tools/mtd-utils: avoid linking libm statically
[openwrt/openwrt.git] / scripts / cleanpatch
1 #!/usr/bin/perl -w
2 #
3 # Clean a patch file -- or directory of patch files -- of stealth whitespace.
4 # WARNING: this can be a highly destructive operation. Use with caution.
5 #
6
7 use bytes;
8 use File::Basename;
9
10 # Default options
11 $max_width = 79;
12
13 # Clean up space-tab sequences, either by removing spaces or
14 # replacing them with tabs.
15 sub clean_space_tabs($)
16 {
17 no bytes; # Tab alignment depends on characters
18
19 my($li) = @_;
20 my($lo) = '';
21 my $pos = 0;
22 my $nsp = 0;
23 my($i, $c);
24
25 for ($i = 0; $i < length($li); $i++) {
26 $c = substr($li, $i, 1);
27 if ($c eq "\t") {
28 my $npos = ($pos+$nsp+8) & ~7;
29 my $ntab = ($npos >> 3) - ($pos >> 3);
30 $lo .= "\t" x $ntab;
31 $pos = $npos;
32 $nsp = 0;
33 } elsif ($c eq "\n" || $c eq "\r") {
34 $lo .= " " x $nsp;
35 $pos += $nsp;
36 $nsp = 0;
37 $lo .= $c;
38 $pos = 0;
39 } elsif ($c eq " ") {
40 $nsp++;
41 } else {
42 $lo .= " " x $nsp;
43 $pos += $nsp;
44 $nsp = 0;
45 $lo .= $c;
46 $pos++;
47 }
48 }
49 $lo .= " " x $nsp;
50 return $lo;
51 }
52
53 # Compute the visual width of a string
54 sub strwidth($) {
55 no bytes; # Tab alignment depends on characters
56
57 my($li) = @_;
58 my($c, $i);
59 my $pos = 0;
60 my $mlen = 0;
61
62 for ($i = 0; $i < length($li); $i++) {
63 $c = substr($li,$i,1);
64 if ($c eq "\t") {
65 $pos = ($pos+8) & ~7;
66 } elsif ($c eq "\n") {
67 $mlen = $pos if ($pos > $mlen);
68 $pos = 0;
69 } else {
70 $pos++;
71 }
72 }
73
74 $mlen = $pos if ($pos > $mlen);
75 return $mlen;
76 }
77
78 $name = basename($0);
79
80 @files = ();
81
82 while (defined($a = shift(@ARGV))) {
83 if ($a =~ /^-/) {
84 if ($a eq '-width' || $a eq '-w') {
85 $max_width = shift(@ARGV)+0;
86 } else {
87 print STDERR "Usage: $name [-width #] files...\n";
88 exit 1;
89 }
90 } else {
91 push(@files, $a);
92 }
93 }
94
95 foreach $f ( @files ) {
96 print STDERR "$name: $f\n";
97
98 if (! -f $f) {
99 print STDERR "$f: not a file\n";
100 next;
101 }
102
103 if (!open(FILE, '+<', $f)) {
104 print STDERR "$name: Cannot open file: $f: $!\n";
105 next;
106 }
107
108 binmode FILE;
109
110 # First, verify that it is not a binary file; consider any file
111 # with a zero byte to be a binary file. Is there any better, or
112 # additional, heuristic that should be applied?
113 $is_binary = 0;
114
115 while (read(FILE, $data, 65536) > 0) {
116 if ($data =~ /\0/) {
117 $is_binary = 1;
118 last;
119 }
120 }
121
122 if ($is_binary) {
123 print STDERR "$name: $f: binary file\n";
124 next;
125 }
126
127 seek(FILE, 0, 0);
128
129 $in_bytes = 0;
130 $out_bytes = 0;
131 $lineno = 0;
132
133 @lines = ();
134
135 $in_hunk = 0;
136 $err = 0;
137
138 while ( defined($line = <FILE>) ) {
139 $lineno++;
140 $in_bytes += length($line);
141
142 if (!$in_hunk) {
143 if ($line =~
144 /^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@/) {
145 $minus_lines = $2;
146 $plus_lines = $4;
147 if ($minus_lines || $plus_lines) {
148 $in_hunk = 1;
149 @hunk_lines = ($line);
150 }
151 } else {
152 push(@lines, $line);
153 $out_bytes += length($line);
154 }
155 } else {
156 # We're in a hunk
157
158 if ($line =~ /^\+/) {
159 $plus_lines--;
160
161 $text = substr($line, 1);
162 $text =~ s/[ \t\r]*$//; # Remove trailing spaces
163 $text = clean_space_tabs($text);
164
165 $l_width = strwidth($text);
166 if ($max_width && $l_width > $max_width) {
167 print STDERR
168 "$f:$lineno: adds line exceeds $max_width ",
169 "characters ($l_width)\n";
170 }
171
172 push(@hunk_lines, '+'.$text);
173 } elsif ($line =~ /^\-/) {
174 $minus_lines--;
175 push(@hunk_lines, $line);
176 } elsif ($line =~ /^ /) {
177 $plus_lines--;
178 $minus_lines--;
179 push(@hunk_lines, $line);
180 } else {
181 print STDERR "$name: $f: malformed patch\n";
182 $err = 1;
183 last;
184 }
185
186 if ($plus_lines < 0 || $minus_lines < 0) {
187 print STDERR "$name: $f: malformed patch\n";
188 $err = 1;
189 last;
190 } elsif ($plus_lines == 0 && $minus_lines == 0) {
191 # End of a hunk. Process this hunk.
192 my $i;
193 my $l;
194 my @h = ();
195 my $adj = 0;
196 my $done = 0;
197
198 for ($i = scalar(@hunk_lines)-1; $i > 0; $i--) {
199 $l = $hunk_lines[$i];
200 if (!$done && $l eq "+\n") {
201 $adj++; # Skip this line
202 } elsif ($l =~ /^[ +]/) {
203 $done = 1;
204 unshift(@h, $l);
205 } else {
206 unshift(@h, $l);
207 }
208 }
209
210 $l = $hunk_lines[0]; # Hunk header
211 undef @hunk_lines; # Free memory
212
213 if ($adj) {
214 die unless
215 ($l =~ /^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@(.*)$/);
216 my $mstart = $1;
217 my $mlin = $2;
218 my $pstart = $3;
219 my $plin = $4;
220 my $tail = $5; # doesn't include the final newline
221
222 $l = sprintf("@@ -%d,%d +%d,%d @@%s\n",
223 $mstart, $mlin, $pstart, $plin-$adj,
224 $tail);
225 }
226 unshift(@h, $l);
227
228 # Transfer to the output array
229 foreach $l (@h) {
230 $out_bytes += length($l);
231 push(@lines, $l);
232 }
233
234 $in_hunk = 0;
235 }
236 }
237 }
238
239 if ($in_hunk) {
240 print STDERR "$name: $f: malformed patch\n";
241 $err = 1;
242 }
243
244 if (!$err) {
245 if ($in_bytes != $out_bytes) {
246 # Only write to the file if changed
247 seek(FILE, 0, 0);
248 print FILE @lines;
249
250 if ( !defined($where = tell(FILE)) ||
251 !truncate(FILE, $where) ) {
252 die "$name: Failed to truncate modified file: $f: $!\n";
253 }
254 }
255 }
256
257 close(FILE);
258 }