Files
commandergenius/project/jni/zzip/zzip/write.c
2010-11-29 12:44:44 +02:00

494 lines
16 KiB
C

/*
* The write-support in zziplib is not a full-flegded interface to the
* internals that zip file-header or zip archive an contain. It's
* primary use goes for savegames or transfer `pack-n-go` archives
* where time-stamps are rather unimportant. Here we can create an
* archive with filenames and their data portions, possibly obfuscated.
*
* DONT USE THIS
*
* The write support is supposed to be added directly into the main
* zziplib but it has not been implemented so far. It does however
* export the relevant call entries which will return EROFS (read-only
* filesystem) in case they are being called. That allows later programs
* to start up with earlier versions of zziplib that can only read ZIPs.
*
* Author:
* Guido Draheim <guidod@gmx.de>
*
* Copyright (c) 2003 Guido Draheim
* All rights reserved,
* use under the restrictions of the
* Lesser GNU General Public License
* or alternatively the restrictions
* of the Mozilla Public License 1.1
*/
#define _ZZIP_WRITE_SOURCE
#if defined DDDD || defined DDDDD || defined DDDDDD || defined DDDDDDD
#define _ZZIP_ENABLE_WRITE
#else /* per default, we add support for passthrough to posix write */
#define _ZZIP_POSIX_WRITE
#endif
#include <zzip/write.h> /* #includes <zzip/lib.h> */
#include <zzip/file.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdlib.h>
#include <ctype.h>
#ifdef ZZIP_HAVE_DIRECT_H
#include <direct.h>
#endif
#include <zzip/format.h>
#include <zzip/plugin.h>
#include <zzip/__debug.h>
#define ___ {
#define ____ }
#ifndef EROFS
# ifdef ENOSYS
#define EROFS ENOSYS
# else
#define EROFS EPERM
#endif
#endif
/* try real zlib routines for writing ? very experimental, very very ex... */
#ifndef _ZZIP_ENABLE_WRITE
#define _ZZIP_TRY 0
#else
#define _ZZIP_TRY 1
#endif
/* btw, is there any system that did define those different ? get away.. */
# ifndef S_IWGRP
# define S_IWGRP 00020
# endif
# ifndef S_IRWXO
# define S_IRWXO 00007
# endif
# ifdef ZZIP_HAVE_DIRECT_H
# define _mkdir(a,b) mkdir(a)
# else
# define _mkdir mkdir
# endif
/** create a new zip archive for writing
*
* This function will create a new zip archive. The returned parameter
* is a new "zzip dir" handle that should be saved to a variable so it
* can be used a base argument for => zzip_mkdir and => zzip_creat calls.
* The returned handle represents a zip central directory that must be
* saved to disk using => zzip_closedir.
*
* Returns null on error and sets errno. Remember, according to posix
* the => creat(2) call is equivalent to
open (path, O_WRONLY | O_CREAT | O_TRUNC, o_mode)
* so any previous zip-archive will be overwritten unconditionally and
* EEXIST errors from => mkdir(2) are suppressed. (fixme: delete the
* given subtree? like suggested by O_TRUNC? not done so far!)
*/
ZZIP_DIR *
zzip_dir_creat(zzip_char_t * name, int o_mode)
{
return zzip_dir_creat_ext_io(name, o_mode, 0, 0);
}
/** => zzip_dir_creat
*
* If the third argument "ext" has another special meaning here, as it
* is used to ensure that a given zip-file is created with the first entry
* of the ext-list appended as an extension unless the file-path already
* ends with a file-extension registered in the list. Therefore {"",0}
* matches all files and creates them as zip-archives under the given
* nonmodified name. (Some magic here? If the path ends in the path
* separator then make a real directory even in the presence of ext-list?)
*
* This function is not yet implemented, check for #def ZZIP_NO_CREAT
* Write-support will extend => zzip_closedir with semantics to finalize the
* zip-archive by writing the zip-trailer and closing the archive file.
