initial support for reading archive files (*.a)

1 files changed, 78 insertions, 1 deletions

diff --git a/paxinc.c b/paxinc.c
index 86ce56a..707468e 100644
--- a/paxinc.c
+++ b/paxinc.c
@@ -1,7 +1,7 @@
 /*
  * Copyright 2003-2006 Gentoo Foundation
  * Distributed under the terms of the GNU General Public License v2
- * $Header: /var/cvsroot/gentoo-projects/pax-utils/paxinc.c,v 1.2 2006/01/05 03:12:07 vapier Exp $
+ * $Header: /var/cvsroot/gentoo-projects/pax-utils/paxinc.c,v 1.3 2006/01/13 12:12:52 vapier Exp $
  *
  * Copyright 2005-2006 Ned Ludd        - <solar@gentoo.org>
  * Copyright 2005-2006 Mike Frysinger  - <vapier@gentoo.org>
@@ -9,8 +9,85 @@
 
 /* stick common symbols here that are needed by paxinc.h */
 
+#define IN_paxinc
 #include "paxinc.h"
 
 #define argv0 "paxinc"
 
 char do_reverse_endian;
+
+/* some of this ar code was taken from busybox */
+
+#define AR_MAGIC "!<arch>"
+#define AR_MAGIC_SIZE (sizeof(AR_MAGIC)-1) /* dont count null byte */
+archive_handle *ar_open(const char *filename)
+{
+	static archive_handle ret;
+	char buf[AR_MAGIC_SIZE];
+
+	if ((ret.fd=open(filename, O_RDONLY)) == -1)
+		err("Could not open '%s'", filename);
+
+	memset(buf, 0x00, sizeof(buf));
+	if (read(ret.fd, buf, AR_MAGIC_SIZE) != AR_MAGIC_SIZE) {
+close_and_ret:
+		close(ret.fd);
+		return NULL;
+	}
+	if (strncmp(buf, AR_MAGIC, AR_MAGIC_SIZE))
+		goto close_and_ret;
+
+	ret.filename = filename;
+
+	return &ret;
+}
+
+archive_member *ar_next(archive_handle *ar)
+{
+	char *s;
+	size_t len;
+	static archive_member ret;
+
+	if (read(ar->fd, ret.buf.raw, sizeof(ret.buf.raw)) != sizeof(ret.buf.raw)) {
+close_and_ret:
+		close(ar->fd);
+		return NULL;
+	}
+
+	/* ar header starts on an even byte (2 byte aligned)
+	 * '\n' is used for padding */
+	if (ret.buf.raw[0] == '\n') {
+		memmove(ret.buf.raw, ret.buf.raw+1, 59);
+		read(ar->fd, ret.buf.raw+59, 1);
+	}
+
+	if ((ret.buf.formated.magic[0] != '`') || (ret.buf.formated.magic[1] != '\n')) {
+		warn("Invalid ar entry");
+		goto close_and_ret;
+	}
+
+	if (ret.buf.formated.name[0] == '/') {
+		warn("Sorry, long filenames not supported at this time");
+		goto close_and_ret;
+	}
+
+	len = strlen(ar->filename);
+	assert(len < sizeof(ret.name)-sizeof(ret.buf.formated.name)-1);
+	memcpy(ret.name, ar->filename, len);
+	ret.name[len++] = ':';
+	memcpy(ret.name+len, ret.buf.formated.name, sizeof(ret.buf.formated.name));
+	if ((s=strchr(ret.name+len, '/')) != NULL)
+		*s = '\0';
+	else
+		ret.name[len+sizeof(ret.name)-1] = '\0';
+	ret.date = atoi(ret.buf.formated.date);
+	ret.uid = atoi(ret.buf.formated.uid);
+	ret.gid = atoi(ret.buf.formated.gid);
+	ret.mode = strtol(ret.buf.formated.mode, NULL, 8);
+	ret.size = atoi(ret.buf.formated.size);
+
+	if (lseek(ar->fd, ret.size, SEEK_CUR) == -1)
+		goto close_and_ret;
+
+	return &ret;
+}