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-rw-r--r--cpukit/libmisc/untar/untar.c384
1 files changed, 384 insertions, 0 deletions
diff --git a/cpukit/libmisc/untar/untar.c b/cpukit/libmisc/untar/untar.c
new file mode 100644
index 0000000000..2c5c8e9cf3
--- /dev/null
+++ b/cpukit/libmisc/untar/untar.c
@@ -0,0 +1,384 @@
+/* FIXME:
+ * 1. Symbolic links are not created.
+ * 2. Untar_FromMemory uses FILE *fp.
+ * 3. How to determine end of archive?
+ *
+ * Written by: Jake Janovetz <janovetz@tempest.ece.uiuc.edu>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ *
+ * $Id$
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <rtems/untar.h>
+#include <rtems/bspIo.h>
+
+
+/**************************************************************************
+ * TAR file format:
+ *
+ * Offset Length Contents
+ * 0 100 bytes File name ('\0' terminated, 99 maxmum length)
+ * 100 8 bytes File mode (in octal ascii)
+ * 108 8 bytes User ID (in octal ascii)
+ * 116 8 bytes Group ID (in octal ascii)
+ * 124 12 bytes File size (s) (in octal ascii)
+ * 136 12 bytes Modify time (in octal ascii)
+ * 148 8 bytes Header checksum (in octal ascii)
+ * 156 1 bytes Link flag
+ * 157 100 bytes Linkname ('\0' terminated, 99 maxmum length)
+ * 257 8 bytes Magic PAX ("ustar\0" + 2 bytes padding)
+ * 257 8 bytes Magic GNU tar ("ustar \0")
+ * 265 32 bytes User name ('\0' terminated, 31 maxmum length)
+ * 297 32 bytes Group name ('\0' terminated, 31 maxmum length)
+ * 329 8 bytes Major device ID (in octal ascii)
+ * 337 8 bytes Minor device ID (in octal ascii)
+ * 345 155 bytes Prefix
+ * 512 (s+p)bytes File contents (s+p) := (((s) + 511) & ~511),
+ * round up to 512 bytes
+ *
+ * Checksum:
+ * int i, sum;
+ * char* header = tar_header_pointer;
+ * sum = 0;
+ * for(i = 0; i < 512; i++)
+ * sum += 0xFF & header[i];
+ *************************************************************************/
+
+#define MAX_NAME_FIELD_SIZE 99
+
+#define MIN(a,b) ((a)>(b)?(b):(a))
+
+
+/**************************************************************************
+ * This converts octal ASCII number representations into an
+ * unsigned long. Only support 32-bit numbers for now.
+ *************************************************************************/
+unsigned long
+_rtems_octal2ulong(
+ const char *octascii,
+ size_t len
+)
+{
+ size_t i;
+ unsigned long num;
+
+ num = 0;
+ for (i=0; i < len; i++)
+ {
+ if ((octascii[i] < '0') || (octascii[i] > '9'))
+ {
+ continue;
+ }
+ num = num * 8 + ((unsigned long)(octascii[i] - '0'));
+ }
+ return(num);
+}
+
+
+/**************************************************************************
+ * Function: Untar_FromMemory *
+ **************************************************************************
+ * Description: *
+ * *
+ * This is a simple subroutine used to rip links, directories, and *
+ * files out of a block of memory. *
+ * *
+ * *
+ * Inputs: *
+ * *
+ * void * tar_buf - Pointer to TAR buffer. *
+ * size_t size - Length of TAR buffer. *
+ * *
+ * *
+ * Output: *
+ * *
+ * int - UNTAR_SUCCESSFUL (0) on successful completion. *
+ * UNTAR_INVALID_CHECKSUM for an invalid header checksum. *
+ * UNTAR_INVALID_HEADER for an invalid header. *
+ * *
+ **************************************************************************/
