RE: [PATCH V2 1/1] mmc-utils: fix messy code printed

+ Avri

On Mon, 8 Feb 2021 at 03:30, Xingyu Wu [off-list ref] wrote:

quoted

Some vendors of eMMC use different format to define the
Firmware name. If the Firmware name uses character and if
it exceeds the printable range of ASCII (0x20~0x7e),
mmc-utils will print messy code. This change can fix the
messy code issue, if the firmware name is not printable,
print it out as hexadecimal, this change was verified on
chromium project.

Signed-off-by: Xingyu Wu <redacted>

Avri, can you please have a look at this and provide comments or your ack?

Kind regards
Uffe

quoted

---
 mmc_cmds.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/mmc_cmds.c b/mmc_cmds.c
index fb37189..d090a24 100644
--- a/mmc_cmds.c
+++ b/mmc_cmds.c

@@ -29,6 +29,7 @@
 #include <stdint.h>
 #include <assert.h>
 #include <linux/fs.h> /* for BLKGETSIZE */
+#include <ctype.h>

 #include "mmc.h"
 #include "mmc_cmds.h"

@@ -1758,8 +1759,16 @@ int do_read_extcsd(int nargs, char **argv)
        }

        if (ext_csd_rev >= 7) {

int i;
please don't mix declaration and code

quoted

-               printf("eMMC Firmware Version: %s\n",
-                       (char*)&ext_csd[EXT_CSD_FIRMWARE_VERSION]);
+               printf("eMMC Firmware Version:");

Maybe add a comment that will explain why 8 bytes: /* FIRMWARE_VERSION [261-254] */

quoted

+               for (int i = 0; i < 8; i++) {
+                       char c = ext_csd[EXT_CSD_FIRMWARE_VERSION + i];
+
+                       if (isprint(c))
+                               printf("%c", c);
+                       else if (c != 0)
+                               printf("\\x%02x", c);

else 
	break;
also why do you need the \\x?  %02x should work

Thanks,
Avri

quoted

+               }
+               printf("\n");
                printf("eMMC Life Time Estimation A

[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A]: 0x%02x\n",

quoted

                        ext_csd[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A]);
                printf("eMMC Life Time Estimation B

[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_B]: 0x%02x\n",

quoted

--
2.25.1