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     info->env_ptr = NULL;
 129     initial_process.info = info;
 130     grab_object( &initial_process ); /* so that we never free it */
 131     return &initial_process;
 132
 133 }
 134
 135 /* create a new process */
 136 struct process *create_process( struct new_process_request *req )
 137 {
 138     struct process *process = NULL;
 139     struct process *parent = current->process;
 140
 141     if (!(process = mem_alloc( sizeof(*process) ))) return NULL;
 142     if (!copy_handle_table( process, req->inherit_all ? parent : NULL ))
 143     {
 144         free( process );
 145         return NULL;
 146     }
 147     init_process( process );
 148     if (parent->console_in) process->console_in = grab_object( parent->console_in );
 149     if (parent->console_out) process->console_out = grab_object( parent->console_out );
 150
 151     if (!(process->info = mem_alloc( sizeof(*process->info) ))) goto error;
 152     memcpy( process->info, req, sizeof(*req) );
 153
 154     if (!req->inherit_all && !(req->start_flags & STARTF_USESTDHANDLES))
 155     {
 156         process->info->hstdin  = duplicate_handle( parent, req->hstdin, process,
 157                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 158         process->info->hstdout = duplicate_handle( parent, req->hstdout, process,
 159                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 160         process->info->hstderr = duplicate_handle( parent, req->hstderr, process,
 161                                                    0, TRUE, DUPLICATE_SAME_ACCESS );
 162     }
 163
 164     process->next = first_process;
 165     first_process->prev = process;
 166     first_process = process;
 167     return process;
 168
 169  error:
 170     release_object( process );
 171     return NULL;
 172 }
 173
 174 /* destroy a process when its refcount is 0 */
 175 static void process_destroy( struct object *obj )
 176 {
 177     struct process *process = (struct process *)obj;
 178     assert( obj->ops == &process_ops );
 179     assert( process != &initial_process );
 180
 181     /* we can't have a thread remaining */
 182     assert( !process->thread_list );
 183     if (process->next) process->next->prev = process->prev;
 184     if (process->prev) process->prev->next = process->next;
 185     else first_process = process->next;
 186     free_console( process );
 187     free_handles( process );
 188     if (process->info) free( process->info );
 189     if (debug_level) memset( process, 0xbb, sizeof(process) );  /* catch errors */
 190     free( process );
 191 }
 192
 193 /* dump a process on stdout for debugging purposes */
 194 static void process_dump( struct object *obj, int verbose )
 195 {
 196     struct process *process = (struct process *)obj;
 197     assert( obj->ops == &process_ops );
 198
 199     printf( "Process next=%p prev=%p\n", process->next, process->prev );
 200 }
 201
 202 static int process_signaled( struct object *obj, struct thread *thread )
 203 {
 204     struct process *process = (struct process *)obj;
 205     return !process->running_threads;
 206 }
 207
 208
 209 /* get a process from an id (and increment the refcount) */
 210 struct process *get_process_from_id( void *id )
 211 {
 212     struct process *p = first_process;
 213     while (p && (p != id)) p = p->next;
 214     if (p) grab_object( p );
 215     else SET_ERROR( ERROR_INVALID_PARAMETER );
 216     return p;
 217 }
 218
 219 /* get a process from a handle (and increment the refcount) */
 220 struct process *get_process_from_handle( int handle, unsigned int access )
 221 {
 222     return (struct process *)get_handle_obj( current->process, handle,
 223                                              access, &process_ops );
 224 }
 225
 226 /* retrieve the initialization info for a new process */
 227 int get_process_init_info( struct process *process, struct init_process_reply *reply )
 228 {
 229     struct new_process_request *info;
 230     if (!(info = process->info)) return 0;
 231     process->info = NULL;
 232     reply->start_flags = info->start_flags;
 233     reply->hstdin      = info->hstdin;
 234     reply->hstdout     = info->hstdout;
 235     reply->hstderr     = info->hstderr;
 236     reply->env_ptr     = info->env_ptr;
 237     free( info );
 238     return 1;
 239 }
 240
 241 /* a process has been killed (i.e. its last thread died) */
 242 static void process_killed( struct process *process, int exit_code )
 243 {
 244     assert( !process->thread_list );
