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gzwrite.c
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/* gzwrite.c -- zlib functions for writing gzip files
* Copyright (C) 2004-2017 Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "gzguts.h"
/* Local functions */
local int gz_init OF((gz_statep));
local int gz_comp OF((gz_statep, int));
local int gz_zero OF((gz_statep, z_off64_t));
local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));
/* Initialize state for writing a gzip file. Mark initialization by setting
state->size to non-zero. Return -1 on a memory allocation failure, or 0 on
success. */
local int gz_init(state)
gz_statep state;
{
int ret;
z_streamp strm = &(state->strm);
/* allocate input buffer (double size for gzprintf) */
state->in = (unsigned char *)malloc(state->want << 1);
if (state->in == NULL) {
gz_error(state, Z_MEM_ERROR, "out of memory");
return -1;
}
/* only need output buffer and deflate state if compressing */
if (!state->direct) {
/* allocate output buffer */
state->out = (unsigned char *)malloc(state->want);
if (state->out == NULL) {
free(state->in);
gz_error(state, Z_MEM_ERROR, "out of memory");
return -1;
}
/* allocate deflate memory, set up for gzip compression */
strm->zalloc = Z_NULL;
strm->zfree = Z_NULL;
strm->opaque = Z_NULL;
ret = deflateInit2(strm, state->level, Z_DEFLATED,
MAX_WBITS + 16, DEF_MEM_LEVEL, state->strategy);
if (ret != Z_OK) {
free(state->out);
free(state->in);
gz_error(state, Z_MEM_ERROR, "out of memory");
return -1;
}
strm->next_in = NULL;
}
/* mark state as initialized */
state->size = state->want;
/* initialize write buffer if compressing */
if (!state->direct) {
strm->avail_out = state->size;
strm->next_out = state->out;
state->x.next = strm->next_out;
}
return 0;
}
/* Compress whatever is at avail_in and next_in and write to the output file.
Return -1 if there is an error writing to the output file or if gz_init()
fails to allocate memory, otherwise 0. flush is assumed to be a valid
deflate() flush value. If flush is Z_FINISH, then the deflate() state is
reset to start a new gzip stream. If gz->direct is true, then simply write
to the output file without compressing, and ignore flush. */
local int gz_comp(state, flush)
gz_statep state;
int flush;
{
int ret, writ;
unsigned have, put, max = ((unsigned)-1 >> 2) + 1;
z_streamp strm = &(state->strm);
/* allocate memory if this is the first time through */
if (state->size == 0 && gz_init(state) == -1)
return -1;
/* write directly if requested */
if (state->direct) {
while (strm->avail_in) {
put = strm->avail_in > max ? max : strm->avail_in;
writ = write(state->fd, strm->next_in, put);
if (writ < 0) {
gz_error(state, Z_ERRNO, zstrerror());
return -1;
}
strm->avail_in -= (unsigned)writ;
strm->next_in += writ;
}
return 0;
}
/* run deflate() on provided input until it produces no more output */
ret = Z_OK;
do {
/* write out current buffer contents if full, or if flushing, but if
doing Z_FINISH then don't write until we get to Z_STREAM_END */
if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
(flush != Z_FINISH || ret == Z_STREAM_END))) {
while (strm->next_out > state->x.next) {
put = strm->next_out - state->x.next > (int)max ? max :
(unsigned)(strm->next_out - state->x.next);
writ = write(state->fd, state->x.next, put);
if (writ < 0) {
gz_error(state, Z_ERRNO, zstrerror());
return -1;
}
state->x.next += writ;
}
if (strm->avail_out == 0) {
strm->avail_out = state->size;
strm->next_out = state->out;
state->x.next = state->out;
