annotate zlib/gzread.c @ 158:494b0b89df80 default tip

...
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Mon, 25 May 2020 18:13:55 +0900
parents 04ced10e8804
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
111
kono
parents:
diff changeset
1 /* gzread.c -- zlib functions for reading gzip files
kono
parents:
diff changeset
2 * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
kono
parents:
diff changeset
3 * For conditions of distribution and use, see copyright notice in zlib.h
kono
parents:
diff changeset
4 */
kono
parents:
diff changeset
5
kono
parents:
diff changeset
6 #include "gzguts.h"
kono
parents:
diff changeset
7
kono
parents:
diff changeset
8 /* Local functions */
kono
parents:
diff changeset
9 local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));
kono
parents:
diff changeset
10 local int gz_avail OF((gz_statep));
kono
parents:
diff changeset
11 local int gz_look OF((gz_statep));
kono
parents:
diff changeset
12 local int gz_decomp OF((gz_statep));
kono
parents:
diff changeset
13 local int gz_fetch OF((gz_statep));
kono
parents:
diff changeset
14 local int gz_skip OF((gz_statep, z_off64_t));
kono
parents:
diff changeset
15 local z_size_t gz_read OF((gz_statep, voidp, z_size_t));
kono
parents:
diff changeset
16
kono
parents:
diff changeset
17 /* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from
kono
parents:
diff changeset
18 state->fd, and update state->eof, state->err, and state->msg as appropriate.
kono
parents:
diff changeset
19 This function needs to loop on read(), since read() is not guaranteed to
kono
parents:
diff changeset
20 read the number of bytes requested, depending on the type of descriptor. */
kono
parents:
diff changeset
21 local int gz_load(state, buf, len, have)
kono
parents:
diff changeset
22 gz_statep state;
kono
parents:
diff changeset
23 unsigned char *buf;
kono
parents:
diff changeset
24 unsigned len;
kono
parents:
diff changeset
25 unsigned *have;
kono
parents:
diff changeset
26 {
kono
parents:
diff changeset
27 int ret;
kono
parents:
diff changeset
28 unsigned get, max = ((unsigned)-1 >> 2) + 1;
kono
parents:
diff changeset
29
kono
parents:
diff changeset
30 *have = 0;
kono
parents:
diff changeset
31 do {
kono
parents:
diff changeset
32 get = len - *have;
kono
parents:
diff changeset
33 if (get > max)
kono
parents:
diff changeset
34 get = max;
kono
parents:
diff changeset
35 ret = read(state->fd, buf + *have, get);
kono
parents:
diff changeset
36 if (ret <= 0)
kono
parents:
diff changeset
37 break;
kono
parents:
diff changeset
38 *have += (unsigned)ret;
kono
parents:
diff changeset
39 } while (*have < len);
kono
parents:
diff changeset
40 if (ret < 0) {
kono
parents:
diff changeset
41 gz_error(state, Z_ERRNO, zstrerror());
kono
parents:
diff changeset
42 return -1;
kono
parents:
diff changeset
43 }
kono
parents:
diff changeset
44 if (ret == 0)
kono
parents:
diff changeset
45 state->eof = 1;
kono
parents:
diff changeset
46 return 0;
kono
parents:
diff changeset
47 }
kono
parents:
diff changeset
48
kono
parents:
diff changeset
49 /* Load up input buffer and set eof flag if last data loaded -- return -1 on
kono
parents:
diff changeset
50 error, 0 otherwise. Note that the eof flag is set when the end of the input
kono
parents:
diff changeset
51 file is reached, even though there may be unused data in the buffer. Once
kono
parents:
diff changeset
52 that data has been used, no more attempts will be made to read the file.
kono
parents:
diff changeset
53 If strm->avail_in != 0, then the current data is moved to the beginning of
kono
parents:
diff changeset
54 the input buffer, and then the remainder of the buffer is loaded with the
kono
parents:
diff changeset
55 available data from the input file. */
kono
parents:
diff changeset
56 local int gz_avail(state)
kono
parents:
diff changeset
57 gz_statep state;
kono
parents:
diff changeset
58 {
kono
parents:
diff changeset
59 unsigned got;
kono
parents:
diff changeset
60 z_streamp strm = &(state->strm);
kono
parents:
diff changeset
61
kono
parents:
diff changeset
62 if (state->err != Z_OK && state->err != Z_BUF_ERROR)
kono
parents:
diff changeset
63 return -1;
kono
parents:
diff changeset
64 if (state->eof == 0) {
kono
parents:
diff changeset
65 if (strm->avail_in) { /* copy what's there to the start */
kono
parents:
diff changeset
66 unsigned char *p = state->in;
kono
parents:
diff changeset
67 unsigned const char *q = strm->next_in;
kono
parents:
diff changeset
68 unsigned n = strm->avail_in;
kono
parents:
diff changeset
69 do {
kono
parents:
diff changeset
70 *p++ = *q++;
kono
parents:
diff changeset
71 } while (--n);
kono
parents:
diff changeset
72 }
kono
parents:
diff changeset
73 if (gz_load(state, state->in + strm->avail_in,
kono
parents:
diff changeset
74 state->size - strm->avail_in, &got) == -1)
kono
parents:
diff changeset
75 return -1;
kono
parents:
diff changeset
76 strm->avail_in += got;
kono
parents:
diff changeset
77 strm->next_in = state->in;
kono
parents:
diff changeset
78 }
kono
parents:
diff changeset
79 return 0;
kono
parents:
diff changeset
80 }
kono
parents:
diff changeset
81
kono
parents:
diff changeset
82 /* Look for gzip header, set up for inflate or copy. state->x.have must be 0.