 245     process->exit_code = exit_code;
 246     gettimeofday( &process->end_time, NULL );
 247     wake_up( &process->obj, 0 );
 248     free_handles( process );
 249 }
 250
 251 /* free the process handle entries */
 252 static void free_handles( struct process *process )
 253 {
 254     struct handle_entry *entry;
 255     int handle;
 256
 257     if (!(entry = process->entries)) return;
 258     for (handle = 0; handle <= process->handle_last; handle++, entry++)
 259     {
 260         struct object *obj = entry->ptr;
 261         entry->ptr = NULL;
 262         if (obj) release_object( obj );
 263     }
 264     free( process->entries );
 265     process->handle_count = 0;
 266     process->handle_last  = -1;
 267     process->entries = NULL;
 268 }
 269
 270 /* add a thread to a process running threads list */
 271 void add_process_thread( struct process *process, struct thread *thread )
 272 {
 273     thread->proc_next = process->thread_list;
 274     thread->proc_prev = NULL;
 275     if (thread->proc_next) thread->proc_next->proc_prev = thread;
 276     process->thread_list = thread;
 277     if (!process->running_threads++) running_processes++;
 278     grab_object( thread );
 279 }
 280
 281 /* remove a thread from a process running threads list */
 282 void remove_process_thread( struct process *process, struct thread *thread )
 283 {
 284     assert( process->running_threads > 0 );
 285     assert( process->thread_list );
 286
 287     if (thread->proc_next) thread->proc_next->proc_prev = thread->proc_prev;
 288     if (thread->proc_prev) thread->proc_prev->proc_next = thread->proc_next;
 289     else process->thread_list = thread->proc_next;
 290
 291     if (!--process->running_threads)
 292     {
 293         /* we have removed the last running thread, exit the process */
 294         running_processes--;
 295         process_killed( process, thread->exit_code );
 296     }
 297     release_object( thread );
 298 }
 299
 300 /* grow a handle table */
 301 /* return 1 if OK, 0 on error */
 302 static int grow_handle_table( struct process *process )
 303 {
 304     struct handle_entry *new_entries;
 305     int count = process->handle_count;
 306
 307     if (count >= INT_MAX / 2) return 0;
 308     count *= 2;
 309     if (!(new_entries = realloc( process->entries, count * sizeof(struct handle_entry) )))
 310     {
 311         SET_ERROR( ERROR_OUTOFMEMORY );
 312         return 0;
 313     }
 314     process->handle_count = count;
 315     process->entries      = new_entries;
 316     return 1;
 317 }
 318
 319 /* allocate a handle for an object, incrementing its refcount */
 320 /* return the handle, or -1 on error */
 321 int alloc_handle( struct process *process, void *obj, unsigned int access,
 322                   int inherit )
 323 {
 324     struct handle_entry *entry;
 325     int handle;
 326
 327     assert( !(access & RESERVED_ALL) );
 328     if (inherit) access |= RESERVED_INHERIT;
 329
 330     /* find the first free entry */
 331
 332     if (!(entry = process->entries)) return -1;
 333     for (handle = 0; handle <= process->handle_last; handle++, entry++)
 334         if (!entry->ptr) goto found;
 335
 336     if (handle >= process->handle_count)
 337     {
 338         if (!grow_handle_table( process )) return -1;
 339         entry = process->entries + handle;  /* the table may have moved */
 340     }
 341     process->handle_last = handle;
 342
 343  found:
 344     entry->ptr    = grab_object( obj );
 345     entry->access = access;
 346     return handle + 1;  /* avoid handle 0 */
 347 }
 348
 349 /* return an handle entry, or NULL if the handle is invalid */
 350 static struct handle_entry *get_handle( struct process *process, int handle )
 351 {
 352     struct handle_entry *entry;
 353
 354     if (HANDLE_IS_GLOBAL(handle))
 355     {
 356         handle = HANDLE_GLOBAL_TO_LOCAL(handle);
 357         process = &initial_process;
 358     }
 359     handle--;  /* handles start at 1 */
 360     if ((handle < 0) || (handle > process->handle_last)) goto error;
 361     entry = process->entries + handle;
 362     if (!entry->ptr) goto error;
 363     return entry;
 364
 365  error:
 366     SET_ERROR( ERROR_INVALID_HANDLE );
 367     return NULL;
 368 }
 369
 370 /* attempt to shrink a table */
 371 /* return 1 if OK, 0 on error */
 372 static int shrink_handle_table( struct process *process )
 373 {
 374     struct handle_entry *new_entries;
 375     struct handle_entry *entry = process->entries + process->handle_last;
 376     int count = process->handle_count;
