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
4 */
5
6#include "gzguts.h"
7
8/* Local functions */
9local int gz_init OF((gz_statep));
10local int gz_comp OF((gz_statep, int));
11local int gz_zero OF((gz_statep, z_off64_t));
12
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. */
15local int gz_init(state)
16    gz_statep state;
17{
18    int ret;
19    z_streamp strm = &(state->strm);
20
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");
25        return -1;
26    }
27
28    /* only need output buffer and deflate state if compressing */
29    if (!state->direct) {
30        /* allocate output buffer */
31        state->out = (unsigned char *)malloc(state->want);
32        if (state->out == NULL) {
33            free(state->in);
34            gz_error(state, Z_MEM_ERROR, "out of memory");
35            return -1;
36        }
37
38        /* allocate deflate memory, set up for gzip compression */
39        strm->zalloc = Z_NULL;
40        strm->zfree = Z_NULL;
41        strm->opaque = Z_NULL;
42        ret = deflateInit2(strm, state->level, Z_DEFLATED,
43                           MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
44        if (ret != Z_OK) {
45            free(state->out);
46            free(state->in);
47            gz_error(state, Z_MEM_ERROR, "out of memory");
48            return -1;
49        }
50    }
51
52    /* mark state as initialized */
53    state->size = state->want;
54
55    /* initialize write buffer if compressing */
56    if (!state->direct) {
57        strm->avail_out = state->size;
58        strm->next_out = state->out;
59        state->x.next = strm->next_out;
60    }
61    return 0;
62}
63
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
69   ignore flush. */
70local int gz_comp(state, flush)
71    gz_statep state;
72    int flush;
73{
74    int ret, got;
75    unsigned have;
76    z_streamp strm = &(state->strm);
77
78    /* allocate memory if this is the first time through */
79    if (state->size == 0 && gz_init(state) == -1)
80        return -1;
81
82    /* write directly if requested */
83    if (state->direct) {
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());
87            return -1;
88        }
89        strm->avail_in = 0;
90        return 0;
91    }
92
93    /* run deflate() on provided input until it produces no more output */
94    ret = Z_OK;
95    do {
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());
104                return -1;
105            }
106            if (strm->avail_out == 0) {
107                strm->avail_out = state->size;
108                strm->next_out = state->out;
109            }
110            state->x.next = strm->next_out;
111        }
112
113        /* compress */
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");
119            return -1;
120        }
121        have -= strm->avail_out;
122    } while (have);
123
124    /* if that completed a deflate stream, allow another to start */
125    if (flush == Z_FINISH)
126        deflateReset(strm);
127
128    /* all done, no errors */
129    return 0;
130}
131
132/* Compress len zeros to output.  Return -1 on error, 0 on success. */
133local int gz_zero(state, len)
134    gz_statep state;
135    z_off64_t len;
136{
137    int first;
138    unsigned n;
139    z_streamp strm = &(state->strm);
140
141    /* consume whatever's left in the input buffer */
142    if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
143        return -1;
144
145    /* compress len zeros (len guaranteed > 0) */
146    first = 1;
147    while (len) {
148        n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
149            (unsigned)len : state->size;
150        if (first) {
151            memset(state->in, 0, n);
152            first = 0;
153        }
154        strm->avail_in = n;
155        strm->next_in = state->in;
156        state->x.pos += n;
157        if (gz_comp(state, Z_NO_FLUSH) == -1)
158            return -1;
159        len -= n;
160    }
161    return 0;
162}
163
164/* -- see zlib.h -- */
165int ZEXPORT gzwrite(file, buf, len)
166    gzFile file;
167    voidpc buf;
168    unsigned len;
169{
170    unsigned put = len;
171    gz_statep state;
172    z_streamp strm;
173
174    /* get internal structure */
175    if (file == NULL)
176        return 0;
177    state = (gz_statep)file;
178    strm = &(state->strm);
179
180    /* check that we're writing and that there's no error */
181    if (state->mode != GZ_WRITE || state->err != Z_OK)
182        return 0;
183
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) */
186    if ((int)len < 0) {
187        gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
188        return 0;
189    }
190
191    /* if len is zero, avoid unnecessary operations */
192    if (len == 0)
193        return 0;
194
195    /* allocate memory if this is the first time through */
196    if (state->size == 0 && gz_init(state) == -1)
197        return 0;
198
199    /* check for seek request */
