1#!/bin/awk -f
2# Check a list of symbols against the master definition
3# (official) list.  Arguments:
4#
5# awk -f checksym.awk official-def list-to-check
6#
7# Output is a file in the current directory called 'symbols.new',
8# the value of the awk variable "of" (which can be changed on the
9# command line if required.)  stdout holds error messages.  Error
10# code indicates success or failure.
11#
12# NOTE: this is a pure, old fashioned, awk script.  It will
13# work with any awk
14
15BEGIN{
16   err=0
17   master=""        # master file
18   official[1] = "" # defined symbols from master file
19   symbol[1] = ""   # defined symbols from png.h
20   removed[1] = ""  # removed symbols from png.h
21   lasto = 0        # last ordinal value from png.h
22   mastero = 0      # highest ordinal in master file
23   symbolo = 0      # highest ordinal in png.h
24   missing = "error"# log an error on missing symbols
25   of="symbols.new" # default to a fixed name
26}
27
28# Read existing definitions from the master file (the first
29# file on the command line.)  This must be a def file and it
30# has definition lines (others are ignored) of the form:
31#
32#   symbol @ordinal
33#
34master == "" {
35   master = FILENAME
36}
37FILENAME==master && NF==2 && $2~/^@/ && $1!~/^;/ {
38   o=0+substr($2,2)
39   if (o > 0) {
40      if (official[o] == "") {
41         official[o] = $1
42         if (o > mastero) mastero = o
43         next
44      } else
45         print master ": duplicated symbol:", official[o] ":", $0
46   } else
47      print master ": bad export line format:", $0
48   err = 1
49}
50FILENAME==master && $1==";missing" && NF==2{
51   # This allows the master file to control how missing symbols
52   # are handled; symbols that aren't in either the master or
53   # the new file.  Valid values are 'ignore', 'warning' and
54   # 'error'
55   missing = $2
56}
57FILENAME==master {
58   next
59}
60
61# Read new definitions, these are free form but the lines must
62# just be symbol definitions.  Lines will be commented out for
63# 'removed' symbols, introduced in png.h using PNG_REMOVED rather
64# than PNG_EXPORT.  Use symbols.dfn or pngwin.dfn to generate the
65# input file.
66#
67#  symbol @ordinal   # two fields, exported symbol
68#  ; symbol @ordinal # three fields, removed symbol
69#  ; @ordinal        # two fields, the last ordinal
70NF==2 && $1 == ";" && $2 ~ /^@[1-9][0-9]*$/ { # last ordinal
71   o=0+substr($2,2)
72   if (lasto == 0 || lasto == o)
73      lasto=o
74   else {
75      print "png.h: duplicated last ordinal:", lasto, o
76      err = 1
77   }
78   next
79}
80NF==3 && $1 == ";" && $3 ~ /^@[1-9][0-9]*$/ { # removed symbol
81   o=0+substr($3,2)
82   if (removed[o] == "" || removed[o] == $2) {
83      removed[o] = $2
84      if (o > symbolo) symbolo = o
85   } else {
86      print "png.h: duplicated removed symbol", o ": '" removed[o] "' != '" $2 "'"
87      err = 1
88   }
89   next
90}
91NF==2 && $2 ~ /^@[1-9][0-9]*$/ { # exported symbol
92   o=0+substr($2,2)
93   if (symbol[o] == "" || symbol[o] == $1) {
94      symbol[o] = $1
95      if (o > symbolo) symbolo = o
96   } else {
97      print "png.h: duplicated symbol", o ": '" symbol[o] "' != '" $1 "'"
98      err = 1
99   }
100}
101{
102   next # skip all other lines
103}
104
105# At the end check for symbols marked as both duplicated and removed
106END{
107   if (symbolo > lasto) {
108      print "highest symbol ordinal in png.h,", symbolo ", exceeds last ordinal from png.h", lasto
109      err = 1
110   }
111   if (mastero > lasto) {
112      print "highest symbol ordinal in", master ",", mastero ", exceeds last ordinal from png.h", lasto
113      err = 1
114   }
115   unexported=0
116   # Add a standard header to symbols.new:
117   print ";Version INSERT-VERSION-HERE" >of
118   print ";--------------------------------------------------------------" >of
119   print "; LIBPNG symbol list as a Win32 DEF file" >of
120   print "; Contains all the symbols that can be exported from libpng" >of
121   print ";--------------------------------------------------------------" >of
122   print "LIBRARY" >of
123   print "" >of
124   print "EXPORTS" >of
125
126   for (o=1; o<=lasto; ++o) {
127      if (symbol[o] == "" && removed[o] == "") {
128         if (unexported == 0) unexported = o
129         if (official[o] == "") {
130            # missing in export list too, so ok
131            if (o < lasto) continue
132         }
133      }
134      if (unexported != 0) {
135         # Symbols in the .def but not in the new file are errors, but
136         # the 'unexported' symbols aren't in either.  By default this
137         # is an error too (see the setting of 'missing' at the start),
138         # but this can be reset on the command line or by stuff in the
139         # file - see the comments above.
140         if (missing != "ignore") {
141            if (o-1 > unexported)
142               print "png.h:", missing ": missing symbols:", unexported "-" o-1
143            else
144               print "png.h:", missing ": missing symbol:", unexported
145            if (missing != "warning")
146               err = 1
147         }
148         unexported = 0
149      }
150      if (symbol[o] != "" && removed[o] != "") {
151         print "png.h: symbol", o, "both exported as '" symbol[o] "' and removed as '" removed[o] "'"
152         err = 1
153      } else if (symbol[o] != official[o]) {
154         # either the symbol is missing somewhere or it changed
155         err = 1
156         if (symbol[o] == "")
157            print "png.h: symbol", o, "is exported as '" official[o] "' in", master
158         else if (official[o] == "")
159            print "png.h: exported symbol", o, "'" symbol[o] "' not present in", master
160         else
161            print "png.h: exported symbol", o, "'" symbol[o] "' exists as '" official[o] "' in", master
162      }
163
164      # Finally generate symbols.new
165      if (symbol[o] != "")
166         print " " symbol[o], "@" o > of
167   }
168
169   if (err != 0) {
170      print "*** A new list is in", of, "***"
171      exit 1
172   }
173}
174