1# Reply server mig-output massager 2# 3# Copyright (C) 1995-2014 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 3, 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, see <http://www.gnu.org/licenses/>. 19# 20# This awk script hacks the output of mig-generated reply server code 21# so that it allows replies with just the error-code in them (as this is 22# how mig returns errors). 23# 24# It is highly, highly, dependent on the exact format of mig output. Ick. 25# 26 27BEGIN { parse_phase = 0; } 28 29/^}/ { parse_phase = 0; } 30 31parse_phase == 0 && /^mig_internal void _X[a-zA-Z0-9_]*_reply/ { 32 # The start of a mig server routine. Reset everything. Note that we only 33 # mess with rpcs that have the suffix `_reply'. 34 num_args = 0; 35 num_checks = 0; 36 parse_phase = 1; 37 print; next; 38} 39 40parse_phase == 1 && /^[\t ]*typedef struct/ { 41 # The first structure in the server routine should describe the arguments 42 parse_phase = 2; 43 print; next; 44} 45 46parse_phase == 2 { 47 # The message header field in the args structure, which skip. 48 parse_phase = 3; 49 print; next; 50} 51 52parse_phase == 3 && /}/ { 53 # The args structure is over. 54 if (num_args > 1) 55 parse_phase = 5; 56 else 57 # There's no extra args that could screw up the normal mechanism for 58 # error returns, so we don't have to insert any new code. 59 parse_phase = 0; 60 print; next; 61} 62 63parse_phase == 3 { 64 # The type field for an argument. 65 arg_type_code_name[num_args] = $2; 66 sub (/;$/, "", arg_type_code_name[num_args]) # Get rid of the semi-colon 67 parse_phase = 4; 68 print; next; 69} 70 71parse_phase == 4 { 72 # The value field for an argument. 73 arg_name[num_args] = $2; 74 sub (/;$/, "", arg_name[num_args]) # Get rid of the semi-colon 75 arg_type[num_args] = $1; 76 num_args++; 77 parse_phase = 3; 78 print; next; 79} 80 81parse_phase == 5 && /^[ \t]*(auto|static) const mach_msg_type_t/ { 82 # The type check structure for an argument. 83 arg_check_name[num_checks] = $4; 84 num_checks++; 85 print; next; 86} 87 88parse_phase == 5 && /^[ \t]*mig_external kern_return_t/ { 89 # The declaration of the user server function for this rpc. 90 user_function_name = $3; 91 print; next; 92} 93 94parse_phase == 5 && /^#if[ \t]TypeCheck/ { 95 # The first args type checking statement; we need to insert our chunk of 96 # code that bypasses all the type checks if this is an error return, after 97 # which we're done until we get to the next function. Handily, the size 98 # of mig's Reply structure is also the size of the alternate Request 99 # structure that we want to check for. 100 print "\tif (In0P->Head.msgh_size == sizeof (Reply)"; 101 print "\t && ! (In0P->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)"; 102 print "\t && ! BAD_TYPECHECK(&In0P->" arg_type_code_name[0] ", &" arg_check_name[0] ")"; 103 print "\t && In0P->" arg_name[0] " != 0)"; 104 print "\t /* Error return, only the error code argument is passed. */"; 105 print "\t {"; 106 # Force the function into a type that only takes the first two args, via 107 # the temp variable SFUN (is there another way to correctly do this cast?). 108 # This is possibly bogus, but easier than supplying bogus values for all 109 # the other args (we can't just pass 0 for them, as they might not be scalar). 110 printf ("\t kern_return_t (*sfun)(mach_port_t"); 111 for (i = 0; i < num_args; i++) 112 printf (", %s", arg_type[i]); 113 printf (") = %s;\n", user_function_name); 114 print "\t OutP->RetCode = (*(kern_return_t (*)(mach_port_t, kern_return_t))sfun) (In0P->Head.msgh_request_port, In0P->" arg_name[0] ");"; 115 print "\t return;"; 116 print "\t }"; 117 print ""; 118 parse_phase = 0; 119 print; next; 120} 121 122{ print; } 123