tools/env: factor out environment_end function

instead of adhoc computation of the environment end,
use a function with a proper name

Signed-off-by: Andreas Fenkart <andreas.fenkart@digitalstrom.com>

diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index d27f57e251f654d4b204e1a7f3cfc8f9e875e7f7..90eb5fa4cb9bd2e756a8f6b6f2278d2998494d8d 100644 (file)
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -643,6 +643,18 @@ int fw_parse_script(char *fname, struct env_opts *opts)
        return ret;
 }
 
+/**
+ * environment_end() - compute offset of first byte right after environemnt
+ * @dev - index of enviroment buffer
+ * Return:
+ *  device offset of first byte right after environemnt
+ */
+off_t environment_end(int dev)
+{
+       /* environment is block aligned */
+       return DEVOFFSET(dev) + ENVSECTORS(dev) * DEVESIZE(dev);
+}
+
 /*
  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
  * 0   - block is good
@@ -683,7 +695,6 @@ static int flash_read_buf (int dev, int fd, void *buf, size_t count,
                                   0 on NOR */
        size_t processed = 0;   /* progress counter */
        size_t readlen = count; /* current read length */
-       off_t top_of_range;     /* end of the last block we may use */
        off_t block_seek;       /* offset inside the current block to the start
                                   of the data */
        loff_t blockstart;      /* running start of the current block -
@@ -702,19 +713,11 @@ static int flash_read_buf (int dev, int fd, void *buf, size_t count,
                 */
                blocklen = DEVESIZE (dev);
 
-               /*
-                * To calculate the top of the range, we have to use the
-                * global DEVOFFSET (dev), which can be different from offset
-                */
-               top_of_range = ((DEVOFFSET(dev) / blocklen) +
-                               ENVSECTORS (dev)) * blocklen;
-
                /* Limit to one block for the first read */
                if (readlen > blocklen - block_seek)
                        readlen = blocklen - block_seek;
        } else {
                blocklen = 0;
-               top_of_range = offset + count;
        }
 
        /* This only runs once on NOR flash */
@@ -723,7 +726,7 @@ static int flash_read_buf (int dev, int fd, void *buf, size_t count,
                if (rc < 0)             /* block test failed */
                        return -1;
 
-               if (blockstart + block_seek + readlen > top_of_range) {
+               if (blockstart + block_seek + readlen > environment_end(dev)) {
                        /* End of range is reached */
                        fprintf (stderr,
                                 "Too few good blocks within range\n");
@@ -783,7 +786,6 @@ static int flash_write_buf (int dev, int fd, void *buf, size_t count,
                                   below offset */
        off_t block_seek;       /* offset inside the erase block to the start
                                   of the data */
-       off_t top_of_range;     /* end of the last block we may use */
        loff_t blockstart;      /* running start of the current block -
                                   MEMGETBADBLOCK needs 64 bits */
        int rc;
@@ -793,7 +795,6 @@ static int flash_write_buf (int dev, int fd, void *buf, size_t count,
         */
        if (mtd_type == MTD_ABSENT) {
                blocklen = count;
-               top_of_range = offset + count;
                erase_len = blocklen;
                blockstart = offset;
                block_seek = 0;
@@ -801,13 +802,10 @@ static int flash_write_buf (int dev, int fd, void *buf, size_t count,
        } else {
                blocklen = DEVESIZE(dev);
 
-               top_of_range = ((DEVOFFSET(dev) / blocklen) +
-                                       ENVSECTORS(dev)) * blocklen;
-
                erase_offset = (offset / blocklen) * blocklen;
 
                /* Maximum area we may use */
-               erase_len = top_of_range - erase_offset;
+               erase_len = environment_end(dev) - erase_offset;
 
                blockstart = erase_offset;
                /* Offset inside a block */
@@ -882,7 +880,7 @@ static int flash_write_buf (int dev, int fd, void *buf, size_t count,
                if (rc < 0)             /* block test failed */
                        return rc;
 
-               if (blockstart + erasesize > top_of_range) {
+               if (blockstart + erasesize > environment_end(dev)) {
                        fprintf (stderr, "End of range reached, aborting\n");
                        return -1;
                }