/* ringbuffer.c
* Routines for packet capture windows
*
- * $Id: ringbuffer.c,v 1.6 2002/09/22 16:17:41 gerald Exp $
+ * $Id: ringbuffer.c,v 1.7 2003/06/22 16:06:03 deniel Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@ethereal.com>
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
+/*
+ * <laurent.deniel@free.fr>
+ *
+ * Almost completely rewritten in order to:
+ *
+ * - be able to use a unlimited number of ringbuffer files
+ * - close the current file and open (truncating) the next file at switch
+ * - set the final file name once open (or reopen)
+ * - avoid the deletion of files that could not be truncated (can't arise now)
+ * and do not erase empty files
+ *
+ * The idea behind that is to remove the limitation of the maximum # of
+ * ringbuffer files being less than the maximum # of open fd per process
+ * and to be able to reduce the amount of virtual memory usage (having only
+ * one file open at most) or the amount of file system usage (by truncating
+ * the files at switch and not the capture stop, and by closing them which
+ * makes possible their move or deletion after a switch).
+ *
+ */
+
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
/* Ringbuffer file structure */
typedef struct _rb_file {
- gchar* name;
- int fd;
- time_t creation_time;
- gboolean is_new;
- guint16 number;
- wtap_dumper* pdh;
- long start_pos;
+ gchar *name;
} rb_file;
/* Ringbuffer data structure */
typedef struct _ringbuf_data {
- rb_file* files;
- guint num_files; /* Number of ringbuffer files */
- guint curr_file_num; /* Number of the current file */
- gchar* fprefix; /* Filename prefix */
- gchar* fsuffix; /* Filename suffix */
+ rb_file *files;
+ guint num_files; /* Number of ringbuffer files */
+ guint curr_file_num; /* Number of the current file */
+ gchar *fprefix; /* Filename prefix */
+ gchar *fsuffix; /* Filename suffix */
+ gboolean unlimited; /* TRUE if unlimited number of files */
+ int filetype;
+ int linktype;
+ int snaplen;
+ guint16 number;
+ int fd; /* Current ringbuffer file descriptor */
+ wtap_dumper *pdh;
} ringbuf_data;
-/* Create the ringbuffer data structure */
static ringbuf_data rb_data;
+static int ringbuf_open_file(rb_file *rfile, int *err)
+{
+ char filenum[5+1];
+ char timestr[14+1];
+ time_t current_time;
+
+ if (rfile->name != NULL) {
+ if (rb_data.unlimited == FALSE) {
+ /* remove old file (if any, so ignore error) */
+ unlink(rfile->name);
+ }
+ g_free(rfile->name);
+ }
+
+#ifdef _WIN32
+ _tzset();
+#endif
+ current_time = time(NULL);
+
+ rb_data.number++;
+
+ snprintf(filenum, sizeof(filenum), "%05d", rb_data.number);
+ strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(¤t_time));
+ rfile->name = g_strconcat(rb_data.fprefix, "_", filenum, "_", timestr,
+ rb_data.fsuffix, NULL);
+
+ if (rfile->name == NULL) {
+ *err = ENOMEM;
+ return -1;
+ }
+
+ rb_data.fd = open(rfile->name, O_RDWR|O_BINARY|O_TRUNC|O_CREAT, 0600);
+
+ if (rb_data.fd == -1 && err != NULL) {
+ *err = errno;
+ }
+
+ return rb_data.fd;
+}
+
/*
- * Initialize the ringbuffer data structure
+ * Initialize the ringbuffer data structures
*/
int
ringbuf_init(const char *capfile_name, guint num_files)
{
- int save_file_fd;
unsigned int i;
char *pfx;
gchar *save_file;
- char save_file_num[3+1];
+
+ rb_data.files = NULL;
+ rb_data.curr_file_num = 0;
+ rb_data.fprefix = NULL;
+ rb_data.fsuffix = NULL;
+ rb_data.unlimited = FALSE;
