1# Reply server mig-output massager
2#
3#   Copyright 1995, 1996, 1999 Free Software Foundation, Inc.
4#
5#   Written by Miles Bader <miles@gnu.ai.mit.edu>
6#
7#   This program is free software; you can redistribute it and/or
8#   modify it under the terms of the GNU General Public License as
9#   published by the Free Software Foundation; either version 2, or (at
10#   your option) any later version.
11#
12#   This program is distributed in the hope that it will be useful, but
13#   WITHOUT ANY WARRANTY; without even the implied warranty of
14#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15#   General Public License for more details.
16#
17#   You should have received a copy of the GNU General Public License
18#   along with this program; if not, write to the Free Software
19#   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20#
21# This awk script hacks the output of mig-generated reply server code
22# so that it allows replies with just the error-code in them (as this is
23# how mig returns errors).
24#
25# It is highly, highly, dependent on the exact format of mig output.  Ick.
26#
27
28BEGIN { parse_phase = 0; }
29
30/^}/ { parse_phase = 0; }
31
32parse_phase == 0 && /^mig_internal void _X[a-zA-Z0-9_]*_reply/ {
33  # The start of a mig server routine.  Reset everything.  Note that we only
34  # mess with rpcs that have the suffix `_reply'.
35  num_args = 0;
36  num_checks = 0;
37  parse_phase = 1;
38  print; next;
39}
40
41parse_phase == 1 && /^[\t ]*typedef struct/ {
42  # The first structure in the server routine should describe the arguments
43  parse_phase = 2;
44  print; next;
45}
46
47parse_phase == 2 {
48  # The message header field in the args structure, which skip.
49  parse_phase = 3;
50  print; next;
51}
52
53parse_phase == 3 && /}/ {
54  # The args structure is over.
55  if (num_args > 1)
56    parse_phase = 5;
57  else
58    # There's no extra args that could screw up the normal mechanism for
59    # error returns, so we don't have to insert any new code.
60    parse_phase = 0;
61  print; next;
62}
63
64parse_phase == 3 {
65  # The type field for an argument.
66  arg_type_code_name[num_args] = $2;
67  sub (/;$/, "", arg_type_code_name[num_args]) # Get rid of the semi-colon
68  parse_phase = 4;
69  print; next;
70}
71
72parse_phase == 4 {
73  # The value field for an argument.
74  arg_name[num_args] = $2;
75  sub (/;$/, "", arg_name[num_args]) # Get rid of the semi-colon
76  arg_type[num_args] = $1;
77  num_args++;
78  parse_phase = 3;
79  print; next;
80}
81
82parse_phase == 5 && /^[ \t]*static const mach_msg_type_t/ {
83  # The type check structure for an argument.
84  arg_check_name[num_checks] = $4;
85  num_checks++;
86  print; next;
87}
88
89parse_phase == 5 && /^[ \t]*mig_external kern_return_t/ {
90  # The declaration of the user server function for this rpc.
91  user_function_name = $3;
92  print; next;
93}
94
95parse_phase == 5 && /^#if[ \t]TypeCheck/ {
96  # The first args type checking statement; we need to insert our chunk of
97  # code that bypasses all the type checks if this is an error return, after
98  # which we're done until we get to the next function.  Handily, the size
99  # of mig's Reply structure is also the size of the alternate Request 
100  # structure that we want to check for.
101  print "\tif (In0P->Head.msgh_size == sizeof (Reply)";
102  print "\t    && ! (In0P->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)";
103  print "\t    && *(int *)&In0P->" arg_type_code_name[0] " == *(int *)&" arg_check_name[0];
104  print "\t    && In0P->" arg_name[0] " != 0)";
105  print "\t  /* Error return, only the error code argument is passed.  */";
106  print "\t  {";
107  # Force the function into a type that only takes the first two args, via
108  # the temp variable SFUN (is there another way to correctly do this cast?).
109  # This is possibly bogus, but easier than supplying bogus values for all
110  # the other args (we can't just pass 0 for them, as they might not be scalar).
111  printf ("\t    kern_return_t (*sfun)(mach_port_t");
112  for (i = 0; i < num_args; i++)
113    printf (", %s", arg_type[i]);
114  printf (") = %s;\n", user_function_name);
115  print "\t    OutP->RetCode = (*(kern_return_t (*)(mach_port_t, kern_return_t))sfun) (In0P->Head.msgh_request_port, In0P->" arg_name[0] ");";
116  print "\t    return;";
117  print "\t  }";
118  print "";
119  parse_phase = 0;
120  print; next;
121}
122
123{ print; }
124