1/* gzwrite.c -- zlib functions for writing gzip files
2 * Copyright (C) 2004, 2005, 2010, 2011, 2012 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 = 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 = 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    unsigned n;
172    gz_statep state;
173    z_streamp strm;
174
175    /* get internal structure */
176    if (file == NULL)
177        return 0;
178    state = (gz_statep)file;
179    strm = &(state->strm);
180
181    /* check that we're writing and that there's no error */
182    if (state->mode != GZ_WRITE || state->err != Z_OK)
183        return 0;
184
185    /* since an int is returned, make sure len fits in one, otherwise return
186       with an error (this avoids the flaw in the interface) */
187    if ((int)len < 0) {
188        gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
189        return 0;
190    }
191
192    /* if len is zero, avoid unnecessary operations */
193    if (len == 0)
194        return 0;
195
196    /* allocate memory if this is the first time through */
197    if (state->size == 0 && gz_init(state) == -1)
198        return 0;
199
200    /* check for seek request */
201    if (state->seek) {
202        state->seek = 0;
203        if (gz_zero(state, state->skip) == -1)
204            return 0;
205    }
206
207    /* for small len, copy to input buffer, otherwise compress directly */
208    if (len < state->size) {
209        /* copy to input buffer, compress when full */
210        do {
211            if (strm->avail_in == 0)
212                strm->next_in = state->in;
213            n = state->size - strm->avail_in;
214            if (n > len)
215                n = len;
216            memcpy(strm->next_in + strm->avail_in, buf, n);
217            strm->avail_in += n;
218            state->x.pos += n;
219            buf = (char *)buf + n;
220            len -= n;
221            if (len && gz_comp(state, Z_NO_FLUSH) == -1)
222                return 0;
223        } while (len);
224    }
225    else {
226        /* consume whatever's left in the input buffer */
227        if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
228            return 0;
229
230        /* directly compress user buffer to file */
231        strm->avail_in = len;
232        strm->next_in = (voidp)buf;
233        state->x.pos += len;
234        if (gz_comp(state, Z_NO_FLUSH) == -1)
235            return 0;
236    }
237
238    /* input was all buffered or compressed (put will fit in int) */
239    return (int)put;
240}
241
242/* -- see zlib.h -- */
243int ZEXPORT gzputc(file, c)
244    gzFile file;
245    int c;
246{
247    unsigned char buf[1];
248    gz_statep state;
249    z_streamp strm;
250
251    /* get internal structure */
252    if (file == NULL)
253        return -1;
254    state = (gz_statep)file;
255    strm = &(state->strm);
256
257    /* check that we're writing and that there's no error */
258    if (state->mode != GZ_WRITE || state->err != Z_OK)
259        return -1;
260
261    /* check for seek request */
262    if (state->seek) {
263        state->seek = 0;
264        if (gz_zero(state, state->skip) == -1)
265            return -1;
266    }
267
268    /* try writing to input buffer for speed (state->size == 0 if buffer not
269       initialized) */
270    if (strm->avail_in < state->size) {
271        if (strm->avail_in == 0)
272            strm->next_in = state->in;
273        strm->next_in[strm->avail_in++] = c;
274        state->x.pos++;
275        return c & 0xff;
276    }
277
278    /* no room in buffer or not initialized, use gz_write() */
279    buf[0] = c;
280    if (gzwrite(file, buf, 1) != 1)
281        return -1;
282    return c & 0xff;
283}
284
285/* -- see zlib.h -- */
286int ZEXPORT gzputs(file, str)
287    gzFile file;
288    const char *str;
289{
290    int ret;
291    unsigned len;
292
293    /* write string */
294    len = (unsigned)strlen(str);
295    ret = gzwrite(file, str, len);
296    return ret == 0 && len != 0 ? -1 : ret;
297}
298
299#if defined(STDC) || defined(Z_HAVE_STDARG_H)
300#include <stdarg.h>
301
302/* -- see zlib.h -- */
303int ZEXPORTVA gzprintf (gzFile file, const char *format, ...)
