[PATCH 09/10] env: Use string pointer instead of indexes in env_get_f()

[Marek Behún]

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

Since we no longer use env_get_char() to access n-th character of
linearized environment data, but rather access the arrays themselves, we
can convert the iteration to use string pointers instead of position
indexes.

Signed-off-by: Marek Behún <marek.behun at nic.cz>
---
 cmd/nvedit.c | 37 ++++++++++++++++++-------------------
 1 file changed, 18 insertions(+), 19 deletions(-)

diff --git a/cmd/nvedit.c b/cmd/nvedit.c
index 51b9e4ffa4..455783dccc 100644
--- a/cmd/nvedit.c
+++ b/cmd/nvedit.c
@@ -706,16 +706,16 @@ char *from_env(const char *envvar)
 	return ret;
 }
 
-static int env_match(const char *env, const char *s1, int i2)
+static const char *matching_name_get_value(const char *p, const char *name)
 {
-	while (*s1 != '\0' && *s1 == env[i2++])
-		if (*s1++ == '=')
-			return i2;
+	while (*name != '\0' && *name == *p++)
+		if (*name++ == '=')
+			return p;
 
-	if (*s1 == '\0' && env[i2-1] == '=')
-		return i2;
+	if (*name == '\0' && p[-1] == '=')
+		return p;
 
-	return -1;
+	return NULL;
 }
 
 /*
@@ -723,8 +723,7 @@ static int env_match(const char *env, const char *s1, int i2)
  */
 int env_get_f(const char *name, char *buf, unsigned len)
 {
-	const char *env;
-	int i, nxt;
+	const char *env, *p, *nxt;
 
 	if (name == NULL || *name == '\0')
 		return -1;
@@ -734,26 +733,26 @@ int env_get_f(const char *name, char *buf, unsigned len)
 	else
 		env = (const char *)gd->env_addr;
 
-	for (i = 0; env[i] != '\0'; i = nxt + 1) {
-		int val, n;
+	for (p = env; *p != '\0'; p = nxt + 1) {
+		const char *value;
+		unsigned copied;
 
-		for (nxt = i; env[nxt] != '\0'; ++nxt)
-			if (nxt >= CONFIG_ENV_SIZE)
+		for (nxt = p; *nxt != '\0'; ++nxt)
+			if (p - env >= CONFIG_ENV_SIZE)
 				return -1;
 
-		val = env_match(env, name, i);
-		if (val < 0)
+		value = matching_name_get_value(p, name);
+		if (value == NULL)
 			continue;
 
-		/* found; copy out */
-		n = strncpy(buf, &env[val], len) - buf;
-		if (len && n == len) {
+		copied = strncpy(buf, value, len) - buf;
+		if (len && copied == len) {
 			buf[len - 1] = '\0';
 			printf("env_buf [%u bytes] too small for value of \"%s\"\n",
 			       len, name);
 		}
 
-		return n;
+		return copied;
 	}
 
 	return -1;
-- 
2.32.0