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mxml/zipc.c

857 lines
23 KiB

/*
* Implementation of ZIP container mini-library.
*
* https://github.com/michaelrsweet/zipc
*
* Copyright 2017 by Michael R Sweet.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Include necessary headers...
*/
#include "zipc.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include <sys/time.h>
#include <zlib.h>
/*
* Local constants...
*/
#define ZIPC_LOCAL_HEADER 0x04034b50 /* Start of a local file header */
#define ZIPC_DIR_HEADER 0x02014b50 /* File header in central directory */
#define ZIPC_END_RECORD 0x06054b50 /* End of central directory record */
#define ZIPC_MADE_BY 0x031e /* Version made by UNIX using zip 2.0 */
#define ZIPC_DIR_VERSION 0x000a /* Version needed: 1.0 */
#define ZIPC_FILE_VERSION 0x0014 /* Version needed: 2.0 */
#define ZIPC_FLAG_CMAX 0x0002 /* Maximum compression */
#define ZIPC_FLAG_DATA 0x0008 /* Length and CRC-32 fields follow data */
#define ZIPC_COMP_STORE 0 /* No compression */
#define ZIPC_COMP_DEFLATE 8 /* Deflate compression */
#define ZIPC_INTERNAL_BIN 0x0000 /* Internal attributes = binary */
#define ZIPC_INTERNAL_TEXT 0x0001 /* Internal attributes = text */
#define ZIPC_EXTERNAL_DIR 0x41ed0010 /* External attributes = directory */
#define ZIPC_EXTERNAL_FILE 0x81a40000 /* External attributes = file */
/*
* Local types...
*/
struct _zipc_s
{
FILE *fp; /* ZIP file */
const char *error; /* Last error message */
size_t alloc_files, /* Allocated file entries in ZIP */
num_files; /* Number of file entries in ZIP */
zipc_file_t *files; /* File entries in ZIP */
z_stream stream; /* Deflate stream for current file */
unsigned int modtime; /* MS-DOS modification date/time */
char buffer[16384]; /* Deflate output buffer */
};
struct _zipc_file_s
{
zipc_t *zc; /* ZIP container */
char filename[256]; /* File/directory name */
unsigned short flags; /* General purpose bit flags */
unsigned short method; /* Compression method */
unsigned int crc32; /* 32-bit CRC */
size_t compressed_size; /* Size of file (compressed) */
size_t uncompressed_size; /* Size of file (uncompressed) */
size_t offset; /* Offset of this entry in file */
unsigned short internal_attrs; /* Internal attributes */
unsigned int external_attrs; /* External attributes */
};
/*
* Local functions...
*/
static zipc_file_t *zipc_add_file(zipc_t *zc, const char *filename, int compression);
static int zipc_write(zipc_t *zc, const void *buffer, size_t bytes);
static int zipc_write_dir_header(zipc_t *zc, zipc_file_t *zf);
static int zipc_write_local_header(zipc_t *zc, zipc_file_t *zf);
static int zipc_write_local_trailer(zipc_t *zc, zipc_file_t *zf);
static int zipc_write_u16(zipc_t *zc, unsigned value);
static int zipc_write_u32(zipc_t *zc, unsigned value);
/*
* 'zipcClose()' - Close a ZIP container, writing out the central directory.
*/
int /* O - 0 on success, -1 on error */
zipcClose(zipc_t *zc) /* I - ZIP container */
{
size_t i; /* Looping var */
zipc_file_t *zf; /* Current file */
long start, end; /* Central directory offsets */
int status = 0; /* Return status */
/*
* First write the central directory headers...
*/
start = ftell(zc->fp);
for (i = zc->num_files, zf = zc->files; i > 0; i --, zf ++)
status |= zipc_write_dir_header(zc, zf);
end = ftell(zc->fp);
/*
* Then write the end of central directory block...
