Check fread() results to avoid gcc 4.6 warnings

When compiling with gcc 4.6, some code in fw_cfg.c complains that fop_ret
is assigned but not used (which is true).  However, it looks like the
meaningless assignments to fop_ret were done to suppress other gcc warnings
due to the fact that fread() is labelled as warn_unused_result in glibc.

This patch avoids both errors, by actually checking the fread() result code
and dropping out with an error message if it fails.

Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
David Gibson 2011-08-01 16:49:59 +10:00 committed by Anthony Liguori
parent 8a6b0cd764
commit 257a737558

View File

@ -87,6 +87,13 @@ static FILE *probe_splashfile(char *filename, int *file_sizep, int *file_typep)
/* check magic ID */
fseek(fp, 0L, SEEK_SET);
fop_ret = fread(buf, 1, 2, fp);
if (fop_ret != 2) {
error_report("Could not read header from '%s': %s",
filename, strerror(errno));
fclose(fp);
fp = NULL;
return fp;
}
filehead_value = (buf[0] + (buf[1] << 8)) & 0xffff;
if (filehead_value == 0xd8ff) {
file_type = JPG_FILE;
@ -181,6 +188,12 @@ static void fw_cfg_bootsplash(FWCfgState *s)
boot_splash_filedata_size = file_size;
fseek(fp, 0L, SEEK_SET);
fop_ret = fread(boot_splash_filedata, 1, file_size, fp);
if (fop_ret != file_size) {
error_report("failed to read data from '%s'.",
boot_splash_filename);
fclose(fp);
return;
}
fclose(fp);
/* insert data */
if (file_type == JPG_FILE) {