/* PSPP - a program for statistical analysis.
- Copyright (C) 2011 Free Software Foundation, Inc.
+ Copyright (C) 2011, 2013, 2014, 2021 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <config.h>
+#include "libpspp/zip-reader.h"
+#include "libpspp/zip-private.h"
+#include <errno.h>
+#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <errno.h>
-#include <xalloc.h>
-#include <libpspp/assertion.h>
-
-#include <byteswap.h>
-#include <crc.h>
-
-#include "inflate.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
+#include "libpspp/compiler.h"
+#include "libpspp/integer-format.h"
+#include "libpspp/str.h"
-#include "str.h"
-
-#include "zip-reader.h"
-#include "zip-private.h"
+#include "gl/xalloc.h"
#include "gettext.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 */
+ char *error; /* Error message, if any. */
+ void *aux;
+};
-static void
-stored_finish (struct zip_member *zm UNUSED)
+struct decompressor
{
- /* Nothing required */
-}
-
+ char *(*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},
-#if HAVE_ZLIB_H
- {inflate_init, inflate_read, inflate_finish}
-#endif
- };
+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;
switch (c)
{
case 0:
- which = COMPRESSION_STORED;
- break;
-#if HAVE_ZLIB_H
+ return &stored_decompressor;
+
case 8:
- which = COMPRESSION_INFLATE;
- break;
-#endif
+ return &inflate_decompressor;
+
default:
- ds_put_format (zm->errs, _("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;
+ int ref_cnt;
+ 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 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. */
+};
+
+char * WARN_UNUSED_RESULT
+zip_member_steal_error (struct zip_member *zm)
+{
+ char *retval = zm->error;
+ zm->error = NULL;
+ return retval;
+}
+
void
zip_member_finish (struct zip_member *zm)
{
- ds_clear (zm->errs);
- /* 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);
+ zm->decompressor->finish (zm);
+ fclose (zm->fp);
+ free (zm->error);
+ free (zm);
}
- */
- zip_member_unref (zm);
}
-
+struct zip_reader *
+zip_reader_ref (const struct zip_reader *zr_)
+{
+ struct zip_reader *zr = CONST_CAST (struct zip_reader *, zr_);
+ assert (zr->ref_cnt > 0);
+ zr->ref_cnt++;
+ return zr;
+}
/* Destroy the zip reader */
void
-zip_reader_destroy (struct zip_reader *zr)
+zip_reader_unref (struct zip_reader *zr)
{
- int i;
- if (zr == NULL)
+ if (zr == NULL)
+ return;
+ assert (zr->ref_cnt > 0);
+ if (--zr->ref_cnt)
return;
- fclose (zr->fr);
- free (zr->filename);
+ free (zr->file_name);
- for (i = 0; i < zr->n_members; ++i)
+ for (int 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)
fseeko (f, n, SEEK_CUR);
}
-/* Read N bytes from F, storing the result in X */
static void
get_bytes (FILE *f, void *x, size_t n)
{
- fread (x, 1, n, f);
+ if (!fread (x, n, 1, f))
+ memset (x, 0, n);
}
-/* Read a 32 bit value from F */
-static void
-get_u32 (FILE *f, uint32_t *v)
+static uint32_t
+get_u32 (FILE *f)
{
uint32_t x;
get_bytes (f, &x, sizeof x);
-#ifdef WORDS_BIGENDIAN
- *v = bswap_32 (x);
-#else
- *v = x;
-#endif
+ return le_to_native32 (x);
}
-/* Read a 16 bit value from F */
-static void
-get_u16 (FILE *f, uint16_t *v)
+static uint16_t
+get_u16 (FILE *f)
{
uint16_t x;