kono
parents:
diff changeset
83 If this is the first time in, allocate required memory. state->how will be
kono
parents:
diff changeset
84 left unchanged if there is no more input data available, will be set to COPY
kono
parents:
diff changeset
85 if there is no gzip header and direct copying will be performed, or it will
kono
parents:
diff changeset
86 be set to GZIP for decompression. If direct copying, then leftover input
kono
parents:
diff changeset
87 data from the input buffer will be copied to the output buffer. In that
kono
parents:
diff changeset
88 case, all further file reads will be directly to either the output buffer or
kono
parents:
diff changeset
89 a user buffer. If decompressing, the inflate state will be initialized.
kono
parents:
diff changeset
90 gz_look() will return 0 on success or -1 on failure. */
kono
parents:
diff changeset
91 local int gz_look(state)
kono
parents:
diff changeset
92 gz_statep state;
kono
parents:
diff changeset
93 {
kono
parents:
diff changeset
94 z_streamp strm = &(state->strm);
kono
parents:
diff changeset
95
kono
parents:
diff changeset
96 /* allocate read buffers and inflate memory */
kono
parents:
diff changeset
97 if (state->size == 0) {
kono
parents:
diff changeset
98 /* allocate buffers */
kono
parents:
diff changeset
99 state->in = (unsigned char *)malloc(state->want);
kono
parents:
diff changeset
100 state->out = (unsigned char *)malloc(state->want << 1);
kono
parents:
diff changeset
101 if (state->in == NULL || state->out == NULL) {
kono
parents:
diff changeset
102 free(state->out);
kono
parents:
diff changeset
103 free(state->in);
kono
parents:
diff changeset
104 gz_error(state, Z_MEM_ERROR, "out of memory");
kono
parents:
diff changeset
105 return -1;
kono
parents:
diff changeset
106 }
kono
parents:
diff changeset
107 state->size = state->want;
kono
parents:
diff changeset
108
kono
parents:
diff changeset
109 /* allocate inflate memory */
kono
parents:
diff changeset
110 state->strm.zalloc = Z_NULL;
kono
parents:
diff changeset
111 state->strm.zfree = Z_NULL;
kono
parents:
diff changeset
112 state->strm.opaque = Z_NULL;
kono
parents:
diff changeset
113 state->strm.avail_in = 0;
kono
parents:
diff changeset
114 state->strm.next_in = Z_NULL;
kono
parents:
diff changeset
115 if (inflateInit2(&(state->strm), 15 + 16) != Z_OK) { /* gunzip */
kono
parents:
diff changeset
116 free(state->out);
kono
parents:
diff changeset
117 free(state->in);
kono
parents:
diff changeset
118 state->size = 0;
kono
parents:
diff changeset
119 gz_error(state, Z_MEM_ERROR, "out of memory");
kono
parents:
diff changeset
120 return -1;
kono
parents:
diff changeset
121 }
kono
parents:
diff changeset
122 }
kono
parents:
diff changeset
123
kono
parents:
diff changeset
124 /* get at least the magic bytes in the input buffer */
kono
parents:
diff changeset
125 if (strm->avail_in < 2) {
kono
parents:
diff changeset
126 if (gz_avail(state) == -1)
kono
parents:
diff changeset
127 return -1;
kono
parents:
diff changeset
128 if (strm->avail_in == 0)
kono
parents:
diff changeset
129 return 0;
kono
parents:
diff changeset
130 }
kono
parents:
diff changeset
131
kono
parents:
diff changeset
132 /* look for gzip magic bytes -- if there, do gzip decoding (note: there is
kono
parents:
diff changeset
133 a logical dilemma here when considering the case of a partially written
kono
parents:
diff changeset
134 gzip file, to wit, if a single 31 byte is written, then we cannot tell
kono
parents:
diff changeset
135 whether this is a single-byte file, or just a partially written gzip
kono
parents:
diff changeset
136 file -- for here we assume that if a gzip file is being written, then
kono
parents:
diff changeset
137 the header will be written in a single operation, so that reading a
kono
parents:
diff changeset
138 single byte is sufficient indication that it is not a gzip file) */
kono
parents:
diff changeset
139 if (strm->avail_in > 1 &&
kono
parents:
diff changeset
140 strm->next_in[0] == 31 && strm->next_in[1] == 139) {
kono
parents:
diff changeset
141 inflateReset(strm);
kono
parents:
diff changeset
142 state->how = GZIP;
kono
parents:
diff changeset
143 state->direct = 0;
kono
parents:
diff changeset
144 return 0;
kono
parents:
diff changeset
145 }
kono
parents:
diff changeset
146
kono
parents:
diff changeset
147 /* no gzip header -- if we were decoding gzip before, then this is trailing
kono
parents:
diff changeset
148 garbage. Ignore the trailing garbage and finish. */
kono
parents:
diff changeset
149 if (state->direct == 0) {
kono
parents:
diff changeset
150 strm->avail_in = 0;
kono
parents:
diff changeset
151 state->eof = 1;
kono
parents:
diff changeset
152 state->x.have = 0;
kono
parents:
diff changeset
153 return 0;
kono
parents:
diff changeset
154 }
kono
parents:
diff changeset
155
kono
parents:
diff changeset
156 /* doing raw i/o, copy any leftover input to output -- this assumes that
kono
parents:
diff changeset
157 the output buffer is larger than the input buffer, which also assures
kono
parents:
diff changeset
158 space for gzungetc() */
kono
parents:
diff changeset
159 state->x.next = state->out;
kono
parents:
diff changeset
160 if (strm->avail_in) {
kono
parents:
diff changeset
161 memcpy(state->x.next, strm->next_in, strm->avail_in);
kono
parents:
diff changeset
162 state->x.have = strm->avail_in;
kono
parents:
diff changeset
163 strm->avail_in = 0;
kono
parents:
diff changeset
164 }
kono
parents:
diff changeset
165 state->how = COPY;
kono
parents:
diff changeset
166 state->direct = 1;
kono
parents:
diff changeset
167 return 0;
kono
parents:
diff changeset
168 }
kono
parents:
diff changeset
169
kono
parents:
diff changeset
170 /* Decompress from input to the provided next_out and avail_out in the state.