}
}
/* compress */
have = strm->avail_out;
ret = deflate(strm, flush);
if (ret == Z_STREAM_ERROR) {
gz_error(state, Z_STREAM_ERROR,
"internal error: deflate stream corrupt");
return -1;
}
have -= strm->avail_out;
} while (have);
/* if that completed a deflate stream, allow another to start */
if (flush == Z_FINISH)
deflateReset(strm);
/* all done, no errors */
return 0;
}
/* Compress len zeros to output. Return -1 on a write error or memory
allocation failure by gz_comp(), or 0 on success. */
local int gz_zero(state, len)
gz_statep state;
z_off64_t len;
{
int first;
unsigned n;
z_streamp strm = &(state->strm);
/* consume whatever's left in the input buffer */
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
return -1;
/* compress len zeros (len guaranteed > 0) */
first = 1;
while (len) {
n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
(unsigned)len : state->size;
if (first) {
memset(state->in, 0, n);
first = 0;
}
strm->avail_in = n;
strm->next_in = state->in;
state->x.pos += n;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return -1;
len -= n;
}
return 0;
}
/* Write len bytes from buf to file. Return the number of bytes written. If
the returned value is less than len, then there was an error. */
local z_size_t gz_write(state, buf, len)
gz_statep state;
voidpc buf;
z_size_t len;
{
z_size_t put = len;
/* if len is zero, avoid unnecessary operations */
if (len == 0)
return 0;
/* allocate memory if this is the first time through */
if (state->size == 0 && gz_init(state) == -1)
return 0;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return 0;
}
/* for small len, copy to input buffer, otherwise compress directly */
if (len < state->size) {
/* copy to input buffer, compress when full */
do {
unsigned have, copy;
if (state->strm.avail_in == 0)
state->strm.next_in = state->in;
have = (unsigned)((state->strm.next_in + state->strm.avail_in) -
state->in);
copy = state->size - have;
if (copy > len)
copy = len;
memcpy(state->in + have, buf, copy);
state->strm.avail_in += copy;
state->x.pos += copy;
buf = (const char *)buf + copy;
len -= copy;
if (len && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
} while (len);
}
else {
/* consume whatever's left in the input buffer */
if (state->strm.avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
/* directly compress user buffer to file */
state->strm.next_in = (z_const Bytef *)buf;
do {
unsigned n = (unsigned)-1;
if (n > len)
n = len;
state->strm.avail_in = n;
state->x.pos += n;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
len -= n;
} while (len);
}
/* input was all buffered or compressed */
return put;
}
/* -- see zlib.h -- */
int ZEXPORT gzwrite(file, buf, len)
gzFile file;
voidpc buf;
unsigned len;
{
gz_statep state;
/* get internal structure */
if (file == NULL)
return 0;
state = (gz_statep)file;
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return 0;
/* since an int is returned, make sure len fits in one, otherwise return
with an error (this avoids a flaw in the interface) */
if ((int)len < 0) {
gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
return 0;
}
/* write len bytes from buf (the return value will fit in an int) */
return (int)gz_write(state, buf, len);
}
/* -- see zlib.h -- */
z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
voidpc buf;
z_size_t size;
z_size_t nitems;
gzFile file;
{
z_size_t len;
gz_statep state;
/* get internal structure */
if (file == NULL)
return 0;
state = (gz_statep)file;
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return 0;
