25 #define RESERVED_INHERIT       (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
  26 #define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
  27 #define RESERVED_ALL           (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
  28
  29 /* global handle macros */
  30 #define HANDLE_OBFUSCATOR         0x544a4def
  31 #define HANDLE_IS_GLOBAL(h)       (((h) ^ HANDLE_OBFUSCATOR) < 0x10000)
  32 #define HANDLE_LOCAL_TO_GLOBAL(h) ((h) ^ HANDLE_OBFUSCATOR)
  33 #define HANDLE_GLOBAL_TO_LOCAL(h) ((h) ^ HANDLE_OBFUSCATOR)
  34
  35 struct handle_entry
  36 {
  37     struct object *ptr;
  38     unsigned int   access;
  39 };
  40
  41 /* process structure */
  42 struct process
  43 {
  44     struct object        obj;             /* object header */
  45     struct process      *next;            /* system-wide process list */
  46     struct process      *prev;
  47     struct thread       *thread_list;     /* head of the thread list */
  48     struct handle_entry *entries;         /* handle entry table */
  49     int                  handle_count;    /* nb of allocated handle entries */
  50     int                  handle_last;     /* last used handle entry */
  51     int                  exit_code;       /* process exit code */
  52     int                  running_threads; /* number of threads running in this process */
  53     struct timeval       start_time;      /* absolute time at process start */
  54     struct timeval       end_time;        /* absolute time at process end */
  55     int                  priority;        /* priority class */
  56     int                  affinity;        /* process affinity mask */
  57     struct object       *console_in;      /* console input */
  58     struct object       *console_out;     /* console output */
  59     struct new_process_request *info;     /* startup info (freed after startup) */
  60 };
  61
  62
  63 static struct process initial_process;
  64 static struct process *first_process = &initial_process;
  65 static int running_processes;
  66
  67 #define MIN_HANDLE_ENTRIES  32
  68
  69 /* process operations */
  70
  71 static void process_dump( struct object *obj, int verbose );
  72 static int process_signaled( struct object *obj, struct thread *thread );
  73 static void process_destroy( struct object *obj );
  74 static void free_handles( struct process *process );
  75 static int copy_handle_table( struct process *process, struct process *parent );
  76
  77 static const struct object_ops process_ops =
  78 {
  79     process_dump,
  80     add_queue,
  81     remove_queue,
  82     process_signaled,
  83     no_satisfied,
  84     no_read_fd,
  85     no_write_fd,
  86     no_flush,
  87     no_get_file_info,
  88     process_destroy
  89 };
  90
  91
  92 /* initialization of a process structure */
  93 static void init_process( struct process *process )
  94 {
  95     init_object( &process->obj, &process_ops, NULL );
  96     process->next            = NULL;
  97     process->prev            = NULL;
  98     process->thread_list     = NULL;
  99     process->exit_code       = 0x103;  /* STILL_ACTIVE */
 100     process->running_threads = 0;
 101     process->priority        = NORMAL_PRIORITY_CLASS;
 102     process->affinity        = 1;
 103     process->console_in      = NULL;
 104     process->console_out     = NULL;
 105     process->info            = NULL;
 106     gettimeofday( &process->start_time, NULL );
 107     /* alloc a handle for the process itself */
 108     alloc_handle( process, process, PROCESS_ALL_ACCESS, 0 );
 109 }
 110
 111 /* create the initial process */
 112 struct process *create_initial_process(void)
 113 {
 114     struct new_process_request *info;
 115
 116     copy_handle_table( &initial_process, NULL );
 117     init_process( &initial_process );
 118
 119     if (!alloc_console( &initial_process )) return NULL;
 120     if (!(info = mem_alloc( sizeof(*info) ))) return NULL;
 121     info->start_flags = STARTF_USESTDHANDLES;
 122     info->hstdin  = alloc_handle( &initial_process, initial_process.console_in,
 123                                   GENERIC_READ | GENERIC_WRITE | SYNCHRONIZE, 1 );
 124     info->hstdout = alloc_handle( &initial_process, initial_process.console_out,
 125                                   GENERIC_READ | GENERIC_WRITE | SYNCHRONIZE, 1 );
 126     info->hstderr = alloc_handle( &initial_process, initial_process.console_out,
 127                                   GENERIC_READ | GENERIC_WRITE | SYNCHRONIZE, 1 );