get_bytes (f, &x, sizeof x);
-#ifdef WORDS_BIGENDIAN
- *v = bswap_16 (x);
-#else
- *v = x;
-#endif
+ return le_to_native16 (x);
}
+static char * WARN_UNUSED_RESULT
+get_stream_error (FILE *f, const char *file_name)
+{
+ if (feof (f))
+ return xasprintf (_("%s: unexpected end of file"), file_name);
+ else if (ferror (f))
+ {
+ /* The particular error might not be in errno anymore. Try to find out
+ what the error was. */
+ errno = 0;
+ char x;
+ return (!fread (&x, 1, sizeof x, f) && errno
+ ? xasprintf (_("%s: I/O error reading Zip archive (%s)"),
+ file_name, strerror (errno))
+ : xasprintf (_("%s: I/O error reading Zip archive"), file_name));
+ }
+ else
+ return NULL;
+}
/* 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)
+static char * WARN_UNUSED_RESULT
+check_magic (FILE *f, const char *file_name, uint32_t expected)
{
- uint32_t magic;
-
- get_u32 (f, &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);
-
- return false;
- }
- return true;
+ uint32_t magic = get_u32 (f);
+ char *error = get_stream_error (f, file_name);
+ if (error)
+ return error;
+ else if (expected != magic)
+ return xasprintf (_("%s: corrupt archive at 0x%llx: "
+ "expected %#"PRIx32" but got %#"PRIx32),
+ file_name,
+ (long long int) ftello (f) - sizeof (uint32_t),
+ expected, magic);
+ else
+ return NULL;
}
int
zip_member_read (struct zip_member *zm, void *buf, size_t bytes)
{
- int bytes_read = 0;
-
- ds_clear (zm->errs);
-
- if ( bytes > zm->bytes_unread)
+ if (bytes > zm->bytes_unread)
bytes = zm->bytes_unread;
+ if (!bytes)
+ return 0;
- bytes_read = decompressors[zm->compression].read (zm, buf, bytes);
- if ( bytes_read < 0)
+ int 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);
-
- uint16_t v, nlen, extralen;
- uint16_t gp, time, date;
-
- uint16_t clen, diskstart, iattr;
- uint32_t eattr;
- uint16_t comp_type;
-
- ds_clear (zr->errs);
-
- if ( ! check_magic (zr->fr, MAGIC_SOCD, zr->errs))
- return NULL;
-
- get_u16 (zr->fr, &v);
-
- get_u16 (zr->fr, &v);
- get_u16 (zr->fr, &gp);
- get_u16 (zr->fr, &comp_type);
-
- zm->compression = comp_code (zm, comp_type);
-
- get_u16 (zr->fr, &time);
- get_u16 (zr->fr, &date);
- get_u32 (zr->fr, &zm->expected_crc);
- get_u32 (zr->fr, &zm->comp_size);
- get_u32 (zr->fr, &zm->ucomp_size);
- get_u16 (zr->fr, &nlen);
- get_u16 (zr->fr, &extralen);
- get_u16 (zr->fr, &clen);
- get_u16 (zr->fr, &diskstart);
- get_u16 (zr->fr, &iattr);
- get_u32 (zr->fr, &eattr);
- get_u32 (zr->fr, &zm->offset);
+ struct zip_member *zm;
+ char *error = zip_member_open (zr, member_name, &zm);
+ if (error)
+ {
+ *datap = NULL;
+ *np = 0;
+ return error;
+ }
- zm->name = calloc (nlen + 1, 1);
- get_bytes (zr->fr, zm->name, nlen);
+ *datap = xmalloc (zm->ucomp_size);
+ *np = zm->ucomp_size;
- skip_bytes (zr->fr, extralen);
-
- zr->members[zr->nm++] = zm;
+ uint8_t *data = *datap;
+ while (zm->bytes_unread)
+ if (zip_member_read (zm, data + (zm->ucomp_size - zm->bytes_unread),
+ zm->bytes_unread) == -1)
+ {
+ char *error = zip_member_steal_error (zm);
+ zip_member_finish (zm);
+ free (*datap);
+ *datap = NULL;
+ *np = 0;
+ return error;
+ }
- zm->fp = fopen (zr->filename, "r");
- zm->ref_cnt = 1;
- zm->errs = zr->errs;
