Sweden-Number/server/process.c

485 lines
14 KiB
C

/*
* Server-side process management
*
* Copyright (C) 1998 Alexandre Julliard
*/
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <unistd.h>
#include "winerror.h"
#include "winbase.h"
#include "winnt.h"
#include "server.h"
#include "server/thread.h"
/* reserved handle access rights */
#define RESERVED_SHIFT 25
#define RESERVED_INHERIT (HANDLE_FLAG_INHERIT << RESERVED_SHIFT)
#define RESERVED_CLOSE_PROTECT (HANDLE_FLAG_PROTECT_FROM_CLOSE << RESERVED_SHIFT)
#define RESERVED_ALL (RESERVED_INHERIT | RESERVED_CLOSE_PROTECT)
struct handle_entry
{
struct object *ptr;
unsigned int access;
};
/* process structure; not much for now... */
struct process
{
struct object obj; /* object header */
struct process *next; /* system-wide process list */
struct process *prev;
struct thread *thread_list; /* head of the thread list */
struct handle_entry *entries; /* handle entry table */
int handle_count; /* nb of allocated handle entries */
int handle_last; /* last used handle entry */
int exit_code; /* process exit code */
int running_threads; /* number of threads running in this process */
struct timeval start_time; /* absolute time at process start */
struct timeval end_time; /* absolute time at process end */
};
static struct process *first_process;
#define MIN_HANDLE_ENTRIES 32
/* process operations */
static void dump_process( struct object *obj, int verbose );
static int process_signaled( struct object *obj, struct thread *thread );
static int process_satisfied( struct object *obj, struct thread *thread );
static void destroy_process( struct object *obj );
static void free_handles( struct process *process );
static int copy_handle_table( struct process *process, struct process *parent );
static const struct object_ops process_ops =
{
dump_process,
process_signaled,
process_satisfied,
destroy_process
};
/* create a new process */
struct process *create_process(void)
{
struct process *process;
if (!(process = mem_alloc( sizeof(*process) ))) return NULL;
if (!copy_handle_table( process, current ? current->process : NULL ))
{
free( process );
return NULL;
}
init_object( &process->obj, &process_ops, NULL );
process->next = first_process;
process->prev = NULL;
process->thread_list = NULL;
process->exit_code = 0x103; /* STILL_ACTIVE */
process->running_threads = 0;
if (first_process) first_process->prev = process;
first_process = process;
gettimeofday( &process->start_time, NULL );
/* alloc a handle for the process itself */
alloc_handle( process, process, PROCESS_ALL_ACCESS, 0 );
return process;
}
/* destroy a process when its refcount is 0 */
static void destroy_process( struct object *obj )
{
struct process *process = (struct process *)obj;
assert( obj->ops == &process_ops );
/* we can't have a thread remaining */
assert( !process->thread_list );
if (process->next) process->next->prev = process->prev;
if (process->prev) process->prev->next = process->next;
else first_process = process->next;
free_handles( process );
if (debug_level) memset( process, 0xbb, sizeof(process) ); /* catch errors */
free( process );
}
/* dump a process on stdout for debugging purposes */
static void dump_process( struct object *obj, int verbose )
{
struct process *process = (struct process *)obj;
assert( obj->ops == &process_ops );
printf( "Process next=%p prev=%p\n", process->next, process->prev );
}
static int process_signaled( struct object *obj, struct thread *thread )
{
struct process *process = (struct process *)obj;
return (process->running_threads > 0);
}
static int process_satisfied( struct object *obj, struct thread *thread )
{
return 0;
}
/* get a process from an id (and increment the refcount) */
struct process *get_process_from_id( void *id )
{
struct process *p = first_process;
while (p && (p != id)) p = p->next;
if (p) grab_object( p );
else SET_ERROR( ERROR_INVALID_PARAMETER );
return p;
}
/* get a process from a handle (and increment the refcount) */
struct process *get_process_from_handle( int handle, unsigned int access )
{
return (struct process *)get_handle_obj( current->process, handle,
access, &process_ops );
}
/* a process has been killed (i.e. its last thread died) */
static void process_killed( struct process *process, int exit_code )
{
assert( !process->thread_list );
process->exit_code = exit_code;
