6947bfe5ec
by the red-black tree which shall consolidate files with identical source object. Discovered and repaired a flaw in transitivity of iso_stream_cmp_ino().
833 lines
20 KiB
C
833 lines
20 KiB
C
/*
|
|
* Copyright (c) 2009 - 2011 Thomas Schmitt
|
|
*
|
|
* This file is part of the libisofs project; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License version 2
|
|
* or later as published by the Free Software Foundation.
|
|
* See COPYING file for details.
|
|
*
|
|
* It implements a filter facility which can pipe a IsoStream into gzip
|
|
* compression resp. uncompression, read its output and forward it as IsoStream
|
|
* output to an IsoFile.
|
|
* The gzip compression is done via zlib by Jean-loup Gailly and Mark Adler
|
|
* who state in <zlib.h>:
|
|
* "The data format used by the zlib library is described by RFCs (Request for
|
|
* Comments) 1950 to 1952 in the files http://www.ietf.org/rfc/rfc1950.txt
|
|
* (zlib format), rfc1951.txt (deflate format) and rfc1952.txt (gzip format)."
|
|
*
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "../config.h"
|
|
#endif
|
|
|
|
#include "../libisofs.h"
|
|
#include "../filter.h"
|
|
#include "../fsource.h"
|
|
#include "../util.h"
|
|
#include "../stream.h"
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/time.h>
|
|
#include <sys/wait.h>
|
|
#include <unistd.h>
|
|
#include <stdio.h>
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
#include <zlib.h>
|
|
#else
|
|
/* If zlib is not available then this code is a dummy */
|
|
#endif
|
|
|
|
|
|
/*
|
|
* A filter that encodes or decodes the content of gzip compressed files.
|
|
*/
|
|
|
|
|
|
/* --------------------------- GzipFilterRuntime ------------------------- */
|
|
|
|
|
|
/* Individual runtime properties exist only as long as the stream is opened.
|
|
*/
|
|
typedef struct
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
z_stream strm; /* The zlib processing context */
|
|
|
|
#endif
|
|
|
|
char *in_buffer;
|
|
char *out_buffer;
|
|
int in_buffer_size;
|
|
int out_buffer_size;
|
|
char *rpt; /* out_buffer + read_bytes */
|
|
|
|
off_t in_counter;
|
|
off_t out_counter;
|
|
|
|
int do_flush; /* flush mode for deflate() changes at end of input */
|
|
|
|
int error_ret;
|
|
|
|
} GzipFilterRuntime;
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
static
|
|
int gzip_running_destroy(GzipFilterRuntime **running, int flag)
|
|
{
|
|
GzipFilterRuntime *o= *running;
|
|
if (o == NULL)
|
|
return 0;
|
|
if (o->in_buffer != NULL)
|
|
free(o->in_buffer);
|
|
if (o->out_buffer != NULL)
|
|
free(o->out_buffer);
|
|
free((char *) o);
|
|
*running = NULL;
|
|
return 1;
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_running_new(GzipFilterRuntime **running, int flag)
|
|
{
|
|
GzipFilterRuntime *o;
|
|
|
|
*running = o = calloc(sizeof(GzipFilterRuntime), 1);
|
|
if (o == NULL) {
|
|
return ISO_OUT_OF_MEM;
|
|
}
|
|
memset(&(o->strm), 0, sizeof(o->strm));
|
|
o->in_buffer = NULL;
|
|
o->out_buffer = NULL;
|
|
o->in_buffer_size = 0;
|
|
o->out_buffer_size = 0;
|
|
o->rpt = NULL;
|
|
o->in_counter = 0;
|
|
o->out_counter = 0;
|
|
o->do_flush = Z_NO_FLUSH;
|
|
o->error_ret = 1;
|
|
|
|
o->in_buffer_size= 2048;
|
|
o->out_buffer_size= 2048;
|
|
o->in_buffer = calloc(o->in_buffer_size, 1);
|
|
o->out_buffer = calloc(o->out_buffer_size, 1);
|
|
if (o->in_buffer == NULL || o->out_buffer == NULL)
|
|
goto failed;
|
|
o->rpt = o->out_buffer;
|
|
return 1;
|
|
failed:
|
|
gzip_running_destroy(running, 0);
|
|
return -1;
|
|
}
|
|
#endif /* Libisofs_with_zliB */
|
|
|
|
|
|
/* ---------------------------- GzipFilterStreamData --------------------- */
|
|
|
|
|
|
/* Counts the number of active compression filters */
|
|
static off_t gzip_ref_count = 0;
|
|
|
|
/* Counts the number of active uncompression filters */
|
|
static off_t gunzip_ref_count = 0;
|
|
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
/* Parameter for deflateInit2() , see <zlib.h> */
|
|
|
|
/* ??? get this from zisofs.c ziso_compression_level ?