 377
 378     while (process->handle_last >= 0)
 379     {
 380         if (entry->ptr) break;
 381         process->handle_last--;
 382         entry--;
 383     }
 384     if (process->handle_last >= count / 4) return 1;  /* no need to shrink */
 385     if (count < MIN_HANDLE_ENTRIES * 2) return 1;  /* too small to shrink */
 386     count /= 2;
 387     if (!(new_entries = realloc( process->entries,
 388                                  count * sizeof(struct handle_entry) )))
 389         return 0;
 390     process->handle_count = count;
 391     process->entries      = new_entries;
 392     return 1;
 393 }
 394
 395 /* copy the handle table of the parent process */
 396 /* return 1 if OK, 0 on error */
 397 static int copy_handle_table( struct process *process, struct process *parent )
 398 {
 399     struct handle_entry *ptr;
 400     int i, count, last;
 401
 402     if (!parent)  /* first process */
 403     {
 404         count = MIN_HANDLE_ENTRIES;
 405         last  = -1;
 406     }
 407     else
 408     {
 409         assert( parent->entries );
 410         count = parent->handle_count;
 411         last  = parent->handle_last;
 412     }
 413
 414     if (!(ptr = mem_alloc( count * sizeof(struct handle_entry)))) return 0;
 415     process->entries      = ptr;
 416     process->handle_count = count;
 417     process->handle_last  = last;
 418
 419     if (last >= 0)
 420     {
 421         memcpy( ptr, parent->entries, (last + 1) * sizeof(struct handle_entry) );
 422         for (i = 0; i <= last; i++, ptr++)
 423         {
 424             if (!ptr->ptr) continue;
 425             if (ptr->access & RESERVED_INHERIT) grab_object( ptr->ptr );
 426             else ptr->ptr = NULL; /* don't inherit this entry */
 427         }
 428     }
 429     /* attempt to shrink the table */
 430     shrink_handle_table( process );
 431     return 1;
 432 }
 433
 434 /* close a handle and decrement the refcount of the associated object */
 435 /* return 1 if OK, 0 on error */
 436 int close_handle( struct process *process, int handle )
 437 {
 438     struct handle_entry *entry;
 439     struct object *obj;
 440
 441     if (HANDLE_IS_GLOBAL(handle))
 442     {
 443         handle = HANDLE_GLOBAL_TO_LOCAL(handle);
 444         process = &initial_process;
 445     }
 446     if (!(entry = get_handle( process, handle ))) return 0;
 447     if (entry->access & RESERVED_CLOSE_PROTECT) return 0;  /* FIXME: error code */
 448     obj = entry->ptr;
 449     entry->ptr = NULL;
 450     if (handle-1 == process->handle_last) shrink_handle_table( process );
 451     release_object( obj );
 452     return 1;
 453 }
 454
 455 /* retrieve the object corresponding to a handle, incrementing its refcount */
 456 struct object *get_handle_obj( struct process *process, int handle,
 457                                unsigned int access, const struct object_ops *ops )
 458 {
 459     struct handle_entry *entry;
 460     struct object *obj;
 461
 462     switch( handle )
 463     {
 464     case 0xfffffffe:  /* current thread pseudo-handle */
 465         obj = &current->obj;
 466         break;
 467     case 0x7fffffff:  /* current process pseudo-handle */
 468         obj = (struct object *)current->process;
 469         break;
 470     default:
 471         if (!(entry = get_handle( process, handle ))) return NULL;
 472         if ((entry->access & access) != access)
 473         {
 474             SET_ERROR( ERROR_ACCESS_DENIED );
 475             return NULL;
 476         }
 477         obj = entry->ptr;
 478         break;
 479     }
 480     if (ops && (obj->ops != ops))
 481     {
 482         SET_ERROR( ERROR_INVALID_HANDLE );  /* not the right type */
 483         return NULL;
 484     }
 485     return grab_object( obj );
 486 }
 487
 488 /* get/set the handle reserved flags */
 489 /* return the new flags (or -1 on error) */
 490 int set_handle_info( struct process *process, int handle, int mask, int flags )
 491 {
 492     struct handle_entry *entry;
 493
 494     if (!(entry = get_handle( process, handle ))) return -1;
 495     mask  = (mask << RESERVED_SHIFT) & RESERVED_ALL;
 496     flags = (flags << RESERVED_SHIFT) & mask;
 497     entry->access = (entry->access & ~mask) | flags;
 498     return (entry->access & RESERVED_ALL) >> RESERVED_SHIFT;
 499 }
 500
 501 /* duplicate a handle */
 502 int duplicate_handle( struct process *src, int src_handle, struct process *dst,
 503                       unsigned int access, int inherit, int options )
 504 {
 505     int res;
