1 files changed, 167 insertions, 0 deletions

diff --git a/lib/decompress_inflate.c b/lib/decompress_inflate.c
new file mode 100644
index 000000000000..839a329b4fc4
--- /dev/null
+++ b/lib/decompress_inflate.c
@@ -0,0 +1,167 @@
+#ifdef STATIC
+/* Pre-boot environment: included */
+
+/* prevent inclusion of _LINUX_KERNEL_H in pre-boot environment: lots
+ * errors about console_printk etc... on ARM */
+#define _LINUX_KERNEL_H
+
+#include "zlib_inflate/inftrees.c"
+#include "zlib_inflate/inffast.c"
+#include "zlib_inflate/inflate.c"
+
+#else /* STATIC */
+/* initramfs et al: linked */
+
+#include <linux/zutil.h>
+
+#include "zlib_inflate/inftrees.h"
+#include "zlib_inflate/inffast.h"
+#include "zlib_inflate/inflate.h"
+
+#include "zlib_inflate/infutil.h"
+
+#endif /* STATIC */
+
+#include <linux/decompress/mm.h>
+
+#define INBUF_LEN (16*1024)
+
+/* Included from initramfs et al code */
+STATIC int INIT gunzip(unsigned char *buf, int len,
+                       int(*fill)(void*, unsigned int),
+                       int(*flush)(void*, unsigned int),
+                       unsigned char *out_buf,
+                       int *pos,
+                       void(*error_fn)(char *x)) {
+        u8 *zbuf;
+        struct z_stream_s *strm;
+        int rc;
+        size_t out_len;
+
+        set_error_fn(error_fn);
+        rc = -1;
+        if (flush) {
+                out_len = 0x8000; /* 32 K */
+                out_buf = malloc(out_len);
+        } else {
+                out_len = 0x7fffffff; /* no limit */
+        }
+        if (!out_buf) {
+                error("Out of memory while allocating output buffer");
+                goto gunzip_nomem1;
+        }
+
+        if (buf)
+                zbuf = buf;
+        else {
+                zbuf = malloc(INBUF_LEN);
+                len = 0;
+        }
+        if (!zbuf) {
+                error("Out of memory while allocating input buffer");
+                goto gunzip_nomem2;
+        }
+
+        strm = malloc(sizeof(*strm));
+        if (strm == NULL) {
+                error("Out of memory while allocating z_stream");
+                goto gunzip_nomem3;
+        }
+
+        strm->workspace = malloc(flush ? zlib_inflate_workspacesize() :
+                                 sizeof(struct inflate_state));
+        if (strm->workspace == NULL) {
+                error("Out of memory while allocating workspace");
+                goto gunzip_nomem4;
+        }
+
+        if (len == 0)
+                len = fill(zbuf, INBUF_LEN);
+
+        /* verify the gzip header */
+        if (len < 10 ||
+           zbuf[0] != 0x1f || zbuf[1] != 0x8b || zbuf[2] != 0x08) {
+                if (pos)
+                        *pos = 0;
+                error("Not a gzip file");
+                goto gunzip_5;
+        }
+
+        /* skip over gzip header (1f,8b,08... 10 bytes total +
+         * possible asciz filename)
+         */
+        strm->next_in = zbuf + 10;
+        /* skip over asciz filename */
+        if (zbuf[3] & 0x8) {
+                while (strm->next_in[0])
+                        strm->next_in++;
+                strm->next_in++;
+        }
+        strm->avail_in = len - (strm->next_in - zbuf);
+
+        strm->next_out = out_buf;
+        strm->avail_out = out_len;
+
+        rc = zlib_inflateInit2(strm, -MAX_WBITS);
+
+        if (!flush) {
+                WS(strm)->inflate_state.wsize = 0;
+                WS(strm)->inflate_state.window = NULL;
+        }
+
+        while (rc == Z_OK) {
+                if (strm->avail_in == 0) {
+                        /* TODO: handle case where both pos and fill are set */
+                        len = fill(zbuf, INBUF_LEN);
+                        if (len < 0) {
+                                rc = -1;
+                                error("read error");
+                                break;
+                        }
+                        strm->next_in = zbuf;
+                        strm->avail_in = len;
+                }
+                rc = zlib_inflate(strm, 0);
+
+                /* Write any data generated */
+                if (flush && strm->next_out > out_buf) {
+                        int l = strm->next_out - out_buf;
+                        if (l != flush(out_buf, l)) {
+                                rc = -1;
+                                error("write error");
+                                break;
+                        }
+                        strm->next_out = out_buf;
+                        strm->avail_out = out_len;
+                }
+
+                /* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
+                if (rc == Z_STREAM_END) {
+                        rc = 0;
+                        break;
+                } else if (rc != Z_OK) {
+                        error("uncompression error");
+                        rc = -1;
+                }
+        }
+
+        zlib_inflateEnd(strm);
+        if (pos)
+                /* add + 8 to skip over trailer */
+                *pos = strm->next_in - zbuf+8;
+
+gunzip_5:
+        free(strm->workspace);
+gunzip_nomem4:
+        free(strm);
+gunzip_nomem3:
+        if (!buf)
+                free(zbuf);
+gunzip_nomem2:
+        if (flush)
+                free(out_buf);
+gunzip_nomem1:
+        return rc; /* returns Z_OK (0) if successful */
+}
+
+#define decompress gunzip