tools/env: complete environment device config early

Currently flash_read completes a crucial part of the environment
device configuration, the device type (mtd_type). This is rather
confusing as flash_io calls flash_read conditionally, and one might
think flash_write, which also makes use of mtd_type, gets called
before flash_read. But since flash_io is always called with O_RDONLY
first, this is not actually the case in reality.

However, it is much cleaner to complete and verify the config early
in parse_config. This also prepares the code for further extension.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Reviewed-by: Andreas Fenkart

diff --git a/tools/env/fw_env.c b/tools/env/fw_env.c
index 692abda7318fc07b2ae7b1fc0b14ef44c2e1f2a0..06d6865f3b30eb41318983eb45610a35a471e9b3 100644 (file)
--- a/tools/env/fw_env.c
+++ b/tools/env/fw_env.c
@@ -1021,41 +1021,10 @@ static int flash_write (int fd_current, int fd_target, int dev_target)
 
 static int flash_read (int fd)
 {
-       struct mtd_info_user mtdinfo;
-       struct stat st;
        int rc;
 
-       rc = fstat(fd, &st);
-       if (rc < 0) {
-               fprintf(stderr, "Cannot stat the file %s\n",
-                       DEVNAME(dev_current));
-               return -1;
-       }
-
-       if (S_ISCHR(st.st_mode)) {
-               rc = ioctl(fd, MEMGETINFO, &mtdinfo);
-               if (rc < 0) {
-                       fprintf(stderr, "Cannot get MTD information for %s\n",
-                               DEVNAME(dev_current));
-                       return -1;
-               }
-               if (mtdinfo.type != MTD_NORFLASH &&
-                   mtdinfo.type != MTD_NANDFLASH &&
-                   mtdinfo.type != MTD_DATAFLASH &&
-                   mtdinfo.type != MTD_UBIVOLUME) {
-                       fprintf (stderr, "Unsupported flash type %u on %s\n",
-                                mtdinfo.type, DEVNAME(dev_current));
-                       return -1;
-               }
-       } else {
-               memset(&mtdinfo, 0, sizeof(mtdinfo));
-               mtdinfo.type = MTD_ABSENT;
-       }
-
-       DEVTYPE(dev_current) = mtdinfo.type;
-
        rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
-                            DEVOFFSET (dev_current), mtdinfo.type);
+                           DEVOFFSET(dev_current), DEVTYPE(dev_current));
        if (rc != CUR_ENVSIZE)
                return -1;
 
@@ -1328,10 +1297,55 @@ int fw_env_open(struct env_opts *opts)
        return 0;
 }
 
+static int check_device_config(int dev)
+{
+       struct stat st;
+       int fd, rc = 0;
+
+       fd = open(DEVNAME(dev), O_RDONLY);
+       if (fd < 0) {
+               fprintf(stderr,
+                       "Cannot open %s: %s\n",
+                       DEVNAME(dev), strerror(errno));
+               return -1;
+       }
+
+       rc = fstat(fd, &st);
+       if (rc < 0) {
+               fprintf(stderr, "Cannot stat the file %s\n",
+                       DEVNAME(dev));
+               goto err;
+       }
+
+       if (S_ISCHR(st.st_mode)) {
+               struct mtd_info_user mtdinfo;
+               rc = ioctl(fd, MEMGETINFO, &mtdinfo);
+               if (rc < 0) {
+                       fprintf(stderr, "Cannot get MTD information for %s\n",
+                               DEVNAME(dev));
+                       goto err;
+               }
+               if (mtdinfo.type != MTD_NORFLASH &&
+                   mtdinfo.type != MTD_NANDFLASH &&
+                   mtdinfo.type != MTD_DATAFLASH &&
+                   mtdinfo.type != MTD_UBIVOLUME) {
+                       fprintf(stderr, "Unsupported flash type %u on %s\n",
+                               mtdinfo.type, DEVNAME(dev));
+                       goto err;
+               }
+               DEVTYPE(dev) = mtdinfo.type;
+       } else {
+               DEVTYPE(dev) = MTD_ABSENT;
+       }
+
+err:
+       close(fd);
+       return rc;
+}
 
 static int parse_config(struct env_opts *opts)
 {
-       struct stat st;
+       int rc;
 
        if (!opts)
                opts = &default_opts;
@@ -1375,25 +1389,21 @@ static int parse_config(struct env_opts *opts)
        HaveRedundEnv = 1;
 #endif
 #endif
-       if (stat (DEVNAME (0), &st)) {
-               fprintf (stderr,
-                       "Cannot access MTD device %s: %s\n",
-                       DEVNAME (0), strerror (errno));
-               return -1;
-       }
+       rc = check_device_config(0);
+       if (rc < 0)
+               return rc;
 
-       if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
-               fprintf (stderr,
-                       "Cannot access MTD device %s: %s\n",
-                       DEVNAME (1), strerror (errno));
-               return -1;
-       }
+       if (HaveRedundEnv) {
+               rc = check_device_config(1);
+               if (rc < 0)
+                       return rc;
 
-       if (HaveRedundEnv && ENVSIZE(0) != ENVSIZE(1)) {
-               ENVSIZE(0) = ENVSIZE(1) = min(ENVSIZE(0), ENVSIZE(1));
-               fprintf(stderr,
-                       "Redundant environments have inequal size, set to 0x%08lx\n",
-                       ENVSIZE(1));
+               if (ENVSIZE(0) != ENVSIZE(1)) {
+                       ENVSIZE(0) = ENVSIZE(1) = min(ENVSIZE(0), ENVSIZE(1));
+                       fprintf(stderr,
+                               "Redundant environments have inequal size, set to 0x%08lx\n",
+                               ENVSIZE(1));
+               }
        }
 
        usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);