200    if (state->seek) {
201        state->seek = 0;
202        if (gz_zero(state, state->skip) == -1)
203            return 0;
204    }
205
206    /* for small len, copy to input buffer, otherwise compress directly */
207    if (len < state->size) {
208        /* copy to input buffer, compress when full */
209        do {
210            unsigned have, copy;
211
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;
216            if (copy > len)
217                copy = len;
218            memcpy(state->in + have, buf, copy);
219            strm->avail_in += copy;
220            state->x.pos += copy;
221            buf = (const char *)buf + copy;
222            len -= copy;
223            if (len && gz_comp(state, Z_NO_FLUSH) == -1)
224                return 0;
225        } while (len);
226    }
227    else {
228        /* consume whatever's left in the input buffer */
229        if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
230            return 0;
231
232        /* directly compress user buffer to file */
233        strm->avail_in = len;
234        strm->next_in = (z_const Bytef *)buf;
235        state->x.pos += len;
236        if (gz_comp(state, Z_NO_FLUSH) == -1)
237            return 0;
238    }
239
240    /* input was all buffered or compressed (put will fit in int) */
241    return (int)put;
242}
243
244/* -- see zlib.h -- */
245int ZEXPORT gzputc(file, c)
246    gzFile file;
247    int c;
248{
249    unsigned have;
250    unsigned char buf[1];
251    gz_statep state;
252    z_streamp strm;
253
254    /* get internal structure */
255    if (file == NULL)
256        return -1;
257    state = (gz_statep)file;
258    strm = &(state->strm);
259
260    /* check that we're writing and that there's no error */
261    if (state->mode != GZ_WRITE || state->err != Z_OK)
262        return -1;
263
264    /* check for seek request */
265    if (state->seek) {
266        state->seek = 0;
267        if (gz_zero(state, state->skip) == -1)
268            return -1;
269    }
270
271    /* try writing to input buffer for speed (state->size == 0 if buffer not
272       initialized) */
273    if (state->size) {
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) {
278            state->in[have] = c;
279            strm->avail_in++;
280            state->x.pos++;
281            return c & 0xff;
282        }
283    }
284
285    /* no room in buffer or not initialized, use gz_write() */
286    buf[0] = c;
287    if (gzwrite(file, buf, 1) != 1)
288        return -1;
289    return c & 0xff;
290}
291
292/* -- see zlib.h -- */
293int ZEXPORT gzputs(file, str)
294    gzFile file;
295    const char *str;
296{
297    int ret;
298    unsigned len;
299
300    /* write string */
301    len = (unsigned)strlen(str);
302    ret = gzwrite(file, str, len);
303    return ret == 0 && len != 0 ? -1 : ret;
304}
305
306#if defined(STDC) || defined(Z_HAVE_STDARG_H)
307#include <stdarg.h>
308
309/* -- see zlib.h -- */
310int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
311{
312    int size, len;
313    gz_statep state;
314    z_streamp strm;
315
316    /* get internal structure */
317    if (file == NULL)
318        return -1;
319    state = (gz_statep)file;
320    strm = &(state->strm);
321
322    /* check that we're writing and that there's no error */
323    if (state->mode != GZ_WRITE || state->err != Z_OK)
324        return 0;
325
326    /* make sure we have some buffer space */
327    if (state->size == 0 && gz_init(state) == -1)
328        return 0;
329
330    /* check for seek request */
331    if (state->seek) {
332        state->seek = 0;
333        if (gz_zero(state, state->skip) == -1)
334            return 0;
335    }
336
337    /* consume whatever's left in the input buffer */
338    if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
339        return 0;
340
341    /* do the printf() into the input buffer, put length in len */
342    size = (int)(state->size);
343    state->in[size - 1] = 0;
344#ifdef NO_vsnprintf
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;
349#  else
350    len = vsprintf((char *)(state->in), format, va);
351#  endif
352#else
353#  ifdef HAS_vsnprintf_void
354    (void)vsnprintf((char *)(state->in), size, format, va);
355    len = strlen((char *)(state->in));
356#  else
357    len = vsnprintf((char *)(state->in), size, format, va);
358#  endif
359#endif
360
361    /* check that printf() results fit in buffer */
362    if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
363        return 0;
364
365    /* update buffer and position, defer compression until needed */
366    strm->avail_in = (unsigned)len;
367    strm->next_in = state->in;
368    state->x.pos += len;
369    return len;
370}
371
372int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
373{
374    va_list va;
375    int ret;
376
377    va_start(va, format);
378    ret = gzvprintf(file, format, va);
379    va_end(va);
380    return ret;
381}
382
383#else /* !STDC && !Z_HAVE_STDARG_H */
384
