Re: [Qemu-devel] [PATCH 1/2] vmdk: convert error reporting

[Fam Zheng <famz@redhat.com>]

On Thu, 10/10 12:39, Kevin Wolf wrote:
> Am 10.10.2013 um 09:20 hat Fam Zheng geschrieben:
> > Convert "fprintf(stderr,..." to error API by passing around errp to
> > functions those want to report error message.
> > 
> > There are 2 more "fprintf(stderr,..." remaining in read/write code path.
> > 
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> > ---
> >  block/vmdk.c | 42 +++++++++++++++++++++---------------------
> >  1 file changed, 21 insertions(+), 21 deletions(-)
> > 
> > diff --git a/block/vmdk.c b/block/vmdk.c
> > index 5d56e31..a98ad23 100644
> > --- a/block/vmdk.c
> > +++ b/block/vmdk.c
> > @@ -483,7 +483,7 @@ static int vmdk_init_tables(BlockDriverState *bs, VmdkExtent *extent)
> >  
> >  static int vmdk_open_vmfs_sparse(BlockDriverState *bs,
> >                                   BlockDriverState *file,
> > -                                 int flags)
> > +                                 int flags, Error **errp)
> >  {
> >      int ret;
> >      uint32_t magic;
> 
> The errp parameter is unused in this function. You should probably use
> error_setg_errno() for the failure cases.
> 
> Callers generally don't distinguish different error return codes, so
> converted functions could return void instead of int.
> 
> > @@ -514,11 +514,11 @@ static int vmdk_open_vmfs_sparse(BlockDriverState *bs,
> >  }
> >  
> >  static int vmdk_open_desc_file(BlockDriverState *bs, int flags,
> > -                               uint64_t desc_offset);
> > +                               uint64_t desc_offset, Error **errp);
> >  
> >  static int vmdk_open_vmdk4(BlockDriverState *bs,
> >                             BlockDriverState *file,
> > -                           int flags)
> > +                           int flags, Error **errp)
> >  {
> >      int ret;
> >      uint32_t magic;
> > @@ -534,7 +534,7 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
> >      if (header.capacity == 0) {
> >          uint64_t desc_offset = le64_to_cpu(header.desc_offset);
> >          if (desc_offset) {
> > -            return vmdk_open_desc_file(bs, flags, desc_offset << 9);
> > +            return vmdk_open_desc_file(bs, flags, desc_offset << 9, errp);
> >          }
> >      }
> >  
> > @@ -663,7 +663,7 @@ static int vmdk_parse_description(const char *desc, const char *opt_name,
> >  /* Open an extent file and append to bs array */
> >  static int vmdk_open_sparse(BlockDriverState *bs,
> >                              BlockDriverState *file,
> > -                            int flags)
> > +                            int flags, Error **errp)
> >  {
> >      uint32_t magic;
> >  
> > @@ -674,10 +674,10 @@ static int vmdk_open_sparse(BlockDriverState *bs,
> >      magic = be32_to_cpu(magic);
> >      switch (magic) {
> >          case VMDK3_MAGIC:
> > -            return vmdk_open_vmfs_sparse(bs, file, flags);
> > +            return vmdk_open_vmfs_sparse(bs, file, flags, errp);
> >              break;
> >          case VMDK4_MAGIC:
> > -            return vmdk_open_vmdk4(bs, file, flags);
> > +            return vmdk_open_vmdk4(bs, file, flags, errp);
> >              break;
> >          default:
> >              return -EMEDIUMTYPE;
> > @@ -686,7 +686,7 @@ static int vmdk_open_sparse(BlockDriverState *bs,
> >  }
> >  
> >  static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
> > -        const char *desc_file_path)
> > +                              const char *desc_file_path, Error **errp)
> >  {
> >      int ret;
> >      char access[11];
> > @@ -748,13 +748,13 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
> >              extent->flat_start_offset = flat_offset << 9;
> >          } else if (!strcmp(type, "SPARSE") || !strcmp(type, "VMFSSPARSE")) {
> >              /* SPARSE extent and VMFSSPARSE extent are both "COWD" sparse file*/
> > -            ret = vmdk_open_sparse(bs, extent_file, bs->open_flags);
> > +            ret = vmdk_open_sparse(bs, extent_file, bs->open_flags, errp);
> >              if (ret) {
> >                  bdrv_unref(extent_file);
> >                  return ret;
> >              }
> >          } else {
> > -            fprintf(stderr,