*/
status |= zipc_write_u32(zc, ZIPC_END_RECORD);
status |= zipc_write_u16(zc, 0); /* Disk number */
status |= zipc_write_u16(zc, 0); /* Disk number containing directory */
status |= zipc_write_u16(zc, (unsigned)zc->num_files);
status |= zipc_write_u16(zc, (unsigned)zc->num_files);
status |= zipc_write_u32(zc, (unsigned)(end - start));
status |= zipc_write_u32(zc, (unsigned)start);
status |= zipc_write_u16(zc, 0); /* file comment length */
if (fclose(zc->fp))
status = -1;
if (zc->alloc_files)
free(zc->files);
free(zc);
return (status);
}
/*
* 'zipcCreateDirectory()' - Create a directory in a ZIP container.
*
* The "filename" value is the path within the ZIP container. Directories are
* separated by the forward slash ("/").
*/
int /* O - 0 on success, -1 on error */
zipcCreateDirectory(
zipc_t *zc, /* I - ZIP container */
const char *filename) /* I - Directory name */
{
zipc_file_t *zf = zipc_add_file(zc, filename, 0);
/* ZIP container file */
int status = 0; /* Return status */
if (zf)
{
char *end = zf->filename + strlen(zf->filename);
if (end > zf->filename && end < (zf->filename + sizeof(zf->filename) - 1) && end[-1] != '/')
*end = '/';
zf->crc32 = 0;
zf->external_attrs = ZIPC_EXTERNAL_DIR;
status |= zipc_write_local_header(zc, zf);
}
else
status = -1;
return (status);
}
/*
* 'zipcCreateFile()' - Create a ZIP container file.
*
* The "filename" value is the path within the ZIP container. Directories are
* separated by the forward slash ("/").
*
* The "compressed" value determines whether the file is compressed within the
* container.
*/
zipc_file_t * /* I - ZIP container file */
zipcCreateFile(
zipc_t *zc, /* I - ZIP container */
const char *filename, /* I - Filename in container */
int compressed) /* I - 0 for uncompressed, 1 for compressed */
{
/*
* Add the file and write the header...
*/
zipc_file_t *zf = zipc_add_file(zc, filename, compressed);
/* ZIP container file */
zf->external_attrs = ZIPC_EXTERNAL_FILE;
if (zipc_write_local_header(zc, zf))
return (NULL);
else
return (zf);
}
/*
* 'zipcCreateFileWithString()' - Add a file whose contents are a string.
*
* This function should be used for short ZIP container files like mimetype
* or container descriptions.
*
* Note: Files added this way are not compressed.
*/
int /* O - 0 on success, -1 on failure */
zipcCreateFileWithString(
zipc_t *zc, /* I - ZIP container */
const char *filename, /* I - Filename in container */
const char *contents) /* I - Contents of file */
{
zipc_file_t *zf = zipc_add_file(zc, filename, 0);
/* ZIP container file */
size_t len = strlen(contents); /* Length of contents */
int status = 0; /* Return status */
if (zf)
{
zf->uncompressed_size = len;
zf->compressed_size = len;
zf->crc32 = crc32(zf->crc32, (const Bytef *)contents, (unsigned)len);
zf->internal_attrs = ZIPC_INTERNAL_TEXT;
zf->external_attrs = ZIPC_EXTERNAL_FILE;
status |= zipc_write_local_header(zc, zf);
status |= zipc_write(zc, contents, len);
}
else
status = -1;
return (status);
}
/*
* 'zipcError()' - Return a message describing the last detected error.
*/
const char * /* O - Error string or NULL */
zipcError(zipc_t *zc) /* I - ZIP container */
{
return (zc ? zc->error : NULL);
}
/*
* 'zipcFileFinish()' - Finish writing to a file in a ZIP container.
