Fix bug with -cdf on junk crossing buffer boundary.
If the gzip stream ended one or two bytes before the buffer
boundary, the first few bytes of the following junk copied would
be incorrect.
diff --git a/pigz.c b/pigz.c
index 07dc8c8..1eb0a3d 100644
--- a/pigz.c
+++ b/pigz.c
@@ -514,7 +514,7 @@
int force; // true to overwrite, compress links, cat
int sync; // true to flush output file
int form; // gzip = 0, zlib = 1, zip = 2 or 3
- unsigned char magic1; // first byte of possible header when decoding
+ int magic1; // first byte of possible header when decoding
int recurse; // true to dive down into directory structure
char *sufx; // suffix to use (".gz" or user supplied)
char *name; // name for gzip or zip header
@@ -2570,7 +2570,6 @@
// Buffered reading macros for decompression and listing.
#define GET() (g.in_left == 0 && (g.in_eof || load() == 0) ? 0 : \
(g.in_left--, *g.in_next++))
-#define UNGET(n) (g.in_left += (n), g.in_next -= (n))
#define GET2() (tmp2 = GET(), tmp2 + ((unsigned)(GET()) << 8))
#define GET4() (tmp4 = GET2(), tmp4 + ((unsigned long)(GET2()) << 16))
#define SKIP(dist) \
@@ -2712,14 +2711,14 @@
// see if it's a gzip, zlib, or lzw file
g.form = -1;
g.magic1 = GET();
- if (g.in_eof)
+ if (g.in_eof) {
+ g.magic1 = -1;
return -1;
+ }
magic = (unsigned)g.magic1 << 8;
magic += GET();
- if (g.in_eof) {
- UNGET(1);
+ if (g.in_eof)
return -2;
- }
if (magic % 31 == 0 && (magic & 0x8f20) == 0x0800) {
// it's zlib
g.form = 1;
@@ -2778,7 +2777,8 @@
return g.in_eof ? -3 : (int)method;
}
if (magic != 0x1f8b) { // not gzip
- UNGET(2);
+ g.in_left++; // return the second byte
+ g.in_next--;
return -2;
}
@@ -3075,6 +3075,12 @@
// --- copy input to output (when acting like cat) ---
local void cat(void) {
+ // copy the first header byte read, if any
+ if (g.magic1 != -1) {
+ unsigned char buf[1] = {g.magic1};
+ g.out_tot += writen(g.outd, buf, 1);
+ }
+
// copy the remainder of the input to the output
while (g.in_left) {
g.out_tot += writen(g.outd, g.in_next, g.in_left);