 128     initial_process.info = info;
 129     grab_object( &initial_process ); /* so that we never free it */
 130     return &initial_process;
 131
 132 }
 133
 134 /* create a new process */
 135 struct process *create_process( struct new_process_request *req )
 136 {
 137     struct process *process = NULL;
 138     struct process *parent = current->process;
 139
 140     if (!(process = mem_alloc( sizeof(*process) ))) return NULL;
 141     if (!copy_handle_table( process, req->inherit_all ? parent : NULL ))
 142     {
 143         free( process );
 144         return NULL;
 145     }
 146     init_process( process );
 147     if (parent->console_in) process->console_in = grab_object( parent->console_in );
 148     if (parent->console_out) process->console_out = grab_object( parent->console_out );
 149
 150     if (!(process->info = mem_alloc( sizeof(*process->info) ))) goto error;
 151     memcpy( process->info, req, sizeof(*req) );
 152
 153     if (!req->inherit_all && !(req->start_flags & STARTF_USESTDHANDLES))
 154     {
 155         process->info->hstdin  = duplicate_handle( parent, req->hstdin, process,
 156                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 157         process->info->hstdout = duplicate_handle( parent, req->hstdout, process,
 158                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 159         process->info->hstderr = duplicate_handle( parent, req->hstderr, process,
 160                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 161     }
 162
 163     process->next = first_process;
 164     first_process->prev = process;
 165     first_process = process;
 166     return process;
 167
 168  error:
 169     release_object( process );
 170     return NULL;
 171 }
 172
 173 /* destroy a process when its refcount is 0 */
 174 static void process_destroy( struct object *obj )
 175 {
 176     struct process *process = (struct process *)obj;
 177     assert( obj->ops == &process_ops );
 178     assert( process != &initial_process );
 179
 180     /* we can't have a thread remaining */
 181     assert( !process->thread_list );
 182     if (process->next) process->next->prev = process->prev;
 183     if (process->prev) process->prev->next = process->next;
 184     else first_process = process->next;
 185     free_console( process );
 186     free_handles( process );
 187     if (process->info) free( process->info );
 188     if (debug_level) memset( process, 0xbb, sizeof(process) );  /* catch errors */
 189     free( process );
 190 }
 191
 192 /* dump a process on stdout for debugging purposes */
 193 static void process_dump( struct object *obj, int verbose )
 194 {
 195     struct process *process = (struct process *)obj;
 196     assert( obj->ops == &process_ops );
 197
 198     printf( "Process next=%p prev=%p\n", process->next, process->prev );
 199 }
 200
 201 static int process_signaled( struct object *obj, struct thread *thread )
 202 {
 203     struct process *process = (struct process *)obj;
 204     return !process->running_threads;
 205 }
 206
 207
 208 /* get a process from an id (and increment the refcount) */
 209 struct process *get_process_from_id( void *id )
 210 {
 211     struct process *p = first_process;
 212     while (p && (p != id)) p = p->next;
 213     if (p) grab_object( p );
 214     else SET_ERROR( ERROR_INVALID_PARAMETER );
 215     return p;
 216 }
 217
 218 /* get a process from a handle (and increment the refcount) */
 219 struct process *get_process_from_handle( int handle, unsigned int access )
 220 {
 221     return (struct process *)get_handle_obj( current->process, handle,
 222                                              access, &process_ops );
 223 }
 224
 225 /* retrieve the initialization info for a new process */
 226 int get_process_init_info( struct process *process, struct init_process_reply *reply )
 227 {
 228     struct new_process_request *info;
 229     if (!(info = process->info)) return 0;
 230     process->info = NULL;
 231     reply->start_flags = info->start_flags;
 232     reply->hstdin      = info->hstdin;
 233     reply->hstdout     = info->hstdout;
 234     reply->hstderr     = info->hstderr;
 235     free( info );
 236     return 1;
 237 }
 238
 239 /* a process has been killed (i.e. its last thread died) */
 240 static void process_killed( struct process *process, int exit_code )
 241 {
 242     assert( !process->thread_list );
 243     process->exit_code = exit_code;
 244     gettimeofday( &process->end_time, NULL );
