Reorganize `mrb_string_value_cstr` and related functions.

`mrb_string_value_cstr` and `mrb_string_value_len`: obsolete
`mrb_string_cstr`: new function to retrieve NULL terminated C string
`RSTRING_CSTR`: wrapper macro of `mrb_string_cstr`

8 files changed, 49 insertions, 41 deletions

diff --git a/include/mruby/string.h b/include/mruby/string.h
index d17ac1c1d..7266c9084 100644
--- a/include/mruby/string.h
+++ b/include/mruby/string.h
@@ -96,6 +96,7 @@ struct RString {
 #define RSTRING_CAPA(s)      RSTR_CAPA(RSTRING(s))
 #define RSTRING_END(s)       (RSTRING_PTR(s) + RSTRING_LEN(s))
 MRB_API mrb_int mrb_str_strlen(mrb_state*, struct RString*);
+#define RSTRING_CSTR(mrb,s)  mrb_string_cstr(mrb, s)
 
 #define MRB_STR_SHARED    1
 #define MRB_STR_FSHARED   2
@@ -337,16 +338,13 @@ MRB_API mrb_value mrb_string_type(mrb_state *mrb, mrb_value str);
 MRB_API mrb_value mrb_str_new_capa(mrb_state *mrb, size_t capa);
 MRB_API mrb_value mrb_str_buf_new(mrb_state *mrb, size_t capa);
 
-MRB_API const char *mrb_string_value_cstr(mrb_state *mrb, mrb_value *ptr);
+/* NULL terminated C string from mrb_value */
+MRB_API const char *mrb_string_cstr(mrb_state *mrb, mrb_value str);
+/* NULL terminated C string from mrb_value; `str` will be updated */
+MRB_API const char *mrb_string_value_cstr(mrb_state *mrb, mrb_value *str);
+/* obslete: use RSTRING_PTR() */
 MRB_API const char *mrb_string_value_ptr(mrb_state *mrb, mrb_value str);
-/*
- * Returns the length of the Ruby string.
- *
- *
- * @param [mrb_state] mrb The current mruby state.
- * @param [mrb_value] str Ruby string.
- * @return [mrb_int] The length of the passed in Ruby string.
- */
+/* obslete: use RSTRING_LEN() */
 MRB_API mrb_int mrb_string_value_len(mrb_state *mrb, mrb_value str);
 
 /*
diff --git a/mrbgems/mruby-io/src/file.c b/mrbgems/mruby-io/src/file.c
index 5e6c849f0..2fbda90af 100644
--- a/mrbgems/mruby-io/src/file.c
+++ b/mrbgems/mruby-io/src/file.c
@@ -116,7 +116,7 @@ mrb_file_s_unlink(mrb_state *mrb, mrb_value obj)
   for (i = 0; i < argc; i++) {
     const char *utf8_path;
     pathv = mrb_ensure_string_type(mrb, argv[i]);
-    utf8_path = mrb_string_value_cstr(mrb, &pathv);
+    utf8_path = RSTRING_CSTR(mrb, pathv);
     path = mrb_locale_from_utf8(utf8_path, -1);
     if (UNLINK(path) < 0) {
       mrb_locale_free(path);
@@ -134,8 +134,8 @@ mrb_file_s_rename(mrb_state *mrb, mrb_value obj)
   char *src, *dst;
 