+ zip_member_finish (zm);
+ return NULL;
+}
- return zm;
+/* 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 char * WARN_UNUSED_RESULT
+zip_header_read_next (FILE *file, const char *file_name,
+ struct zip_entry *ze)
+{
+ char *error = check_magic (file, file_name, MAGIC_SOCD);
+ if (error)
+ return error;
+
+ get_u16 (file); /* v */
+ get_u16 (file); /* v */
+ get_u16 (file); /* gp */
+ get_u16 (file); /* comp_type */
+ get_u16 (file); /* time */
+ get_u16 (file); /* date */
+ get_u32 (file); /* expected_crc */
+ ze->comp_size = get_u32 (file);
+ ze->ucomp_size = get_u32 (file);
+ uint16_t nlen = get_u16 (file);
+ uint16_t extralen = get_u16 (file);
+ get_u16 (file); /* clen */
+ get_u16 (file); /* diskstart */
+ get_u16 (file); /* iattr */
+ get_u32 (file); /* eattr */
+ ze->offset = get_u32 (file);
+
+ error = get_stream_error (file, file_name);
+ if (error)
+ return error;
+
+ ze->name = xzalloc (nlen + 1);
+ get_bytes (file, ze->name, nlen);
+ error = get_stream_error (file, file_name);
+ if (error)
+ return error;
+
+ skip_bytes (file, extralen);
+
+ return NULL;
}
-/* Create a reader from the zip called FILENAME */
-struct zip_reader *
-zip_reader_create (const char *filename, struct string *errs)
+/* Create a reader from the zip called FILE_NAME */
+char * WARN_UNUSED_RESULT
+zip_reader_create (const char *file_name, struct zip_reader **zrp)
{
- uint16_t disknum, total_members;
- off_t offset = 0;
- uint32_t central_dir_start, central_dir_length;
-
- struct zip_reader *zr = malloc (sizeof *zr);
- zr->errs = errs;
- if ( zr->errs)
- ds_init_empty (zr->errs);
+ *zrp = NULL;
- zr->nm = 0;
+ FILE *file = fopen (file_name, "rb");
+ if (!file)
+ return xasprintf (_("%s: open failed (%s)"), file_name, strerror (errno));
- zr->fr = fopen (filename, "r");
- if (NULL == zr->fr)
+ /* Check the Zip file magic. */
+ char *error = check_magic (file, file_name, MAGIC_LHDR);
+ if (error)
{
- ds_put_cstr (zr->errs, strerror (errno));
- free (zr);
- return NULL;
+ fclose (file);
+ return error;
}
- if ( ! check_magic (zr->fr, MAGIC_LHDR, zr->errs))
+ /* Find end of central directory record and read it. */
+ off_t offset = 0;
+ if (! find_eocd (file, &offset))
{
- fclose (zr->fr);
- free (zr);
- return NULL;
+ fclose (file);
+ return xasprintf (_("%s: cannot find central directory"), file_name);
}
-
- if ( ! find_eocd (zr->fr, &offset))
+ if (0 != fseeko (file, offset, SEEK_SET))
{
- ds_put_format (zr->errs, _("Cannot find central directory"));
- fclose (zr->fr);
- free (zr);
- return NULL;
+ error = xasprintf (_("%s: seek failed (%s)"),
+ file_name, strerror (errno));
+ fclose (file);
+ return error;
}
-
- if ( 0 != fseeko (zr->fr, offset, SEEK_SET))
+ error = check_magic (file, file_name, MAGIC_EOCD);
+ if (error)
{
- const char *mm = strerror (errno);
- ds_put_format (zr->errs, _("Failed to seek to end of central directory record: %s"), mm);
- fclose (zr->fr);
- free (zr);
- return NULL;
+ fclose (file);
+ return error;
+ }
+ get_u16 (file); /* disknum */
+ get_u16 (file); /* disknum */
+ uint16_t n_members = get_u16 (file);
+ get_u16 (file); /* total_members */
+ get_u32 (file); /* central_dir_length */
