mtd: trx: use separated buffer for TRX header

We plan to adjust usage of the main buffer to allow reading custom
amount of data for CRC32. This means we need another buffer that will be
always block aligned.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
SVN-Revision: 49316

diff --git a/package/system/mtd/src/trx.c b/package/system/mtd/src/trx.c
index 00c4d6c0b50b7006f5ac503b98db2320000ae63b..f310f51087e5f8eec99565e42a7cc3697fe7aec1 100644 (file)
--- a/package/system/mtd/src/trx.c
+++ b/package/system/mtd/src/trx.c
@@ -152,6 +152,7 @@ mtd_fixtrx(const char *mtd, size_t offset)
 {
        int fd;
        struct trx_header *trx;
+       char *first_block;
        char *buf;
        ssize_t res;
        size_t block_offset;
@@ -173,19 +174,19 @@ mtd_fixtrx(const char *mtd, size_t offset)
                exit(1);
        }
 
-       buf = malloc(erasesize);
-       if (!buf) {
+       first_block = malloc(erasesize);
+       if (!first_block) {
                perror("malloc");
                exit(1);
        }
 
-       res = pread(fd, buf, erasesize, block_offset);
+       res = pread(fd, first_block, erasesize, block_offset);
        if (res != erasesize) {
                perror("pread");
                exit(1);
        }
 
-       trx = (struct trx_header *) (buf + offset);
+       trx = (struct trx_header *)(first_block + offset);
        if (trx->magic != STORE32_LE(0x30524448)) {
                fprintf(stderr, "No trx magic found\n");
                exit(1);
@@ -198,6 +199,18 @@ mtd_fixtrx(const char *mtd, size_t offset)
                return 0;
        }
 
+       buf = malloc(erasesize);
+       if (!buf) {
+               perror("malloc");
+               exit(1);
+       }
+
+       res = pread(fd, buf, erasesize, block_offset);
+       if (res != erasesize) {
+               perror("pread");
+               exit(1);
+       }
+
        trx->len = STORE32_LE(erasesize - offset);
 
        trx->crc32 = STORE32_LE(crc32buf((char*) &trx->flag_version, erasesize - offset - 3*4));
@@ -209,7 +222,7 @@ mtd_fixtrx(const char *mtd, size_t offset)
        if (quiet < 2)
                fprintf(stderr, "New crc32: 0x%x, rewriting block\n", trx->crc32);
 
-       if (pwrite(fd, buf, erasesize, block_offset) != erasesize) {
+       if (pwrite(fd, first_block, erasesize, block_offset) != erasesize) {
                fprintf(stderr, "Error writing block (%s)\n", strerror(errno));
                exit(1);
        }