Hoist a bunch of common code between ascend_read() and

ascend_seek_read() into parse_ascend().

Adjust the buffer size *before* attempting to fill it up.

svn path=/trunk/; revision=49343

3 files changed, 70 insertions, 91 deletions

diff --git a/wiretap/ascend-int.h b/wiretap/ascend-int.h
index faa7f03259..e53b472865 100644
--- a/wiretap/ascend-int.h
+++ b/wiretap/ascend-int.h
@@ -33,14 +33,6 @@
 #include <glib.h>
 #include "ws_symbol_export.h"
 
-typedef struct {
-  time_t start_time;
-  time_t secs;
-  int usecs;
-  guint32 caplen;
-  guint32 len;
-} ascend_pkthdr;
-
 extern int at_eof;
 
 extern const gchar *ascend_parse_error;
@@ -50,6 +42,12 @@ extern const gchar *ascend_parse_error;
  */
 extern struct ascend_phdr *pseudo_header;
 
+typedef struct {
+	time_t inittime;
+	gboolean adjusted;
+	gint64 next_packet_seek_start;
+} ascend_t;
+
 /* Here we provide interfaces to make our scanner act and look like lex */
 int ascendlex(void);
 
@@ -60,7 +58,7 @@ typedef enum {
     PARSED_NONRECORD,
     PARSE_FAILED
 } parse_t;
-parse_t parse_ascend(FILE_T fh, guint8 *pd, struct ascend_phdr *phdr,
-		ascend_pkthdr *hdr, gint64 *start_of_data);
+parse_t parse_ascend(ascend_t *ascend, FILE_T fh, struct wtap_pkthdr *phdr,
+		guint8 *pd);
 
 #endif /* ! __ASCEND_INT_H__ */
diff --git a/wiretap/ascend.y b/wiretap/ascend.y
index 6e1f36f8e3..3f6ea62da9 100644
--- a/wiretap/ascend.y
+++ b/wiretap/ascend.y
@@ -446,14 +446,14 @@ init_parse_ascend(void)
      PARSED_NONRECORD if the parser succeeded but didn't see a packet
      PARSE_FAILED if the parser failed. */
 parse_t
-parse_ascend(FILE_T fh, guint8 *pd, struct ascend_phdr *phdr,
-		ascend_pkthdr *header, gint64 *start_of_data)
+parse_ascend(ascend_t *ascend, FILE_T fh, struct wtap_pkthdr *phdr, guint8 *pd)
 {
   /* yydebug = 1; */
   int retval;
+
   ascend_init_lexer(fh);
   pkt_data = pd;
-  pseudo_header = phdr;
+  pseudo_header = &phdr->pseudo_header.ascend;
 
   bcur = 0;
   first_hexbyte = 0;
@@ -482,14 +482,16 @@ parse_ascend(FILE_T fh, guint8 *pd, struct ascend_phdr *phdr,
      maybe this record was broken. Advance so we don't get into
      an infinite loop reading a broken trace. */
   if (first_hexbyte) {
-    *start_of_data = first_hexbyte;
+    if (ascend != NULL)
+      ascend->next_packet_seek_start = first_hexbyte;
   } else {
     /* Sometimes, a header will be printed but the data will be omitted, or
        worse -- two headers will be printed, followed by the data for each.
        Because of this, we need to be fairly tolerant of what we accept
        here.  If we didn't find any hex bytes, skip over what we've read so
        far so we can try reading a new packet. */
-    *start_of_data = file_tell(fh);
+    if (ascend != NULL)
+      ascend->next_packet_seek_start = file_tell(fh);
     retval = 0;
   }
 
