1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
/*
bash-inflate(){ (printf "\x1f\x8b\x08\x00\x00\x00\x00\x00\x00"&&cat -)|gzip -dc; }
*/
#include "commonbase.h"
/* system */
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
/* libs */
#include "zlib.h"
typedef unsigned char uchar; /* TODO cleanup */
typedef struct MyInflate MyInflate;
struct MyInflate {
int tryParseHeaders;
};
static void printHelp( void ){
printf("\n %s%s", strrchr(__FILE__,'/')+1, " " STR_QUOT(PROJECT_VERSION) "\n"
"\n"
" inflates stdin to stdout\n"
"\n"
" Options:\n"
"\n"
" --raw\n"
" By default, we'll try to decode leading headers. Using this\n"
" option, no header parsing is done and the input is expected to\n"
" be a pure deflate stream.\n"
"\n"
"\n");
}
static int parseArgs( int argc, char**argv, MyInflate*myInflate ){
myInflate->tryParseHeaders = !0; /* enabled by default */
for( int i = 1 ; i < argc ; ++i ){
char *arg = argv[i];
if( !strcmp(arg,"--help") ){
printHelp(); return -1;
}else if( !strcmp(arg,"--raw") ){
myInflate->tryParseHeaders = 0;
}else{
fprintf(stderr, "Unknown arg: %s\n", arg);
return -1;
}
}
return 0;
}
static int doInflate( MyInflate*myInflate ){
#define MAX(a, b) ((a) > (b) ? (a) : (b))
int err;
z_stream strm;
uchar innBuf[1<<18];
const int innBuf_cap = sizeof innBuf;
int innBuf_len = 0, innBuf_off = 0;
uchar outBuf[1<<18];
const int outBuf_cap = sizeof outBuf;
int outBuf_len = 0;
int inputIsEOF = 0;
int outputIsEOF = 0;
int noProgressSince = 0;
int numBufError = 0;
/* only counts while reading through possible file headers. Later, the
* counter will not be updated anymore, to prevent overflows */
int headerIsPassed = 0;
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
strm.next_in = innBuf;
strm.avail_in = 0;
// Pass special 2nd arg. See "https://codeandlife.com/2014/01/01/unzip-library-for-c/"
err = inflateInit2(&strm, -MAX_WBITS);
if( err != Z_OK ){
fprintf(stderr, "inflateInit(): r=%d: %s\n", err, strerror(errno));
return -1;
}
for(; !outputIsEOF ;){
/* input */ {
int space = innBuf_cap - innBuf_len;
/* look if we can shift */
if( space <= 0 && innBuf_off > 0 ){
int wr = 0, rd = innBuf_off;
for(;;){
err = rd - wr; /* chunk length to copy */
if( rd + err > innBuf_cap) err = innBuf_cap - rd;
if( err <= 0 ) break;
memcpy(innBuf + wr, innBuf + rd, err);
rd += err;
wr += err;
}
innBuf_len -= innBuf_off;
innBuf_off = 0;
space = innBuf_cap - innBuf_len;
}
if( space > 0 && !inputIsEOF ){
err = fread(innBuf + innBuf_len, 1, space, stdin);
//fprintf(stderr, "fread(buf+%d, 1, %d, stdin) -> %d\n", innBuf_len, space, err);
if(unlikely( err <= 0 )){
if( feof(stdin) ){
inputIsEOF = !0;
}else{
fprintf(stderr, "inflate fread(): %s\n", strerror(errno));
return -1;
}
}
assert(err <= space);
innBuf_len += err;
}
}
if(unlikely( !headerIsPassed )){
#define avail (innBuf_len - innBuf_off)
/* Ensure we have at least two bytes for zlib header detection */
if( avail < 2 && !inputIsEOF ){
//fprintf(stderr, "[DEBUG] Not enough data for header detection. have %d\n", avail);
continue;
}
headerIsPassed = !0;
if( myInflate->tryParseHeaders ){
int b0 = innBuf[0], b1 = innBuf[1];
if( b0 == 0x78 && (b1 == 0x01 || b1 == 0x5E || b1 == 0x9C || b1 == 0xDA) ){
/* Skip header. Because zlib would be confused as it
* doesn't expect it */
innBuf_off += 2;
}
}
#undef avail
}
/* process */ {
strm.next_in = innBuf + innBuf_off;
strm.avail_in = MAX(0, innBuf_len - innBuf_off);
strm.next_out = outBuf;
strm.avail_out = outBuf_cap;
// TODO remove assert(strm.avail_in >= 0 || inputIsEOF);
assert(strm.avail_out > 0);
int flush = inputIsEOF ? Z_FINISH : Z_NO_FLUSH;
errno = 0;
err = inflate(&strm, flush);
//fprintf(stderr, "inflate({.avI=%d, .avO=%d}, %d) -> %d\n", strm.avail_in, strm.avail_out,
// flush, err);
if(unlikely( err != Z_OK )){
if( err == Z_STREAM_END ){
outputIsEOF = !0;
goto errorsAreForSissies;
}
if( err == Z_DATA_ERROR ){
if( ++numBufError & 0xFFFF ){
/* TODO no idea why this occurs sometimes. Just
* retry a few times before giving up for now */
goto errorsAreForSissies;
}else{
/* No idea what to do now ... */
fprintf(stderr, "inflate Z_DATA_ERROR: %s\n",
(strm.msg != NULL) ? strm.msg : "(no detail)");
return -1;
}
}
numBufError = 0; /* reset just in case we'll get another case */
if( err == Z_BUF_ERROR ){
/* Could not make any progress. Have to call again
* with updated buffers */
noProgressSince += 1;
if( (noProgressSince & 0xFFFF) == 0){
fprintf(stderr, "inflate: Z_BUF_ERROR: %s\n",
(strm.msg != NULL) ? strm.msg : "(no detail)");
return -1;
}
}
noProgressSince = 0; /* reset just in case we'll get another case */
if( strm.msg != NULL || errno ){
fprintf(stderr, "inflate: Error: %s\n",
(strm.msg != NULL) ? strm.msg : strerror(errno));
return -1;
}
fprintf(stderr, "inflate(): %d\n", err);
return -1;
}
errorsAreForSissies: /* eh.. only an error. Just keep going :) */
innBuf_off += strm.next_in - innBuf;
outBuf_len = strm.next_out - outBuf;
if( innBuf_off > innBuf_len ){
innBuf_off = innBuf_len; }
}
/* output */ {
err = fwrite(outBuf, 1, outBuf_len, stdout);
if(unlikely( err != outBuf_len )){
fprintf(stderr, "inflate: fwrite(): %s\n", strerror(errno));
return -1;
}
outBuf_len = 0;
}
}
err = inflateEnd(&strm);
if( err != Z_OK ){
fprintf(stderr, "Warn: inflateEnd() ret=%d: %s\n", err, strm.msg);
}
return 0;
#undef MAX
}
int inflate_main( int argc, char**argv ){
int err;
MyInflate myInflate;
#define myInflate (&myInflate)
err = parseArgs(argc, argv, myInflate);
if( err < 0 ){ return err; }
fixBrokenStdio();
err = doInflate(myInflate);
if( err < 0 ){ return err; }
return 0;
#undef myInflate
}
|