rpm2cpio applet by Laurence Anderson
diff --git a/rpm2cpio.c b/rpm2cpio.c
new file mode 100644
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--- /dev/null
+++ b/rpm2cpio.c
@@ -0,0 +1,92 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini rpm2cpio implementation for busybox
+ *
+ * Copyright (C) 2001 by Laurence Anderson
+ *
+ * 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
+ * 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 "busybox.h"
+#include <netinet/in.h> /* For ntohl & htonl function */
+#include <string.h>
+
+#define RPM_MAGIC "\355\253\356\333"
+#define RPM_HEADER_MAGIC "\216\255\350"
+
+typedef unsigned char u8;
+typedef unsigned short u16;
+typedef unsigned int u32;
+
+struct rpm_lead {
+ unsigned char magic[4];
+ u8 major, minor;
+ u16 type;
+ u16 archnum;
+ char name[66];
+ u16 osnum;
+ u16 signature_type;
+ char reserved[16];
+};
+
+struct rpm_header {
+ char magic[3]; /* 3 byte magic: 0x8e 0xad 0xe8 */
+ u8 version; /* 1 byte version number */
+ u32 reserved; /* 4 bytes reserved */
+ u32 entries; /* Number of entries in header (4 bytes) */
+ u32 size; /* Size of store (4 bytes) */
+};
+
+void skip_header(FILE *rpmfile)
+{
+ struct rpm_header header;
+
+ fread(&header, sizeof(struct rpm_header), 1, rpmfile);
+ if (strncmp((char *) &header.magic, RPM_HEADER_MAGIC, 3) != 0) error_msg_and_die("Invalid RPM header magic"); /* Invalid magic */
+ if (header.version != 1) error_msg_and_die("Unsupported RPM header version"); /* This program only supports v1 headers */
+ header.entries = ntohl(header.entries);
+ header.size = ntohl(header.size);
+ fseek (rpmfile, 16 * header.entries, SEEK_CUR); /* Seek past index entries */
+ fseek (rpmfile, header.size, SEEK_CUR); /* Seek past store */
+}
+
+/* No getopt required */
+extern int rpm2cpio_main(int argc, char **argv)
+{
+ struct rpm_lead lead;
+ int gunzip_pid;
+ FILE *rpmfile, *cpiofile;
+
+ if (argc == 1) {
+ rpmfile = stdin;
+ } else {
+ rpmfile = fopen(argv[1], "r");
+ if (!rpmfile) perror_msg_and_die("Can't open rpm file");
+ }
+
+ fread (&lead, sizeof(struct rpm_lead), 1, rpmfile);
+ if (strncmp((char *) &lead.magic, RPM_MAGIC, 4) != 0) error_msg_and_die("Invalid RPM magic"); /* Just check the magic, the rest is irrelevant */
+ /* Skip the signature header */
+ skip_header(rpmfile);
+ fseek(rpmfile, (8 - (ftell(rpmfile) % 8)) % 8, SEEK_CUR); /* Pad to 8 byte boundary */
+ /* Skip the main header */
+ skip_header(rpmfile);
+
+ cpiofile = gz_open(rpmfile, &gunzip_pid);
+ copyfd(fileno(cpiofile), fileno(stdout));
+ gz_close(gunzip_pid);
+ fclose(rpmfile);
+ return 0;
+}