 245     wake_up( &process->obj, 0 );
 246     free_handles( process );
 247 }
 248
 249 /* free the process handle entries */
 250 static void free_handles( struct process *process )
 251 {
 252     struct handle_entry *entry;
 253     int handle;
 254
 255     if (!(entry = process->entries)) return;
 256     for (handle = 0; handle <= process->handle_last; handle++, entry++)
 257     {
 258         struct object *obj = entry->ptr;
 259         entry->ptr = NULL;
 260         if (obj) release_object( obj );
 261     }
 262     free( process->entries );
 263     process->handle_count = 0;
 264     process->handle_last  = -1;
 265     process->entries = NULL;
 266 }
 267
 268 /* add a thread to a process running threads list */
 269 void add_process_thread( struct process *process, struct thread *thread )
 270 {
 271     thread->proc_next = process->thread_list;
 272     thread->proc_prev = NULL;
 273     if (thread->proc_next) thread->proc_next->proc_prev = thread;
 274     process->thread_list = thread;
 275     if (!process->running_threads++) running_processes++;
 276     grab_object( thread );
 277 }
 278
 279 /* remove a thread from a process running threads list */
 280 void remove_process_thread( struct process *process, struct thread *thread )
 281 {
 282     assert( process->running_threads > 0 );
 283     assert( process->thread_list );
 284
 285     if (thread->proc_next) thread->proc_next->proc_prev = thread->proc_prev;
 286     if (thread->proc_prev) thread->proc_prev->proc_next = thread->proc_next;
 287     else process->thread_list = thread->proc_next;
 288
 289     if (!--process->running_threads)
 290     {
 291         /* we have removed the last running thread, exit the process */
 292         running_processes--;
 293         process_killed( process, thread->exit_code );
 294     }
 295     release_object( thread );
 296 }
 297
 298 /* grow a handle table */
 299 /* return 1 if OK, 0 on error */
 300 static int grow_handle_table( struct process *process )
 301 {
 302     struct handle_entry *new_entries;
 303     int count = process->handle_count;
 304
 305     if (count >= INT_MAX / 2) return 0;
 306     count *= 2;
 307     if (!(new_entries = realloc( process->entries, count * sizeof(struct handle_entry) )))
 308     {
 309         SET_ERROR( ERROR_OUTOFMEMORY );
 310         return 0;
 311     }
 312     process->handle_count = count;
 313     process->entries      = new_entries;
 314     return 1;
 315 }
 316
 317 /* allocate a handle for an object, incrementing its refcount */
 318 /* return the handle, or -1 on error */
 319 int alloc_handle( struct process *process, void *obj, unsigned int access,
 320                   int inherit )
 321 {
 322     struct handle_entry *entry;
 323     int handle;
 324
 325     assert( !(access & RESERVED_ALL) );
 326     if (inherit) access |= RESERVED_INHERIT;
 327
 328     /* find the first free entry */
 329
 330     if (!(entry = process->entries)) return -1;
 331     for (handle = 0; handle <= process->handle_last; handle++, entry++)
 332         if (!entry->ptr) goto found;
 333
 334     if (handle >= process->handle_count)
 335     {
 336         if (!grow_handle_table( process )) return -1;
 337         entry = process->entries + handle;  /* the table may have moved */
 338     }
 339     process->handle_last = handle;
 340
 341  found:
 342     entry->ptr    = grab_object( obj );
 343     entry->access = access;
 344     return handle + 1;  /* avoid handle 0 */
 345 }
 346
 347 /* return an handle entry, or NULL if the handle is invalid */
 348 static struct handle_entry *get_handle( struct process *process, int handle )
 349 {
 350     struct handle_entry *entry;
 351
 352     if (HANDLE_IS_GLOBAL(handle))
 353     {
 354         handle = HANDLE_GLOBAL_TO_LOCAL(handle);
 355         process = &initial_process;
 356     }
 357     handle--;  /* handles start at 1 */
 358     if ((handle < 0) || (handle > process->handle_last)) goto error;
 359     entry = process->entries + handle;
 360     if (!entry->ptr) goto error;
 361     return entry;
 362
 363  error:
 364     SET_ERROR( ERROR_INVALID_HANDLE );
 365     return NULL;
 366 }
 367
 368 /* attempt to shrink a table */
 369 /* return 1 if OK, 0 on error */
 370 static int shrink_handle_table( struct process *process )
 371 {
 372     struct handle_entry *new_entries;
 373     struct handle_entry *entry = process->entries + process->handle_last;
 374     int count = process->handle_count;
 375
 376     while (process->handle_last >= 0)
 377     {
