refactored part of expand_env_esc() into mch_get_user_directory()

src/misc1.c

@@ -2895,25 +2895,14 @@ expand_env_esc (
         *var = NUL;
 # ifdef UNIX
         /*
-         * If the system supports getpwnam(), use it.
+         * Use mch_get_user_directory() to get the user directory.
-         * Otherwise, or if getpwnam() fails, the shell is used to
+         * If this function fails, the shell is used to
          * expand ~user. This is slower and may fail if the shell
          * does not support ~user (old versions of /bin/sh).
          */
-#  if defined(HAVE_GETPWNAM) && defined(HAVE_PWD_H)
+        var = (char_u *)mch_get_user_directory((char *)dst + 1);
-        {
+        mustfree = TRUE;
-          struct passwd *pw;
-
-          /* Note: memory allocated by getpwnam() is never freed.
-           * Calling endpwent() apparently doesn't help. */
-          pw = getpwnam((char *)dst + 1);
-          if (pw != NULL)
-            var = (char_u *)pw->pw_dir;
-          else
-            var = NULL;
-        }
         if (var == NULL)
-#  endif
         {
           expand_T xpc;
 

src/os/os.h

@@ -16,5 +16,6 @@ char *mch_getenvname_at_index(size_t index);
 int mch_get_usernames(garray_T *usernames);
 int mch_get_user_name(char *s, size_t len);
 int mch_get_uname(uid_t uid, char *s, size_t len);
+char *mch_get_user_directory(const char *name);
 
 #endif

src/os/users.c

@@ -84,3 +84,25 @@ int mch_get_uname(uid_t uid, char *s, size_t len)
   return FAIL; // a number is not a name
 }
 
+/*
+ * Returns the user directory for the given username.
+ * The caller has to free() the returned string.
+ * If the username is not found, NULL is returned.
+ */
+char *mch_get_user_directory(const char *name)
+{
+#if defined(HAVE_GETPWNAM) && defined(HAVE_PWD_H)
+  struct passwd *pw;
+  if (name == NULL) {
+    return NULL;
+  }
+  pw = getpwnam(name);
+  if (pw != NULL) {
+    // save the string from the static passwd entry into malloced memory
+    char *user_directory = (char *)vim_strsave((char_u *)pw->pw_dir);
+    return user_directory;
+  }
+#endif
+  return NULL;
+}
+

src/os_unix_defs.h

@@ -121,10 +121,6 @@
 
 #define BASENAMELEN     (MAXNAMLEN - 5)
 
-#ifdef HAVE_PWD_H
-# include <pwd.h>
-#endif
-
 /*
  * Unix system-dependent file names
  */

test/unit/os/users.moon

@@ -14,6 +14,7 @@ typedef struct growarray {
 int mch_get_usernames(garray_T *usernames);
 int mch_get_user_name(char *s, size_t len);
 int mch_get_uname(int uid, char *s, size_t len);
+char *mch_get_user_directory(const char *name);
 int getuid(void);
 ]]
 
@@ -75,3 +76,15 @@ describe 'users function', ->
       eq FAIL, users.mch_get_uname(user_id, name_out, 100)
       eq '2342', ffi.string name_out
 
+  describe 'mch_get_user_directory', ->
+
+    it 'should return NULL if called with NULL', ->
+      eq NULL, users.mch_get_user_directory NULL
+
+    it 'should return $HOME for the current user', ->
+      home = os.getenv('HOME')
+      eq home, ffi.string (users.mch_get_user_directory current_username)
+
+    it 'should return NULL if the user is not found', ->
+      eq NULL, users.mch_get_user_directory 'neovim_user_not_found_test'
+