|
|
* ??? have an own global parameter API ?
|
|
* For now level 6 seems to be a fine compromise between speed and size.
|
|
*/
|
|
static int gzip_compression_level = 6;
|
|
|
|
#endif /* Libisofs_with_zliB */
|
|
|
|
|
|
/*
|
|
* The data payload of an individual Gzip Filter IsoStream
|
|
*/
|
|
/* IMPORTANT: Any change must be reflected by gzip_clone_stream() */
|
|
typedef struct
|
|
{
|
|
IsoStream *orig;
|
|
|
|
off_t size; /* -1 means that the size is unknown yet */
|
|
|
|
GzipFilterRuntime *running; /* is non-NULL when open */
|
|
|
|
ino_t id;
|
|
|
|
} GzipFilterStreamData;
|
|
|
|
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
/* Each individual GzipFilterStreamData needs a unique id number. */
|
|
/* >>> This is very suboptimal:
|
|
The counter can rollover.
|
|
*/
|
|
static ino_t gzip_ino_id = 0;
|
|
|
|
#endif /* Libisofs_with_zliB */
|
|
|
|
|
|
static
|
|
int gzip_stream_uncompress(IsoStream *stream, void *buf, size_t desired);
|
|
|
|
|
|
/*
|
|
* Methods for the IsoStreamIface of a Gzip Filter object.
|
|
*/
|
|
|
|
/*
|
|
* @param flag bit0= original stream is not open
|
|
*/
|
|
static
|
|
int gzip_stream_close_flag(IsoStream *stream, int flag)
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
GzipFilterStreamData *data;
|
|
|
|
if (stream == NULL) {
|
|
return ISO_NULL_POINTER;
|
|
}
|
|
data = stream->data;
|
|
|
|
if (data->running == NULL) {
|
|
return 1;
|
|
}
|
|
if (stream->class->read == &gzip_stream_uncompress) {
|
|
inflateEnd(&(data->running->strm));
|
|
} else {
|
|
deflateEnd(&(data->running->strm));
|
|
}
|
|
gzip_running_destroy(&(data->running), 0);
|
|
|
|
if (flag & 1)
|
|
return 1;
|
|
return iso_stream_close(data->orig);
|
|
|
|
#else
|
|
|
|
return ISO_ZLIB_NOT_ENABLED;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_stream_close(IsoStream *stream)
|
|
{
|
|
return gzip_stream_close_flag(stream, 0);
|
|
}
|
|
|
|
|
|
/*
|
|
* @param flag bit0= do not run .get_size() if size is < 0
|
|
*/
|
|
static
|
|
int gzip_stream_open_flag(IsoStream *stream, int flag)
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
GzipFilterStreamData *data;
|
|
GzipFilterRuntime *running = NULL;
|
|
int ret;
|
|
z_stream *strm;
|
|
|
|
if (stream == NULL) {
|
|
return ISO_NULL_POINTER;
|
|
}
|
|
data = (GzipFilterStreamData*) stream->data;
|
|
if (data->running != NULL) {
|
|
return ISO_FILE_ALREADY_OPENED;
|
|
}
|
|
if (data->size < 0 && !(flag & 1)) {
|
|
/* Do the size determination run now, so that the size gets cached
|
|
and .get_size() will not fail on an opened stream.