kono
parents:
diff changeset
171 On return, state->x.have and state->x.next point to the just decompressed
kono
parents:
diff changeset
172 data. If the gzip stream completes, state->how is reset to LOOK to look for
kono
parents:
diff changeset
173 the next gzip stream or raw data, once state->x.have is depleted. Returns 0
kono
parents:
diff changeset
174 on success, -1 on failure. */
kono
parents:
diff changeset
175 local int gz_decomp(state)
kono
parents:
diff changeset
176 gz_statep state;
kono
parents:
diff changeset
177 {
kono
parents:
diff changeset
178 int ret = Z_OK;
kono
parents:
diff changeset
179 unsigned had;
kono
parents:
diff changeset
180 z_streamp strm = &(state->strm);
kono
parents:
diff changeset
181
kono
parents:
diff changeset
182 /* fill output buffer up to end of deflate stream */
kono
parents:
diff changeset
183 had = strm->avail_out;
kono
parents:
diff changeset
184 do {
kono
parents:
diff changeset
185 /* get more input for inflate() */
kono
parents:
diff changeset
186 if (strm->avail_in == 0 && gz_avail(state) == -1)
kono
parents:
diff changeset
187 return -1;
kono
parents:
diff changeset
188 if (strm->avail_in == 0) {
kono
parents:
diff changeset
189 gz_error(state, Z_BUF_ERROR, "unexpected end of file");
kono
parents:
diff changeset
190 break;
kono
parents:
diff changeset
191 }
kono
parents:
diff changeset
192
kono
parents:
diff changeset
193 /* decompress and handle errors */
kono
parents:
diff changeset
194 ret = inflate(strm, Z_NO_FLUSH);
kono
parents:
diff changeset
195 if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {
kono
parents:
diff changeset
196 gz_error(state, Z_STREAM_ERROR,
kono
parents:
diff changeset
197 "internal error: inflate stream corrupt");
kono
parents:
diff changeset
198 return -1;
kono
parents:
diff changeset
199 }
kono
parents:
diff changeset
200 if (ret == Z_MEM_ERROR) {
kono
parents:
diff changeset
201 gz_error(state, Z_MEM_ERROR, "out of memory");
kono
parents:
diff changeset
202 return -1;
kono
parents:
diff changeset
203 }
kono
parents:
diff changeset
204 if (ret == Z_DATA_ERROR) { /* deflate stream invalid */
kono
parents:
diff changeset
205 gz_error(state, Z_DATA_ERROR,
kono
parents:
diff changeset
206 strm->msg == NULL ? "compressed data error" : strm->msg);
kono
parents:
diff changeset
207 return -1;
kono
parents:
diff changeset
208 }
kono
parents:
diff changeset
209 } while (strm->avail_out && ret != Z_STREAM_END);
kono
parents:
diff changeset
210
kono
parents:
diff changeset
211 /* update available output */
kono
parents:
diff changeset
212 state->x.have = had - strm->avail_out;
kono
parents:
diff changeset
213 state->x.next = strm->next_out - state->x.have;
kono
parents:
diff changeset
214
kono
parents:
diff changeset
215 /* if the gzip stream completed successfully, look for another */
kono
parents:
diff changeset
216 if (ret == Z_STREAM_END)
kono
parents:
diff changeset
217 state->how = LOOK;
kono
parents:
diff changeset
218
kono
parents:
diff changeset
219 /* good decompression */
kono
parents:
diff changeset
220 return 0;
kono
parents:
diff changeset
221 }
kono
parents:
diff changeset
222
kono
parents:
diff changeset
223 /* Fetch data and put it in the output buffer. Assumes state->x.have is 0.