*/
int /* O - 0 on success, -1 on error */
zipcFileFinish(zipc_file_t *zf) /* I - ZIP container file */
{
int status = 0; /* Return status */
zipc_t *zc = zf->zc; /* ZIP container */
if (zf->method != ZIPC_COMP_STORE)
{
int zstatus; /* Deflate status */
while ((zstatus = deflate(&zc->stream, Z_FINISH)) != Z_STREAM_END)
{
if (zstatus < Z_OK && zstatus != Z_BUF_ERROR)
{
zc->error = "Deflate failed.";
status = -1;
break;
}
status |= zipc_write(zf->zc, zc->buffer, (size_t)((char *)zc->stream.next_out - zc->buffer));
zf->compressed_size += (size_t)((char *)zc->stream.next_out - zc->buffer);
zc->stream.next_out = (Bytef *)zc->buffer;
zc->stream.avail_out = sizeof(zc->buffer);
}
if ((char *)zc->stream.next_out > zc->buffer)
{
status |= zipc_write(zf->zc, zc->buffer, (size_t)((char *)zc->stream.next_out - zc->buffer));
zf->compressed_size += (size_t)((char *)zc->stream.next_out - zc->buffer);
}
deflateEnd(&zc->stream);
}
status |= zipc_write_local_trailer(zc, zf);
return (status);
}
/*
* 'zipcFilePrintf()' - Write a formatted string to a file.
*
* The "zf" value is the one returned by the @link zipc_start_file@ function
* used to create the ZIP container file.
*
* The "format" value is a standard printf format string and is followed by
* any arguments needed by the string.
*/
int /* O - 0 on success, -1 on error */
zipcFilePrintf(zipc_file_t *zf, /* I - ZIP container file */
const char *format, /* I - Printf-style format string */
...) /* I - Additional arguments as needed */
{
char buffer[8192]; /* Format buffer */
va_list ap; /* Pointer to additional arguments */
va_start(ap, format);
if (vsnprintf(buffer, sizeof(buffer), format, ap) < 0)
{
zf->zc->error = strerror(errno);
va_end(ap);
return (-1);
}
va_end(ap);
zf->internal_attrs = ZIPC_INTERNAL_TEXT;
return (zipcFileWrite(zf, buffer, strlen(buffer)));
}
/*
* 'zipcFilePuts()' - Write a string to a file.
*
* The "zf" value is the one returned by the @link zipc_start_file@ function
* used to create the ZIP container file.
*
* The "s" value is literal string that is written to the file. No newline is
* added.
*/
int /* O - 0 on success, -1 on error */
zipcFilePuts(zipc_file_t *zf, /* I - ZIP container file */
const char *s) /* I - String to write */
{
zf->internal_attrs = ZIPC_INTERNAL_TEXT;
return (zipcFileWrite(zf, s, strlen(s)));
}
/*
* 'zipcFileWrite()' - Write data to a ZIP container file.
*
* The "zf" value is the one returned by the @link zipc_file_start@ function
* used to create the ZIP container file.
*
* The "data" value points to the bytes to be written.
*
* The "bytes" value specifies the number of bytes to write.
*/
int /* O - 0 on success, -1 on error */
zipcFileWrite(zipc_file_t *zf, /* I - ZIP container file */
const void *data, /* I - Data to write */
size_t bytes) /* I - Number of bytes to write */
{
int status = 0; /* Return status */
zipc_t *zc = zf->zc; /* ZIP container */
zf->uncompressed_size += bytes;
zf->crc32 = crc32(zf->crc32, (const Bytef *)data, (unsigned)bytes);
if (zf->method == ZIPC_COMP_STORE)
{
/*
* Store the contents as literal data...
*/
status = zipc_write(zc, data, bytes);
zf->compressed_size += bytes;
}
else
{
/*
* Deflate (compress) the contents...
*/
int zstatus; /* Deflate status */
zc->stream.next_in = (Bytef *)data;
zc->stream.avail_in = (unsigned)bytes;
while (zc->stream.avail_in > 0)
{
if (zc->stream.avail_out < (int)(sizeof(zc->buffer) / 8))
{
status |= zipc_write(zf->zc, zc->buffer, (size_t)((char *)zc->stream.next_out - zc->buffer));
zf->compressed_size += (size_t)((char *)zc->stream.next_out - zc->buffer);
zc->stream.next_out = (Bytef *)zc->buffer;
zc->stream.avail_out = sizeof(zc->buffer);
}
zstatus = deflate(&zc->stream, Z_NO_FLUSH);
if (zstatus < Z_OK && zstatus != Z_BUF_ERROR)
{
zc->error = "Deflate failed.";
status = -1;
break;
}
}
}
return (status);
}
/*
* 'zipcFileXMLPrintf()' - Write a formatted XML string to a file.