+int
+Untar_FromMemory(
+ void *tar_buf,
+ size_t size
+)
+{
+ FILE *fp;
+ const char *tar_ptr = (const char *)tar_buf;
+ const char *bufr;
+ size_t n;
+ char fname[100];
+ char linkname[100];
+ int sum;
+ int hdr_chksum;
+ int retval;
+ unsigned long ptr;
+ unsigned long i;
+ unsigned long nblocks;
+ unsigned long file_size;
+ unsigned char linkflag;
+
+
+ ptr = 0;
+ while (1)
+ {
+ if (ptr + 512 > size)
+ {
+ retval = UNTAR_SUCCESSFUL;
+ break;
+ }
+
+ /* Read the header */
+ bufr = &tar_ptr[ptr];
+ ptr += 512;
+ if (strncmp(&bufr[257], "ustar", 5))
+ {
+ retval = UNTAR_SUCCESSFUL;
+ break;
+ }
+
+ strncpy(fname, bufr, MAX_NAME_FIELD_SIZE);
+ fname[MAX_NAME_FIELD_SIZE] = '\0';
+
+ linkflag = bufr[156];
+ file_size = _rtems_octal2ulong(&bufr[124], 12);
+
+ /******************************************************************
+ * Compute the TAR checksum and check with the value in
+ * the archive. The checksum is computed over the entire
+ * header, but the checksum field is substituted with blanks.
+ ******************************************************************/
+ hdr_chksum = _rtems_octal2ulong(&bufr[148], 8);
+ sum = _rtems_tar_header_checksum(bufr);
+
+ if (sum != hdr_chksum)
+ {
+ retval = UNTAR_INVALID_CHECKSUM;
+ break;
+ }
+
+
+ /******************************************************************
+ * We've decoded the header, now figure out what it contains and
+ * do something with it.
+ *****************************************************************/
+ if (linkflag == SYMTYPE)
+ {
+ strncpy(linkname, &bufr[157], MAX_NAME_FIELD_SIZE);
+ linkname[MAX_NAME_FIELD_SIZE] = '\0';
+ symlink(linkname, fname);
+ }
+ else if (linkflag == REGTYPE)
+ {
+ nblocks = (((file_size) + 511) & ~511) / 512;
+ if ((fp = fopen(fname, "w")) == NULL)
+ {
+ printk("Untar: failed to create file %s\n", fname);
+ ptr += 512 * nblocks;
+ }
+ else
+ {
+ unsigned long sizeToGo = file_size;
+ size_t len;
+
+ /***************************************************************
+ * Read out the data. There are nblocks of data where nblocks
+ * is the file_size rounded to the nearest 512-byte boundary.
+ **************************************************************/
+ for (i=0; i<nblocks; i++)
+ {
+ len = ((sizeToGo < 512L)?(sizeToGo):(512L));
+ n = fwrite(&tar_ptr[ptr], 1, len, fp);
+ if (n != len)
+ {
+ printk("untar: Error during write\n");
+ break;
+ }
+ ptr += 512;
+ sizeToGo -= n;
+ }
+ fclose(fp);
+ }
+ }
+ else if (linkflag == DIRTYPE)
+ {
+ mkdir(fname, S_IRWXU | S_IRWXG | S_IRWXO);
+ }
+ }
+
+ return(retval);
+}
+
+
+/**************************************************************************
+ * Function: Untar_FromFile *
+ **************************************************************************
+ * Description: *
+ * *
+ * This is a simple subroutine used to rip links, directories, and *
+ * files out of a TAR file. *
+ * *
+ * *
+ * Inputs: *
+ * *
+ * const char *tar_name - TAR filename. *
+ * *
+ * *
+ * Output: *
+ * *
+ * int - UNTAR_SUCCESSFUL (0) on successful completion. *
+ * UNTAR_INVALID_CHECKSUM for an invalid header checksum. *
+ * UNTAR_INVALID_HEADER for an invalid header. *
+ * *
+ **************************************************************************
