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 "winerror.h"
  14 #include "winnt.h"
  15 #include "tlhelp32.h"
  16
  17 #include "handle.h"
  18 #include "process.h"
  19 #include "thread.h"
  20 #include "request.h"
  21
  22
  23 struct snapshot
  24 {
  25     struct object             obj;           /* object header */
  26     struct process_snapshot  *process;       /* processes snapshot */
  27     int                       process_count; /* count of processes */
  28     int                       process_pos;   /* current position in proc snapshot */
  29 };
  30
  31 static void snapshot_dump( struct object *obj, int verbose );
  32 static void snapshot_destroy( struct object *obj );
  33
  34 static const struct object_ops snapshot_ops =
  35 {
  36     sizeof(struct snapshot),
  37     snapshot_dump,
  38     no_add_queue,
  39     NULL,  /* should never get called */
  40     NULL,  /* should never get called */
  41     NULL,  /* should never get called */
  42     no_read_fd,
  43     no_write_fd,
  44     no_flush,
  45     no_get_file_info,
  46     snapshot_destroy
  47 };
  48
  49
  50 /* create a new snapshot */
  51 static struct snapshot *create_snapshot( int flags )
  52 {
  53     struct snapshot *snapshot;
  54
  55     if ((snapshot = alloc_object( &snapshot_ops )))
  56     {
  57         if (flags & TH32CS_SNAPPROCESS)
  58             snapshot->process = process_snap( &snapshot->process_count );
  59         else
  60             snapshot->process_count = 0;
  61         snapshot->process_pos = 0;
  62     }
  63     return snapshot;
  64 }
  65
  66 /* get the next process in the snapshot */
  67 static int snapshot_next_process( struct snapshot *snapshot, struct next_process_request *req )
  68 {
  69     struct process_snapshot *ptr;
  70
  71     if (!snapshot->process_count)
  72     {
  73         set_error( ERROR_INVALID_PARAMETER );  /* FIXME */
  74         return 0;
  75     }
  76     if (req->reset) snapshot->process_pos = 0;
  77     else if (snapshot->process_pos >= snapshot->process_count)
  78     {
  79         set_error( ERROR_NO_MORE_FILES );
  80         return 0;
  81     }
  82     ptr = &snapshot->process[snapshot->process_pos++];
  83     req->pid      = ptr->process;
  84     req->threads  = ptr->threads;
  85     req->priority = ptr->priority;
  86     return 1;
  87 }
  88
  89 static void snapshot_dump( struct object *obj, int verbose )
  90 {
  91     struct snapshot *snapshot = (struct snapshot *)obj;
  92     assert( obj->ops == &snapshot_ops );
  93     fprintf( stderr, "Snapshot: %d processes\n",
  94              snapshot->process_count );
  95 }
  96
  97 static void snapshot_destroy( struct object *obj )
  98 {
  99     int i;
 100     struct snapshot *snapshot = (struct snapshot *)obj;
 101     assert( obj->ops == &snapshot_ops );
 102     if (snapshot->process_count)
 103     {
 104         for (i = 0; i < snapshot->process_count; i++)
 105             release_object( snapshot->process[i].process );
 106         free( snapshot->process );
 107     }
 108 }
 109
 110 /* create a snapshot */
 111 DECL_HANDLER(create_snapshot)
 112 {
 113     struct snapshot *snapshot;
 114
 115     req->handle = -1;
 116     if ((snapshot = create_snapshot( req->flags )))
 117     {
 118         req->handle = alloc_handle( current->process, snapshot, 0, req->inherit );
 119         release_object( snapshot );
 120     }
 121 }
 122
 123 /* get the next process from a snapshot */
 124 DECL_HANDLER(next_process)
 125 {
 126     struct snapshot *snapshot;
 127
 128     if ((snapshot = (struct snapshot *)get_handle_obj( current->process, req->handle,
 129                                                        0, &snapshot_ops )))
 130     {
 131         snapshot_next_process( snapshot, req );
 132         release_object( snapshot );
 133     }
 134 }