|
|
*/
|
|
stream->class->get_size(stream);
|
|
}
|
|
|
|
ret = gzip_running_new(&running,
|
|
stream->class->read == &gzip_stream_uncompress);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
data->running = running;
|
|
|
|
/* Start up zlib compression context */
|
|
strm = &(running->strm);
|
|
strm->zalloc = Z_NULL;
|
|
strm->zfree = Z_NULL;
|
|
strm->opaque = Z_NULL;
|
|
if (stream->class->read == &gzip_stream_uncompress) {
|
|
ret = inflateInit2(strm, 15 | 16);
|
|
} else {
|
|
ret = deflateInit2(strm, gzip_compression_level, Z_DEFLATED,
|
|
15 | 16, 8, Z_DEFAULT_STRATEGY);
|
|
}
|
|
if (ret != Z_OK)
|
|
return ISO_ZLIB_COMPR_ERR;
|
|
strm->next_out = (Bytef *) running->out_buffer;
|
|
strm->avail_out = running->out_buffer_size;
|
|
|
|
/* Open input stream */
|
|
ret = iso_stream_open(data->orig);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
return 1;
|
|
|
|
#else
|
|
|
|
return ISO_ZLIB_NOT_ENABLED;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_stream_open(IsoStream *stream)
|
|
{
|
|
return gzip_stream_open_flag(stream, 0);
|
|
}
|
|
|
|
|
|
/*
|
|
* @param flag bit1= uncompress rather than compress
|
|
*/
|
|
static
|
|
int gzip_stream_convert(IsoStream *stream, void *buf, size_t desired, int flag)
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
int ret, todo, cnv_ret, c_bytes;
|
|
GzipFilterStreamData *data;
|
|
GzipFilterRuntime *rng;
|
|
size_t fill = 0;
|
|
z_stream *strm;
|
|
|
|
if (stream == NULL) {
|
|
return ISO_NULL_POINTER;
|
|
}
|
|
data = stream->data;
|
|
rng= data->running;
|
|
if (rng == NULL) {
|
|
return ISO_FILE_NOT_OPENED;
|
|
}
|
|
strm = &(rng->strm);
|
|
if (rng->error_ret < 0) {
|
|
return rng->error_ret;
|
|
} else if (rng->error_ret == 0) {
|
|
if (rng->out_buffer_size - strm->avail_out
|
|
- (rng->rpt - rng->out_buffer) <= 0)
|
|
return 0;
|
|
}
|
|
|
|
while (1) {
|
|
|
|
/* Transfer eventual converted bytes from strm to buf */
|
|
c_bytes = rng->out_buffer_size - strm->avail_out
|
|
- (rng->rpt - rng->out_buffer);
|
|
if (c_bytes > 0) {
|
|
todo = desired - fill;
|
|
if (todo > c_bytes)
|
|
todo = c_bytes;
|
|
memcpy(((char *) buf) + fill, rng->rpt, todo);
|
|
rng->rpt += todo;
|
|
fill += todo;
|
|
rng->out_counter += todo;
|
|
}
|
|
|
|
if (fill >= desired || rng->error_ret == 0)
|
|
return fill;
|
|
|
|
/* All buffered out data are consumed now */
|
|
rng->rpt = rng->out_buffer;
|
|
strm->next_out = (Bytef *) rng->out_buffer;
|
|
strm->avail_out = rng->out_buffer_size;
|
|
|
|
if (strm->avail_in == 0) {
|
|
/* All pending input is consumed. Get new input. */
|
|
ret = iso_stream_read(data->orig, rng->in_buffer,
|
|
rng->in_buffer_size);
|
|
if (ret < 0)
|
|
return (rng->error_ret = ret);
|
|
if (ret == 0) {
|
|
if (flag & 2) {
|
|
/* Early input EOF */
|
|