+ rb_data.fd = -1;
+ rb_data.pdh = NULL;
+ rb_data.number = 0;
/* just to be sure ... */
if (num_files <= RINGBUFFER_MAX_NUM_FILES) {
return -1;
}
- /* Open the initial file */
- save_file_fd = open(capfile_name, O_RDWR|O_BINARY|O_TRUNC|O_CREAT, 0600);
- if (save_file_fd == -1) {
- /* open failed */
- return -1;
- }
-
- /* allocate memory */
- rb_data.files = (rb_file *)calloc(num_files, sizeof(rb_file));
- if (rb_data.files == NULL) {
- /* could not allocate memory */
- return -1;
- }
-
- /* initialize */
- rb_data.fprefix = NULL;
- rb_data.fsuffix = NULL;
- for (i=0; i<rb_data.num_files; i++) {
- rb_data.files[i].name = NULL;
- rb_data.files[i].fd = -1;
- }
+ /* set file name prefix/suffix */
- /* get file name prefix/suffix */
save_file = g_strdup(capfile_name);
pfx = strrchr(save_file,'.');
if (pfx != NULL) {
g_free(save_file);
save_file = NULL;
-#ifdef _WIN32
- _tzset();
-#endif
- /* save the initial file parameters */
- rb_data.files[0].name = g_strdup(capfile_name);
- rb_data.files[0].fd = save_file_fd;
- rb_data.files[0].creation_time = time(NULL);
- rb_data.files[0].number = 0;
- rb_data.files[0].is_new = TRUE;
-
- /* create the other files */
- for (i=1; i<rb_data.num_files; i++) {
- /* create a file name */
- snprintf(save_file_num,3+1,"%03d",i);
- save_file = g_strconcat(capfile_name, ".", save_file_num, NULL);
- /* open the file */
- save_file_fd = open(save_file, O_RDWR|O_BINARY|O_TRUNC|O_CREAT, 0600);
- if (save_file_fd != -1) {
- rb_data.files[i].name = save_file;
- rb_data.files[i].fd = save_file_fd;
- rb_data.files[i].creation_time = time(NULL);
- rb_data.files[i].number = i;
- rb_data.files[i].is_new = TRUE;
- } else {
- /* could not open a file */
- ringbuf_error_cleanup();
- return -1;
- }
+ /* allocate rb_file structures (only one if unlimited since there is no
+ need to save all file names in that case) */
+
+ if (num_files == RINGBUFFER_UNLIMITED_FILES) {
+ rb_data.unlimited = TRUE;
+ rb_data.num_files = 1;
}
- /* done */
- rb_data.curr_file_num = 0;
- return rb_data.files[0].fd;
+ rb_data.files = g_malloc(rb_data.num_files * sizeof(rb_file));
+ if (rb_data.files == NULL) {
+ return -1;
+ }
+
+ for (i=0; i < rb_data.num_files; i++) {
+ rb_data.files[i].name = NULL;
+ }
+
+ /* create the first file */
+ if (ringbuf_open_file(&rb_data.files[0], NULL) == -1) {
+ ringbuf_error_cleanup();
+ return -1;
+ }
+
+ return rb_data.fd;
}
/*
- * Calls wtap_dump_fdopen() for all ringbuffer files
+ * Calls wtap_dump_fdopen() for the current ringbuffer file
*/
wtap_dumper*
-ringbuf_init_wtap_dump_fdopen(int filetype, int linktype,
- int snaplen, int *err)
+ringbuf_init_wtap_dump_fdopen(int filetype, int linktype, int snaplen, int *err)
{
- unsigned int i;
- FILE *fh;
-
- for (i=0; i<rb_data.num_files; i++) {
- rb_data.files[i].pdh = wtap_dump_fdopen(rb_data.files[i].fd, filetype,
- linktype, snaplen, err);
- if (rb_data.files[i].pdh == NULL) {
- /* could not open file */
- return NULL;
- } else {
- /*
- * Flush out the capture file header, as written by "wtap_dump_fdopen()".
- *
- * XXX - this relies on Wiretap writing out data sequentially,
- * and writing the entire capture file header when the file
- * is created. That happens to be true for libpcap files,
- * which are Ethereal's native capture files, and which are
- * therefore the capture file types we're writing, but is not
- * true for all the capture file types Wiretap can write.