385/* -- see zlib.h -- */
386int 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)
388    gzFile file;
389    const char *format;
390    int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
391        a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
392{
393    int size, len;
394    gz_statep state;
395    z_streamp strm;
396
397    /* get internal structure */
398    if (file == NULL)
399        return -1;
400    state = (gz_statep)file;
401    strm = &(state->strm);
402
403    /* check that can really pass pointer in ints */
404    if (sizeof(int) != sizeof(void *))
405        return 0;
406
407    /* check that we're writing and that there's no error */
408    if (state->mode != GZ_WRITE || state->err != Z_OK)
409        return 0;
410
411    /* make sure we have some buffer space */
412    if (state->size == 0 && gz_init(state) == -1)
413        return 0;
414
415    /* check for seek request */
416    if (state->seek) {
417        state->seek = 0;
418        if (gz_zero(state, state->skip) == -1)
419            return 0;
420    }
421
422    /* consume whatever's left in the input buffer */
423    if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
424        return 0;
425
426    /* do the printf() into the input buffer, put length in len */
427    size = (int)(state->size);
428    state->in[size - 1] = 0;
429#ifdef NO_snprintf
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;
435#  else
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);
438#  endif
439#else
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));
444#  else
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,
447                   a19, a20);
448#  endif
449#endif
450
451    /* check that printf() results fit in buffer */
452    if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
453        return 0;
454
455    /* update buffer and position, defer compression until needed */
456    strm->avail_in = (unsigned)len;
457    strm->next_in = state->in;
458    state->x.pos += len;
459    return len;
460}
461
462#endif
463
464/* -- see zlib.h -- */
465int ZEXPORT gzflush(file, flush)
466    gzFile file;
467    int flush;
468{
469    gz_statep state;
470
471    /* get internal structure */
472    if (file == NULL)
473        return -1;
474    state = (gz_statep)file;
475
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;
479
480    /* check flush parameter */
481    if (flush < 0 || flush > Z_FINISH)
482        return Z_STREAM_ERROR;
483
484    /* check for seek request */
485    if (state->seek) {
486        state->seek = 0;
487        if (gz_zero(state, state->skip) == -1)
488            return -1;
489    }
490
491    /* compress remaining data with requested flush */
492    gz_comp(state, flush);
493    return state->err;
494}
495
496/* -- see zlib.h -- */
497int ZEXPORT gzsetparams(file, level, strategy)
498    gzFile file;
499    int level;
500    int strategy;
501{
502    gz_statep state;
503    z_streamp strm;
504
505    /* get internal structure */
506    if (file == NULL)
507        return Z_STREAM_ERROR;
508    state = (gz_statep)file;
509    strm = &(state->strm);
510
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;
514
515    /* if no change is requested, then do nothing */
516    if (level == state->level && strategy == state->strategy)
517        return Z_OK;
518
519    /* check for seek request */
520    if (state->seek) {
521        state->seek = 0;
522        if (gz_zero(state, state->skip) == -1)
523            return -1;
524    }
525
526    /* change compression parameters for subsequent input */
527    if (state->size) {
528        /* flush previous input with previous parameters before changing */
529        if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1)
530            return state->err;
531        deflateParams(strm, level, strategy);
532    }
533    state->level = level;
534    state->strategy = strategy;
535    return Z_OK;
536}
537
538/* -- see zlib.h -- */
539int ZEXPORT gzclose_w(file)
540    gzFile file;
541{
542    int ret = Z_OK;
543    gz_statep state;
544
545    /* get internal structure */
546    if (file == NULL)
547        return Z_STREAM_ERROR;
548    state = (gz_statep)file;
549
550    /* check that we're writing */
551    if (state->mode != GZ_WRITE)
552        return Z_STREAM_ERROR;
553
554    /* check for seek request */
555    if (state->seek) {
556        state->seek = 0;
557        if (gz_zero(state, state->skip) == -1)
558            ret = state->err;
559    }
560
561    /* flush, free memory, and close file */
562    if (gz_comp(state, Z_FINISH) == -1)
563        ret = state->err;
564    if (state->size) {
565        if (!state->direct) {
566            (void)deflateEnd(&(state->strm));
567            free(state->out);
568        }
569        free(state->in);
570    }
571    gz_error(state, Z_OK, NULL);
572    free(state->path);
573    if (close(state->fd) == -1)
574        ret = Z_ERRNO;
575    free(state);
576    return ret;
577}
578