*/
ZZIP_DIR *
zzip_dir_creat_ext_io(zzip_char_t * name, int o_mode,
zzip_strings_t * ext, zzip_plugin_io_t io)
{
if (! io)
io = zzip_get_default_io();
if (io != zzip_get_default_io())
{
/* the current io-structure does not contain a "write" entry,
* and therefore this parameter is useless. Anyone to expect
* some behavior should be warned, so here we let the function
* fail bluntly - and leaving the recovery to the application
*/
errno = EINVAL;
return 0;
}
if (! _ZZIP_TRY)
{
/* not implemented - however, we respect that a null argument to
* zzip_mkdir and zzip_creat works, so we silently still do the mkdir
*/
if (! _mkdir(name, o_mode) || errno == EEXIST)
errno = EROFS;
return 0;
} else
{
# define MAX_EXT_LEN 10
ZZIP_DIR *dir = zzip_dir_alloc(ext);
int name_len = strlen(name);
dir->realname = malloc(name_len + MAX_EXT_LEN);
if (! dir->realname)
goto error;
memcpy(dir->realname, name, name_len + 1);
___ int fd =
__zzip_try_open(dir->realname, O_EXCL | O_TRUNC | O_WRONLY, ext,
io);
if (fd != -1)
{ dir->fd = fd; return dir; }
___ zzip_strings_t *exx = ext;
int exx_len;
for (; *exx; exx++)
{
if ((exx_len = strlen(*exx) + 1) <= name_len &&
! memcmp(dir->realname + (name_len - exx_len), *exx, exx_len))
break; /* keep unmodified */
exx++;
if (*exx)
continue;
if (! (exx_len = strlen(*exx)) || exx_len >= MAX_EXT_LEN)
break;
memcpy(dir->realname + name_len, exx, exx_len); /* append! */
}
____;
fd = io->fd.open(dir->realname, O_CREAT | O_TRUNC | O_WRONLY, o_mode);
dir->realname[name_len] = '\0'; /* keep ummodified */
if (fd != -1)
{ dir->fd = fd; return dir; }
error:
zzip_dir_free(dir);
return 0;
____;
}
}
/** create a new archive area for writing
*
* This function will create a new archive area. This may either be a
* a new zip archive or a new directory in the filesystem. The returned
* parameter is a new "zzip dir" handle that should be saved to a variable
* so it can be used a base argument for => zzip_file_mkdir and
* => zzip_file_creat calls. The returned handle wraps both possibilities,
* it can be representing a zip central directory that must be
* saved to disk using => zzip_closedir or it is just a handle for the
* name of the real directory that still must be run through
* => zzip_closedir to release the wrapper around the directory name.
*
* The magic is pushed through the o_mode argument. Using a mode that
* has no group-write bit set (S_IWGRP = 0040) then the file is
* created as a zip directory. Note that this is unabridged of any
* umask value in the system where the argument to this function could
* be 0775 but with an umask of 0755 it turns out as 0755 for a real
* directory. Using 0755 directly would not create it as a real directory
* but as a zip archive handle.
*
* This function is not yet implemented, check for #def ZZIP_NO_CREAT
* Write-support will extend => zzip_closedir with semantics to finalize the
* zip-archive by writing the zip-trailer and closing the archive file.
*
* Returns null on error and sets errno. Remember, according to posix
* the => creat(2) call is equivalent to
open (path, O_WRONLY | O_CREAT | O_TRUNC, o_mode)
* so any previous zip-archive will be overwritten unconditionally and
* EEXIST errors from => mkdir(2) are suppressed. (fixme: delete the
* given subtree? like suggested by O_TRUNC? not done so far!)
*/
ZZIP_DIR *
zzip_createdir(zzip_char_t * name, int o_mode)
{
if (o_mode & S_IWGRP)
{
if (-1 == _mkdir(name, o_mode) && errno != EEXIST) /* fail */
return 0;
return zzip_opendir(name);
} else
return zzip_dir_creat(name, o_mode);
}
/** => zzip_file_creat also: mkdir(2), creat(2), zzip_dir_creat
*
* This function has an additional primary argument over the posix
* mkdir(2) - if it is null then this function behaves just like
* posix mkdir(2). The zzip_dir argument can be set to the result
* of a => zzip_createdir which allows for some magic that the
* given directory name is created as an entry in the zip archive.
*
* If the given dir name argument is not within the basepath of
* the zip central directory then a real directory is created.