 378         if (entry->ptr) break;
 379         process->handle_last--;
 380         entry--;
 381     }
 382     if (process->handle_last >= count / 4) return 1;  /* no need to shrink */
 383     if (count < MIN_HANDLE_ENTRIES * 2) return 1;  /* too small to shrink */
 384     count /= 2;
 385     if (!(new_entries = realloc( process->entries,
 386                                  count * sizeof(struct handle_entry) )))
 387         return 0;
 388     process->handle_count = count;
 389     process->entries      = new_entries;
 390     return 1;
 391 }
 392
 393 /* copy the handle table of the parent process */
 394 /* return 1 if OK, 0 on error */
 395 static int copy_handle_table( struct process *process, struct process *parent )
 396 {
 397     struct handle_entry *ptr;
 398     int i, count, last;
 399
 400     if (!parent)  /* first process */
 401     {
 402         count = MIN_HANDLE_ENTRIES;
 403         last  = -1;
 404     }
 405     else
 406     {
 407         assert( parent->entries );
 408         count = parent->handle_count;
 409         last  = parent->handle_last;
 410     }
 411
 412     if (!(ptr = mem_alloc( count * sizeof(struct handle_entry)))) return 0;
 413     process->entries      = ptr;
 414     process->handle_count = count;
 415     process->handle_last  = last;
 416
 417     if (last >= 0)
 418     {
 419         memcpy( ptr, parent->entries, (last + 1) * sizeof(struct handle_entry) );
 420         for (i = 0; i <= last; i++, ptr++)
 421         {
 422             if (!ptr->ptr) continue;
 423             if (ptr->access & RESERVED_INHERIT) grab_object( ptr->ptr );
 424             else ptr->ptr = NULL; /* don't inherit this entry */
 425         }
 426     }
 427     /* attempt to shrink the table */
 428     shrink_handle_table( process );
 429     return 1;
 430 }
 431
 432 /* close a handle and decrement the refcount of the associated object */
 433 /* return 1 if OK, 0 on error */
 434 int close_handle( struct process *process, int handle )
 435 {
 436     struct handle_entry *entry;
 437     struct object *obj;
 438
 439     if (HANDLE_IS_GLOBAL(handle))
 440     {
 441         handle = HANDLE_GLOBAL_TO_LOCAL(handle);
 442         process = &initial_process;
 443     }
 444     if (!(entry = get_handle( process, handle ))) return 0;
 445     if (entry->access & RESERVED_CLOSE_PROTECT) return 0;  /* FIXME: error code */
 446     obj = entry->ptr;
 447     entry->ptr = NULL;
 448     if (handle-1 == process->handle_last) shrink_handle_table( process );
 449     release_object( obj );
 450     return 1;
 451 }
 452
 453 /* retrieve the object corresponding to a handle, incrementing its refcount */
 454 struct object *get_handle_obj( struct process *process, int handle,
 455                                unsigned int access, const struct object_ops *ops )
 456 {
 457     struct handle_entry *entry;
 458     struct object *obj;
 459
 460     switch( handle )
 461     {
 462     case 0xfffffffe:  /* current thread pseudo-handle */
 463         obj = &current->obj;
 464         break;
 465     case 0x7fffffff:  /* current process pseudo-handle */
 466         obj = (struct object *)current->process;
 467         break;
 468     default:
 469         if (!(entry = get_handle( process, handle ))) return NULL;
 470         if ((entry->access & access) != access)
 471         {
 472             SET_ERROR( ERROR_ACCESS_DENIED );
 473             return NULL;
 474         }
 475         obj = entry->ptr;
 476         break;
 477     }
 478     if (ops && (obj->ops != ops))
 479     {
 480         SET_ERROR( ERROR_INVALID_HANDLE );  /* not the right type */
 481         return NULL;
 482     }
 483     return grab_object( obj );
 484 }
 485
 486 /* get/set the handle reserved flags */
 487 /* return the new flags (or -1 on error) */
 488 int set_handle_info( struct process *process, int handle, int mask, int flags )
 489 {
 490     struct handle_entry *entry;
 491
 492     if (!(entry = get_handle( process, handle ))) return -1;
 493     mask  = (mask << RESERVED_SHIFT) & RESERVED_ALL;
 494     flags = (flags << RESERVED_SHIFT) & mask;
 495     entry->access = (entry->access & ~mask) | flags;
 496     return (entry->access & RESERVED_ALL) >> RESERVED_SHIFT;
 497 }
 498
 499 /* duplicate a handle */
 500 int duplicate_handle( struct process *src, int src_handle, struct process *dst,
 501                       unsigned int access, int inherit, int options )
 502 {
 503     int res;
 504     struct handle_entry *entry = get_handle( src, src_handle );