@@ -498,12 +500,52 @@ parse_ascend(FILE_T fh, guint8 *pd, struct ascend_phdr *phdr,
      of bytes on the wire, not actually how many bytes are in the trace.
      We won't know where the data ends until we run into the next packet. */
   if (caplen) {
-    if (header) {
-      header->start_time = start_time;
-      header->secs = secs;
-      header->usecs = usecs;
-      header->caplen = caplen;
-      header->len = wirelen;
+    if (ascend) {
+      if (! ascend->adjusted) {
+        ascend->adjusted = TRUE;
+        if (start_time != 0) {
+          /*
+           * Capture file contained a date and time.
+           * We do this only if this is the very first packet we've seen -
+           * i.e., if "ascend->adjusted" is false - because
+           * if we get a date and time after the first packet, we can't
+           * go back and adjust the time stamps of the packets we've already
+           * processed, and basing the time stamps of this and following
+           * packets on the time stamp from the file text rather than the
+           * ctime of the capture file means times before this and after
+           * this can't be compared.
+           */
+          ascend->inittime = start_time;
+        }
+        if (ascend->inittime > secs)
+          ascend->inittime -= secs;
+      }
+      phdr->presence_flags = WTAP_HAS_TS|WTAP_HAS_CAP_LEN;
+      phdr->ts.secs = secs + ascend->inittime;
+      phdr->ts.nsecs = usecs * 1000;
+      phdr->caplen = caplen;
+      phdr->len = wirelen;
+    }
+
+    /*
+     * For these types, the encapsulation we use is not WTAP_ENCAP_ASCEND,
+     * so set the pseudo-headers appropriately for the type (WTAP_ENCAP_ISDN
+     * or WTAP_ENCAP_ETHERNET).
+     */
+    switch(phdr->pseudo_header.ascend.type) {
+      case ASCEND_PFX_ISDN_X:
+        phdr->pseudo_header.isdn.uton = TRUE;
+        phdr->pseudo_header.isdn.channel = 0;
+        break;
+
+      case ASCEND_PFX_ISDN_R:
+        phdr->pseudo_header.isdn.uton = FALSE;
+        phdr->pseudo_header.isdn.channel = 0;
+        break;
+
+      case ASCEND_PFX_ETHER:
+        phdr->pseudo_header.eth.fcs_len = 0;
+        break;
     }
 
     return PARSED_RECORD;
diff --git a/wiretap/ascendtext.c b/wiretap/ascendtext.c
index d0b4e765c6..c7044a218a 100644
--- a/wiretap/ascendtext.c
+++ b/wiretap/ascendtext.c
@@ -76,12 +76,6 @@ static const ascend_magic_string ascend_magic[] = {
   { ASCEND_PFX_ETHER,	"ETHER" },
 };
 
-typedef struct {
-	time_t inittime;
-	int adjusted;
-	gint64 next_packet_seek_start;
-} ascend_t;
-
 static gboolean ascend_read(wtap *wth, int *err, gchar **err_info,
 	gint64 *data_offset);
 static gboolean ascend_seek_read(wtap *wth, gint64 seek_off,
@@ -169,8 +163,6 @@ int ascend_open(wtap *wth, int *err, gchar **err_info)
   gint64 offset;
   ws_statb64 statbuf;
   guint8 buf[ASCEND_MAX_PKT_LEN];
-  ascend_pkthdr header;
-  gint64 dummy_seek_start;
   ascend_t *ascend;
 
   /* We haven't yet allocated a data structure for our private stuff;
@@ -187,8 +179,7 @@ int ascend_open(wtap *wth, int *err, gchar **err_info)
 
   /* Do a trial parse of the first packet just found to see if we might really have an Ascend file */
   init_parse_ascend();
-  if (parse_ascend(wth->fh, buf, &wth->phdr.pseudo_header.ascend, &header,
-      &dummy_seek_start) != PARSED_RECORD) {
+  if (parse_ascend(NULL, wth->fh, &wth->phdr, buf) != PARSED_RECORD) {
     return 0;
   }
 
@@ -228,7 +219,7 @@ int ascend_open(wtap *wth, int *err, gchar **err_info)
     return -1;
   }
   ascend->inittime = statbuf.st_ctime;
-  ascend->adjusted = 0;
+  ascend->adjusted = FALSE;
   wth->tsprecision = WTAP_FILE_TSPREC_USEC;
 
   init_parse_ascend();
@@ -236,33 +227,12 @@ int ascend_open(wtap *wth, int *err, gchar **err_info)
   return 1;
 }
 
