diff options
| author | Guy Harris <guy@alum.mit.edu> | 2012-05-04 16:56:18 +0000 |
|---|---|---|
| committer | Guy Harris <guy@alum.mit.edu> | 2012-05-04 16:56:18 +0000 |
| commit | 33bb54a9452f4be53377a185195a63194016241a (patch) | |
| tree | 9308829e2105b6e51e0dc5cc0af2295d8d97a0a3 /wiretap/iptrace.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/iptrace.c')
| -rw-r--r-- | wiretap/iptrace.c | 11 |
1 files changed, 2 insertions, 9 deletions
diff --git a/wiretap/iptrace.c b/wiretap/iptrace.c index 3b6c7739e2..1dca53675d 100644 --- a/wiretap/iptrace.c +++ b/wiretap/iptrace.c @@ -65,7 +65,6 @@ int iptrace_open(wtap *wth, int *err, gchar **err_info) return -1; return 0; } - wth->data_offset += 11; name[11] = 0; if (strcmp(name, "iptrace 1.0") == 0) { @@ -134,14 +133,13 @@ static gboolean iptrace_read_1_0(wtap *wth, int *err, gchar **err_info, guint8 fddi_padding[3]; /* Read the descriptor data */ - *data_offset = wth->data_offset; + *data_offset = file_tell(wth->fh); ret = iptrace_read_rec_header(wth->fh, header, IPTRACE_1_0_PHDR_SIZE, err, err_info); if (ret <= 0) { /* Read error or EOF */ return FALSE; } - wth->data_offset += IPTRACE_1_0_PHDR_SIZE; /* * Byte 28 of the frame header appears to be a BSD-style IFT_xxx @@ -185,7 +183,6 @@ static gboolean iptrace_read_1_0(wtap *wth, int *err, gchar **err_info, return FALSE; } packet_size -= 3; - wth->data_offset += 3; /* * Read the padding. @@ -210,7 +207,6 @@ static gboolean iptrace_read_1_0(wtap *wth, int *err, gchar **err_info, if (!iptrace_read_rec_data(wth->fh, data_ptr, packet_size, err, err_info)) return FALSE; /* Read error */ - wth->data_offset += packet_size; wth->phdr.presence_flags = WTAP_HAS_TS; wth->phdr.len = packet_size; @@ -349,14 +345,13 @@ static gboolean iptrace_read_2_0(wtap *wth, int *err, gchar **err_info, guint8 fddi_padding[3]; /* Read the descriptor data */ - *data_offset = wth->data_offset; + *data_offset = file_tell(wth->fh); ret = iptrace_read_rec_header(wth->fh, header, IPTRACE_2_0_PHDR_SIZE, err, err_info); if (ret <= 0) { /* Read error or EOF */ return FALSE; } - wth->data_offset += IPTRACE_2_0_PHDR_SIZE; /* * Byte 28 of the frame header appears to be a BSD-style IFT_xxx @@ -400,7 +395,6 @@ static gboolean iptrace_read_2_0(wtap *wth, int *err, gchar **err_info, return FALSE; } packet_size -= 3; - wth->data_offset += 3; /* * Read the padding. @@ -425,7 +419,6 @@ static gboolean iptrace_read_2_0(wtap *wth, int *err, gchar **err_info, if (!iptrace_read_rec_data(wth->fh, data_ptr, packet_size, err, err_info)) return FALSE; /* Read error */ - wth->data_offset += packet_size; wth->phdr.presence_flags = WTAP_HAS_TS; wth->phdr.len = packet_size; |