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/* gzwrite.c -- zlib functions for writing gzip files
* Copyright (C) 2004, 2005, 2010 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));
/* Initialize state for writing a gzip file. Mark initialization by setting
state->size to non-zero. Return -1 on failure or 0 on success. */
local int gz_init(state)
gz_statep state;
{
int ret;
z_streamp strm = &(state->strm);
/* allocate input and output buffers */
state->in = malloc(state->want);
state->out = malloc(state->want);
if (state->in == NULL || state->out == NULL) {
if (state->out != NULL)
free(state->out);
if (state->in != 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,
15 + 16, 8, state->strategy);
if (ret != Z_OK) {
free(state->in);
gz_error(state, Z_MEM_ERROR, "out of memory");
return -1;
}
/* mark state as initialized */
state->size = state->want;
/* initialize write buffer */
strm->avail_out = state->size;
strm->next_out = state->out;
state->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, 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. */
local int gz_comp(state, flush)
gz_statep state;
int flush;
{
int ret, got;
unsigned have;
z_streamp strm = &(state->strm);
/* allocate memory if this is the first time through */
if (state->size == 0 && gz_init(state) == -1)
return -1;
/* 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))) {
have = (unsigned)(strm->next_out - state->next);
if (have && ((got = write(state->fd, state->next, have)) < 0 ||
(unsigned)got != have)) {
gz_error(state, Z_ERRNO, zstrerror());
return -1;
}
if (strm->avail_out == 0) {
strm->avail_out = state->size;
strm->next_out = state->out;
}
state->next = strm->next_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 error, 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->pos += n;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return -1;
len -= n;
}
return 0;
}
/* -- see zlib.h -- */
int ZEXPORT gzwrite(file, buf, len)
gzFile file;
voidpc buf;
unsigned len;
{
unsigned put = len;
unsigned n;
gz_statep state;
z_streamp strm;
/* get internal structure */
if (file == NULL)
return 0;
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 0;
/* since an int is returned, make sure len fits in one, otherwise return
with an error (this avoids the flaw in the interface) */
if ((int)len < 0) {
gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");
return 0;
}
/* 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 {
if (strm->avail_in == 0)
strm->next_in = state->in;
n = state->size - strm->avail_in;
if (n > len)
n = len;
memcpy(strm->next_in + strm->avail_in, buf, n);
strm->avail_in += n;
state->pos += n;
buf = (char *)buf + n;
len -= n;
if (len && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
} while (len);
}
else {
/* consume whatever's left in the input buffer */
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
/* directly compress user buffer to file */
strm->avail_in = len;
strm->next_in = (voidp)buf;
state->pos += len;
if (gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
}
/* input was all buffered or compressed (put will fit in int) */
return (int)put;
}
/* -- see zlib.h -- */
int ZEXPORT gzputc(file, c)
gzFile file;
int c;
{
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 (strm->avail_in < state->size) {
if (strm->avail_in == 0)
strm->next_in = state->in;
strm->next_in[strm->avail_in++] = c;
state->pos++;
return c;
}
/* no room in buffer or not initialized, use gz_write() */
buf[0] = c;
if (gzwrite(file, buf, 1) != 1)
return -1;
return c;
}
/* -- see zlib.h -- */
int ZEXPORT gzputs(file, str)
gzFile file;
const char *str;
{
int ret;
unsigned len;
/* write string */
len = (unsigned)strlen(str);
ret = gzwrite(file, str, len);
return ret == 0 && len != 0 ? -1 : ret;
}
#ifdef STDC
#include <stdarg.h>
/* -- see zlib.h -- */
int ZEXPORTVA gzprintf (gzFile file, const char *format, ...)
{
int size, len;
gz_statep state;
z_streamp strm;
va_list va;
/* 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 0;
/* make sure we have some buffer space */
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;
}
/* consume whatever's left in the input buffer */
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
/* do the printf() into the input buffer, put length in len */
size = (int)(state->size);
state->in[size - 1] = 0;
va_start(va, format);
#ifdef NO_vsnprintf
# ifdef HAS_vsprintf_void
(void)vsprintf(state->in, format, va);
va_end(va);
for (len = 0; len < state->in; len++)
if (state->in[len] == 0) break;
# else
len = vsprintf(state->in, format, va);
va_end(va);
# endif
#else
# ifdef HAS_vsnprintf_void
(void)vsnprintf(state->in, size, format, va);
va_end(va);
len = strlen(state->in);
# else
len = vsnprintf((char *)(state->in), size, format, va);
va_end(va);
# endif
#endif
/* check that printf() results fit in buffer */
if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
return 0;
/* update buffer and position, defer compression until needed */
strm->avail_in = (unsigned)len;
strm->next_in = state->in;
state->pos += len;
return len;
}
#else /* !STDC */
/* -- 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;
{
int size, len;
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 0;
/* make sure we have some buffer space */
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;
}
/* consume whatever's left in the input buffer */
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
return 0;
/* do the printf() into the input buffer, put length in len */
size = (int)(state->size);
state->in[size - 1] = 0;
#ifdef NO_snprintf
# ifdef HAS_sprintf_void
sprintf(state->in, 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 (state->in[len] == 0) break;
# else
len = sprintf(state->in, 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(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
len = strlen(state->in);
# else
len = snprintf(state->in, 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 >= (int)size || state->in[size - 1] != 0)
return 0;
/* update buffer and position, defer compression until needed */
strm->avail_in = (unsigned)len;
strm->next_in = state->in;
state->pos += len;
return len;
}
#endif
/* -- see zlib.h -- */
int ZEXPORT gzflush(file, flush)
gzFile file;
int flush;
{
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 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 -1;
}
/* compress remaining data with requested flush */
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 -1;
}
/* 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_PARTIAL_FLUSH) == -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 = 0;
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;
ret += gz_zero(state, state->skip);
}
/* flush, free memory, and close file */
ret += gz_comp(state, Z_FINISH);
(void)deflateEnd(&(state->strm));
free(state->out);
free(state->in);
gz_error(state, Z_OK, NULL);
free(state->path);
ret += close(state->fd);
free(state);
return ret ? Z_ERRNO : Z_OK;
}
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