 505     if (!entry) return -1;
 506
 507     if (options & DUP_HANDLE_SAME_ACCESS) access = entry->access;
 508     if (options & DUP_HANDLE_MAKE_GLOBAL) dst = &initial_process;
 509     access &= ~RESERVED_ALL;
 510     res = alloc_handle( dst, entry->ptr, access, inherit );
 511     if (options & DUP_HANDLE_MAKE_GLOBAL) res = HANDLE_LOCAL_TO_GLOBAL(res);
 512     return res;
 513 }
 514
 515 /* open a new handle to an existing object */
 516 int open_object( const char *name, const struct object_ops *ops,
 517                  unsigned int access, int inherit )
 518 {
 519     struct object *obj = find_object( name );
 520     if (!obj)
 521     {
 522         SET_ERROR( ERROR_FILE_NOT_FOUND );
 523         return -1;
 524     }
 525     if (ops && obj->ops != ops)
 526     {
 527         release_object( obj );
 528         SET_ERROR( ERROR_INVALID_HANDLE );  /* FIXME: not the right type */
 529         return -1;
 530     }
 531     return alloc_handle( current->process, obj, access, inherit );
 532 }
 533
 534 /* dump a handle table on stdout */
 535 void dump_handles( struct process *process )
 536 {
 537     struct handle_entry *entry;
 538     int i;
 539
 540     if (!process->entries) return;
 541     entry = process->entries;
 542     for (i = 0; i <= process->handle_last; i++, entry++)
 543     {
 544         if (!entry->ptr) continue;
 545         printf( "%5d: %p %08x ", i + 1, entry->ptr, entry->access );
 546         entry->ptr->ops->dump( entry->ptr, 0 );
 547     }
 548 }
 549
 550 /* kill a process on the spot */
 551 void kill_process( struct process *process, int exit_code )
 552 {
 553     while (process->thread_list)
 554         kill_thread( process->thread_list, exit_code );
 555 }
 556
 557 /* get all information about a process */
 558 void get_process_info( struct process *process,
 559                        struct get_process_info_reply *reply )
 560 {
 561     reply->pid              = process;
 562     reply->exit_code        = process->exit_code;
 563     reply->priority         = process->priority;
 564     reply->process_affinity = process->affinity;
 565     reply->system_affinity  = 1;
 566 }
 567
 568 /* set all information about a process */
 569 void set_process_info( struct process *process,
 570                        struct set_process_info_request *req )
 571 {
 572     if (req->mask & SET_PROCESS_INFO_PRIORITY)
 573         process->priority = req->priority;
 574     if (req->mask & SET_PROCESS_INFO_AFFINITY)
 575     {
 576         if (req->affinity != 1) SET_ERROR( ERROR_INVALID_PARAMETER );
 577         else process->affinity = req->affinity;
 578     }
 579 }
 580
 581 /* allocate a console for this process */
 582 int alloc_console( struct process *process )
 583 {
 584     struct object *obj[2];
 585     if (process->console_in || process->console_out)
 586     {
 587         SET_ERROR( ERROR_ACCESS_DENIED );
 588         return 0;
 589     }
 590     if (!create_console( -1, obj )) return 0;
 591     process->console_in  = obj[0];
 592     process->console_out = obj[1];
 593     return 1;
 594 }
 595
 596 /* free the console for this process */
 597 int free_console( struct process *process )
 598 {
 599     if (process->console_in) release_object( process->console_in );
 600     if (process->console_out) release_object( process->console_out );
 601     process->console_in = process->console_out = NULL;
 602     return 1;
 603 }
 604
 605 /* get the process console */
 606 struct object *get_console( struct process *process, int output )
 607 {
 608     struct object *obj;
 609     if (!(obj = output ? process->console_out : process->console_in))
 610         return NULL;
 611     return grab_object( obj );
 612 }
 613
 614 /* take a snapshot of currently running processes */
 615 struct process_snapshot *process_snap( int *count )
 616 {
 617     struct process_snapshot *snapshot, *ptr;
 618     struct process *process;
 619     if (!running_processes) return NULL;
 620     if (!(snapshot = mem_alloc( sizeof(*snapshot) * running_processes )))
 621         return NULL;
 622     ptr = snapshot;
 623     for (process = first_process; process; process = process->next)
 624     {
 625         if (!process->running_threads) continue;
 626         ptr->process  = process;
 627         ptr->threads  = process->running_threads;
 628         ptr->priority = process->priority;
 629         grab_object( process );
 630         ptr++;
 631     }
 632     *count = running_processes;
 633     return snapshot;
 634 }