/* compute bytes to read -- error on overflow */
len = nitems * size;
if (size && len / size != nitems) {
gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
return 0;
}
/* write len bytes to buf, return the number of full items written */
return len ? gz_write(state, buf, len) / size : 0;
}
/* -- see zlib.h -- */
int ZEXPORT gzputc(file, c)
gzFile file;
int c;
{
unsigned have;
unsigned char buf[1];
gz_statep state;
z_streamp strm;
/* get internal structure */
if (file == NULL)
return -1;
state = (gz_statep)file;
strm = &(state->strm);
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return -1;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return -1;
}
/* try writing to input buffer for speed (state->size == 0 if buffer not
initialized) */
if (state->size) {
if (strm->avail_in == 0)
strm->next_in = state->in;
have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
if (have < state->size) {
state->in[have] = (unsigned char)c;
strm->avail_in++;
state->x.pos++;
return c & 0xff;
}
}
/* no room in buffer or not initialized, use gz_write() */
buf[0] = (unsigned char)c;
if (gz_write(state, buf, 1) != 1)
return -1;
return c & 0xff;
}
/* -- see zlib.h -- */
int ZEXPORT gzputs(file, str)
gzFile file;
const char *str;
{
int ret;
z_size_t len;
gz_statep state;
/* get internal structure */
if (file == NULL)
return -1;
state = (gz_statep)file;
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return -1;
/* write string */
len = strlen(str);
ret = gz_write(state, str, len);
return ret == 0 && len != 0 ? -1 : ret;
}
#if defined(STDC) || defined(Z_HAVE_STDARG_H)
#include <stdarg.h>
/* -- see zlib.h -- */
int ZEXPORTVA gzvprintf(gzFile file, const char *format, va_list va)
{
int len;
unsigned left;
char *next;
gz_statep state;
z_streamp strm;
/* get internal structure */
if (file == NULL)
return Z_STREAM_ERROR;
state = (gz_statep)file;
strm = &(state->strm);
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return Z_STREAM_ERROR;
/* make sure we have some buffer space */
if (state->size == 0 && gz_init(state) == -1)
return state->err;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return state->err;
}
/* do the printf() into the input buffer, put length in len -- the input
buffer is double-sized just for this function, so there is guaranteed to
be state->size bytes available after the current contents */
if (strm->avail_in == 0)
strm->next_in = state->in;
next = (char *)(state->in + (strm->next_in - state->in) + strm->avail_in);
next[state->size - 1] = 0;
#ifdef NO_vsnprintf
# ifdef HAS_vsprintf_void
(void)vsprintf(next, format, va);
for (len = 0; len < state->size; len++)
if (next[len] == 0) break;
# else
len = vsprintf(next, format, va);
# endif
#else
# ifdef HAS_vsnprintf_void
(void)vsnprintf(next, state->size, format, va);
len = strlen(next);
# else
len = vsnprintf(next, state->size, format, va);
# endif
#endif
/* check that printf() results fit in buffer */
if (len == 0 || (unsigned)len >= state->size || next[state->size - 1] != 0)
return 0;
/* update buffer and position, compress first half if past that */
strm->avail_in += (unsigned)len;
state->x.pos += len;
if (strm->avail_in >= state->size) {
left = strm->avail_in - state->size;
strm->avail_in = state->size;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return state->err;
memcpy(state->in, state->in + state->size, left);
strm->next_in = state->in;
strm->avail_in = left;
}
return len;
}
int ZEXPORTVA gzprintf(gzFile file, const char *format, ...)
