server/snapshot.c

   1 /*
   2  * Server-side snapshots
   3  *
   4  * Copyright (C) 1999 Alexandre Julliard
   5  *
   6  * FIXME: only process snapshots implemented for now
   7  */
   8
   9 #include <assert.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12
  13 #include "winnt.h"
  14 #include "tlhelp32.h"
  15
  16 #include "handle.h"
  17 #include "process.h"
  18 #include "thread.h"
  19 #include "request.h"
  20
  21
  22 struct snapshot
  23 {
  24     struct object             obj;           /* object header */
  25     struct process_snapshot  *process;       /* processes snapshot */
  26     int                       process_count; /* count of processes */
  27     int                       process_pos;   /* current position in proc snapshot */
  28 };
  29
  30 static void snapshot_dump( struct object *obj, int verbose );
  31 static void snapshot_destroy( struct object *obj );
  32
  33 static const struct object_ops snapshot_ops =
  34 {
  35     sizeof(struct snapshot),      /* size */
  36     snapshot_dump,                /* dump */
  37     no_add_queue,                 /* add_queue */
  38     NULL,                         /* remove_queue */
  39     NULL,                         /* signaled */
  40     NULL,                         /* satisfied */
  41     NULL,                         /* get_poll_events */
  42     NULL,                         /* poll_event */
  43     no_read_fd,                   /* get_read_fd */
  44     no_write_fd,                  /* get_write_fd */
  45     no_flush,                     /* flush */
  46     no_get_file_info,             /* get_file_info */
  47     snapshot_destroy              /* destroy */
  48 };
  49
  50
  51 /* create a new snapshot */
  52 static struct snapshot *create_snapshot( int flags )
  53 {
  54     struct snapshot *snapshot;
  55
  56     if ((snapshot = alloc_object( &snapshot_ops, -1 )))
  57     {
  58         if (flags & TH32CS_SNAPPROCESS)
  59             snapshot->process = process_snap( &snapshot->process_count );
  60         else
  61             snapshot->process_count = 0;
  62         snapshot->process_pos = 0;
  63     }
  64     return snapshot;
  65 }
  66
  67 /* get the next process in the snapshot */
  68 static int snapshot_next_process( struct snapshot *snapshot, struct next_process_request *req )
  69 {
  70     struct process_snapshot *ptr;
  71
  72     if (!snapshot->process_count)
  73     {
  74         set_error( STATUS_INVALID_PARAMETER );  /* FIXME */
  75         return 0;
  76     }
  77     if (req->reset) snapshot->process_pos = 0;
  78     else if (snapshot->process_pos >= snapshot->process_count)
  79     {
  80         set_error( STATUS_NO_MORE_FILES );
  81         return 0;
  82     }
  83     ptr = &snapshot->process[snapshot->process_pos++];
  84     req->pid      = ptr->process;
  85     req->threads  = ptr->threads;
  86     req->priority = ptr->priority;
  87     return 1;
  88 }
  89
  90 static void snapshot_dump( struct object *obj, int verbose )
  91 {
  92     struct snapshot *snapshot = (struct snapshot *)obj;
  93     assert( obj->ops == &snapshot_ops );
  94     fprintf( stderr, "Snapshot: %d processes\n",
  95              snapshot->process_count );
  96 }
  97
  98 static void snapshot_destroy( struct object *obj )
  99 {
 100     int i;
 101     struct snapshot *snapshot = (struct snapshot *)obj;
 102     assert( obj->ops == &snapshot_ops );
 103     if (snapshot->process_count)
 104     {
 105         for (i = 0; i < snapshot->process_count; i++)
 106             release_object( snapshot->process[i].process );
 107         free( snapshot->process );
 108     }
 109 }
 110
 111 /* create a snapshot */
 112 DECL_HANDLER(create_snapshot)
 113 {
 114     struct snapshot *snapshot;
 115
 116     req->handle = -1;
 117     if ((snapshot = create_snapshot( req->flags )))
 118     {
 119         req->handle = alloc_handle( current->process, snapshot, 0, req->inherit );
 120         release_object( snapshot );
 121     }
 122 }
 123
 124 /* get the next process from a snapshot */
 125 DECL_HANDLER(next_process)
 126 {
 127     struct snapshot *snapshot;
 128
 129     if ((snapshot = (struct snapshot *)get_handle_obj( current->process, req->handle,
 130                                                        0, &snapshot_ops )))
 131     {
 132         snapshot_next_process( snapshot, req );
 133         release_object( snapshot );
 134     }
 135 }