From 3112ce0ce8195880aec5e9373434a85e21c3e1af Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marek=20Beh=C3=BAn?= Date: Sun, 17 Oct 2021 17:36:35 +0200 Subject: [PATCH] env: Make return value of env_get_f() behave like sprintf() on success MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Currently the env_get_f() function's return value behaves weirdly: it returns the number of bytes written into `buf`, but whether this is excluding the terminating NULL-byte or including it depends on whether there was enough space in `buf`. Change the function to always return the actual length of the value of the environment variable (excluding the terminating NULL-byte) on success. This makes it behave like sprintf(). All users of this function in U-Boot are compatible with this change. Signed-off-by: Marek Behún Reviewed-by: Simon Glass --- cmd/nvedit.c | 8 +++++--- include/env.h | 6 ++---- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/cmd/nvedit.c b/cmd/nvedit.c index 063cc76282..527b522e9e 100644 --- a/cmd/nvedit.c +++ b/cmd/nvedit.c @@ -735,7 +735,7 @@ int env_get_f(const char *name, char *buf, unsigned len) for (p = env; *p != '\0'; p = end + 1) { const char *value; - int n; + int n, res; for (end = p; *end != '\0'; ++end) if (end - env >= CONFIG_ENV_SIZE) @@ -745,11 +745,13 @@ int env_get_f(const char *name, char *buf, unsigned len) if (value == NULL) continue; + res = end - value; + /* found; copy out */ for (n = 0; n < len; ++n, ++buf) { *buf = *value++; if (*buf == '\0') - return n; + return res; } if (n) @@ -758,7 +760,7 @@ int env_get_f(const char *name, char *buf, unsigned len) printf("env_buf [%u bytes] too small for value of \"%s\"\n", len, name); - return n; + return res; } return -1; diff --git a/include/env.h b/include/env.h index 220ab979d9..ee5e30d036 100644 --- a/include/env.h +++ b/include/env.h @@ -120,10 +120,8 @@ char *from_env(const char *envvar); * support reading the value (slowly) and some will not. * * @varname: Variable to look up - * @return number of bytes written into @buf, excluding the terminating - * NULL-byte if there was enough space in @buf, and including the - * terminating NULL-byte if there wasn't enough space, or -1 if the - * variable is not found + * @return actual length of the variable value excluding the terminating + * NULL-byte, or -1 if the variable is not found */ int env_get_f(const char *name, char *buf, unsigned int len); -- 2.39.5