{
va_list va;
int ret;
va_start(va, format);
ret = gzvprintf(file, format, va);
va_end(va);
return ret;
}
#else /* !STDC && !Z_HAVE_STDARG_H */
/* -- see zlib.h -- */
int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
gzFile file;
const char *format;
int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
{
unsigned len, left;
char *next;
gz_statep state;
z_streamp strm;
/* get internal structure */
if (file == NULL)
return Z_STREAM_ERROR;
state = (gz_statep)file;
strm = &(state->strm);
/* check that can really pass pointer in ints */
if (sizeof(int) != sizeof(void *))
return Z_STREAM_ERROR;
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return Z_STREAM_ERROR;
/* make sure we have some buffer space */
if (state->size == 0 && gz_init(state) == -1)
return state->error;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return state->error;
}
/* do the printf() into the input buffer, put length in len -- the input
buffer is double-sized just for this function, so there is guaranteed to
be state->size bytes available after the current contents */
if (strm->avail_in == 0)
strm->next_in = state->in;
next = (char *)(strm->next_in + strm->avail_in);
next[state->size - 1] = 0;
#ifdef NO_snprintf
# ifdef HAS_sprintf_void
sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
a13, a14, a15, a16, a17, a18, a19, a20);
for (len = 0; len < size; len++)
if (next[len] == 0)
break;
# else
len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
a12, a13, a14, a15, a16, a17, a18, a19, a20);
# endif
#else
# ifdef HAS_snprintf_void
snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
len = strlen(next);
# else
len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8,
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
# endif
#endif
/* check that printf() results fit in buffer */
if (len == 0 || len >= state->size || next[state->size - 1] != 0)
return 0;
/* update buffer and position, compress first half if past that */
strm->avail_in += len;
state->x.pos += len;
if (strm->avail_in >= state->size) {
left = strm->avail_in - state->size;
strm->avail_in = state->size;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return state->err;
memcpy(state->in, state->in + state->size, left);
strm->next_in = state->in;
strm->avail_in = left;
}
return (int)len;
}
#endif
/* -- see zlib.h -- */
int ZEXPORT gzflush(file, flush)
gzFile file;
int flush;
{
gz_statep state;
/* get internal structure */
if (file == NULL)
return Z_STREAM_ERROR;
state = (gz_statep)file;
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return Z_STREAM_ERROR;
/* check flush parameter */
if (flush < 0 || flush > Z_FINISH)
return Z_STREAM_ERROR;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return state->err;
}
/* compress remaining data with requested flush */
(void)gz_comp(state, flush);
return state->err;
}
/* -- see zlib.h -- */
int ZEXPORT gzsetparams(file, level, strategy)
gzFile file;
int level;
int strategy;
{
gz_statep state;
z_streamp strm;
/* get internal structure */
if (file == NULL)
return Z_STREAM_ERROR;
state = (gz_statep)file;
strm = &(state->strm);
/* check that we're writing and that there's no error */
if (state->mode != GZ_WRITE || state->err != Z_OK)
return Z_STREAM_ERROR;
/* if no change is requested, then do nothing */
if (level == state->level && strategy == state->strategy)
return Z_OK;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
return state->err;
}
/* change compression parameters for subsequent input */
if (state->size) {
/* flush previous input with previous parameters before changing */
if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
return state->err;
deflateParams(strm, level, strategy);
}
state->level = level;
state->strategy = strategy;
return Z_OK;
}
/* -- see zlib.h -- */
int ZEXPORT gzclose_w(file)
gzFile file;
{
int ret = Z_OK;
gz_statep state;
