fs/fs.c: correctly interpret the '(max)len' parameter to fs_read()

[karo-tx-uboot.git] / fs / fs.c

diff --git a/fs/fs.c b/fs/fs.c
index 827b143e85e5538f9a250565ce2a54b0455fdab8..0299c4b138760abc027139083fb1048f8aac28c9 100644 (file)
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -285,24 +285,30 @@ int fs_size(const char *filename, loff_t *size)
        return ret;
 }
 
-int fs_read(const char *filename, ulong addr, loff_t offset, loff_t len,
+int fs_read(const char *filename, ulong addr, loff_t offset, loff_t maxlen,
            loff_t *actread)
 {
        struct fstype_info *info = fs_get_info(fs_type);
        void *buf;
        int ret;
+       loff_t len;
 
-       /*
-        * We don't actually know how many bytes are being read, since len==0
-        * means read the whole file.
-        */
+       ret = info->size(filename, &len);
+       if (ret) {
+               printf("Failed to determine size of file %s: %d\n",
+                       filename, ret);
+               goto err;
+       }
+       if (maxlen == 0)
+               maxlen = len;
+       else if (len > maxlen)
+               printf("** File %s larger than buffer size; truncating to %llu of %llu bytes\n",
+                       filename, maxlen, len);
+       len = min(len, maxlen);
        buf = map_sysmem(addr, len);
        ret = info->read(filename, buf, offset, len, actread);
+err:
        unmap_sysmem(buf);
-
-       /* If we requested a specific number of bytes, check we got it */
-       if (ret == 0 && len && *actread != len)
-               printf("** %s shorter than offset + len **\n", filename);
        fs_close();
 
        return ret;