#include <config.h>
-
+#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <libpspp/assertion.h>
#include <libpspp/compiler.h>
-#include <byteswap.h>
-#include <crc.h>
-
-#include "inflate.h"
-
#include "str.h"
+#include "integer-format.h"
#include "zip-reader.h"
#include "zip-private.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)
-{
- return fread (buf, 1, n, zm->fp);
-}
-
-static bool
-stored_init (struct zip_member *zm UNUSED)
+struct zip_member
{
- return true;
-}
+ char *file_name; /* File name. */
+ char *member_name; /* Member name. */
+ 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. */
+ const struct decompressor *decompressor;
+
+ size_t bytes_unread; /* Number of bytes left in the member available for reading */
+ 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 (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;
}
-
struct zip_reader
{
- char *filename; /* The name of the file from which the data is read */
- FILE *fr; /* The stream from which the meta data is read */
- uint16_t n_members; /* The number of members in this archive */
- struct zip_member **members; /* The members (may be null pointers until the headers have been read */
- int nm;
- struct string *errs;
+ char *file_name; /* The name of the file from which the data is read */
+ uint16_t n_entries; /* Number of directory entries. */
+ struct zip_entry *entries; /* Directory entries. */
+ struct string *errs; /* A string to hold error messages. This
+ string is NOT owned by this object. */
+};
+
+struct zip_entry
+{
+ 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. */
+ char *name; /* Name of member file. */
};
void
zip_member_finish (struct zip_member *zm)
{
- ds_clear (zm->errmsgs);
- /* Probably not useful, because we would have to read right to the end of the member
- if (zm->expected_crc != zm->crc)
+ if (zm)
{
- ds_put_cstr (zm->errs, _("CRC error reading zip"));
+ free (zm->file_name);
+ free (zm->member_name);
+ ds_clear (zm->errmsgs);
+ zm->decompressor->finish (zm);
+ fclose (zm->fp);
+ free (zm);
}
- */
- zip_member_unref (zm);
}
-
-
/* Destroy the zip reader */
void
zip_reader_destroy (struct zip_reader *zr)
if (zr == NULL)
return;
- fclose (zr->fr);
- free (zr->filename);
+ free (zr->file_name);
- for (i = 0; i < zr->n_members; ++i)
+ for (i = 0; i < zr->n_entries; ++i)
{
- zip_member_unref (zr->members[i]);
+ struct zip_entry *ze = &zr->entries[i];
+ free (ze->name);
}
- free (zr->members);
+ free (zr->entries);
free (zr);
}
-void
-zm_dump (const struct zip_member *zm)
-{
- printf ("%d\t%08x\t %s\n", zm->ucomp_size, zm->expected_crc, zm->name);
-}
-
-
/* Skip N bytes in F */
static void
skip_bytes (FILE *f, size_t n)
return (n == fread (x, 1, n, f));
}
-static bool get_u32 (FILE *f, uint32_t *v) WARN_UNUSED_RESULT;
-
-
/* Read a 32 bit value from F */
-static bool
+static bool WARN_UNUSED_RESULT
get_u32 (FILE *f, uint32_t *v)
{
uint32_t x;
if (!get_bytes (f, &x, sizeof x))
return false;
-#ifdef WORDS_BIGENDIAN
- *v = bswap_32 (x);
-#else
- *v = x;
-#endif
+ *v = le_to_native32 (x);
return true;
}
-static bool get_u16 (FILE *f, uint16_t *v) WARN_UNUSED_RESULT;
-
-
/* Read a 16 bit value from F */
-static bool
+static bool WARN_UNUSED_RESULT
get_u16 (FILE *f, uint16_t *v)
{
uint16_t x;
if (!get_bytes (f, &x, sizeof x))
return false;
-#ifdef WORDS_BIGENDIAN
- *v = bswap_16 (x);
-#else
- *v = x;
-#endif
+ *v = le_to_native16 (x);
return true;
}
/* Read 32 bit integer and compare it with EXPECTED.