kono
parents:
diff changeset
224 Data is either copied from the input file or decompressed from the input
kono
parents:
diff changeset
225 file depending on state->how. If state->how is LOOK, then a gzip header is
kono
parents:
diff changeset
226 looked for to determine whether to copy or decompress. Returns -1 on error,
kono
parents:
diff changeset
227 otherwise 0. gz_fetch() will leave state->how as COPY or GZIP unless the
kono
parents:
diff changeset
228 end of the input file has been reached and all data has been processed. */
kono
parents:
diff changeset
229 local int gz_fetch(state)
kono
parents:
diff changeset
230 gz_statep state;
kono
parents:
diff changeset
231 {
kono
parents:
diff changeset
232 z_streamp strm = &(state->strm);
kono
parents:
diff changeset
233
kono
parents:
diff changeset
234 do {
kono
parents:
diff changeset
235 switch(state->how) {
kono
parents:
diff changeset
236 case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */
kono
parents:
diff changeset
237 if (gz_look(state) == -1)
kono
parents:
diff changeset
238 return -1;
kono
parents:
diff changeset
239 if (state->how == LOOK)
kono
parents:
diff changeset
240 return 0;
kono
parents:
diff changeset
241 break;
kono
parents:
diff changeset
242 case COPY: /* -> COPY */
kono
parents:
diff changeset
243 if (gz_load(state, state->out, state->size << 1, &(state->x.have))
kono
parents:
diff changeset
244 == -1)
kono
parents:
diff changeset
245 return -1;
kono
parents:
diff changeset
246 state->x.next = state->out;
kono
parents:
diff changeset
247 return 0;
kono
parents:
diff changeset
248 case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */
kono
parents:
diff changeset
249 strm->avail_out = state->size << 1;
kono
parents:
diff changeset
250 strm->next_out = state->out;
kono
parents:
diff changeset
251 if (gz_decomp(state) == -1)
kono
parents:
diff changeset
252 return -1;
kono
parents:
diff changeset
253 }
kono
parents:
diff changeset
254 } while (state->x.have == 0 && (!state->eof || strm->avail_in));
kono
parents:
diff changeset
255 return 0;
kono
parents:
diff changeset
256 }
kono
parents:
diff changeset
257
kono
parents:
diff changeset
258 /* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */
kono
parents:
diff changeset
259 local int gz_skip(state, len)
kono
parents:
diff changeset
260 gz_statep state;
kono
parents:
diff changeset
261 z_off64_t len;
kono
parents:
diff changeset
262 {
kono
parents:
diff changeset
263 unsigned n;
kono
parents:
diff changeset
264
kono
parents:
diff changeset
265 /* skip over len bytes or reach end-of-file, whichever comes first */
kono
parents:
diff changeset
266 while (len)
kono
parents:
diff changeset
267 /* skip over whatever is in output buffer */
kono
parents:
diff changeset
268 if (state->x.have) {
kono
parents:
diff changeset
269 n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > len ?
kono
parents:
diff changeset
270 (unsigned)len : state->x.have;
kono
parents:
diff changeset
271 state->x.have -= n;
kono
parents:
diff changeset
272 state->x.next += n;
kono
parents:
diff changeset
273 state->x.pos += n;
kono
parents:
diff changeset
274 len -= n;
kono
parents:
diff changeset
275 }
kono
parents:
diff changeset
276
kono
parents:
diff changeset
277 /* output buffer empty -- return if we're at the end of the input */
kono
parents:
diff changeset
278 else if (state->eof && state->strm.avail_in == 0)
kono
parents:
diff changeset
279 break;
kono
parents:
diff changeset
280
kono
parents:
diff changeset
281 /* need more data to skip -- load up output buffer */
kono
parents:
diff changeset
282 else {
kono
parents:
diff changeset
283 /* get more output, looking for header if required */
kono
parents:
diff changeset
284 if (gz_fetch(state) == -1)
kono
parents:
diff changeset
285 return -1;
kono
parents:
diff changeset
286 }
kono
parents:
diff changeset
287 return 0;
kono
parents:
diff changeset
288 }
kono
parents:
diff changeset
289
kono
parents:
diff changeset
290 /* Read len bytes into buf from file, or less than len up to the end of the
kono
parents:
diff changeset
291 input. Return the number of bytes read. If zero is returned, either the
kono
parents:
diff changeset
292 end of file was reached, or there was an error. state->err must be
kono
parents:
diff changeset
293 consulted in that case to determine which. */
kono
parents:
diff changeset
294 local z_size_t gz_read(state, buf, len)
kono
parents:
diff changeset
295 gz_statep state;
kono
parents:
diff changeset
296 voidp buf;
kono
parents:
diff changeset
297 z_size_t len;
kono
parents:
diff changeset
298 {
kono
parents:
diff changeset
299 z_size_t got;
kono
parents:
diff changeset
300 unsigned n;
kono
parents:
diff changeset
301
kono
parents:
diff changeset
302 /* if len is zero, avoid unnecessary operations */
kono
parents:
diff changeset
303 if (len == 0)
kono
parents:
diff changeset