*
* The "zf" value is the one returned by the @link zipc_start_file@ function
* used to create the ZIP container file.
*
* The "format" value is a printf-style format string supporting "%d", "%s",
* and "%%" and is followed by any arguments needed by the string. Strings
* ("%s") are escaped as needed.
*/
int /* O - 0 on success, -1 on error */
zipcFileXMLPrintf(
zipc_file_t *zf, /* I - ZIP container file */
const char *format, /* I - Printf-style format string */
...) /* I - Additional arguments as needed */
{
int status = 0; /* Return status */
va_list ap; /* Pointer to additional arguments */
char buffer[65536], /* Buffer */
*bufend = buffer + sizeof(buffer) - 6,
/* End of buffer less "&quot;" */
*bufptr = buffer; /* Pointer into buffer */
const char *s; /* String pointer */
int d; /* Number */
va_start(ap, format);
while (*format && bufptr < bufend)
{
if (*format == '%')
{
format ++;
switch (*format)
{
case '%' : /* Substitute a single % */
format ++;
*bufptr++ = '%';
break;
case 'd' : /* Substitute a single integer */
format ++;
d = va_arg(ap, int);
snprintf(bufptr, bufend - bufptr, "%d", d);
bufptr += strlen(bufptr);
break;
case 's' : /* Substitute a single string */
format ++;
s = va_arg(ap, const char *);
while (*s && bufptr < bufend)
{
switch (*s)
{
case '&' : /* &amp; */
*bufptr++ = '&';
*bufptr++ = 'a';
*bufptr++ = 'm';
*bufptr++ = 'p';
*bufptr++ = ';';
break;
case '<' : /* &lt; */
*bufptr++ = '&';
*bufptr++ = 'l';
*bufptr++ = 't';
*bufptr++ = ';';
break;
case '>' : /* &gt; */
*bufptr++ = '&';
*bufptr++ = 'g';
*bufptr++ = 't';
*bufptr++ = ';';
break;
case '\"' : /* &quot; */
*bufptr++ = '&';
*bufptr++ = 'q';
*bufptr++ = 'u';
*bufptr++ = 'o';
*bufptr++ = 't';
*bufptr++ = ';';
break;
default :
*bufptr++ = *s;
break;
}
s ++;
}
if (*s)
{
format += strlen(format);
status = -1;
zf->zc->error = "Not enough memory to hold XML string.";
}
break;
default : /* Something else we don't support... */
format += strlen(format);
status = -1;
zf->zc->error = "Unsupported format character - only %%, %d, and %s are supported.";
break;
}
}
else
*bufptr++ = *format++;
}
va_end(ap);
if (*format)
{
status = -1;
zf->zc->error = "Not enough memory to hold XML string.";
}
if (bufptr > buffer)
{
zf->internal_attrs = ZIPC_INTERNAL_TEXT;
status |= zipcFileWrite(zf, buffer, (size_t)(bufptr - buffer));
}
return (status);
}
/*
* 'zipcOpen()' - Open a ZIP container.
*
* Currently the only supported "mode" value is "w" (write).
*/
zipc_t * /* O - ZIP container */
zipcOpen(const char *filename, /* I - Filename of container */
const char *mode) /* I - Open mode ("w") */
{
zipc_t *zc; /* ZIP container */
/*
* Only support write mode for now...
*/
if (strcmp(mode, "w"))
{
errno = EINVAL;
return (NULL);
}
/*
* Allocate memory...