   mrb_get_args(mrb, "SS", &from, &to);
-  src = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &from), -1);
-  dst = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &to), -1);
+  src = mrb_locale_from_utf8(RSTRING_CSTR(mrb, from), -1);
+  dst = mrb_locale_from_utf8(RSTRING_CSTR(mrb, to), -1);
   if (rename(src, dst) < 0) {
 #if defined(_WIN32) || defined(_WIN64)
     if (CHMOD(dst, 0666) == 0 && UNLINK(dst) == 0 && rename(src, dst) == 0) {
@@ -146,7 +146,7 @@ mrb_file_s_rename(mrb_state *mrb, mrb_value obj)
 #endif
     mrb_locale_free(src);
     mrb_locale_free(dst);
-    mrb_sys_fail(mrb, RSTRING_PTR(mrb_format(mrb, "(%v, %v)", from, to)));
+    mrb_sys_fail(mrb, RSTRING_CSTR(mrb, mrb_format(mrb, "(%v, %v)", from, to)));
   }
   mrb_locale_free(src);
   mrb_locale_free(dst);
@@ -248,7 +248,7 @@ mrb_file_realpath(mrb_state *mrb, mrb_value klass)
     s = mrb_str_append(mrb, s, pathname);
     pathname = s;
   }
-  cpath = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &pathname), -1);
+  cpath = mrb_locale_from_utf8(RSTRING_CSTR(mrb, pathname), -1);
   result = mrb_str_buf_new(mrb, PATH_MAX);
   if (realpath(cpath, RSTRING_PTR(result)) == NULL) {
     mrb_locale_free(cpath);
@@ -300,7 +300,7 @@ mrb_file__gethome(mrb_state *mrb, mrb_value klass)
       mrb_raise(mrb, E_ARGUMENT_ERROR, "non-absolute home");
     }
   } else {
-    const char *cuser = mrb_string_value_cstr(mrb, &username);
+    const char *cuser = RSTRING_CSTR(mrb, username);
     struct passwd *pwd = getpwnam(cuser);
     if (pwd == NULL) {
       return mrb_nil_value();
@@ -393,12 +393,12 @@ mrb_file_s_symlink(mrb_state *mrb, mrb_value klass)
   int ai = mrb_gc_arena_save(mrb);
 
   mrb_get_args(mrb, "SS", &from, &to);
-  src = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &from), -1);
-  dst = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &to), -1);
+  src = mrb_locale_from_utf8(RSTRING_CSTR(mrb, from), -1);
+  dst = mrb_locale_from_utf8(RSTRING_CSTR(mrb, to), -1);
   if (symlink(src, dst) == -1) {
     mrb_locale_free(src);
     mrb_locale_free(dst);
-    mrb_sys_fail(mrb, RSTRING_PTR(mrb_format(mrb, "(%v, %v)", from, to)));
+    mrb_sys_fail(mrb, RSTRING_CSTR(mrb, mrb_format(mrb, "(%v, %v)", from, to)));
   }
   mrb_locale_free(src);
   mrb_locale_free(dst);
@@ -416,7 +416,7 @@ mrb_file_s_chmod(mrb_state *mrb, mrb_value klass) {
 
   mrb_get_args(mrb, "i*", &mode, &filenames, &argc);
   for (i = 0; i < argc; i++) {
-    const char *utf8_path = mrb_string_value_cstr(mrb, &filenames[i]);
+    const char *utf8_path = RSTRING_CSTR(mrb, filenames[i]);
     char *path = mrb_locale_from_utf8(utf8_path, -1);
     if (CHMOD(path, mode) == -1) {
       mrb_locale_free(path);
diff --git a/mrbgems/mruby-io/src/file_test.c b/mrbgems/mruby-io/src/file_test.c
index 85a221ff9..445bafde9 100644
--- a/mrbgems/mruby-io/src/file_test.c
+++ b/mrbgems/mruby-io/src/file_test.c
@@ -54,7 +54,7 @@ mrb_stat0(mrb_state *mrb, mrb_value obj, struct stat *st, int do_lstat)
     return -1;
   }
   else {
-    char *path = mrb_locale_from_utf8(mrb_string_value_cstr(mrb, &obj), -1);
+    char *path = mrb_locale_from_utf8(RSTRING_CSTR(mrb, obj), -1);
     int ret;
     if (do_lstat) {
       ret = LSTAT(path, st);
diff --git a/mrbgems/mruby-io/src/io.c b/mrbgems/mruby-io/src/io.c
index a43ebcb91..eb9c4097b 100644
--- a/mrbgems/mruby-io/src/io.c
+++ b/mrbgems/mruby-io/src/io.c
@@ -332,8 +332,8 @@ mrb_io_s_popen(mrb_state *mrb, mrb_value klass)
   mrb_get_args(mrb, "S|SH", &cmd, &mode, &opt);
   io = mrb_obj_value(mrb_data_object_alloc(mrb, mrb_class_ptr(klass), NULL, &mrb_io_type));
 