return (rng->error_ret = ISO_ZLIB_EARLY_EOF);
|
|
} else {
|
|
/* Tell zlib by the next call that it is over */
|
|
rng->do_flush = Z_FINISH;
|
|
}
|
|
}
|
|
strm->next_in = (Bytef *) rng->in_buffer;
|
|
strm->avail_in = ret;
|
|
rng->in_counter += ret;
|
|
}
|
|
|
|
/* Submit input and fetch output until input is consumed */
|
|
while (1) {
|
|
if (flag & 2) {
|
|
cnv_ret = inflate(strm, rng->do_flush);
|
|
} else {
|
|
cnv_ret = deflate(strm, rng->do_flush);
|
|
}
|
|
if (cnv_ret == Z_STREAM_ERROR || cnv_ret == Z_BUF_ERROR) {
|
|
return (rng->error_ret = ISO_ZLIB_COMPR_ERR);
|
|
}
|
|
if ((int) strm->avail_out < rng->out_buffer_size)
|
|
break; /* output is available */
|
|
if (strm->avail_in == 0) /* all pending input consumed */
|
|
break;
|
|
}
|
|
if (cnv_ret == Z_STREAM_END)
|
|
rng->error_ret = 0;
|
|
}
|
|
return fill;
|
|
|
|
#else
|
|
|
|
return ISO_ZLIB_NOT_ENABLED;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
static
|
|
int gzip_stream_compress(IsoStream *stream, void *buf, size_t desired)
|
|
{
|
|
return gzip_stream_convert(stream, buf, desired, 0);
|
|
}
|
|
|
|
static
|
|
int gzip_stream_uncompress(IsoStream *stream, void *buf, size_t desired)
|
|
{
|
|
return gzip_stream_convert(stream, buf, desired, 2);
|
|
}
|
|
|
|
|
|
static
|
|
off_t gzip_stream_get_size(IsoStream *stream)
|
|
{
|
|
int ret, ret_close;
|
|
off_t count = 0;
|
|
GzipFilterStreamData *data;
|
|
char buf[64 * 1024];
|
|
size_t bufsize = 64 * 1024;
|
|
|
|
if (stream == NULL) {
|
|
return ISO_NULL_POINTER;
|
|
}
|
|
data = stream->data;
|
|
|
|
if (data->size >= 0) {
|
|
return data->size;
|
|
}
|
|
|
|
/* Run filter command and count output bytes */
|
|
ret = gzip_stream_open_flag(stream, 1);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
while (1) {
|
|
ret = stream->class->read(stream, buf, bufsize);
|
|
if (ret <= 0)
|
|
break;
|
|
count += ret;
|
|
}
|
|
ret_close = gzip_stream_close(stream);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (ret_close < 0)
|
|
return ret_close;
|
|
|
|
data->size = count;
|
|
return count;
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_stream_is_repeatable(IsoStream *stream)
|
|
{
|
|
/* Only repeatable streams are accepted as orig */
|
|
return 1;
|
|
}
|
|
|
|
|
|
static
|
|
void gzip_stream_get_id(IsoStream *stream, unsigned int *fs_id,
|
|
dev_t *dev_id, ino_t *ino_id)
|
|
{
|
|
GzipFilterStreamData *data;
|
|
|
|
data = stream->data;
|
|
*fs_id = ISO_FILTER_FS_ID;
|
|
*dev_id = ISO_FILTER_GZIP_DEV_ID;
|
|
*ino_id = data->id;
|
|
}
|
|
|
|
|
|
static
|
|
void gzip_stream_free(IsoStream *stream)
|
|
{
|
|
GzipFilterStreamData *data;
|
|
|
|
if (stream == NULL) {
|
|
return;
|
|
}
|
|
data = stream->data;
|
|
if (data->running != NULL) {
|
|
gzip_stream_close(stream);
|
|
}
|
|