+ uint32_t central_dir_start = get_u32 (file);
+ error = get_stream_error (file, file_name);
+ if (error)
+ {
+ fclose (file);
+ return error;
}
-
- if ( ! check_magic (zr->fr, MAGIC_EOCD, zr->errs))
+ /* Read central directory. */
+ if (0 != fseeko (file, central_dir_start, SEEK_SET))
{
- fclose (zr->fr);
- free (zr);
+ error = xasprintf (_("%s: seek failed (%s)"),
+ file_name, strerror (errno));
+ fclose (file);
return NULL;
}
-
- get_u16 (zr->fr, &disknum);
- get_u16 (zr->fr, &disknum);
-
- get_u16 (zr->fr, &zr->n_members);
- get_u16 (zr->fr, &total_members);
-
- get_u32 (zr->fr, ¢ral_dir_length);
- get_u32 (zr->fr, ¢ral_dir_start);
- if ( 0 != fseeko (zr->fr, central_dir_start, SEEK_SET))
+ struct zip_reader *zr = XZALLOC (struct zip_reader);
+ zr->ref_cnt = 1;
+ zr->file_name = xstrdup (file_name);
+ zr->entries = xcalloc (n_members, sizeof *zr->entries);
+ for (int i = 0; i < n_members; i++)
{
- const char *mm = strerror (errno);
- ds_put_format (zr->errs, _("Failed to seek to central directory: %s"), mm);
- fclose (zr->fr);
- free (zr);
- return NULL;
+ error = zip_header_read_next (file, file_name,
+ &zr->entries[zr->n_entries]);
+ if (error)
+ {
+ fclose (file);
+ zip_reader_unref (zr);
+ return error;
+ }
+ zr->n_entries++;
}
- zr->members = calloc (zr->n_members, sizeof (*zr->members));
+ fclose (file);
- zr->filename = strdup (filename);
+ *zrp = zr;
+ return NULL;
+}
- 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)
+char * WARN_UNUSED_RESULT
+zip_member_open (struct zip_reader *zr, const char *member,
+ struct zip_member **zmp)
{
- uint16_t v, nlen, extra_len;
- uint16_t gp, comp_type, time, date;
- uint32_t ucomp_size, comp_size;
-
- uint32_t crc;
-
- 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] = zip_header_read_next (zr);
- 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))
+ *zmp = NULL;
+
+ struct zip_entry *ze = zip_entry_find (zr, member);
+ if (ze == NULL)
+ return xasprintf (_("%s: unknown member \"%s\""),
+ zr->file_name, member);
+
+ FILE *fp = fopen (zr->file_name, "rb");
+ if (!fp)
+ return xasprintf ( _("%s: open failed (%s)"),
+ zr->file_name, strerror (errno));
+
+ 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->aux = NULL;
+ zm->error = NULL;
+
+ char *error;
+ if (0 != fseeko (zm->fp, zm->offset, SEEK_SET))
{
- const char *mm = strerror (errno);
- ds_put_format (zm->errs, _("Failed to seek to start of member `%s': %s"), zm->name, mm);
- return NULL;
+ error = xasprintf (_("%s: seek failed (%s)"),
+ ze->name, strerror (errno));
+ goto error;
}
- if ( ! check_magic (zm->fp, MAGIC_LHDR, zr->errs))
+ error = check_magic (zm->fp, zr->file_name, MAGIC_LHDR);
+ if (error)
+ goto error;
+
+ get_u16 (zm->fp); /* v */
+ get_u16 (zm->fp); /* gp */
+ uint16_t comp_type = get_u16 (zm->fp);
+ zm->decompressor = get_decompressor (comp_type);
+ if (!zm->decompressor)
{
- return NULL;
+ error = xasprintf (_("%s: member \"%s\" has unknown compression "
+ "type %"PRIu16),
+ zr->file_name, zm->member_name, comp_type);
+ goto error;
}
-
- get_u16 (zm->fp, &v);
- get_u16 (zm->fp, &gp);
- get_u16 (zm->fp, &comp_type);
- zm->compression = comp_code (zm, comp_type);
- get_u16 (zm->fp, &time);
