#include <config.h>
-
+#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <byteswap.h>
#include <crc.h>
-#include "inflate.h"
-
#include "str.h"
#include "zip-reader.h"
#define _(msgid) gettext (msgid)
#define N_(msgid) (msgid)
-
-static bool find_eocd (FILE *fp, off_t *off);
-
-static int
-stored_read (struct zip_member *zm, void *buf, size_t n)
+struct zip_member
{
- return fread (buf, 1, n, zm->fp);
-}
+ FILE *fp; /* The stream from which the data is read */
+ uint32_t offset; /* Starting offset in file. */
+ uint32_t comp_size; /* Length of member file data, in bytes. */
+ uint32_t ucomp_size; /* Uncompressed length of member file data, in bytes. */
+ uint32_t expected_crc; /* CRC-32 of member file data.. */
+ char *name; /* Name of member file. */
+ uint32_t crc;
+ const struct decompressor *decompressor;
-static bool
-stored_init (struct zip_member *zm UNUSED)
-{
- return true;
-}
+ size_t bytes_unread; /* Number of bytes left in the member available for reading */
+ int ref_cnt;
+ struct string *errmsgs; /* A string to hold error messages.
+ This string is NOT owned by this object. */
+ void *aux;
+};
-static void
-stored_finish (struct zip_member *zm UNUSED)
+struct decompressor
{
- /* Nothing required */
-}
-
+ bool (*init) (struct zip_member *);
+ int (*read) (struct zip_member *, void *, size_t);
+ void (*finish) (struct zip_member *);
+};
+static const struct decompressor stored_decompressor;
+static const struct decompressor inflate_decompressor;
-static struct decompressor decompressors[n_COMPRESSION] =
- {
- {stored_init, stored_read, stored_finish},
- {inflate_init, inflate_read, inflate_finish}
- };
+static bool find_eocd (FILE *fp, off_t *off);
-static enum compression
-comp_code (struct zip_member *zm, uint16_t c)
+static const struct decompressor *
+get_decompressor (struct zip_member *zm, uint16_t c)
{
- enum compression which;
assert (zm->errmsgs);
switch (c)
{
case 0:
- which = COMPRESSION_STORED;
- break;
+ return &stored_decompressor;
+
case 8:
- which = COMPRESSION_INFLATE;
- break;
+ return &inflate_decompressor;
+
default:
ds_put_format (zm->errmsgs, _("Unsupported compression type (%d)"), c);
- which = n_COMPRESSION;
- break;
+ return NULL;
}
- return which;
}
if ( bytes > zm->bytes_unread)
bytes = zm->bytes_unread;
- bytes_read = decompressors[zm->compression].read (zm, buf, bytes);
+ bytes_read = zm->decompressor->read (zm, buf, bytes);
if ( bytes_read < 0)
return bytes_read;
if (! get_u16 (zr->fr, &gp)) return NULL;
if (! get_u16 (zr->fr, &comp_type)) return NULL;
- zm->compression = comp_code (zm, comp_type);
+ zm->decompressor = get_decompressor (zm, comp_type);
+ if (! zm->decompressor) return NULL;
if (! get_u16 (zr->fr, &time)) return NULL;
if (! get_u16 (zr->fr, &date)) return NULL;
if (! get_u16 (zm->fp, &v)) return NULL;
if (! get_u16 (zm->fp, &gp)) return NULL;
if (! get_u16 (zm->fp, &comp_type)) return NULL;
- zm->compression = comp_code (zm, comp_type);
+ zm->decompressor = get_decompressor (zm, comp_type);
+ if (! zm->decompressor) return NULL;
if (! get_u16 (zm->fp, &time)) return NULL;
if (! get_u16 (zm->fp, &date)) return NULL;
if (! get_u32 (zm->fp, &crc)) return NULL;