if (stream->class->read == &gzip_stream_uncompress) {
|
|
if (--gunzip_ref_count < 0)
|
|
gunzip_ref_count = 0;
|
|
} else {
|
|
if (--gzip_ref_count < 0)
|
|
gzip_ref_count = 0;
|
|
}
|
|
iso_stream_unref(data->orig);
|
|
free(data);
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_update_size(IsoStream *stream)
|
|
{
|
|
/* By principle size is determined only once */
|
|
return 1;
|
|
}
|
|
|
|
|
|
static
|
|
IsoStream *gzip_get_input_stream(IsoStream *stream, int flag)
|
|
{
|
|
GzipFilterStreamData *data;
|
|
|
|
if (stream == NULL) {
|
|
return NULL;
|
|
}
|
|
data = stream->data;
|
|
return data->orig;
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_clone_stream(IsoStream *old_stream, IsoStream **new_stream, int flag)
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
int ret;
|
|
IsoStream *new_input_stream, *stream;
|
|
GzipFilterStreamData *stream_data, *old_stream_data;
|
|
|
|
if (flag)
|
|
return ISO_STREAM_NO_CLONE; /* unknown option required */
|
|
|
|
stream_data = calloc(1, sizeof(GzipFilterStreamData));
|
|
if (stream_data == NULL)
|
|
return ISO_OUT_OF_MEM;
|
|
ret = iso_stream_clone_filter_common(old_stream, &stream,
|
|
&new_input_stream, 0);
|
|
if (ret < 0) {
|
|
free((char *) stream_data);
|
|
return ret;
|
|
}
|
|
old_stream_data = (GzipFilterStreamData *) old_stream->data;
|
|
stream_data->orig = new_input_stream;
|
|
stream_data->size = old_stream_data->size;
|
|
stream_data->running = NULL;
|
|
stream_data->id = ++gzip_ino_id;
|
|
stream->data = stream_data;
|
|
*new_stream = stream;
|
|
return ISO_SUCCESS;
|
|
|
|
#else /* Libisofs_with_zliB */
|
|
|
|
return ISO_STREAM_NO_CLONE;
|
|
|
|
#endif /* ! Libisofs_with_zliB */
|
|
|
|
}
|
|
|
|
static
|
|
int gzip_cmp_ino(IsoStream *s1, IsoStream *s2);
|
|
|
|
static
|
|
int gzip_uncompress_cmp_ino(IsoStream *s1, IsoStream *s2);
|
|
|
|
|
|
IsoStreamIface gzip_stream_compress_class = {
|
|
4,
|
|
"gzip",
|
|
gzip_stream_open,
|
|
gzip_stream_close,
|
|
gzip_stream_get_size,
|
|
gzip_stream_compress,
|
|
gzip_stream_is_repeatable,
|
|
gzip_stream_get_id,
|
|
gzip_stream_free,
|
|
gzip_update_size,
|
|
gzip_get_input_stream,
|
|
gzip_cmp_ino,
|
|
gzip_clone_stream
|
|
};
|
|
|
|
|
|
IsoStreamIface gzip_stream_uncompress_class = {
|
|
4,
|
|
"pizg",
|
|
gzip_stream_open,
|
|
gzip_stream_close,
|
|
gzip_stream_get_size,
|
|
gzip_stream_uncompress,
|
|
gzip_stream_is_repeatable,
|
|
gzip_stream_get_id,
|
|
gzip_stream_free,
|
|
gzip_update_size,
|
|
gzip_get_input_stream,
|
|
gzip_uncompress_cmp_ino,
|
|
gzip_clone_stream
|
|
};
|
|
|
|
|
|
static
|
|
int gzip_cmp_ino(IsoStream *s1, IsoStream *s2)
|
|
{
|
|
/* This function may rely on being called by iso_stream_cmp_ino()
|
|
only with s1, s2 which both point to it as their .cmp_ino() function.