304 return 0;
kono
parents:
diff changeset
305
kono
parents:
diff changeset
306 /* process a skip request */
kono
parents:
diff changeset
307 if (state->seek) {
kono
parents:
diff changeset
308 state->seek = 0;
kono
parents:
diff changeset
309 if (gz_skip(state, state->skip) == -1)
kono
parents:
diff changeset
310 return 0;
kono
parents:
diff changeset
311 }
kono
parents:
diff changeset
312
kono
parents:
diff changeset
313 /* get len bytes to buf, or less than len if at the end */
kono
parents:
diff changeset
314 got = 0;
kono
parents:
diff changeset
315 do {
kono
parents:
diff changeset
316 /* set n to the maximum amount of len that fits in an unsigned int */
kono
parents:
diff changeset
317 n = -1;
kono
parents:
diff changeset
318 if (n > len)
kono
parents:
diff changeset
319 n = len;
kono
parents:
diff changeset
320
kono
parents:
diff changeset
321 /* first just try copying data from the output buffer */
kono
parents:
diff changeset
322 if (state->x.have) {
kono
parents:
diff changeset
323 if (state->x.have < n)
kono
parents:
diff changeset
324 n = state->x.have;
kono
parents:
diff changeset
325 memcpy(buf, state->x.next, n);
kono
parents:
diff changeset
326 state->x.next += n;
kono
parents:
diff changeset
327 state->x.have -= n;
kono
parents:
diff changeset
328 }
kono
parents:
diff changeset
329
kono
parents:
diff changeset
330 /* output buffer empty -- return if we're at the end of the input */
kono
parents:
diff changeset
331 else if (state->eof && state->strm.avail_in == 0) {
kono
parents:
diff changeset
332 state->past = 1; /* tried to read past end */
kono
parents:
diff changeset
333 break;
kono
parents:
diff changeset
334 }
kono
parents:
diff changeset
335
kono
parents:
diff changeset
336 /* need output data -- for small len or new stream load up our output
kono
parents:
diff changeset
337 buffer */
kono
parents:
diff changeset
338 else if (state->how == LOOK || n < (state->size << 1)) {
kono
parents:
diff changeset
339 /* get more output, looking for header if required */
kono
parents:
diff changeset
340 if (gz_fetch(state) == -1)
kono
parents:
diff changeset
341 return 0;
kono
parents:
diff changeset
342 continue; /* no progress yet -- go back to copy above */
kono
parents:
diff changeset
343 /* the copy above assures that we will leave with space in the
kono
parents:
diff changeset
344 output buffer, allowing at least one gzungetc() to succeed */
kono
parents:
diff changeset
345 }
kono
parents:
diff changeset
346
kono
parents:
diff changeset
347 /* large len -- read directly into user buffer */
kono
parents:
diff changeset
348 else if (state->how == COPY) { /* read directly */
kono
parents:
diff changeset
349 if (gz_load(state, (unsigned char *)buf, n, &n) == -1)
kono
parents:
diff changeset
350 return 0;
kono
parents:
diff changeset
351 }
kono
parents:
diff changeset
352
kono
parents:
diff changeset
353 /* large len -- decompress directly into user buffer */
kono
parents:
diff changeset
354 else { /* state->how == GZIP */
kono
parents:
diff changeset
355 state->strm.avail_out = n;
kono
parents:
diff changeset
356 state->strm.next_out = (unsigned char *)buf;
kono
parents:
diff changeset
357 if (gz_decomp(state) == -1)
kono
parents:
diff changeset
358 return 0;
kono
parents:
diff changeset
359 n = state->x.have;
kono
parents:
diff changeset
360 state->x.have = 0;
kono
parents:
diff changeset
361 }
kono
parents:
diff changeset
362
kono
parents:
diff changeset
363 /* update progress */
kono
parents:
diff changeset
364 len -= n;
kono
parents:
diff changeset
365 buf = (char *)buf + n;
kono
parents:
diff changeset
366 got += n;
kono
parents:
diff changeset
367 state->x.pos += n;
kono
parents:
diff changeset
368 } while (len);
kono
parents:
diff changeset
369
kono
parents:
diff changeset
370 /* return number of bytes read into user buffer */
kono
parents:
diff changeset
371 return got;
kono
parents:
diff changeset
372 }
kono
parents:
diff changeset
373
kono
parents:
diff changeset
374 /* -- see zlib.h -- */
kono
parents:
diff changeset
375 int ZEXPORT gzread(file, buf, len)
kono
parents:
diff changeset
376 gzFile file;
kono
parents:
diff changeset
377 voidp buf;
kono
parents:
diff changeset
378 unsigned len;
kono
parents:
diff changeset
379 {
kono
parents:
diff changeset
380 gz_statep state;
kono
parents:
diff changeset
381
kono
parents:
diff changeset
382 /* get internal structure */
kono
parents:
diff changeset
383 if (file == NULL)
kono
parents:
diff changeset
384 return -1;
kono
parents:
diff changeset
385 state = (gz_statep)file;
kono
parents:
diff changeset
386
kono
parents:
diff changeset
387 /* check that we're reading and that there's no (serious) error */
kono
parents:
diff changeset
388 if (state->mode != GZ_READ ||
kono
parents:
diff changeset
389 (state->err != Z_OK && state->err != Z_BUF_ERROR))
kono
parents:
diff changeset
390 return -1;
kono
parents:
diff changeset
391
kono
parents:
diff changeset
392 /* since an int is returned, make sure len fits in one, otherwise return
kono
parents:
diff changeset
393 with an error (this avoids a flaw in the interface) */
kono
parents:
diff changeset
394 if ((int)len < 0) {
kono
parents:
diff changeset
395 gz_error(state, Z_STREAM_ERROR, "request does not fit in an int");
kono
parents:
diff changeset
396 return -1;
kono
parents:
diff changeset
397 }
kono
parents:
diff changeset
398
kono
parents:
diff changeset
399 /* read len or fewer bytes to buf */
kono
parents:
diff changeset
400 len = gz_read(state, buf, len);
kono
parents:
diff changeset
401
kono
parents:
diff changeset
402 /* check for an error */
kono
parents:
diff changeset
403 if (len == 0 && state->err != Z_OK && state->err != Z_BUF_ERROR)
kono
parents:
diff changeset
404 return -1;
kono
parents:
diff changeset
405
kono
parents:
diff changeset
406 /* return the number of bytes read (this is assured to fit in an int) */
kono
parents:
diff changeset
407 return (int)len;
kono
parents:
diff changeset
408 }
kono
parents:
diff changeset
409
kono
parents:
diff changeset
410 /* -- see zlib.h -- */
kono
parents:
diff changeset
411 z_size_t ZEXPORT gzfread(buf, size, nitems, file)
kono
parents:
diff changeset
412 voidp buf;
kono
parents:
diff changeset
413 z_size_t size;
kono
parents:
diff changeset
414 z_size_t nitems;
kono
parents:
diff changeset
415 gzFile file;
kono
parents:
diff changeset
416 {
kono
parents:
diff changeset
417 z_size_t len;
kono
parents:
diff changeset
418 gz_statep state;
kono
parents:
diff changeset
419
kono
parents:
diff changeset
420 /* get internal structure */
kono
parents:
diff changeset
421 if (file == NULL)
kono
parents:
diff changeset
422 return 0;
kono
parents:
diff changeset
423 state = (gz_statep)file;
kono
parents:
diff changeset
424
kono
parents:
diff changeset
425 /* check that we're reading and that there's no (serious) error */
kono
parents:
diff changeset
426 if (state->mode != GZ_READ ||
kono
parents:
diff changeset
427 (state->err != Z_OK && state->err != Z_BUF_ERROR))
kono
parents:
diff changeset
428 return 0;
kono
parents:
diff changeset
429
kono
parents:
diff changeset
430 /* compute bytes to read -- error on overflow */
kono
parents:
diff changeset
431 len = nitems * size;
kono
parents:
diff changeset
432 if (size && len / size != nitems) {
kono
parents:
diff changeset
433 gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
kono
parents:
diff changeset
434 return 0;
kono
parents:
diff changeset
435 }
kono
parents:
diff changeset
436
kono
parents:
diff changeset
437 /* read len or fewer bytes to buf, return the number of full items read */
kono
parents:
diff changeset
438 return len ? gz_read(state, buf, len) / size : 0;
kono
parents:
diff changeset
439 }
kono
parents:
diff changeset
440
kono
parents:
diff changeset
441 /* -- see zlib.h -- */
kono
parents:
diff changeset
442 #ifdef Z_PREFIX_SET
kono
parents:
diff changeset
443 # undef z_gzgetc
kono
parents:
diff changeset
444 #else
kono
parents:
diff changeset
445 # undef gzgetc
kono
parents:
diff changeset
446 #endif
kono
parents:
diff changeset
447 int ZEXPORT gzgetc(file)
kono
parents:
diff changeset
448 gzFile file;
kono
parents:
diff changeset
449 {
kono
parents:
diff changeset
450 int ret;
kono
parents:
diff changeset
451 unsigned char buf[1];
kono
parents:
diff changeset
452 gz_statep state;
kono
parents:
diff changeset
453
kono
parents:
diff changeset
454 /* get internal structure */
kono
parents:
diff changeset
455 if (file == NULL)
kono
parents:
diff changeset
456 return -1;
kono
parents:
diff changeset
457 state = (gz_statep)file;
kono
parents:
diff changeset
458
kono
parents:
diff changeset
459 /* check that we're reading and that there's no (serious) error */
kono
parents:
diff changeset
460 if (state->mode != GZ_READ ||
kono
parents:
diff changeset
461 (state->err != Z_OK && state->err != Z_BUF_ERROR))
kono
parents:
diff changeset
462 return -1;
kono
parents:
diff changeset
463
kono
parents:
diff changeset
464 /* try output buffer (no need to check for skip request) */
kono
parents:
diff changeset
465 if (state->x.have) {
kono
parents:
diff changeset
466 state->x.have--;
kono
parents:
diff changeset
467 state->x.pos++;
kono
parents:
diff changeset
468 return *(state->x.next)++;
kono
parents:
diff changeset
469 }
kono
parents:
diff changeset
470
kono
parents:
diff changeset
471 /* nothing there -- try gz_read() */
kono
parents:
diff changeset
472 ret = gz_read(state, buf, 1);
kono
parents:
diff changeset
473 return ret < 1 ? -1 : buf[0];
kono
parents:
diff changeset
474 }
kono
parents:
diff changeset
475
kono
parents:
diff changeset
476 int ZEXPORT gzgetc_(file)
kono
parents:
diff changeset
477 gzFile file;
kono
parents:
diff changeset
478 {
kono
parents:
diff changeset
479 return gzgetc(file);
kono
parents:
