From bed2510078b46c35b95941e59327b1008e4bd176 Mon Sep 17 00:00:00 2001
From: "sgunderson@bigfoot.com" <>
Date: Sun, 31 May 2009 20:15:06 +0200
Subject: [PATCH] Let the bit source alert about EOF as soon as we have started
 eating into padding. Finally fixes EOF issues in driver.

---
 bitsource.c | 23 +++++++++++++----------
 bitsource.h |  2 ++
 driver.c    |  2 +-
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/bitsource.c b/bitsource.c
index 7a4ea4a..b1593aa 100644
--- a/bitsource.c
+++ b/bitsource.c
@@ -45,17 +45,20 @@ void possibly_refill_slow_path(struct bit_source* source, unsigned num_bits)
 			fprintf(stderr, "Input function returned error\n");
 			exit(1);
 		}
-		if (bytes_read == 0 && source->padding_bytes_available > 0) {
-			unsigned padding_to_add = source->padding_bytes_available;
-			if (padding_to_add > bytes_to_read) {
-				padding_to_add = bytes_to_read;
+		if (bytes_read == 0) {
+			source->source_eof = true;
+			if (source->padding_bytes_available > 0) {
+				unsigned padding_to_add = source->padding_bytes_available;
+				if (padding_to_add > bytes_to_read) {
+					padding_to_add = bytes_to_read;
+				}
+				memset(source->bytes + source->bytes_available, 0, padding_to_add);
+				source->padding_bytes_available -= padding_to_add;
+				source->bytes_available += padding_to_add;
+			} else {
+				fprintf(stderr, "Premature EOF\n");
+				exit(1);
 			}
-			memset(source->bytes + source->bytes_available, 0, padding_to_add);
-			source->padding_bytes_available -= padding_to_add;
-			source->bytes_available += padding_to_add;
-		} else if (bytes_read == 0) {
-			fprintf(stderr, "Premature EOF\n");
-			exit(1);
 		} else {
 			source->bytes_available += bytes_read;
 		}
diff --git a/bitsource.h b/bitsource.h
index ae29b4c..60744b3 100644
--- a/bitsource.h
+++ b/bitsource.h
@@ -2,6 +2,7 @@
 #define _BITSOURCE_H 1
 
 #include <assert.h>
+#include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <sys/types.h>
@@ -45,6 +46,7 @@ struct bit_source {
 	// Data source.
 	input_func_t* input_func;
 	void* userdata;
+	bool source_eof;
 };
 
 void init_bit_source(struct bit_source* source, input_func_t* input_func,
diff --git a/driver.c b/driver.c
index aa803d6..35934da 100644
--- a/driver.c
+++ b/driver.c
@@ -151,7 +151,7 @@ void read_scan(struct byte_source* source, struct jpeg_image* image, huffman_tab
 		
 	unsigned mcu_x = 0, mcu_y = 0;
 
-	for ( ;; ) {
+	while (!bits.source_eof) {
 		for (unsigned c = 0; c < num_components; ++c) {
 			unsigned cn = component_num[c];
 			unsigned stride = image->num_blocks_horizontal * image->hsample[cn] * DCTSIZE;
-- 
2.39.2