[Qemu-devel] [PATCH 2/4] uImage: implement gzip support

[Hollis Blanchard]

Based on gzip uImage loading code from u-boot.

Signed-off-by: Jerone Young <address@hidden>
Signed-off-by: Hollis Blanchard <address@hidden>
---
 loader.c |  110 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 files changed, 106 insertions(+), 4 deletions(-)

diff --git a/loader.c b/loader.c
index 7f4e69c..c9cb906 100644
--- a/loader.c
+++ b/loader.c
@@ -26,6 +26,8 @@
 #include "sysemu.h"
 #include "uboot_image.h"
 
+#include <zlib.h>
+
 /* return the size or -1 if error */
 int get_image_size(const char *filename)
 {
@@ -345,10 +347,93 @@ static void bswap_uboot_header(uboot_image_header_t *hdr)
 #endif
 }
 
+/* gunzip functionality is derived from gunzip function
+ * in uboot source code
+ */
+
+#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
+
+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;
+}
+
 /* Load a U-Boot image.  */
 int load_uboot(const char *filename, target_ulong *ep, int *is_linux)
 {
-
     int fd;
     int size;
     uboot_image_header_t h;
@@ -374,9 +459,9 @@ int load_uboot(const char *filename, target_ulong *ep, int 
*is_linux)
         goto fail;
     }
 
-    /* TODO: Implement compressed images.  */
-    if (hdr->ih_comp != IH_COMP_NONE) {
-        fprintf(stderr, "Unable to load compressed u-boot images\n");
+    /* TODO bzip2 support */
+    if (hdr->ih_comp == IH_COMP_BZIP2) {
+        fprintf(stderr, "Unable to load bzip2 compressed u-boot images\n");
         goto fail;
     }
 
@@ -398,6 +483,23 @@ int load_uboot(const char *filename, target_ulong *ep, int 
*is_linux)
         goto fail;
     }
 
+    if (hdr->ih_comp == IH_COMP_GZIP) {
+        uint8_t *compressed_data;
+        size_t max_bytes = 2 * hdr->ih_size;
+        ssize_t bytes;
+
+        compressed_data = data;
+        data = qemu_malloc(max_bytes);
+
+        bytes = gunzip(data, max_bytes, compressed_data, hdr->ih_size);
+        qemu_free(compressed_data);
+        if (bytes < 0) {
+            fprintf(stderr, "Unable to decompress gzipped image!\n");
+            goto fail;
+        }
+        hdr->ih_size = bytes;
+    }
+
     cpu_physical_memory_write_rom(hdr->ih_load, data, hdr->ih_size);
     qemu_free(data);
 
-- 
1.5.6.5