diff changeset
480 }
kono
parents:
diff changeset
481
kono
parents:
diff changeset
482 /* -- see zlib.h -- */
kono
parents:
diff changeset
483 int ZEXPORT gzungetc(c, file)
kono
parents:
diff changeset
484 int c;
kono
parents:
diff changeset
485 gzFile file;
kono
parents:
diff changeset
486 {
kono
parents:
diff changeset
487 gz_statep state;
kono
parents:
diff changeset
488
kono
parents:
diff changeset
489 /* get internal structure */
kono
parents:
diff changeset
490 if (file == NULL)
kono
parents:
diff changeset
491 return -1;
kono
parents:
diff changeset
492 state = (gz_statep)file;
kono
parents:
diff changeset
493
kono
parents:
diff changeset
494 /* check that we're reading and that there's no (serious) error */
kono
parents:
diff changeset
495 if (state->mode != GZ_READ ||
kono
parents:
diff changeset
496 (state->err != Z_OK && state->err != Z_BUF_ERROR))
kono
parents:
diff changeset
497 return -1;
kono
parents:
diff changeset
498
kono
parents:
diff changeset
499 /* process a skip request */
kono
parents:
diff changeset
500 if (state->seek) {
kono
parents:
diff changeset
501 state->seek = 0;
kono
parents:
diff changeset
502 if (gz_skip(state, state->skip) == -1)
kono
parents:
diff changeset
503 return -1;
kono
parents:
diff changeset
504 }
kono
parents:
diff changeset
505
kono
parents:
diff changeset
506 /* can't push EOF */
kono
parents:
diff changeset
507 if (c < 0)
kono
parents:
diff changeset
508 return -1;
kono
parents:
diff changeset
509
kono
parents:
diff changeset
510 /* if output buffer empty, put byte at end (allows more pushing) */
kono
parents:
diff changeset
511 if (state->x.have == 0) {
kono
parents:
diff changeset
512 state->x.have = 1;
kono
parents:
diff changeset
513 state->x.next = state->out + (state->size << 1) - 1;
kono
parents:
diff changeset
514 state->x.next[0] = (unsigned char)c;
kono
parents:
diff changeset
515 state->x.pos--;
kono
parents:
diff changeset
516 state->past = 0;
kono
parents:
diff changeset
517 return c;
kono
parents:
diff changeset
518 }
kono
parents:
diff changeset
519
kono
parents:
diff changeset
520 /* if no room, give up (must have already done a gzungetc()) */
kono
parents:
diff changeset
521 if (state->x.have == (state->size << 1)) {
kono
parents:
diff changeset
522 gz_error(state, Z_DATA_ERROR, "out of room to push characters");
kono
parents:
diff changeset
523 return -1;
kono
parents:
diff changeset
524 }
kono
parents:
diff changeset
525
kono
parents:
diff changeset
526 /* slide output data if needed and insert byte before existing data */
kono
parents:
diff changeset
527 if (state->x.next == state->out) {
kono
parents:
diff changeset
528 unsigned char *src = state->out + state->x.have;
kono
parents:
diff changeset
529 unsigned char *dest = state->out + (state->size << 1);
kono
parents:
diff changeset
530 while (src > state->out)
kono
parents:
diff changeset
531 *--dest = *--src;
kono
parents:
diff changeset
532 state->x.next = dest;
kono
parents:
diff changeset
533 }
kono
parents:
diff changeset
534 state->x.have++;
kono
parents:
diff changeset
535 state->x.next--;
kono
parents:
diff changeset
536 state->x.next[0] = (unsigned char)c;
kono
parents:
diff changeset
537 state->x.pos--;
kono
parents:
diff changeset
538 state->past = 0;
kono
parents:
diff changeset
539 return c;
kono
parents:
diff changeset
540 }
kono
parents:
diff changeset
541
kono
parents:
diff changeset
542 /* -- see zlib.h -- */
kono
parents:
diff changeset
543 char * ZEXPORT gzgets(file, buf, len)
kono
parents:
diff changeset
544 gzFile file;
kono
parents:
diff changeset
545 char *buf;
kono
parents:
diff changeset
546 int len;
kono
parents:
diff changeset
547 {
kono
parents:
diff changeset
548 unsigned left, n;
kono
parents:
diff changeset
549 char *str;
kono
parents:
diff changeset
550 unsigned char *eol;
kono
parents:
diff changeset
551 gz_statep state;
kono
parents:
diff changeset
552
kono
parents:
diff changeset
553 /* check parameters and get internal structure */
kono
parents:
diff changeset
554 if (file == NULL || buf == NULL || len < 1)
kono
parents:
diff changeset
555 return NULL;
kono
parents:
diff changeset
556 state = (gz_statep)file;
kono
parents:
diff changeset
557
kono
parents:
diff changeset
558 /* check that we're reading and that there's no (serious) error */
kono
parents:
diff changeset
559 if (state->mode != GZ_READ ||
kono
parents:
diff changeset
560 (state->err != Z_OK && state->err != Z_BUF_ERROR))
kono
parents:
diff changeset
561 return NULL;
kono
parents:
diff changeset
562
kono
parents:
diff changeset
563 /* process a skip request */
kono
parents:
diff changeset
564 if (state->seek) {
kono
parents:
diff changeset
565 state->seek = 0;
kono
parents:
diff changeset
566 if (gz_skip(state, state->skip) == -1)
kono
parents:
diff changeset
567 return NULL;
kono
parents:
diff changeset
568 }
kono
parents:
diff changeset
569
