diff options
Diffstat (limited to 'lib/decompress_inflate.c')
| -rw-r--r-- | lib/decompress_inflate.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/lib/decompress_inflate.c b/lib/decompress_inflate.c new file mode 100644 index 000000000..d4c789163 --- /dev/null +++ b/lib/decompress_inflate.c @@ -0,0 +1,184 @@ +#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" +#include <linux/decompress/inflate.h> + +#endif /* STATIC */ + +#include <linux/decompress/mm.h> + +#define GZIP_IOBUF_SIZE (16*1024) + +static long INIT nofill(void *buffer, unsigned long len) +{ + return -1; +} + +/* Included from initramfs et al code */ +STATIC int INIT gunzip(unsigned char *buf, long len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *out_buf, + long *pos, + void(*error)(char *x)) { + u8 *zbuf; + struct z_stream_s *strm; + int rc; + size_t out_len; + + rc = -1; + if (flush) { + out_len = 0x8000; /* 32 K */ + out_buf = malloc(out_len); + } else { + out_len = ((size_t)~0) - (size_t)out_buf; /* no limit */ + } + if (!out_buf) { + error("Out of memory while allocating output buffer"); + goto gunzip_nomem1; + } + + if (buf) + zbuf = buf; + else { + zbuf = malloc(GZIP_IOBUF_SIZE); + 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 (!fill) + fill = nofill; + + if (len == 0) + len = fill(zbuf, GZIP_IOBUF_SIZE); + + /* 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; + strm->avail_in = len - 10; + /* skip over asciz filename */ + if (zbuf[3] & 0x8) { + do { + /* + * If the filename doesn't fit into the buffer, + * the file is very probably corrupt. Don't try + * to read more data. + */ + if (strm->avail_in == 0) { + error("header error"); + goto gunzip_5; + } + --strm->avail_in; + } while (*strm->next_in++); + } + + 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, GZIP_IOBUF_SIZE); + 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) { + long 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 |