gettimeofday( &process->end_time, NULL );
wake_up( &process->obj, 0 );
free_handles( process );
}
/* free the process handle entries */
static void free_handles( struct process *process )
{
struct handle_entry *entry;
int handle;
if (!(entry = process->entries)) return;
for (handle = 0; handle <= process->handle_last; handle++, entry++)
{
struct object *obj = entry->ptr;
entry->ptr = NULL;
if (obj) release_object( obj );
}
free( process->entries );
process->handle_count = 0;
process->handle_last = -1;
process->entries = NULL;
}
/* add a thread to a process running threads list */
void add_process_thread( struct process *process, struct thread *thread )
{
thread->proc_next = process->thread_list;
thread->proc_prev = NULL;
if (thread->proc_next) thread->proc_next->proc_prev = thread;
process->thread_list = thread;
process->running_threads++;
grab_object( thread );
}
/* remove a thread from a process running threads list */
void remove_process_thread( struct process *process, struct thread *thread )
{
assert( process->running_threads > 0 );
assert( process->thread_list );
if (thread->proc_next) thread->proc_next->proc_prev = thread->proc_prev;
if (thread->proc_prev) thread->proc_prev->proc_next = thread->proc_next;
else process->thread_list = thread->proc_next;
if (!--process->running_threads)
{
/* we have removed the last running thread, exit the process */
process_killed( process, thread->exit_code );
}
release_object( thread );
}
/* grow a handle table */
/* return 1 if OK, 0 on error */
static int grow_handle_table( struct process *process )
{
struct handle_entry *new_entries;
int count = process->handle_count;
if (count >= INT_MAX / 2) return 0;
count *= 2;
if (!(new_entries = realloc( process->entries, count * sizeof(struct handle_entry) )))
{
SET_ERROR( ERROR_OUTOFMEMORY );
return 0;
}
process->handle_count = count;
process->entries = new_entries;
return 1;
}
/* allocate a handle for an object, incrementing its refcount */
/* return the handle, or -1 on error */
int alloc_handle( struct process *process, void *obj, unsigned int access,
int inherit )
{
struct handle_entry *entry;
int handle;
assert( !(access & RESERVED_ALL) );
if (inherit) access |= RESERVED_INHERIT;
/* find the first free entry */
if (!(entry = process->entries)) return -1;
for (handle = 0; handle <= process->handle_last; handle++, entry++)
if (!entry->ptr) goto found;
if (handle >= process->handle_count)
{
if (!grow_handle_table( process )) return -1;
entry = process->entries + handle; /* the table may have moved */
}
process->handle_last = handle;
found:
entry->ptr = grab_object( obj );
entry->access = access;
return handle + 1; /* avoid handle 0 */
}
/* allocate a specific handle for an object, incrementing its refcount */
static int alloc_specific_handle( struct process *process, void *obj, int handle,
unsigned int access, int inherit )
{
struct handle_entry *entry;
struct object *old;
if (handle == -1) return alloc_handle( process, obj, access, inherit );
assert( !(access & RESERVED_ALL) );
if (inherit) access |= RESERVED_INHERIT;
handle--; /* handles start at 1 */
if ((handle < 0) || (handle > process->handle_last))
{
SET_ERROR( ERROR_INVALID_HANDLE );
return -1;
}
entry = process->entries + handle;
old = entry->ptr;
entry->ptr = grab_object( obj );
entry->access = access;
if (old) release_object( old );
return handle + 1;
}
/* return an handle entry, or NULL if the handle is invalid */
static struct handle_entry *get_handle( struct process *process, int handle )
{
struct handle_entry *entry;
handle--; /* handles start at 1 */
if ((handle < 0) || (handle > process->handle_last)) goto error;
entry = process->entries + handle;
if (!entry->ptr) goto error;
return entry;
error:
SET_ERROR( ERROR_INVALID_HANDLE );
return NULL;
}
/* attempt to shrink a table */
/* return 1 if OK, 0 on error */
static int shrink_handle_table( struct process *process )
{
struct handle_entry *new_entries;
struct handle_entry *entry = process->entries + process->handle_last;
int count = process->handle_count;
while (process->handle_last >= 0)
{
if (entry->ptr) break;
process->handle_last--;
entry--;
}
if (process->handle_last >= count / 4) return 1; /* no need to shrink */
if (count < MIN_HANDLE_ENTRIES * 2) return 1; /* too small to shrink */
count /= 2;