-  pname = mrb_string_value_cstr(mrb, &cmd);
-  flags = mrb_io_modestr_to_flags(mrb, mrb_string_value_cstr(mrb, &mode));
+  pname = RSTRING_CSTR(mrb, cmd);
+  flags = mrb_io_modestr_to_flags(mrb, RSTRING_CSTR(mrb, mode));
 
   doexec = (strcmp("-", pname) != 0);
   opt_in = option_to_fd(mrb, opt, "in");
@@ -428,8 +428,8 @@ mrb_io_s_popen(mrb_state *mrb, mrb_value klass)
   mrb_get_args(mrb, "S|SH", &cmd, &mode, &opt);
   io = mrb_obj_value(mrb_data_object_alloc(mrb, mrb_class_ptr(klass), NULL, &mrb_io_type));
 
-  pname = mrb_string_value_cstr(mrb, &cmd);
-  flags = mrb_io_modestr_to_flags(mrb, mrb_string_value_cstr(mrb, &mode));
+  pname = RSTRING_CSTR(mrb, cmd);
+  flags = mrb_io_modestr_to_flags(mrb, RSTRING_CSTR(mrb, mode));
 
   doexec = (strcmp("-", pname) != 0);
   opt_in = option_to_fd(mrb, opt, "in");
@@ -626,7 +626,7 @@ mrb_io_initialize(mrb_state *mrb, mrb_value io)
     opt = mrb_hash_new(mrb);
   }
 
-  flags = mrb_io_modestr_to_flags(mrb, mrb_string_value_cstr(mrb, &mode));
+  flags = mrb_io_modestr_to_flags(mrb, RSTRING_CSTR(mrb, mode));
 
   mrb_iv_set(mrb, io, mrb_intern_cstr(mrb, "@buf"), mrb_str_new_cstr(mrb, ""));
 
@@ -780,7 +780,7 @@ reopen:
       }
     }
 
-    mrb_sys_fail(mrb, RSTRING_PTR(mrb_format(mrb, "open %s", pathname)));
+    mrb_sys_fail(mrb, RSTRING_CSTR(mrb, mrb_format(mrb, "open %s", pathname)));
   }
   mrb_locale_free(fname);
 
@@ -807,8 +807,8 @@ mrb_io_s_sysopen(mrb_state *mrb, mrb_value klass)
     perm = 0666;
   }
 
-  pat = mrb_string_value_cstr(mrb, &path);
-  flags = mrb_io_modestr_to_flags(mrb, mrb_string_value_cstr(mrb, &mode));
+  pat = RSTRING_CSTR(mrb, path);
+  flags = mrb_io_modestr_to_flags(mrb, RSTRING_CSTR(mrb, mode));
   modenum = mrb_io_flags_to_modenum(mrb, flags);
   fd = mrb_cloexec_open(mrb, pat, modenum, perm);
   return mrb_fixnum_value(fd);
diff --git a/mrbgems/mruby-socket/src/socket.c b/mrbgems/mruby-socket/src/socket.c
index eaca27779..53f761617 100644
--- a/mrbgems/mruby-socket/src/socket.c
+++ b/mrbgems/mruby-socket/src/socket.c
@@ -131,7 +131,7 @@ mrb_addrinfo_getaddrinfo(mrb_state *mrb, mrb_value klass)
   mrb_get_args(mrb, "oo|oooi", &nodename, &service, &family, &socktype, &protocol, &flags);
 
   if (mrb_string_p(nodename)) {
-    hostname = mrb_string_value_cstr(mrb, &nodename);
+    hostname = RSTRING_CSTR(mrb, nodename);
   } else if (mrb_nil_p(nodename)) {
     hostname = NULL;
   } else {
@@ -139,7 +139,7 @@ mrb_addrinfo_getaddrinfo(mrb_state *mrb, mrb_value klass)
   }
 
