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authorGlenn L McGrath <bug1@ihug.co.nz>2001-10-25 14:18:08 +0000
committerGlenn L McGrath <bug1@ihug.co.nz>2001-10-25 14:18:08 +0000
commit95ebf618b78814ef250bf40737816784cdaef74d (patch)
tree066dad2c0f8435604210905564c436a4a27ce44c /archival/libunarchive/get_header_ar.c
parent8eaa7b36985e6be193ed0ad1e4cbc493aa8d3cbc (diff)
*** empty log message ***
Diffstat (limited to 'archival/libunarchive/get_header_ar.c')
-rw-r--r--archival/libunarchive/get_header_ar.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/archival/libunarchive/get_header_ar.c b/archival/libunarchive/get_header_ar.c
new file mode 100644
index 000000000..d2840e0e3
--- /dev/null
+++ b/archival/libunarchive/get_header_ar.c
@@ -0,0 +1,106 @@
+/*
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "unarchive.h"
+#include "libbb.h"
+
+file_header_t *get_header_ar(FILE *src_stream)
+{
+ file_header_t *typed;
+ union {
+ char raw[60];
+ struct {
+ char name[16];
+ char date[12];
+ char uid[6];
+ char gid[6];
+ char mode[8];
+ char size[10];
+ char magic[2];
+ } formated;
+ } ar;
+ static char *ar_long_names;
+
+ if (fread(ar.raw, 1, 60, src_stream) != 60) {
+ return(NULL);
+ }
+ archive_offset += 60;
+ /* align the headers based on the header magic */
+ if ((ar.formated.magic[0] != '`') || (ar.formated.magic[1] != '\n')) {
+ /* some version of ar, have an extra '\n' after each data entry,
+ * this puts the next header out by 1 */
+ if (ar.formated.magic[1] != '`') {
+ error_msg("Invalid magic");
+ return(NULL);
+ }
+ /* read the next char out of what would be the data section,
+ * if its a '\n' then it is a valid header offset by 1*/
+ archive_offset++;
+ if (fgetc(src_stream) != '\n') {
+ error_msg("Invalid magic");
+ return(NULL);
+ }
+ /* fix up the header, we started reading 1 byte too early */
+ /* raw_header[60] wont be '\n' as it should, but it doesnt matter */
+ memmove(ar.raw, &ar.raw[1], 59);
+ }
+
+ typed = (file_header_t *) xcalloc(1, sizeof(file_header_t));
+
+ typed->size = (size_t) atoi(ar.formated.size);
+ /* long filenames have '/' as the first character */
+ if (ar.formated.name[0] == '/') {
+ if (ar.formated.name[1] == '/') {
+ /* If the second char is a '/' then this entries data section
+ * stores long filename for multiple entries, they are stored
+ * in static variable long_names for use in future entries */
+ ar_long_names = (char *) xrealloc(ar_long_names, typed->size);
+ fread(ar_long_names, 1, typed->size, src_stream);
+ archive_offset += typed->size;
+ /* This ar entries data section only contained filenames for other records
+ * they are stored in the static ar_long_names for future reference */
+ return (get_header_ar(src_stream)); /* Return next header */
+ } else if (ar.formated.name[1] == ' ') {
+ /* This is the index of symbols in the file for compilers */
+ seek_sub_file(src_stream, typed->size);
+ return (get_header_ar(src_stream)); /* Return next header */
+ } else {
+ /* The number after the '/' indicates the offset in the ar data section
+ (saved in variable long_name) that conatains the real filename */
+ if (!ar_long_names) {
+ error_msg("Cannot resolve long file name");
+ return (NULL);
+ }
+ typed->name = xstrdup(ar_long_names + atoi(&ar.formated.name[1]));
+ }
+ } else {
+ /* short filenames */
+ typed->name = xcalloc(1, 16);
+ strncpy(typed->name, ar.formated.name, 16);
+ }
+ typed->name[strcspn(typed->name, " /")]='\0';
+
+ /* convert the rest of the now valid char header to its typed struct */
+ parse_mode(ar.formated.mode, &typed->mode);
+ typed->mtime = atoi(ar.formated.date);
+ typed->uid = atoi(ar.formated.uid);
+ typed->gid = atoi(ar.formated.gid);
+
+ return(typed);
+} \ No newline at end of file