kono
parents:
diff changeset
570 /* copy output bytes up to new line or len - 1, whichever comes first --
kono
parents:
diff changeset
571 append a terminating zero to the string (we don't check for a zero in
kono
parents:
diff changeset
572 the contents, let the user worry about that) */
kono
parents:
diff changeset
573 str = buf;
kono
parents:
diff changeset
574 left = (unsigned)len - 1;
kono
parents:
diff changeset
575 if (left) do {
kono
parents:
diff changeset
576 /* assure that something is in the output buffer */
kono
parents:
diff changeset
577 if (state->x.have == 0 && gz_fetch(state) == -1)
kono
parents:
diff changeset
578 return NULL; /* error */
kono
parents:
diff changeset
579 if (state->x.have == 0) { /* end of file */
kono
parents:
diff changeset
580 state->past = 1; /* read past end */
kono
parents:
diff changeset
581 break; /* return what we have */
kono
parents:
diff changeset
582 }
kono
parents:
diff changeset
583
kono
parents:
diff changeset
584 /* look for end-of-line in current output buffer */
kono
parents:
diff changeset
585 n = state->x.have > left ? left : state->x.have;
kono
parents:
diff changeset
586 eol = (unsigned char *)memchr(state->x.next, '\n', n);
kono
parents:
diff changeset
587 if (eol != NULL)
kono
parents:
diff changeset
588 n = (unsigned)(eol - state->x.next) + 1;
kono
parents:
diff changeset
589
kono
parents:
diff changeset
590 /* copy through end-of-line, or remainder if not found */
kono
parents:
diff changeset
591 memcpy(buf, state->x.next, n);
kono
parents:
diff changeset
592 state->x.have -= n;
kono
parents:
diff changeset
593 state->x.next += n;
kono
parents:
diff changeset
594 state->x.pos += n;
kono
parents:
diff changeset
595 left -= n;
kono
parents:
diff changeset
596 buf += n;
kono
parents:
diff changeset
597 } while (left && eol == NULL);
kono
parents:
diff changeset
598
kono
parents:
diff changeset
599 /* return terminated string, or if nothing, end of file */
kono
parents:
diff changeset
600 if (buf == str)
kono
parents:
diff changeset
601 return NULL;
kono
parents:
diff changeset
602 buf[0] = 0;
kono
parents:
diff changeset
603 return str;
kono
parents:
diff changeset
604 }
kono
parents:
diff changeset
605
kono
parents:
diff changeset
606 /* -- see zlib.h -- */
kono
parents:
diff changeset
607 int ZEXPORT gzdirect(file)
kono
parents:
diff changeset
608 gzFile file;
kono
parents:
diff changeset
609 {
kono
parents:
diff changeset
610 gz_statep state;
kono
parents:
diff changeset
611
kono
parents:
diff changeset
612 /* get internal structure */
kono
parents:
diff changeset
613 if (file == NULL)
kono
parents:
diff changeset
614 return 0;
kono
parents:
diff changeset
615 state = (gz_statep)file;
kono
parents:
diff changeset
616
kono
parents:
diff changeset
617 /* if the state is not known, but we can find out, then do so (this is
kono
parents:
diff changeset
618 mainly for right after a gzopen() or gzdopen()) */
kono
parents:
diff changeset
619 if (state->mode == GZ_READ && state->how == LOOK && state->x.have == 0)
kono
parents:
diff changeset
620 (void)gz_look(state);
kono
parents:
diff changeset
621
kono
parents:
diff changeset
622 /* return 1 if transparent, 0 if processing a gzip stream */
kono
parents:
diff changeset
623 return state->direct;
kono
parents:
diff changeset
624 }
kono
parents:
diff changeset
625
kono
parents:
diff changeset
626 /* -- see zlib.h -- */
kono
parents:
diff changeset
627 int ZEXPORT gzclose_r(file)
kono
parents:
diff changeset
628 gzFile file;
kono
parents:
diff changeset
629 {
kono
parents:
diff changeset
630 int ret, err;
kono
parents:
diff changeset
631 gz_statep state;
kono
parents:
diff changeset
632
kono
parents:
diff changeset
633 /* get internal structure */
kono
parents:
diff changeset
634 if (file == NULL)
kono
parents:
diff changeset
635 return Z_STREAM_ERROR;
kono
parents:
diff changeset
636 state = (gz_statep)file;
kono
parents:
diff changeset
637
kono
parents:
diff changeset
638 /* check that we're reading */
kono
parents:
diff changeset
639 if (state->mode != GZ_READ)
kono
parents:
diff changeset
640 return Z_STREAM_ERROR;
kono
parents:
diff changeset
641
kono
parents:
diff changeset
642 /* free memory and close file */
kono
parents:
diff changeset
643 if (state->size) {
kono
parents:
diff changeset
644 inflateEnd(&(state->strm));
kono
parents:
diff changeset
645 free(state->out);
kono
parents:
diff changeset
646 free(state->in);
kono
parents:
diff changeset
647 }
kono
parents:
diff changeset
648 err = state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK;
kono
parents:
diff changeset
649 gz_error(state, Z_OK, NULL);
kono
parents:
diff changeset
650 free(state->path);
kono
parents:
diff changeset
651 ret = close(state->fd);
kono
parents:
diff changeset
652 free(state);
kono
parents:
diff changeset
653 return ret ? Z_ERRNO : err;
kono
parents:
diff changeset
654 }