Change wtap_read() API so that the data offset is set via a pointer, and

a "keep reading" boolean value is returned from the function.
This avoids having to hack around the fact that some file formats truly
do have records that start at offset 0. (i4btrace and csids have no
file header. Neither does the pppdump-style file that I'm looking at right now).

svn path=/trunk/; revision=2392

1 files changed, 11 insertions, 15 deletions

diff --git a/wiretap/lanalyzer.c b/wiretap/lanalyzer.c
index bf2966fc82..4df14843c9 100644
--- a/wiretap/lanalyzer.c
+++ b/wiretap/lanalyzer.c
@@ -1,6 +1,6 @@
 /* lanalyzer.c
  *
- * $Id: lanalyzer.c,v 1.24 2000/08/25 21:25:38 gram Exp $
+ * $Id: lanalyzer.c,v 1.25 2000/09/07 05:34:10 gram Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@xiexie.org>
@@ -47,7 +47,7 @@
 #define BOARD_325		226	/* LANalyzer 325 (Ethernet) */
 #define BOARD_325TR		227	/* LANalyzer 325TR (Token-ring) */
 
-static int lanalyzer_read(wtap *wth, int *err);
+static gboolean lanalyzer_read(wtap *wth, int *err, int *data_offset);
 static void lanalyzer_close(wtap *wth);
 
 int lanalyzer_open(wtap *wth, int *err)
@@ -199,7 +199,7 @@ int lanalyzer_open(wtap *wth, int *err)
 #define DESCRIPTOR_LEN	32
 
 /* Read the next packet */
-static int lanalyzer_read(wtap *wth, int *err)
+static gboolean lanalyzer_read(wtap *wth, int *err, int *data_offset)
 {
 	int		packet_size = 0;
 	int		bytes_read;
@@ -207,7 +207,6 @@ static int lanalyzer_read(wtap *wth, int *err)
 	char		LE_record_length[2];
 	guint16		record_type, record_length;
 	gchar		descriptor[DESCRIPTOR_LEN];
-	int		data_offset;
 	guint16		time_low, time_med, time_high, true_size;
 	double		t;
 
@@ -216,13 +215,10 @@ static int lanalyzer_read(wtap *wth, int *err)
 	bytes_read = file_read(LE_record_type, 1, 2, wth->fh);
 	if (bytes_read != 2) {
 		*err = file_error(wth->fh);
-		if (*err != 0)
-			return -1;
-		if (bytes_read != 0) {
+		if (*err == 0 && bytes_read != 0) {
 			*err = WTAP_ERR_SHORT_READ;
-			return -1;
 		}
-		return 0;
+		return FALSE;
 	}
 	wth->data_offset += 2;
 	bytes_read = file_read(LE_record_length, 1, 2, wth->fh);
@@ -230,7 +226,7 @@ static int lanalyzer_read(wtap *wth, int *err)
 		*err = file_error(wth->fh);
 		if (*err == 0)
 			*err = WTAP_ERR_SHORT_READ;
-		return -1;
+		return FALSE;
 	}
 	wth->data_offset += 2;
 
@@ -244,7 +240,7 @@ static int lanalyzer_read(wtap *wth, int *err)
 		g_message("lanalyzer: record type %u seen after trace summary record",
 		    record_type);
 		*err = WTAP_ERR_BAD_RECORD;
-		return -1;
+		return FALSE;
 	}
 	else {
 		packet_size = record_length - DESCRIPTOR_LEN;
@@ -257,13 +253,13 @@ static int lanalyzer_read(wtap *wth, int *err)
 		*err = file_error(wth->fh);
 		if (*err == 0)
 			*err = WTAP_ERR_SHORT_READ;
-		return -1;
+		return FALSE;
 	}
 	wth->data_offset += DESCRIPTOR_LEN;
 
 	/* Read the packet data */
 	buffer_assure_space(wth->frame_buffer, packet_size);
-	data_offset = wth->data_offset;
+	*data_offset = wth->data_offset;
 	errno = WTAP_ERR_CANT_READ;
 	bytes_read = file_read(buffer_start_ptr(wth->frame_buffer), 1,
 		packet_size, wth->fh);
@@ -272,7 +268,7 @@ static int lanalyzer_read(wtap *wth, int *err)
 		*err = file_error(wth->fh);
 		if (*err == 0)
 			*err = WTAP_ERR_SHORT_READ;
-		return -1;
+		return FALSE;
 	}
 	wth->data_offset += packet_size;
 
@@ -294,7 +290,7 @@ static int lanalyzer_read(wtap *wth, int *err)
 	wth->phdr.caplen = packet_size;
 	wth->phdr.pkt_encap = wth->file_encap;
 
-	return data_offset;
+	return TRUE;
 }
 
 static void