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-rw-r--r--lib/decompress_inflate.c167
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..163e66aea5f6
--- /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 = 0x8100; /* 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 - 10;
+
+ 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