/* get internal structure */
if (file == NULL)
return Z_STREAM_ERROR;
state = (gz_statep)file;
/* check that we're writing */
if (state->mode != GZ_WRITE)
return Z_STREAM_ERROR;
/* check for seek request */
if (state->seek) {
state->seek = 0;
if (gz_zero(state, state->skip) == -1)
ret = state->err;
}
/* flush, free memory, and close file */
if (gz_comp(state, Z_FINISH) == -1)
ret = state->err;
if (state->size) {
if (!state->direct) {
(void)deflateEnd(&(state->strm));
free(state->out);
}
free(state->in);
}
gz_error(state, Z_OK, NULL);
free(state->path);
if (close(state->fd) == -1)
ret = Z_ERRNO;
free(state);
return ret;
}
deflateReset
int ZEXPORT deflateReset(z_streamp strm)
Definition: deflate.c:505
deflateParams
int ZEXPORT deflateParams(z_streamp strm, int level, int strategy)
Definition: deflate.c:568
deflateEnd
int ZEXPORT deflateEnd(z_streamp strm)
Definition: deflate.c:1076
deflate
int ZEXPORT deflate(z_streamp strm, int flush)
Definition: deflate.c:763
gzguts.h
local
#define local
Definition: gzguts.h:114
gz_statep
gz_state FAR * gz_statep
Definition: gzguts.h:202
DEF_MEM_LEVEL
#define DEF_MEM_LEVEL
Definition: gzguts.h:149
GZ_WRITE
#define GZ_WRITE
Definition: gzguts.h:161
GT_OFF
#define GT_OFF(x)
Definition: gzguts.h:217
zstrerror
#define zstrerror()
Definition: gzguts.h:133
gz_error
void ZLIB_INTERNAL gz_error(gz_statep state, int err, const char *msg)
Definition: gzlib.c:579
gzsetparams
int ZEXPORT gzsetparams(gzFile file, int level, int strategy)
Definition: gzwrite.c:585
gzprintf
int ZEXPORTVA gzprintf(gzFile file, const char *format, int a1, int a2, int a3, int a4, int a5, int a6, int a7, int a8, int a9, int a10, int a11, int a12, int a13, int a14, int a15, int a16, int a17, int a18, int a19, int a20)
Definition: gzwrite.c:465
gzputs
int ZEXPORT gzputs(gzFile file, const char *str)
Definition: gzwrite.c:352
gzputc
int ZEXPORT gzputc(gzFile file, int c)
Definition: gzwrite.c:304
gz_comp
int gz_comp(gz_statep state, int flush)
Definition: gzwrite.c:73
gzflush
int ZEXPORT gzflush(gzFile file, int flush)
Definition: gzwrite.c:553
gzclose_w
int ZEXPORT gzclose_w(gzFile file)
Definition: gzwrite.c:627
gzwrite
int ZEXPORT gzwrite(gzFile file, voidpc buf, unsigned len)
Definition: gzwrite.c:246
gz_write
z_size_t gz_write(gz_statep state, voidpc buf, z_size_t len)
Definition: gzwrite.c:178
gzfwrite
z_size_t ZEXPORT gzfwrite(voidpc buf, z_size_t size, z_size_t nitems, gzFile file)
Definition: gzwrite.c:274
gz_init
int gz_init(gz_statep state)
Definition: gzwrite.c:17
gz_zero
int gz_zero(gz_statep state, z_off64_t len)
Definition: gzwrite.c:145
gzFile_s
Definition: zlib.h:1817
gzFile_s::pos
z_off64_t pos
Definition: zlib.h:1820
ZEXPORT
#define ZEXPORT
Definition: zconf.h:380
voidpc
Byte const * voidpc
Definition: zconf.h:412
z_const
#define z_const
Definition: zconf.h:237
OF
#define OF(args)
Definition: zconf.h:292
z_off64_t
#define z_off64_t
Definition: zconf.h:513
MAX_WBITS
#define MAX_WBITS
Definition: zconf.h:270
z_size_t
unsigned long z_size_t
Definition: zconf.h:250
Bytef
Byte FAR Bytef
Definition: zconf.h:400
ZEXPORTVA
#define ZEXPORTVA
Definition: zconf.h:383
Z_DEFLATED
#define Z_DEFLATED
Definition: zlib.h:209
Z_ERRNO
#define Z_ERRNO
Definition: zlib.h:180
deflateInit2
#define deflateInit2(strm, level, method, windowBits, memLevel, strategy)
Definition: zlib.h:1797
z_streamp
z_stream FAR * z_streamp
Definition: zlib.h:108
Z_BLOCK
#define Z_BLOCK
Definition: zlib.h:173
Z_STREAM_END
#define Z_STREAM_END
Definition: zlib.h:178
Z_FINISH
#define Z_FINISH
Definition: zlib.h:172
Z_OK
#define Z_OK
Definition: zlib.h:177
Z_DATA_ERROR
#define Z_DATA_ERROR
Definition: zlib.h:182
Z_STREAM_ERROR
#define Z_STREAM_ERROR
Definition: zlib.h:181
Z_NO_FLUSH
#define Z_NO_FLUSH
Definition: zlib.h:168
Z_NULL
#define Z_NULL
Definition: zlib.h:212
Z_MEM_ERROR
#define Z_MEM_ERROR
Definition: zlib.h:183