place an error string in ERR if necessary. */
static bool
-check_magic (FILE *f, uint32_t expected, struct string *err)
+check_magic (FILE *f, const char *file_name,
+ uint32_t expected, struct string *err)
{
uint32_t magic;
if ((expected != magic))
{
ds_put_format (err,
- _("Corrupt file at 0x%llx: Expected %"PRIx32"; got %"PRIx32),
- (long long int) ftello (f) - sizeof (uint32_t), expected, magic);
+ _("%s: corrupt archive at 0x%llx: "
+ "expected %#"PRIx32" but got %#"PRIx32),
+ file_name,
+ (long long int) ftello (f) - sizeof (uint32_t),
+ expected, magic);
return false;
}
ds_clear (zm->errmsgs);
- if ( bytes > zm->bytes_unread)
+ if (bytes > zm->bytes_unread)
bytes = zm->bytes_unread;
- bytes_read = decompressors[zm->compression].read (zm, buf, bytes);
- if ( bytes_read < 0)
+ bytes_read = zm->decompressor->read (zm, buf, bytes);
+ if (bytes_read < 0)
return bytes_read;
- zm->crc = crc32_update (zm->crc, buf, bytes_read);
-
zm->bytes_unread -= bytes_read;
return bytes_read;
}
-
-/*
- Read a local file header from ZR and add it to ZR's internal array.
- Returns a pointer to the member read. This pointer belongs to ZR.
- If the caller wishes to control it, she should ref it with
- zip_member_ref.
-*/
-static struct zip_member *
-zip_header_read_next (struct zip_reader *zr)
+/* Read all of ZM into memory, storing the data in *DATAP and its size in *NP.
+ Returns NULL if successful, otherwise an error string that the caller
+ must eventually free(). */
+char * WARN_UNUSED_RESULT
+zip_member_read_all (struct zip_reader *zr, const char *member_name,
+ void **datap, size_t *np)
{
- struct zip_member *zm = xzalloc (sizeof *zm);
+ struct zip_member *zm = zip_member_open (zr, member_name);
+ if (!zm)
+ {
+ *datap = NULL;
+ *np = 0;
+ return ds_steal_cstr (zr->errs);
+ }
+
+ *datap = xmalloc (zm->ucomp_size);
+ *np = zm->ucomp_size;
+ uint8_t *data = *datap;
+ while (zm->bytes_unread)
+ if (zip_member_read (zm, data + (zm->ucomp_size - zm->bytes_unread),
+ zm->bytes_unread) == -1)
+ {
+ zip_member_finish (zm);
+ free (*datap);
+ *datap = NULL;
+ *np = 0;
+ return ds_steal_cstr (zr->errs);
+ }
+
+ zip_member_finish (zm);
+ return NULL;
+}
+
+/* Read a central directory header from FILE and initializes ZE with it.
+ Returns true if successful, false otherwise. On error, appends error
+ messages to ERRS. */
+static bool
+zip_header_read_next (FILE *file, const char *file_name,
+ struct zip_entry *ze, struct string *errs)
+{
uint16_t v, nlen, extralen;
uint16_t gp, time, date;
+ uint32_t expected_crc;
uint16_t clen, diskstart, iattr;
uint32_t eattr;
uint16_t comp_type;
- ds_clear (zr->errs);
- zm->errmsgs = zr->errs;
-
- if ( ! check_magic (zr->fr, MAGIC_SOCD, zr->errs))
- return NULL;
-
- if (! get_u16 (zr->fr, &v)) return NULL;
-
- if (! get_u16 (zr->fr, &v)) return NULL;
- if (! get_u16 (zr->fr, &gp)) return NULL;
- if (! get_u16 (zr->fr, &comp_type)) return NULL;
-
- zm->compression = comp_code (zm, comp_type);
-
- if (! get_u16 (zr->fr, &time)) return NULL;
- if (! get_u16 (zr->fr, &date)) return NULL;
- if (! get_u32 (zr->fr, &zm->expected_crc)) return NULL;
- if (! get_u32 (zr->fr, &zm->comp_size)) return NULL;
- if (! get_u32 (zr->fr, &zm->ucomp_size)) return NULL;
- if (! get_u16 (zr->fr, &nlen)) return NULL;
- if (! get_u16 (zr->fr, &extralen)) return NULL;
- if (! get_u16 (zr->fr, &clen)) return NULL;
- if (! get_u16 (zr->fr, &diskstart)) return NULL;
- if (! get_u16 (zr->fr, &iattr)) return NULL;
- if (! get_u32 (zr->fr, &eattr)) return NULL;
- if (! get_u32 (zr->fr, &zm->offset)) return NULL;