|
|
It would be a programming error to let any other than
|
|
gzip_stream_compress_class point to gzip_cmp_ino().
|
|
This fallback endangers transitivity of iso_stream_cmp_ino().
|
|
*/
|
|
if (s1->class != s2->class || (s1->class != &gzip_stream_compress_class &&
|
|
s2->class != &gzip_stream_compress_class))
|
|
return iso_stream_cmp_ino(s1, s2, 1);
|
|
|
|
/* Both streams apply the same treatment to their input streams */
|
|
return iso_stream_cmp_ino(iso_stream_get_input_stream(s1, 0),
|
|
iso_stream_get_input_stream(s2, 0), 0);
|
|
}
|
|
|
|
|
|
static
|
|
int gzip_uncompress_cmp_ino(IsoStream *s1, IsoStream *s2)
|
|
{
|
|
/* This function may rely on being called by iso_stream_cmp_ino()
|
|
only with s1, s2 which both point to it as their .cmp_ino() function.
|
|
It would be a programming error to let any other than
|
|
gzip_stream_uncompress_class point to gzip_uncompress_cmp_ino().
|
|
*/
|
|
if (s1->class != s2->class ||
|
|
(s1->class != &gzip_stream_uncompress_class &&
|
|
s2->class != &gzip_stream_uncompress_class))
|
|
return iso_stream_cmp_ino(s1, s2, 1);
|
|
|
|
/* Both streams apply the same treatment to their input streams */
|
|
return iso_stream_cmp_ino(iso_stream_get_input_stream(s1, 0),
|
|
iso_stream_get_input_stream(s2, 0), 0);
|
|
}
|
|
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
static
|
|
void gzip_filter_free(FilterContext *filter)
|
|
{
|
|
/* no data are allocated */;
|
|
}
|
|
|
|
/*
|
|
* @param flag bit1= Install a decompression filter
|
|
*/
|
|
static
|
|
int gzip_filter_get_filter(FilterContext *filter, IsoStream *original,
|
|
IsoStream **filtered, int flag)
|
|
{
|
|
IsoStream *str;
|
|
GzipFilterStreamData *data;
|
|
|
|
if (filter == NULL || original == NULL || filtered == NULL) {
|
|
return ISO_NULL_POINTER;
|
|
}
|
|
|
|
str = calloc(sizeof(IsoStream), 1);
|
|
if (str == NULL) {
|
|
return ISO_OUT_OF_MEM;
|
|
}
|
|
data = calloc(sizeof(GzipFilterStreamData), 1);
|
|
if (data == NULL) {
|
|
free(str);
|
|
return ISO_OUT_OF_MEM;
|
|
}
|
|
|
|
/* These data items are not owned by this filter object */
|
|
data->id = ++gzip_ino_id;
|
|
data->orig = original;
|
|
data->size = -1;
|
|
data->running = NULL;
|
|
|
|
/* get reference to the source */
|
|
iso_stream_ref(data->orig);
|
|
|
|
str->refcount = 1;
|
|
str->data = data;
|
|
if (flag & 2) {
|
|
str->class = &gzip_stream_uncompress_class;
|
|
gunzip_ref_count++;
|
|
} else {
|
|
str->class = &gzip_stream_compress_class;
|
|
gzip_ref_count++;
|
|
}
|
|
|
|
*filtered = str;
|
|
|
|
return ISO_SUCCESS;
|
|
}
|
|
|
|
/* To be called by iso_file_add_filter().
|
|
* The FilterContext input parameter is not furtherly needed for the
|
|
* emerging IsoStream.
