tools/envcrc: add --binary option to export embedded env

The --binary option to envcrc can be used to export the embedded env as a
binary blob so that it can be manipulated/examined/whatever externally.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/tools/envcrc.c b/tools/envcrc.c
index 4334cdf..5b0f7cd 100644 (file)
--- a/tools/envcrc.c
+++ b/tools/envcrc.c
@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 
 #ifndef __ASSEMBLY__
@@ -77,19 +78,56 @@ extern unsigned char environment;
 int main (int argc, char **argv)
 {
 #ifdef ENV_IS_EMBEDDED
+       unsigned char pad = 0x00;
        uint32_t crc;
        unsigned char *envptr = &environment,
                *dataptr = envptr + ENV_HEADER_SIZE;
        unsigned int datasize = ENV_SIZE;
+       unsigned int eoe;
+
+       if (argv[1] && !strncmp(argv[1], "--binary", 8)) {
+               int ipad = 0xff;
+               if (argv[1][8] == '=')
+                       sscanf(argv[1] + 9, "%i", &ipad);
+               pad = ipad;
+       }
+
+       if (pad) {
+               /* find the end of env */
+               for (eoe = 0; eoe < datasize - 1; ++eoe)
+                       if (!dataptr[eoe] && !dataptr[eoe+1]) {
+                               eoe += 2;
+                               break;
+                       }
+               if (eoe < datasize - 1)
+                       memset(dataptr + eoe, pad, datasize - eoe);
+       }
 
        crc = crc32 (0, dataptr, datasize);
 
        /* Check if verbose mode is activated passing a parameter to the program */
        if (argc > 1) {
-               printf ("CRC32 from offset %08X to %08X of environment = %08X\n",
-                       (unsigned int) (dataptr - envptr),
-                       (unsigned int) (dataptr - envptr) + datasize,
-                       crc);
+               if (!strncmp(argv[1], "--binary", 8)) {
+                       int le = (argc > 2 ? !strcmp(argv[2], "le") : 1);
+                       size_t i, start, end, step;
+                       if (le) {
+                               start = 0;
+                               end = ENV_HEADER_SIZE;
+                               step = 1;
+                       } else {
+                               start = ENV_HEADER_SIZE - 1;
+                               end = -1;
+                               step = -1;
+                       }
+                       for (i = start; i != end; i += step)
+                               printf("%c", (crc & (0xFF << (i * 8))) >> (i * 8));
+                       fwrite(dataptr, 1, datasize, stdout);
+               } else {
+                       printf("CRC32 from offset %08X to %08X of environment = %08X\n",
+                               (unsigned int) (dataptr - envptr),
+                               (unsigned int) (dataptr - envptr) + datasize,
+                               crc);
+               }
        } else {
                printf ("0x%08X\n", crc);
        }