From 0a130d510dc5272dc2fc7bc5a116f0694c8bd2a9 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 28 Aug 2009 21:09:51 +0200 Subject: rpm2cpio: handle unseekable input correctly function old new delta data_skip 14 20 +6 seek_by_jump 67 72 +5 data_align 81 84 +3 seek_by_read 20 19 -1 skip_header 99 94 -5 rpm2cpio_main 183 177 -6 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 3/3 up/down: 14/-12) Total: 2 bytes Signed-off-by: Denys Vlasenko --- archival/rpm2cpio.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'archival/rpm2cpio.c') diff --git a/archival/rpm2cpio.c b/archival/rpm2cpio.c index 566a9f213..30ec80e22 100644 --- a/archival/rpm2cpio.c +++ b/archival/rpm2cpio.c @@ -33,9 +33,10 @@ struct rpm_header { uint32_t size; /* Size of store (4 bytes) */ }; -static off_t skip_header(int rpm_fd) +static unsigned skip_header(int rpm_fd) { struct rpm_header header; + unsigned len; xread(rpm_fd, &header, sizeof(header)); // if (strncmp((char *) &header.magic, RPM_HEADER_MAGIC_STR, 3) != 0) { @@ -48,10 +49,12 @@ static off_t skip_header(int rpm_fd) bb_error_msg_and_die("invalid RPM header magic or unsupported version"); // ": %x != %x", header.magic_and_ver, htonl(RPM_HEADER_VERnMAGIC)); } - /* Seek past index entries */ - lseek(rpm_fd, 16 * ntohl(header.entries), SEEK_CUR); - /* Seek past store */ - return lseek(rpm_fd, ntohl(header.size), SEEK_CUR); + + /* Seek past index entries, and past store */ + len = 16 * ntohl(header.entries) + ntohl(header.size); + seek_by_jump(rpm_fd, len); + + return sizeof(header) + len; } /* No getopt required */ @@ -60,7 +63,7 @@ int rpm2cpio_main(int argc UNUSED_PARAM, char **argv) { struct rpm_lead lead; int rpm_fd; - off_t pos; + unsigned pos; unsigned char magic[2]; IF_DESKTOP(long long) int FAST_FUNC (*unpack)(int src_fd, int dst_fd); @@ -78,7 +81,7 @@ int rpm2cpio_main(int argc UNUSED_PARAM, char **argv) /* Skip the signature header, align to 8 bytes */ pos = skip_header(rpm_fd); - lseek(rpm_fd, (8 - (unsigned)pos) & 7, SEEK_CUR); + seek_by_jump(rpm_fd, (8 - pos) & 7); /* Skip the main header */ skip_header(rpm_fd); -- cgit v1.2.3