* Any EEXIST errors are not suppressed unlike with => zzip_createdir
*
* Standard usage accepts a global/threaded/modular ZZIP_DIR pointer
* for all zip archive operations like in:
ZZIP_DIR* zip = zzip_createdir (sysconfpath, 0755, zip);
zzip_file_mkdir (zip, filepath[i], 0755);
ZZIP_FILE* file = zzip_file_creat (zip, filename[i], 0644);
zzip_write (file, buf, len);
zzip_close (file); file = 0;
zzip_closedir (zip); zip = 0;
*
* compare with => zzip_mkdir inline macro which allows to
* collapse the examples script to
#define zzip_savefile myproject_saveconfig
#include <zzip/zzip.h>
ZZIP_DIR* zzip_savefile = zzip_createdir (sysconfpath, 0755);
zzip_mkdir (filepath[i], 0755);
ZZIP_FILE* file = zzip_creat(filepath[i], 0644);
zzip_write (file, buf, len);
zzip_close (file); file = 0;
zzip_closedir (zip_savefile);
*/
int
zzip_file_mkdir(ZZIP_DIR * dir, zzip_char_t * name, int o_mode)
{
if (! dir)
return _mkdir(name, o_mode);
if (! _ZZIP_TRY)
{ /* not implemented */
errno = EROFS;
return -1;
} else
{
errno = EROFS;
return -1;
}
}
/** start next file entry in a zip archive
*
* This function will create a new file within a zzip archive, the
* one given as the primary argument and additionally to the posix
* creat(2) - just like zzip_mkdir has an additional argument over
* the posix mkdir(2) spec. For this function the primary parameter
* can be null as well thereby creating a real file instead of a new
* one inside the zip-archive otherwise given. If the primary parameter is
* not null but wraps a real directory then all new files are also real.
*
* This function is not yet implemented, check for #def ZZIP_NO_CREAT
*
* Returns NULL on an error setting errno, and opening a file _within_
* a zip archive using O_RDONLY (and similar stuff) will surely lead to
* an error.
*/
ZZIP_FILE *
zzip_file_creat(ZZIP_DIR * dir, zzip_char_t * name, int o_mode)
{
if (! dir)
return zzip_open(name, o_mode);
if (! _ZZIP_TRY)
{ /* not implemented */
errno = EROFS;
return 0;
} else
{
errno = EROFS;
return 0;
}
}
/** write to zzip storage also: write(2), zlib(3)
*
* This function will write data to a file descriptor. If the file
* descriptor represents a real file then it will be forwarded to
* call posix => write(2) directly. If it is a descriptor for a
* file within a zip directory then the data will be "deflated"
* using => zlib(3) and appended to the zip archive file.
*/
zzip_ssize_t
zzip_write(ZZIP_FILE * file, const void *ptr, zzip_size_t len)
{
if (zzip_file_real(file))
return write(zzip_realfd(file), ptr, len);
else
return zzip_file_write(file, ptr, len);
}
/** => zzip_write also: zzip_file_creat
*
* This function will write data to a file descriptor inside a zip
* archive. The data will be "deflated" using => zlib(3) compression
* and appended to the end of the zip archive file. Only one file
* descriptor may be open per zzip_dir archive handle (fifo-like).
*
* This function is not yet implemented, check for #def ZZIP_NO_CREAT
* It returns immediately -1 and sets errno=EROFS for indication.
*/
zzip_ssize_t
zzip_file_write(ZZIP_FILE * file, const void *ptr, zzip_size_t len)
{
if (! _ZZIP_TRY)
{ /* not implemented */
errno = EROFS;
return -1;
} else
{
/* add calls to zlib here... */
errno = EROFS;
return -1;
}
}
/** => zzip_write
* This function is the stdc variant for writing and the arguments
* are forwarded to => zzip_write - the return value is floored to
* null as for STDC spec but there is no zzip_ferror call so far
* for the zziplib (later? is it actually needed?).
*
* This function is not yet implemented, check for #def ZZIP_NO_CREAT
* Write-support extends => zzip_close with semantics to write out a
* file-trailer to the zip-archive leaving a name/offset marker in
* the (still-open) ZZIP_DIR handle.