304{
305    int size, len;
306    gz_statep state;
307    z_streamp strm;
308    va_list va;
309
310    /* get internal structure */
311    if (file == NULL)
312        return -1;
313    state = (gz_statep)file;
314    strm = &(state->strm);
315
316    /* check that we're writing and that there's no error */
317    if (state->mode != GZ_WRITE || state->err != Z_OK)
318        return 0;
319
320    /* make sure we have some buffer space */
321    if (state->size == 0 && gz_init(state) == -1)
322        return 0;
323
324    /* check for seek request */
325    if (state->seek) {
326        state->seek = 0;
327        if (gz_zero(state, state->skip) == -1)
328            return 0;
329    }
330
331    /* consume whatever's left in the input buffer */
332    if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
333        return 0;
334
335    /* do the printf() into the input buffer, put length in len */
336    size = (int)(state->size);
337    state->in[size - 1] = 0;
338    va_start(va, format);
339#ifdef NO_vsnprintf
340#  ifdef HAS_vsprintf_void
341    (void)vsprintf(state->in, format, va);
342    va_end(va);
343    for (len = 0; len < size; len++)
344        if (state->in[len] == 0) break;
345#  else
346    len = vsprintf(state->in, format, va);
347    va_end(va);
348#  endif
349#else
350#  ifdef HAS_vsnprintf_void
351    (void)vsnprintf(state->in, size, format, va);
352    va_end(va);
353    len = strlen(state->in);
354#  else
355    len = vsnprintf((char *)(state->in), size, format, va);
356    va_end(va);
357#  endif
358#endif
359
360    /* check that printf() results fit in buffer */
361    if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
362        return 0;
363
364    /* update buffer and position, defer compression until needed */
365    strm->avail_in = (unsigned)len;
366    strm->next_in = state->in;
367    state->x.pos += len;
368    return len;
369}
370
371#else /* !STDC && !Z_HAVE_STDARG_H */
372
373/* -- see zlib.h -- */
374int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
375                       a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
376    gzFile file;
377    const char *format;
378    int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
379        a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
380{
381    int size, len;
382    gz_statep state;
383    z_streamp strm;
384
385    /* get internal structure */
386    if (file == NULL)
387        return -1;
388    state = (gz_statep)file;
389    strm = &(state->strm);
390
391    /* check that can really pass pointer in ints */
392    if (sizeof(int) != sizeof(void *))
393        return 0;
394
395    /* check that we're writing and that there's no error */
396    if (state->mode != GZ_WRITE || state->err != Z_OK)
397        return 0;
398
399    /* make sure we have some buffer space */
400    if (state->size == 0 && gz_init(state) == -1)
401        return 0;
402
403    /* check for seek request */
404    if (state->seek) {
405        state->seek = 0;
406        if (gz_zero(state, state->skip) == -1)
407            return 0;
408    }
409
410    /* consume whatever's left in the input buffer */
411    if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
412        return 0;
413
414    /* do the printf() into the input buffer, put length in len */
415    size = (int)(state->size);
416    state->in[size - 1] = 0;
417#ifdef NO_snprintf
418#  ifdef HAS_sprintf_void
419    sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
420            a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
421    for (len = 0; len < size; len++)
422        if (state->in[len] == 0) break;
423#  else
424    len = sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
425                a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
426#  endif
427#else
428#  ifdef HAS_snprintf_void
429    snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
430             a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
431    len = strlen(state->in);
432#  else
433    len = snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
434                 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