-
- zm->name = xzalloc (nlen + 1);
- if (! get_bytes (zr->fr, zm->name, nlen)) return NULL;
-
- skip_bytes (zr->fr, extralen);
-
- zr->members[zr->nm++] = zm;
-
- zm->fp = fopen (zr->filename, "rb");
- zm->ref_cnt = 1;
+ if (! check_magic (file, file_name, MAGIC_SOCD, errs))
+ return false;
+ if (! get_u16 (file, &v)) return false;
+ if (! get_u16 (file, &v)) return false;
+ if (! get_u16 (file, &gp)) return false;
+ if (! get_u16 (file, &comp_type)) return false;
+ if (! get_u16 (file, &time)) return false;
+ if (! get_u16 (file, &date)) return false;
+ if (! get_u32 (file, &expected_crc)) return false;
+ if (! get_u32 (file, &ze->comp_size)) return false;
+ if (! get_u32 (file, &ze->ucomp_size)) return false;
+ if (! get_u16 (file, &nlen)) return false;
+ if (! get_u16 (file, &extralen)) return false;
+ if (! get_u16 (file, &clen)) return false;
+ if (! get_u16 (file, &diskstart)) return false;
+ if (! get_u16 (file, &iattr)) return false;
+ if (! get_u32 (file, &eattr)) return false;
+ if (! get_u32 (file, &ze->offset)) return false;
+
+ ze->name = xzalloc (nlen + 1);
+ if (! get_bytes (file, ze->name, nlen)) return false;
+
+ skip_bytes (file, extralen);
- return zm;
+ return true;
}
-/* Create a reader from the zip called FILENAME */
+/* Create a reader from the zip called FILE_NAME */
struct zip_reader *
-zip_reader_create (const char *filename, struct string *errs)
+zip_reader_create (const char *file_name, struct string *errs)
{
- uint16_t disknum, total_members;
+ uint16_t disknum, n_members, total_members;
off_t offset = 0;
uint32_t central_dir_start, central_dir_length;
struct zip_reader *zr = xzalloc (sizeof *zr);
zr->errs = errs;
- if ( zr->errs)
+ if (zr->errs)
ds_init_empty (zr->errs);
- zr->nm = 0;
-
- zr->fr = fopen (filename, "rb");
- if (NULL == zr->fr)
+ FILE *file = fopen (file_name, "rb");
+ if (!file)
{
- ds_put_cstr (zr->errs, strerror (errno));
+ ds_put_format (zr->errs, _("%s: open failed (%s)"),
+ file_name, strerror (errno));
free (zr);
return NULL;
}
- if ( ! check_magic (zr->fr, MAGIC_LHDR, zr->errs))
+ if (! check_magic (file, file_name, MAGIC_LHDR, zr->errs))
{
- fclose (zr->fr);
+ fclose (file);
free (zr);
return NULL;
}
- if ( ! find_eocd (zr->fr, &offset))
+ if (! find_eocd (file, &offset))
{
- ds_put_format (zr->errs, _("Cannot find central directory"));
- fclose (zr->fr);
+ ds_put_format (zr->errs, _("%s: cannot find central directory"),
+ file_name);
+ fclose (file);
free (zr);
return NULL;
}
- if ( 0 != fseeko (zr->fr, offset, SEEK_SET))
+ if (0 != fseeko (file, offset, SEEK_SET))
{
- const char *mm = strerror (errno);
- ds_put_format (zr->errs, _("Failed to seek to end of central directory record: %s"), mm);
- fclose (zr->fr);
+ ds_put_format (zr->errs, _("%s: seek failed (%s)"),
+ file_name, strerror (errno));
+ fclose (file);
free (zr);
return NULL;
}
- if ( ! check_magic (zr->fr, MAGIC_EOCD, zr->errs))
+ if (! check_magic (file, file_name, MAGIC_EOCD, zr->errs))
{
- fclose (zr->fr);
+ fclose (file);
free (zr);
return NULL;
}
- if (! get_u16 (zr->fr, &disknum)) return NULL;
- if (! get_u16 (zr->fr, &disknum)) return NULL;
+ if (! get_u16 (file, &disknum)
+ || ! get_u16 (file, &disknum)
- if (! get_u16 (zr->fr, &zr->n_members)) return NULL;
- if (! get_u16 (zr->fr, &total_members)) return NULL;
+ || ! get_u16 (file, &n_members)
+ || ! get_u16 (file, &total_members)
- if (! get_u32 (zr->fr, ¢ral_dir_length)) return NULL;
- if (! get_u32 (zr->fr, ¢ral_dir_start)) return NULL;
+ || ! get_u32 (file, ¢ral_dir_length)
