diff options
Diffstat (limited to 'cfile.c')
| -rw-r--r-- | cfile.c | 96 |
1 files changed, 83 insertions, 13 deletions
@@ -37,19 +37,21 @@ void cap_file_init(capture_file *cf) { /* Initialize the capture file struct */ - cf->plist_start = NULL; - cf->plist_end = NULL; - cf->wth = NULL; - cf->filename = NULL; - cf->source = NULL; - cf->user_saved = FALSE; - cf->is_tempfile = FALSE; - cf->rfcode = NULL; - cf->dfilter = NULL; - cf->has_snap = FALSE; - cf->snap = WTAP_MAX_PACKET_SIZE; - cf->count = 0; - cf->redissecting = FALSE; + cf->plist_start = NULL; + cf->plist_end = NULL; + cf->wth = NULL; + cf->filename = NULL; + cf->source = NULL; + cf->user_saved = FALSE; + cf->is_tempfile = FALSE; + cf->rfcode = NULL; + cf->dfilter = NULL; + cf->has_snap = FALSE; + cf->snap = WTAP_MAX_PACKET_SIZE; + cf->count = 0; + cf->last_found_num = 0; + cf->last_found_fd = NULL; + cf->redissecting = FALSE; } void @@ -64,3 +66,71 @@ cap_file_add_fdata(capture_file *cf, frame_data *fdata) cf->plist_end = fdata; } +/* + * Find the frame_data for the specified frame number. + * Do some caching to make this work reasonably fast for + * forward and backward sequential passes through the packets. + */ +frame_data * +cap_file_find_fdata(capture_file *cf, guint32 num) +{ + frame_data *fdata; + + if (num == 0) { + /* There is no frame number 0 */ + return NULL; + } + + /* + * Did we remember a frame number from a sequential pass through + * the frames? + */ + if (cf->last_found_num != 0) { + /* + * Yes. Is this that frame? + */ + if (num == cf->last_found_num) { + /* Yes - return it. */ + return cf->last_found_fd; + } + + /* + * No. Is it the frame just after that frame? + */ + if (num == cf->last_found_num + 1) { + /* + * Yes - if there is such a frame, remember it and return it. + */ + fdata = cf->last_found_fd->next; + if (fdata != NULL) { + cf->last_found_num = num; + cf->last_found_fd = fdata; + } + return fdata; /* could be null, if there is no such frame */ + } + + /* + * No. Is it the frame just before that frame? + */ + if (num == cf->last_found_num - 1) { + /* + * Yes - if there is such a frame, remember it and return it. + */ + fdata = cf->last_found_fd->prev; + if (fdata != NULL) { + cf->last_found_num = num; + cf->last_found_fd = fdata; + } + return fdata; /* could be null, if there is no such frame */ + } + } + + for (fdata = cf->plist_start; fdata != NULL && fdata->num < num; + fdata = fdata->next) + ; + if (fdata != NULL) { + cf->last_found_num = num; + cf->last_found_fd = fdata; + } + return fdata; +} |