435#  endif
436#endif
437
438    /* check that printf() results fit in buffer */
439    if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
440        return 0;
441
442    /* update buffer and position, defer compression until needed */
443    strm->avail_in = (unsigned)len;
444    strm->next_in = state->in;
445    state->x.pos += len;
446    return len;
447}
448
449#endif
450
451/* -- see zlib.h -- */
452int ZEXPORT gzflush(file, flush)
453    gzFile file;
454    int flush;
455{
456    gz_statep state;
457
458    /* get internal structure */
459    if (file == NULL)
460        return -1;
461    state = (gz_statep)file;
462
463    /* check that we're writing and that there's no error */
464    if (state->mode != GZ_WRITE || state->err != Z_OK)
465        return Z_STREAM_ERROR;
466
467    /* check flush parameter */
468    if (flush < 0 || flush > Z_FINISH)
469        return Z_STREAM_ERROR;
470
471    /* check for seek request */
472    if (state->seek) {
473        state->seek = 0;
474        if (gz_zero(state, state->skip) == -1)
475            return -1;
476    }
477
478    /* compress remaining data with requested flush */
479    gz_comp(state, flush);
480    return state->err;
481}
482
483/* -- see zlib.h -- */
484int ZEXPORT gzsetparams(file, level, strategy)
485    gzFile file;
486    int level;
487    int strategy;
488{
489    gz_statep state;
490    z_streamp strm;
491
492    /* get internal structure */
493    if (file == NULL)
494        return Z_STREAM_ERROR;
495    state = (gz_statep)file;
496    strm = &(state->strm);
497
498    /* check that we're writing and that there's no error */
499    if (state->mode != GZ_WRITE || state->err != Z_OK)
500        return Z_STREAM_ERROR;
501
502    /* if no change is requested, then do nothing */
503    if (level == state->level && strategy == state->strategy)
504        return Z_OK;
505
506    /* check for seek request */
507    if (state->seek) {
508        state->seek = 0;
509        if (gz_zero(state, state->skip) == -1)
510            return -1;
511    }
512
513    /* change compression parameters for subsequent input */
514    if (state->size) {
515        /* flush previous input with previous parameters before changing */
516        if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1)
517            return state->err;
518        deflateParams(strm, level, strategy);
519    }
520    state->level = level;
521    state->strategy = strategy;
522    return Z_OK;
523}
524
525/* -- see zlib.h -- */
526int ZEXPORT gzclose_w(file)
527    gzFile file;
528{
529    int ret = Z_OK;
530    gz_statep state;
531
532    /* get internal structure */
533    if (file == NULL)
534        return Z_STREAM_ERROR;
535    state = (gz_statep)file;
536
537    /* check that we're writing */
538    if (state->mode != GZ_WRITE)
539        return Z_STREAM_ERROR;
540
541    /* check for seek request */
542    if (state->seek) {
543        state->seek = 0;
544        if (gz_zero(state, state->skip) == -1)
545            ret = state->err;
546    }
547
548    /* flush, free memory, and close file */
549    if (gz_comp(state, Z_FINISH) == -1)
550        ret = state->err;
551    if (!state->direct) {
552        (void)deflateEnd(&(state->strm));
553        free(state->out);
554    }
555    free(state->in);
556    gz_error(state, Z_OK, NULL);
557    free(state->path);
558    if (close(state->fd) == -1)
559        ret = Z_ERRNO;
560    free(state);
561    return ret;
562}
563
564/* used by zlibVersion() to get the vsnprintf story from the horse's mouth */
565unsigned long ZEXPORT gzflags()
566{
567    unsigned long flags = 0;
568#if defined(STDC) || defined(Z_HAVE_STDARG_H)
569#  ifdef NO_vsnprintf
570    flags += 1L << 25;
571#    ifdef HAS_vsprintf_void
572    flags += 1L << 26;
573#    endif
574#  else
575#    ifdef HAS_vsnprintf_void
576    flags += 1L << 26;
577#    endif
578#  endif
579#else
580    flags += 1L << 24;
581#  ifdef NO_snprintf
582    flags += 1L << 25;
583#    ifdef HAS_sprintf_void
584    flags += 1L << 26;
585#    endif
586#  else
587#    ifdef HAS_snprintf_void
588    flags += 1L << 26;
589#    endif
590#  endif
591#endif
592    return flags;
593}
594