+ || ! get_u32 (file, ¢ral_dir_start))
+ {
+ fclose (file);
+ free (zr);
+ return NULL;
+ }
- if ( 0 != fseeko (zr->fr, central_dir_start, SEEK_SET))
+ if (0 != fseeko (file, central_dir_start, SEEK_SET))
{
- const char *mm = strerror (errno);
- ds_put_format (zr->errs, _("Failed to seek to central directory: %s"), mm);
- fclose (zr->fr);
+ ds_put_format (zr->errs, _("%s: seek failed (%s)"),
+ file_name, strerror (errno));
+ fclose (file);
free (zr);
return NULL;
}
- zr->members = xcalloc (zr->n_members, sizeof (*zr->members));
- memset (zr->members, 0, zr->n_members * sizeof (*zr->members));
+ zr->file_name = xstrdup (file_name);
- zr->filename = strdup (filename);
+ zr->entries = xcalloc (n_members, sizeof *zr->entries);
+ for (int i = 0; i < n_members; i++)
+ {
+ if (!zip_header_read_next (file, file_name,
+ &zr->entries[zr->n_entries], errs))
+ {
+ fclose (file);
+ zip_reader_destroy (zr);
+ return NULL;
+ }
+ zr->n_entries++;
+ }
return zr;
}
+static struct zip_entry *
+zip_entry_find (const struct zip_reader *zr, const char *member)
+{
+ for (int i = 0; i < zr->n_entries; ++i)
+ {
+ struct zip_entry *ze = &zr->entries[i];
+ if (0 == strcmp (ze->name, member))
+ return ze;
+ }
+ return NULL;
+}
+const char *
+zip_reader_get_member_name(const struct zip_reader *zr, size_t idx)
+{
+ return idx < zr->n_entries ? zr->entries[idx].name : NULL;
+}
+
+/* Returns true if ZR contains a member named MEMBER, false otherwise. */
+bool
+zip_reader_contains_member (const struct zip_reader *zr, const char *member)
+{
+ return zip_entry_find (zr, member) != NULL;
+}
/* Return the member called MEMBER from the reader ZR */
struct zip_member *
zip_member_open (struct zip_reader *zr, const char *member)
{
- uint16_t v, nlen, extra_len;
- uint16_t gp, comp_type, time, date;
- uint32_t ucomp_size, comp_size;
-
- uint32_t crc;
- bool new_member = false;
- char *name = NULL;
-
- int i;
- struct zip_member *zm = NULL;
-
- if ( zr == NULL)
- return NULL;
-
- for (i = 0; i < zr->n_members; ++i)
- {
- zm = zr->members[i];
-
- if (zm == NULL)
- {
- zm = zr->members[i] = zip_header_read_next (zr);
- new_member = true;
- }
- if (zm && 0 == strcmp (zm->name, member))
- break;
- else
- zm = NULL;
- }
-
- if ( zm == NULL)
- return NULL;
-
- if ( 0 != fseeko (zm->fp, zm->offset, SEEK_SET))
+ struct zip_entry *ze = zip_entry_find (zr, member);
+ if (ze == NULL)
{
- const char *mm = strerror (errno);
- ds_put_format (zm->errmsgs, _("Failed to seek to start of member `%s': %s"), zm->name, mm);
+ ds_put_format (zr->errs, _("%s: unknown member \"%s\""),
+ zr->file_name, member);
return NULL;
}
- if ( ! check_magic (zm->fp, MAGIC_LHDR, zr->errs))
+ FILE *fp = fopen (zr->file_name, "rb");
+ if (!fp)
{
+ ds_put_format (zr->errs, _("%s: open failed (%s)"),
+ zr->file_name, strerror (errno));
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);
- if (! get_u16 (zm->fp, &time)) return NULL;
- if (! get_u16 (zm->fp, &date)) return NULL;
- if (! get_u32 (zm->fp, &crc)) return NULL;
- if (! get_u32 (zm->fp, &comp_size)) return NULL;
-
- if (! get_u32 (zm->fp, &ucomp_size)) return NULL;
- if (! get_u16 (zm->fp, &nlen)) return NULL;
- if (! get_u16 (zm->fp, &extra_len)) return NULL;
-
- name = xzalloc (nlen + 1);
+ struct zip_member *zm = xmalloc (sizeof *zm);
+ zm->file_name = xstrdup (zr->file_name);
+ zm->member_name = xstrdup (member);
+ zm->fp = fp;
+ zm->offset = ze->offset;
+ zm->comp_size = ze->comp_size;
+ zm->ucomp_size = ze->ucomp_size;
+ zm->decompressor = NULL;
+ zm->bytes_unread = ze->ucomp_size;
+ zm->errmsgs = zr->errs;