|
|
*/
|
|
static
|
|
int gzip_filter_get_compressor(FilterContext *filter, IsoStream *original,
|
|
IsoStream **filtered)
|
|
{
|
|
return gzip_filter_get_filter(filter, original, filtered, 0);
|
|
}
|
|
|
|
static
|
|
int gzip_filter_get_uncompressor(FilterContext *filter, IsoStream *original,
|
|
IsoStream **filtered)
|
|
{
|
|
return gzip_filter_get_filter(filter, original, filtered, 2);
|
|
}
|
|
|
|
|
|
/* Produce a parameter object suitable for iso_file_add_filter().
|
|
* It may be disposed by free() after all those calls are made.
|
|
*
|
|
* This is quite a dummy as it does not carry individual data.
|
|
* @param flag bit1= Install a decompression filter
|
|
*/
|
|
static
|
|
int gzip_create_context(FilterContext **filter, int flag)
|
|
{
|
|
FilterContext *f;
|
|
|
|
*filter = f = calloc(1, sizeof(FilterContext));
|
|
if (f == NULL) {
|
|
return ISO_OUT_OF_MEM;
|
|
}
|
|
f->refcount = 1;
|
|
f->version = 0;
|
|
f->data = NULL;
|
|
f->free = gzip_filter_free;
|
|
if (flag & 2)
|
|
f->get_filter = gzip_filter_get_uncompressor;
|
|
else
|
|
f->get_filter = gzip_filter_get_compressor;
|
|
return ISO_SUCCESS;
|
|
}
|
|
|
|
#endif /* Libisofs_with_zliB */
|
|
|
|
/*
|
|
* @param flag bit0= if_block_reduction rather than if_reduction
|
|
* bit1= Install a decompression filter
|
|
* bit2= only inquire availability of gzip filtering
|
|
* bit3= do not inquire size
|
|
*/
|
|
int gzip_add_filter(IsoFile *file, int flag)
|
|
{
|
|
|
|
#ifdef Libisofs_with_zliB
|
|
|
|
int ret;
|
|
FilterContext *f = NULL;
|
|
IsoStream *stream;
|
|
off_t original_size = 0, filtered_size = 0;
|
|
|
|
if (flag & 4)
|
|
return 2;
|
|
|
|
original_size = iso_file_get_size(file);
|
|
|
|
ret = gzip_create_context(&f, flag & 2);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
ret = iso_file_add_filter(file, f, 0);
|
|
free(f);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
if (flag & 8) /* size will be filled in by caller */
|
|
return ISO_SUCCESS;
|
|
|
|
/* Run a full filter process getsize so that the size is cached */
|
|
stream = iso_file_get_stream(file);
|
|
filtered_size = iso_stream_get_size(stream);
|
|
if (filtered_size < 0) {
|
|
iso_file_remove_filter(file, 0);
|
|
return filtered_size;
|
|
}
|
|
if ((filtered_size >= original_size ||
|
|
((flag & 1) && filtered_size / 2048 >= original_size / 2048))
|
|
&& !(flag & 2)){
|
|
ret = iso_file_remove_filter(file, 0);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
return 2;
|
|
}
|
|
return ISO_SUCCESS;
|
|
|
|
#else
|
|
|
|
return ISO_ZLIB_NOT_ENABLED;
|
|
|
|
#endif /* ! Libisofs_with_zliB */
|
|
|
|
}
|
|
|
|
|
|
/* API function */
|
|
int iso_file_add_gzip_filter(IsoFile *file, int flag)
|
|
{
|
|
return gzip_add_filter(file, flag & ~8);
|
|
}
|
|
|
|
|
|
/* API function */
|
|
int iso_gzip_get_refcounts(off_t *gzip_count, off_t *gunzip_count, int flag)
|
|
{
|
|
*gzip_count = gzip_ref_count;
|
|
*gunzip_count = gunzip_ref_count;
|
|
return ISO_SUCCESS;
|
|
}
|
|
|