1 /* gzwrite.c -- zlib functions for writing gzip files
2 * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
9 local int gz_init OF((gz_statep));
10 local int gz_comp OF((gz_statep, int));
11 local int gz_zero OF((gz_statep, z_off64_t));
13 /* Initialize state for writing a gzip file. Mark initialization by setting
14 state->size to non-zero. Return -1 on failure or 0 on success. */
15 local int gz_init(state)
19 z_streamp strm = &(state->strm);
21 /* allocate input buffer */
22 state->in = (unsigned char *)malloc(state->want);
23 if (state->in == NULL) {
24 gz_error(state, Z_MEM_ERROR, "out of memory");
28 /* only need output buffer and deflate state if compressing */
30 /* allocate output buffer */
31 state->out = (unsigned char *)malloc(state->want);
32 if (state->out == NULL) {
34 gz_error(state, Z_MEM_ERROR, "out of memory");
38 /* allocate deflate memory, set up for gzip compression */
39 strm->zalloc = Z_NULL;
41 strm->opaque = Z_NULL;
42 ret = deflateInit2(strm, state->level, Z_DEFLATED,
43 MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
47 gz_error(state, Z_MEM_ERROR, "out of memory");
52 /* mark state as initialized */
53 state->size = state->want;
55 /* initialize write buffer if compressing */
57 strm->avail_out = state->size;
58 strm->next_out = state->out;
59 state->x.next = strm->next_out;
64 /* Compress whatever is at avail_in and next_in and write to the output file.
65 Return -1 if there is an error writing to the output file, otherwise 0.
66 flush is assumed to be a valid deflate() flush value. If flush is Z_FINISH,
67 then the deflate() state is reset to start a new gzip stream. If gz->direct
68 is true, then simply write to the output file without compressing, and
70 local int gz_comp(state, flush)
76 z_streamp strm = &(state->strm);
78 /* allocate memory if this is the first time through */
79 if (state->size == 0 && gz_init(state) == -1)
82 /* write directly if requested */
84 got = write(state->fd, strm->next_in, strm->avail_in);
85 if (got < 0 || (unsigned)got != strm->avail_in) {
86 gz_error(state, Z_ERRNO, zstrerror());
93 /* run deflate() on provided input until it produces no more output */
96 /* write out current buffer contents if full, or if flushing, but if
97 doing Z_FINISH then don't write until we get to Z_STREAM_END */
98 if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
99 (flush != Z_FINISH || ret == Z_STREAM_END))) {
100 have = (unsigned)(strm->next_out - state->x.next);
101 if (have && ((got = write(state->fd, state->x.next, have)) < 0 ||
102 (unsigned)got != have)) {
103 gz_error(state, Z_ERRNO, zstrerror());
106 if (strm->avail_out == 0) {
107 strm->avail_out = state->size;
108 strm->next_out = state->out;
110 state->x.next = strm->next_out;
114 have = strm->avail_out;
115 ret = deflate(strm, flush);
116 if (ret == Z_STREAM_ERROR) {
117 gz_error(state, Z_STREAM_ERROR,
118 "internal error: deflate stream corrupt");
121 have -= strm->avail_out;
124 /* if that completed a deflate stream, allow another to start */
125 if (flush == Z_FINISH)
128 /* all done, no errors */
132 /* Compress len zeros to output. Return -1 on error, 0 on success. */
133 local int gz_zero(state, len)
139 z_streamp strm = &(state->strm);
141 /* consume whatever's left in the input buffer */
142 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
145 /* compress len zeros (len guaranteed > 0) */
148 n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
149 (unsigned)len : state->size;
151 memset(state->in, 0, n);
155 strm->next_in = state->in;
157 if (gz_comp(state, Z_NO_FLUSH) == -1)
164 /* -- see zlib.h -- */
165 int ZEXPORT gzwrite(file, buf, len)
174 /* get internal structure */
177 state = (gz_statep)file;
178 strm = &(state->strm);
180 /* check that we're writing and that there's no error */
181 if (state->mode != GZ_WRITE || state->err != Z_OK)
184 /* since an int is returned, make sure len fits in one, otherwise return
185 with an error (this avoids the flaw in the interface) */
187 gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
191 /* if len is zero, avoid unnecessary operations */
195 /* allocate memory if this is the first time through */
196 if (state->size == 0 && gz_init(state) == -1)
199 /* check for seek request */
202 if (gz_zero(state, state->skip) == -1)
206 /* for small len, copy to input buffer, otherwise compress directly */
207 if (len < state->size) {
208 /* copy to input buffer, compress when full */
212 if (strm->avail_in == 0)
213 strm->next_in = state->in;
214 have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
215 copy = state->size - have;
218 memcpy(state->in + have, buf, copy);
219 strm->avail_in += copy;
220 state->x.pos += copy;
221 buf = (const char *)buf + copy;
223 if (len && gz_comp(state, Z_NO_FLUSH) == -1)
228 /* consume whatever's left in the input buffer */
229 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
232 /* directly compress user buffer to file */
233 strm->avail_in = len;
234 strm->next_in = (z_const Bytef *)buf;
236 if (gz_comp(state, Z_NO_FLUSH) == -1)
240 /* input was all buffered or compressed (put will fit in int) */
244 /* -- see zlib.h -- */
245 int ZEXPORT gzputc(file, c)
250 unsigned char buf[1];
254 /* get internal structure */
257 state = (gz_statep)file;
258 strm = &(state->strm);
260 /* check that we're writing and that there's no error */
261 if (state->mode != GZ_WRITE || state->err != Z_OK)
264 /* check for seek request */
267 if (gz_zero(state, state->skip) == -1)
271 /* try writing to input buffer for speed (state->size == 0 if buffer not
274 if (strm->avail_in == 0)
275 strm->next_in = state->in;
276 have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
