diff options
author | Guy Harris <guy@alum.mit.edu> | 2012-05-04 16:56:18 +0000 |
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committer | Guy Harris <guy@alum.mit.edu> | 2012-05-04 16:56:18 +0000 |
commit | 33bb54a9452f4be53377a185195a63194016241a (patch) | |
tree | 9308829e2105b6e51e0dc5cc0af2295d8d97a0a3 /wiretap/btsnoop.c | |
parent | f65cb5f27bab6310e847f88cd763eb08bff1c93b (diff) |
file_seek() used to be a wrapper around fseek() or gzseek(), both of
which could use lseek() and were thus expensive due to system call
overhead. To avoid making a system call for every packet on a
sequential read, we maintained a data_offset field in the wtap structure
for sequential reads.
It's now a routine that just returns information from the FILE_T data
structure, so it's cheap. Use it, rather than maintaining the data_offset
field.
Readers for some file formats need to maintain file offset themselves;
have them do so in their private data structures.
svn path=/trunk/; revision=42423
Diffstat (limited to 'wiretap/btsnoop.c')
-rw-r--r-- | wiretap/btsnoop.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/wiretap/btsnoop.c b/wiretap/btsnoop.c index a8e6d80e73..c9397d556b 100644 --- a/wiretap/btsnoop.c +++ b/wiretap/btsnoop.c @@ -98,7 +98,6 @@ int btsnoop_open(wtap *wth, int *err, gchar **err_info) return -1; return 0; } - wth->data_offset += sizeof magic; if (memcmp(magic, btsnoop_magic, sizeof btsnoop_magic) != 0) { return 0; @@ -113,7 +112,6 @@ int btsnoop_open(wtap *wth, int *err, gchar **err_info) return -1; return 0; } - wth->data_offset += sizeof hdr; /* * Make sure it's a version we support. @@ -169,7 +167,7 @@ static gboolean btsnoop_read(wtap *wth, int *err, gchar **err_info, /* As the send/receive flag is stored in the middle of the capture header but needs to go in the pseudo header for wiretap, the header needs to be reread in the seek_read function*/ - *data_offset = wth->data_offset; + *data_offset = file_tell(wth->fh); /* Read record header. */ errno = WTAP_ERR_CANT_READ; @@ -180,7 +178,6 @@ static gboolean btsnoop_read(wtap *wth, int *err, gchar **err_info, *err = WTAP_ERR_SHORT_READ; return FALSE; } - wth->data_offset += sizeof hdr; packet_size = g_ntohl(hdr.incl_len); orig_size = g_ntohl(hdr.orig_len); @@ -201,7 +198,6 @@ static gboolean btsnoop_read(wtap *wth, int *err, gchar **err_info, packet_size, err, err_info)) { return FALSE; /* Read error */ } - wth->data_offset += packet_size; ts = GINT64_FROM_BE(hdr.ts_usec); ts -= KUnixTimeBase; |