zm->bytes_unread = zm->ucomp_size;
if ( !new_member)
- decompressors[zm->compression].finish (zm);
+ zm->decompressor->finish (zm);
- if (!decompressors[zm->compression].init (zm) )
+ if (!zm->decompressor->init (zm) )
return NULL;
return zm;
if (--zm->ref_cnt == 0)
{
- decompressors[zm->compression].finish (zm);
+ zm->decompressor->finish (zm);
if (zm->fp)
fclose (zm->fp);
free (zm->name);
return false;
}
+\f
+/* Null decompressor. */
+
+static int
+stored_read (struct zip_member *zm, void *buf, size_t n)
+{
+ return fread (buf, 1, n, zm->fp);
+}
+
+static bool
+stored_init (struct zip_member *zm UNUSED)
+{
+ return true;
+}
+
+static void
+stored_finish (struct zip_member *zm UNUSED)
+{
+ /* Nothing required */
+}
+
+static const struct decompressor stored_decompressor =
+ {stored_init, stored_read, stored_finish};
+\f
+/* Inflate decompressor. */
+
+#undef crc32
+#include <zlib.h>
+
+#define UCOMPSIZE 4096
+
+struct inflator
+{
+ z_stream zss;
+ int state;
+ unsigned char ucomp[UCOMPSIZE];
+ size_t bytes_uncomp;
+ size_t ucomp_bytes_read;
+
+ /* Two bitfields as defined by RFC1950 */
+ uint16_t cmf_flg ;
+};
+
+static void
+inflate_finish (struct zip_member *zm)
+{
+ struct inflator *inf = zm->aux;
+
+ inflateEnd (&inf->zss);
+
+ free (inf);
+}
+
+static bool
+inflate_init (struct zip_member *zm)
+{
+ int r;
+ struct inflator *inf = xzalloc (sizeof *inf);
+
+ uint16_t flg = 0 ;
+ uint16_t cmf = 0x8; /* Always 8 for inflate */
+
+ const uint16_t cinfo = 7; /* log_2(Window size) - 8 */
+
+ cmf |= cinfo << 4; /* Put cinfo into the high nibble */
+
+ /* make these into a 16 bit word */
+ inf->cmf_flg = (cmf << 8 ) | flg;
+
+ /* Set the check bits */
+ inf->cmf_flg += 31 - (inf->cmf_flg % 31);
+ assert (inf->cmf_flg % 31 == 0);
+
+ inf->zss.next_in = Z_NULL;
+ inf->zss.avail_in = 0;
+ inf->zss.zalloc = Z_NULL;
+ inf->zss.zfree = Z_NULL;
+ inf->zss.opaque = Z_NULL;
+ r = inflateInit (&inf->zss);
+
+ if ( Z_OK != r)
+ {
+ ds_put_format (zm->errmsgs, _("Cannot initialize inflator: %s"), zError (r));
+ return false;
+ }
+
+ zm->aux = inf;
+
+ return true;
+}
+
+static int
+inflate_read (struct zip_member *zm, void *buf, size_t n)
+{
+ int r;
+ struct inflator *inf = zm->aux;
+
+ if (inf->zss.avail_in == 0)
+ {
+ int bytes_read;
+ int bytes_to_read;
+ int pad = 0;
+
+ if ( inf->state == 0)
+ {
+ inf->ucomp[1] = inf->cmf_flg ;
+ inf->ucomp[0] = inf->cmf_flg >> 8 ;
+
+ pad = 2;
+ inf->state++;
+ }
+
+ bytes_to_read = zm->comp_size - inf->ucomp_bytes_read;
+
+ if (bytes_to_read == 0)
+ return 0;
+
+ if (bytes_to_read > UCOMPSIZE)
+ bytes_to_read = UCOMPSIZE;
+
+ bytes_read = fread (inf->ucomp + pad, 1, bytes_to_read - pad, zm->fp);
+
+ inf->ucomp_bytes_read += bytes_read;
+
+ inf->zss.avail_in = bytes_read + pad;
+ inf->zss.next_in = inf->ucomp;
+ }
+ inf->zss.avail_out = n;
+ inf->zss.next_out = buf;
+
+ r = inflate (&inf->zss, Z_NO_FLUSH);
+ if ( Z_OK == r)
+ {
+ return n - inf->zss.avail_out;
+ }
+
+ ds_put_format (zm->errmsgs, _("Error inflating: %s"), zError (r));
+
+ return -1;
+}
+
+static const struct decompressor inflate_decompressor =
+ {inflate_init, inflate_read, inflate_finish};
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