- */
- fh = wtap_dump_file(rb_data.files[i].pdh);
- if (fflush(fh) == EOF) {
- if (err != NULL) {
- *err = errno;
- }
- return NULL;
- }
- if ((rb_data.files[i].start_pos = ftell(fh)) < 0) {
- if (err != NULL) {
- *err = errno;
- }
- return NULL;
- }
- clearerr(fh);
- }
- }
- /* done */
- rb_data.files[0].is_new = FALSE;
- return rb_data.files[0].pdh;
+
+ rb_data.filetype = filetype;
+ rb_data.linktype = linktype;
+ rb_data.snaplen = snaplen;
+
+ rb_data.pdh = wtap_dump_fdopen(rb_data.fd, filetype, linktype, snaplen, err);
+
+ return rb_data.pdh;
}
/*
gboolean
ringbuf_switch_file(capture_file *cf, wtap_dumper **pdh, int *err)
{
- int next_file_num;
- FILE *fh;
- gboolean err_on_next = FALSE;
-
- /* flush the current file */
- fh = wtap_dump_file(rb_data.files[rb_data.curr_file_num].pdh);
- clearerr(fh);
- errno = WTAP_ERR_CANT_CLOSE;
- if (fflush(fh) == EOF) {
- if (err != NULL) {
- *err = errno;
- }
+ int next_file_num;
+ rb_file *next_rfile = NULL;
+
+ /* close current file */
+
+ if (!wtap_dump_close(rb_data.pdh, err)) {
+ close(rb_data.fd);
+ rb_data.fd = -1;
return FALSE;
}
- /* get the next file number */
- next_file_num = (rb_data.curr_file_num + 1) % rb_data.num_files;
- /* prepare the file if it was already used */
- if (!rb_data.files[next_file_num].is_new) {
- /* rewind to the position after the file header */
- fh = wtap_dump_file(rb_data.files[next_file_num].pdh);
- if (fseek(fh, rb_data.files[next_file_num].start_pos, SEEK_SET) < 0) {
- *err = errno;
- /* Don't return straight away: have caller report correct save_file */
- err_on_next = TRUE;
- }
- wtap_set_bytes_dumped(rb_data.files[next_file_num].pdh,
- rb_data.files[next_file_num].start_pos);
- /* set the absolute file number */
- rb_data.files[next_file_num].number += rb_data.num_files;
+ rb_data.pdh = NULL;
+ rb_data.fd = -1;
+
+ /* get the next file number and open it */
+
+ next_file_num = (rb_data.curr_file_num + 1) % rb_data.num_files;
+ next_rfile = &rb_data.files[next_file_num];
+
+ if (ringbuf_open_file(next_rfile, err) == -1) {
+ return FALSE;
}
-#ifdef _WIN32
- _tzset();
-#endif
- rb_data.files[next_file_num].creation_time = time(NULL);
- /* switch to the new file */
- cf->save_file = rb_data.files[next_file_num].name;
- cf->save_file_fd = rb_data.files[next_file_num].fd;
- (*pdh) = rb_data.files[next_file_num].pdh;
- /* mark the file as used */
- rb_data.files[next_file_num].is_new = FALSE;
- /* finally set the current file number */
- rb_data.curr_file_num = next_file_num;
- if (err_on_next)
+ if (ringbuf_init_wtap_dump_fdopen(rb_data.filetype, rb_data.linktype,
+ rb_data.snaplen, err) == NULL) {
return FALSE;
+ }
+
+ /* switch to the new file */
+ rb_data.curr_file_num = next_file_num;
+ cf->save_file = next_rfile->name;
+ cf->save_file_fd = rb_data.fd;
+ (*pdh) = rb_data.pdh;
return TRUE;
}
/*
- * Calls wtap_dump_close() for all ringbuffer files
+ * Calls wtap_dump_close() for the current ringbuffer file
*/
gboolean
ringbuf_wtap_dump_close(capture_file *cf, int *err)
{
- gboolean ret_val;
- gboolean data_captured = TRUE;
- unsigned int i;
- long curr_pos;
- long curr_file_curr_pos = 0; /* Initialise to avoid GCC warning */
- gchar *new_name;
- char filenum[5+1];
- char timestr[14+1];
- FILE *fh;
-
- /* assume success */
- ret_val = TRUE;
- /* close all files */
- for (i=0; i<rb_data.num_files; i++) {
- fh = wtap_dump_file(rb_data.files[i].pdh);
- clearerr(fh);
-
- /* Get the current file position */
- if ((curr_pos = ftell(fh)) < 0) {
- if (err != NULL) {
- *err = errno;
- }
- ret_val = FALSE;
- /* If the file's not a new one, remove it as it hasn't been truncated
- and thus contains garbage at the end.