-static void config_pseudo_header(union wtap_pseudo_header *pseudo_head)
-{
-  switch(pseudo_head->ascend.type) {
-    case ASCEND_PFX_ISDN_X:
-      pseudo_head->isdn.uton = TRUE;
-      pseudo_head->isdn.channel = 0;
-      break;
-
-    case ASCEND_PFX_ISDN_R:
-      pseudo_head->isdn.uton = FALSE;
-      pseudo_head->isdn.channel = 0;
-      break;
-
-    case ASCEND_PFX_ETHER:
-      pseudo_head->eth.fcs_len = 0;
-      break;
-  }
-}
-
 /* Read the next packet; called from wtap_read(). */
 static gboolean ascend_read(wtap *wth, int *err, gchar **err_info,
 	gint64 *data_offset)
 {
   ascend_t *ascend = (ascend_t *)wth->priv;
   gint64 offset;
-  guint8 *buf = buffer_start_ptr(wth->frame_buffer);
-  ascend_pkthdr header;
 
   /* parse_ascend() will advance the point at which to look for the next
      packet's header, to just after the last packet's header (ie. at the
@@ -272,45 +242,17 @@ static gboolean ascend_read(wtap *wth, int *err, gchar **err_info,
                 SEEK_SET, err) == -1)
     return FALSE;
 
-    offset = ascend_seek(wth, err, err_info);
-    if (offset == -1)
-      return FALSE;
-  if (parse_ascend(wth->fh, buf, &wth->phdr.pseudo_header.ascend, &header,
-      &(ascend->next_packet_seek_start)) != PARSED_RECORD) {
+  offset = ascend_seek(wth, err, err_info);
+  if (offset == -1)
+    return FALSE;
+  buffer_assure_space(wth->frame_buffer, wth->snapshot_length);
+  if (parse_ascend(ascend, wth->fh, &wth->phdr,
+                   buffer_start_ptr(wth->frame_buffer)) != PARSED_RECORD) {
     *err = WTAP_ERR_BAD_FILE;
     *err_info = g_strdup((ascend_parse_error != NULL) ? ascend_parse_error : "parse error");
     return FALSE;
   }
 
-  buffer_assure_space(wth->frame_buffer, wth->snapshot_length);
-
-  config_pseudo_header(&wth->phdr.pseudo_header);
-
-  if (! ascend->adjusted) {
-    ascend->adjusted = 1;
-    if (header.start_time != 0) {
-      /*
-       * Capture file contained a date and time.
-       * We do this only if this is the very first packet we've seen -
-       * i.e., if "ascend->adjusted" is false - because
-       * if we get a date and time after the first packet, we can't
-       * go back and adjust the time stamps of the packets we've already
-       * processed, and basing the time stamps of this and following
-       * packets on the time stamp from the file text rather than the
-       * ctime of the capture file means times before this and after
-       * this can't be compared.
-       */
-      ascend->inittime = header.start_time;
-    }
-    if (ascend->inittime > header.secs)
-      ascend->inittime -= header.secs;
-  }
-  wth->phdr.presence_flags = WTAP_HAS_TS|WTAP_HAS_CAP_LEN;
-  wth->phdr.ts.secs = header.secs + ascend->inittime;
-  wth->phdr.ts.nsecs = header.usecs * 1000;
-  wth->phdr.caplen = header.caplen;
-  wth->phdr.len = header.len;
-
   *data_offset = offset;
   return TRUE;
 }
@@ -319,18 +261,15 @@ static gboolean ascend_seek_read(wtap *wth, gint64 seek_off,
 	struct wtap_pkthdr *phdr, guint8 *pd, int len _U_,
 	int *err, gchar **err_info)
 {
-  union wtap_pseudo_header *pseudo_head = &phdr->pseudo_header;
   ascend_t *ascend = (ascend_t *)wth->priv;
 
   if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
     return FALSE;
-  if (parse_ascend(wth->random_fh, pd, &pseudo_head->ascend, NULL,
-      &(ascend->next_packet_seek_start)) != PARSED_RECORD) {
+  if (parse_ascend(ascend, wth->random_fh, phdr, pd) != PARSED_RECORD) {
     *err = WTAP_ERR_BAD_FILE;
     *err_info = g_strdup((ascend_parse_error != NULL) ? ascend_parse_error : "parse error");
     return FALSE;
   }
 
-  config_pseudo_header(pseudo_head);
   return TRUE;
 }