*/
zzip_size_t
zzip_fwrite(const void *ptr, zzip_size_t len, zzip_size_t multiply,
ZZIP_FILE * file)
{
zzip_ssize_t value = zzip_write(file, ptr, len * multiply);
if (value == -1)
value = 0;
return (zzip_size_t) value;
}
#if 0 /* pure documentation */
/** create a zipped file/directory also: zzip_dir_creat, mkdir(2)
*
* This function creates a directory entry in the default zip-archive.
* If you did not specify a "#define zzip_savefile somevar"
* then the default zip-archive is null and all directories are
* created as real directories in the filesystem. This function is
* really a preprocessor macro or preferably an inline function
* around => zzip_file_mkdir, there is no such symbol generated
* into the library. The prototype is modelled after the posix
* => mkdir(2) call.
#ifndef zzip_savefile
#define zzip_savefile 0
#endif
#define zzip_mkdir(name,mode) \ -
zzip_file_mkdir(zzip_savefile,name,mode)
*
*/
int inline
zzip_mkdir(zzip_char_t * name, int o_mode)
{
return zzip_file_creat(zzip_savefile, name, mode);
}
#endif
#if 0 /* pure documentation */
/** => zzip_mkdir also: creat(2), zzip_start
*
* This function creates a file in the default zip-archive.
* If you did not specify a "#define zzip_savefile somevar"
* then the default zip-archive is null and all files are created
* as real files. This function is really a preprocessor macro
* or preferably an inline function around => zzip_file_creat,
* there is no such symbol generated into the library. The prototype
* is modelled after the posix => creat(2) call.
#ifndef zzip_savefile
#define zzip_savefile 0
#endif
#define zzip_creat(name,mode) \ -
zzip_file_creat(zzip_savefile,name,mode)
*/
ZZIP_FILE *inline
zzip_creat(zzip_char_t * name, int o_mode)
{
return zzip_file_creat(zzip_savefile, name, mode);
}
#endif
#if 0 /* pure documentation */
/** start writing to the magic zzip_savefile also: zzip_creat, zzip_write
*
* open a zip archive for writing via the magic zzip_savefile macro
* variable. The name and mode are given to => zzip_createdir and
* the result is stored into => zzip_savefile - if the => zzip_savefile
* did already have a zzip_dir handle then it is automatically
* finalized with => zzip_sync and the handle closed and the
* zzip_savefile variable reused for the new zip archive just started
* with this call. - This function is really a preprocessor macro
* or preferably an inline function around => zzip_dir_create, there
* is no such symbol generated into the library.
#ifndef zzip_savefile
#define zzip_savefile 0
#endif
#define zzip_start(name,mode,ext) \ -
{ if (zzip_savefile) zzip_closedir(zzip_savefile); \ -
zzip_savefile = zzip_createdir(name,mode,ext); }
* This function returns null on error or a zzip_dir handle on
* success. It is perfectly okay to continue with a null in the
* zzip_savefile variable since it makes subsequent calls to
* => zzip_creat and => zzip_mkdir to run as => creat(2) / => mkdir(2)
* on the real filesystem.
*/
void inline
zzip_mkfifo(zzip_char_t * name, int o_mode)
{
if (zzip_savefile)
zzip_closedir(zzip_savefile);
zzip_savefile = zzip_createdir(name, o_mode);
}
#endif
#if 0 /* pure documentation */
/** => zzip_mkfifo also: zzip_closedir, sync(2)
*
* finalize a zip archive thereby writing the central directory to
* the end of the file. If it was a real directory then we do just
* nothing - even that the prototype of the call itself is modelled
* to be similar to the posix => sync(2) call. This function is
* really a preprocessor macro or preferably an inline function
* around => zzip_closedir, there is no such symbol generated
* into the library.
#ifndef zzip_savefile
#define zzip_savefile 0
#endif
#define zzip_sync(name,mode) \ -
{ zzip_closedir(zzip_savefile); zzip_savefile = 0; }
*
*/
void inline
zzip_sync(void)
{
zzip_closedir(zzip_savefile);
zzip_savefile = 0;
}
#endif
/*
* Local variables:
* c-file-style: "stroustrup"
* End:
*/