+ zm->aux = NULL;
- if (! get_bytes (zm->fp, name, nlen)) return NULL;
+ if (0 != fseeko (zm->fp, zm->offset, SEEK_SET))
+ {
+ ds_put_format (zr->errs, _("%s: seek failed (%s)"),
+ ze->name, strerror (errno));
+ goto error;
+ }
- skip_bytes (zm->fp, extra_len);
+ if (! check_magic (zm->fp, zr->file_name, MAGIC_LHDR, zr->errs))
+ goto error;
- if (strcmp (name, zm->name) != 0)
+ uint16_t v, nlen, extra_len;
+ uint16_t gp, comp_type, time, date;
+ uint32_t ucomp_size, comp_size;
+ uint32_t crc;
+ if (! get_u16 (zm->fp, &v)) goto error;
+ if (! get_u16 (zm->fp, &gp)) goto error;
+ if (! get_u16 (zm->fp, &comp_type)) goto error;
+ zm->decompressor = get_decompressor (comp_type);
+ if (! zm->decompressor) goto error;
+ if (! get_u16 (zm->fp, &time)) goto error;
+ if (! get_u16 (zm->fp, &date)) goto error;
+ if (! get_u32 (zm->fp, &crc)) goto error;
+ if (! get_u32 (zm->fp, &comp_size)) goto error;
+
+ if (! get_u32 (zm->fp, &ucomp_size)) goto error;
+ if (! get_u16 (zm->fp, &nlen)) goto error;
+ if (! get_u16 (zm->fp, &extra_len)) goto error;
+
+ char *name = xzalloc (nlen + 1);
+ if (! get_bytes (zm->fp, name, nlen))
+ {
+ free (name);
+ goto error;
+ }
+ if (strcmp (name, ze->name) != 0)
{
ds_put_format (zm->errmsgs,
- _("Name mismatch in zip archive. Central directory says `%s'; local file header says `%s'"),
- zm->name, name);
+ _("%s: name mismatch between central directory (%s) "
+ "and local file header (%s)"),
+ zm->file_name, ze->name, name);
free (name);
- free (zm);
- return NULL;
+ goto error;
}
-
free (name);
- zm->bytes_unread = zm->ucomp_size;
-
- if ( !new_member)
- decompressors[zm->compression].finish (zm);
+ skip_bytes (zm->fp, extra_len);
- if (!decompressors[zm->compression].init (zm) )
- return NULL;
+ if (!zm->decompressor->init (zm))
+ goto error;
return zm;
-}
-void
-zip_member_ref (struct zip_member *zm)
-{
- zm->ref_cnt++;
+error:
+ fclose (zm->fp);
+ free (zm->file_name);
+ free (zm->member_name);
+ free (zm);
+ return NULL;
}
-
-
-
-void
-zip_member_unref (struct zip_member *zm)
-{
- if ( zm == NULL)
- return;
-
- if (--zm->ref_cnt == 0)
- {
- decompressors[zm->compression].finish (zm);
- if (zm->fp)
- fclose (zm->fp);
- free (zm->name);
- free (zm);
- }
-}
-
-
\f
static bool probe_magic (FILE *fp, uint32_t magic, off_t start, off_t stop, off_t *off);
because that is the minimum length of the EndOfCentralDirectory
record.
*/
- if ( 0 > fseeko (fp, -22, SEEK_END))
+ if (0 > fseeko (fp, -22, SEEK_END))
{
return false;
}
{
found = probe_magic (fp, magic, start, stop, off);
/* FIXME: For extra confidence lookup the directory start record here*/
- if ( start == 0)
+ if (start == 0)
break;
stop = start + sizeof (magic);
start >>= 1;
}
- while (!found );
+ while (!found);
return found;
}
unsigned char seq[4];
unsigned char byte;
- if ( 0 > fseeko (fp, start, SEEK_SET))
+ if (0 > fseeko (fp, start, SEEK_SET))
{
return -1;
}
if (1 != fread (&byte, 1, 1, fp))
break;
- if ( byte == seq[state])
+ if (byte == seq[state])
state++;
else
state = 0;
- if ( state == 4)
+ if (state == 4)
{
*off = ftello (fp) - 4;
return true;
}
start++;
- if ( start >= stop)
+ if (start >= stop)
break;
}
while (!feof (fp));
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,
+ _("%s: cannot initialize inflator (%s)"),
+ zm->file_name, 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, _("%s: error inflating \"%s\" (%s)"),
+ zm->file_name, zm->member_name, zError (r));
+
+ return -1;
+}
+
+static const struct decompressor inflate_decompressor =
+ {inflate_init, inflate_read, inflate_finish};