*/
if ((zc = calloc(1, sizeof(zipc_t))) != NULL)
{
time_t curtime; /* Current timestamp */
struct tm *curdate; /* Current date/time */
/*
* Open the container file...
*/
if ((zc->fp = fopen(filename, "wb")) == NULL)
{
free(zc);
return (NULL);
}
/*
* Get the current date/time and convert it to the packed MS-DOS format:
*
* Bits Description
* ------ -----------
* 0-4 Seconds / 2 (0-29)
* 5-10 Minute (0-59)
* 11-15 Hour (0-23)
* 16-20 Day (1-31)
* 21-24 Month (1-12)
* 25-31 Years since 1980
*/
curtime = time(NULL);
curdate = localtime(&curtime);
zc->modtime = (unsigned)(curdate->tm_sec / 2) |
((unsigned)curdate->tm_min << 5) |
((unsigned)curdate->tm_hour << 11) |
((unsigned)curdate->tm_mday << 16) |
((unsigned)(curdate->tm_mon + 1) << 21) |
((unsigned)(curdate->tm_year - 80) << 25);
}
return (zc);
}
/*
* 'zipc_add_file()' - Add a file to the ZIP container.
*/
static zipc_file_t * /* O - New file */
zipc_add_file(zipc_t *zc, /* I - ZIP container */
const char *filename, /* I - Name of file in container */
int compression) /* I - 0 = uncompressed, 1 = compressed */
{
zipc_file_t *temp; /* File(s) */
if (zc->num_files >= zc->alloc_files)
{
/*
* Allocate more files...
*/
zc->alloc_files += 10;
if (!zc->files)
temp = malloc(zc->alloc_files * sizeof(zipc_file_t));
else
temp = realloc(zc->files, zc->alloc_files * sizeof(zipc_file_t));
if (!temp)
{
zc->error = strerror(errno);
return (NULL);
}
zc->files = temp;
}
temp = zc->files + zc->num_files;
zc->num_files ++;
memset(temp, 0, sizeof(zipc_file_t));
strncpy(temp->filename, filename, sizeof(temp->filename) - 1);
temp->zc = zc;
temp->crc32 = crc32(0, NULL, 0);
temp->offset = (size_t)ftell(zc->fp);
if (compression)
{
temp->flags = ZIPC_FLAG_CMAX;
temp->method = ZIPC_COMP_DEFLATE;
zc->stream.zalloc = (alloc_func)0;
zc->stream.zfree = (free_func)0;
zc->stream.opaque = (voidpf)0;
deflateInit2(&zc->stream, Z_BEST_COMPRESSION, Z_DEFLATED, -15, 8, Z_DEFAULT_STRATEGY);
zc->stream.next_out = (Bytef *)zc->buffer;
zc->stream.avail_out = sizeof(zc->buffer);
}
return (temp);
}
/*
* 'zipc_write()' - Write bytes to a ZIP container.
*/
static int /* I - 0 on success, -1 on error */
zipc_write(zipc_t *zc, /* I - ZIP container */
const void *buffer, /* I - Buffer to write */
size_t bytes) /* I - Number of bytes */
{
if (fwrite(buffer, bytes, 1, zc->fp))
return (0);
zc->error = strerror(ferror(zc->fp));
return (-1);
}
/*
* 'zipc_write_dir_header()' - Write a central directory file header.
