lib/zstd/zstd.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2021 Google LLC
   4  */
   5
   6 #define LOG_CATEGORY    LOGC_BOOT
   7
   8 #include <common.h>
   9 #include <abuf.h>
  10 #include <log.h>
  11 #include <malloc.h>
  12 #include <linux/zstd.h>
  13
  14 int zstd_decompress(struct abuf *in, struct abuf *out)
  15 {
  16         ZSTD_DStream *dstream;
  17         ZSTD_inBuffer in_buf;
  18         ZSTD_outBuffer out_buf;
  19         void *workspace;
  20         size_t wsize;
  21         int ret;
  22
  23         wsize = ZSTD_DStreamWorkspaceBound(abuf_size(in));
  24         workspace = malloc(wsize);
  25         if (!workspace) {
  26                 debug("%s: cannot allocate workspace of size %zu\n", __func__,
  27                         wsize);
  28                 return -ENOMEM;
  29         }
  30
  31         dstream = ZSTD_initDStream(abuf_size(in), workspace, wsize);
  32         if (!dstream) {
  33                 log_err("%s: ZSTD_initDStream failed\n", __func__);
  34                 ret = -EPERM;
  35                 goto do_free;
  36         }
  37
  38         in_buf.src = abuf_data(in);
  39         in_buf.pos = 0;
  40         in_buf.size = abuf_size(in);
  41
  42         out_buf.dst = abuf_data(out);
  43         out_buf.pos = 0;
  44         out_buf.size = abuf_size(out);
  45
  46         while (1) {
  47                 size_t res;
  48
  49                 res = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
  50                 if (ZSTD_isError(res)) {
  51                         ret = ZSTD_getErrorCode(res);
  52                         log_err("ZSTD_decompressStream error %d\n", ret);
  53                         goto do_free;
  54                 }
  55
  56                 if (in_buf.pos >= abuf_size(in) || !res)
  57                         break;
  58         }
  59
  60         ret = out_buf.pos;
  61 do_free:
  62         free(workspace);
  63         return ret;
  64 }