   if (mrb_string_p(service)) {
-    servname = mrb_string_value_cstr(mrb, &service);
+    servname = RSTRING_CSTR(mrb, service);
   } else if (mrb_fixnum_p(service)) {
     servname = RSTRING_PTR(mrb_fixnum_to_str(mrb, service, 10));
   } else if (mrb_nil_p(service)) {
diff --git a/mrbgems/mruby-test/vformat.c b/mrbgems/mruby-test/vformat.c
index 6e0c2887f..6984aaeb1 100644
--- a/mrbgems/mruby-test/vformat.c
+++ b/mrbgems/mruby-test/vformat.c
@@ -166,7 +166,7 @@ vf_s_format(mrb_state *mrb, mrb_value klass)
 {
   mrb_value fmt_str, args[2];
   mrb_int argc = mrb_get_args(mrb, "S|oo", &fmt_str, args, args+1);
-  const char *fmt = mrb_string_value_cstr(mrb, &fmt_str);
+  const char *fmt = RSTRING_CSTR(mrb, fmt_str);
 
   VF_FORMAT_INIT(klass);
 
diff --git a/src/class.c b/src/class.c
index ff55de0e6..5b190d28b 100644
--- a/src/class.c
+++ b/src/class.c
@@ -770,7 +770,7 @@ mrb_get_args(mrb_state *mrb, const char *format, ...)
         }
         if (i < argc) {
           ss = to_str(mrb, ARGV[arg_i++]);
-          *ps = mrb_string_value_cstr(mrb, &ss);
+          *ps = RSTRING_CSTR(mrb, ss);
           i++;
         }
       }
diff --git a/src/string.c b/src/string.c
index 71c6e126e..50c283593 100644
--- a/src/string.c
+++ b/src/string.c
@@ -1060,6 +1060,7 @@ mrb_str_to_str(mrb_state *mrb, mrb_value str)
   }
 }
 
+/* obslete: use RSTRING_PTR() */
 MRB_API const char*
 mrb_string_value_ptr(mrb_state *mrb, mrb_value str)
 {
@@ -1067,6 +1068,7 @@ mrb_string_value_ptr(mrb_state *mrb, mrb_value str)
   return RSTRING_PTR(str);
 }
 
+/* obslete: use RSTRING_LEN() */
 MRB_API mrb_int
 mrb_string_value_len(mrb_state *mrb, mrb_value ptr)
 {
@@ -2352,6 +2354,7 @@ mrb_cstr_to_inum(mrb_state *mrb, const char *str, mrb_int base, mrb_bool badchec
   return mrb_str_len_to_inum(mrb, str, strlen(str), base, badcheck);
 }
 
+/* obslete: use RSTRING_CSTR() or mrb_string_cstr() */
 MRB_API const char*
 mrb_string_value_cstr(mrb_state *mrb, mrb_value *ptr)
 {
@@ -2366,16 +2369,23 @@ mrb_string_value_cstr(mrb_state *mrb, mrb_value *ptr)
   if (p[len] == '\0') {
     return p;
   }
+  if (MRB_FROZEN_P(ps) || RSTR_CAPA(ps) == len) {
+    ps = str_new(mrb, NULL, len+1);
+    memcpy(RSTR_PTR(ps), p, len);
+    RSTR_SET_LEN(ps, len);
+    *ptr = mrb_obj_value(ps);
+  }
   else {
-    if (MRB_FROZEN_P(ps)) {
-      ps = str_new(mrb, p, len);
-      *ptr = mrb_obj_value(ps);
-    }
-    else {
-      mrb_str_modify(mrb, ps);
-    }
-    return RSTR_PTR(ps);
+    mrb_str_modify(mrb, ps);
   }
+  RSTR_PTR(ps)[len] = '\0';
+  return RSTR_PTR(ps);
+}
+
+MRB_API const char*
+mrb_string_cstr(mrb_state *mrb, mrb_value str)
+{
+  return mrb_string_value_cstr(mrb, &str);
 }
 
 MRB_API mrb_value
@@ -2489,7 +2499,7 @@ bad:
 MRB_API double
 mrb_str_to_dbl(mrb_state *mrb, mrb_value str, mrb_bool badcheck)
 {
-  return mrb_cstr_to_dbl(mrb, mrb_string_value_cstr(mrb, &str), badcheck);
+  return mrb_cstr_to_dbl(mrb, RSTRING_CSTR(mrb, str), badcheck);
 }
 
 /* 15.2.10.5.39 */