*/
static int /* I - 0 on success, -1 on error */
zipc_write_dir_header(
zipc_t *zc, /* I - ZIP container */
zipc_file_t *zf) /* I - ZIP container file */
{
int status = 0; /* Return status */
size_t filenamelen = strlen(zf->filename);
/* Length of filename */
status |= zipc_write_u32(zc, ZIPC_DIR_HEADER);
status |= zipc_write_u16(zc, ZIPC_MADE_BY);
status |= zipc_write_u16(zc, zf->external_attrs == ZIPC_EXTERNAL_DIR ? ZIPC_DIR_VERSION : ZIPC_FILE_VERSION);
status |= zipc_write_u16(zc, zf->flags);
status |= zipc_write_u16(zc, zf->method);
status |= zipc_write_u32(zc, zc->modtime);
status |= zipc_write_u32(zc, zf->crc32);
status |= zipc_write_u32(zc, (unsigned)zf->compressed_size);
status |= zipc_write_u32(zc, (unsigned)zf->uncompressed_size);
status |= zipc_write_u16(zc, (unsigned)filenamelen);
status |= zipc_write_u16(zc, 0); /* extra field length */
status |= zipc_write_u16(zc, 0); /* comment length */
status |= zipc_write_u16(zc, 0); /* disk number start */
status |= zipc_write_u16(zc, zf->internal_attrs);
status |= zipc_write_u32(zc, zf->external_attrs);
status |= zipc_write_u32(zc, (unsigned)zf->offset);
status |= zipc_write(zc, zf->filename, filenamelen);
return (status);
}
/*
* 'zipc_write_local_header()' - Write a local file header.
*/
static int /* I - 0 on success, -1 on error */
zipc_write_local_header(
zipc_t *zc, /* I - ZIP container */
zipc_file_t *zf) /* I - ZIP container file */
{
int status = 0; /* Return status */
unsigned flags = zf->flags; /* General purpose flags */
size_t filenamelen = strlen(zf->filename);
/* Length of filename */
if (zf->uncompressed_size == 0 && zf->external_attrs != ZIPC_EXTERNAL_DIR)
flags |= ZIPC_FLAG_DATA;
status |= zipc_write_u32(zc, ZIPC_LOCAL_HEADER);
status |= zipc_write_u16(zc, zf->external_attrs == ZIPC_EXTERNAL_DIR ? ZIPC_DIR_VERSION : ZIPC_FILE_VERSION);
status |= zipc_write_u16(zc, flags);
status |= zipc_write_u16(zc, zf->method);
status |= zipc_write_u32(zc, zc->modtime);
status |= zipc_write_u32(zc, zf->uncompressed_size == 0 ? 0 : zf->crc32);
status |= zipc_write_u32(zc, (unsigned)zf->compressed_size);
status |= zipc_write_u32(zc, (unsigned)zf->uncompressed_size);
status |= zipc_write_u16(zc, (unsigned)filenamelen);
status |= zipc_write_u16(zc, 0); /* extra field length */
status |= zipc_write(zc, zf->filename, filenamelen);
return (status);
}
/*
* 'zipc_write_local_trailer()' - Write a local file trailer.
*/
static int /* I - 0 on success, -1 on error */
zipc_write_local_trailer(
zipc_t *zc, /* I - ZIP container */
zipc_file_t *zf) /* I - ZIP container file */
{
int status = 0; /* Return status */
status |= zipc_write_u32(zc, zf->crc32);
status |= zipc_write_u32(zc, (unsigned)zf->compressed_size);
status |= zipc_write_u32(zc, (unsigned)zf->uncompressed_size);
return (status);
}
/*
* 'zipc_write_u16()' - Write a 16-bit unsigned integer.
*/
static int /* I - 0 on success, -1 on error */
zipc_write_u16(zipc_t *zc, /* I - ZIP container */
unsigned value) /* I - Value to write */
{
unsigned char buffer[2]; /* Buffer */
buffer[0] = (unsigned char)value;
buffer[1] = (unsigned char)(value >> 8);
return (zipc_write(zc, buffer, sizeof(buffer)));
}
/*
* 'zipc_write_u32()' - Write a 32-bit unsigned integer.
*/
static int /* I - 0 on success, -1 on error */
zipc_write_u32(zipc_t *zc, /* I - ZIP container */
unsigned value) /* I - Value to write */
{
unsigned char buffer[4]; /* Buffer */
buffer[0] = (unsigned char)value;
buffer[1] = (unsigned char)(value >> 8);
buffer[2] = (unsigned char)(value >> 16);
buffer[3] = (unsigned char)(value >> 24);
return (zipc_write(zc, buffer, sizeof(buffer)));
}