- If the file is a new one, it contains only the dump header, so
- remove it too. */
- close(rb_data.files[i].fd);
- unlink(rb_data.files[i].name);
- /* Set name for caller's error message */
- cf->save_file = rb_data.files[i].name;
- continue;
- }
-
- if (i == rb_data.curr_file_num)
- curr_file_curr_pos = curr_pos;
-
- /* If buffer 0 is empty and the ring hasn't wrapped,
- no data has been captured. */
- if (i == 0 && curr_pos == rb_data.files[0].start_pos &&
- rb_data.files[0].number == 0)
- data_captured = FALSE;
-
- /* Flush the file */
- errno = WTAP_ERR_CANT_CLOSE;
- if (fflush(fh) == EOF) {
- if (err != NULL) {
- *err = errno;
- }
- ret_val = FALSE;
- close(rb_data.files[i].fd);
- unlink(rb_data.files[i].name);
- cf->save_file = rb_data.files[i].name;
- continue;
- }
+ gboolean ret_val = TRUE;
- /* Truncate the file to the current size. This must be done in order
- to get rid of the 'garbage' packets at the end of the file from
- previous usage */
- if (!rb_data.files[i].is_new) {
- if (ftruncate(rb_data.files[i].fd, curr_pos) != 0) {
- /* could not truncate the file */
- if (err != NULL) {
- *err = errno;
- }
- ret_val = FALSE;
- /* remove the file since it contains garbage at the end */
- close(rb_data.files[i].fd);
- unlink(rb_data.files[i].name);
- cf->save_file = rb_data.files[i].name;
- continue;
- }
- }
- /* close the file */
- if (!wtap_dump_close(rb_data.files[i].pdh, err)) {
- /* error only if it is a used file */
- if (curr_pos > rb_data.files[i].start_pos) {
- ret_val = FALSE;
- /* Don't unlink it; maybe the user can salvage it. */
- cf->save_file = rb_data.files[i].name;
- continue;
- }
- }
+ /* close current file */
- /* Rename buffers which have data and delete empty buffers --
- except if no data at all has been captured we need to keep
- the empty first buffer. */
- if (curr_pos > rb_data.files[i].start_pos ||
- (i == 0 && !data_captured)) {
- /* rename the file */
- snprintf(filenum,5+1,"%05d",rb_data.files[i].number);
- strftime(timestr,14+1,"%Y%m%d%H%M%S",
- localtime(&(rb_data.files[i].creation_time)));
- new_name = g_strconcat(rb_data.fprefix,"_", filenum, "_", timestr,
- rb_data.fsuffix, NULL);
- if (rename(rb_data.files[i].name, new_name) != 0) {
- /* save the latest error */
- if (err != NULL) {
- *err = errno;
- }
- ret_val = FALSE;
- cf->save_file = rb_data.files[i].name;
- g_free(new_name);
- } else {
- g_free(rb_data.files[i].name);
- rb_data.files[i].name = new_name;
- }
- } else {
- /* this file is empty - remove it */
- unlink(rb_data.files[i].name);
- }
+ if (!wtap_dump_close(rb_data.pdh, err)) {
+ close(rb_data.fd);
+ ret_val = FALSE;
}
- if (ret_val) {
- /* Make the current file the save file, or if it's empty apart from
- the header, make the previous file the save file (assuming data
- has been captured). */
- if (curr_file_curr_pos ==
- rb_data.files[rb_data.curr_file_num].start_pos &&
- data_captured) {
- if (rb_data.curr_file_num > 0)
- rb_data.curr_file_num -= 1;
- else
- rb_data.curr_file_num = rb_data.num_files - 1;
- }
- cf->save_file = rb_data.files[rb_data.curr_file_num].name;
- }
+ rb_data.pdh = NULL;
+ rb_data.fd = -1;
+
+ cf->save_file = rb_data.files[rb_data.curr_file_num].name;
return ret_val;
}
if (rb_data.files != NULL) {
for (i=0; i < rb_data.num_files; i++) {
- g_free(rb_data.files[i].name);
- rb_data.files[i].name = NULL;
+ if (rb_data.files[i].name != NULL) {
+ g_free(rb_data.files[i].name);
+ rb_data.files[i].name = NULL;
+ }
}
- free(rb_data.files);
+ g_free(rb_data.files);
rb_data.files = NULL;
}
- g_free(rb_data.fprefix);
- g_free(rb_data.fsuffix);
+ if (rb_data.fprefix != NULL) {
+ g_free(rb_data.fprefix);
+ rb_data.fprefix = NULL;
+ }
+ if (rb_data.fsuffix != NULL) {
+ g_free(rb_data.fsuffix);
+ rb_data.fsuffix = NULL;
+ }
}
/*
{
unsigned int i;
- if (rb_data.files == NULL) {
- ringbuf_free();
- return;
+ /* try to close via wtap */
+ if (rb_data.pdh != NULL) {
+ if (wtap_dump_close(rb_data.pdh, NULL)) {
+ rb_data.fd = -1;
+ }
+ rb_data.pdh = NULL;
}
- for (i=0; i<rb_data.num_files; i++) {
- /* try to close via wtap */
- if (rb_data.files[i].pdh != NULL) {
- if (wtap_dump_close(rb_data.files[i].pdh, NULL)) {
- /* done */
- rb_data.files[i].fd = -1;
- }
- }
- /* close directly if still open */
- if (rb_data.files[i].fd != -1) {
- close(rb_data.files[i].fd);
- }
- /* remove the other files, the initial file will be handled
- by the calling funtion */
+ /* close directly if still open */
+ if (rb_data.fd != -1) {
+ close(rb_data.fd);
+ rb_data.fd = -1;
+ }
+
+ for (i=0; i < rb_data.num_files; i++) {
if (rb_data.files[i].name != NULL) {
unlink(rb_data.files[i].name);
}
git.samba.org / obnox / wireshark / wip.git / commitdiff