From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 28 Oct 2009 21:02:28 +0000 (+0000)
Subject: potential fix for zoom-related crash involving array overrun during peak generation
X-Git-Tag: 2.8.16~675
X-Git-Url: https://main.carlh.net/gitweb/?a=commitdiff_plain;h=836591b6b5aa8d0e439004152e3941150f0fb538;p=ardour.git

potential fix for zoom-related crash involving array overrun during peak generation

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@5960 d708f5d6-7413-0410-9779-e7cbd77b26cf
---

diff --git a/libs/ardour/audiosource.cc b/libs/ardour/audiosource.cc
index 36a667d109..5bd9712762 100644
--- a/libs/ardour/audiosource.cc
+++ b/libs/ardour/audiosource.cc
@@ -523,21 +523,28 @@ AudioSource::read_peaks_with_fpp (PeakData *peaks, nframes_t npeaks, nframes_t s
 
 			if (i == frames_read) {
 				
-				to_read = min (chunksize, (_length - current_frame));
+				if (current_frame >= _length) {
 
-				if (to_read == 0) {
-					/* XXX ARGH .. out by one error ... need to figure out why this happens
-					   and fix it rather than do this band-aid move.
+					/* hmm, error condition - we've reached the end of the file
+					   without generating all the peak data. cook up a zero-filled
+					   data buffer and then use it. this is simpler than
+					   adjusting zero_fill and npeaks and then breaking out of 
+					   this loop early 
 					*/
-					zero_fill = npeaks - nvisual_peaks;
-					break;
-				}
 
-				if ((frames_read = read_unlocked (raw_staging, current_frame, to_read)) == 0) {
-					error << string_compose(_("AudioSource[%1]: peak read - cannot read %2 samples at offset %3 of %4 (%5)"),
-								_name, to_read, current_frame, _length, strerror (errno)) 
-					      << endmsg;
-					goto out;
+					memset (raw_staging, 0, sizeof (Sample) * chunksize);
+
+				} else {
+					
+					to_read = min (chunksize, (_length - current_frame));
+					
+					
+					if ((frames_read = read_unlocked (raw_staging, current_frame, to_read)) == 0) {
+						error << string_compose(_("AudioSource[%1]: peak read - cannot read %2 samples at offset %3 of %4 (%5)"),
+									_name, to_read, current_frame, _length, strerror (errno)) 
+						      << endmsg;
+						goto out;
+					}
 				}
 					
 				i = 0;