if (!(new_entries = realloc( process->entries,
count * sizeof(struct handle_entry) )))
return 0;
process->handle_count = count;
process->entries = new_entries;
return 1;
}
/* copy the handle table of the parent process */
/* return 1 if OK, 0 on error */
static int copy_handle_table( struct process *process, struct process *parent )
{
struct handle_entry *ptr;
int i, count, last;
if (!parent) /* first process */
{
count = MIN_HANDLE_ENTRIES;
last = -1;
}
else
{
assert( parent->entries );
count = parent->handle_count;
last = parent->handle_last;
}
if (!(ptr = mem_alloc( count * sizeof(struct handle_entry)))) return 0;
process->entries = ptr;
process->handle_count = count;
process->handle_last = last;
if (last >= 0)
{
memcpy( ptr, parent->entries, (last + 1) * sizeof(struct handle_entry) );
for (i = 0; i <= last; i++, ptr++)
{
if (!ptr->ptr) continue;
if (ptr->access & RESERVED_INHERIT) grab_object( ptr->ptr );
else ptr->ptr = NULL; /* don't inherit this entry */
}
}
/* attempt to shrink the table */
shrink_handle_table( process );
return 1;
}
/* close a handle and decrement the refcount of the associated object */
/* return 1 if OK, 0 on error */
int close_handle( struct process *process, int handle )
{
struct handle_entry *entry;
struct object *obj;
if (!(entry = get_handle( process, handle ))) return 0;
if (entry->access & RESERVED_CLOSE_PROTECT) return 0; /* FIXME: error code */
obj = entry->ptr;
entry->ptr = NULL;
if (handle-1 == process->handle_last) shrink_handle_table( process );
release_object( obj );
return 1;
}
/* retrieve the object corresponding to a handle, incrementing its refcount */
struct object *get_handle_obj( struct process *process, int handle,
unsigned int access, const struct object_ops *ops )
{
struct handle_entry *entry;
struct object *obj;
switch( handle )
{
case 0xfffffffe: /* current thread pseudo-handle */
obj = &current->obj;
break;
case 0x7fffffff: /* current process pseudo-handle */
obj = (struct object *)current->process;
break;
default:
if (!(entry = get_handle( process, handle ))) return NULL;
if ((entry->access & access) != access)
{
SET_ERROR( ERROR_ACCESS_DENIED );
return NULL;
}
obj = entry->ptr;
break;
}
if (ops && (obj->ops != ops))
{
SET_ERROR( ERROR_INVALID_HANDLE ); /* not the right type */
return NULL;
}
return grab_object( obj );
}
/* get/set the handle reserved flags */
/* return the new flags (or -1 on error) */
int set_handle_info( struct process *process, int handle, int mask, int flags )
{
struct handle_entry *entry;
if (!(entry = get_handle( process, handle ))) return -1;
mask = (mask << RESERVED_SHIFT) & RESERVED_ALL;
flags = (flags << RESERVED_SHIFT) & mask;
entry->access = (entry->access & ~mask) | flags;
return (entry->access & RESERVED_ALL) >> RESERVED_SHIFT;
}
/* duplicate a handle */
int duplicate_handle( struct process *src, int src_handle, struct process *dst,
int dst_handle, unsigned int access, int inherit, int options )
{
struct handle_entry *entry = get_handle( src, src_handle );
if (!entry) return -1;
if (options & DUPLICATE_SAME_ACCESS) access = entry->access;
access &= ~RESERVED_ALL;
return alloc_specific_handle( dst, entry->ptr, dst_handle, access, inherit );
}
/* open a new handle to an existing object */
int open_object( const char *name, const struct object_ops *ops,
unsigned int access, int inherit )
{
struct object *obj = find_object( name );
if (!obj) return -1; /* FIXME: set error code */
if (ops && obj->ops != ops)
{
release_object( obj );
return -1; /* FIXME: set error code */
}
return alloc_handle( current->process, obj, access, inherit );
}
/* dump a handle table on stdout */
void dump_handles( struct process *process )
{
struct handle_entry *entry;
int i;
if (!process->entries) return;
entry = process->entries;
for (i = 0; i <= process->handle_last; i++, entry++)
{
if (!entry->ptr) continue;
printf( "%5d: %p %08x ", i + 1, entry->ptr, entry->access );
entry->ptr->ops->dump( entry->ptr, 0 );
}
}
/* kill a process on the spot */
void kill_process( struct process *process, int exit_code )
{
while (process->thread_list)
kill_thread( process->thread_list, exit_code );
}
/* get all information about a process */
void get_process_info( struct process *process,
struct get_process_info_reply *reply )
{
reply->pid = process;
reply->exit_code = process->exit_code;
}