+ * Change History: *
+ * 12/30/1998 - Creation (JWJ) *
+ *************************************************************************/
+int
+Untar_FromFile(
+ const char *tar_name
+)
+{
+ int fd;
+ char *bufr;
+ ssize_t n;
+ char fname[100];
+ char linkname[100];
+ int sum;
+ int hdr_chksum;
+ int retval;
+ unsigned long i;
+ unsigned long nblocks;
+ unsigned long size;
+ unsigned char linkflag;
+
+ retval = UNTAR_SUCCESSFUL;
+
+ if ((fd = open(tar_name, O_RDONLY)) < 0) {
+ return UNTAR_FAIL;
+ }
+
+ bufr = (char *)malloc(512);
+ if (bufr == NULL) {
+ return(UNTAR_FAIL);
+ }
+
+ while (1)
+ {
+ /* Read the header */
+ /* If the header read fails, we just consider it the end
+ of the tarfile. */
+ if ((n = read(fd, bufr, 512)) != 512)
+ {
+ break;
+ }
+
+ if (strncmp(&bufr[257], "ustar", 5))
+ {
+ break;
+ }
+
+ strncpy(fname, bufr, MAX_NAME_FIELD_SIZE);
+ fname[MAX_NAME_FIELD_SIZE] = '\0';
+
+ linkflag = bufr[156];
+ size = _rtems_octal2ulong(&bufr[124], 12);
+
+ /******************************************************************
+ * Compute the TAR checksum and check with the value in
+ * the archive. The checksum is computed over the entire
+ * header, but the checksum field is substituted with blanks.
+ ******************************************************************/
+ hdr_chksum = _rtems_octal2ulong(&bufr[148], 8);
+ sum = _rtems_tar_header_checksum(bufr);
+
+ if (sum != hdr_chksum)
+ {
+ retval = UNTAR_INVALID_CHECKSUM;
+ break;
+ }
+
+ /******************************************************************
+ * We've decoded the header, now figure out what it contains and
+ * do something with it.
+ *****************************************************************/
+ if (linkflag == SYMTYPE)
+ {
+ strncpy(linkname, &bufr[157], MAX_NAME_FIELD_SIZE);
+ linkname[MAX_NAME_FIELD_SIZE] = '\0';
+ symlink(linkname,fname);
+ }
+ else if (linkflag == REGTYPE)
+ {
+ int out_fd;
+
+ /******************************************************************
+ * Read out the data. There are nblocks of data where nblocks
+ * is the size rounded to the nearest 512-byte boundary.
+ *****************************************************************/
+ nblocks = (((size) + 511) & ~511) / 512;
+
+ if ((out_fd = creat(fname, 0644)) == -1)
+ {
+ for (i=0; i<nblocks; i++)
+ {
+ n = read(fd, bufr, 512);
+ }
+ }
+ else
+ {
+ for (i=0; i<nblocks; i++)
+ {
+ n = read(fd, bufr, 512);
+ n = MIN(n, size - i*512);
+ write(out_fd, bufr, n);
+ }
+ close(out_fd);
+ }
+ }
+ else if (linkflag == DIRTYPE)
+ {
+ mkdir(fname, S_IRWXU | S_IRWXG | S_IRWXO);
+ }
+ }
+ free(bufr);
+ close(fd);
+
+ return(retval);
+}
+
+/************************************************************************
+ * Compute the TAR checksum and check with the value in
+ * the archive. The checksum is computed over the entire
+ * header, but the checksum field is substituted with blanks.
+ ************************************************************************/
+int
+_rtems_tar_header_checksum(
+ const char *bufr
+)
+{
+ int i, sum;
+
+ sum = 0;
+ for (i=0; i<512; i++)
+ {
+ if ((i >= 148) && (i < 156))
+ sum += 0xff & ' ';
+ else
+ sum += 0xff & bufr[i];
+ }
+ return(sum);
+}
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