277 if (have < state->size) {
285 /* no room in buffer or not initialized, use gz_write() */
287 if (gzwrite(file, buf, 1) != 1)
292 /* -- see zlib.h -- */
293 int ZEXPORT gzputs(file, str)
301 len = (unsigned)strlen(str);
302 ret = gzwrite(file, str, len);
303 return ret == 0 && len != 0 ? -1 : ret;
306 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
309 /* -- see zlib.h -- */
310 int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
316 /* get internal structure */
319 state = (gz_statep)file;
320 strm = &(state->strm);
322 /* check that we're writing and that there's no error */
323 if (state->mode != GZ_WRITE || state->err != Z_OK)
326 /* make sure we have some buffer space */
327 if (state->size == 0 && gz_init(state) == -1)
330 /* check for seek request */
333 if (gz_zero(state, state->skip) == -1)
337 /* consume whatever's left in the input buffer */
338 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
341 /* do the printf() into the input buffer, put length in len */
342 size = (int)(state->size);
343 state->in[size - 1] = 0;
345 # ifdef HAS_vsprintf_void
346 (void)vsprintf((char *)(state->in), format, va);
347 for (len = 0; len < size; len++)
348 if (state->in[len] == 0) break;
350 len = vsprintf((char *)(state->in), format, va);
353 # ifdef HAS_vsnprintf_void
354 (void)vsnprintf((char *)(state->in), size, format, va);
355 len = strlen((char *)(state->in));
357 len = vsnprintf((char *)(state->in), size, format, va);
361 /* check that printf() results fit in buffer */
362 if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
365 /* update buffer and position, defer compression until needed */
366 strm->avail_in = (unsigned)len;
367 strm->next_in = state->in;
372 int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
377 va_start(va, format);
378 ret = gzvprintf(file, format, va);
383 #else /* !STDC && !Z_HAVE_STDARG_H */
385 /* -- see zlib.h -- */
386 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
387 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
390 int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
391 a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
397 /* get internal structure */
400 state = (gz_statep)file;
401 strm = &(state->strm);
403 /* check that can really pass pointer in ints */
404 if (sizeof(int) != sizeof(void *))
407 /* check that we're writing and that there's no error */
408 if (state->mode != GZ_WRITE || state->err != Z_OK)
411 /* make sure we have some buffer space */
412 if (state->size == 0 && gz_init(state) == -1)
415 /* check for seek request */
418 if (gz_zero(state, state->skip) == -1)
422 /* consume whatever's left in the input buffer */
423 if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
426 /* do the printf() into the input buffer, put length in len */
427 size = (int)(state->size);
428 state->in[size - 1] = 0;
430 # ifdef HAS_sprintf_void
431 sprintf((char *)(state->in), format, a1, a2, a3, a4, a5, a6, a7, a8,
432 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
433 for (len = 0; len < size; len++)
434 if (state->in[len] == 0) break;
436 len = sprintf((char *)(state->in), format, a1, a2, a3, a4, a5, a6, a7, a8,
437 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
440 # ifdef HAS_snprintf_void
441 snprintf((char *)(state->in), size, format, a1, a2, a3, a4, a5, a6, a7, a8,
442 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
443 len = strlen((char *)(state->in));
445 len = snprintf((char *)(state->in), size, format, a1, a2, a3, a4, a5, a6,
446 a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18,
451 /* check that printf() results fit in buffer */
452 if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
455 /* update buffer and position, defer compression until needed */
456 strm->avail_in = (unsigned)len;
457 strm->next_in = state->in;
464 /* -- see zlib.h -- */
465 int ZEXPORT gzflush(file, flush)
471 /* get internal structure */
474 state = (gz_statep)file;
476 /* check that we're writing and that there's no error */
477 if (state->mode != GZ_WRITE || state->err != Z_OK)
478 return Z_STREAM_ERROR;
480 /* check flush parameter */
481 if (flush < 0 || flush > Z_FINISH)
482 return Z_STREAM_ERROR;
484 /* check for seek request */
487 if (gz_zero(state, state->skip) == -1)
491 /* compress remaining data with requested flush */
492 gz_comp(state, flush);
496 /* -- see zlib.h -- */
497 int ZEXPORT gzsetparams(file, level, strategy)
505 /* get internal structure */
507 return Z_STREAM_ERROR;
508 state = (gz_statep)file;
509 strm = &(state->strm);
511 /* check that we're writing and that there's no error */
512 if (state->mode != GZ_WRITE || state->err != Z_OK)
513 return Z_STREAM_ERROR;
515 /* if no change is requested, then do nothing */
516 if (level == state->level && strategy == state->strategy)
519 /* check for seek request */
522 if (gz_zero(state, state->skip) == -1)
526 /* change compression parameters for subsequent input */
528 /* flush previous input with previous parameters before changing */
529 if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1)
531 deflateParams(strm, level, strategy);
533 state->level = level;
534 state->strategy = strategy;
538 /* -- see zlib.h -- */
539 int ZEXPORT gzclose_w(file)
545 /* get internal structure */
547 return Z_STREAM_ERROR;
548 state = (gz_statep)file;
550 /* check that we're writing */
551 if (state->mode != GZ_WRITE)
552 return Z_STREAM_ERROR;
554 /* check for seek request */
557 if (gz_zero(state, state->skip) == -1)
561 /* flush, free memory, and close file */
562 if (gz_comp(state, Z_FINISH) == -1)
565 if (!state->direct) {
566 (void)deflateEnd(&(state->strm));
571 gz_error(state, Z_OK, NULL);
573 if (close(state->fd) == -1)