 506     struct handle_entry *entry = get_handle( src, src_handle );
 507     if (!entry) return -1;
 508
 509     if (options & DUP_HANDLE_SAME_ACCESS) access = entry->access;
 510     if (options & DUP_HANDLE_MAKE_GLOBAL) dst = &initial_process;
 511     access &= ~RESERVED_ALL;
 512     res = alloc_handle( dst, entry->ptr, access, inherit );
 513     if (options & DUP_HANDLE_MAKE_GLOBAL) res = HANDLE_LOCAL_TO_GLOBAL(res);
 514     return res;
 515 }
 516
 517 /* open a new handle to an existing object */
 518 int open_object( const char *name, const struct object_ops *ops,
 519                  unsigned int access, int inherit )
 520 {
 521     struct object *obj = find_object( name );
 522     if (!obj)
 523     {
 524         SET_ERROR( ERROR_FILE_NOT_FOUND );
 525         return -1;
 526     }
 527     if (ops && obj->ops != ops)
 528     {
 529         release_object( obj );
 530         SET_ERROR( ERROR_INVALID_HANDLE );  /* FIXME: not the right type */
 531         return -1;
 532     }
 533     return alloc_handle( current->process, obj, access, inherit );
 534 }
 535
 536 /* dump a handle table on stdout */
 537 void dump_handles( struct process *process )
 538 {
 539     struct handle_entry *entry;
 540     int i;
 541
 542     if (!process->entries) return;
 543     entry = process->entries;
 544     for (i = 0; i <= process->handle_last; i++, entry++)
 545     {
 546         if (!entry->ptr) continue;
 547         printf( "%5d: %p %08x ", i + 1, entry->ptr, entry->access );
 548         entry->ptr->ops->dump( entry->ptr, 0 );
 549     }
 550 }
 551
 552 /* kill a process on the spot */
 553 void kill_process( struct process *process, int exit_code )
 554 {
 555     while (process->thread_list)
 556         kill_thread( process->thread_list, exit_code );
 557 }
 558
 559 /* get all information about a process */
 560 void get_process_info( struct process *process,
 561                        struct get_process_info_reply *reply )
 562 {
 563     reply->pid              = process;
 564     reply->exit_code        = process->exit_code;
 565     reply->priority         = process->priority;
 566     reply->process_affinity = process->affinity;
 567     reply->system_affinity  = 1;
 568 }
 569
 570 /* set all information about a process */
 571 void set_process_info( struct process *process,
 572                        struct set_process_info_request *req )
 573 {
 574     if (req->mask & SET_PROCESS_INFO_PRIORITY)
 575         process->priority = req->priority;
 576     if (req->mask & SET_PROCESS_INFO_AFFINITY)
 577     {
 578         if (req->affinity != 1) SET_ERROR( ERROR_INVALID_PARAMETER );
 579         else process->affinity = req->affinity;
 580     }
 581 }
 582
 583 /* allocate a console for this process */
 584 int alloc_console( struct process *process )
 585 {
 586     struct object *obj[2];
 587     if (process->console_in || process->console_out)
 588     {
 589         SET_ERROR( ERROR_ACCESS_DENIED );
 590         return 0;
 591     }
 592     if (!create_console( -1, obj )) return 0;
 593     process->console_in  = obj[0];
 594     process->console_out = obj[1];
 595     return 1;
 596 }
 597
 598 /* free the console for this process */
 599 int free_console( struct process *process )
 600 {
 601     if (process->console_in) release_object( process->console_in );
 602     if (process->console_out) release_object( process->console_out );
 603     process->console_in = process->console_out = NULL;
 604     return 1;
 605 }
 606
 607 /* get the process console */
 608 struct object *get_console( struct process *process, int output )
 609 {
 610     struct object *obj;
 611     if (!(obj = output ? process->console_out : process->console_in))
 612         return NULL;
 613     return grab_object( obj );
 614 }
 615
 616 /* take a snapshot of currently running processes */
 617 struct process_snapshot *process_snap( int *count )
 618 {
 619     struct process_snapshot *snapshot, *ptr;
 620     struct process *process;
 621     if (!running_processes) return NULL;
 622     if (!(snapshot = mem_alloc( sizeof(*snapshot) * running_processes )))
 623         return NULL;
 624     ptr = snapshot;
 625     for (process = first_process; process; process = process->next)
 626     {
 627         if (!process->running_threads) continue;
 628         ptr->process  = process;
 629         ptr->threads  = process->running_threads;
 630         ptr->priority = process->priority;
 631         grab_object( process );
 632         ptr++;
 633     }
 634     *count = running_processes;
 635     return snapshot;
 636 }