convert: use skip_iprefix() in validate_encoding()

Use skip_iprefix() to parse "UTF" case-insensitively instead of checking
with istarts_with(), building an upper-case version and then using
skip_prefix() on it.  This gets rid of duplicate code and of a small
allocation.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/convert.c b/convert.c
index 25ac525d5fa5ea5ac68f8a7a998fe2359b515530..99f684bf3e598cfa02cb21f347225916206ea00c 100644 (file)
--- a/convert.c
+++ b/convert.c
@@ -270,8 +270,12 @@ static int will_convert_lf_to_crlf(struct text_stat *stats,
 static int validate_encoding(const char *path, const char *enc,
                      const char *data, size_t len, int die_on_error)
 {
+       const char *stripped;
+
        /* We only check for UTF here as UTF?? can be an alias for UTF-?? */
-       if (istarts_with(enc, "UTF")) {
+       if (skip_iprefix(enc, "UTF", &stripped)) {
+               skip_prefix(stripped, "-", &stripped);
+
                /*
                 * Check for detectable errors in UTF encodings
                 */
@@ -285,15 +289,10 @@ static int validate_encoding(const char *path, const char *enc,
                         */
                        const char *advise_msg = _(
                                "The file '%s' contains a byte order "
-                               "mark (BOM). Please use UTF-%s as "
+                               "mark (BOM). Please use UTF-%.*s as "
                                "working-tree-encoding.");
-                       const char *stripped = NULL;
-                       char *upper = xstrdup_toupper(enc);
-                       upper[strlen(upper)-2] = '\0';
-                       if (skip_prefix(upper, "UTF", &stripped))
-                               skip_prefix(stripped, "-", &stripped);
-                       advise(advise_msg, path, stripped);
-                       free(upper);
+                       int stripped_len = strlen(stripped) - strlen("BE");
+                       advise(advise_msg, path, stripped_len, stripped);
                        if (die_on_error)
                                die(error_msg, path, enc);
                        else {
@@ -308,12 +307,7 @@ static int validate_encoding(const char *path, const char *enc,
                                "mark (BOM). Please use UTF-%sBE or UTF-%sLE "
                                "(depending on the byte order) as "
                                "working-tree-encoding.");
-                       const char *stripped = NULL;
-                       char *upper = xstrdup_toupper(enc);
-                       if (skip_prefix(upper, "UTF", &stripped))
-                               skip_prefix(stripped, "-", &stripped);
                        advise(advise_msg, path, stripped, stripped);
-                       free(upper);
                        if (die_on_error)
                                die(error_msg, path, enc);
                        else {