[PATCH v2 12/13] env: Use memcpy() instead of ad-hoc code to copy variable value

Marek Behún
2021-10-13T15:48:14Z

From: Marek Behún <marek.behun@nic.cz>

Copy the value of the found variable into given buffer with memcpy()
instead of ad-hoc code.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
---
cmd/nvedit.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/cmd/nvedit.c b/cmd/nvedit.c
index 8989c85d20..7f094b3cd7 100644
--- a/cmd/nvedit.c
+++ b/cmd/nvedit.c
@@ -736,7 +736,7 @@ int env_get_f(const char *name, char *buf, unsigned len)

for (p = env; *p != '\0'; p = end + 1) {
const char *value;
- int n, res;
+ unsigned res;

for (end = p; *end != '\0'; ++end)
if (end - env >= CONFIG_ENV_SIZE)
@@ -747,20 +747,14 @@ int env_get_f(const char *name, char *buf, unsigned len)
continue;

res = end - value;
+ memcpy(buf, value, min(len, res + 1));

- /* found; copy out */
- for (n = 0; n < len; ++n, ++buf) {
- *buf = *value++;
- if (*buf == '\0')
- return res;
+ if (len <= res) {
+ buf[len - 1] = '\0';
+ printf("env_buf [%u bytes] too small for value of \"%s\"\n",
+ len, name);
}

- if (n)
- *--buf = '\0';
-
- printf("env_buf [%u bytes] too small for value of \"%s\"\n",
- len, name);
-
return res;
}

--
2.32.0