merge revision(s) 45287:45290: [Backport #9600]

	* process.c (obj2uid, obj2gid): now getpwnam_r() and getgrnam_r()
	  may need larger buffers than sysconf values, so retry with
	  expanding the buffer when ERANGE is returned.
	  [ruby-core:61325] [Bug #9600]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@46511 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 50 insertions, 4 deletions

diff --git a/process.c b/process.c
index d351a398d3..6c9cc7c153 100644
--- a/process.c
+++ b/process.c
@@ -147,6 +147,9 @@ static void check_gid_switch(void);
 #if defined(HAVE_PWD_H)
 # if defined(HAVE_GETPWNAM_R) && defined(_SC_GETPW_R_SIZE_MAX)
 #  define USE_GETPWNAM_R 1
+#  define GETPW_R_SIZE_INIT sysconf(_SC_GETPW_R_SIZE_MAX)
+#  define GETPW_R_SIZE_DEFAULT 0x1000
+#  define GETPW_R_SIZE_LIMIT  0x10000
 # endif
 # ifdef USE_GETPWNAM_R
 #   define PREPARE_GETPWNAM \
@@ -171,6 +174,9 @@ static rb_uid_t obj2uid(VALUE id);
 #if defined(HAVE_GRP_H)
 # if defined(HAVE_GETGRNAM_R) && defined(_SC_GETGR_R_SIZE_MAX)
 #  define USE_GETGRNAM_R
+#  define GETGR_R_SIZE_INIT sysconf(_SC_GETGR_R_SIZE_MAX)
+#  define GETGR_R_SIZE_DEFAULT 0x1000
+#  define GETGR_R_SIZE_LIMIT  0x10000
 # endif
 # ifdef USE_GETGRNAM_R
 #   define PREPARE_GETGRNAM \
@@ -4744,8 +4750,28 @@ obj2uid(VALUE id
 	struct passwd *pwptr;
 #ifdef USE_GETPWNAM_R
 	struct passwd pwbuf;
-	if (getpwnam_r(usrname, &pwbuf, getpw_buf, getpw_buf_len, &pwptr))
-	    rb_sys_fail("getpwnam_r");
+	char *getpw_buf;
+	long getpw_buf_len;
+	if (!*getpw_tmp) {
+	    getpw_buf_len = GETPW_R_SIZE_INIT;
+	    if (getpw_buf_len < 0) getpw_buf_len = GETPW_R_SIZE_DEFAULT;
+	    getpw_buf = rb_alloc_tmp_buffer(getpw_tmp, getpw_buf_len);
+	}
+	else {
+	    getpw_buf = RSTRING_PTR(*getpw_tmp);
+	    getpw_buf_len = rb_str_capacity(*getpw_tmp);
+	}
+	errno = ERANGE;
+	/* gepwnam_r() on MacOS X doesn't set errno if buffer size is insufficient */
+	while (getpwnam_r(usrname, &pwbuf, getpw_buf, getpw_buf_len, &pwptr)) {
+	    if (errno != ERANGE || getpw_buf_len >= GETPW_R_SIZE_LIMIT) {
+		rb_free_tmp_buffer(getpw_tmp);
+		rb_sys_fail("getpwnam_r");
+	    }
+	    rb_str_modify_expand(*getpw_tmp, getpw_buf_len);
+	    getpw_buf = RSTRING_PTR(*getpw_tmp);
+	    getpw_buf_len = rb_str_capacity(*getpw_tmp);
+	}
 #else
 	pwptr = getpwnam(usrname);
 #endif
@@ -4792,8 +4818,28 @@ obj2gid(VALUE id
 	struct group *grptr;
 #ifdef USE_GETGRNAM_R
 	struct group grbuf;
-	if (getgrnam_r(grpname, &grbuf, getgr_buf, getgr_buf_len, &grptr))
-	    rb_sys_fail("getgrnam_r");
+	char *getgr_buf;
+	long getgr_buf_len;
+	if (!*getgr_tmp) {
+	    getgr_buf_len = GETGR_R_SIZE_INIT;
+	    if (getgr_buf_len < 0) getgr_buf_len = GETGR_R_SIZE_DEFAULT;
+	    getgr_buf = rb_alloc_tmp_buffer(getgr_tmp, getgr_buf_len);
+	}
+	else {
+	    getgr_buf = RSTRING_PTR(*getgr_tmp);
+	    getgr_buf_len = rb_str_capacity(*getgr_tmp);
+	}
+	errno = ERANGE;
+	/* gegrnam_r() on MacOS X doesn't set errno if buffer size is insufficient */
+	while (getgrnam_r(grpname, &grbuf, getgr_buf, getgr_buf_len, &grptr)) {
+	    if (errno != ERANGE || getgr_buf_len >= GETGR_R_SIZE_LIMIT) {
+		rb_free_tmp_buffer(getgr_tmp);
+		rb_sys_fail("getgrnam_r");
+	    }
+	    rb_str_modify_expand(*getgr_tmp, getgr_buf_len);
+	    getgr_buf = RSTRING_PTR(*getgr_tmp);
+	    getgr_buf_len = rb_str_capacity(*getgr_tmp);
+	}
 #else
 	grptr = getgrnam(grpname);
 #endif