- get_u16 (zm->fp, &date);
- get_u32 (zm->fp, &crc);
- get_u32 (zm->fp, &comp_size);
-
- get_u32 (zm->fp, &ucomp_size);
- get_u16 (zm->fp, &nlen);
- get_u16 (zm->fp, &extra_len);
-
- name = calloc (nlen + 1, sizeof (char));
-
+ get_u16 (zm->fp); /* time */
+ get_u16 (zm->fp); /* date */
+ get_u32 (zm->fp); /* crc */
+ get_u32 (zm->fp); /* comp_size */
+ get_u32 (zm->fp); /* ucomp_size */
+ uint16_t nlen = get_u16 (zm->fp);
+ uint16_t extra_len = get_u16 (zm->fp);
+ error = get_stream_error (zm->fp, zr->file_name);
+ if (error)
+ goto error;
+
+ char *name = xzalloc (nlen + 1);
get_bytes (zm->fp, name, nlen);
-
- skip_bytes (zm->fp, extra_len);
-
- if (strcmp (name, zm->name) != 0)
+ error = get_stream_error (zm->fp, zr->file_name);
+ if (error)
+ goto error;
+ if (strcmp (name, ze->name) != 0)
{
- ds_put_format (zm->errs,
- _("Name mismatch in zip archive. Central directory says `%s'; local file header says `%s'"),
- zm->name, name);
+ error = xasprintf (_("%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 ( ! decompressors[zm->compression].init (zm) )
- return NULL;
-
- return zm;
-}
-
-void
-zip_member_ref (struct zip_member *zm)
-{
- zm->ref_cnt++;
-}
-
-
+ skip_bytes (zm->fp, extra_len);
+ error = zm->decompressor->init (zm);
+ if (error)
+ goto error;
-void
-zip_member_unref (struct zip_member *zm)
-{
- if ( zm == NULL)
- return;
+ *zmp = zm;
+ return NULL;
- if (--zm->ref_cnt == 0)
- {
- decompressors[zm->compression].finish (zm);
- if (zm->fp)
- fclose (zm->fp);
- free (zm->name);
- free (zm);
- }
+error:
+ fclose (zm->fp);
+ free (zm->file_name);
+ free (zm->member_name);
+ free (zm);
+ return error;
}
-
\f
static bool probe_magic (FILE *fp, uint32_t magic, off_t start, off_t stop, off_t *off);
const uint32_t magic = MAGIC_EOCD;
bool found = false;
- /* The magic cannot be more than 22 bytes from the end of the file,
+ /* The magic cannot be more than 22 bytes from the end of the file,
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;
}
start = ftello (fp);
stop = start + sizeof (magic);
- do
+ do
{
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;
+ return false;
}
for (i = 0; i < 4 ; ++i)
do
{
- fread (&byte, 1, 1, fp);
+ 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)
+{
+ size_t bytes_read = fread (buf, 1, n, zm->fp);
+ if (!bytes_read && !zm->error)
+ zm->error = get_stream_error (zm->fp, zm->file_name);
+ return bytes_read;
+}
+
+static char *
+stored_init (struct zip_member *zm UNUSED)
+{
+ return NULL;
+}
+
+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 char *
+inflate_init (struct zip_member *zm)
+{
+ int r;
+ struct inflator *inf = XZALLOC (struct inflator);
+
+ 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)
+ return xasprintf (_("%s: cannot initialize inflator (%s)"),
+ zm->file_name, zError (r));
+
+ zm->aux = inf;
+
+ return NULL;
+}
+
+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);
+ if (!bytes_read && !zm->error)
+ {
+ zm->error = get_stream_error (zm->fp, zm->file_name);
+ return -1;
+ }
+
+ 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;
+ }
+
+ if (!zm->error)
+ zm->error = xasprintf (_("%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};