> > +            error_setg(errp,
> >                  "VMDK: Not supported extent type \"%s\""".\n", type);
> >              return -ENOTSUP;
> >          }
> > @@ -769,7 +769,7 @@ next_line:
> >  }
> >  
> >  static int vmdk_open_desc_file(BlockDriverState *bs, int flags,
> > -                               uint64_t desc_offset)
> > +                               uint64_t desc_offset, Error **errp)
> >  {
> >      int ret;
> >      char *buf = NULL;
> > @@ -798,13 +798,13 @@ static int vmdk_open_desc_file(BlockDriverState *bs, int flags,
> >          strcmp(ct, "vmfsSparse") &&
> >          strcmp(ct, "twoGbMaxExtentSparse") &&
> >          strcmp(ct, "twoGbMaxExtentFlat")) {
> > -        fprintf(stderr,
> > +        error_setg(errp,
> >                  "VMDK: Not supported image type \"%s\""".\n", ct);
> >          ret = -ENOTSUP;
> >          goto exit;
> >      }
> >      s->desc_offset = 0;
> > -    ret = vmdk_parse_extents(buf, bs, bs->file->filename);
> > +    ret = vmdk_parse_extents(buf, bs, bs->file->filename, errp);
> >  exit:
> >      g_free(buf);
> >      return ret;
> > @@ -816,10 +816,10 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
> >      int ret;
> >      BDRVVmdkState *s = bs->opaque;
> >  
> > -    if (vmdk_open_sparse(bs, bs->file, flags) == 0) {
> > +    if (vmdk_open_sparse(bs, bs->file, flags, errp) == 0) {
> >          s->desc_offset = 0x200;
> >      } else {
> > -        ret = vmdk_open_desc_file(bs, flags, 0);
> > +        ret = vmdk_open_desc_file(bs, flags, 0, errp);
> >          if (ret) {
> >              goto fail;
> >          }
> > @@ -1517,12 +1517,12 @@ static int vmdk_create_extent(const char *filename, int64_t filesize,
> >  }
> >  
> >  static int filename_decompose(const char *filename, char *path, char *prefix,
> > -        char *postfix, size_t buf_len)
> > +                              char *postfix, size_t buf_len, Error **errp)
> >  {
> >      const char *p, *q;
> >  
> >      if (filename == NULL || !strlen(filename)) {
> > -        fprintf(stderr, "Vmdk: no filename provided.\n");
> > +        error_setg(errp, "Vmdk: no filename provided");
> 
> Here we have a  "Vmdk:" prefix and the error message starts in lower
> case.
> 
> >          return VMDK_ERROR;
> >      }
> >      p = strrchr(filename, '/');
> > @@ -1597,7 +1597,7 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options,
> >          "ddb.adapterType = \"%s\"\n";
> >      Error *local_err = NULL;
> >  
> > -    if (filename_decompose(filename, path, prefix, postfix, PATH_MAX)) {
> > +    if (filename_decompose(filename, path, prefix, postfix, PATH_MAX, errp)) {
> >          return -EINVAL;
> >      }
> >      /* Read out options */
> > @@ -1623,7 +1623,7 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options,
> >                 strcmp(adapter_type, "buslogic") &&
> >                 strcmp(adapter_type, "lsilogic") &&
> >                 strcmp(adapter_type, "legacyESX")) {
> > -        fprintf(stderr, "VMDK: Unknown adapter type: '%s'.\n", adapter_type);
> > +        error_setg(errp, "VMDK: Unknown adapter type: '%s'", adapter_type);
> 
> Here it's "VMDK:" and upper case.
> 
> >          return -EINVAL;
> >      }
> >      if (strcmp(adapter_type, "ide") != 0) {
> > @@ -1639,7 +1639,7 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options,
> >                 strcmp(fmt, "twoGbMaxExtentSparse") &&
> >                 strcmp(fmt, "twoGbMaxExtentFlat") &&
> >                 strcmp(fmt, "streamOptimized")) {
> > -        fprintf(stderr, "VMDK: Unknown subformat: %s\n", fmt);
> > +        error_setg(errp, "VMDK: Unknown subformat: %s", fmt);
> >          return -EINVAL;
> >      }
> >      split = !(strcmp(fmt, "twoGbMaxExtentFlat") &&
> > @@ -1653,7 +1653,7 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options,
> >          desc_extent_line = "RW %lld SPARSE \"%s\"\n";
> >      }
> >      if (flat && backing_file) {
> > -        /* not supporting backing file for flat image */
> > +        error_setg(errp, "flat image can't have backing file");
> 
> No prefix at all and lower case.
> 
> Can we standardise on using no prefix and starting the error message
> with a capital letter?
> 
OK, good points. I'll fix them. Thanks.

Fam