2018-01-27 12:45:26 (UTC-02:00)

Marcel Rodrigues <marcelgmr@gmail.com>

Write partial byte iif offset % 8 != 0.

The function end_key() flushes the  last non-empty sub-block in a block.
The length of  this sub-block depends on whether there  are bits waiting
to fill up a temporary byte. If gif->offset is a multiple of 8, then all
bits  were  already  packed  into  bytes  and  written  to  gif->buffer.
Otherwise, there are 8 - gif->offset % 8 bits that need to be written in
the buffer, adding one byte to the sub-block.

diff --git a/gifenc.c b/gifenc.c
index 9a35203..6403152 100644
--- a/gifenc.c
+++ b/gifenc.c
@@ -166,7 +166,8 @@ end_key(ge_GIF *gif)
 {
     int byte_offset;
     byte_offset = gif->offset / 8;
-    gif->buffer[byte_offset] = gif->partial & 0xFF;
+    if (gif->offset % 8)
+        gif->buffer[byte_offset++] = gif->partial & 0xFF;
     write(gif->fd, (uint8_t []) {byte_offset}, 1);
     write(gif->fd, gif->buffer, byte_offset);
     write(gif->fd, "\0", 1);