+
+#define ZALLOC_ALIGNMENT 16
+
+static void *zalloc(void *x, unsigned items, unsigned size)
+{
+ void *p;
+
+ size *= items;
+ size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);
+
+ p = qemu_malloc(size);
+
+ return (p);
+}
+
+static void zfree(void *x, void *addr, unsigned nb)
+{
+ qemu_free(addr);
+}
+
+
+#define HEAD_CRC 2
+#define EXTRA_FIELD 4
+#define ORIG_NAME 8
+#define COMMENT 0x10
+#define RESERVED 0xe0
+
+#define DEFLATED 8
+
+/* This is the maximum in uboot, so if a uImage overflows this, it would
+ * overflow on real hardware too. */
+#define UBOOT_MAX_GUNZIP_BYTES 0x800000
+
+static ssize_t gunzip(void *dst, size_t dstlen, uint8_t *src,
+ size_t srclen)
+{
+ z_stream s;
+ ssize_t dstbytes;
+ int r, i, flags;
+
+ /* skip header */
+ i = 10;
+ flags = src[3];
+ if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
+ puts ("Error: Bad gzipped data\n");
+ return -1;
+ }
+ if ((flags & EXTRA_FIELD) != 0)
+ i = 12 + src[10] + (src[11] << 8);
+ if ((flags & ORIG_NAME) != 0)
+ while (src[i++] != 0)
+ ;
+ if ((flags & COMMENT) != 0)
+ while (src[i++] != 0)
+ ;
+ if ((flags & HEAD_CRC) != 0)
+ i += 2;
+ if (i >= srclen) {
+ puts ("Error: gunzip out of data in header\n");
+ return -1;
+ }
+
+ s.zalloc = zalloc;
+ s.zfree = (free_func)zfree;
+
+ r = inflateInit2(&s, -MAX_WBITS);
+ if (r != Z_OK) {
+ printf ("Error: inflateInit2() returned %d\n", r);
+ return (-1);
+ }
+ s.next_in = src + i;
+ s.avail_in = srclen - i;
+ s.next_out = dst;
+ s.avail_out = dstlen;
+ r = inflate(&s, Z_FINISH);
+ if (r != Z_OK && r != Z_STREAM_END) {
+ printf ("Error: inflate() returned %d\n", r);
+ return -1;
+ }
+ dstbytes = s.next_out - (unsigned char *) dst;
+ inflateEnd(&s);
+
+ return dstbytes;
+}
+