*: introduce and use bb_unsetenv_and_free

function                                             old     new   delta
bb_unsetenv_and_free                                   -      17     +17
tcpudpsvd_main                                      1819    1810      -9
safe_setenv                                           58      47     -11
udhcp_run_script                                     630     616     -14
make_device                                         1683    1663     -20
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/4 up/down: 17/-54)            Total: -37 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

6 files changed, 11 insertions, 10 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 5e962fdb6..58719a85b 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -408,6 +408,7 @@ void xchdir(const char *path) FAST_FUNC;
 void xchroot(const char *path) FAST_FUNC;
 void xsetenv(const char *key, const char *value) FAST_FUNC;
 void bb_unsetenv(const char *key) FAST_FUNC;
+void bb_unsetenv_and_free(char *key) FAST_FUNC;
 void xunlink(const char *pathname) FAST_FUNC;
 void xstat(const char *pathname, struct stat *buf) FAST_FUNC;
 int xopen(const char *pathname, int flags) FAST_FUNC;
diff --git a/libbb/xfuncs_printf.c b/libbb/xfuncs_printf.c
index 03aeaaa38..f021493b1 100644
--- a/libbb/xfuncs_printf.c
+++ b/libbb/xfuncs_printf.c
@@ -323,6 +323,11 @@ void FAST_FUNC bb_unsetenv(const char *var)
         free(tp);
 }
 
+void FAST_FUNC bb_unsetenv_and_free(char *var)
+{
+        bb_unsetenv(var);
+        free(var);
+}
 
 // Die with an error message if we can't set gid.  (Because resource limits may
 // limit this user to a given number of processes, and if that fills up the
diff --git a/miscutils/crond.c b/miscutils/crond.c
index f51159233..4a3103cb9 100644
--- a/miscutils/crond.c
+++ b/miscutils/crond.c
@@ -264,8 +264,7 @@ static void safe_setenv(char **pvar_val, const char *var, const char *val)
         char *var_val = *pvar_val;
 
         if (var_val) {
-                bb_unsetenv(var_val);
-                free(var_val);
+                bb_unsetenv_and_free(var_val);
         }
         *pvar_val = xasprintf("%s=%s", var, val);
         putenv(*pvar_val);
diff --git a/networking/tcpudp.c b/networking/tcpudp.c
index 42845df0e..b32fad624 100644
--- a/networking/tcpudp.c
+++ b/networking/tcpudp.c
@@ -85,8 +85,7 @@ static void undo_xsetenv(void)
         char **pp = env_cur = &env_var[0];
         while (*pp) {
                 char *var = *pp;
-                bb_unsetenv(var);
-                free(var);
+                bb_unsetenv_and_free(var);
                 *pp++ = NULL;
         }
 }
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index c2b21c695..de1b79844 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -327,8 +327,7 @@ static void udhcp_run_script(struct dhcp_packet *packet, const char *name)
 
         for (curr = envp; *curr; curr++) {
                 log2(" %s", *curr);
-                bb_unsetenv(*curr);
-                free(*curr);
+                bb_unsetenv_and_free(*curr);
         }
         free(envp);
 }
diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index 217075660..b4042c07e 100644
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -374,10 +374,8 @@ static void make_device(char *path, int delete)
                                 putenv(s1);
                                 if (system(command) == -1)
                                         bb_perror_msg("can't run '%s'", command);
-                                unsetenv("SUBSYSTEM");
-                                free(s1);
-                                unsetenv("MDEV");
-                                free(s);
+                                bb_unsetenv_and_free(s1);
+                                bb_unsetenv_and_free(s);
                                 free(command);
                         }