env: Simplify env_match() and inline into env_get_f()

In the past the env_match() function was used to match envs with
- name, i.e. string "name"
- variable assignment, i.e. string "name=other_value"

The latter is not the case anymore, since the env_match() function is
now used only in env_get_f(), and so we can simplify the function into
a simple strncmp() with an additional comparison to '='.

Let's do this, and since the resulting function is quite simple, let's
also inline its code into env_get_f().

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/cmd/nvedit.c b/cmd/nvedit.c
index ffcfb55..272d0c7 100644 (file)
--- a/cmd/nvedit.c
+++ b/cmd/nvedit.c
@@ -706,28 +706,19 @@ char *from_env(const char *envvar)
        return ret;
 }
 
-static const char *env_match(const char *p, const char *s1)
-{
-       while (*s1 == *p++)
-               if (*s1++ == '=')
-                       return p;
-
-       if (*s1 == '\0' && p[-1] == '=')
-               return p;
-
-       return NULL;
-}
-
 /*
  * Look up variable from environment for restricted C runtime env.
  */
 int env_get_f(const char *name, char *buf, unsigned len)
 {
        const char *env, *p, *end;
+       size_t name_len;
 
        if (name == NULL || *name == '\0')
                return -1;
 
+       name_len = strlen(name);
+
        if (gd->env_valid == ENV_INVALID)
                env = (const char *)default_environment;
        else
@@ -741,9 +732,9 @@ int env_get_f(const char *name, char *buf, unsigned len)
                        if (end - env >= CONFIG_ENV_SIZE)
                                return -1;
 
-               value = env_match(p, name);
-               if (value == NULL)
+               if (strncmp(name, p, name_len) || p[name_len] != '=')
                        continue;
+               value = &p[name_len + 1];
 
                res = end - value;
                memcpy(buf, value, min(len, res + 1));